Bump version to 0.9.8

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

.gitignore

@@ -5,6 +5,7 @@
 *~$
 cscope.*
 compile_commands.json
+/.cache
 /.clangd
 tags
 /build

.gitlab-ci.yml

@@ -2,6 +2,8 @@ variables:
   BUILD_IMAGES_PROJECT: libssh/build-images
   FEDORA_BUILD: buildenv-fedora
   CENTOS7_BUILD: buildenv-centos7
+  CENTOS8_BUILD: buildenv-c8s
+  CENTOS9_BUILD: buildenv-c9s
   TUMBLEWEED_BUILD: buildenv-tumbleweed
   MINGW_BUILD: buildenv-mingw
 
@@ -25,6 +27,47 @@ centos7/openssl_1.0.x/x86_64:
     paths:
       - obj/
 
+centos8/openssl_1.1.1/x86_64:
+  image: $CI_REGISTRY/$BUILD_IMAGES_PROJECT:$CENTOS8_BUILD
+  script:
+    - mkdir -p obj && cd obj && cmake
+      -DCMAKE_BUILD_TYPE=RelWithDebInfo
+      -DPICKY_DEVELOPER=ON
+      -DWITH_BLOWFISH_CIPHER=ON
+      -DWITH_SFTP=ON -DWITH_SERVER=ON -DWITH_ZLIB=ON -DWITH_PCAP=ON
+      -DUNIT_TESTING=ON -DCLIENT_TESTING=ON -DSERVER_TESTING=ON .. &&
+      make -j$(nproc) && ctest --output-on-failure
+  tags:
+    - shared
+  except:
+    - tags
+  artifacts:
+    expire_in: 1 week
+    when: on_failure
+    paths:
+      - obj/
+
+centos9/openssl_3.0.x/x86_64:
+  image: $CI_REGISTRY/$BUILD_IMAGES_PROJECT:$CENTOS9_BUILD
+  script:
+    - export OPENSSL_ENABLE_SHA1_SIGNATURES=1
+    - mkdir -p obj && cd obj && cmake
+      -DCMAKE_BUILD_TYPE=RelWithDebInfo
+      -DPICKY_DEVELOPER=ON
+      -DWITH_BLOWFISH_CIPHER=ON
+      -DWITH_SFTP=ON -DWITH_SERVER=ON -DWITH_ZLIB=ON -DWITH_PCAP=ON
+      -DUNIT_TESTING=ON -DCLIENT_TESTING=ON -DSERVER_TESTING=ON .. &&
+      make -j$(nproc) && ctest --output-on-failure
+  tags:
+    - shared
+  except:
+    - tags
+  artifacts:
+    expire_in: 1 week
+    when: on_failure
+    paths:
+      - obj/
+
 fedora/openssl_1.1.x/x86_64:
   image: $CI_REGISTRY/$BUILD_IMAGES_PROJECT:$FEDORA_BUILD
   script:
@@ -47,8 +90,8 @@ fedora/openssl_1.1.x/x86_64:
     paths:
       - obj/
 
-fedora/openssl_1.1.x/x86_64/fips:
-  image: $CI_REGISTRY/$BUILD_IMAGES_PROJECT:$FEDORA_BUILD
+centos8/openssl_1.1.1/x86_64/fips:
+  image: $CI_REGISTRY/$BUILD_IMAGES_PROJECT:$CENTOS8_BUILD
   script:
   - echo 1 > /etc/system-fips
   - update-crypto-policies --set FIPS
@@ -469,47 +512,34 @@ tumbleweed/static-analysis:
   variables:
     ErrorActionPreference: STOP
   script:
-  - $env:VCPKG_DEFAULT_TRIPLET="x64-windows"
-  - mkdir -p obj; if ($?) {cd obj}; if (! $?) {exit 1}
-  - cmake
-      -A x64
-      -DCMAKE_TOOLCHAIN_FILE="$env:VCPKG_TOOLCHAIN_FILE"
-      -DPICKY_DEVELOPER=ON
-      -DWITH_SFTP=ON -DWITH_SERVER=ON -DWITH_ZLIB=ON -DWITH_PCAP=ON
-      -DUNIT_TESTING=ON ..
-  - cmake --build .
-  - ctest --output-on-failure
+    - cmake --build .
+    - ctest --output-on-failure
   tags:
-  - windows
-  - shared-windows
+    - windows
+    - shared-windows
   except:
-  - tags
+    - tags
   artifacts:
     expire_in: 1 week
     when: on_failure
     paths:
       - obj/
   before_script:
-  - choco install --no-progress -y cmake
-  - $env:Path += ';C:\Program Files\CMake\bin'
-  - If (!(test-path .vcpkg\archives)) { mkdir -p .vcpkg\archives }
-  - $env:VCPKG_DEFAULT_BINARY_CACHE="$PWD\.vcpkg\archives"
-  - echo $env:VCPKG_DEFAULT_BINARY_CACHE
-  - $env:VCPKG_DEFAULT_TRIPLET="$TRIPLET-windows"
-  - vcpkg install cmocka
-  - vcpkg install openssl
-  - vcpkg install zlib
-  - vcpkg integrate install
-  - mkdir -p obj; if ($?) {cd obj}; if (! $?) {exit 1}
-  - cmake
-      -A $PLATFORM
-      -DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake
-      -DPICKY_DEVELOPER=ON
-      -DWITH_SFTP=ON -DWITH_SERVER=ON -DWITH_ZLIB=ON -DWITH_PCAP=ON
-      -DUNIT_TESTING=ON ..
-  # The Windows runners are broken for last month
-  # https://gitlab.com/gitlab-org/ci-cd/shared-runners/images/gcp/windows-containers/-/issues/40
-  allow_failure: true
+    - If (!(test-path .vcpkg\archives)) { mkdir -p .vcpkg\archives }
+    - $env:VCPKG_DEFAULT_BINARY_CACHE="$PWD\.vcpkg\archives"
+    - echo $env:VCPKG_DEFAULT_BINARY_CACHE
+    - $env:VCPKG_DEFAULT_TRIPLET="$TRIPLET-windows"
+    - vcpkg install cmocka
+    - vcpkg install openssl
+    - vcpkg install zlib
+    - vcpkg integrate install
+    - mkdir -p obj; if ($?) {cd obj}; if (! $?) {exit 1}
+    - cmake
+        -A $PLATFORM
+        -DCMAKE_TOOLCHAIN_FILE=C:/vcpkg/scripts/buildsystems/vcpkg.cmake
+        -DPICKY_DEVELOPER=ON
+        -DWITH_SFTP=ON -DWITH_SERVER=ON -DWITH_ZLIB=ON -DWITH_PCAP=ON
+        -DUNIT_TESTING=ON ..
 
 visualstudio/x86_64:
   extends: .vs

CMakeLists.txt

@@ -10,7 +10,7 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules")
 include(DefineCMakeDefaults)
 include(DefineCompilerFlags)
 
-project(libssh VERSION 0.9.6 LANGUAGES C)
+project(libssh VERSION 0.9.8 LANGUAGES C)
 
 # global needed variable
 set(APPLICATION_NAME ${PROJECT_NAME})
@@ -22,7 +22,7 @@ set(APPLICATION_NAME ${PROJECT_NAME})
 #     Increment AGE. Set REVISION to 0
 #   If the source code was changed, but there were no interface changes:
 #     Increment REVISION.
-set(LIBRARY_VERSION "4.8.7")
+set(LIBRARY_VERSION "4.8.9")
 set(LIBRARY_SOVERSION "4")
 
 # where to look first for cmake modules, before ${CMAKE_ROOT}/Modules/ is checked

CPackConfig.cmake

@@ -10,7 +10,7 @@ set(CPACK_PACKAGE_VERSION ${PROJECT_VERSION})
 
 # SOURCE GENERATOR
 set(CPACK_SOURCE_GENERATOR "TXZ")
-set(CPACK_SOURCE_IGNORE_FILES "~$;[.]swp$;/[.]git/;/[.]clangd/;.gitignore;/build*;/obj*;tags;cscope.*;compile_commands.json;.*\.patch")
+set(CPACK_SOURCE_IGNORE_FILES "~$;[.]swp$;/[.]git;/[.]clangd/;/[.]cache/;.gitignore;/build*;/obj*;tags;cscope.*;compile_commands.json;.*\.patch")
 set(CPACK_SOURCE_PACKAGE_FILE_NAME "${CPACK_PACKAGE_NAME}-${CPACK_PACKAGE_VERSION}")
 
 ### NSIS INSTALLER

ChangeLog

@@ -1,5 +1,17 @@
 ChangeLog
 ==========
+version 0.9.8 (released 2023-12-18)
+ * Fix CVE-2023-6004: Command injection using proxycommand
+ * Fix CVE-2023-48795: Potential downgrade attack using strict kex
+ * Fix CVE-2023-6918: Missing checks for return values of MD functions
+ * Allow @ in usernames when parsing from URI composes
+
+version 0.9.7 (released 2023-05-04)
+  * Fix CVE-2023-1667: a NULL dereference during rekeying with algorithm guessing
+  * Fix CVE-2023-2283: a possible authorization bypass in
+    pki_verify_data_signature under low-memory conditions.
+  * Fix several memory leaks in GSSAPI handling code
+  * Build and test related backports
 
 version 0.9.6 (released 2021-08-26)
   * CVE-2021-3634: Fix possible heap-buffer overflow when rekeying with

examples/sshnetcat.c

@@ -233,9 +233,10 @@ void set_pcap(ssh_session session){
 }
 
 void cleanup_pcap(void);
-void cleanup_pcap(){
+void cleanup_pcap(void)
+{
 	ssh_pcap_file_free(pcap);
-	pcap=NULL;
+	pcap = NULL;
 }
 #endif
 

include/libssh/curve25519.h

@@ -48,6 +48,7 @@ typedef unsigned char ssh_curve25519_privkey[CURVE25519_PRIVKEY_SIZE];
 
 
 int ssh_client_curve25519_init(ssh_session session);
+void ssh_client_curve25519_remove_callbacks(ssh_session session);
 
 #ifdef WITH_SERVER
 void ssh_server_curve25519_init(ssh_session session);

include/libssh/dh-gex.h

@@ -24,6 +24,7 @@
 #define SRC_DH_GEX_H_
 
 int ssh_client_dhgex_init(ssh_session session);
+void ssh_client_dhgex_remove_callbacks(ssh_session session);
 
 #ifdef WITH_SERVER
 void ssh_server_dhgex_init(ssh_session session);

include/libssh/dh.h

@@ -63,8 +63,10 @@ int ssh_dh_get_current_server_publickey_blob(ssh_session session,
 ssh_key ssh_dh_get_next_server_publickey(ssh_session session);
 int ssh_dh_get_next_server_publickey_blob(ssh_session session,
                                           ssh_string *pubkey_blob);
+int dh_handshake(ssh_session session);
 
 int ssh_client_dh_init(ssh_session session);
+void ssh_client_dh_remove_callbacks(ssh_session session);
 #ifdef WITH_SERVER
 void ssh_server_dh_init(ssh_session session);
 #endif /* WITH_SERVER */

include/libssh/ecdh.h

@@ -45,6 +45,7 @@
 extern struct ssh_packet_callbacks_struct ssh_ecdh_client_callbacks;
 /* Backend-specific functions.  */
 int ssh_client_ecdh_init(ssh_session session);
+void ssh_client_ecdh_remove_callbacks(ssh_session session);
 int ecdh_build_k(ssh_session session);
 
 #ifdef WITH_SERVER

include/libssh/kex.h

@@ -33,9 +33,10 @@ struct ssh_kex_struct {
 
 SSH_PACKET_CALLBACK(ssh_packet_kexinit);
 
-int ssh_send_kex(ssh_session session, int server_kex);
+int ssh_send_kex(ssh_session session);
 void ssh_list_kex(struct ssh_kex_struct *kex);
 int ssh_set_client_kex(ssh_session session);
+int ssh_kex_append_extensions(ssh_session session, struct ssh_kex_struct *pkex);
 int ssh_kex_select_methods(ssh_session session);
 int ssh_verify_existing_algo(enum ssh_kex_types_e algo, const char *name);
 char *ssh_keep_known_algos(enum ssh_kex_types_e algo, const char *list);

include/libssh/libcrypto.h

@@ -39,11 +39,6 @@ typedef EVP_MD_CTX* SHA384CTX;
 typedef EVP_MD_CTX* SHA512CTX;
 typedef EVP_MD_CTX* MD5CTX;
 typedef HMAC_CTX* HMACCTX;
-#ifdef HAVE_ECC
-typedef EVP_MD_CTX *EVPCTX;
-#else
-typedef void *EVPCTX;
-#endif
 
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH
 #define SHA256_DIGEST_LEN SHA256_DIGEST_LENGTH

include/libssh/libgcrypt.h

@@ -32,7 +32,6 @@ typedef gcry_md_hd_t SHA384CTX;
 typedef gcry_md_hd_t SHA512CTX;
 typedef gcry_md_hd_t MD5CTX;
 typedef gcry_md_hd_t HMACCTX;
-typedef gcry_md_hd_t EVPCTX;
 #define SHA_DIGEST_LENGTH 20
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH
 #define MD5_DIGEST_LEN 16

include/libssh/libmbedcrypto.h

@@ -41,7 +41,6 @@ typedef mbedtls_md_context_t *SHA384CTX;
 typedef mbedtls_md_context_t *SHA512CTX;
 typedef mbedtls_md_context_t *MD5CTX;
 typedef mbedtls_md_context_t *HMACCTX;
-typedef mbedtls_md_context_t *EVPCTX;
 
 #define SHA_DIGEST_LENGTH 20
 #define SHA_DIGEST_LEN SHA_DIGEST_LENGTH

include/libssh/misc.h

@@ -97,4 +97,6 @@ int ssh_mkdirs(const char *pathname, mode_t mode);
 int ssh_quote_file_name(const char *file_name, char *buf, size_t buf_len);
 int ssh_newline_vis(const char *string, char *buf, size_t buf_len);
 
+int ssh_check_hostname_syntax(const char *hostname);
+
 #endif /* MISC_H_ */

include/libssh/packet.h

@@ -63,6 +63,7 @@ SSH_PACKET_CALLBACK(ssh_packet_ext_info);
 SSH_PACKET_CALLBACK(ssh_packet_kexdh_init);
 #endif
 
+int ssh_packet_send_newkeys(ssh_session session);
 int ssh_packet_send_unimplemented(ssh_session session, uint32_t seqnum);
 int ssh_packet_parse_type(ssh_session session);
 //int packet_flush(ssh_session session, int enforce_blocking);

include/libssh/session.h

@@ -75,6 +75,17 @@ enum ssh_pending_call_e {
 /* Client successfully authenticated */
 #define SSH_SESSION_FLAG_AUTHENTICATED 2
 
+/* The KEXINIT message can be sent first by either of the parties so this flag
+ * indicates that the message was already sent to make sure it is sent and avoid
+ * sending it twice during key exchange to simplify the state machine. */
+#define SSH_SESSION_FLAG_KEXINIT_SENT 4
+
+/* The current SSH2 session implements the "strict KEX" feature and should behave
+ * differently on SSH2_MSG_NEWKEYS. */
+#define SSH_SESSION_FLAG_KEX_STRICT 0x0010
+/* Unexpected packets have been sent while the session was still unencrypted */
+#define SSH_SESSION_FLAG_KEX_TAINTED 0x0020
+
 /* codes to use with ssh_handle_packets*() */
 /* Infinite timeout */
 #define SSH_TIMEOUT_INFINITE -1
@@ -131,10 +142,8 @@ struct ssh_session_struct {
     /* Extensions negotiated using RFC 8308 */
     uint32_t extensions;
 
-    ssh_string banner; /* that's the issue banner from
-                       the server */
-    char *discon_msg; /* disconnect message from
-                         the remote host */
+    ssh_string banner; /* that's the issue banner from the server */
+    char *discon_msg; /* disconnect message from the remote host */
     ssh_buffer in_buffer;
     PACKET in_packet;
     ssh_buffer out_buffer;
@@ -158,25 +167,33 @@ struct ssh_session_struct {
         uint32_t current_method;
     } auth;
 
+    /* Sending this flag before key exchange to save one round trip during the
+     * key exchange. This might make sense on high-latency connections.
+     * So far internal only for testing. Usable only on the client side --
+     * there is no key exchange method that would start with server message */
+    bool send_first_kex_follows;
     /*
      * RFC 4253, 7.1: if the first_kex_packet_follows flag was set in
      * the received SSH_MSG_KEXINIT, but the guess was wrong, this
      * field will be set such that the following guessed packet will
-     * be ignored.  Once that packet has been received and ignored,
-     * this field is cleared.
+     * be ignored on the receiving side.  Once that packet has been received and
+     * ignored, this field is cleared.
+     * On the sending side, this is set after we got peer KEXINIT message and we
+     * need to resend the initial message of the negotiated KEX algorithm.
      */
-    int first_kex_follows_guess_wrong;
+    bool first_kex_follows_guess_wrong;
 
     ssh_buffer in_hashbuf;
     ssh_buffer out_hashbuf;
     struct ssh_crypto_struct *current_crypto;
-    struct ssh_crypto_struct *next_crypto;  /* next_crypto is going to be used after a SSH2_MSG_NEWKEYS */
+    /* next_crypto is going to be used after a SSH2_MSG_NEWKEYS */
+    struct ssh_crypto_struct *next_crypto;
 
     struct ssh_list *channels; /* linked list of channels */
     int maxchannel;
     ssh_agent agent; /* ssh agent */
 
-/* keyb interactive data */
+    /* keyboard interactive data */
     struct ssh_kbdint_struct *kbdint;
     struct ssh_gssapi_struct *gssapi;
 
@@ -193,7 +210,8 @@ struct ssh_session_struct {
 
     /* auths accepted by server */
     struct ssh_list *ssh_message_list; /* list of delayed SSH messages */
-    int (*ssh_message_callback)( struct ssh_session_struct *session, ssh_message msg, void *userdata);
+    int (*ssh_message_callback)(struct ssh_session_struct *session,
+                                ssh_message msg, void *userdata);
     void *ssh_message_callback_data;
     ssh_server_callbacks server_callbacks;
     void (*ssh_connection_callback)( struct ssh_session_struct *session);
@@ -219,7 +237,7 @@ struct ssh_session_struct {
         char *custombanner;
         unsigned long timeout; /* seconds */
         unsigned long timeout_usec;
-        unsigned int port;
+        uint16_t port;
         socket_t fd;
         int StrictHostKeyChecking;
         char compressionlevel;

include/libssh/wrapper.h

@@ -67,37 +67,38 @@ struct ssh_crypto_struct;
 
 typedef struct ssh_mac_ctx_struct *ssh_mac_ctx;
 MD5CTX md5_init(void);
-void md5_update(MD5CTX c, const void *data, unsigned long len);
-void md5_final(unsigned char *md,MD5CTX c);
+void md5_ctx_free(MD5CTX);
+int md5_update(MD5CTX c, const void *data, unsigned long len);
+int md5_final(unsigned char *md,MD5CTX c);
 
 SHACTX sha1_init(void);
-void sha1_update(SHACTX c, const void *data, unsigned long len);
-void sha1_final(unsigned char *md,SHACTX c);
-void sha1(const unsigned char *digest,int len,unsigned char *hash);
+void sha1_ctx_free(SHACTX);
+int sha1_update(SHACTX c, const void *data, unsigned long len);
+int sha1_final(unsigned char *md,SHACTX c);
+int sha1(const unsigned char *digest,int len,unsigned char *hash);
 
 SHA256CTX sha256_init(void);
-void sha256_update(SHA256CTX c, const void *data, unsigned long len);
-void sha256_final(unsigned char *md,SHA256CTX c);
-void sha256(const unsigned char *digest, int len, unsigned char *hash);
+void sha256_ctx_free(SHA256CTX);
+int sha256_update(SHA256CTX c, const void *data, unsigned long len);
+int sha256_final(unsigned char *md,SHA256CTX c);
+int sha256(const unsigned char *digest, int len, unsigned char *hash);
 
 SHA384CTX sha384_init(void);
-void sha384_update(SHA384CTX c, const void *data, unsigned long len);
-void sha384_final(unsigned char *md,SHA384CTX c);
-void sha384(const unsigned char *digest, int len, unsigned char *hash);
+void sha384_ctx_free(SHA384CTX);
+int sha384_update(SHA384CTX c, const void *data, unsigned long len);
+int sha384_final(unsigned char *md,SHA384CTX c);
+int sha384(const unsigned char *digest, int len, unsigned char *hash);
 
 SHA512CTX sha512_init(void);
-void sha512_update(SHA512CTX c, const void *data, unsigned long len);
-void sha512_final(unsigned char *md,SHA512CTX c);
-void sha512(const unsigned char *digest, int len, unsigned char *hash);
-
-void evp(int nid, unsigned char *digest, int len, unsigned char *hash, unsigned int *hlen);
-EVPCTX evp_init(int nid);
-void evp_update(EVPCTX ctx, const void *data, unsigned long len);
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen);
+void sha512_ctx_free(SHA512CTX);
+int sha512_update(SHA512CTX c, const void *data, unsigned long len);
+int sha512_final(unsigned char *md,SHA512CTX c);
+int sha512(const unsigned char *digest, int len, unsigned char *hash);
 
 HMACCTX hmac_init(const void *key,int len, enum ssh_hmac_e type);
 void hmac_update(HMACCTX c, const void *data, unsigned long len);
 void hmac_final(HMACCTX ctx,unsigned char *hashmacbuf,unsigned int *len);
+
 size_t hmac_digest_len(enum ssh_hmac_e type);
 
 int ssh_kdf(struct ssh_crypto_struct *crypto,

src/ABI/current

@@ -1 +1 @@
-4.8.7
+4.8.9

src/ABI/libssh-4.8.8.symbols

@@ -0,0 +1,421 @@
+_ssh_log
+buffer_free
+buffer_get
+buffer_get_len
+buffer_new
+channel_accept_x11
+channel_change_pty_size
+channel_close
+channel_forward_accept
+channel_forward_cancel
+channel_forward_listen
+channel_free
+channel_get_exit_status
+channel_get_session
+channel_is_closed
+channel_is_eof
+channel_is_open
+channel_new
+channel_open_forward
+channel_open_session
+channel_poll
+channel_read
+channel_read_buffer
+channel_read_nonblocking
+channel_request_env
+channel_request_exec
+channel_request_pty
+channel_request_pty_size
+channel_request_send_signal
+channel_request_sftp
+channel_request_shell
+channel_request_subsystem
+channel_request_x11
+channel_select
+channel_send_eof
+channel_set_blocking
+channel_write
+channel_write_stderr
+privatekey_free
+privatekey_from_file
+publickey_free
+publickey_from_file
+publickey_from_privatekey
+publickey_to_string
+sftp_async_read
+sftp_async_read_begin
+sftp_attributes_free
+sftp_canonicalize_path
+sftp_chmod
+sftp_chown
+sftp_client_message_free
+sftp_client_message_get_data
+sftp_client_message_get_filename
+sftp_client_message_get_flags
+sftp_client_message_get_submessage
+sftp_client_message_get_type
+sftp_client_message_set_filename
+sftp_close
+sftp_closedir
+sftp_dir_eof
+sftp_extension_supported
+sftp_extensions_get_count
+sftp_extensions_get_data
+sftp_extensions_get_name
+sftp_file_set_blocking
+sftp_file_set_nonblocking
+sftp_free
+sftp_fstat
+sftp_fstatvfs
+sftp_fsync
+sftp_get_client_message
+sftp_get_error
+sftp_handle
+sftp_handle_alloc
+sftp_handle_remove
+sftp_init
+sftp_lstat
+sftp_mkdir
+sftp_new
+sftp_new_channel
+sftp_open
+sftp_opendir
+sftp_read
+sftp_readdir
+sftp_readlink
+sftp_rename
+sftp_reply_attr
+sftp_reply_data
+sftp_reply_handle
+sftp_reply_name
+sftp_reply_names
+sftp_reply_names_add
+sftp_reply_status
+sftp_rewind
+sftp_rmdir
+sftp_seek
+sftp_seek64
+sftp_send_client_message
+sftp_server_free
+sftp_server_init
+sftp_server_new
+sftp_server_version
+sftp_setstat
+sftp_stat
+sftp_statvfs
+sftp_statvfs_free
+sftp_symlink
+sftp_tell
+sftp_tell64
+sftp_unlink
+sftp_utimes
+sftp_write
+ssh_accept
+ssh_add_channel_callbacks
+ssh_auth_list
+ssh_basename
+ssh_bind_accept
+ssh_bind_accept_fd
+ssh_bind_fd_toaccept
+ssh_bind_free
+ssh_bind_get_fd
+ssh_bind_listen
+ssh_bind_new
+ssh_bind_options_parse_config
+ssh_bind_options_set
+ssh_bind_set_blocking
+ssh_bind_set_callbacks
+ssh_bind_set_fd
+ssh_blocking_flush
+ssh_buffer_add_data
+ssh_buffer_free
+ssh_buffer_get
+ssh_buffer_get_data
+ssh_buffer_get_len
+ssh_buffer_new
+ssh_buffer_reinit
+ssh_channel_accept_forward
+ssh_channel_accept_x11
+ssh_channel_cancel_forward
+ssh_channel_change_pty_size
+ssh_channel_close
+ssh_channel_free
+ssh_channel_get_exit_status
+ssh_channel_get_session
+ssh_channel_is_closed
+ssh_channel_is_eof
+ssh_channel_is_open
+ssh_channel_listen_forward
+ssh_channel_new
+ssh_channel_open_auth_agent
+ssh_channel_open_forward
+ssh_channel_open_forward_unix
+ssh_channel_open_reverse_forward
+ssh_channel_open_session
+ssh_channel_open_x11
+ssh_channel_poll
+ssh_channel_poll_timeout
+ssh_channel_read
+ssh_channel_read_nonblocking
+ssh_channel_read_timeout
+ssh_channel_request_auth_agent
+ssh_channel_request_env
+ssh_channel_request_exec
+ssh_channel_request_pty
+ssh_channel_request_pty_size
+ssh_channel_request_send_break
+ssh_channel_request_send_exit_signal
+ssh_channel_request_send_exit_status
+ssh_channel_request_send_signal
+ssh_channel_request_sftp
+ssh_channel_request_shell
+ssh_channel_request_subsystem
+ssh_channel_request_x11
+ssh_channel_select
+ssh_channel_send_eof
+ssh_channel_set_blocking
+ssh_channel_set_counter
+ssh_channel_window_size
+ssh_channel_write
+ssh_channel_write_stderr
+ssh_clean_pubkey_hash
+ssh_connect
+ssh_connector_free
+ssh_connector_new
+ssh_connector_set_in_channel
+ssh_connector_set_in_fd
+ssh_connector_set_out_channel
+ssh_connector_set_out_fd
+ssh_copyright
+ssh_dirname
+ssh_disconnect
+ssh_dump_knownhost
+ssh_event_add_connector
+ssh_event_add_fd
+ssh_event_add_session
+ssh_event_dopoll
+ssh_event_free
+ssh_event_new
+ssh_event_remove_connector
+ssh_event_remove_fd
+ssh_event_remove_session
+ssh_execute_message_callbacks
+ssh_finalize
+ssh_forward_accept
+ssh_forward_cancel
+ssh_forward_listen
+ssh_free
+ssh_get_cipher_in
+ssh_get_cipher_out
+ssh_get_clientbanner
+ssh_get_disconnect_message
+ssh_get_error
+ssh_get_error_code
+ssh_get_fd
+ssh_get_fingerprint_hash
+ssh_get_hexa
+ssh_get_hmac_in
+ssh_get_hmac_out
+ssh_get_issue_banner
+ssh_get_kex_algo
+ssh_get_log_callback
+ssh_get_log_level
+ssh_get_log_userdata
+ssh_get_openssh_version
+ssh_get_poll_flags
+ssh_get_pubkey
+ssh_get_pubkey_hash
+ssh_get_publickey
+ssh_get_publickey_hash
+ssh_get_random
+ssh_get_server_publickey
+ssh_get_serverbanner
+ssh_get_status
+ssh_get_version
+ssh_getpass
+ssh_gssapi_get_creds
+ssh_gssapi_set_creds
+ssh_handle_key_exchange
+ssh_init
+ssh_is_blocking
+ssh_is_connected
+ssh_is_server_known
+ssh_key_cmp
+ssh_key_free
+ssh_key_is_private
+ssh_key_is_public
+ssh_key_new
+ssh_key_type
+ssh_key_type_from_name
+ssh_key_type_to_char
+ssh_known_hosts_parse_line
+ssh_knownhosts_entry_free
+ssh_log
+ssh_message_auth_interactive_request
+ssh_message_auth_kbdint_is_response
+ssh_message_auth_password
+ssh_message_auth_pubkey
+ssh_message_auth_publickey
+ssh_message_auth_publickey_state
+ssh_message_auth_reply_pk_ok
+ssh_message_auth_reply_pk_ok_simple
+ssh_message_auth_reply_success
+ssh_message_auth_set_methods
+ssh_message_auth_user
+ssh_message_channel_request_channel
+ssh_message_channel_request_command
+ssh_message_channel_request_env_name
+ssh_message_channel_request_env_value
+ssh_message_channel_request_open_destination
+ssh_message_channel_request_open_destination_port
+ssh_message_channel_request_open_originator
+ssh_message_channel_request_open_originator_port
+ssh_message_channel_request_open_reply_accept
+ssh_message_channel_request_open_reply_accept_channel
+ssh_message_channel_request_pty_height
+ssh_message_channel_request_pty_pxheight
+ssh_message_channel_request_pty_pxwidth
+ssh_message_channel_request_pty_term
+ssh_message_channel_request_pty_width
+ssh_message_channel_request_reply_success
+ssh_message_channel_request_subsystem
+ssh_message_channel_request_x11_auth_cookie
+ssh_message_channel_request_x11_auth_protocol
+ssh_message_channel_request_x11_screen_number
+ssh_message_channel_request_x11_single_connection
+ssh_message_free
+ssh_message_get
+ssh_message_global_request_address
+ssh_message_global_request_port
+ssh_message_global_request_reply_success
+ssh_message_reply_default
+ssh_message_retrieve
+ssh_message_service_reply_success
+ssh_message_service_service
+ssh_message_subtype
+ssh_message_type
+ssh_mkdir
+ssh_new
+ssh_options_copy
+ssh_options_get
+ssh_options_get_port
+ssh_options_getopt
+ssh_options_parse_config
+ssh_options_set
+ssh_pcap_file_close
+ssh_pcap_file_free
+ssh_pcap_file_new
+ssh_pcap_file_open
+ssh_pki_copy_cert_to_privkey
+ssh_pki_export_privkey_base64
+ssh_pki_export_privkey_file
+ssh_pki_export_privkey_to_pubkey
+ssh_pki_export_pubkey_base64
+ssh_pki_export_pubkey_file
+ssh_pki_generate
+ssh_pki_import_cert_base64
+ssh_pki_import_cert_file
+ssh_pki_import_privkey_base64
+ssh_pki_import_privkey_file
+ssh_pki_import_pubkey_base64
+ssh_pki_import_pubkey_file
+ssh_pki_key_ecdsa_name
+ssh_print_hash
+ssh_print_hexa
+ssh_privatekey_type
+ssh_publickey_to_file
+ssh_remove_channel_callbacks
+ssh_scp_accept_request
+ssh_scp_close
+ssh_scp_deny_request
+ssh_scp_free
+ssh_scp_init
+ssh_scp_leave_directory
+ssh_scp_new
+ssh_scp_pull_request
+ssh_scp_push_directory
+ssh_scp_push_file
+ssh_scp_push_file64
+ssh_scp_read
+ssh_scp_request_get_filename
+ssh_scp_request_get_permissions
+ssh_scp_request_get_size
+ssh_scp_request_get_size64
+ssh_scp_request_get_warning
+ssh_scp_write
+ssh_select
+ssh_send_debug
+ssh_send_ignore
+ssh_send_keepalive
+ssh_server_init_kex
+ssh_service_request
+ssh_session_export_known_hosts_entry
+ssh_session_get_known_hosts_entry
+ssh_session_has_known_hosts_entry
+ssh_session_is_known_server
+ssh_session_update_known_hosts
+ssh_set_agent_channel
+ssh_set_agent_socket
+ssh_set_auth_methods
+ssh_set_blocking
+ssh_set_callbacks
+ssh_set_channel_callbacks
+ssh_set_counters
+ssh_set_fd_except
+ssh_set_fd_toread
+ssh_set_fd_towrite
+ssh_set_log_callback
+ssh_set_log_level
+ssh_set_log_userdata
+ssh_set_message_callback
+ssh_set_pcap_file
+ssh_set_server_callbacks
+ssh_silent_disconnect
+ssh_string_burn
+ssh_string_copy
+ssh_string_data
+ssh_string_fill
+ssh_string_free
+ssh_string_free_char
+ssh_string_from_char
+ssh_string_get_char
+ssh_string_len
+ssh_string_new
+ssh_string_to_char
+ssh_threads_get_default
+ssh_threads_get_noop
+ssh_threads_get_pthread
+ssh_threads_set_callbacks
+ssh_try_publickey_from_file
+ssh_userauth_agent
+ssh_userauth_agent_pubkey
+ssh_userauth_autopubkey
+ssh_userauth_gssapi
+ssh_userauth_kbdint
+ssh_userauth_kbdint_getanswer
+ssh_userauth_kbdint_getinstruction
+ssh_userauth_kbdint_getname
+ssh_userauth_kbdint_getnanswers
+ssh_userauth_kbdint_getnprompts
+ssh_userauth_kbdint_getprompt
+ssh_userauth_kbdint_setanswer
+ssh_userauth_list
+ssh_userauth_none
+ssh_userauth_offer_pubkey
+ssh_userauth_password
+ssh_userauth_privatekey_file
+ssh_userauth_pubkey
+ssh_userauth_publickey
+ssh_userauth_publickey_auto
+ssh_userauth_try_publickey
+ssh_version
+ssh_write_knownhost
+string_burn
+string_copy
+string_data
+string_fill
+string_free
+string_from_char
+string_len
+string_new
+string_to_char

src/ABI/libssh-4.8.9.symbols

@@ -0,0 +1,421 @@
+_ssh_log
+buffer_free
+buffer_get
+buffer_get_len
+buffer_new
+channel_accept_x11
+channel_change_pty_size
+channel_close
+channel_forward_accept
+channel_forward_cancel
+channel_forward_listen
+channel_free
+channel_get_exit_status
+channel_get_session
+channel_is_closed
+channel_is_eof
+channel_is_open
+channel_new
+channel_open_forward
+channel_open_session
+channel_poll
+channel_read
+channel_read_buffer
+channel_read_nonblocking
+channel_request_env
+channel_request_exec
+channel_request_pty
+channel_request_pty_size
+channel_request_send_signal
+channel_request_sftp
+channel_request_shell
+channel_request_subsystem
+channel_request_x11
+channel_select
+channel_send_eof
+channel_set_blocking
+channel_write
+channel_write_stderr
+privatekey_free
+privatekey_from_file
+publickey_free
+publickey_from_file
+publickey_from_privatekey
+publickey_to_string
+sftp_async_read
+sftp_async_read_begin
+sftp_attributes_free
+sftp_canonicalize_path
+sftp_chmod
+sftp_chown
+sftp_client_message_free
+sftp_client_message_get_data
+sftp_client_message_get_filename
+sftp_client_message_get_flags
+sftp_client_message_get_submessage
+sftp_client_message_get_type
+sftp_client_message_set_filename
+sftp_close
+sftp_closedir
+sftp_dir_eof
+sftp_extension_supported
+sftp_extensions_get_count
+sftp_extensions_get_data
+sftp_extensions_get_name
+sftp_file_set_blocking
+sftp_file_set_nonblocking
+sftp_free
+sftp_fstat
+sftp_fstatvfs
+sftp_fsync
+sftp_get_client_message
+sftp_get_error
+sftp_handle
+sftp_handle_alloc
+sftp_handle_remove
+sftp_init
+sftp_lstat
+sftp_mkdir
+sftp_new
+sftp_new_channel
+sftp_open
+sftp_opendir
+sftp_read
+sftp_readdir
+sftp_readlink
+sftp_rename
+sftp_reply_attr
+sftp_reply_data
+sftp_reply_handle
+sftp_reply_name
+sftp_reply_names
+sftp_reply_names_add
+sftp_reply_status
+sftp_rewind
+sftp_rmdir
+sftp_seek
+sftp_seek64
+sftp_send_client_message
+sftp_server_free
+sftp_server_init
+sftp_server_new
+sftp_server_version
+sftp_setstat
+sftp_stat
+sftp_statvfs
+sftp_statvfs_free
+sftp_symlink
+sftp_tell
+sftp_tell64
+sftp_unlink
+sftp_utimes
+sftp_write
+ssh_accept
+ssh_add_channel_callbacks
+ssh_auth_list
+ssh_basename
+ssh_bind_accept
+ssh_bind_accept_fd
+ssh_bind_fd_toaccept
+ssh_bind_free
+ssh_bind_get_fd
+ssh_bind_listen
+ssh_bind_new
+ssh_bind_options_parse_config
+ssh_bind_options_set
+ssh_bind_set_blocking
+ssh_bind_set_callbacks
+ssh_bind_set_fd
+ssh_blocking_flush
+ssh_buffer_add_data
+ssh_buffer_free
+ssh_buffer_get
+ssh_buffer_get_data
+ssh_buffer_get_len
+ssh_buffer_new
+ssh_buffer_reinit
+ssh_channel_accept_forward
+ssh_channel_accept_x11
+ssh_channel_cancel_forward
+ssh_channel_change_pty_size
+ssh_channel_close
+ssh_channel_free
+ssh_channel_get_exit_status
+ssh_channel_get_session
+ssh_channel_is_closed
+ssh_channel_is_eof
+ssh_channel_is_open
+ssh_channel_listen_forward
+ssh_channel_new
+ssh_channel_open_auth_agent
+ssh_channel_open_forward
+ssh_channel_open_forward_unix
+ssh_channel_open_reverse_forward
+ssh_channel_open_session
+ssh_channel_open_x11
+ssh_channel_poll
+ssh_channel_poll_timeout
+ssh_channel_read
+ssh_channel_read_nonblocking
+ssh_channel_read_timeout
+ssh_channel_request_auth_agent
+ssh_channel_request_env
+ssh_channel_request_exec
+ssh_channel_request_pty
+ssh_channel_request_pty_size
+ssh_channel_request_send_break
+ssh_channel_request_send_exit_signal
+ssh_channel_request_send_exit_status
+ssh_channel_request_send_signal
+ssh_channel_request_sftp
+ssh_channel_request_shell
+ssh_channel_request_subsystem
+ssh_channel_request_x11
+ssh_channel_select
+ssh_channel_send_eof
+ssh_channel_set_blocking
+ssh_channel_set_counter
+ssh_channel_window_size
+ssh_channel_write
+ssh_channel_write_stderr
+ssh_clean_pubkey_hash
+ssh_connect
+ssh_connector_free
+ssh_connector_new
+ssh_connector_set_in_channel
+ssh_connector_set_in_fd
+ssh_connector_set_out_channel
+ssh_connector_set_out_fd
+ssh_copyright
+ssh_dirname
+ssh_disconnect
+ssh_dump_knownhost
+ssh_event_add_connector
+ssh_event_add_fd
+ssh_event_add_session
+ssh_event_dopoll
+ssh_event_free
+ssh_event_new
+ssh_event_remove_connector
+ssh_event_remove_fd
+ssh_event_remove_session
+ssh_execute_message_callbacks
+ssh_finalize
+ssh_forward_accept
+ssh_forward_cancel
+ssh_forward_listen
+ssh_free
+ssh_get_cipher_in
+ssh_get_cipher_out
+ssh_get_clientbanner
+ssh_get_disconnect_message
+ssh_get_error
+ssh_get_error_code
+ssh_get_fd
+ssh_get_fingerprint_hash
+ssh_get_hexa
+ssh_get_hmac_in
+ssh_get_hmac_out
+ssh_get_issue_banner
+ssh_get_kex_algo
+ssh_get_log_callback
+ssh_get_log_level
+ssh_get_log_userdata
+ssh_get_openssh_version
+ssh_get_poll_flags
+ssh_get_pubkey
+ssh_get_pubkey_hash
+ssh_get_publickey
+ssh_get_publickey_hash
+ssh_get_random
+ssh_get_server_publickey
+ssh_get_serverbanner
+ssh_get_status
+ssh_get_version
+ssh_getpass
+ssh_gssapi_get_creds
+ssh_gssapi_set_creds
+ssh_handle_key_exchange
+ssh_init
+ssh_is_blocking
+ssh_is_connected
+ssh_is_server_known
+ssh_key_cmp
+ssh_key_free
+ssh_key_is_private
+ssh_key_is_public
+ssh_key_new
+ssh_key_type
+ssh_key_type_from_name
+ssh_key_type_to_char
+ssh_known_hosts_parse_line
+ssh_knownhosts_entry_free
+ssh_log
+ssh_message_auth_interactive_request
+ssh_message_auth_kbdint_is_response
+ssh_message_auth_password
+ssh_message_auth_pubkey
+ssh_message_auth_publickey
+ssh_message_auth_publickey_state
+ssh_message_auth_reply_pk_ok
+ssh_message_auth_reply_pk_ok_simple
+ssh_message_auth_reply_success
+ssh_message_auth_set_methods
+ssh_message_auth_user
+ssh_message_channel_request_channel
+ssh_message_channel_request_command
+ssh_message_channel_request_env_name
+ssh_message_channel_request_env_value
+ssh_message_channel_request_open_destination
+ssh_message_channel_request_open_destination_port
+ssh_message_channel_request_open_originator
+ssh_message_channel_request_open_originator_port
+ssh_message_channel_request_open_reply_accept
+ssh_message_channel_request_open_reply_accept_channel
+ssh_message_channel_request_pty_height
+ssh_message_channel_request_pty_pxheight
+ssh_message_channel_request_pty_pxwidth
+ssh_message_channel_request_pty_term
+ssh_message_channel_request_pty_width
+ssh_message_channel_request_reply_success
+ssh_message_channel_request_subsystem
+ssh_message_channel_request_x11_auth_cookie
+ssh_message_channel_request_x11_auth_protocol
+ssh_message_channel_request_x11_screen_number
+ssh_message_channel_request_x11_single_connection
+ssh_message_free
+ssh_message_get
+ssh_message_global_request_address
+ssh_message_global_request_port
+ssh_message_global_request_reply_success
+ssh_message_reply_default
+ssh_message_retrieve
+ssh_message_service_reply_success
+ssh_message_service_service
+ssh_message_subtype
+ssh_message_type
+ssh_mkdir
+ssh_new
+ssh_options_copy
+ssh_options_get
+ssh_options_get_port
+ssh_options_getopt
+ssh_options_parse_config
+ssh_options_set
+ssh_pcap_file_close
+ssh_pcap_file_free
+ssh_pcap_file_new
+ssh_pcap_file_open
+ssh_pki_copy_cert_to_privkey
+ssh_pki_export_privkey_base64
+ssh_pki_export_privkey_file
+ssh_pki_export_privkey_to_pubkey
+ssh_pki_export_pubkey_base64
+ssh_pki_export_pubkey_file
+ssh_pki_generate
+ssh_pki_import_cert_base64
+ssh_pki_import_cert_file
+ssh_pki_import_privkey_base64
+ssh_pki_import_privkey_file
+ssh_pki_import_pubkey_base64
+ssh_pki_import_pubkey_file
+ssh_pki_key_ecdsa_name
+ssh_print_hash
+ssh_print_hexa
+ssh_privatekey_type
+ssh_publickey_to_file
+ssh_remove_channel_callbacks
+ssh_scp_accept_request
+ssh_scp_close
+ssh_scp_deny_request
+ssh_scp_free
+ssh_scp_init
+ssh_scp_leave_directory
+ssh_scp_new
+ssh_scp_pull_request
+ssh_scp_push_directory
+ssh_scp_push_file
+ssh_scp_push_file64
+ssh_scp_read
+ssh_scp_request_get_filename
+ssh_scp_request_get_permissions
+ssh_scp_request_get_size
+ssh_scp_request_get_size64
+ssh_scp_request_get_warning
+ssh_scp_write
+ssh_select
+ssh_send_debug
+ssh_send_ignore
+ssh_send_keepalive
+ssh_server_init_kex
+ssh_service_request
+ssh_session_export_known_hosts_entry
+ssh_session_get_known_hosts_entry
+ssh_session_has_known_hosts_entry
+ssh_session_is_known_server
+ssh_session_update_known_hosts
+ssh_set_agent_channel
+ssh_set_agent_socket
+ssh_set_auth_methods
+ssh_set_blocking
+ssh_set_callbacks
+ssh_set_channel_callbacks
+ssh_set_counters
+ssh_set_fd_except
+ssh_set_fd_toread
+ssh_set_fd_towrite
+ssh_set_log_callback
+ssh_set_log_level
+ssh_set_log_userdata
+ssh_set_message_callback
+ssh_set_pcap_file
+ssh_set_server_callbacks
+ssh_silent_disconnect
+ssh_string_burn
+ssh_string_copy
+ssh_string_data
+ssh_string_fill
+ssh_string_free
+ssh_string_free_char
+ssh_string_from_char
+ssh_string_get_char
+ssh_string_len
+ssh_string_new
+ssh_string_to_char
+ssh_threads_get_default
+ssh_threads_get_noop
+ssh_threads_get_pthread
+ssh_threads_set_callbacks
+ssh_try_publickey_from_file
+ssh_userauth_agent
+ssh_userauth_agent_pubkey
+ssh_userauth_autopubkey
+ssh_userauth_gssapi
+ssh_userauth_kbdint
+ssh_userauth_kbdint_getanswer
+ssh_userauth_kbdint_getinstruction
+ssh_userauth_kbdint_getname
+ssh_userauth_kbdint_getnanswers
+ssh_userauth_kbdint_getnprompts
+ssh_userauth_kbdint_getprompt
+ssh_userauth_kbdint_setanswer
+ssh_userauth_list
+ssh_userauth_none
+ssh_userauth_offer_pubkey
+ssh_userauth_password
+ssh_userauth_privatekey_file
+ssh_userauth_pubkey
+ssh_userauth_publickey
+ssh_userauth_publickey_auto
+ssh_userauth_try_publickey
+ssh_version
+ssh_write_knownhost
+string_burn
+string_copy
+string_data
+string_fill
+string_free
+string_from_char
+string_len
+string_new
+string_to_char

src/CMakeLists.txt

@@ -9,13 +9,6 @@ set(LIBSSH_LINK_LIBRARIES
   ${LIBSSH_REQUIRED_LIBRARIES}
 )
 
-if (WIN32)
-  set(LIBSSH_LINK_LIBRARIES
-    ${LIBSSH_LINK_LIBRARIES}
-    ws2_32
-  )
-endif (WIN32)
-
 if (OPENSSL_CRYPTO_LIBRARIES)
   set(LIBSSH_PRIVATE_INCLUDE_DIRS
     ${LIBSSH_PRIVATE_INCLUDE_DIRS}
@@ -93,6 +86,16 @@ if (MINGW AND Threads_FOUND)
   )
 endif()
 
+# This needs to be last for mingw to build
+# https://gitlab.com/libssh/libssh-mirror/-/issues/84
+if (WIN32)
+  set(LIBSSH_LINK_LIBRARIES
+    ${LIBSSH_LINK_LIBRARIES}
+    iphlpapi
+    ws2_32
+  )
+endif (WIN32)
+
 if (BUILD_STATIC_LIB)
   set(LIBSSH_STATIC_LIBRARY
     ssh_static

src/channels.c

@@ -3403,9 +3403,15 @@ int ssh_channel_select(ssh_channel *readchans, ssh_channel *writechans,
     firstround=0;
   } while(1);
 
-  memcpy(readchans, rchans, (count_ptrs(rchans) + 1) * sizeof(ssh_channel ));
-  memcpy(writechans, wchans, (count_ptrs(wchans) + 1) * sizeof(ssh_channel ));
-  memcpy(exceptchans, echans, (count_ptrs(echans) + 1) * sizeof(ssh_channel ));
+  if (readchans != &dummy) {
+      memcpy(readchans, rchans, (count_ptrs(rchans) + 1) * sizeof(ssh_channel));
+  }
+  if (writechans != &dummy) {
+      memcpy(writechans, wchans, (count_ptrs(wchans) + 1) * sizeof(ssh_channel));
+  }
+  if (exceptchans != &dummy) {
+      memcpy(exceptchans, echans, (count_ptrs(echans) + 1) * sizeof(ssh_channel));
+  }
   SAFE_FREE(rchans);
   SAFE_FREE(wchans);
   SAFE_FREE(echans);

src/client.c

@@ -243,10 +243,13 @@ end:
  * @warning this function returning is no proof that DH handshake is
  * completed
  */
-static int dh_handshake(ssh_session session) {
-
+int dh_handshake(ssh_session session)
+{
   int rc = SSH_AGAIN;
 
+  SSH_LOG(SSH_LOG_TRACE, "dh_handshake_state = %d, kex_type = %d",
+          session->dh_handshake_state,  session->next_crypto->kex_type);
+
   switch (session->dh_handshake_state) {
     case DH_STATE_INIT:
       switch(session->next_crypto->kex_type){
@@ -386,95 +389,101 @@ static void ssh_client_connection_callback(ssh_session session)
 {
     int rc;
 
-    switch(session->session_state) {
-        case SSH_SESSION_STATE_NONE:
-        case SSH_SESSION_STATE_CONNECTING:
-            break;
-        case SSH_SESSION_STATE_SOCKET_CONNECTED:
-            ssh_set_fd_towrite(session);
-            ssh_send_banner(session, 0);
+    SSH_LOG(SSH_LOG_DEBUG, "session_state=%d", session->session_state);
 
-            break;
-        case SSH_SESSION_STATE_BANNER_RECEIVED:
-            if (session->serverbanner == NULL) {
-                goto error;
-            }
-            set_status(session, 0.4f);
-            SSH_LOG(SSH_LOG_PROTOCOL,
-                    "SSH server banner: %s", session->serverbanner);
+    switch (session->session_state) {
+    case SSH_SESSION_STATE_NONE:
+    case SSH_SESSION_STATE_CONNECTING:
+        break;
+    case SSH_SESSION_STATE_SOCKET_CONNECTED:
+        ssh_set_fd_towrite(session);
+        ssh_send_banner(session, 0);
 
-            /* Here we analyze the different protocols the server allows. */
-            rc = ssh_analyze_banner(session, 0);
-            if (rc < 0) {
-                ssh_set_error(session, SSH_FATAL,
-                        "No version of SSH protocol usable (banner: %s)",
-                        session->serverbanner);
-                goto error;
-            }
+        break;
+    case SSH_SESSION_STATE_BANNER_RECEIVED:
+        if (session->serverbanner == NULL) {
+            goto error;
+        }
+        set_status(session, 0.4f);
+        SSH_LOG(SSH_LOG_PROTOCOL,
+                "SSH server banner: %s", session->serverbanner);
 
-            ssh_packet_register_socket_callback(session, session->socket);
+        /* Here we analyze the different protocols the server allows. */
+        rc = ssh_analyze_banner(session, 0);
+        if (rc < 0) {
+            ssh_set_error(session, SSH_FATAL,
+                          "No version of SSH protocol usable (banner: %s)",
+                          session->serverbanner);
+            goto error;
+        }
 
-            ssh_packet_set_default_callbacks(session);
-            session->session_state = SSH_SESSION_STATE_INITIAL_KEX;
+        ssh_packet_register_socket_callback(session, session->socket);
+
+        ssh_packet_set_default_callbacks(session);
+        session->session_state = SSH_SESSION_STATE_INITIAL_KEX;
+        rc = ssh_set_client_kex(session);
+        if (rc != SSH_OK) {
+            goto error;
+        }
+        rc = ssh_send_kex(session);
+        if (rc < 0) {
+            goto error;
+        }
+        set_status(session, 0.5f);
+
+        break;
+    case SSH_SESSION_STATE_INITIAL_KEX:
+        /* TODO: This state should disappear in favor of get_key handle */
+        break;
+    case SSH_SESSION_STATE_KEXINIT_RECEIVED:
+        set_status(session, 0.6f);
+        ssh_list_kex(&session->next_crypto->server_kex);
+        if ((session->flags & SSH_SESSION_FLAG_KEXINIT_SENT) == 0) {
+            /* in rekeying state if next_crypto client_kex might be empty */
             rc = ssh_set_client_kex(session);
             if (rc != SSH_OK) {
                 goto error;
             }
-            rc = ssh_send_kex(session, 0);
+            rc = ssh_send_kex(session);
             if (rc < 0) {
                 goto error;
             }
-            set_status(session, 0.5f);
-
-            break;
-        case SSH_SESSION_STATE_INITIAL_KEX:
-            /* TODO: This state should disappear in favor of get_key handle */
-            break;
-        case SSH_SESSION_STATE_KEXINIT_RECEIVED:
-            set_status(session,0.6f);
-            ssh_list_kex(&session->next_crypto->server_kex);
-            if (session->next_crypto->client_kex.methods[0] == NULL) {
-                /* in rekeying state if next_crypto client_kex is empty */
-                rc = ssh_set_client_kex(session);
-                if (rc != SSH_OK) {
-                    goto error;
-                }
-                rc = ssh_send_kex(session, 0);
-                if (rc < 0) {
-                    goto error;
-                }
-            }
-            if (ssh_kex_select_methods(session) == SSH_ERROR)
-                goto error;
-            set_status(session,0.8f);
-            session->session_state=SSH_SESSION_STATE_DH;
-            if (dh_handshake(session) == SSH_ERROR) {
-                goto error;
-            }
-            FALL_THROUGH;
-        case SSH_SESSION_STATE_DH:
-            if(session->dh_handshake_state==DH_STATE_FINISHED){
-                set_status(session,1.0f);
-                session->connected = 1;
-                if (session->flags & SSH_SESSION_FLAG_AUTHENTICATED)
-                    session->session_state = SSH_SESSION_STATE_AUTHENTICATED;
-                else
-                    session->session_state=SSH_SESSION_STATE_AUTHENTICATING;
-            }
-            break;
-        case SSH_SESSION_STATE_AUTHENTICATING:
-            break;
-        case SSH_SESSION_STATE_ERROR:
+        }
+        if (ssh_kex_select_methods(session) == SSH_ERROR)
             goto error;
-        default:
-            ssh_set_error(session,SSH_FATAL,"Invalid state %d",session->session_state);
+        set_status(session, 0.8f);
+        session->session_state = SSH_SESSION_STATE_DH;
+
+        /* If the init packet was already sent in previous step, this will be no
+         * operation */
+        if (dh_handshake(session) == SSH_ERROR) {
+            goto error;
+        }
+        FALL_THROUGH;
+    case SSH_SESSION_STATE_DH:
+        if (session->dh_handshake_state == DH_STATE_FINISHED) {
+            set_status(session, 1.0f);
+            session->connected = 1;
+            if (session->flags & SSH_SESSION_FLAG_AUTHENTICATED)
+                session->session_state = SSH_SESSION_STATE_AUTHENTICATED;
+            else
+                session->session_state=SSH_SESSION_STATE_AUTHENTICATING;
+        }
+        break;
+    case SSH_SESSION_STATE_AUTHENTICATING:
+        break;
+    case SSH_SESSION_STATE_ERROR:
+        goto error;
+    default:
+        ssh_set_error(session, SSH_FATAL, "Invalid state %d",
+                      session->session_state);
     }
 
     return;
 error:
     ssh_socket_close(session->socket);
     session->alive = 0;
-    session->session_state=SSH_SESSION_STATE_ERROR;
+    session->session_state = SSH_SESSION_STATE_ERROR;
 
 }
 

src/config_parser.c

@@ -30,6 +30,7 @@
 
 #include "libssh/config_parser.h"
 #include "libssh/priv.h"
+#include "libssh/misc.h"
 
 char *ssh_config_get_cmd(char **str)
 {
@@ -139,6 +140,7 @@ int ssh_config_parse_uri(const char *tok,
 {
     char *endp = NULL;
     long port_n;
+    int rc;
 
     /* Sanitize inputs */
     if (username != NULL) {
@@ -152,7 +154,7 @@ int ssh_config_parse_uri(const char *tok,
     }
 
     /* Username part (optional) */
-    endp = strchr(tok, '@');
+    endp = strrchr(tok, '@');
     if (endp != NULL) {
         /* Zero-length username is not valid */
         if (tok == endp) {
@@ -196,6 +198,14 @@ int ssh_config_parse_uri(const char *tok,
         if (*hostname == NULL) {
             goto error;
         }
+        /* if not an ip, check syntax */
+        rc = ssh_is_ipaddr(*hostname);
+        if (rc == 0) {
+            rc = ssh_check_hostname_syntax(*hostname);
+            if (rc != SSH_OK) {
+                goto error;
+            }
+        }
     }
     /* Skip also the closing bracket */
     if (*endp == ']') {

src/connect.c

@@ -136,7 +136,7 @@ static int getai(const char *host, int port, struct addrinfo **ai)
 #endif
     }
 
-    if (ssh_is_ipaddr(host)) {
+    if (ssh_is_ipaddr(host) == 1) {
         /* this is an IP address */
         SSH_LOG(SSH_LOG_PACKET, "host %s matches an IP address", host);
         hints.ai_flags |= AI_NUMERICHOST;

src/curve25519.c

@@ -172,6 +172,11 @@ int ssh_client_curve25519_init(ssh_session session)
     return rc;
 }
 
+void ssh_client_curve25519_remove_callbacks(ssh_session session)
+{
+    ssh_packet_remove_callbacks(session, &ssh_curve25519_client_callbacks);
+}
+
 static int ssh_curve25519_build_k(ssh_session session)
 {
     ssh_curve25519_pubkey k;
@@ -285,7 +290,7 @@ static SSH_PACKET_CALLBACK(ssh_packet_client_curve25519_reply){
   (void)type;
   (void)user;
 
-  ssh_packet_remove_callbacks(session, &ssh_curve25519_client_callbacks);
+  ssh_client_curve25519_remove_callbacks(session);
 
   pubkey_blob = ssh_buffer_get_ssh_string(packet);
   if (pubkey_blob == NULL) {
@@ -330,16 +335,10 @@ static SSH_PACKET_CALLBACK(ssh_packet_client_curve25519_reply){
   }
 
   /* Send the MSG_NEWKEYS */
-  if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
-    goto error;
-  }
-
-  rc=ssh_packet_send(session);
+  rc = ssh_packet_send_newkeys(session);
   if (rc == SSH_ERROR) {
     goto error;
   }
-
-  SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
   session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
 
   return SSH_PACKET_USED;
@@ -497,18 +496,13 @@ static SSH_PACKET_CALLBACK(ssh_packet_server_curve25519_init){
         return SSH_ERROR;
     }
 
-    /* Send the MSG_NEWKEYS */
-    rc = ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS);
-    if (rc < 0) {
-        goto error;
-    }
-
     session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
-    rc = ssh_packet_send(session);
+
+    /* Send the MSG_NEWKEYS */
+    rc = ssh_packet_send_newkeys(session);
     if (rc == SSH_ERROR) {
         goto error;
     }
-    SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
 
     return SSH_PACKET_USED;
 error:

src/dh-gex.c

@@ -238,6 +238,11 @@ error:
     return SSH_PACKET_USED;
 }
 
+void ssh_client_dhgex_remove_callbacks(ssh_session session)
+{
+    ssh_packet_remove_callbacks(session, &ssh_dhgex_client_callbacks);
+}
+
 static SSH_PACKET_CALLBACK(ssh_packet_client_dhgex_reply)
 {
     struct ssh_crypto_struct *crypto=session->next_crypto;
@@ -248,7 +253,7 @@ static SSH_PACKET_CALLBACK(ssh_packet_client_dhgex_reply)
     (void)user;
     SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_KEX_DH_GEX_REPLY received");
 
-    ssh_packet_remove_callbacks(session, &ssh_dhgex_client_callbacks);
+    ssh_client_dhgex_remove_callbacks(session);
     rc = ssh_buffer_unpack(packet,
                            "SBS",
                            &pubkey_blob, &server_pubkey,
@@ -282,15 +287,10 @@ static SSH_PACKET_CALLBACK(ssh_packet_client_dhgex_reply)
     }
 
     /* Send the MSG_NEWKEYS */
-    if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
-        goto error;
-    }
-
-    rc = ssh_packet_send(session);
+    rc = ssh_packet_send_newkeys(session);
     if (rc == SSH_ERROR) {
         goto error;
     }
-    SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
     session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
 
     return SSH_PACKET_USED;

src/dh.c

@@ -342,6 +342,11 @@ error:
   return SSH_ERROR;
 }
 
+void ssh_client_dh_remove_callbacks(ssh_session session)
+{
+    ssh_packet_remove_callbacks(session, &ssh_dh_client_callbacks);
+}
+
 SSH_PACKET_CALLBACK(ssh_packet_client_dh_reply){
   struct ssh_crypto_struct *crypto=session->next_crypto;
   ssh_string pubkey_blob = NULL;
@@ -351,7 +356,7 @@ SSH_PACKET_CALLBACK(ssh_packet_client_dh_reply){
   (void)type;
   (void)user;
 
-  ssh_packet_remove_callbacks(session, &ssh_dh_client_callbacks);
+  ssh_client_dh_remove_callbacks(session);
 
   rc = ssh_buffer_unpack(packet, "SBS", &pubkey_blob, &server_pubkey,
           &crypto->dh_server_signature);
@@ -381,16 +386,10 @@ SSH_PACKET_CALLBACK(ssh_packet_client_dh_reply){
   }
 
   /* Send the MSG_NEWKEYS */
-  if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
-    goto error;
-  }
-
-  rc=ssh_packet_send(session);
+  rc = ssh_packet_send_newkeys(session);
   if (rc == SSH_ERROR) {
     goto error;
   }
-
-  SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
   session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
   return SSH_PACKET_USED;
 error:
@@ -527,15 +526,12 @@ int ssh_server_dh_process_init(ssh_session session, ssh_buffer packet)
     }
     SSH_LOG(SSH_LOG_DEBUG, "Sent KEX_DH_[GEX]_REPLY");
 
-    if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
-        ssh_buffer_reinit(session->out_buffer);
-        goto error;
-    }
     session->dh_handshake_state=DH_STATE_NEWKEYS_SENT;
-    if (ssh_packet_send(session) == SSH_ERROR) {
+    /* Send the MSG_NEWKEYS */
+    rc = ssh_packet_send_newkeys(session);
+    if (rc == SSH_ERROR) {
         goto error;
     }
-    SSH_LOG(SSH_LOG_PACKET, "SSH_MSG_NEWKEYS sent");
 
     return SSH_OK;
 error:

src/ecdh.c

@@ -43,6 +43,11 @@ struct ssh_packet_callbacks_struct ssh_ecdh_client_callbacks = {
     .user = NULL
 };
 
+void ssh_client_ecdh_remove_callbacks(ssh_session session)
+{
+    ssh_packet_remove_callbacks(session, &ssh_ecdh_client_callbacks);
+}
+
 /** @internal
  * @brief parses a SSH_MSG_KEX_ECDH_REPLY packet and sends back
  * a SSH_MSG_NEWKEYS
@@ -55,7 +60,7 @@ SSH_PACKET_CALLBACK(ssh_packet_client_ecdh_reply){
   (void)type;
   (void)user;
 
-  ssh_packet_remove_callbacks(session, &ssh_ecdh_client_callbacks);
+  ssh_client_ecdh_remove_callbacks(session);
   pubkey_blob = ssh_buffer_get_ssh_string(packet);
   if (pubkey_blob == NULL) {
     ssh_set_error(session,SSH_FATAL, "No public key in packet");
@@ -88,16 +93,10 @@ SSH_PACKET_CALLBACK(ssh_packet_client_ecdh_reply){
   }
 
   /* Send the MSG_NEWKEYS */
-  if (ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS) < 0) {
-    goto error;
-  }
-
-  rc=ssh_packet_send(session);
+  rc = ssh_packet_send_newkeys(session);
   if (rc == SSH_ERROR) {
     goto error;
   }
-
-  SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
   session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
 
   return SSH_PACKET_USED;

src/ecdh_crypto.c

@@ -323,18 +323,12 @@ SSH_PACKET_CALLBACK(ssh_packet_server_ecdh_init){
         goto error;
     }
 
-    /* Send the MSG_NEWKEYS */
-    rc = ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS);
-    if (rc < 0) {
-        goto error;
-    }
-
     session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
-    rc = ssh_packet_send(session);
-    if (rc == SSH_ERROR){
+    /* Send the MSG_NEWKEYS */
+    rc = ssh_packet_send_newkeys(session);
+    if (rc == SSH_ERROR) {
         goto error;
     }
-    SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
 
     return SSH_PACKET_USED;
 error:

src/ecdh_gcrypt.c

@@ -372,17 +372,13 @@ SSH_PACKET_CALLBACK(ssh_packet_server_ecdh_init){
         goto out;
     }
 
-
+    session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
     /* Send the MSG_NEWKEYS */
-    rc = ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS);
-    if (rc != SSH_OK) {
+    rc = ssh_packet_send_newkeys(session);
+    if (rc == SSH_ERROR) {
         goto out;
     }
 
-    session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
-    rc = ssh_packet_send(session);
-    SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
-
  out:
     gcry_sexp_release(param);
     gcry_sexp_release(key);

src/ecdh_mbedcrypto.c

@@ -300,16 +300,13 @@ SSH_PACKET_CALLBACK(ssh_packet_server_ecdh_init){
         goto out;
     }
 
-    rc = ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS);
-    if (rc < 0) {
-        rc = SSH_ERROR;
+    session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
+    /* Send the MSG_NEWKEYS */
+    rc = ssh_packet_send_newkeys(session);
+    if (rc == SSH_ERROR) {
         goto out;
     }
 
-    session->dh_handshake_state = DH_STATE_NEWKEYS_SENT;
-    rc = ssh_packet_send(session);
-    SSH_LOG(SSH_LOG_PROTOCOL, "SSH_MSG_NEWKEYS sent");
-
 out:
     mbedtls_ecp_group_free(&grp);
     if (rc == SSH_ERROR) {

src/gssapi.c

@@ -223,6 +223,7 @@ int ssh_gssapi_handle_userauth(ssh_session session, const char *user, uint32_t n
                              "indicate mechs",
                              maj_stat,
                              min_stat);
+        gss_release_oid_set(&min_stat, &both_supported);
         return SSH_ERROR;
     }
 
@@ -259,8 +260,10 @@ int ssh_gssapi_handle_userauth(ssh_session session, const char *user, uint32_t n
         return SSH_OK;
     }
     /* from now we have room for context */
-    if (ssh_gssapi_init(session) == SSH_ERROR)
+    if (ssh_gssapi_init(session) == SSH_ERROR) {
+        gss_release_oid_set(&min_stat, &both_supported);
         return SSH_ERROR;
+    }
 
     name_buf.value = service_name;
     name_buf.length = strlen(name_buf.value) + 1;
@@ -272,6 +275,7 @@ int ssh_gssapi_handle_userauth(ssh_session session, const char *user, uint32_t n
                              "importing name",
                              maj_stat,
                              min_stat);
+        gss_release_oid_set(&min_stat, &both_supported);
         return -1;
     }
 
@@ -338,6 +342,7 @@ static char *ssh_gssapi_name_to_char(gss_name_t name){
                          min_stat);
     ptr = malloc(buffer.length + 1);
     if (ptr == NULL) {
+        gss_release_buffer(&min_stat, &buffer);
         return NULL;
     }
     memcpy(ptr, buffer.value, buffer.length);
@@ -421,6 +426,7 @@ SSH_PACKET_CALLBACK(ssh_packet_userauth_gssapi_token_server){
                              "Gssapi error",
                              maj_stat,
                              min_stat);
+        gss_release_buffer(&min_stat, &output_token);
         ssh_auth_reply_default(session,0);
         ssh_gssapi_free(session);
         session->gssapi=NULL;
@@ -438,6 +444,9 @@ SSH_PACKET_CALLBACK(ssh_packet_userauth_gssapi_token_server){
                         (size_t)output_token.length, output_token.value);
         ssh_packet_send(session);
     }
+
+    gss_release_buffer(&min_stat, &output_token);
+
     if(maj_stat == GSS_S_COMPLETE){
         session->gssapi->state = SSH_GSSAPI_STATE_RCV_MIC;
     }
@@ -638,7 +647,7 @@ fail:
 static int ssh_gssapi_match(ssh_session session, gss_OID_set *valid_oids)
 {
     OM_uint32 maj_stat, min_stat, lifetime;
-    gss_OID_set actual_mechs;
+    gss_OID_set actual_mechs = GSS_C_NO_OID_SET;
     gss_buffer_desc namebuf;
     gss_name_t client_id = GSS_C_NO_NAME;
     gss_OID oid;
@@ -700,6 +709,7 @@ static int ssh_gssapi_match(ssh_session session, gss_OID_set *valid_oids)
     ret = SSH_OK;
 
 end:
+    gss_release_oid_set(&min_stat, &actual_mechs);
     gss_release_name(&min_stat, &client_id);
     return ret;
 }
@@ -713,7 +723,7 @@ end:
  */
 int ssh_gssapi_auth_mic(ssh_session session){
     size_t i;
-    gss_OID_set selected; /* oid selected for authentication */
+    gss_OID_set selected = GSS_C_NO_OID_SET; /* oid selected for authentication */
     ssh_string *oids = NULL;
     int rc;
     size_t n_oids = 0;
@@ -790,6 +800,8 @@ out:
         SSH_STRING_FREE(oids[i]);
     }
     free(oids);
+    gss_release_oid_set(&min_stat, &selected);
+
     if (rc != SSH_ERROR) {
         return SSH_AUTH_AGAIN;
     }
@@ -893,6 +905,8 @@ SSH_PACKET_CALLBACK(ssh_packet_userauth_gssapi_response){
         ssh_packet_send(session);
         session->auth.state = SSH_AUTH_STATE_GSSAPI_TOKEN;
     }
+
+    gss_release_buffer(&min_stat, &output_token);
     return SSH_PACKET_USED;
 
 error:
@@ -921,9 +935,11 @@ static int ssh_gssapi_send_mic(ssh_session session){
 
     maj_stat = gss_get_mic(&min_stat,session->gssapi->ctx, GSS_C_QOP_DEFAULT,
                            &mic_buf, &mic_token_buf);
+
+    SSH_BUFFER_FREE(mic_buffer);
+
     if (GSS_ERROR(maj_stat)){
-        SSH_BUFFER_FREE(mic_buffer);
-        ssh_gssapi_log_error(SSH_LOG_PROTOCOL,
+        ssh_gssapi_log_error(SSH_LOG_DEBUG,
                              "generating MIC",
                              maj_stat,
                              min_stat);
@@ -935,8 +951,10 @@ static int ssh_gssapi_send_mic(ssh_session session){
                          SSH2_MSG_USERAUTH_GSSAPI_MIC,
                          mic_token_buf.length,
                          (size_t)mic_token_buf.length, mic_token_buf.value);
+
+    gss_release_buffer(&min_stat, &mic_token_buf);
+
     if (rc != SSH_OK) {
-        SSH_BUFFER_FREE(mic_buffer);
         ssh_set_error_oom(session);
         return SSH_ERROR;
     }
@@ -1005,6 +1023,8 @@ SSH_PACKET_CALLBACK(ssh_packet_userauth_gssapi_token_client){
         ssh_packet_send(session);
     }
 
+    gss_release_buffer(&min_stat, &output_token);
+
     if (maj_stat == GSS_S_COMPLETE) {
         ssh_gssapi_send_mic(session);
         session->auth.state = SSH_AUTH_STATE_GSSAPI_MIC_SENT;

src/init.c

@@ -269,7 +269,7 @@ BOOL WINAPI DllMain(HINSTANCE hinstDLL,
  *
  * @see ssh_init()
  */
-bool is_ssh_initialized() {
+bool is_ssh_initialized(void) {
 
     bool is_initialized = false;
 

src/kdf.c

@@ -58,65 +58,102 @@ static ssh_mac_ctx ssh_mac_ctx_init(enum ssh_kdf_digest type)
     }
 
     ctx->digest_type = type;
-    switch(type){
+    switch (type) {
     case SSH_KDF_SHA1:
         ctx->ctx.sha1_ctx = sha1_init();
+        if (ctx->ctx.sha1_ctx == NULL) {
+            goto err;
+        }
         return ctx;
     case SSH_KDF_SHA256:
         ctx->ctx.sha256_ctx = sha256_init();
+        if (ctx->ctx.sha256_ctx == NULL) {
+            goto err;
+        }
         return ctx;
     case SSH_KDF_SHA384:
         ctx->ctx.sha384_ctx = sha384_init();
+        if (ctx->ctx.sha384_ctx == NULL) {
+            goto err;
+        }
         return ctx;
     case SSH_KDF_SHA512:
         ctx->ctx.sha512_ctx = sha512_init();
+        if (ctx->ctx.sha512_ctx == NULL) {
+            goto err;
+        }
         return ctx;
-    default:
-        SAFE_FREE(ctx);
-        return NULL;
     }
+err:
+    SAFE_FREE(ctx);
+    return NULL;
 }
 
-static void ssh_mac_update(ssh_mac_ctx ctx, const void *data, size_t len)
+static void ssh_mac_ctx_free(ssh_mac_ctx ctx)
 {
-    switch(ctx->digest_type){
-    case SSH_KDF_SHA1:
-        sha1_update(ctx->ctx.sha1_ctx, data, len);
-        break;
-    case SSH_KDF_SHA256:
-        sha256_update(ctx->ctx.sha256_ctx, data, len);
-        break;
-    case SSH_KDF_SHA384:
-        sha384_update(ctx->ctx.sha384_ctx, data, len);
-        break;
-    case SSH_KDF_SHA512:
-        sha512_update(ctx->ctx.sha512_ctx, data, len);
-        break;
+    if (ctx == NULL) {
+        return;
     }
-}
 
-static void ssh_mac_final(unsigned char *md, ssh_mac_ctx ctx)
-{
-    switch(ctx->digest_type){
+    switch (ctx->digest_type) {
     case SSH_KDF_SHA1:
-        sha1_final(md,ctx->ctx.sha1_ctx);
+        sha1_ctx_free(ctx->ctx.sha1_ctx);
         break;
     case SSH_KDF_SHA256:
-        sha256_final(md,ctx->ctx.sha256_ctx);
+        sha256_ctx_free(ctx->ctx.sha256_ctx);
         break;
     case SSH_KDF_SHA384:
-        sha384_final(md,ctx->ctx.sha384_ctx);
+        sha384_ctx_free(ctx->ctx.sha384_ctx);
         break;
     case SSH_KDF_SHA512:
-        sha512_final(md,ctx->ctx.sha512_ctx);
+        sha512_ctx_free(ctx->ctx.sha512_ctx);
         break;
     }
     SAFE_FREE(ctx);
 }
 
+static int ssh_mac_update(ssh_mac_ctx ctx, const void *data, size_t len)
+{
+    switch (ctx->digest_type) {
+    case SSH_KDF_SHA1:
+        return sha1_update(ctx->ctx.sha1_ctx, data, len);
+    case SSH_KDF_SHA256:
+        return sha256_update(ctx->ctx.sha256_ctx, data, len);
+    case SSH_KDF_SHA384:
+        return sha384_update(ctx->ctx.sha384_ctx, data, len);
+    case SSH_KDF_SHA512:
+        return sha512_update(ctx->ctx.sha512_ctx, data, len);
+    }
+    return SSH_ERROR;
+}
+
+static int ssh_mac_final(unsigned char *md, ssh_mac_ctx ctx)
+{
+    int rc = SSH_ERROR;
+
+    switch (ctx->digest_type) {
+    case SSH_KDF_SHA1:
+        rc = sha1_final(md, ctx->ctx.sha1_ctx);
+        break;
+    case SSH_KDF_SHA256:
+        rc = sha256_final(md, ctx->ctx.sha256_ctx);
+        break;
+    case SSH_KDF_SHA384:
+        rc = sha384_final(md, ctx->ctx.sha384_ctx);
+        break;
+    case SSH_KDF_SHA512:
+        rc = sha512_final(md, ctx->ctx.sha512_ctx);
+        break;
+    }
+    SAFE_FREE(ctx);
+    return rc;
+}
+
 int sshkdf_derive_key(struct ssh_crypto_struct *crypto,
-                      unsigned char *key, size_t key_len,
-                      int key_type, unsigned char *output,
+                      unsigned char *key, 
+                      size_t key_len,
+                      int key_type, 
+                      unsigned char *output,
                       size_t requested_len)
 {
     /* Can't use VLAs with Visual Studio, so allocate the biggest
@@ -125,6 +162,7 @@ int sshkdf_derive_key(struct ssh_crypto_struct *crypto,
     size_t output_len = crypto->digest_len;
     char letter = key_type;
     ssh_mac_ctx ctx;
+    int rc;
 
     if (DIGEST_MAX_LEN < crypto->digest_len) {
         return -1;
@@ -135,11 +173,30 @@ int sshkdf_derive_key(struct ssh_crypto_struct *crypto,
         return -1;
     }
 
-    ssh_mac_update(ctx, key, key_len);
-    ssh_mac_update(ctx, crypto->secret_hash, crypto->digest_len);
-    ssh_mac_update(ctx, &letter, 1);
-    ssh_mac_update(ctx, crypto->session_id, crypto->session_id_len);
-    ssh_mac_final(digest, ctx);
+    rc = ssh_mac_update(ctx, key, key_len);
+    if (rc != SSH_OK) {
+        ssh_mac_ctx_free(ctx);
+        return -1;
+    }
+    rc = ssh_mac_update(ctx, crypto->secret_hash, crypto->digest_len);
+    if (rc != SSH_OK) {
+        ssh_mac_ctx_free(ctx);
+        return -1;
+    }
+    rc = ssh_mac_update(ctx, &letter, 1);
+    if (rc != SSH_OK) {
+        ssh_mac_ctx_free(ctx);
+        return -1;
+    }
+    rc = ssh_mac_update(ctx, crypto->session_id, crypto->session_id_len);
+    if (rc != SSH_OK) {
+        ssh_mac_ctx_free(ctx);
+        return -1;
+    }
+    rc = ssh_mac_final(digest, ctx);
+    if (rc != SSH_OK) {
+        return -1;
+    }
 
     if (requested_len < output_len) {
         output_len = requested_len;
@@ -151,10 +208,25 @@ int sshkdf_derive_key(struct ssh_crypto_struct *crypto,
         if (ctx == NULL) {
             return -1;
         }
-        ssh_mac_update(ctx, key, key_len);
-        ssh_mac_update(ctx, crypto->secret_hash, crypto->digest_len);
-        ssh_mac_update(ctx, output, output_len);
-        ssh_mac_final(digest, ctx);
+        rc = ssh_mac_update(ctx, key, key_len);
+        if (rc != SSH_OK) {
+            ssh_mac_ctx_free(ctx);
+            return -1;
+        }
+        rc = ssh_mac_update(ctx, crypto->secret_hash, crypto->digest_len);
+        if (rc != SSH_OK) {
+            ssh_mac_ctx_free(ctx);
+            return -1;
+        }
+        rc = ssh_mac_update(ctx, output, output_len);
+        if (rc != SSH_OK) {
+            ssh_mac_ctx_free(ctx);
+            return -1;
+        }
+        rc = ssh_mac_final(digest, ctx);
+        if (rc != SSH_OK) {
+            return -1;
+        }
         if (requested_len < output_len + crypto->digest_len) {
             memcpy(output + output_len, digest, requested_len - output_len);
         } else {

src/kex.c

@@ -28,6 +28,7 @@
 #include <stdio.h>
 #include <stdbool.h>
 
+#include "libssh/libssh.h"
 #include "libssh/priv.h"
 #include "libssh/buffer.h"
 #include "libssh/dh.h"
@@ -162,6 +163,9 @@
 
 /* RFC 8308 */
 #define KEX_EXTENSION_CLIENT "ext-info-c"
+/* Strict kex mitigation against CVE-2023-48795 */
+#define KEX_STRICT_CLIENT "kex-strict-c-v00@openssh.com"
+#define KEX_STRICT_SERVER "kex-strict-s-v00@openssh.com"
 
 /* Allowed algorithms in FIPS mode */
 #define FIPS_ALLOWED_CIPHERS "aes256-gcm@openssh.com,"\
@@ -305,6 +309,10 @@ static int cmp_first_kex_algo(const char *client_str,
 
     int is_wrong = 1;
 
+    if (client_str == NULL || server_str == NULL) {
+        return is_wrong;
+    }
+
     colon = strchr(client_str, ',');
     if (colon == NULL) {
         client_kex_len = strlen(client_str);
@@ -331,6 +339,7 @@ static int cmp_first_kex_algo(const char *client_str,
 SSH_PACKET_CALLBACK(ssh_packet_kexinit)
 {
     int i, ok;
+    struct ssh_crypto_struct *crypto = session->next_crypto;
     int server_kex = session->server;
     ssh_string str = NULL;
     char *strings[SSH_KEX_METHODS] = {0};
@@ -344,35 +353,67 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
     (void)type;
     (void)user;
 
+    SSH_LOG(SSH_LOG_TRACE, "KEXINIT received");
+
     if (session->session_state == SSH_SESSION_STATE_AUTHENTICATED) {
-        SSH_LOG(SSH_LOG_INFO, "Initiating key re-exchange");
+        if (session->dh_handshake_state == DH_STATE_FINISHED) {
+            SSH_LOG(SSH_LOG_DEBUG, "Peer initiated key re-exchange");
+            /* Reset the sent flag if the re-kex was initiated by the peer */
+            session->flags &= ~SSH_SESSION_FLAG_KEXINIT_SENT;
+        } else if (session->flags & SSH_SESSION_FLAG_KEXINIT_SENT &&
+                   session->dh_handshake_state == DH_STATE_INIT_SENT) {
+            /* This happens only when we are sending our-guessed first kex
+             * packet right after our KEXINIT packet. */
+            SSH_LOG(SSH_LOG_DEBUG, "Received peer kexinit answer.");
+        } else if (session->session_state != SSH_SESSION_STATE_INITIAL_KEX) {
+            ssh_set_error(session, SSH_FATAL,
+                          "SSH_KEXINIT received in wrong state");
+            goto error;
+        }
     } else if (session->session_state != SSH_SESSION_STATE_INITIAL_KEX) {
-        ssh_set_error(session,SSH_FATAL,"SSH_KEXINIT received in wrong state");
+        ssh_set_error(session, SSH_FATAL,
+                      "SSH_KEXINIT received in wrong state");
         goto error;
     }
 
     if (server_kex) {
-        len = ssh_buffer_get_data(packet,session->next_crypto->client_kex.cookie, 16);
+#ifdef WITH_SERVER
+        len = ssh_buffer_get_data(packet, crypto->client_kex.cookie, 16);
         if (len != 16) {
-            ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
+            ssh_set_error(session, SSH_FATAL,
+                          "ssh_packet_kexinit: no cookie in packet");
             goto error;
         }
 
-        ok = ssh_hashbufin_add_cookie(session, session->next_crypto->client_kex.cookie);
+        ok = ssh_hashbufin_add_cookie(session, crypto->client_kex.cookie);
         if (ok < 0) {
-            ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
+            ssh_set_error(session, SSH_FATAL,
+                          "ssh_packet_kexinit: adding cookie failed");
             goto error;
         }
+
+        ok = server_set_kex(session);
+        if (ok == SSH_ERROR) {
+            goto error;
+        }
+#endif
     } else {
-        len = ssh_buffer_get_data(packet,session->next_crypto->server_kex.cookie, 16);
+        len = ssh_buffer_get_data(packet, crypto->server_kex.cookie, 16);
         if (len != 16) {
-            ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: no cookie in packet");
+            ssh_set_error(session, SSH_FATAL,
+                          "ssh_packet_kexinit: no cookie in packet");
             goto error;
         }
 
-        ok = ssh_hashbufin_add_cookie(session, session->next_crypto->server_kex.cookie);
+        ok = ssh_hashbufin_add_cookie(session, crypto->server_kex.cookie);
         if (ok < 0) {
-            ssh_set_error(session, SSH_FATAL, "ssh_packet_kexinit: adding cookie failed");
+            ssh_set_error(session, SSH_FATAL,
+                          "ssh_packet_kexinit: adding cookie failed");
+            goto error;
+        }
+
+        ok = ssh_set_client_kex(session);
+        if (ok == SSH_ERROR) {
             goto error;
         }
     }
@@ -385,7 +426,8 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
 
         rc = ssh_buffer_add_ssh_string(session->in_hashbuf, str);
         if (rc < 0) {
-            ssh_set_error(session, SSH_FATAL, "Error adding string in hash buffer");
+            ssh_set_error(session, SSH_FATAL,
+                          "Error adding string in hash buffer");
             goto error;
         }
 
@@ -398,14 +440,14 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
         str = NULL;
     }
 
-    /* copy the server kex info into an array of strings */
+    /* copy the peer kex info into an array of strings */
     if (server_kex) {
         for (i = 0; i < SSH_KEX_METHODS; i++) {
-            session->next_crypto->client_kex.methods[i] = strings[i];
+            crypto->client_kex.methods[i] = strings[i];
         }
     } else { /* client */
         for (i = 0; i < SSH_KEX_METHODS; i++) {
-            session->next_crypto->server_kex.methods[i] = strings[i];
+            crypto->server_kex.methods[i] = strings[i];
         }
     }
 
@@ -419,30 +461,69 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
      * that its value is included when computing the session ID (see
      * 'make_sessionid').
      */
+    rc = ssh_buffer_get_u8(packet, &first_kex_packet_follows);
+    if (rc != 1) {
+        goto error;
+    }
+
+    rc = ssh_buffer_add_u8(session->in_hashbuf, first_kex_packet_follows);
+    if (rc < 0) {
+        goto error;
+    }
+
+    rc = ssh_buffer_add_u32(session->in_hashbuf, kexinit_reserved);
+    if (rc < 0) {
+        goto error;
+    }
+
+    /*
+     * Remember whether 'first_kex_packet_follows' was set and the client
+     * guess was wrong: in this case the next SSH_MSG_KEXDH_INIT message
+     * must be ignored on the server side.
+     * Client needs to start the Key exchange over with the correct method
+     */
+    if (first_kex_packet_follows || session->send_first_kex_follows) {
+        char **client_methods = crypto->client_kex.methods;
+        char **server_methods = crypto->server_kex.methods;
+        session->first_kex_follows_guess_wrong =
+            cmp_first_kex_algo(client_methods[SSH_KEX],
+                               server_methods[SSH_KEX]) ||
+            cmp_first_kex_algo(client_methods[SSH_HOSTKEYS],
+                               server_methods[SSH_HOSTKEYS]);
+            SSH_LOG(SSH_LOG_DEBUG, "The initial guess was %s.",
+                    session->first_kex_follows_guess_wrong ? "wrong" : "right");
+    }
+
+    /*
+     * handle the "strict KEX" feature. If supported by peer, then set up the
+     * flag and verify packet sequence numbers.
+     */
     if (server_kex) {
-        rc = ssh_buffer_get_u8(packet, &first_kex_packet_follows);
-        if (rc != 1) {
-            goto error;
+        ok = ssh_match_group(crypto->client_kex.methods[SSH_KEX],
+                             KEX_STRICT_CLIENT);
+        if (ok) {
+            SSH_LOG(SSH_LOG_DEBUG, "Client supports strict kex, enabling.");
+            session->flags |= SSH_SESSION_FLAG_KEX_STRICT;
         }
-
-        rc = ssh_buffer_add_u8(session->in_hashbuf, first_kex_packet_follows);
-        if (rc < 0) {
-            goto error;
-        }
-
-        rc = ssh_buffer_add_u32(session->in_hashbuf, kexinit_reserved);
-        if (rc < 0) {
-            goto error;
+    } else {
+        /* client kex */
+        ok = ssh_match_group(crypto->server_kex.methods[SSH_KEX],
+                             KEX_STRICT_SERVER);
+        if (ok) {
+            SSH_LOG(SSH_LOG_DEBUG, "Server supports strict kex, enabling.");
+            session->flags |= SSH_SESSION_FLAG_KEX_STRICT;
         }
+    }
 
+    if (server_kex) {
         /*
          * If client sent a ext-info-c message in the kex list, it supports
          * RFC 8308 extension negotiation.
          */
-        ok = ssh_match_group(session->next_crypto->client_kex.methods[SSH_KEX],
+        ok = ssh_match_group(crypto->client_kex.methods[SSH_KEX],
                              KEX_EXTENSION_CLIENT);
         if (ok) {
-            const char *hostkeys = NULL;
+            const char *hostkeys = NULL, *wanted_hostkeys = NULL;
 
             /* The client supports extension negotiation */
             session->extensions |= SSH_EXT_NEGOTIATION;
@@ -452,14 +533,14 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
              * by the client and enable the respective extensions to provide
              * correct signature in the next packet if RSA is negotiated
              */
-            hostkeys = session->next_crypto->client_kex.methods[SSH_HOSTKEYS];
+            hostkeys = crypto->client_kex.methods[SSH_HOSTKEYS];
+            wanted_hostkeys = session->opts.wanted_methods[SSH_HOSTKEYS];
             ok = ssh_match_group(hostkeys, "rsa-sha2-512");
             if (ok) {
                 /* Check if rsa-sha2-512 is allowed by config */
-                if (session->opts.wanted_methods[SSH_HOSTKEYS] != NULL) {
-                    char *is_allowed =
-                        ssh_find_matching(session->opts.wanted_methods[SSH_HOSTKEYS],
-                                          "rsa-sha2-512");
+                if (wanted_hostkeys != NULL) {
+                    char *is_allowed = ssh_find_matching(wanted_hostkeys,
+                                                         "rsa-sha2-512");
                     if (is_allowed != NULL) {
                         session->extensions |= SSH_EXT_SIG_RSA_SHA512;
                     }
@@ -469,10 +550,9 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
             ok = ssh_match_group(hostkeys, "rsa-sha2-256");
             if (ok) {
                 /* Check if rsa-sha2-256 is allowed by config */
-                if (session->opts.wanted_methods[SSH_HOSTKEYS] != NULL) {
-                    char *is_allowed =
-                        ssh_find_matching(session->opts.wanted_methods[SSH_HOSTKEYS],
-                                          "rsa-sha2-256");
+                if (wanted_hostkeys != NULL) {
+                    char *is_allowed = ssh_find_matching(wanted_hostkeys,
+                                                         "rsa-sha2-256");
                     if (is_allowed != NULL) {
                         session->extensions |= SSH_EXT_SIG_RSA_SHA256;
                     }
@@ -488,7 +568,7 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
                 (session->extensions & SSH_EXT_SIG_RSA_SHA512)) {
                 session->extensions &= ~(SSH_EXT_SIG_RSA_SHA256 | SSH_EXT_SIG_RSA_SHA512);
                 rsa_sig_ext = ssh_find_matching("rsa-sha2-512,rsa-sha2-256",
-                                                session->next_crypto->client_kex.methods[SSH_HOSTKEYS]);
+                                                hostkeys);
                 if (rsa_sig_ext == NULL) {
                     goto error; /* should never happen */
                 } else if (strcmp(rsa_sig_ext, "rsa-sha2-512") == 0) {
@@ -507,24 +587,16 @@ SSH_PACKET_CALLBACK(ssh_packet_kexinit)
                     session->extensions & SSH_EXT_SIG_RSA_SHA256 ? "SHA256" : "",
                     session->extensions & SSH_EXT_SIG_RSA_SHA512 ? " SHA512" : "");
         }
-
-        /*
-         * Remember whether 'first_kex_packet_follows' was set and the client
-         * guess was wrong: in this case the next SSH_MSG_KEXDH_INIT message
-         * must be ignored.
-         */
-        if (first_kex_packet_follows) {
-          session->first_kex_follows_guess_wrong =
-            cmp_first_kex_algo(session->next_crypto->client_kex.methods[SSH_KEX],
-                               session->next_crypto->server_kex.methods[SSH_KEX]) ||
-            cmp_first_kex_algo(session->next_crypto->client_kex.methods[SSH_HOSTKEYS],
-                               session->next_crypto->server_kex.methods[SSH_HOSTKEYS]);
-        }
     }
 
     /* Note, that his overwrites authenticated state in case of rekeying */
     session->session_state = SSH_SESSION_STATE_KEXINIT_RECEIVED;
-    session->dh_handshake_state = DH_STATE_INIT;
+    /* if we already sent our initial key exchange packet, do not reset the
+     * DH state. We will know if we were right with our guess only in
+     * dh_handshake_state() */
+    if (session->send_first_kex_follows == false) {
+        session->dh_handshake_state = DH_STATE_INIT;
+    }
     session->ssh_connection_callback(session);
     return SSH_PACKET_USED;
 
@@ -666,11 +738,14 @@ int ssh_set_client_kex(ssh_session session)
 {
     struct ssh_kex_struct *client = &session->next_crypto->client_kex;
     const char *wanted;
-    char *kex = NULL;
-    char *kex_tmp = NULL;
     int ok;
     int i;
-    size_t kex_len, len;
+
+    /* Skip if already set, for example for the rekey or when we do the guessing
+     * it could have been already used to make some protocol decisions. */
+    if (client->methods[0] != NULL) {
+        return SSH_OK;
+    }
 
     ok = ssh_get_random(client->cookie, 16, 0);
     if (!ok) {
@@ -678,8 +753,6 @@ int ssh_set_client_kex(ssh_session session)
         return SSH_ERROR;
     }
 
-    memset(client->methods, 0, SSH_KEX_METHODS * sizeof(char **));
-
     /* Set the list of allowed algorithms in order of preference, if it hadn't
      * been set yet. */
     for (i = 0; i < SSH_KEX_METHODS; i++) {
@@ -715,23 +788,52 @@ int ssh_set_client_kex(ssh_session session)
         return SSH_OK;
     }
 
-    /* Here we append  ext-info-c  to the list of kex algorithms */
-    kex = client->methods[SSH_KEX];
+    ok = ssh_kex_append_extensions(session, client);
+    if (ok != SSH_OK){
+        return ok;
+    }
+
+    return SSH_OK;
+}
+
+int ssh_kex_append_extensions(ssh_session session, struct ssh_kex_struct *pkex)
+{
+    char *kex = NULL;
+    char *kex_tmp = NULL;
+    size_t kex_len, len;
+
+    /* Here we append ext-info-c and kex-strict-c-v00@openssh.com for client
+     * and kex-strict-s-v00@openssh.com for server to the list of kex algorithms
+     */
+    kex = pkex->methods[SSH_KEX];
     len = strlen(kex);
-    if (len + strlen(KEX_EXTENSION_CLIENT) + 2 < len) {
+    if (session->server) {
+        /* Comma, nul byte */
+        kex_len = len + 1 + strlen(KEX_STRICT_SERVER) + 1;
+    } else {
+        /* Comma, comma, nul byte */
+        kex_len = len + 1 + strlen(KEX_EXTENSION_CLIENT) + 1 +
+                  strlen(KEX_STRICT_CLIENT) + 1;
+    }
+    if (kex_len >= MAX_PACKET_LEN) {
         /* Overflow */
         return SSH_ERROR;
     }
-    kex_len = len + strlen(KEX_EXTENSION_CLIENT) + 2; /* comma, NULL */
     kex_tmp = realloc(kex, kex_len);
     if (kex_tmp == NULL) {
-        free(kex);
         ssh_set_error_oom(session);
         return SSH_ERROR;
     }
-    snprintf(kex_tmp + len, kex_len - len, ",%s", KEX_EXTENSION_CLIENT);
-    client->methods[SSH_KEX] = kex_tmp;
-
+    if (session->server){
+        snprintf(kex_tmp + len, kex_len - len, ",%s", KEX_STRICT_SERVER);
+    } else {
+        snprintf(kex_tmp + len,
+                 kex_len - len,
+                 ",%s,%s",
+                 KEX_EXTENSION_CLIENT,
+                 KEX_STRICT_CLIENT);
+    }
+    pkex->methods[SSH_KEX] = kex_tmp;
     return SSH_OK;
 }
 
@@ -749,70 +851,141 @@ static const char *ssh_find_aead_hmac(const char *cipher)
     return NULL;
 }
 
+static enum ssh_key_exchange_e
+kex_select_kex_type(const char *kex)
+{
+    if (strcmp(kex, "diffie-hellman-group1-sha1") == 0) {
+        return SSH_KEX_DH_GROUP1_SHA1;
+    } else if (strcmp(kex, "diffie-hellman-group14-sha1") == 0) {
+        return SSH_KEX_DH_GROUP14_SHA1;
+    } else if (strcmp(kex, "diffie-hellman-group14-sha256") == 0) {
+        return SSH_KEX_DH_GROUP14_SHA256;
+    } else if (strcmp(kex, "diffie-hellman-group16-sha512") == 0) {
+        return SSH_KEX_DH_GROUP16_SHA512;
+    } else if (strcmp(kex, "diffie-hellman-group18-sha512") == 0) {
+        return SSH_KEX_DH_GROUP18_SHA512;
+#ifdef WITH_GEX
+    } else if (strcmp(kex, "diffie-hellman-group-exchange-sha1") == 0) {
+        return SSH_KEX_DH_GEX_SHA1;
+    } else if (strcmp(kex, "diffie-hellman-group-exchange-sha256") == 0) {
+        return SSH_KEX_DH_GEX_SHA256;
+#endif /* WITH_GEX */
+    } else if (strcmp(kex, "ecdh-sha2-nistp256") == 0) {
+        return SSH_KEX_ECDH_SHA2_NISTP256;
+    } else if (strcmp(kex, "ecdh-sha2-nistp384") == 0) {
+        return SSH_KEX_ECDH_SHA2_NISTP384;
+    } else if (strcmp(kex, "ecdh-sha2-nistp521") == 0) {
+        return SSH_KEX_ECDH_SHA2_NISTP521;
+    } else if (strcmp(kex, "curve25519-sha256@libssh.org") == 0) {
+        return SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG;
+    } else if (strcmp(kex, "curve25519-sha256") == 0) {
+        return SSH_KEX_CURVE25519_SHA256;
+    }
+    /* should not happen. We should be getting only valid names at this stage */
+    return 0;
+}
+
+
+/** @internal
+ * @brief Reverts guessed callbacks set during the dh_handshake()
+ * @param session session handle
+ * @returns void
+ */
+static void revert_kex_callbacks(ssh_session session)
+{
+    switch (session->next_crypto->kex_type) {
+    case SSH_KEX_DH_GROUP1_SHA1:
+    case SSH_KEX_DH_GROUP14_SHA1:
+    case SSH_KEX_DH_GROUP14_SHA256:
+    case SSH_KEX_DH_GROUP16_SHA512:
+    case SSH_KEX_DH_GROUP18_SHA512:
+        ssh_client_dh_remove_callbacks(session);
+        break;
+#ifdef WITH_GEX
+    case SSH_KEX_DH_GEX_SHA1:
+    case SSH_KEX_DH_GEX_SHA256:
+        ssh_client_dhgex_remove_callbacks(session);
+        break;
+#endif /* WITH_GEX */
+#ifdef HAVE_ECDH
+    case SSH_KEX_ECDH_SHA2_NISTP256:
+    case SSH_KEX_ECDH_SHA2_NISTP384:
+    case SSH_KEX_ECDH_SHA2_NISTP521:
+        ssh_client_ecdh_remove_callbacks(session);
+        break;
+#endif
+#ifdef HAVE_CURVE25519
+    case SSH_KEX_CURVE25519_SHA256:
+    case SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG:
+        ssh_client_curve25519_remove_callbacks(session);
+        break;
+#endif
+    }
+}
+
 /** @brief Select the different methods on basis of client's and
  * server's kex messages, and watches out if a match is possible.
  */
 int ssh_kex_select_methods (ssh_session session)
 {
-    struct ssh_kex_struct *server = &session->next_crypto->server_kex;
-    struct ssh_kex_struct *client = &session->next_crypto->client_kex;
+    struct ssh_crypto_struct *crypto = session->next_crypto;
+    struct ssh_kex_struct *server = &crypto->server_kex;
+    struct ssh_kex_struct *client = &crypto->client_kex;
     char *ext_start = NULL;
     const char *aead_hmac = NULL;
+    enum ssh_key_exchange_e kex_type;
     int i;
 
-    /* Here we should drop the  ext-info-c  from the list so we avoid matching.
+    /* Here we should drop the extensions from the list so we avoid matching.
      * it. We added it to the end, so we can just truncate the string here */
-    ext_start = strstr(client->methods[SSH_KEX], ","KEX_EXTENSION_CLIENT);
-    if (ext_start != NULL) {
-        ext_start[0] = '\0';
+    if (session->client) {
+        ext_start = strstr(client->methods[SSH_KEX], "," KEX_EXTENSION_CLIENT);
+        if (ext_start != NULL) {
+            ext_start[0] = '\0';
+        }
+    }
+    if (session->server) {
+        ext_start = strstr(server->methods[SSH_KEX], "," KEX_STRICT_SERVER);
+        if (ext_start != NULL) {
+            ext_start[0] = '\0';
+        }
     }
 
     for (i = 0; i < SSH_KEX_METHODS; i++) {
-        session->next_crypto->kex_methods[i]=ssh_find_matching(server->methods[i],client->methods[i]);
+        crypto->kex_methods[i] = ssh_find_matching(server->methods[i],
+                                                   client->methods[i]);
 
         if (i == SSH_MAC_C_S || i == SSH_MAC_S_C) {
-            aead_hmac = ssh_find_aead_hmac(session->next_crypto->kex_methods[i-2]);
+            aead_hmac = ssh_find_aead_hmac(crypto->kex_methods[i - 2]);
             if (aead_hmac) {
-                free(session->next_crypto->kex_methods[i]);
-                session->next_crypto->kex_methods[i] = strdup(aead_hmac);
+                free(crypto->kex_methods[i]);
+                crypto->kex_methods[i] = strdup(aead_hmac);
             }
         }
-        if (session->next_crypto->kex_methods[i] == NULL && i < SSH_LANG_C_S){
-            ssh_set_error(session,SSH_FATAL,"kex error : no match for method %s: server [%s], client [%s]",
-                    ssh_kex_descriptions[i],server->methods[i],client->methods[i]);
+        if (crypto->kex_methods[i] == NULL && i < SSH_LANG_C_S) {
+            ssh_set_error(session, SSH_FATAL,
+                          "kex error : no match for method %s: server [%s], "
+                          "client [%s]", ssh_kex_descriptions[i],
+                          server->methods[i], client->methods[i]);
             return SSH_ERROR;
-        } else if ((i >= SSH_LANG_C_S) && (session->next_crypto->kex_methods[i] == NULL)) {
+        } else if ((i >= SSH_LANG_C_S) && (crypto->kex_methods[i] == NULL)) {
             /* we can safely do that for languages */
-            session->next_crypto->kex_methods[i] = strdup("");
+            crypto->kex_methods[i] = strdup("");
         }
     }
-    if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group1-sha1") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GROUP1_SHA1;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group14-sha1") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GROUP14_SHA1;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group14-sha256") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GROUP14_SHA256;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group16-sha512") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GROUP16_SHA512;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group18-sha512") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GROUP18_SHA512;
-#ifdef WITH_GEX
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group-exchange-sha1") == 0){
-      session->next_crypto->kex_type=SSH_KEX_DH_GEX_SHA1;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "diffie-hellman-group-exchange-sha256") == 0){
-        session->next_crypto->kex_type=SSH_KEX_DH_GEX_SHA256;
-#endif /* WITH_GEX */
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "ecdh-sha2-nistp256") == 0){
-      session->next_crypto->kex_type=SSH_KEX_ECDH_SHA2_NISTP256;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "ecdh-sha2-nistp384") == 0){
-      session->next_crypto->kex_type=SSH_KEX_ECDH_SHA2_NISTP384;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "ecdh-sha2-nistp521") == 0){
-      session->next_crypto->kex_type=SSH_KEX_ECDH_SHA2_NISTP521;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "curve25519-sha256@libssh.org") == 0){
-      session->next_crypto->kex_type=SSH_KEX_CURVE25519_SHA256_LIBSSH_ORG;
-    } else if (strcmp(session->next_crypto->kex_methods[SSH_KEX], "curve25519-sha256") == 0){
-      session->next_crypto->kex_type=SSH_KEX_CURVE25519_SHA256;
+
+    /* We can not set this value directly as the old value is needed to revert
+     * callbacks if we are client */
+    kex_type = kex_select_kex_type(crypto->kex_methods[SSH_KEX]);
+    if (session->client && session->first_kex_follows_guess_wrong) {
+        SSH_LOG(SSH_LOG_DEBUG, "Our guess was wrong. Restarting the KEX");
+        /* We need to remove the wrong callbacks and start kex again */
+        revert_kex_callbacks(session);
+        session->dh_handshake_state = DH_STATE_INIT;
+        session->first_kex_follows_guess_wrong = false;
     }
+    crypto->kex_type = kex_type;
+
     SSH_LOG(SSH_LOG_INFO, "Negotiated %s,%s,%s,%s,%s,%s,%s,%s,%s,%s",
             session->next_crypto->kex_methods[SSH_KEX],
             session->next_crypto->kex_methods[SSH_HOSTKEYS],
@@ -830,63 +1003,116 @@ int ssh_kex_select_methods (ssh_session session)
 
 
 /* this function only sends the predefined set of kex methods */
-int ssh_send_kex(ssh_session session, int server_kex)
+int ssh_send_kex(ssh_session session)
 {
-  struct ssh_kex_struct *kex = (server_kex ? &session->next_crypto->server_kex :
-      &session->next_crypto->client_kex);
-  ssh_string str = NULL;
-  int i;
-  int rc;
+    struct ssh_kex_struct *kex = (session->server ?
+        &session->next_crypto->server_kex :
+        &session->next_crypto->client_kex);
+    ssh_string str = NULL;
+    int i;
+    int rc;
+    int first_kex_packet_follows = 0;
 
-  rc = ssh_buffer_pack(session->out_buffer,
-                       "bP",
-                       SSH2_MSG_KEXINIT,
-                       16,
-                       kex->cookie); /* cookie */
-  if (rc != SSH_OK)
-    goto error;
-  if (ssh_hashbufout_add_cookie(session) < 0) {
-    goto error;
-  }
-
-  ssh_list_kex(kex);
-
-  for (i = 0; i < SSH_KEX_METHODS; i++) {
-    str = ssh_string_from_char(kex->methods[i]);
-    if (str == NULL) {
-      goto error;
+    /* Only client can initiate the handshake methods we implement. If we
+     * already received the peer mechanisms, there is no point in guessing */
+    if (session->client &&
+        session->session_state != SSH_SESSION_STATE_KEXINIT_RECEIVED &&
+        session->send_first_kex_follows) {
+        first_kex_packet_follows = 1;
     }
 
-    if (ssh_buffer_add_ssh_string(session->out_hashbuf, str) < 0) {
-      goto error;
+    SSH_LOG(SSH_LOG_TRACE,
+            "Sending KEXINIT packet, first_kex_packet_follows = %d",
+            first_kex_packet_follows);
+
+    rc = ssh_buffer_pack(session->out_buffer,
+                         "bP",
+                         SSH2_MSG_KEXINIT,
+                         16,
+                         kex->cookie); /* cookie */
+    if (rc != SSH_OK)
+        goto error;
+    if (ssh_hashbufout_add_cookie(session) < 0) {
+        goto error;
     }
-    if (ssh_buffer_add_ssh_string(session->out_buffer, str) < 0) {
-      goto error;
+
+    ssh_list_kex(kex);
+
+    for (i = 0; i < SSH_KEX_METHODS; i++) {
+        str = ssh_string_from_char(kex->methods[i]);
+        if (str == NULL) {
+            goto error;
+        }
+
+        rc = ssh_buffer_add_ssh_string(session->out_hashbuf, str);
+        if (rc < 0) {
+            goto error;
+        }
+        rc = ssh_buffer_add_ssh_string(session->out_buffer, str);
+        if (rc < 0) {
+            goto error;
+        }
+        SSH_STRING_FREE(str);
+        str = NULL;
     }
-    SSH_STRING_FREE(str);
-    str = NULL;
-  }
 
-  rc = ssh_buffer_pack(session->out_buffer,
-                       "bd",
-                       0,
-                       0);
-  if (rc != SSH_OK) {
-    goto error;
-  }
+    rc = ssh_buffer_pack(session->out_buffer,
+                         "bd",
+                         first_kex_packet_follows,
+                         0);
+    if (rc != SSH_OK) {
+        goto error;
+    }
 
-  if (ssh_packet_send(session) == SSH_ERROR) {
-    return -1;
-  }
+    /* Prepare also the first_kex_packet_follows and reserved to 0 */
+    rc = ssh_buffer_add_u8(session->out_hashbuf, first_kex_packet_follows);
+    if (rc < 0) {
+        goto error;
+    }
+    rc = ssh_buffer_add_u32(session->out_hashbuf, 0);
+    if (rc < 0) {
+        goto error;
+    }
+
+    rc = ssh_packet_send(session);
+    if (rc == SSH_ERROR) {
+        return -1;
+    }
+
+    session->flags |= SSH_SESSION_FLAG_KEXINIT_SENT;
+    SSH_LOG(SSH_LOG_PACKET, "SSH_MSG_KEXINIT sent");
+
+    /* If we indicated that we are sending the guessed key exchange packet,
+     * do it now. The packet is simple, but we need to do some preparations */
+    if (first_kex_packet_follows) {
+        char *list = kex->methods[SSH_KEX];
+        char *colon = strchr(list, ',');
+        size_t kex_name_len = colon ? (size_t)(colon - list) : strlen(list);
+        char *kex_name = calloc(kex_name_len + 1, 1);
+        if (kex_name == NULL) {
+            ssh_set_error_oom(session);
+            goto error;
+        }
+        snprintf(kex_name, kex_name_len + 1, "%.*s", (int)kex_name_len, list);
+        SSH_LOG(SSH_LOG_TRACE, "Sending the first kex packet for %s", kex_name);
+
+        session->next_crypto->kex_type = kex_select_kex_type(kex_name);
+        free(kex_name);
+
+        /* run the first step of the DH handshake */
+        session->dh_handshake_state = DH_STATE_INIT;
+        if (dh_handshake(session) == SSH_ERROR) {
+            goto error;
+        }
+    }
+    return 0;
 
-  SSH_LOG(SSH_LOG_PACKET, "SSH_MSG_KEXINIT sent");
-  return 0;
 error:
-  ssh_buffer_reinit(session->out_buffer);
-  ssh_buffer_reinit(session->out_hashbuf);
-  SSH_STRING_FREE(str);
+    ssh_buffer_reinit(session->out_buffer);
+    ssh_buffer_reinit(session->out_hashbuf);
+    SSH_STRING_FREE(str);
 
-  return -1;
+    return -1;
 }
 
 /*
@@ -929,7 +1155,7 @@ int ssh_send_rekex(ssh_session session)
     }
 
     session->dh_handshake_state = DH_STATE_INIT;
-    rc = ssh_send_kex(session, session->server);
+    rc = ssh_send_kex(session);
     if (rc < 0) {
         SSH_LOG(SSH_LOG_PACKET, "Failed to send kex");
         return rc;
@@ -1006,33 +1232,6 @@ int ssh_make_sessionid(ssh_session session)
         client_hash = session->in_hashbuf;
     }
 
-    /*
-     * Handle the two final fields for the KEXINIT message (RFC 4253 7.1):
-     *
-     *      boolean      first_kex_packet_follows
-     *      uint32       0 (reserved for future extension)
-     */
-    rc = ssh_buffer_add_u8(server_hash, 0);
-    if (rc < 0) {
-        goto error;
-    }
-    rc = ssh_buffer_add_u32(server_hash, 0);
-    if (rc < 0) {
-        goto error;
-    }
-
-    /* These fields are handled for the server case in ssh_packet_kexinit. */
-    if (session->client) {
-        rc = ssh_buffer_add_u8(client_hash, 0);
-        if (rc < 0) {
-            goto error;
-        }
-        rc = ssh_buffer_add_u32(client_hash, 0);
-        if (rc < 0) {
-            goto error;
-        }
-    }
-
     rc = ssh_dh_get_next_server_publickey_blob(session, &server_pubkey_blob);
     if (rc != SSH_OK) {
         goto error;

src/libcrypto.c

@@ -126,82 +126,48 @@ SHACTX sha1_init(void)
     return c;
 }
 
-void sha1_update(SHACTX c, const void *data, unsigned long len)
+void sha1_ctx_free(SHACTX c)
 {
-    EVP_DigestUpdate(c, data, len);
-}
-
-void sha1_final(unsigned char *md, SHACTX c)
-{
-    unsigned int mdlen = 0;
-
-    EVP_DigestFinal(c, md, &mdlen);
     EVP_MD_CTX_destroy(c);
 }
 
-void sha1(const unsigned char *digest, int len, unsigned char *hash)
+int sha1_update(SHACTX c, const void *data, unsigned long len)
+{
+    int rc = EVP_DigestUpdate(c, data, len);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha1_final(unsigned char *md, SHACTX c)
+{
+    unsigned int mdlen = 0;
+    int rc = EVP_DigestFinal(c, md, &mdlen);
+
+    EVP_MD_CTX_destroy(c);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha1(const unsigned char *digest, int len, unsigned char *hash)
 {
     SHACTX c = sha1_init();
-    if (c != NULL) {
-        sha1_update(c, digest, len);
-        sha1_final(hash, c);
+    int rc;
+
+    if (c == NULL) {
+        return SSH_ERROR;
     }
-}
-
-#ifdef HAVE_OPENSSL_ECC
-static const EVP_MD *nid_to_evpmd(int nid)
-{
-    switch (nid) {
-        case NID_X9_62_prime256v1:
-            return EVP_sha256();
-        case NID_secp384r1:
-            return EVP_sha384();
-        case NID_secp521r1:
-            return EVP_sha512();
-        default:
-            return NULL;
+    rc = sha1_update(c, digest, len);
+    if (rc != SSH_OK) {
+        sha1_ctx_free(c);
+        return SSH_ERROR;
     }
-
-    return NULL;
+    return  sha1_final(hash, c);
 }
 
-void evp(int nid, unsigned char *digest, int len, unsigned char *hash, unsigned int *hlen)
-{
-    const EVP_MD *evp_md = nid_to_evpmd(nid);
-    EVP_MD_CTX *md = EVP_MD_CTX_new();
-
-    EVP_DigestInit(md, evp_md);
-    EVP_DigestUpdate(md, digest, len);
-    EVP_DigestFinal(md, hash, hlen);
-    EVP_MD_CTX_free(md);
-}
-
-EVPCTX evp_init(int nid)
-{
-    const EVP_MD *evp_md = nid_to_evpmd(nid);
-
-    EVPCTX ctx = EVP_MD_CTX_new();
-    if (ctx == NULL) {
-        return NULL;
-    }
-
-    EVP_DigestInit(ctx, evp_md);
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, unsigned long len)
-{
-    EVP_DigestUpdate(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    EVP_DigestFinal(ctx, md, mdlen);
-    EVP_MD_CTX_free(ctx);
-}
-#endif
-
 SHA256CTX sha256_init(void)
 {
     int rc;
@@ -218,26 +184,46 @@ SHA256CTX sha256_init(void)
     return c;
 }
 
-void sha256_update(SHA256CTX c, const void *data, unsigned long len)
+void sha256_ctx_free(SHA256CTX c)
 {
-    EVP_DigestUpdate(c, data, len);
-}
-
-void sha256_final(unsigned char *md, SHA256CTX c)
-{
-    unsigned int mdlen = 0;
-
-    EVP_DigestFinal(c, md, &mdlen);
     EVP_MD_CTX_destroy(c);
 }
 
-void sha256(const unsigned char *digest, int len, unsigned char *hash)
+int sha256_update(SHA256CTX c, const void *data, unsigned long len)
+{
+    int rc = EVP_DigestUpdate(c, data, len);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha256_final(unsigned char *md, SHA256CTX c)
+{
+    unsigned int mdlen = 0;
+    int rc = EVP_DigestFinal(c, md, &mdlen);
+
+    EVP_MD_CTX_destroy(c);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha256(const unsigned char *digest, int len, unsigned char *hash)
 {
     SHA256CTX c = sha256_init();
-    if (c != NULL) {
-        sha256_update(c, digest, len);
-        sha256_final(hash, c);
+    int rc;
+
+    if (c == NULL) {
+        return SSH_ERROR;
     }
+    rc = sha256_update(c, digest, len);
+    if (rc != SSH_OK) {
+        sha256_ctx_free(c);
+        return SSH_ERROR;
+    }
+    return sha256_final(hash, c);
 }
 
 SHA384CTX sha384_init(void)
@@ -256,26 +242,47 @@ SHA384CTX sha384_init(void)
     return c;
 }
 
-void sha384_update(SHA384CTX c, const void *data, unsigned long len)
+void
+sha384_ctx_free(SHA384CTX c)
 {
-    EVP_DigestUpdate(c, data, len);
-}
-
-void sha384_final(unsigned char *md, SHA384CTX c)
-{
-    unsigned int mdlen = 0;
-
-    EVP_DigestFinal(c, md, &mdlen);
     EVP_MD_CTX_destroy(c);
 }
 
-void sha384(const unsigned char *digest, int len, unsigned char *hash)
+int sha384_update(SHA384CTX c, const void *data, unsigned long len)
+{
+    int rc = EVP_DigestUpdate(c, data, len);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha384_final(unsigned char *md, SHA384CTX c)
+{
+    unsigned int mdlen = 0;
+    int rc = EVP_DigestFinal(c, md, &mdlen);
+
+    EVP_MD_CTX_destroy(c);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha384(const unsigned char *digest, int len, unsigned char *hash)
 {
     SHA384CTX c = sha384_init();
-    if (c != NULL) {
-        sha384_update(c, digest, len);
-        sha384_final(hash, c);
+    int rc;
+
+    if (c == NULL) {
+        return SSH_ERROR;
     }
+    rc = sha384_update(c, digest, len);
+    if (rc != SSH_OK) {
+        sha384_ctx_free(c);
+        return SSH_ERROR;
+    }
+    return sha384_final(hash, c);
 }
 
 SHA512CTX sha512_init(void)
@@ -294,26 +301,46 @@ SHA512CTX sha512_init(void)
     return c;
 }
 
-void sha512_update(SHA512CTX c, const void *data, unsigned long len)
+void sha512_ctx_free(SHA512CTX c)
 {
-    EVP_DigestUpdate(c, data, len);
-}
-
-void sha512_final(unsigned char *md, SHA512CTX c)
-{
-    unsigned int mdlen = 0;
-
-    EVP_DigestFinal(c, md, &mdlen);
     EVP_MD_CTX_destroy(c);
 }
 
-void sha512(const unsigned char *digest, int len, unsigned char *hash)
+int sha512_update(SHA512CTX c, const void *data, unsigned long len)
+{
+    int rc = EVP_DigestUpdate(c, data, len);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha512_final(unsigned char *md, SHA512CTX c)
+{
+    unsigned int mdlen = 0;
+    int rc = EVP_DigestFinal(c, md, &mdlen);
+
+    EVP_MD_CTX_destroy(c);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha512(const unsigned char *digest, int len, unsigned char *hash)
 {
     SHA512CTX c = sha512_init();
-    if (c != NULL) {
-        sha512_update(c, digest, len);
-        sha512_final(hash, c);
+    int rc;
+
+    if (c == NULL) {
+        return SSH_ERROR;
     }
+    rc = sha512_update(c, digest, len);
+    if (rc != SSH_OK) {
+        sha512_ctx_free(c);
+        return SSH_ERROR;
+    }
+    return sha512_final(hash, c);
 }
 
 MD5CTX md5_init(void)
@@ -332,19 +359,33 @@ MD5CTX md5_init(void)
     return c;
 }
 
-void md5_update(MD5CTX c, const void *data, unsigned long len)
+void md5_ctx_free(MD5CTX c)
 {
-    EVP_DigestUpdate(c, data, len);
-}
-
-void md5_final(unsigned char *md, MD5CTX c)
-{
-    unsigned int mdlen = 0;
-
-    EVP_DigestFinal(c, md, &mdlen);
     EVP_MD_CTX_destroy(c);
 }
 
+int md5_update(MD5CTX c, const void *data, unsigned long len)
+{
+    int rc = EVP_DigestUpdate(c, data, len);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int md5_final(unsigned char *md, MD5CTX c)
+{
+    unsigned int mdlen = 0;
+    int rc = EVP_DigestFinal(c, md, &mdlen);
+
+    EVP_MD_CTX_destroy(c);
+    if (rc != 1) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+
 #ifdef HAVE_OPENSSL_EVP_KDF_CTX_NEW_ID
 static const EVP_MD *sshkdf_digest_to_md(enum ssh_kdf_digest digest_type)
 {

src/libgcrypt.c

@@ -68,72 +68,37 @@ SHACTX sha1_init(void) {
   return ctx;
 }
 
-void sha1_update(SHACTX c, const void *data, unsigned long len) {
+void
+sha1_ctx_free(SHACTX c)
+{
+    gcry_md_close(c);
+}
+
+int sha1_update(SHACTX c, const void *data, unsigned long len) {
   gcry_md_write(c, data, len);
+  return SSH_OK;
 }
 
-void sha1_final(unsigned char *md, SHACTX c) {
-  gcry_md_final(c);
-  memcpy(md, gcry_md_read(c, 0), SHA_DIGEST_LEN);
-  gcry_md_close(c);
+int sha1_final(unsigned char *md, SHACTX c)
+{
+    unsigned char *tmp = NULL;
+
+    gcry_md_final(c);
+    tmp = gcry_md_read(c, 0);
+    if (tmp == NULL) {
+        gcry_md_close(c);
+        return SSH_ERROR;
+    }
+    memcpy(md, tmp, SHA_DIGEST_LEN);
+    gcry_md_close(c);
+    return SSH_OK;
 }
 
-void sha1(const unsigned char *digest, int len, unsigned char *hash) {
+int sha1(const unsigned char *digest, int len, unsigned char *hash) {
   gcry_md_hash_buffer(GCRY_MD_SHA1, hash, digest, len);
+  return SSH_OK;
 }
 
-#ifdef HAVE_GCRYPT_ECC
-static int nid_to_md_algo(int nid)
-{
-    switch (nid) {
-    case NID_gcrypt_nistp256:
-        return GCRY_MD_SHA256;
-    case NID_gcrypt_nistp384:
-        return GCRY_MD_SHA384;
-    case NID_gcrypt_nistp521:
-        return GCRY_MD_SHA512;
-    }
-    return GCRY_MD_NONE;
-}
-
-void evp(int nid, unsigned char *digest, int len,
-         unsigned char *hash, unsigned int *hlen)
-{
-    int algo = nid_to_md_algo(nid);
-
-    /* Note: What gcrypt calls 'hash' is called 'digest' here and
-       vice-versa.  */
-    gcry_md_hash_buffer(algo, hash, digest, len);
-    *hlen = gcry_md_get_algo_dlen(algo);
-}
-
-EVPCTX evp_init(int nid)
-{
-    gcry_error_t err;
-    int algo = nid_to_md_algo(nid);
-    EVPCTX ctx;
-
-    err = gcry_md_open(&ctx, algo, 0);
-    if (err) {
-        return NULL;
-    }
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, unsigned long len)
-{
-    gcry_md_write(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    int algo = gcry_md_get_algo(ctx);
-    *mdlen = gcry_md_get_algo_dlen(algo);
-    memcpy(md, gcry_md_read(ctx, algo), *mdlen);
-    gcry_md_close(ctx);
-}
-#endif
 
 SHA256CTX sha256_init(void) {
   SHA256CTX ctx = NULL;
@@ -142,18 +107,35 @@ SHA256CTX sha256_init(void) {
   return ctx;
 }
 
-void sha256_update(SHACTX c, const void *data, unsigned long len) {
+void
+sha256_ctx_free(SHA256CTX c)
+{
+    gcry_md_close(c);
+}
+
+int sha256_update(SHACTX c, const void *data, unsigned long len) {
   gcry_md_write(c, data, len);
+  return SSH_OK;
 }
 
-void sha256_final(unsigned char *md, SHACTX c) {
-  gcry_md_final(c);
-  memcpy(md, gcry_md_read(c, 0), SHA256_DIGEST_LEN);
-  gcry_md_close(c);
+int sha256_final(unsigned char *md, SHACTX c)
+{
+    unsigned char *tmp = NULL;
+
+    gcry_md_final(c);
+    tmp = gcry_md_read(c, 0);
+    if (tmp == NULL) {
+        gcry_md_close(c);
+        return SSH_ERROR;
+    }
+    memcpy(md, tmp, SHA256_DIGEST_LEN);
+    gcry_md_close(c);
+    return SSH_OK;
 }
 
-void sha256(const unsigned char *digest, int len, unsigned char *hash){
+int sha256(const unsigned char *digest, int len, unsigned char *hash){
   gcry_md_hash_buffer(GCRY_MD_SHA256, hash, digest, len);
+  return SSH_OK;
 }
 
 SHA384CTX sha384_init(void) {
@@ -163,18 +145,35 @@ SHA384CTX sha384_init(void) {
   return ctx;
 }
 
-void sha384_update(SHACTX c, const void *data, unsigned long len) {
+void
+sha384_ctx_free(SHA384CTX c)
+{
+    gcry_md_close(c);
+}
+
+int sha384_update(SHACTX c, const void *data, unsigned long len) {
   gcry_md_write(c, data, len);
+  return SSH_OK;
 }
 
-void sha384_final(unsigned char *md, SHACTX c) {
-  gcry_md_final(c);
-  memcpy(md, gcry_md_read(c, 0), SHA384_DIGEST_LEN);
-  gcry_md_close(c);
+int sha384_final(unsigned char *md, SHACTX c)
+{
+    unsigned char *tmp = NULL;
+
+    gcry_md_final(c);
+    tmp = gcry_md_read(c, 0);
+    if (tmp == NULL) {
+        gcry_md_close(c);
+        return SSH_ERROR;
+    }
+    memcpy(md, tmp, SHA384_DIGEST_LEN);
+    gcry_md_close(c);
+    return SSH_OK;
 }
 
-void sha384(const unsigned char *digest, int len, unsigned char *hash) {
+int sha384(const unsigned char *digest, int len, unsigned char *hash) {
   gcry_md_hash_buffer(GCRY_MD_SHA384, hash, digest, len);
+  return SSH_OK;
 }
 
 SHA512CTX sha512_init(void) {
@@ -184,18 +183,35 @@ SHA512CTX sha512_init(void) {
   return ctx;
 }
 
-void sha512_update(SHACTX c, const void *data, unsigned long len) {
+void
+sha512_ctx_free(SHA512CTX c)
+{
+    gcry_md_close(c);
+}
+
+int sha512_update(SHACTX c, const void *data, unsigned long len) {
   gcry_md_write(c, data, len);
+  return SSH_OK;
 }
 
-void sha512_final(unsigned char *md, SHACTX c) {
-  gcry_md_final(c);
-  memcpy(md, gcry_md_read(c, 0), SHA512_DIGEST_LEN);
-  gcry_md_close(c);
+int sha512_final(unsigned char *md, SHACTX c)
+{
+    unsigned char *tmp = NULL;
+
+    gcry_md_final(c);
+    tmp = gcry_md_read(c, 0);
+    if (tmp == NULL) {
+        gcry_md_close(c);
+        return SSH_ERROR;
+    }
+    memcpy(md, tmp, SHA512_DIGEST_LEN);
+    gcry_md_close(c);
+    return SSH_OK;
 }
 
-void sha512(const unsigned char *digest, int len, unsigned char *hash) {
+int sha512(const unsigned char *digest, int len, unsigned char *hash) {
   gcry_md_hash_buffer(GCRY_MD_SHA512, hash, digest, len);
+  return SSH_OK;
 }
 
 MD5CTX md5_init(void) {
@@ -205,14 +221,30 @@ MD5CTX md5_init(void) {
   return c;
 }
 
-void md5_update(MD5CTX c, const void *data, unsigned long len) {
-    gcry_md_write(c,data,len);
+void
+md5_ctx_free(MD5CTX c)
+{
+    gcry_md_close(c);
 }
 
-void md5_final(unsigned char *md, MD5CTX c) {
-  gcry_md_final(c);
-  memcpy(md, gcry_md_read(c, 0), MD5_DIGEST_LEN);
-  gcry_md_close(c);
+int md5_update(MD5CTX c, const void *data, unsigned long len) {
+    gcry_md_write(c,data,len);
+    return SSH_OK;
+}
+
+int md5_final(unsigned char *md, MD5CTX c)
+{
+    unsigned char *tmp = NULL;
+
+    gcry_md_final(c);
+    tmp = gcry_md_read(c, 0);
+    if (tmp == NULL) {
+        gcry_md_close(c);
+        return SSH_ERROR;
+    }
+    memcpy(md, tmp, MD5_DIGEST_LEN);
+    gcry_md_close(c);
+    return SSH_OK;
 }
 
 int ssh_kdf(struct ssh_crypto_struct *crypto,

src/libmbedcrypto.c

@@ -82,99 +82,46 @@ SHACTX sha1_init(void)
     return ctx;
 }
 
-void sha1_update(SHACTX c, const void *data, unsigned long len)
+void
+sha1_ctx_free(SHACTX c)
 {
-    mbedtls_md_update(c, data, len);
-}
-
-void sha1_final(unsigned char *md, SHACTX c)
-{
-    mbedtls_md_finish(c, md);
     mbedtls_md_free(c);
     SAFE_FREE(c);
 }
 
-void sha1(const unsigned char *digest, int len, unsigned char *hash)
+int sha1_update(SHACTX c, const void *data, unsigned long len)
+{
+    int rc = mbedtls_md_update(c, data, len);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha1_final(unsigned char *md, SHACTX c)
+{
+    int rc = mbedtls_md_finish(c, md);
+    sha1_ctx_free(c);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha1(const unsigned char *digest, int len, unsigned char *hash)
 {
     const mbedtls_md_info_t *md_info =
         mbedtls_md_info_from_type(MBEDTLS_MD_SHA1);
-    if (md_info != NULL) {
-        mbedtls_md(md_info, digest, len, hash);
-    }
-}
-
-static mbedtls_md_type_t nid_to_md_algo(int nid)
-{
-    switch (nid) {
-        case NID_mbedtls_nistp256:
-            return MBEDTLS_MD_SHA256;
-        case NID_mbedtls_nistp384:
-            return MBEDTLS_MD_SHA384;
-        case NID_mbedtls_nistp521:
-            return MBEDTLS_MD_SHA512;
-    }
-    return MBEDTLS_MD_NONE;
-}
-
-void evp(int nid, unsigned char *digest, int len,
-        unsigned char *hash, unsigned int *hlen)
-{
-    mbedtls_md_type_t algo = nid_to_md_algo(nid);
-    const mbedtls_md_info_t *md_info =
-        mbedtls_md_info_from_type(algo);
-
-
-    if (md_info != NULL) {
-        *hlen = mbedtls_md_get_size(md_info);
-        mbedtls_md(md_info, digest, len, hash);
-    }
-}
-
-EVPCTX evp_init(int nid)
-{
-    EVPCTX ctx = NULL;
     int rc;
-    mbedtls_md_type_t algo = nid_to_md_algo(nid);
-    const mbedtls_md_info_t *md_info =
-        mbedtls_md_info_from_type(algo);
 
     if (md_info == NULL) {
-        return NULL;
+        return SSH_ERROR;
     }
-
-    ctx = malloc(sizeof(mbedtls_md_context_t));
-    if (ctx == NULL) {
-        return NULL;
-    }
-
-    mbedtls_md_init(ctx);
-
-    rc = mbedtls_md_setup(ctx, md_info, 0);
+    rc = mbedtls_md(md_info, digest, len, hash);
     if (rc != 0) {
-        SAFE_FREE(ctx);
-        return NULL;
+        return SSH_ERROR;
     }
-
-    rc = mbedtls_md_starts(ctx);
-    if (rc != 0) {
-        SAFE_FREE(ctx);
-        return NULL;
-    }
-
-    return ctx;
-}
-
-void evp_update(EVPCTX ctx, const void *data, unsigned long len)
-{
-    mbedtls_md_update(ctx, data, len);
-}
-
-void evp_final(EVPCTX ctx, unsigned char *md, unsigned int *mdlen)
-{
-    *mdlen = mbedtls_md_get_size(ctx->md_info);
-    mbedtls_md_finish(ctx, md);
-    mbedtls_md_free(ctx);
-    SAFE_FREE(ctx);
+    return SSH_OK;
 }
 
 SHA256CTX sha256_init(void)
@@ -210,25 +157,46 @@ SHA256CTX sha256_init(void)
     return ctx;
 }
 
-void sha256_update(SHA256CTX c, const void *data, unsigned long len)
+void
+sha256_ctx_free(SHA256CTX c)
 {
-    mbedtls_md_update(c, data, len);
-}
-
-void sha256_final(unsigned char *md, SHA256CTX c)
-{
-    mbedtls_md_finish(c, md);
     mbedtls_md_free(c);
     SAFE_FREE(c);
 }
 
-void sha256(const unsigned char *digest, int len, unsigned char *hash)
+int sha256_update(SHA256CTX c, const void *data, unsigned long len)
+{
+    int rc = mbedtls_md_update(c, data, len);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha256_final(unsigned char *md, SHA256CTX c)
+{
+    int rc = mbedtls_md_finish(c, md);
+    sha256_ctx_free(c);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha256(const unsigned char *digest, int len, unsigned char *hash)
 {
     const mbedtls_md_info_t *md_info =
         mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
-    if (md_info != NULL) {
-        mbedtls_md(md_info, digest, len, hash);
+    int rc;
+
+    if (md_info == NULL) {
+        return SSH_ERROR;
     }
+    rc = mbedtls_md(md_info, digest, len, hash);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
 }
 
 SHA384CTX sha384_init(void)
@@ -264,25 +232,46 @@ SHA384CTX sha384_init(void)
     return ctx;
 }
 
-void sha384_update(SHA384CTX c, const void *data, unsigned long len)
+void
+sha384_ctx_free(SHA384CTX c)
 {
-    mbedtls_md_update(c, data, len);
-}
-
-void sha384_final(unsigned char *md, SHA384CTX c)
-{
-    mbedtls_md_finish(c, md);
     mbedtls_md_free(c);
     SAFE_FREE(c);
 }
 
-void sha384(const unsigned char *digest, int len, unsigned char *hash)
+int sha384_update(SHA384CTX c, const void *data, unsigned long len)
+{
+    int rc = mbedtls_md_update(c, data, len);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha384_final(unsigned char *md, SHA384CTX c)
+{
+    int rc = mbedtls_md_finish(c, md);
+    sha384_ctx_free(c);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha384(const unsigned char *digest, int len, unsigned char *hash)
 {
     const mbedtls_md_info_t *md_info =
         mbedtls_md_info_from_type(MBEDTLS_MD_SHA384);
-    if (md_info != NULL) {
-        mbedtls_md(md_info, digest, len, hash);
+    int rc;
+
+    if (md_info == NULL) {
+        return SSH_ERROR;
     }
+    rc = mbedtls_md(md_info, digest, len, hash);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
 }
 
 SHA512CTX sha512_init(void)
@@ -317,25 +306,46 @@ SHA512CTX sha512_init(void)
     return ctx;
 }
 
-void sha512_update(SHA512CTX c, const void *data, unsigned long len)
+void
+sha512_ctx_free(SHA512CTX c)
 {
-    mbedtls_md_update(c, data, len);
-}
-
-void sha512_final(unsigned char *md, SHA512CTX c)
-{
-    mbedtls_md_finish(c, md);
     mbedtls_md_free(c);
     SAFE_FREE(c);
 }
 
-void sha512(const unsigned char *digest, int len, unsigned char *hash)
+int sha512_update(SHA512CTX c, const void *data, unsigned long len)
+{
+    int rc = mbedtls_md_update(c, data, len);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha512_final(unsigned char *md, SHA512CTX c)
+{
+    int rc = mbedtls_md_finish(c, md);
+    sha512_ctx_free(c);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int sha512(const unsigned char *digest, int len, unsigned char *hash)
 {
     const mbedtls_md_info_t *md_info =
         mbedtls_md_info_from_type(MBEDTLS_MD_SHA512);
-    if (md_info != NULL) {
-        mbedtls_md(md_info, digest, len, hash);
+    int rc;
+
+    if (md_info == NULL) {
+        return SSH_ERROR;
     }
+    rc = mbedtls_md(md_info, digest, len, hash);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
 }
 
 MD5CTX md5_init(void)
@@ -370,18 +380,32 @@ MD5CTX md5_init(void)
     return ctx;
 }
 
-
-void md5_update(MD5CTX c, const void *data, unsigned long len) {
-    mbedtls_md_update(c, data, len);
-}
-
-void md5_final(unsigned char *md, MD5CTX c)
+void
+md5_ctx_free(MD5CTX c)
 {
-    mbedtls_md_finish(c, md);
     mbedtls_md_free(c);
     SAFE_FREE(c);
 }
 
+int md5_update(MD5CTX c, const void *data, unsigned long len)
+{
+    int rc = mbedtls_md_update(c, data, len);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
+int md5_final(unsigned char *md, MD5CTX c)
+{
+    int rc = mbedtls_md_finish(c, md);
+    md5_ctx_free(c);
+    if (rc != 0) {
+        return SSH_ERROR;
+    }
+    return SSH_OK;
+}
+
 int ssh_kdf(struct ssh_crypto_struct *crypto,
             unsigned char *key, size_t key_len,
             int key_type, unsigned char *output,

src/misc.c

@@ -32,6 +32,7 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#include <net/if.h>
 
 #endif /* _WIN32 */
 
@@ -59,6 +60,7 @@
 #include <ws2tcpip.h>
 #include <shlobj.h>
 #include <direct.h>
+#include <netioapi.h>
 
 #ifdef HAVE_IO_H
 #include <io.h>
@@ -94,6 +96,8 @@
 #define ZLIB_STRING ""
 #endif
 
+#define ARPA_DOMAIN_MAX_LEN 63
+
 /**
  * @defgroup libssh_misc The SSH helper functions.
  * @ingroup libssh
@@ -214,22 +218,37 @@ int ssh_is_ipaddr_v4(const char *str) {
 
 int ssh_is_ipaddr(const char *str) {
     int rc = SOCKET_ERROR;
+    char *s = strdup(str);
 
-    if (strchr(str, ':')) {
+    if (s == NULL) {
+        return -1;
+    }
+    if (strchr(s, ':')) {
         struct sockaddr_storage ss;
         int sslen = sizeof(ss);
+        char *network_interface = strchr(s, '%');
 
-        /* TODO link-local (IP:v6:addr%ifname). */
-        rc = WSAStringToAddressA((LPSTR) str,
+        /* link-local (IP:v6:addr%ifname). */
+        if (network_interface != NULL) {
+            rc = if_nametoindex(network_interface + 1);
+            if (rc == 0) {
+                free(s);
+                return 0;
+            }
+            *network_interface = '\0';
+        }
+        rc = WSAStringToAddressA((LPSTR) s,
                                  AF_INET6,
                                  NULL,
                                  (struct sockaddr*)&ss,
                                  &sslen);
         if (rc == 0) {
+            free(s);
             return 1;
         }
     }
 
+    free(s);
     return ssh_is_ipaddr_v4(str);
 }
 #else /* _WIN32 */
@@ -333,17 +352,32 @@ int ssh_is_ipaddr_v4(const char *str) {
 
 int ssh_is_ipaddr(const char *str) {
     int rc = -1;
+    char *s = strdup(str);
 
-    if (strchr(str, ':')) {
+    if (s == NULL) {
+        return -1;
+    }
+    if (strchr(s, ':')) {
         struct in6_addr dest6;
+        char *network_interface = strchr(s, '%');
 
-        /* TODO link-local (IP:v6:addr%ifname). */
-        rc = inet_pton(AF_INET6, str, &dest6);
+        /* link-local (IP:v6:addr%ifname). */
+        if (network_interface != NULL) {
+            rc = if_nametoindex(network_interface + 1);
+            if (rc == 0) {
+                free(s);
+                return 0;
+            }
+            *network_interface = '\0';
+        }
+        rc = inet_pton(AF_INET6, s, &dest6);
         if (rc > 0) {
+            free(s);
             return 1;
         }
     }
 
+    free(s);
     return ssh_is_ipaddr_v4(str);
 }
 
@@ -1164,14 +1198,13 @@ char *ssh_path_expand_escape(ssh_session session, const char *s) {
                 x = strdup(session->opts.username);
                 break;
             case 'p':
-                if (session->opts.port < 65536) {
-                    char tmp[6];
+                {
+                  char tmp[6];
 
-                    snprintf(tmp,
-                             sizeof(tmp),
-                             "%u",
-                             session->opts.port > 0 ? session->opts.port : 22);
-                    x = strdup(tmp);
+                  snprintf(tmp, sizeof(tmp), "%hu",
+                           (uint16_t)(session->opts.port > 0 ? session->opts.port
+                                                             : 22));
+                  x = strdup(tmp);
                 }
                 break;
             default:
@@ -1735,4 +1768,70 @@ int ssh_newline_vis(const char *string, char *buf, size_t buf_len)
     return out - buf;
 }
 
+/**
+ * @brief Checks syntax of a domain name
+ *
+ * The check is made based on the RFC1035 section 2.3.1
+ * Allowed characters are: hyphen, period, digits (0-9) and letters (a-zA-Z)
+ *
+ * The label should be no longer than 63 characters
+ * The label should start with a letter and end with a letter or number
+ * The label in this implementation can start with a number to allow virtual
+ * URLs to pass. Note that this will make IPv4 addresses to pass
+ * this check too.
+ *
+ * @param hostname The domain name to be checked, has to be null terminated
+ *
+ * @return SSH_OK if the hostname passes syntax check
+ *         SSH_ERROR otherwise or if hostname is NULL or empty string
+ */
+int ssh_check_hostname_syntax(const char *hostname)
+{
+    char *it = NULL, *s = NULL, *buf = NULL;
+    size_t it_len;
+    char c;
+
+    if (hostname == NULL || strlen(hostname) == 0) {
+        return SSH_ERROR;
+    }
+
+    /* strtok_r writes into the string, keep the input clean */
+    s = strdup(hostname);
+    if (s == NULL) {
+        return SSH_ERROR;
+    }
+
+    it = strtok_r(s, ".", &buf);
+    /* if the token has 0 length */
+    if (it == NULL) {
+        free(s);
+        return SSH_ERROR;
+    }
+    do {
+        it_len = strlen(it);
+        if (it_len > ARPA_DOMAIN_MAX_LEN ||
+            /* the first char must be a letter, but some virtual urls start
+             * with a number */
+            isalnum(it[0]) == 0 ||
+            isalnum(it[it_len - 1]) == 0) {
+            free(s);
+            return SSH_ERROR;
+        }
+        while (*it != '\0') {
+            c = *it;
+            /* the "." is allowed too, but tokenization removes it from the
+             * string */
+            if (isalnum(c) == 0 && c != '-') {
+                free(s);
+                return SSH_ERROR;
+            }
+            it++;
+        }
+    } while ((it = strtok_r(NULL, ".", &buf)) != NULL);
+
+    free(s);
+
+    return SSH_OK;
+}
+
 /** @} */

src/options.c

@@ -36,6 +36,7 @@
 #include "libssh/session.h"
 #include "libssh/misc.h"
 #include "libssh/options.h"
+#include "libssh/config_parser.h"
 #ifdef WITH_SERVER
 #include "libssh/server.h"
 #include "libssh/bind.h"
@@ -490,33 +491,24 @@ int ssh_options_set(ssh_session session, enum ssh_options_e type,
                 ssh_set_error_invalid(session);
                 return -1;
             } else {
-                q = strdup(value);
-                if (q == NULL) {
-                    ssh_set_error_oom(session);
+                char *username = NULL, *hostname = NULL, *port = NULL;
+                rc = ssh_config_parse_uri(value, &username, &hostname, &port);
+                if (rc != SSH_OK) {
                     return -1;
                 }
-                p = strchr(q, '@');
-
-                SAFE_FREE(session->opts.host);
-
-                if (p) {
-                    *p = '\0';
-                    session->opts.host = strdup(p + 1);
-                    if (session->opts.host == NULL) {
-                        SAFE_FREE(q);
-                        ssh_set_error_oom(session);
-                        return -1;
-                    }
-
+                if (port != NULL) {
+                    SAFE_FREE(username);
+                    SAFE_FREE(hostname);
+                    SAFE_FREE(port);
+                    return -1;
+                }
+                if (username != NULL) {
                     SAFE_FREE(session->opts.username);
-                    session->opts.username = strdup(q);
-                    SAFE_FREE(q);
-                    if (session->opts.username == NULL) {
-                        ssh_set_error_oom(session);
-                        return -1;
-                    }
-                } else {
-                    session->opts.host = q;
+                    session->opts.username = username;
+                }
+                if (hostname != NULL) {
+                    SAFE_FREE(session->opts.host);
+                    session->opts.host = hostname;
                 }
             }
             break;

src/packet.c

@@ -366,6 +366,11 @@ static enum ssh_packet_filter_result_e ssh_packet_incoming_filter(ssh_session se
          * - session->dh_handhsake_state = DH_STATE_NEWKEYS_SENT
          * */
 
+        if (!session->server) {
+            rc = SSH_PACKET_DENIED;
+            break;
+        }
+
         if (session->session_state != SSH_SESSION_STATE_DH) {
             rc = SSH_PACKET_DENIED;
             break;
@@ -1304,6 +1309,19 @@ int ssh_packet_socket_callback(const void *data, size_t receivedlen, void *user)
             }
 #endif /* WITH_ZLIB */
             payloadsize = ssh_buffer_get_len(session->in_buffer);
+            if (session->recv_seq == UINT32_MAX) {
+                /* Overflowing sequence numbers is always fishy */
+                if (crypto == NULL) {
+                    /* don't allow sequence number overflow when unencrypted */
+                    ssh_set_error(session,
+                                  SSH_FATAL,
+                                  "Incoming sequence number overflow");
+                    goto error;
+                } else {
+                    SSH_LOG(SSH_LOG_WARNING,
+                            "Incoming sequence number overflow");
+                }
+            }
             session->recv_seq++;
             if (crypto != NULL) {
                 struct ssh_cipher_struct *cipher = NULL;
@@ -1326,7 +1344,19 @@ int ssh_packet_socket_callback(const void *data, size_t receivedlen, void *user)
             SSH_LOG(SSH_LOG_PACKET,
                     "packet: read type %hhd [len=%d,padding=%hhd,comp=%d,payload=%d]",
                     session->in_packet.type, packet_len, padding, compsize, payloadsize);
+            if (crypto == NULL) {
+                /* In strict kex, only a few packets are allowed. Taint the session
+                 * if we received packets that are normally allowed but to be
+                 * refused if we are in strict kex when KEX is over.
+                 */
+                uint8_t type = session->in_packet.type;
 
+                if (type != SSH2_MSG_KEXINIT && type != SSH2_MSG_NEWKEYS &&
+                    (type < SSH2_MSG_KEXDH_INIT ||
+                     type > SSH2_MSG_KEX_DH_GEX_REQUEST)) {
+                    session->flags |= SSH_SESSION_FLAG_KEX_TAINTED;
+                }
+            }
             /* Check if the packet is expected */
             filter_result = ssh_packet_incoming_filter(session);
 
@@ -1342,6 +1372,9 @@ int ssh_packet_socket_callback(const void *data, size_t receivedlen, void *user)
                               session->in_packet.type);
                 goto error;
             case SSH_PACKET_UNKNOWN:
+                if (crypto == NULL) {
+                    session->flags |= SSH_SESSION_FLAG_KEX_TAINTED;
+                }
                 ssh_packet_send_unimplemented(session, session->recv_seq - 1);
                 break;
             }
@@ -1410,18 +1443,23 @@ static void ssh_packet_socket_controlflow_callback(int code, void *userdata)
     }
 }
 
-void ssh_packet_register_socket_callback(ssh_session session, ssh_socket s){
-	session->socket_callbacks.data=ssh_packet_socket_callback;
-	session->socket_callbacks.connected=NULL;
-    session->socket_callbacks.controlflow = ssh_packet_socket_controlflow_callback;
-	session->socket_callbacks.userdata=session;
-	ssh_socket_set_callbacks(s,&session->socket_callbacks);
+void ssh_packet_register_socket_callback(ssh_session session, ssh_socket s)
+{
+    struct ssh_socket_callbacks_struct *callbacks = &session->socket_callbacks;
+
+    callbacks->data = ssh_packet_socket_callback;
+    callbacks->connected = NULL;
+    callbacks->controlflow = ssh_packet_socket_controlflow_callback;
+    callbacks->userdata = session;
+    ssh_socket_set_callbacks(s, callbacks);
 }
 
 /** @internal
  * @brief sets the callbacks for the packet layer
  */
-void ssh_packet_set_callbacks(ssh_session session, ssh_packet_callbacks callbacks){
+void
+ssh_packet_set_callbacks(ssh_session session, ssh_packet_callbacks callbacks)
+{
     if (session->packet_callbacks == NULL) {
         session->packet_callbacks = ssh_list_new();
         if (session->packet_callbacks == NULL) {
@@ -1435,8 +1473,11 @@ void ssh_packet_set_callbacks(ssh_session session, ssh_packet_callbacks callback
 /** @internal
  * @brief remove the callbacks from the packet layer
  */
-void ssh_packet_remove_callbacks(ssh_session session, ssh_packet_callbacks callbacks){
+void
+ssh_packet_remove_callbacks(ssh_session session, ssh_packet_callbacks callbacks)
+{
     struct ssh_iterator *it = NULL;
+
     it = ssh_list_find(session->packet_callbacks, callbacks);
     if (it != NULL) {
         ssh_list_remove(session->packet_callbacks, it);
@@ -1446,12 +1487,15 @@ void ssh_packet_remove_callbacks(ssh_session session, ssh_packet_callbacks callb
 /** @internal
  * @brief sets the default packet handlers
  */
-void ssh_packet_set_default_callbacks(ssh_session session){
-	session->default_packet_callbacks.start=1;
-	session->default_packet_callbacks.n_callbacks=sizeof(default_packet_handlers)/sizeof(ssh_packet_callback);
-	session->default_packet_callbacks.user=session;
-	session->default_packet_callbacks.callbacks=default_packet_handlers;
-	ssh_packet_set_callbacks(session, &session->default_packet_callbacks);
+void ssh_packet_set_default_callbacks(ssh_session session)
+{
+    struct ssh_packet_callbacks_struct *c = &session->default_packet_callbacks;
+
+    c->start = 1;
+    c->n_callbacks = sizeof(default_packet_handlers) / sizeof(ssh_packet_callback);
+    c->user = session;
+    c->callbacks = default_packet_handlers;
+    ssh_packet_set_callbacks(session, c);
 }
 
 /** @internal
@@ -1505,9 +1549,35 @@ void ssh_packet_process(ssh_session session, uint8_t type)
             SSH_LOG(SSH_LOG_RARE, "Failed to send unimplemented: %s",
                     ssh_get_error(session));
         }
+        if (session->current_crypto == NULL) {
+            session->flags |= SSH_SESSION_FLAG_KEX_TAINTED;
+        }
     }
 }
 
+/** @internal
+ * @brief sends a SSH_MSG_NEWKEYS when enabling the new negotiated ciphers
+ * @param session the SSH session
+ * @return SSH_ERROR on error, else SSH_OK
+ */
+int ssh_packet_send_newkeys(ssh_session session)
+{
+    int rc;
+
+    /* Send the MSG_NEWKEYS */
+    rc = ssh_buffer_add_u8(session->out_buffer, SSH2_MSG_NEWKEYS);
+    if (rc < 0) {
+        return rc;
+    }
+
+    rc = ssh_packet_send(session);
+    if (rc == SSH_ERROR) {
+        return rc;
+    }
+    SSH_LOG(SSH_LOG_DEBUG, "SSH_MSG_NEWKEYS sent");
+    return rc;
+}
+
 /** @internal
  * @brief sends a SSH_MSG_UNIMPLEMENTED answer to an unhandled packet
  * @param session the SSH session
@@ -1813,6 +1883,10 @@ int ssh_packet_send(ssh_session session)
     if (rc == SSH_OK && type == SSH2_MSG_NEWKEYS) {
         struct ssh_iterator *it;
 
+        if (session->flags & SSH_SESSION_FLAG_KEX_STRICT) {
+            /* reset packet sequence number when running in strict kex mode */
+            session->send_seq = 0;
+        }
         for (it = ssh_list_get_iterator(session->out_queue);
              it != NULL;
              it = ssh_list_get_iterator(session->out_queue)) {
@@ -1926,7 +2000,7 @@ ssh_packet_set_newkeys(ssh_session session,
         memcpy(session->next_crypto->session_id,
                session->current_crypto->session_id,
                session_id_len);
-	session->next_crypto->session_id_len = session_id_len;
+        session->next_crypto->session_id_len = session_id_len;
 
         return SSH_OK;
     }

src/packet_cb.c

@@ -110,6 +110,18 @@ SSH_PACKET_CALLBACK(ssh_packet_newkeys){
       goto error;
   }
 
+  if (session->flags & SSH_SESSION_FLAG_KEX_STRICT) {
+      /* reset packet sequence number when running in strict kex mode */
+      session->recv_seq = 0;
+      /* Check that we aren't tainted */
+      if (session->flags & SSH_SESSION_FLAG_KEX_TAINTED) {
+          ssh_set_error(session,
+                        SSH_FATAL,
+                        "Received unexpected packets in strict KEX mode.");
+          goto error;
+      }
+  }
+
   if(session->server){
     /* server things are done in server.c */
     session->dh_handshake_state=DH_STATE_FINISHED;
@@ -156,6 +168,9 @@ SSH_PACKET_CALLBACK(ssh_packet_newkeys){
                                   session->next_crypto->digest_len);
     SSH_SIGNATURE_FREE(sig);
     if (rc == SSH_ERROR) {
+      ssh_set_error(session,
+                    SSH_FATAL,
+                    "Failed to verify server hostkey signature");
       goto error;
     }
     SSH_LOG(SSH_LOG_PROTOCOL,"Signature verified and valid");

src/pki_crypto.c

@@ -2291,8 +2291,12 @@ int pki_verify_data_signature(ssh_signature signature,
     unsigned char *raw_sig_data = NULL;
     unsigned int raw_sig_len;
 
+    /* Function return code
+     * Do not change this variable throughout the function until the signature
+     * is successfully verified!
+     */
     int rc = SSH_ERROR;
-    int evp_rc;
+    int ok;
 
     if (pubkey == NULL || ssh_key_is_private(pubkey) || input == NULL ||
         signature == NULL || (signature->raw_sig == NULL
@@ -2307,8 +2311,8 @@ int pki_verify_data_signature(ssh_signature signature,
     }
 
     /* Check if public key and hash type are compatible */
-    rc = pki_key_check_hash_compatible(pubkey, signature->hash_type);
-    if (rc != SSH_OK) {
+    ok = pki_key_check_hash_compatible(pubkey, signature->hash_type);
+    if (ok != SSH_OK) {
         return SSH_ERROR;
     }
 
@@ -2351,8 +2355,8 @@ int pki_verify_data_signature(ssh_signature signature,
     }
 
     /* Verify the signature */
-    evp_rc = EVP_DigestVerifyInit(ctx, NULL, md, NULL, pkey);
-    if (evp_rc != 1){
+    ok = EVP_DigestVerifyInit(ctx, NULL, md, NULL, pkey);
+    if (ok != 1){
         SSH_LOG(SSH_LOG_TRACE,
                 "EVP_DigestVerifyInit() failed: %s",
                 ERR_error_string(ERR_get_error(), NULL));
@@ -2360,35 +2364,31 @@ int pki_verify_data_signature(ssh_signature signature,
     }
 
 #ifdef HAVE_OPENSSL_EVP_DIGESTVERIFY
-    evp_rc = EVP_DigestVerify(ctx, raw_sig_data, raw_sig_len, input, input_len);
+    ok = EVP_DigestVerify(ctx, raw_sig_data, raw_sig_len, input, input_len);
 #else
-    evp_rc = EVP_DigestVerifyUpdate(ctx, input, input_len);
-    if (evp_rc != 1) {
+    ok = EVP_DigestVerifyUpdate(ctx, input, input_len);
+    if (ok != 1) {
         SSH_LOG(SSH_LOG_TRACE,
                 "EVP_DigestVerifyUpdate() failed: %s",
                 ERR_error_string(ERR_get_error(), NULL));
         goto out;
     }
 
-    evp_rc = EVP_DigestVerifyFinal(ctx, raw_sig_data, raw_sig_len);
+    ok = EVP_DigestVerifyFinal(ctx, raw_sig_data, raw_sig_len);
 #endif
-    if (evp_rc == 1) {
-        SSH_LOG(SSH_LOG_TRACE, "Signature valid");
-        rc = SSH_OK;
-    } else {
+    if (ok != 1) {
         SSH_LOG(SSH_LOG_TRACE,
                 "Signature invalid: %s",
                 ERR_error_string(ERR_get_error(), NULL));
-        rc = SSH_ERROR;
+        goto out;
     }
 
+    SSH_LOG(SSH_LOG_TRACE, "Signature valid");
+    rc = SSH_OK;
+
 out:
-    if (ctx != NULL) {
-        EVP_MD_CTX_free(ctx);
-    }
-    if (pkey != NULL) {
-        EVP_PKEY_free(pkey);
-    }
+    EVP_MD_CTX_free(ctx);
+    EVP_PKEY_free(pkey);
     return rc;
 }
 

src/server.c

@@ -92,7 +92,11 @@ int server_set_kex(ssh_session session)
     size_t len;
     int ok;
 
-    ZERO_STRUCTP(server);
+    /* Skip if already set, for example for the rekey or when we do the guessing
+     * it could have been already used to make some protocol decisions. */
+    if (server->methods[0] != NULL) {
+        return SSH_OK;
+    }
 
     ok = ssh_get_random(server->cookie, 16, 0);
     if (!ok) {
@@ -191,7 +195,13 @@ int server_set_kex(ssh_session session)
         }
     }
 
-    return 0;
+    /* Do not append the extensions during rekey */
+    if (session->flags & SSH_SESSION_FLAG_AUTHENTICATED) {
+        return SSH_OK;
+    }
+
+    rc = ssh_kex_append_extensions(session, server);
+    return rc;
 }
 
 int ssh_server_init_kex(ssh_session session) {
@@ -335,117 +345,121 @@ ssh_get_key_params(ssh_session session,
  * @brief A function to be called each time a step has been done in the
  * connection.
  */
-static void ssh_server_connection_callback(ssh_session session){
+static void ssh_server_connection_callback(ssh_session session)
+{
     int rc;
 
-    switch(session->session_state){
-        case SSH_SESSION_STATE_NONE:
-        case SSH_SESSION_STATE_CONNECTING:
-        case SSH_SESSION_STATE_SOCKET_CONNECTED:
-            break;
-        case SSH_SESSION_STATE_BANNER_RECEIVED:
-            if (session->clientbanner == NULL) {
-                goto error;
-            }
-            set_status(session, 0.4f);
-            SSH_LOG(SSH_LOG_PROTOCOL,
-                    "SSH client banner: %s", session->clientbanner);
+    switch (session->session_state) {
+    case SSH_SESSION_STATE_NONE:
+    case SSH_SESSION_STATE_CONNECTING:
+    case SSH_SESSION_STATE_SOCKET_CONNECTED:
+        break;
+    case SSH_SESSION_STATE_BANNER_RECEIVED:
+        if (session->clientbanner == NULL) {
+            goto error;
+        }
+        set_status(session, 0.4f);
+        SSH_LOG(SSH_LOG_PROTOCOL,
+                "SSH client banner: %s", session->clientbanner);
 
-            /* Here we analyze the different protocols the server allows. */
-            rc = ssh_analyze_banner(session, 1);
-            if (rc < 0) {
-                ssh_set_error(session, SSH_FATAL,
-                        "No version of SSH protocol usable (banner: %s)",
-                        session->clientbanner);
+        /* Here we analyze the different protocols the server allows. */
+        rc = ssh_analyze_banner(session, 1);
+        if (rc < 0) {
+            ssh_set_error(session, SSH_FATAL,
+                          "No version of SSH protocol usable (banner: %s)",
+                          session->clientbanner);
+            goto error;
+        }
+
+        /* from now, the packet layer is handling incoming packets */
+        session->socket_callbacks.data = ssh_packet_socket_callback;
+        ssh_packet_register_socket_callback(session, session->socket);
+
+        ssh_packet_set_default_callbacks(session);
+        set_status(session, 0.5f);
+        session->session_state = SSH_SESSION_STATE_INITIAL_KEX;
+        if (ssh_send_kex(session) < 0) {
+            goto error;
+        }
+        break;
+    case SSH_SESSION_STATE_INITIAL_KEX:
+        /* TODO: This state should disappear in favor of get_key handle */
+        break;
+    case SSH_SESSION_STATE_KEXINIT_RECEIVED:
+        set_status(session, 0.6f);
+        if ((session->flags & SSH_SESSION_FLAG_KEXINIT_SENT) == 0) {
+            if (server_set_kex(session) == SSH_ERROR)
+                goto error;
+            /* We are in a rekeying, so we need to send the server kex */
+            if (ssh_send_kex(session) < 0)
+                goto error;
+        }
+        ssh_list_kex(&session->next_crypto->client_kex); // log client kex
+        if (ssh_kex_select_methods(session) < 0) {
+            goto error;
+        }
+        if (crypt_set_algorithms_server(session) == SSH_ERROR)
+            goto error;
+        set_status(session, 0.8f);
+        session->session_state = SSH_SESSION_STATE_DH;
+        break;
+    case SSH_SESSION_STATE_DH:
+        if (session->dh_handshake_state == DH_STATE_FINISHED) {
+
+            rc = ssh_packet_set_newkeys(session, SSH_DIRECTION_IN);
+            if (rc != SSH_OK) {
                 goto error;
             }
 
-            /* from now, the packet layer is handling incoming packets */
-            session->socket_callbacks.data=ssh_packet_socket_callback;
-            ssh_packet_register_socket_callback(session, session->socket);
-
-            ssh_packet_set_default_callbacks(session);
-            set_status(session, 0.5f);
-            session->session_state=SSH_SESSION_STATE_INITIAL_KEX;
-            if (ssh_send_kex(session, 1) < 0) {
-                goto error;
-            }
-            break;
-        case SSH_SESSION_STATE_INITIAL_KEX:
-            /* TODO: This state should disappear in favor of get_key handle */
-            break;
-        case SSH_SESSION_STATE_KEXINIT_RECEIVED:
-            set_status(session,0.6f);
-            if(session->next_crypto->server_kex.methods[0]==NULL){
-                if(server_set_kex(session) == SSH_ERROR)
-                    goto error;
-                /* We are in a rekeying, so we need to send the server kex */
-                if(ssh_send_kex(session, 1) < 0)
-                    goto error;
-            }
-            ssh_list_kex(&session->next_crypto->client_kex); // log client kex
-            if (ssh_kex_select_methods(session) < 0) {
-                goto error;
-            }
-            if (crypt_set_algorithms_server(session) == SSH_ERROR)
-                goto error;
-            set_status(session,0.8f);
-            session->session_state=SSH_SESSION_STATE_DH;
-            break;
-        case SSH_SESSION_STATE_DH:
-            if(session->dh_handshake_state==DH_STATE_FINISHED){
-
-                rc = ssh_packet_set_newkeys(session, SSH_DIRECTION_IN);
-                if (rc != SSH_OK) {
-                    goto error;
-                }
+            /*
+             * If the client supports extension negotiation, we will send
+             * our supported extensions now. This is the first message after
+             * sending NEWKEYS message and after turning on crypto.
+             */
+            if (session->extensions & SSH_EXT_NEGOTIATION &&
+                session->session_state != SSH_SESSION_STATE_AUTHENTICATED) {
 
                 /*
-                 * If the client supports extension negotiation, we will send
-                 * our supported extensions now. This is the first message after
-                 * sending NEWKEYS message and after turning on crypto.
+                 * Only send an SSH_MSG_EXT_INFO message the first time the
+                 * client undergoes NEWKEYS.  It is unexpected for this message
+                 * to be sent upon rekey, and may cause clients to log error
+                 * messages.
+                 *
+                 * The session_state can not be used for this purpose because it
+                 * is re-set to SSH_SESSION_STATE_KEXINIT_RECEIVED during rekey.
+                 * So, use the connected flag which transitions from non-zero
+                 * below.
+                 *
+                 * See also:
+                 * - https://bugzilla.mindrot.org/show_bug.cgi?id=2929
                  */
-                if (session->extensions & SSH_EXT_NEGOTIATION &&
-                    session->session_state != SSH_SESSION_STATE_AUTHENTICATED) {
-
-                    /*
-                     * Only send an SSH_MSG_EXT_INFO message the first time the client
-                     * undergoes NEWKEYS.  It is unexpected for this message to be sent
-                     * upon rekey, and may cause clients to log error messages.
-                     *
-                     * The session_state can not be used for this purpose because it is
-                     * re-set to SSH_SESSION_STATE_KEXINIT_RECEIVED during rekey.  So,
-                     * use the connected flag which transitions from non-zero below.
-                     *
-                     * See also:
-                     * - https://bugzilla.mindrot.org/show_bug.cgi?id=2929
-                     */
-                    if (session->connected == 0) {
-                        ssh_server_send_extensions(session);
-                    }
+                if (session->connected == 0) {
+                    ssh_server_send_extensions(session);
                 }
-
-                set_status(session,1.0f);
-                session->connected = 1;
-                session->session_state=SSH_SESSION_STATE_AUTHENTICATING;
-                if (session->flags & SSH_SESSION_FLAG_AUTHENTICATED)
-                    session->session_state = SSH_SESSION_STATE_AUTHENTICATED;
-
             }
-            break;
-        case SSH_SESSION_STATE_AUTHENTICATING:
-            break;
-        case SSH_SESSION_STATE_ERROR:
-            goto error;
-        default:
-            ssh_set_error(session,SSH_FATAL,"Invalid state %d",session->session_state);
+
+            set_status(session, 1.0f);
+            session->connected = 1;
+            session->session_state = SSH_SESSION_STATE_AUTHENTICATING;
+            if (session->flags & SSH_SESSION_FLAG_AUTHENTICATED)
+                session->session_state = SSH_SESSION_STATE_AUTHENTICATED;
+
+        }
+        break;
+    case SSH_SESSION_STATE_AUTHENTICATING:
+        break;
+    case SSH_SESSION_STATE_ERROR:
+        goto error;
+    default:
+        ssh_set_error(session, SSH_FATAL, "Invalid state %d",
+                      session->session_state);
     }
 
     return;
 error:
     ssh_socket_close(session->socket);
     session->alive = 0;
-    session->session_state=SSH_SESSION_STATE_ERROR;
+    session->session_state = SSH_SESSION_STATE_ERROR;
 }
 
 /**
@@ -459,16 +473,17 @@ error:
  * @param  user is a pointer to session
  * @returns Number of bytes processed, or zero if the banner is not complete.
  */
-static int callback_receive_banner(const void *data, size_t len, void *user) {
-    char *buffer = (char *) data;
-    ssh_session session = (ssh_session) user;
+static int callback_receive_banner(const void *data, size_t len, void *user)
+{
+    char *buffer = (char *)data;
+    ssh_session session = (ssh_session)user;
     char *str = NULL;
     size_t i;
     int ret=0;
 
     for (i = 0; i < len; i++) {
 #ifdef WITH_PCAP
-        if(session->pcap_ctx && buffer[i] == '\n') {
+        if (session->pcap_ctx && buffer[i] == '\n') {
             ssh_pcap_context_write(session->pcap_ctx,
                                    SSH_PCAP_DIR_IN,
                                    buffer,
@@ -477,11 +492,11 @@ static int callback_receive_banner(const void *data, size_t len, void *user) {
         }
 #endif
         if (buffer[i] == '\r') {
-            buffer[i]='\0';
+            buffer[i] = '\0';
         }
 
         if (buffer[i] == '\n') {
-            buffer[i]='\0';
+            buffer[i] = '\0';
 
             str = strdup(buffer);
             /* number of bytes read */
@@ -494,10 +509,11 @@ static int callback_receive_banner(const void *data, size_t len, void *user) {
             return ret;
         }
 
-        if(i > 127) {
+        if (i > 127) {
             /* Too big banner */
             session->session_state = SSH_SESSION_STATE_ERROR;
-            ssh_set_error(session, SSH_FATAL, "Receiving banner: too large banner");
+            ssh_set_error(session, SSH_FATAL,
+                          "Receiving banner: too large banner");
 
             return 0;
         }
@@ -525,10 +541,14 @@ void ssh_set_auth_methods(ssh_session session, int auth_methods)
 }
 
 /* Do the banner and key exchange */
-int ssh_handle_key_exchange(ssh_session session) {
+int ssh_handle_key_exchange(ssh_session session)
+{
     int rc;
-    if (session->session_state != SSH_SESSION_STATE_NONE)
-      goto pending;
+
+    if (session->session_state != SSH_SESSION_STATE_NONE) {
+        goto pending;
+    }
+
     rc = ssh_send_banner(session, 1);
     if (rc < 0) {
         return SSH_ERROR;
@@ -539,27 +559,28 @@ int ssh_handle_key_exchange(ssh_session session) {
     session->ssh_connection_callback = ssh_server_connection_callback;
     session->session_state = SSH_SESSION_STATE_SOCKET_CONNECTED;
     ssh_socket_set_callbacks(session->socket,&session->socket_callbacks);
-    session->socket_callbacks.data=callback_receive_banner;
-    session->socket_callbacks.exception=ssh_socket_exception_callback;
-    session->socket_callbacks.userdata=session;
+    session->socket_callbacks.data = callback_receive_banner;
+    session->socket_callbacks.exception = ssh_socket_exception_callback;
+    session->socket_callbacks.userdata = session;
 
     rc = server_set_kex(session);
     if (rc < 0) {
         return SSH_ERROR;
     }
-    pending:
+pending:
     rc = ssh_handle_packets_termination(session, SSH_TIMEOUT_USER,
-        ssh_server_kex_termination,session);
+                                        ssh_server_kex_termination,session);
     SSH_LOG(SSH_LOG_PACKET, "ssh_handle_key_exchange: current state : %d",
-        session->session_state);
-    if (rc != SSH_OK)
-      return rc;
+            session->session_state);
+    if (rc != SSH_OK) {
+        return rc;
+    }
     if (session->session_state == SSH_SESSION_STATE_ERROR ||
         session->session_state == SSH_SESSION_STATE_DISCONNECTED) {
-      return SSH_ERROR;
+        return SSH_ERROR;
     }
 
-  return SSH_OK;
+    return SSH_OK;
 }
 
 /* messages */

src/session.c

@@ -643,6 +643,10 @@ int ssh_handle_packets(ssh_session session, int timeout) {
     }
 
     spoll = ssh_socket_get_poll_handle(session->socket);
+    if (spoll == NULL) {
+        ssh_set_error_oom(session);
+        return SSH_ERROR;
+    }
     ssh_poll_add_events(spoll, POLLIN);
     ctx = ssh_poll_get_ctx(spoll);
 
@@ -997,7 +1001,18 @@ int ssh_get_pubkey_hash(ssh_session session, unsigned char **hash)
     *hash = NULL;
     if (session->current_crypto == NULL ||
         session->current_crypto->server_pubkey == NULL) {
-        ssh_set_error(session,SSH_FATAL,"No current cryptographic context");
+        ssh_set_error(session, SSH_FATAL, "No current cryptographic context");
+        return SSH_ERROR;
+    }
+
+    rc = ssh_get_server_publickey(session, &pubkey);
+    if (rc != SSH_OK) {
+        return SSH_ERROR;
+    }
+
+    rc = ssh_pki_export_pubkey_blob(pubkey, &pubkey_blob);
+    ssh_key_free(pubkey);
+    if (rc != SSH_OK) {
         return SSH_ERROR;
     }
 
@@ -1012,24 +1027,20 @@ int ssh_get_pubkey_hash(ssh_session session, unsigned char **hash)
         return SSH_ERROR;
     }
 
-    rc = ssh_get_server_publickey(session, &pubkey);
+    rc = md5_update(ctx,
+                    ssh_string_data(pubkey_blob),
+                    ssh_string_len(pubkey_blob));
     if (rc != SSH_OK) {
-        md5_final(h, ctx);
+        md5_ctx_free(ctx);
         SAFE_FREE(h);
-        return SSH_ERROR;
+        return rc;
     }
-
-    rc = ssh_pki_export_pubkey_blob(pubkey, &pubkey_blob);
-    ssh_key_free(pubkey);
-    if (rc != SSH_OK) {
-        md5_final(h, ctx);
-        SAFE_FREE(h);
-        return SSH_ERROR;
-    }
-
-    md5_update(ctx, ssh_string_data(pubkey_blob), ssh_string_len(pubkey_blob));
     SSH_STRING_FREE(pubkey_blob);
-    md5_final(h, ctx);
+    rc = md5_final(h, ctx);
+    if (rc != SSH_OK) {
+        SAFE_FREE(h);
+        return rc;
+    }
 
     *hash = h;
 
@@ -1149,8 +1160,17 @@ int ssh_get_publickey_hash(const ssh_key key,
                 goto out;
             }
 
-            sha1_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
-            sha1_final(h, ctx);
+            rc = sha1_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
+            if (rc != SSH_OK) {
+                free(h);
+                sha1_ctx_free(ctx);
+                goto out;
+            }
+            rc = sha1_final(h, ctx);
+            if (rc != SSH_OK) {
+                free(h);
+                goto out;
+            }
 
             *hlen = SHA_DIGEST_LEN;
         }
@@ -1172,8 +1192,17 @@ int ssh_get_publickey_hash(const ssh_key key,
                 goto out;
             }
 
-            sha256_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
-            sha256_final(h, ctx);
+            rc = sha256_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
+            if (rc != SSH_OK) {
+                free(h);
+                sha256_ctx_free(ctx);
+                goto out;
+            }
+            rc = sha256_final(h, ctx);
+            if (rc != SSH_OK) {
+                free(h);
+                goto out;
+            }
 
             *hlen = SHA256_DIGEST_LEN;
         }
@@ -1203,8 +1232,17 @@ int ssh_get_publickey_hash(const ssh_key key,
                 goto out;
             }
 
-            md5_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
-            md5_final(h, ctx);
+            rc = md5_update(ctx, ssh_string_data(blob), ssh_string_len(blob));
+            if (rc != SSH_OK) {
+                free(h);
+                md5_ctx_free(ctx);
+                goto out;
+            }
+            rc = md5_final(h, ctx);
+            if (rc != SSH_OK) {
+                free(h);
+                goto out;
+            }
 
             *hlen = MD5_DIGEST_LEN;
         }

src/token.c

@@ -87,7 +87,7 @@ struct ssh_tokens_st *ssh_tokenize(const char *chain, char separator)
         return NULL;
     }
 
-    tokens->buffer= strdup(chain);
+    tokens->buffer = strdup(chain);
     if (tokens->buffer == NULL) {
         goto error;
     }

src/wrapper.c

@@ -147,15 +147,16 @@ static void cipher_free(struct ssh_cipher_struct *cipher) {
   SAFE_FREE(cipher);
 }
 
-struct ssh_crypto_struct *crypto_new(void) {
-   struct ssh_crypto_struct *crypto;
+struct ssh_crypto_struct *crypto_new(void)
+{
+    struct ssh_crypto_struct *crypto;
 
-  crypto = malloc(sizeof(struct ssh_crypto_struct));
-  if (crypto == NULL) {
-    return NULL;
-  }
-  ZERO_STRUCTP(crypto);
-  return crypto;
+    crypto = malloc(sizeof(struct ssh_crypto_struct));
+    if (crypto == NULL) {
+        return NULL;
+    }
+    ZERO_STRUCTP(crypto);
+    return crypto;
 }
 
 void crypto_free(struct ssh_crypto_struct *crypto)

tests/client/torture_auth.c

@@ -200,7 +200,8 @@ static int agent_teardown(void **state)
     assert_non_null(ssh_agent_pidfile);
 
     /* kill agent pid */
-    torture_terminate_process(ssh_agent_pidfile);
+    rc = torture_terminate_process(ssh_agent_pidfile);
+    assert_return_code(rc, errno);
 
     unlink(ssh_agent_pidfile);
 
@@ -551,6 +552,7 @@ static void torture_auth_cert(void **state) {
 
 static void torture_auth_agent_cert(void **state)
 {
+#if OPENSSH_VERSION_MAJOR < 8 || (OPENSSH_VERSION_MAJOR == 8 && OPENSSH_VERSION_MINOR == 0)
     struct torture_state *s = *state;
     ssh_session session = s->ssh.session;
     int rc;
@@ -570,6 +572,7 @@ static void torture_auth_agent_cert(void **state)
                              "ssh-rsa-cert-v01@openssh.com");
         assert_int_equal(rc, SSH_OK);
     }
+#endif /* OPENSSH_VERSION_MAJOR < 8.1 */
 
     /* Setup loads a different key, tests are exactly the same. */
     torture_auth_agent(state);
@@ -577,6 +580,7 @@ static void torture_auth_agent_cert(void **state)
 
 static void torture_auth_agent_cert_nonblocking(void **state)
 {
+#if OPENSSH_VERSION_MAJOR < 8 || (OPENSSH_VERSION_MAJOR == 8 && OPENSSH_VERSION_MINOR == 0)
     struct torture_state *s = *state;
     ssh_session session = s->ssh.session;
     int rc;
@@ -596,6 +600,7 @@ static void torture_auth_agent_cert_nonblocking(void **state)
                              "ssh-rsa-cert-v01@openssh.com");
         assert_int_equal(rc, SSH_OK);
     }
+#endif /* OPENSSH_VERSION_MAJOR < 8.1 */
 
     torture_auth_agent_nonblocking(state);
 }

tests/client/torture_proxycommand.c

@@ -161,6 +161,56 @@ static void torture_options_set_proxycommand_ssh_stderr(void **state)
     assert_int_equal(rc & O_RDWR, O_RDWR);
 }
 
+static void torture_options_proxycommand_injection(void **state)
+{
+    struct torture_state *s = *state;
+    struct passwd *pwd = NULL;
+    const char *malicious_host = "`echo foo > mfile`";
+    const char *command = "nc %h %p";
+    char *current_dir = NULL;
+    char *malicious_file_path = NULL;
+    int mfp_len;
+    int verbosity = torture_libssh_verbosity();
+    struct stat sb;
+    int rc;
+
+    pwd = getpwnam("bob");
+    assert_non_null(pwd);
+
+    rc = setuid(pwd->pw_uid);
+    assert_return_code(rc, errno);
+
+    s->ssh.session = ssh_new();
+    assert_non_null(s->ssh.session);
+
+    ssh_options_set(s->ssh.session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
+    // if we would be checking the rc, this should fail
+    ssh_options_set(s->ssh.session, SSH_OPTIONS_HOST, malicious_host);
+
+    ssh_options_set(s->ssh.session, SSH_OPTIONS_USER, TORTURE_SSH_USER_ALICE);
+
+    rc = ssh_options_set(s->ssh.session, SSH_OPTIONS_PROXYCOMMAND, command);
+    assert_int_equal(rc, 0);
+    rc = ssh_connect(s->ssh.session);
+    assert_ssh_return_code_equal(s->ssh.session, rc, SSH_ERROR);
+
+    current_dir = torture_get_current_working_dir();
+    assert_non_null(current_dir);
+    mfp_len = strlen(current_dir) + 6;
+    malicious_file_path = malloc(mfp_len);
+    assert_non_null(malicious_file_path);
+    rc = snprintf(malicious_file_path, mfp_len,
+                  "%s/mfile", current_dir);
+    assert_int_equal(rc, mfp_len);
+    free(current_dir);
+    rc = stat(malicious_file_path, &sb);
+    assert_int_not_equal(rc, 0);
+
+    // cleanup
+    remove(malicious_file_path);
+    free(malicious_file_path);
+}
+
 int torture_run_tests(void) {
     int rc;
     struct CMUnitTest tests[] = {
@@ -176,6 +226,9 @@ int torture_run_tests(void) {
         cmocka_unit_test_setup_teardown(torture_options_set_proxycommand_ssh_stderr,
                                         session_setup,
                                         session_teardown),
+        cmocka_unit_test_setup_teardown(torture_options_proxycommand_injection,
+                                        NULL,
+                                        session_teardown),
     };
 
 

tests/client/torture_rekey.c

@@ -38,6 +38,8 @@
 #include <fcntl.h>
 #include <pwd.h>
 
+#define KEX_RETRY 32
+
 static uint64_t bytes = 2048; /* 2KB (more than the authentication phase) */
 
 static int sshd_setup(void **state)
@@ -146,6 +148,29 @@ static void torture_rekey_default(void **state)
     ssh_disconnect(s->ssh.session);
 }
 
+static void sanity_check_session(void **state)
+{
+    struct torture_state *s = *state;
+    struct ssh_crypto_struct *c = NULL;
+
+    c = s->ssh.session->current_crypto;
+    assert_non_null(c);
+    assert_int_equal(c->in_cipher->max_blocks,
+                     bytes / c->in_cipher->blocksize);
+    assert_int_equal(c->out_cipher->max_blocks,
+                     bytes / c->out_cipher->blocksize);
+    /* when strict kex is used, the newkeys reset the sequence number */
+    if ((s->ssh.session->flags & SSH_SESSION_FLAG_KEX_STRICT) != 0) {
+        assert_int_equal(c->out_cipher->packets, s->ssh.session->send_seq);
+        assert_int_equal(c->in_cipher->packets, s->ssh.session->recv_seq);
+    } else {
+        /* Otherwise we have less encrypted packets than transferred
+         * (first are not encrypted) */
+        assert_true(c->out_cipher->packets < s->ssh.session->send_seq);
+        assert_true(c->in_cipher->packets < s->ssh.session->recv_seq);
+    }
+}
+
 /* We lower the rekey limits manually and check that the rekey
  * really happens when sending data
  */
@@ -164,16 +189,10 @@ static void torture_rekey_send(void **state)
     rc = ssh_connect(s->ssh.session);
     assert_ssh_return_code(s->ssh.session, rc);
 
-    /* The blocks limit is set correctly */
-    c = s->ssh.session->current_crypto;
-    assert_int_equal(c->in_cipher->max_blocks,
-                     bytes / c->in_cipher->blocksize);
-    assert_int_equal(c->out_cipher->max_blocks,
-                     bytes / c->out_cipher->blocksize);
-    /* We should have less encrypted packets than transfered (first are not encrypted) */
-    assert_true(c->out_cipher->packets < s->ssh.session->send_seq);
-    assert_true(c->in_cipher->packets < s->ssh.session->recv_seq);
+    sanity_check_session(state);
     /* Copy the initial secret hash = session_id so we know we changed keys later */
+    c = s->ssh.session->current_crypto;
+    assert_non_null(c);
     secret_hash = malloc(c->digest_len);
     assert_non_null(secret_hash);
     memcpy(secret_hash, c->secret_hash, c->digest_len);
@@ -190,10 +209,11 @@ static void torture_rekey_send(void **state)
     rc = ssh_userauth_publickey_auto(s->ssh.session, NULL, NULL);
     assert_int_equal(rc, SSH_AUTH_SUCCESS);
 
-    /* send ignore packets of up to 1KB to trigger rekey */
+    /* send ignore packets of up to 1KB to trigger rekey. Send little bit more
+     * to make sure it completes with all different ciphers */
     memset(data, 0, sizeof(data));
     memset(data, 'A', 128);
-    for (i = 0; i < 16; i++) {
+    for (i = 0; i < KEX_RETRY; i++) {
         ssh_send_ignore(s->ssh.session, data);
         ssh_handle_packets(s->ssh.session, 50);
     }
@@ -269,14 +289,10 @@ static void torture_rekey_recv(void **state)
     sftp_file file;
     mode_t mask;
 
-    /* The blocks limit is set correctly */
-    c = s->ssh.session->current_crypto;
-    assert_int_equal(c->in_cipher->max_blocks, bytes / c->in_cipher->blocksize);
-    assert_int_equal(c->out_cipher->max_blocks, bytes / c->out_cipher->blocksize);
-    /* We should have less encrypted packets than transfered (first are not encrypted) */
-    assert_true(c->out_cipher->packets < s->ssh.session->send_seq);
-    assert_true(c->in_cipher->packets < s->ssh.session->recv_seq);
+    sanity_check_session(state);
     /* Copy the initial secret hash = session_id so we know we changed keys later */
+    c = s->ssh.session->current_crypto;
+    assert_non_null(c);
     secret_hash = malloc(c->digest_len);
     assert_non_null(secret_hash);
     memcpy(secret_hash, c->secret_hash, c->digest_len);
@@ -461,15 +477,10 @@ static void torture_rekey_different_kex(void **state)
     assert_ssh_return_code(s->ssh.session, rc);
 
     /* The blocks limit is set correctly */
-    c = s->ssh.session->current_crypto;
-    assert_int_equal(c->in_cipher->max_blocks,
-                     bytes / c->in_cipher->blocksize);
-    assert_int_equal(c->out_cipher->max_blocks,
-                     bytes / c->out_cipher->blocksize);
-    /* We should have less encrypted packets than transfered (first are not encrypted) */
-    assert_true(c->out_cipher->packets < s->ssh.session->send_seq);
-    assert_true(c->in_cipher->packets < s->ssh.session->recv_seq);
+    sanity_check_session(state);
     /* Copy the initial secret hash = session_id so we know we changed keys later */
+    c = s->ssh.session->current_crypto;
+    assert_non_null(c);
     secret_hash = malloc(c->digest_len);
     assert_non_null(secret_hash);
     memcpy(secret_hash, c->secret_hash, c->digest_len);
@@ -496,9 +507,15 @@ static void torture_rekey_different_kex(void **state)
      * to make sure the rekey it completes with all different ciphers (paddings */
     memset(data, 0, sizeof(data));
     memset(data, 'A', 128);
-    for (i = 0; i < 20; i++) {
+    for (i = 0; i < KEX_RETRY; i++) {
         ssh_send_ignore(s->ssh.session, data);
-        ssh_handle_packets(s->ssh.session, 50);
+        ssh_handle_packets(s->ssh.session, 100);
+
+        c = s->ssh.session->current_crypto;
+        /* SHA256 len */
+        if (c->digest_len != 32) {
+            break;
+        }
     }
 
     /* The rekey limit was restored in the new crypto to the same value */
@@ -568,9 +585,15 @@ static void torture_rekey_server_different_kex(void **state)
      * to make sure the rekey it completes with all different ciphers (paddings */
     memset(data, 0, sizeof(data));
     memset(data, 'A', 128);
-    for (i = 0; i < 25; i++) {
+    for (i = 0; i < KEX_RETRY; i++) {
         ssh_send_ignore(s->ssh.session, data);
-        ssh_handle_packets(s->ssh.session, 50);
+        ssh_handle_packets(s->ssh.session, 100);
+
+        c = s->ssh.session->current_crypto;
+        /* SHA256 len */
+        if (c->digest_len != 32) {
+            break;
+        }
     }
 
     /* Check that the secret hash is different than initially */
@@ -651,6 +674,92 @@ static void torture_rekey_server_recv(void **state)
 #endif /* WITH_SFTP */
 
 
+static void setup_server_for_good_guess(void *state)
+{
+    const char *default_sshd_config = "KexAlgorithms curve25519-sha256";
+    const char *fips_sshd_config = "KexAlgorithms ecdh-sha2-nistp256";
+    const char *sshd_config = default_sshd_config;
+
+    if (ssh_fips_mode()) {
+        sshd_config = fips_sshd_config;
+    }
+    /* This sets an only supported kex algorithm that we do not have as a first
+    * option */
+    torture_update_sshd_config(state, sshd_config);
+}
+
+static void torture_rekey_guess_send(void **state)
+{
+    struct torture_state *s = *state;
+
+    setup_server_for_good_guess(state);
+
+    /* Make the client send the first_kex_packet_follows flag during key
+     * exchange as well as during the rekey */
+    s->ssh.session->send_first_kex_follows = true;
+
+    torture_rekey_send(state);
+}
+
+static void torture_rekey_guess_wrong_send(void **state)
+{
+    struct torture_state *s = *state;
+    const char *sshd_config = "KexAlgorithms diffie-hellman-group14-sha256";
+
+    /* This sets an only supported kex algorithm that we do not have as a first
+     * option */
+    torture_update_sshd_config(state, sshd_config);
+
+    /* Make the client send the first_kex_packet_follows flag during key
+     * exchange as well as during the rekey */
+    s->ssh.session->send_first_kex_follows = true;
+
+    torture_rekey_send(state);
+}
+
+#ifdef WITH_SFTP
+static void torture_rekey_guess_recv(void **state)
+{
+    struct torture_state *s = *state;
+    int rc;
+
+    setup_server_for_good_guess(state);
+
+    /* Make the client send the first_kex_packet_follows flag during key
+     * exchange as well as during the rekey */
+    s->ssh.session->send_first_kex_follows = true;
+
+    rc = ssh_options_set(s->ssh.session, SSH_OPTIONS_REKEY_DATA, &bytes);
+    assert_ssh_return_code(s->ssh.session, rc);
+
+    session_setup_sftp(state);
+
+    torture_rekey_recv(state);
+}
+
+static void torture_rekey_guess_wrong_recv(void **state)
+{
+    struct torture_state *s = *state;
+    const char *sshd_config = "KexAlgorithms diffie-hellman-group14-sha256";
+    int rc;
+
+    /* This sets an only supported kex algorithm that we do not have as a first
+     * option */
+    torture_update_sshd_config(state, sshd_config);
+
+    /* Make the client send the first_kex_packet_follows flag during key
+     * exchange as well as during the rekey */
+    s->ssh.session->send_first_kex_follows = true;
+
+    rc = ssh_options_set(s->ssh.session, SSH_OPTIONS_REKEY_DATA, &bytes);
+    assert_ssh_return_code(s->ssh.session, rc);
+
+    session_setup_sftp(state);
+
+    torture_rekey_recv(state);
+}
+#endif /* WITH_SFTP */
+
 int torture_run_tests(void) {
     int rc;
     struct CMUnitTest tests[] = {
@@ -671,19 +780,34 @@ int torture_run_tests(void) {
         cmocka_unit_test_setup_teardown(torture_rekey_different_kex,
                                         session_setup,
                                         session_teardown),
-        /* Note, that this modifies the sshd_config */
+        /* TODO verify the two rekey are possible and the states are not broken after rekey */
+
+        cmocka_unit_test_setup_teardown(torture_rekey_server_different_kex,
+                                        session_setup,
+                                        session_teardown),
+        /* Note, that these tests modify the sshd_config so follow-up tests
+         * might get unexpected behavior if they do not update the server with
+         * torture_update_sshd_config() too */
         cmocka_unit_test_setup_teardown(torture_rekey_server_send,
                                         session_setup,
                                         session_teardown),
+        cmocka_unit_test_setup_teardown(torture_rekey_guess_send,
+                                        session_setup,
+                                        session_teardown),
+        cmocka_unit_test_setup_teardown(torture_rekey_guess_wrong_send,
+                                        session_setup,
+                                        session_teardown),
 #ifdef WITH_SFTP
         cmocka_unit_test_setup_teardown(torture_rekey_server_recv,
                                         session_setup_sftp_server,
                                         session_teardown),
-#endif /* WITH_SFTP */
-        cmocka_unit_test_setup_teardown(torture_rekey_server_different_kex,
+        cmocka_unit_test_setup_teardown(torture_rekey_guess_recv,
                                         session_setup,
                                         session_teardown),
-        /* TODO verify the two rekey are possible and the states are not broken after rekey */
+        cmocka_unit_test_setup_teardown(torture_rekey_guess_wrong_recv,
+                                        session_setup,
+                                        session_teardown),
+#endif /* WITH_SFTP */
     };
 
     ssh_init();

tests/client/torture_session.c

@@ -118,12 +118,47 @@ static void torture_channel_read_error(void **state) {
     ssh_channel_free(channel);
 }
 
+static void torture_pubkey_hash(void **state)
+{
+    struct torture_state *s = *state;
+    ssh_session session = s->ssh.session;
+    char *hash = NULL;
+    char *hexa = NULL;
+    int rc = 0;
+
+    /* bad arguments */
+    rc = ssh_get_pubkey_hash(session, NULL);
+    assert_int_equal(rc, SSH_ERROR);
+
+    rc = ssh_get_pubkey_hash(NULL, (unsigned char **)&hash);
+    assert_int_equal(rc, SSH_ERROR);
+
+    /* deprecated, but should be covered by tests! */
+    rc = ssh_get_pubkey_hash(session, (unsigned char **)&hash);
+    if (ssh_fips_mode()) {
+        /* When in FIPS mode, expect the call to fail */
+        assert_int_equal(rc, SSH_ERROR);
+    } else {
+        assert_int_equal(rc, MD5_DIGEST_LEN);
+
+        hexa = ssh_get_hexa((unsigned char *)hash, rc);
+        SSH_STRING_FREE_CHAR(hash);
+        assert_string_equal(hexa,
+                            "ee:80:7f:61:f9:d5:be:f1:96:86:cc:96:7a:db:7a:7b");
+
+        SSH_STRING_FREE_CHAR(hexa);
+    }
+}
+
 int torture_run_tests(void) {
     int rc;
     struct CMUnitTest tests[] = {
         cmocka_unit_test_setup_teardown(torture_channel_read_error,
                                         session_setup,
                                         session_teardown),
+        cmocka_unit_test_setup_teardown(torture_pubkey_hash,
+                                        session_setup,
+                                        session_teardown),
     };
 
     ssh_init();

tests/keys/certauth/id_rsa

@@ -1,27 +1,27 @@
------BEGIN RSA PRIVATE KEY-----
-MIIEiwIBAAKB/QMTSsCQqarOIauonYgjAt8E+lgSWBU/43ITyDDzLM4IS4wCcqXB
-1Fagz386FU1B2AcUqlPZ1+7RlaXkqgKr4nGHv00U/GG+YAUgUAw1G12kI4cvrnWr
-FIXwcq+VTJNej5pHxEqcRLw7ZBorpqm2UsY5KLr5R3uMNap7koj1Hbt9lKsvfDn6
-HjM4qY0ygx8hxf/4wCzIh5V4k9/UAMkqI2CM9c3yEE2aWh/4MDOnAFj+0T2sMAo8
-jyOZ6v+W7hmEtsUc9mEv+5B+hhVeYO/RwxketJAQRPYDSPSi1mjtv9fnzGk15q/l
-Hb2V/HP/pyIpao19A4daR0a4ia9Hk4UCAwEAAQKB/QKEaPxjrKzlWoQSWRdUaQY5
-Idyy7yw9hiMa9BK1COh/u66XVlY86Fwb9puR5Fu/WF67WIuX1PpizJXkLBBRtuDs
-lvY2BjrPQ/MONtc3JPYp4vbFXYxtAzh6zrTPhMVfcjV7Jr1XWZ+lEVOmhR2G4gvk
-P2WDozIKWub3jMLTt4afgHCGaKfKEUpKjFkiAalz8oLVv8qV1FVPPDT2PWeKMuE3
-XfoN7YUaP6+aPlNnjIv/3BDsrPsiKZ+AKXcERdPvVQa/LypzW08cqC6sIJKWVmQI
-3KgoYs9VvbDXfQ8jKfcsTApZkSDaLX6tf3Ei+76R0lbV4L1rpypa25qj9YECfwHP
-N+v/6yObJFL5/1rEuT7CFbfP8g5J8qUVufcPRKv//ChluLuWNxgLJmIv2ZffWwhe
-GKHlT98QPgFvsMSOyLeut4beZYKDSeVNvEt9eCBjOax2jOBGo3hv8j/Fs8yAfZOV
-Ardv2qUszubM+DVwjJzb3vaZyEesRucJISqkJeUCfwGzGdMp0LXrZ7aaQGgHj/P2
-DKGq0E2gnj/EBapatjxKm4hMRn/vkTWjCDCryTnvJqkW/00tr4GqWXoeilBFD270
-RcvbOe9LQmGlHIYzgwc5nfLDBQyeNnHRmkeD9LQRUfdTdHj4jf+35pHlsVUT0Rnl
-IMNoRA6V07bySFdI3SECfiF+1rbrxuhaCRIA0Ax3pL0eGuuTgksAm8VlbCMTgSiC
-kF1CrXXgSAHOZb02C9Bf4cwEFfjh/KxM/4eXDa+Rfg7JQJxmVLivqEAlxIOvIxBp
-xDnSWAljmrrllozyQnBsJDbbOm6BLf5+e5wIuryHvnP7vHNEU0J24g/78PxrrQJ/
-AVD4OzYzUfESzbUBFJBmyIZSmhJ0aOpwJOpniNvgLymI8zI/l22uhF/TQ/6HRbsV
-sfcBmoA7YKzRx2ZHsIsLvN6p/4u1fsJGkuERCk5yt/HDhfPLwU321IeEeMaVia+w
-T1/u4JF/SADhLTU69az3UJrHmQ7zRmh7I0DZDeB8gQJ+XqIqutPeerNtbqMjXGW8
-TdpqZAzAQAv6dPgaH0W0OzJe2hP9uy0D84H5f8Im/irJh/AXo/QL3obXqopyeLf0
-HfcUUnEZEBPlqsirZFtPClD+HL6Orf1je0oVV/aQssPkQl6/aXBNd+kS27U3NBML
-LmRhC4+Q+/M5MlRggLtn
------END RSA PRIVATE KEY-----
+-----BEGIN OPENSSH PRIVATE KEY-----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+-----END OPENSSH PRIVATE KEY-----

tests/keys/certauth/id_rsa-cert.pub

@@ -1 +1 @@
-ssh-rsa-cert-v01@openssh.com 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  libssh_torture_auth
+ssh-rsa-cert-v01@openssh.com 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 libssh_torture_auth

tests/keys/certauth/id_rsa.pub

@@ -1 +1 @@
-ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAA/QMTSsCQqarOIauonYgjAt8E+lgSWBU/43ITyDDzLM4IS4wCcqXB1Fagz386FU1B2AcUqlPZ1+7RlaXkqgKr4nGHv00U/GG+YAUgUAw1G12kI4cvrnWrFIXwcq+VTJNej5pHxEqcRLw7ZBorpqm2UsY5KLr5R3uMNap7koj1Hbt9lKsvfDn6HjM4qY0ygx8hxf/4wCzIh5V4k9/UAMkqI2CM9c3yEE2aWh/4MDOnAFj+0T2sMAo8jyOZ6v+W7hmEtsUc9mEv+5B+hhVeYO/RwxketJAQRPYDSPSi1mjtv9fnzGk15q/lHb2V/HP/pyIpao19A4daR0a4ia9Hk4U= libssh_torture_auth
+ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDQN6GtT+iGiKYwqiMVd2jW4QByrHh9LzsCMNTPy3izjfqmk/7T5Tf6quE4IT+Zdm9d7CNMeW2YS0Ic1JuxaFhOPCsRBQNE05VqGfY8RBNxf/2K2+y/09fv0iZu9mwtHR/UWyaiuRamcNCa6BruFgEUGPixX5UwvmJ6grY6tpQSrjoguzGpGBRN62QSuXNftLZI8Tu80zRqGYD4c0G4o1QP4E60LOSo3nh+UYD1NnuRqkLvGqJEcr5nNqFDY8VHgHFtU/W5MOxqduMo6kELiEhJqjeGLiJSfKPSAnyK2aSFBL6gj/YpZIZbTX+T1buM5RcNK3ssZRNJbqwgtgfOZ58L libssh_torture_auth

tests/pkd/pkd_keyutil.c

@@ -22,7 +22,7 @@
 #include "pkd_keyutil.h"
 #include "pkd_util.h"
 
-void setup_rsa_key() {
+void setup_rsa_key(void) {
     int rc = 0;
     if (access(LIBSSH_RSA_TESTKEY, F_OK) != 0) {
         rc = system_checked(OPENSSH_KEYGEN " -t rsa -q -N \"\" -f "
@@ -31,7 +31,7 @@ void setup_rsa_key() {
     assert_int_equal(rc, 0);
 }
 
-void setup_ed25519_key() {
+void setup_ed25519_key(void) {
     int rc = 0;
     if (access(LIBSSH_ED25519_TESTKEY, F_OK) != 0) {
         rc = system_checked(OPENSSH_KEYGEN " -t ed25519 -q -N \"\" -f "
@@ -41,7 +41,7 @@ void setup_ed25519_key() {
 }
 
 #ifdef HAVE_DSA
-void setup_dsa_key() {
+void setup_dsa_key(void) {
     int rc = 0;
     if (access(LIBSSH_DSA_TESTKEY, F_OK) != 0) {
         rc = system_checked(OPENSSH_KEYGEN " -t dsa -q -N \"\" -f "
@@ -51,7 +51,7 @@ void setup_dsa_key() {
 }
 #endif
 
-void setup_ecdsa_keys() {
+void setup_ecdsa_keys(void) {
     int rc = 0;
 
     if (access(LIBSSH_ECDSA_256_TESTKEY, F_OK) != 0) {
@@ -71,27 +71,27 @@ void setup_ecdsa_keys() {
     }
 }
 
-void cleanup_rsa_key() {
+void cleanup_rsa_key(void) {
     cleanup_key(LIBSSH_RSA_TESTKEY);
 }
 
-void cleanup_ed25519_key() {
+void cleanup_ed25519_key(void) {
     cleanup_key(LIBSSH_ED25519_TESTKEY);
 }
 
 #ifdef HAVE_DSA
-void cleanup_dsa_key() {
+void cleanup_dsa_key(void) {
     cleanup_key(LIBSSH_DSA_TESTKEY);
 }
 #endif
 
-void cleanup_ecdsa_keys() {
+void cleanup_ecdsa_keys(void) {
     cleanup_key(LIBSSH_ECDSA_256_TESTKEY);
     cleanup_key(LIBSSH_ECDSA_384_TESTKEY);
     cleanup_key(LIBSSH_ECDSA_521_TESTKEY);
 }
 
-void setup_openssh_client_keys() {
+void setup_openssh_client_keys(void) {
     int rc = 0;
 
     if (access(OPENSSH_CA_TESTKEY, F_OK) != 0) {
@@ -184,7 +184,7 @@ void setup_openssh_client_keys() {
     }
 }
 
-void cleanup_openssh_client_keys() {
+void cleanup_openssh_client_keys(void) {
     cleanup_key(OPENSSH_CA_TESTKEY);
     cleanup_key(OPENSSH_RSA_TESTKEY);
     cleanup_file(OPENSSH_RSA_TESTKEY "-sha256-cert.pub");
@@ -199,7 +199,7 @@ void cleanup_openssh_client_keys() {
     }
 }
 
-void setup_dropbear_client_rsa_key() {
+void setup_dropbear_client_rsa_key(void) {
     int rc = 0;
     if (access(DROPBEAR_RSA_TESTKEY, F_OK) != 0) {
         rc = system_checked(DROPBEAR_KEYGEN " -t rsa -f "
@@ -208,6 +208,6 @@ void setup_dropbear_client_rsa_key() {
     assert_int_equal(rc, 0);
 }
 
-void cleanup_dropbear_client_rsa_key() {
+void cleanup_dropbear_client_rsa_key(void) {
     unlink(DROPBEAR_RSA_TESTKEY);
 }

tests/server/torture_server_config.c

@@ -285,9 +285,7 @@ static int stop_server(void **state)
     assert_non_null(s);
 
     rc = torture_terminate_process(s->srv_pidfile);
-    if (rc != 0) {
-        fprintf(stderr, "XXXXXX Failed to terminate sshd\n");
-    }
+    assert_return_code(rc, errno);
 
     unlink(s->srv_pidfile);
 
@@ -513,6 +511,12 @@ static void torture_server_config_ciphers(void **state)
         /* Try each algorithm individually */
         j = 0;
         while(tokens->tokens[j] != NULL) {
+            char *cmp = strstr(OPENSSH_CIPHERS, tokens->tokens[j]);
+            if (cmp == NULL) {
+                /* This cipher is not supported by the OpenSSH. Skip it */
+                j++;
+                continue;
+            }
             snprintf(config_content,
                     sizeof(config_content),
                     "HostKey %s\nCiphers %s\n",

tests/torture.c

@@ -250,8 +250,12 @@ int torture_terminate_process(const char *pidfile)
 
         rc = kill(pid, 0);
         if (rc != 0) {
-            is_running = 0;
-            break;
+            /* Process not found */
+            if (errno == ESRCH) {
+                is_running = 0;
+                rc = 0;
+                break;
+            }
         }
     }
 
@@ -260,7 +264,7 @@ int torture_terminate_process(const char *pidfile)
                 "WARNING: The process with pid %u is still running!\n", pid);
     }
 
-    return 0;
+    return rc;
 }
 
 ssh_session torture_ssh_session(struct torture_state *s,
@@ -856,21 +860,16 @@ static int torture_wait_for_daemon(unsigned int seconds)
     return 1;
 }
 
-void torture_setup_sshd_server(void **state, bool pam)
+static int torture_start_sshd_server(void **state)
 {
-    struct torture_state *s;
+    struct torture_state *s = *state;
     char sshd_start_cmd[1024];
     int rc;
 
-    torture_setup_socket_dir(state);
-    torture_setup_create_sshd_config(state, pam);
-
     /* Set the default interface for the server */
     setenv("SOCKET_WRAPPER_DEFAULT_IFACE", "10", 1);
     setenv("PAM_WRAPPER", "1", 1);
 
-    s = *state;
-
     snprintf(sshd_start_cmd, sizeof(sshd_start_cmd),
              SSHD_EXECUTABLE " -r -f %s -E %s/sshd/daemon.log 2> %s/sshd/cwrap.log",
              s->srv_config, s->socket_dir, s->socket_dir);
@@ -882,7 +881,20 @@ void torture_setup_sshd_server(void **state, bool pam)
     unsetenv("PAM_WRAPPER");
 
     /* Wait until the sshd is ready to accept connections */
-    rc = torture_wait_for_daemon(5);
+    rc = torture_wait_for_daemon(15);
+    assert_int_equal(rc, 0);
+
+    return SSH_OK;
+}
+
+void torture_setup_sshd_server(void **state, bool pam)
+{
+    int rc;
+
+    torture_setup_socket_dir(state);
+    torture_setup_create_sshd_config(state, pam);
+
+    rc = torture_start_sshd_server(state);
     assert_int_equal(rc, 0);
 }
 
@@ -922,29 +934,12 @@ static int
 torture_reload_sshd_server(void **state)
 {
     struct torture_state *s = *state;
-    pid_t pid;
     int rc;
 
-    /* read the pidfile */
-    pid = torture_read_pidfile(s->srv_pidfile);
-    assert_int_not_equal(pid, -1);
+    rc = torture_terminate_process(s->srv_pidfile);
+    assert_return_code(rc, errno);
 
-    kill(pid, SIGHUP);
-
-    /* 10 ms */
-    usleep(10 * 1000);
-
-    rc = kill(pid, 0);
-    if (rc != 0) {
-        fprintf(stderr,
-                "ERROR: SSHD process %u died during reload!\n", pid);
-        return SSH_ERROR;
-    }
-
-    /* Wait until the sshd is ready to accept connections */
-    rc = torture_wait_for_daemon(5);
-    assert_int_equal(rc, 0);
-    return SSH_OK;
+    return torture_start_sshd_server(state);
 }
 
 /* @brief: Updates SSHD server configuration with more options and
@@ -980,9 +975,7 @@ void torture_teardown_sshd_server(void **state)
     int rc;
 
     rc = torture_terminate_process(s->srv_pidfile);
-    if (rc != 0) {
-        fprintf(stderr, "XXXXXX Failed to terminate sshd\n");
-    }
+    assert_return_code(rc, errno);
 
     torture_teardown_socket_dir(state);
 }

tests/unittests/torture_config.c

@@ -671,6 +671,32 @@ static void torture_config_proxyjump(void **state) {
     assert_string_equal(session->opts.ProxyCommand,
                         "ssh -W [%h]:%p 2620:52:0::fed");
 
+    /* Multiple @ is allowed in second jump */
+    torture_write_file(LIBSSH_TESTCONFIG11,
+                       "Host allowed-hostname\n"
+                       "\tProxyJump localhost,user@principal.com@jumpbox:22\n"
+                       "");
+    torture_reset_config(session);
+    ssh_options_set(session, SSH_OPTIONS_HOST, "allowed-hostname");
+    ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
+    assert_ssh_return_code(session, ret);
+    assert_string_equal(session->opts.ProxyCommand,
+                        "ssh -J user@principal.com@jumpbox:22 -W [%h]:%p localhost");
+
+    /* Multiple @ is allowed */
+    torture_write_file(LIBSSH_TESTCONFIG11,
+                       "Host allowed-hostname\n"
+                       "\tProxyJump user@principal.com@jumpbox:22\n"
+                       "");
+    torture_reset_config(session);
+    ssh_options_set(session, SSH_OPTIONS_HOST, "allowed-hostname");
+    ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
+    assert_ssh_return_code(session, ret);
+    assert_string_equal(session->opts.ProxyCommand,
+                        "ssh -l user@principal.com -p 22 -W [%h]:%p jumpbox");
+
+    /* In this part, we try various other config files and strings. */
+
     /* Try to create some invalid configurations */
     /* Non-numeric port */
     torture_write_file(LIBSSH_TESTCONFIG11,
@@ -682,16 +708,6 @@ static void torture_config_proxyjump(void **state) {
     ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
     assert_ssh_return_code_equal(session, ret, SSH_ERROR);
 
-    /* Too many @ */
-    torture_write_file(LIBSSH_TESTCONFIG11,
-                       "Host bad-hostname\n"
-                       "\tProxyJump user@principal.com@jumpbox:22\n"
-                       "");
-    torture_reset_config(session);
-    ssh_options_set(session, SSH_OPTIONS_HOST, "bad-hostname");
-    ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
-    assert_ssh_return_code_equal(session, ret, SSH_ERROR);
-
     /* Braces mismatch in hostname */
     torture_write_file(LIBSSH_TESTCONFIG11,
                        "Host mismatch\n"
@@ -752,16 +768,6 @@ static void torture_config_proxyjump(void **state) {
     ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
     assert_ssh_return_code_equal(session, ret, SSH_ERROR);
 
-    /* Too many @ in second jump */
-    torture_write_file(LIBSSH_TESTCONFIG11,
-                       "Host bad-hostname\n"
-                       "\tProxyJump localhost,user@principal.com@jumpbox:22\n"
-                       "");
-    torture_reset_config(session);
-    ssh_options_set(session, SSH_OPTIONS_HOST, "bad-hostname");
-    ret = ssh_config_parse_file(session, LIBSSH_TESTCONFIG11);
-    assert_ssh_return_code_equal(session, ret, SSH_ERROR);
-
     /* Braces mismatch in second jump */
     torture_write_file(LIBSSH_TESTCONFIG11,
                        "Host mismatch\n"

tests/unittests/torture_misc.c

@@ -17,7 +17,14 @@
 #include "misc.c"
 #include "error.c"
 
+#ifdef _WIN32
+#include <netioapi.h>
+#else
+#include <net/if.h>
+#endif
+
 #define TORTURE_TEST_DIR "/usr/local/bin/truc/much/.."
+#define TORTURE_IPV6_LOCAL_LINK "fe80::98e1:82ff:fe8d:28b3%%%s"
 
 const char template[] = "temp_dir_XXXXXX";
 
@@ -656,6 +663,116 @@ static void torture_ssh_newline_vis(UNUSED_PARAM(void **state))
     assert_string_equal(buffer, "a\\nb\\n");
 }
 
+static void torture_ssh_check_hostname_syntax(void **state)
+{
+    int rc;
+    (void)state;
+
+    rc = ssh_check_hostname_syntax("duckduckgo.com");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("www.libssh.org");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("Some-Thing.com");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("amazon.a23456789012345678901234567890123456789012345678901234567890123");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("amazon.a23456789012345678901234567890123456789012345678901234567890123.a23456789012345678901234567890123456789012345678901234567890123.ok");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("amazon.a23456789012345678901234567890123456789012345678901234567890123.a23456789012345678901234567890123456789012345678901234567890123.a23456789012345678901234567890123456789012345678901234567890123");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("lavabo-inter.innocentes-manus-meas");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("localhost");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("a");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("a-0.b-b");
+    assert_int_equal(rc, SSH_OK);
+    rc = ssh_check_hostname_syntax("libssh.");
+    assert_int_equal(rc, SSH_OK);
+
+    rc = ssh_check_hostname_syntax(NULL);
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("/");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("@");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("[");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("`");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("{");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("&");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("|");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("\"");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("`");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax(" ");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("*the+giant&\"rooks\".c0m");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("!www.libssh.org");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("--.--");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("libssh.a234567890123456789012345678901234567890123456789012345678901234");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("libssh.a234567890123456789012345678901234567890123456789012345678901234.a234567890123456789012345678901234567890123456789012345678901234");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("libssh-");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("fe80::9656:d028:8652:66b6");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax(".");
+    assert_int_equal(rc, SSH_ERROR);
+    rc = ssh_check_hostname_syntax("..");
+    assert_int_equal(rc, SSH_ERROR);
+}
+
+static void torture_ssh_is_ipaddr(void **state) {
+    int rc;
+    char *interf = malloc(64);
+    char *test_interf = malloc(128);
+    (void)state;
+
+    assert_non_null(interf);
+    assert_non_null(test_interf);
+    rc = ssh_is_ipaddr("201.255.3.69");
+    assert_int_equal(rc, 1);
+    rc = ssh_is_ipaddr("::1");
+    assert_int_equal(rc, 1);
+    rc = ssh_is_ipaddr("2001:0db8:85a3:0000:0000:8a2e:0370:7334");
+    assert_int_equal(rc, 1);
+    if_indextoname(1, interf);
+    assert_non_null(interf);
+    rc = sprintf(test_interf, TORTURE_IPV6_LOCAL_LINK, interf);
+    /* the "%%s" is not written */
+    assert_int_equal(rc, strlen(interf) + strlen(TORTURE_IPV6_LOCAL_LINK) - 3);
+    rc = ssh_is_ipaddr(test_interf);
+    assert_int_equal(rc, 1);
+    free(interf);
+    free(test_interf);
+
+    rc = ssh_is_ipaddr("..");
+    assert_int_equal(rc, 0);
+    rc = ssh_is_ipaddr(":::");
+    assert_int_equal(rc, 0);
+    rc = ssh_is_ipaddr("1.1.1.1.1");
+    assert_int_equal(rc, 0);
+    rc = ssh_is_ipaddr("1.1");
+    assert_int_equal(rc, 0);
+    rc = ssh_is_ipaddr("caesar");
+    assert_int_equal(rc, 0);
+    rc = ssh_is_ipaddr("::xa:1");
+    assert_int_equal(rc, 0);
+}
+
 int torture_run_tests(void) {
     int rc;
     struct CMUnitTest tests[] = {
@@ -678,6 +795,8 @@ int torture_run_tests(void) {
         cmocka_unit_test(torture_ssh_newline_vis),
         cmocka_unit_test(torture_ssh_mkdirs),
         cmocka_unit_test(torture_ssh_quote_file_name),
+        cmocka_unit_test(torture_ssh_check_hostname_syntax),
+        cmocka_unit_test(torture_ssh_is_ipaddr),
     };
 
     ssh_init();