diff --git a/src/bind_config.c b/src/bind_config.c
index 14b84db0..ace5a0ac 100644
--- a/src/bind_config.c
+++ b/src/bind_config.c
@@ -40,7 +40,9 @@
 #include "libssh/server.h"
 #include "libssh/options.h"
 
+#ifndef MAX_LINE_SIZE
 #define MAX_LINE_SIZE 1024
+#endif
 
 /* Flags used for the parser state */
 #define PARSING     1
diff --git a/src/config.c b/src/config.c
index 599d6f80..a082e994 100644
--- a/src/config.c
+++ b/src/config.c
@@ -48,7 +48,9 @@
 #include "libssh/misc.h"
 #include "libssh/options.h"
 
+#ifndef MAX_LINE_SIZE
 #define MAX_LINE_SIZE 1024
+#endif
 
 struct ssh_config_keyword_table_s {
   const char *name;
diff --git a/src/known_hosts.c b/src/known_hosts.c
index ec6da308..3feab159 100644
--- a/src/known_hosts.c
+++ b/src/known_hosts.c
@@ -45,6 +45,10 @@
 # include <arpa/inet.h>
 #endif
 
+#ifndef MAX_LINE_SIZE
+#define MAX_LINE_SIZE 4096
+#endif
+
 /**
  * @addtogroup libssh_session
  *
@@ -74,7 +78,7 @@ static struct ssh_tokens_st *ssh_get_knownhost_line(FILE **file,
                                                     const char *filename,
                                                     const char **found_type)
 {
-    char buffer[4096] = {0};
+    char buffer[MAX_LINE_SIZE] = {0};
     char *ptr;
     struct ssh_tokens_st *tokens;
 
@@ -431,7 +435,6 @@ char * ssh_dump_knownhost(ssh_session session) {
     ssh_key server_pubkey = NULL;
     char *host;
     char *hostport;
-    size_t len = 4096;
     char *buffer;
     char *b64_key;
     int rc;
@@ -467,7 +470,7 @@ char * ssh_dump_knownhost(ssh_session session) {
         return NULL;
     }
 
-    buffer = calloc (1, 4096);
+    buffer = calloc (1, MAX_LINE_SIZE);
     if (!buffer) {
         SAFE_FREE(host);
         return NULL;
@@ -480,7 +483,7 @@ char * ssh_dump_knownhost(ssh_session session) {
         return NULL;
     }
 
-    snprintf(buffer, len,
+    snprintf(buffer, MAX_LINE_SIZE,
             "%s %s %s\n",
             host,
             server_pubkey->type_c,
diff --git a/src/knownhosts.c b/src/knownhosts.c
index f2ef088c..ad36363e 100644
--- a/src/knownhosts.c
+++ b/src/knownhosts.c
@@ -44,6 +44,10 @@
 #include "libssh/knownhosts.h"
 #include "libssh/token.h"
 
+#ifndef MAX_LINE_SIZE
+#define MAX_LINE_SIZE 8192
+#endif
+
 /**
  * @addtogroup libssh_session
  *
@@ -216,7 +220,7 @@ static int ssh_known_hosts_read_entries(const char *match,
                                         const char *filename,
                                         struct ssh_list **entries)
 {
-    char line[8192];
+    char line[MAX_LINE_SIZE];
     size_t lineno = 0;
     size_t len = 0;
     FILE *fp;
@@ -895,7 +899,7 @@ int ssh_session_export_known_hosts_entry(ssh_session session,
 {
     ssh_key server_pubkey = NULL;
     char *host = NULL;
-    char entry_buf[4096] = {0};
+    char entry_buf[MAX_LINE_SIZE] = {0};
     char *b64_key = NULL;
     int rc;
 
diff --git a/src/pki.c b/src/pki.c
index 9248c9b3..5d57ca71 100644
--- a/src/pki.c
+++ b/src/pki.c
@@ -67,6 +67,10 @@
 #include "libssh/misc.h"
 #include "libssh/agent.h"
 
+#ifndef MAX_LINE_SIZE
+#define MAX_LINE_SIZE 4096
+#endif
+
 #define PKCS11_URI "pkcs11:"
 
 enum ssh_keytypes_e pki_privatekey_type_from_string(const char *privkey)
@@ -2094,7 +2098,7 @@ int ssh_pki_export_pubkey_base64(const ssh_key key,
 int ssh_pki_export_pubkey_file(const ssh_key key,
                                const char *filename)
 {
-    char key_buf[4096];
+    char key_buf[MAX_LINE_SIZE];
     char host[256];
     char *b64_key;
     char *user;