blob: 216514dc4f0d0777273c025c96028962c17e56a7 [file] [log] [blame]
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* ====================================================================
* Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* ====================================================================
* Copyright 2005 Nokia. All rights reserved.
*
* The portions of the attached software ("Contribution") is developed by
* Nokia Corporation and is licensed pursuant to the OpenSSL open source
* license.
*
* The Contribution, originally written by Mika Kousa and Pasi Eronen of
* Nokia Corporation, consists of the "PSK" (Pre-Shared Key) ciphersuites
* support (see RFC 4279) to OpenSSL.
*
* No patent licenses or other rights except those expressly stated in
* the OpenSSL open source license shall be deemed granted or received
* expressly, by implication, estoppel, or otherwise.
*
* No assurances are provided by Nokia that the Contribution does not
* infringe the patent or other intellectual property rights of any third
* party or that the license provides you with all the necessary rights
* to make use of the Contribution.
*
* THE SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. IN
* ADDITION TO THE DISCLAIMERS INCLUDED IN THE LICENSE, NOKIA
* SPECIFICALLY DISCLAIMS ANY LIABILITY FOR CLAIMS BROUGHT BY YOU OR ANY
* OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OR
* OTHERWISE. */
#include <openssl/ssl.h>
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/md5.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/rand.h>
#include "internal.h"
/* tls1_P_hash computes the TLS P_<hash> function as described in RFC 5246,
* section 5. It XORs |out_len| bytes to |out|, using |md| as the hash and
* |secret| as the secret. |seed1| through |seed3| are concatenated to form the
* seed parameter. It returns one on success and zero on failure. */
static int tls1_P_hash(uint8_t *out, size_t out_len, const EVP_MD *md,
const uint8_t *secret, size_t secret_len,
const uint8_t *seed1, size_t seed1_len,
const uint8_t *seed2, size_t seed2_len,
const uint8_t *seed3, size_t seed3_len) {
HMAC_CTX ctx, ctx_tmp, ctx_init;
uint8_t A1[EVP_MAX_MD_SIZE];
unsigned A1_len;
int ret = 0;
size_t chunk = EVP_MD_size(md);
HMAC_CTX_init(&ctx);
HMAC_CTX_init(&ctx_tmp);
HMAC_CTX_init(&ctx_init);
if (!HMAC_Init_ex(&ctx_init, secret, secret_len, md, NULL) ||
!HMAC_CTX_copy_ex(&ctx, &ctx_init) ||
!HMAC_Update(&ctx, seed1, seed1_len) ||
!HMAC_Update(&ctx, seed2, seed2_len) ||
!HMAC_Update(&ctx, seed3, seed3_len) ||
!HMAC_Final(&ctx, A1, &A1_len)) {
goto err;
}
for (;;) {
unsigned len;
uint8_t hmac[EVP_MAX_MD_SIZE];
if (!HMAC_CTX_copy_ex(&ctx, &ctx_init) ||
!HMAC_Update(&ctx, A1, A1_len) ||
/* Save a copy of |ctx| to compute the next A1 value below. */
(out_len > chunk && !HMAC_CTX_copy_ex(&ctx_tmp, &ctx)) ||
!HMAC_Update(&ctx, seed1, seed1_len) ||
!HMAC_Update(&ctx, seed2, seed2_len) ||
!HMAC_Update(&ctx, seed3, seed3_len) ||
!HMAC_Final(&ctx, hmac, &len)) {
goto err;
}
assert(len == chunk);
/* XOR the result into |out|. */
if (len > out_len) {
len = out_len;
}
unsigned i;
for (i = 0; i < len; i++) {
out[i] ^= hmac[i];
}
out += len;
out_len -= len;
if (out_len == 0) {
break;
}
/* Calculate the next A1 value. */
if (!HMAC_Final(&ctx_tmp, A1, &A1_len)) {
goto err;
}
}
ret = 1;
err:
HMAC_CTX_cleanup(&ctx);
HMAC_CTX_cleanup(&ctx_tmp);
HMAC_CTX_cleanup(&ctx_init);
OPENSSL_cleanse(A1, sizeof(A1));
return ret;
}
static int tls1_prf(const SSL *ssl, uint8_t *out, size_t out_len,
const uint8_t *secret, size_t secret_len, const char *label,
size_t label_len, const uint8_t *seed1, size_t seed1_len,
const uint8_t *seed2, size_t seed2_len) {
if (out_len == 0) {
return 1;
}
memset(out, 0, out_len);
uint32_t algorithm_prf = ssl_get_algorithm_prf(ssl);
if (algorithm_prf == SSL_HANDSHAKE_MAC_DEFAULT) {
/* If using the MD5/SHA1 PRF, |secret| is partitioned between SHA-1 and
* MD5, MD5 first. */
size_t secret_half = secret_len - (secret_len / 2);
if (!tls1_P_hash(out, out_len, EVP_md5(), secret, secret_half,
(const uint8_t *)label, label_len, seed1, seed1_len, seed2,
seed2_len)) {
return 0;
}
/* Note that, if |secret_len| is odd, the two halves share a byte. */
secret = secret + (secret_len - secret_half);
secret_len = secret_half;
}
if (!tls1_P_hash(out, out_len, ssl_get_handshake_digest(algorithm_prf),
secret, secret_len, (const uint8_t *)label, label_len,
seed1, seed1_len, seed2, seed2_len)) {
return 0;
}
return 1;
}
int tls1_change_cipher_state(SSL *ssl, int which) {
/* Ensure the key block is set up. */
if (!tls1_setup_key_block(ssl)) {
return 0;
}
/* is_read is true if we have just read a ChangeCipherSpec message - i.e. we
* need to update the read cipherspec. Otherwise we have just written one. */
const char is_read = (which & SSL3_CC_READ) != 0;
/* use_client_keys is true if we wish to use the keys for the "client write"
* direction. This is the case if we're a client sending a ChangeCipherSpec,
* or a server reading a client's ChangeCipherSpec. */
const char use_client_keys = which == SSL3_CHANGE_CIPHER_CLIENT_WRITE ||
which == SSL3_CHANGE_CIPHER_SERVER_READ;
size_t mac_secret_len = ssl->s3->tmp.new_mac_secret_len;
size_t key_len = ssl->s3->tmp.new_key_len;
size_t iv_len = ssl->s3->tmp.new_fixed_iv_len;
assert((mac_secret_len + key_len + iv_len) * 2 ==
ssl->s3->tmp.key_block_length);
const uint8_t *key_data = ssl->s3->tmp.key_block;
const uint8_t *client_write_mac_secret = key_data;
key_data += mac_secret_len;
const uint8_t *server_write_mac_secret = key_data;
key_data += mac_secret_len;
const uint8_t *client_write_key = key_data;
key_data += key_len;
const uint8_t *server_write_key = key_data;
key_data += key_len;
const uint8_t *client_write_iv = key_data;
key_data += iv_len;
const uint8_t *server_write_iv = key_data;
key_data += iv_len;
const uint8_t *mac_secret, *key, *iv;
if (use_client_keys) {
mac_secret = client_write_mac_secret;
key = client_write_key;
iv = client_write_iv;
} else {
mac_secret = server_write_mac_secret;
key = server_write_key;
iv = server_write_iv;
}
SSL_AEAD_CTX *aead_ctx =
SSL_AEAD_CTX_new(is_read ? evp_aead_open : evp_aead_seal,
ssl3_protocol_version(ssl), ssl->s3->tmp.new_cipher, key,
key_len, mac_secret, mac_secret_len, iv, iv_len);
if (aead_ctx == NULL) {
return 0;
}
if (is_read) {
ssl_set_read_state(ssl, aead_ctx);
} else {
ssl_set_write_state(ssl, aead_ctx);
}
return 1;
}
size_t SSL_get_key_block_len(const SSL *ssl) {
return 2 * ((size_t)ssl->s3->tmp.new_mac_secret_len +
(size_t)ssl->s3->tmp.new_key_len +
(size_t)ssl->s3->tmp.new_fixed_iv_len);
}
int SSL_generate_key_block(const SSL *ssl, uint8_t *out, size_t out_len) {
return ssl->s3->enc_method->prf(
ssl, out, out_len, ssl->session->master_key,
ssl->session->master_key_length, TLS_MD_KEY_EXPANSION_CONST,
TLS_MD_KEY_EXPANSION_CONST_SIZE, ssl->s3->server_random, SSL3_RANDOM_SIZE,
ssl->s3->client_random, SSL3_RANDOM_SIZE);
}
int tls1_setup_key_block(SSL *ssl) {
if (ssl->s3->tmp.key_block_length != 0) {
return 1;
}
const EVP_AEAD *aead = NULL;
size_t mac_secret_len, fixed_iv_len;
if (ssl->session->cipher == NULL ||
!ssl_cipher_get_evp_aead(&aead, &mac_secret_len, &fixed_iv_len,
ssl->session->cipher,
ssl3_protocol_version(ssl))) {
OPENSSL_PUT_ERROR(SSL, SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
return 0;
}
size_t key_len = EVP_AEAD_key_length(aead);
if (mac_secret_len > 0) {
/* For "stateful" AEADs (i.e. compatibility with pre-AEAD cipher suites) the
* key length reported by |EVP_AEAD_key_length| will include the MAC key
* bytes and initial implicit IV. */
if (key_len < mac_secret_len + fixed_iv_len) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return 0;
}
key_len -= mac_secret_len + fixed_iv_len;
}
assert(mac_secret_len < 256);
assert(key_len < 256);
assert(fixed_iv_len < 256);
ssl->s3->tmp.new_mac_secret_len = (uint8_t)mac_secret_len;
ssl->s3->tmp.new_key_len = (uint8_t)key_len;
ssl->s3->tmp.new_fixed_iv_len = (uint8_t)fixed_iv_len;
size_t key_block_len = SSL_get_key_block_len(ssl);
ssl3_cleanup_key_block(ssl);
uint8_t *keyblock = OPENSSL_malloc(key_block_len);
if (keyblock == NULL) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return 0;
}
if (!SSL_generate_key_block(ssl, keyblock, key_block_len)) {
OPENSSL_free(keyblock);
return 0;
}
assert(key_block_len < 256);
ssl->s3->tmp.key_block_length = (uint8_t)key_block_len;
ssl->s3->tmp.key_block = keyblock;
return 1;
}
static int tls1_cert_verify_mac(SSL *ssl, int md_nid, uint8_t *out) {
const EVP_MD_CTX *ctx_template;
if (md_nid == NID_md5) {
ctx_template = &ssl->s3->handshake_md5;
} else if (md_nid == EVP_MD_CTX_type(&ssl->s3->handshake_hash)) {
ctx_template = &ssl->s3->handshake_hash;
} else {
OPENSSL_PUT_ERROR(SSL, SSL_R_NO_REQUIRED_DIGEST);
return 0;
}
EVP_MD_CTX ctx;
EVP_MD_CTX_init(&ctx);
if (!EVP_MD_CTX_copy_ex(&ctx, ctx_template)) {
EVP_MD_CTX_cleanup(&ctx);
return 0;
}
unsigned ret;
EVP_DigestFinal_ex(&ctx, out, &ret);
EVP_MD_CTX_cleanup(&ctx);
return ret;
}
static int append_digest(const EVP_MD_CTX *ctx, uint8_t *out, size_t *out_len,
size_t max_out) {
int ret = 0;
EVP_MD_CTX ctx_copy;
EVP_MD_CTX_init(&ctx_copy);
if (EVP_MD_CTX_size(ctx) > max_out) {
OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
goto err;
}
unsigned len;
if (!EVP_MD_CTX_copy_ex(&ctx_copy, ctx) ||
!EVP_DigestFinal_ex(&ctx_copy, out, &len)) {
goto err;
}
assert(len == EVP_MD_CTX_size(ctx));
*out_len = len;
ret = 1;
err:
EVP_MD_CTX_cleanup(&ctx_copy);
return ret;
}
/* tls1_handshake_digest calculates the current handshake hash and writes it to
* |out|, which has space for |out_len| bytes. It returns the number of bytes
* written or -1 in the event of an error. This function works on a copy of the
* underlying digests so can be called multiple times and prior to the final
* update etc. */
int tls1_handshake_digest(SSL *ssl, uint8_t *out, size_t out_len) {
size_t md5_len = 0;
if (EVP_MD_CTX_md(&ssl->s3->handshake_md5) != NULL &&
!append_digest(&ssl->s3->handshake_md5, out, &md5_len, out_len)) {
return -1;
}
size_t len;
if (!append_digest(&ssl->s3->handshake_hash, out + md5_len, &len,
out_len - md5_len)) {
return -1;
}
return (int)(md5_len + len);
}
static int tls1_final_finish_mac(SSL *ssl, int from_server, uint8_t *out) {
/* At this point, the handshake should have released the handshake buffer on
* its own. */
assert(ssl->s3->handshake_buffer == NULL);
const char *label = TLS_MD_CLIENT_FINISH_CONST;
size_t label_len = TLS_MD_SERVER_FINISH_CONST_SIZE;
if (from_server) {
label = TLS_MD_SERVER_FINISH_CONST;
label_len = TLS_MD_SERVER_FINISH_CONST_SIZE;
}
uint8_t buf[EVP_MAX_MD_SIZE];
int digests_len = tls1_handshake_digest(ssl, buf, sizeof(buf));
if (digests_len < 0) {
return 0;
}
static const size_t kFinishedLen = 12;
if (!ssl->s3->enc_method->prf(ssl, out, kFinishedLen,
ssl->session->master_key,
ssl->session->master_key_length, label,
label_len, buf, digests_len, NULL, 0)) {
return 0;
}
return (int)kFinishedLen;
}
int tls1_generate_master_secret(SSL *ssl, uint8_t *out,
const uint8_t *premaster,
size_t premaster_len) {
if (ssl->s3->tmp.extended_master_secret) {
uint8_t digests[EVP_MAX_MD_SIZE];
int digests_len = tls1_handshake_digest(ssl, digests, sizeof(digests));
if (digests_len == -1) {
return 0;
}
if (!ssl->s3->enc_method->prf(ssl, out, SSL3_MASTER_SECRET_SIZE, premaster,
premaster_len,
TLS_MD_EXTENDED_MASTER_SECRET_CONST,
TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE,
digests, digests_len, NULL, 0)) {
return 0;
}
} else {
if (!ssl->s3->enc_method->prf(ssl, out, SSL3_MASTER_SECRET_SIZE, premaster,
premaster_len, TLS_MD_MASTER_SECRET_CONST,
TLS_MD_MASTER_SECRET_CONST_SIZE,
ssl->s3->client_random, SSL3_RANDOM_SIZE,
ssl->s3->server_random, SSL3_RANDOM_SIZE)) {
return 0;
}
}
return SSL3_MASTER_SECRET_SIZE;
}
int SSL_export_keying_material(SSL *ssl, uint8_t *out, size_t out_len,
const char *label, size_t label_len,
const uint8_t *context, size_t context_len,
int use_context) {
if (!ssl->s3->have_version || ssl->version == SSL3_VERSION) {
return 0;
}
size_t seed_len = 2 * SSL3_RANDOM_SIZE;
if (use_context) {
if (context_len >= 1u << 16) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return 0;
}
seed_len += 2 + context_len;
}
uint8_t *seed = OPENSSL_malloc(seed_len);
if (seed == NULL) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return 0;
}
memcpy(seed, ssl->s3->client_random, SSL3_RANDOM_SIZE);
memcpy(seed + SSL3_RANDOM_SIZE, ssl->s3->server_random, SSL3_RANDOM_SIZE);
if (use_context) {
seed[2 * SSL3_RANDOM_SIZE] = (uint8_t)(context_len >> 8);
seed[2 * SSL3_RANDOM_SIZE + 1] = (uint8_t)context_len;
memcpy(seed + 2 * SSL3_RANDOM_SIZE + 2, context, context_len);
}
int ret =
ssl->s3->enc_method->prf(ssl, out, out_len, ssl->session->master_key,
ssl->session->master_key_length, label,
label_len, seed, seed_len, NULL, 0);
OPENSSL_free(seed);
return ret;
}
const SSL3_ENC_METHOD TLSv1_enc_data = {
tls1_prf,
tls1_final_finish_mac,
tls1_cert_verify_mac,
};