dh: Add support for diffie-hellman-group14-sha1.

include/libssh/crypto.h

@@ -49,6 +49,8 @@
 enum ssh_key_exchange_e {
   /* diffie-hellman-group1-sha1 */
   SSH_KEX_DH_GROUP1_SHA1=1,
+  /* diffie-hellman-group14-sha1 */
+  SSH_KEX_DH_GROUP14_SHA1,
   /* ecdh-sha2-nistp256 */
   SSH_KEX_ECDH_SHA2_NISTP256
 };

src/client.c

@@ -194,6 +194,7 @@ static int dh_handshake(ssh_session session) {
     case DH_STATE_INIT:
       switch(session->next_crypto->kex_type){
         case SSH_KEX_DH_GROUP1_SHA1:
+        case SSH_KEX_DH_GROUP14_SHA1:
           rc = ssh_client_dh_init(session);
           break;
 #ifdef HAVE_ECDH

src/dh.c

@@ -5,6 +5,7 @@
  *
  * Copyright (c) 2003-2008 by Aris Adamantiadis
  * Copyright (c) 2009      by Andreas Schneider <mail@cynapses.org>
+ * Copyright (c) 2012      by Dmitriy Kuznetsov <dk@yandex.ru>
  *
  * The SSH Library is free software; you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published by
@@ -67,7 +68,7 @@
 #include <openssl/err.h>
 #endif
 
-static unsigned char p_value[] = {
+static unsigned char p_group1_value[] = {
         0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2,
         0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
         0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6,
@@ -79,13 +80,45 @@ static unsigned char p_value[] = {
         0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11,
         0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE6, 0x53, 0x81,
         0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
-#define P_LEN 128	/* Size in bytes of the p number */
+#define P_GROUP1_LEN 128	/* Size in bytes of the p number */
+
+
+static unsigned char p_group14_value[] = {
+        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xC9, 0x0F, 0xDA, 0xA2,
+        0x21, 0x68, 0xC2, 0x34, 0xC4, 0xC6, 0x62, 0x8B, 0x80, 0xDC, 0x1C, 0xD1,
+        0x29, 0x02, 0x4E, 0x08, 0x8A, 0x67, 0xCC, 0x74, 0x02, 0x0B, 0xBE, 0xA6,
+        0x3B, 0x13, 0x9B, 0x22, 0x51, 0x4A, 0x08, 0x79, 0x8E, 0x34, 0x04, 0xDD,
+        0xEF, 0x95, 0x19, 0xB3, 0xCD, 0x3A, 0x43, 0x1B, 0x30, 0x2B, 0x0A, 0x6D,
+        0xF2, 0x5F, 0x14, 0x37, 0x4F, 0xE1, 0x35, 0x6D, 0x6D, 0x51, 0xC2, 0x45,
+        0xE4, 0x85, 0xB5, 0x76, 0x62, 0x5E, 0x7E, 0xC6, 0xF4, 0x4C, 0x42, 0xE9,
+        0xA6, 0x37, 0xED, 0x6B, 0x0B, 0xFF, 0x5C, 0xB6, 0xF4, 0x06, 0xB7, 0xED,
+        0xEE, 0x38, 0x6B, 0xFB, 0x5A, 0x89, 0x9F, 0xA5, 0xAE, 0x9F, 0x24, 0x11,
+        0x7C, 0x4B, 0x1F, 0xE6, 0x49, 0x28, 0x66, 0x51, 0xEC, 0xE4, 0x5B, 0x3D,
+        0xC2, 0x00, 0x7C, 0xB8, 0xA1, 0x63, 0xBF, 0x05, 0x98, 0xDA, 0x48, 0x36,
+        0x1C, 0x55, 0xD3, 0x9A, 0x69, 0x16, 0x3F, 0xA8, 0xFD, 0x24, 0xCF, 0x5F,
+        0x83, 0x65, 0x5D, 0x23, 0xDC, 0xA3, 0xAD, 0x96, 0x1C, 0x62, 0xF3, 0x56,
+        0x20, 0x85, 0x52, 0xBB, 0x9E, 0xD5, 0x29, 0x07, 0x70, 0x96, 0x96, 0x6D,
+        0x67, 0x0C, 0x35, 0x4E, 0x4A, 0xBC, 0x98, 0x04, 0xF1, 0x74, 0x6C, 0x08,
+        0xCA, 0x18, 0x21, 0x7C, 0x32, 0x90, 0x5E, 0x46, 0x2E, 0x36, 0xCE, 0x3B,
+        0xE3, 0x9E, 0x77, 0x2C, 0x18, 0x0E, 0x86, 0x03, 0x9B, 0x27, 0x83, 0xA2,
+        0xEC, 0x07, 0xA2, 0x8F, 0xB5, 0xC5, 0x5D, 0xF0, 0x6F, 0x4C, 0x52, 0xC9,
+        0xDE, 0x2B, 0xCB, 0xF6, 0x95, 0x58, 0x17, 0x18, 0x39, 0x95, 0x49, 0x7C,
+        0xEA, 0x95, 0x6A, 0xE5, 0x15, 0xD2, 0x26, 0x18, 0x98, 0xFA, 0x05, 0x10,
+        0x15, 0x72, 0x8E, 0x5A, 0x8A, 0xAC, 0xAA, 0x68, 0xFF, 0xFF, 0xFF, 0xFF,
+        0xFF, 0xFF, 0xFF, 0xFF};
+
+#define P_GROUP14_LEN 256 /* Size in bytes of the p number for group 14 */
 
 static unsigned long g_int = 2 ;	/* G is defined as 2 by the ssh2 standards */
 static bignum g;
-static bignum p;
+static bignum p_group1;
+static bignum p_group14;
 static int ssh_crypto_initialized;
 
+static bignum select_p(enum ssh_key_exchange_e type) {
+    return type == SSH_KEX_DH_GROUP14_SHA1 ? p_group14 : p_group1;
+}
+
 int ssh_get_random(void *where, int len, int strong){
 
 #ifdef HAVE_LIBGCRYPT
@@ -107,6 +140,7 @@ int ssh_get_random(void *where, int len, int strong){
   return 1;
 }
 
+
 /*
  * This inits the values g and p which are used for DH key agreement
  * FIXME: Make the function thread safe by adding a semaphore or mutex.
@@ -128,20 +162,40 @@ int ssh_crypto_init(void) {
     bignum_set_word(g,g_int);
 
 #ifdef HAVE_LIBGCRYPT
-    bignum_bin2bn(p_value, P_LEN, &p);
+    bignum_bin2bn(p_group1_value, P_GROUP1_LEN, &p_group1);
-    if (p == NULL) {
+    if (p_group1 == NULL) {
       bignum_free(g);
       g = NULL;
       return -1;
     }
+    bignum_bin2bn(p_group14_value, P_GROUP14_LEN, &p_group14);
+    if (p_group1 == NULL) {
+      bignum_free(g);
+      bignum_free(p_group1);
+      g = NULL;
+      p_group1 = NULL;
+      return -1;
+    }
+
 #elif defined HAVE_LIBCRYPTO
-    p = bignum_new();
+    p_group1 = bignum_new();
-    if (p == NULL) {
+    if (p_group1 == NULL) {
       bignum_free(g);
       g = NULL;
       return -1;
     }
-    bignum_bin2bn(p_value, P_LEN, p);
+    bignum_bin2bn(p_group1_value, P_GROUP1_LEN, p_group1);
+
+    p_group14 = bignum_new();
+    if (p_group14 == NULL) {
+      bignum_free(g);
+      bignum_free(p_group1);
+      g = NULL;
+      p_group1 = NULL;
+      return -1;
+    }
+    bignum_bin2bn(p_group14_value, P_GROUP14_LEN, p_group14);
+
     OpenSSL_add_all_algorithms();
 
 #endif
@@ -156,8 +210,10 @@ void ssh_crypto_finalize(void) {
   if (ssh_crypto_initialized) {
     bignum_free(g);
     g = NULL;
-    bignum_free(p);
+    bignum_free(p_group1);
-    p = NULL;
+    p_group1 = NULL;
+    bignum_free(p_group14);
+    p_group14 = NULL;
 #ifdef HAVE_LIBGCRYPT
     gcry_control(GCRYCTL_TERM_SECMEM);
 #elif defined HAVE_LIBCRYPTO
@@ -295,9 +351,11 @@ int dh_generate_e(ssh_session session) {
   }
 
 #ifdef HAVE_LIBGCRYPT
-  bignum_mod_exp(session->next_crypto->e, g, session->next_crypto->x, p);
+  bignum_mod_exp(session->next_crypto->e, g, session->next_crypto->x,
+      select_p(type));
 #elif defined HAVE_LIBCRYPTO
-  bignum_mod_exp(session->next_crypto->e, g, session->next_crypto->x, p, ctx);
+  bignum_mod_exp(session->next_crypto->e, g, session->next_crypto->x,
+      select_p(session->next_crypto->kex_type), ctx);
 #endif
 
 #ifdef DEBUG_CRYPTO
@@ -328,9 +386,11 @@ int dh_generate_f(ssh_session session) {
   }
 
 #ifdef HAVE_LIBGCRYPT
-  bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y, p);
+  bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y,
+      select_p(session->next_crypto->kex_type));
 #elif defined HAVE_LIBCRYPTO
-  bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y, p, ctx);
+  bignum_mod_exp(session->next_crypto->f, g, session->next_crypto->y,
+      select_p(session->next_crypto->kex_type), ctx);
 #endif
 
 #ifdef DEBUG_CRYPTO
@@ -460,18 +520,18 @@ int dh_build_k(ssh_session session) {
 #ifdef HAVE_LIBGCRYPT
   if(session->client) {
     bignum_mod_exp(session->next_crypto->k, session->next_crypto->f,
-        session->next_crypto->x, p);
+        session->next_crypto->x, select_p(session->next_crypto->kex_type));
   } else {
     bignum_mod_exp(session->next_crypto->k, session->next_crypto->e,
-        session->next_crypto->y, p);
+        session->next_crypto->y, select_p(session->next_crypto->kex_type));
   }
 #elif defined HAVE_LIBCRYPTO
   if (session->client) {
     bignum_mod_exp(session->next_crypto->k, session->next_crypto->f,
-        session->next_crypto->x, p, ctx);
+        session->next_crypto->x, select_p(session->next_crypto->kex_type), ctx);
   } else {
     bignum_mod_exp(session->next_crypto->k, session->next_crypto->e,
-        session->next_crypto->y, p, ctx);
+        session->next_crypto->y, select_p(session->next_crypto->kex_type), ctx);
   }
 #endif
 
@@ -668,7 +728,9 @@ int make_sessionid(ssh_session session) {
   if (buffer_add_data(buf, session->next_crypto->server_pubkey, len) < 0) {
     goto error;
   }
-  if(session->next_crypto->kex_type == SSH_KEX_DH_GROUP1_SHA1){
+  if(session->next_crypto->kex_type == SSH_KEX_DH_GROUP1_SHA1 ||
+     session->next_crypto->kex_type == SSH_KEX_DH_GROUP14_SHA1) {
+
     num = make_bignum_string(session->next_crypto->e);
     if (num == NULL) {
       goto error;
@@ -718,6 +780,7 @@ int make_sessionid(ssh_session session) {
 
   switch(session->next_crypto->kex_type){
     case SSH_KEX_DH_GROUP1_SHA1:
+    case SSH_KEX_DH_GROUP14_SHA1:
       session->next_crypto->digest_len = SHA_DIGEST_LENGTH;
       session->next_crypto->mac_type = SSH_MAC_SHA1;
       session->next_crypto->session_id = malloc(session->next_crypto->digest_len);

src/kex.c

@@ -65,10 +65,10 @@
 #endif
 
 #ifdef HAVE_ECDH
-#define KEY_EXCHANGE "ecdh-sha2-nistp256,diffie-hellman-group1-sha1"
+#define KEY_EXCHANGE "ecdh-sha2-nistp256,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1"
 #define HOSTKEYS "ecdsa-sha2-nistp256,ssh-rsa,ssh-dss"
 #else
-#define KEY_EXCHANGE "diffie-hellman-group1-sha1"
+#define KEY_EXCHANGE "diffie-hellman-group14-sha1,diffie-hellman-group1-sha1"
 #define HOSTKEYS "ssh-rsa,ssh-dss"
 #endif
 
@@ -393,6 +393,8 @@ int ssh_kex_select_methods (ssh_session session){
     }
     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], "ecdh-sha2-nistp256") == 0){
       session->next_crypto->kex_type=SSH_KEX_ECDH_SHA2_NISTP256;
     }

src/options.c

@@ -332,7 +332,7 @@ int ssh_options_set_algo(ssh_session session, int algo,
  *              - SSH_OPTIONS_KEY_EXCHANGE:
  *                Set the key exchange method to be used (const char *,
  *                comma-separated list). ex:
- *                "ecdh-sha2-nistp256,diffie-hellman-group1-sha1"
+ *                "ecdh-sha2-nistp256,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1"
  *
  *              - SSH_OPTIONS_HOSTKEYS:
  *                Set the preferred server host key types (const char *,

src/packet_cb.c

@@ -94,6 +94,7 @@ SSH_PACKET_CALLBACK(ssh_packet_dh_reply){
   }
   switch(session->next_crypto->kex_type){
     case SSH_KEX_DH_GROUP1_SHA1:
+    case SSH_KEX_DH_GROUP14_SHA1:
       rc=ssh_client_dh_reply(session, packet);
       break;
 #ifdef HAVE_ECDH

src/server.c

@@ -177,6 +177,7 @@ SSH_PACKET_CALLBACK(ssh_packet_kexdh_init){
   }
   switch(session->next_crypto->kex_type){
       case SSH_KEX_DH_GROUP1_SHA1:
+      case SSH_KEX_DH_GROUP14_SHA1:
         rc=ssh_server_kexdh_init(session, packet);
         break;
   #ifdef HAVE_ECDH