From e689375e452fc6b3e1fd31b0e9819d1600bd7704 Mon Sep 17 00:00:00 2001 From: Dmitriy Kuznetsov Date: Tue, 4 Sep 2012 16:16:15 +0200 Subject: dh: Add support for diffie-hellman-group14-sha1. --- include/libssh/crypto.h | 2 + src/client.c | 1 + src/dh.c | 101 +++++++++++++++++++++++++++++++++++++++--------- src/kex.c | 6 ++- src/options.c | 2 +- src/packet_cb.c | 1 + src/server.c | 1 + 7 files changed, 92 insertions(+), 22 deletions(-) diff --git a/include/libssh/crypto.h b/include/libssh/crypto.h index 498835e2..388a52b8 100644 --- a/include/libssh/crypto.h +++ b/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 }; diff --git a/src/client.c b/src/client.c index d5c3921c..eaef21c7 100644 --- a/src/client.c +++ b/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 diff --git a/src/dh.c b/src/dh.c index 42cc6e6b..4cd34b03 100644 --- a/src/dh.c +++ b/src/dh.c @@ -5,6 +5,7 @@ * * Copyright (c) 2003-2008 by Aris Adamantiadis * Copyright (c) 2009 by Andreas Schneider + * Copyright (c) 2012 by Dmitriy Kuznetsov * * 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 #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); - if (p == NULL) { + bignum_bin2bn(p_group1_value, P_GROUP1_LEN, &p_group1); + 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(); - if (p == NULL) { + p_group1 = bignum_new(); + 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); - p = NULL; + bignum_free(p_group1); + 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); diff --git a/src/kex.c b/src/kex.c index 81f7f1ac..c23e2982 100644 --- a/src/kex.c +++ b/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; } diff --git a/src/options.c b/src/options.c index e96c74ae..72154cf7 100644 --- a/src/options.c +++ b/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 *, diff --git a/src/packet_cb.c b/src/packet_cb.c index df284eff..f236fe57 100644 --- a/src/packet_cb.c +++ b/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 diff --git a/src/server.c b/src/server.c index ac3fec30..b418081b 100644 --- a/src/server.c +++ b/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 -- cgit v1.2.3