New ssh_get_local_hostname()

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

include/libssh/misc.h

@@ -45,6 +45,7 @@ extern "C" {
 /* gets the user home dir. */
 char *ssh_get_user_home_dir(ssh_session session);
 char *ssh_get_local_username(void);
+char *ssh_get_local_hostname(void);
 int ssh_file_readaccess_ok(const char *file);
 int ssh_dir_writeable(const char *path);
 

src/gssapi.c

@@ -198,7 +198,7 @@ int
 ssh_gssapi_handle_userauth(ssh_session session, const char *user,
                            uint32_t n_oid, ssh_string *oids)
 {
-    char hostname[NI_MAXHOST] = {0};
+    char *hostname = NULL;
     OM_uint32 maj_stat, min_stat;
     size_t i;
     gss_OID_set supported; /* oids supported by server */
@@ -210,14 +210,6 @@ ssh_gssapi_handle_userauth(ssh_session session, const char *user,
     int rc;
     char err_msg[SSH_ERRNO_MSG_MAX] = {0};
 
-    rc = gethostname(hostname, 64);
-    if (rc != 0) {
-        SSH_LOG(SSH_LOG_TRACE,
-                "Error getting hostname: %s",
-                ssh_strerror(errno, err_msg, SSH_ERRNO_MSG_MAX));
-        return SSH_ERROR;
-    }
-
     /* Destroy earlier GSSAPI context if any */
     ssh_gssapi_free(session);
     rc = ssh_gssapi_init(session);
@@ -284,7 +276,16 @@ ssh_gssapi_handle_userauth(ssh_session session, const char *user,
         return SSH_OK;
     }
 
+    hostname = ssh_get_local_hostname();
+    if (hostname == NULL) {
+        SSH_LOG(SSH_LOG_TRACE,
+                "Error getting hostname: %s",
+                ssh_strerror(errno, err_msg, SSH_ERRNO_MSG_MAX));
+        return SSH_ERROR;
+    }
+
     rc = ssh_gssapi_import_name(session->gssapi, hostname);
+    SAFE_FREE(hostname);
     if (rc != SSH_OK) {
         ssh_auth_reply_default(session, 0);
         gss_release_oid_set(&min_stat, &both_supported);

src/kex-gss.c

@@ -421,7 +421,7 @@ int ssh_server_gss_kex_process_init(ssh_session session, ssh_buffer packet)
     gss_name_t client_name = GSS_C_NO_NAME;
     OM_uint32 ret_flags = 0;
     gss_buffer_desc mic = GSS_C_EMPTY_BUFFER, msg = GSS_C_EMPTY_BUFFER;
-    char hostname[NI_MAXHOST] = {0};
+    char *hostname = NULL;
     char err_msg[SSH_ERRNO_MSG_MAX] = {0};
 
     rc = ssh_buffer_unpack(packet, "S", &otoken);
@@ -538,8 +538,8 @@ int ssh_server_gss_kex_process_init(ssh_session session, ssh_buffer packet)
         goto error;
     }
 
-    rc = gethostname(hostname, 64);
+    hostname = ssh_get_local_hostname();
-    if (rc != 0) {
+    if (hostname == NULL) {
         SSH_LOG(SSH_LOG_TRACE,
                 "Error getting hostname: %s",
                 ssh_strerror(errno, err_msg, SSH_ERRNO_MSG_MAX));
@@ -547,6 +547,7 @@ int ssh_server_gss_kex_process_init(ssh_session session, ssh_buffer packet)
     }
 
     rc = ssh_gssapi_import_name(session->gssapi, hostname);
+    SAFE_FREE(hostname);
     if (rc != SSH_OK) {
         goto error;
     }

src/legacy.c

@@ -615,10 +615,10 @@ int ssh_publickey_to_file(ssh_session session,
     FILE *fp = NULL;
     char *user = NULL;
     char buffer[1024];
-    char host[256];
+    char *host = NULL;
     unsigned char *pubkey_64 = NULL;
     size_t len;
-    int rc;
+
     if(session==NULL)
         return SSH_ERROR;
     if(file==NULL || pubkey==NULL){
@@ -636,8 +636,8 @@ int ssh_publickey_to_file(ssh_session session,
         return SSH_ERROR;
     }
 
-    rc = gethostname(host, sizeof(host));
+    host = ssh_get_local_hostname();
-    if (rc < 0) {
+    if (host == NULL) {
         SAFE_FREE(user);
         SAFE_FREE(pubkey_64);
         return SSH_ERROR;
@@ -651,6 +651,7 @@ int ssh_publickey_to_file(ssh_session session,
 
     SAFE_FREE(pubkey_64);
     SAFE_FREE(user);
+    SAFE_FREE(host);
 
     SSH_LOG(SSH_LOG_RARE, "Trying to write public key file: %s", file);
     SSH_LOG(SSH_LOG_PACKET, "public key file content: %s", buffer);

src/misc.c

@@ -1233,6 +1233,18 @@ char *ssh_path_expand_tilde(const char *d)
     return r;
 }
 
+char *ssh_get_local_hostname(void)
+{
+    char host[NI_MAXHOST] = {0};
+    int rc;
+
+    rc = gethostname(host, sizeof(host));
+    if (rc != 0) {
+        return NULL;
+    }
+    return strdup(host);
+}
+
 /** @internal
  * @brief expands a string in function of session options
  * @param[in] s Format string to expand. Known parameters:
@@ -1249,7 +1261,6 @@ char *ssh_path_expand_tilde(const char *d)
  */
 char *ssh_path_expand_escape(ssh_session session, const char *s)
 {
-    char host[NI_MAXHOST] = {0};
     char *buf = NULL;
     char *r = NULL;
     char *x = NULL;
@@ -1313,9 +1324,7 @@ char *ssh_path_expand_escape(ssh_session session, const char *s)
             x = ssh_get_local_username();
             break;
         case 'l':
-            if (gethostname(host, sizeof(host) == 0)) {
+            x = ssh_get_local_hostname();
-                x = strdup(host);
-            }
             break;
         case 'h':
             if (session->opts.host) {

src/pki.c

@@ -2684,7 +2684,7 @@ int ssh_pki_export_pubkey_file(const ssh_key key,
                                const char *filename)
 {
     char key_buf[MAX_LINE_SIZE];
-    char host[256];
+    char *host = NULL;
     char *b64_key = NULL;
     char *user = NULL;
     FILE *fp = NULL;
@@ -2699,8 +2699,8 @@ int ssh_pki_export_pubkey_file(const ssh_key key,
         return SSH_ERROR;
     }
 
-    rc = gethostname(host, sizeof(host));
+    host = ssh_get_local_hostname();
-    if (rc < 0) {
+    if (host == NULL) {
         free(user);
         return SSH_ERROR;
     }
@@ -2708,6 +2708,7 @@ int ssh_pki_export_pubkey_file(const ssh_key key,
     rc = ssh_pki_export_pubkey_base64(key, &b64_key);
     if (rc < 0) {
         free(user);
+        free(host);
         return SSH_ERROR;
     }
 
@@ -2718,6 +2719,7 @@ int ssh_pki_export_pubkey_file(const ssh_key key,
                   user,
                   host);
     free(user);
+    free(host);
     free(b64_key);
     if (rc < 0) {
         return SSH_ERROR;