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boringssl/ssl/t1_enc.c
Adam Langley fcf25833bc Reformat the rest of ssl/. 
Change-Id: I7dc264f7e29b3ba8be4c717583467edf71bf8dd9
2014-12-18 17:43:03 -08:00

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/* 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 <stdio.h>
#include <assert.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 "ssl_locl.h"
/* seed1 through seed3 are virtually concatenated */
static int tls1_P_hash(const EVP_MD *md, const uint8_t *sec, int sec_len,
const void *seed1, int seed1_len,
const void *seed2, int seed2_len,
const void *seed3, int seed3_len,
uint8_t *out, int olen) {
int chunk;
size_t j;
EVP_MD_CTX ctx, ctx_tmp, ctx_init;
EVP_PKEY *mac_key;
uint8_t A1[EVP_MAX_MD_SIZE];
size_t A1_len;
int ret = 0;
chunk = EVP_MD_size(md);
EVP_MD_CTX_init(&ctx);
EVP_MD_CTX_init(&ctx_tmp);
EVP_MD_CTX_init(&ctx_init);
mac_key = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, sec, sec_len);
A1_len = EVP_MAX_MD_SIZE;
if (!mac_key ||
!EVP_DigestSignInit(&ctx_init, NULL, md, NULL, mac_key) ||
!EVP_MD_CTX_copy_ex(&ctx, &ctx_init) ||
(seed1 && !EVP_DigestSignUpdate(&ctx, seed1, seed1_len)) ||
(seed2 && !EVP_DigestSignUpdate(&ctx, seed2, seed2_len)) ||
(seed3 && !EVP_DigestSignUpdate(&ctx, seed3, seed3_len)) ||
!EVP_DigestSignFinal(&ctx, A1, &A1_len)) {
goto err;
}
for (;;) {
/* Reinit mac contexts */
if (!EVP_MD_CTX_copy_ex(&ctx, &ctx_init) ||
!EVP_DigestSignUpdate(&ctx, A1, A1_len) ||
(olen > chunk && !EVP_MD_CTX_copy_ex(&ctx_tmp, &ctx)) ||
(seed1 && !EVP_DigestSignUpdate(&ctx, seed1, seed1_len)) ||
(seed2 && !EVP_DigestSignUpdate(&ctx, seed2, seed2_len)) ||
(seed3 && !EVP_DigestSignUpdate(&ctx, seed3, seed3_len))) {
goto err;
}
if (olen > chunk) {
j = olen;
if (!EVP_DigestSignFinal(&ctx, out, &j)) {
goto err;
}
out += j;
olen -= j;
/* calc the next A1 value */
A1_len = EVP_MAX_MD_SIZE;
if (!EVP_DigestSignFinal(&ctx_tmp, A1, &A1_len)) {
goto err;
}
} else {
/* last one */
A1_len = EVP_MAX_MD_SIZE;
if (!EVP_DigestSignFinal(&ctx, A1, &A1_len)) {
goto err;
}
memcpy(out, A1, olen);
break;
}
}
ret = 1;
err:
EVP_PKEY_free(mac_key);
EVP_MD_CTX_cleanup(&ctx);
EVP_MD_CTX_cleanup(&ctx_tmp);
EVP_MD_CTX_cleanup(&ctx_init);
OPENSSL_cleanse(A1, sizeof(A1));
return ret;
}
/* seed1 through seed3 are virtually concatenated */
static int tls1_PRF(long digest_mask,
const void *seed1, int seed1_len,
const void *seed2, int seed2_len,
const void *seed3, int seed3_len,
const uint8_t *sec, int slen,
uint8_t *out1, uint8_t *out2, int olen) {
int len, i, idx, count;
const uint8_t *S1;
long m;
const EVP_MD *md;
int ret = 0;
/* Count number of digests and partition sec evenly */
count = 0;
for (idx = 0; ssl_get_handshake_digest(idx, &m, &md); idx++) {
if ((m << TLS1_PRF_DGST_SHIFT) & digest_mask) {
count++;
}
}
len = slen / count;
if (count == 1) {
slen = 0;
}
S1 = sec;
memset(out1, 0, olen);
for (idx = 0; ssl_get_handshake_digest(idx, &m, &md); idx++) {
if ((m << TLS1_PRF_DGST_SHIFT) & digest_mask) {
if (!md) {
OPENSSL_PUT_ERROR(SSL, tls1_PRF, SSL_R_UNSUPPORTED_DIGEST_TYPE);
goto err;
}
if (!tls1_P_hash(md, S1, len + (slen & 1), seed1, seed1_len, seed2,
seed2_len, seed3, seed3_len, out2, olen)) {
goto err;
}
S1 += len;
for (i = 0; i < olen; i++) {
out1[i] ^= out2[i];
}
}
}
ret = 1;
err:
return ret;
}
static int tls1_generate_key_block(SSL *s, uint8_t *km, uint8_t *tmp, int num) {
return tls1_PRF(ssl_get_algorithm2(s), TLS_MD_KEY_EXPANSION_CONST,
TLS_MD_KEY_EXPANSION_CONST_SIZE, s->s3->server_random,
SSL3_RANDOM_SIZE, s->s3->client_random, SSL3_RANDOM_SIZE,
s->session->master_key, s->session->master_key_length, km,
tmp, num);
}
/* tls1_aead_ctx_init allocates |*aead_ctx|, if needed and returns 1. It
* returns 0 on malloc error. */
static int tls1_aead_ctx_init(SSL_AEAD_CTX **aead_ctx) {
if (*aead_ctx != NULL) {
EVP_AEAD_CTX_cleanup(&(*aead_ctx)->ctx);
} else {
*aead_ctx = (SSL_AEAD_CTX *)OPENSSL_malloc(sizeof(SSL_AEAD_CTX));
if (*aead_ctx == NULL) {
OPENSSL_PUT_ERROR(SSL, tls1_aead_ctx_init, ERR_R_MALLOC_FAILURE);
return 0;
}
}
return 1;
}
static void tls1_cleanup_enc_ctx(EVP_CIPHER_CTX **ctx) {
if (*ctx != NULL) {
EVP_CIPHER_CTX_free(*ctx);
}
*ctx = NULL;
}
static void tls1_cleanup_hash_ctx(EVP_MD_CTX **ctx) {
if (*ctx != NULL) {
EVP_MD_CTX_destroy(*ctx);
}
*ctx = NULL;
}
static int tls1_change_cipher_state_aead(SSL *s, char is_read,
const uint8_t *key, unsigned key_len,
const uint8_t *iv, unsigned iv_len,
const uint8_t *mac_secret,
unsigned mac_secret_len) {
const EVP_AEAD *aead = s->s3->tmp.new_aead;
SSL_AEAD_CTX *aead_ctx;
/* mac_key_and_key is used to merge the MAC and cipher keys for an AEAD which
* simulates pre-AEAD cipher suites. It needs to be large enough to cope with
* the largest pair of keys. */
uint8_t mac_key_and_key[32 /* HMAC(SHA256) */ + 32 /* AES-256 */];
if (is_read) {
tls1_cleanup_enc_ctx(&s->enc_read_ctx);
tls1_cleanup_hash_ctx(&s->read_hash);
} else {
tls1_cleanup_enc_ctx(&s->enc_write_ctx);
tls1_cleanup_hash_ctx(&s->write_hash);
}
if (mac_secret_len > 0) {
/* This is a "stateful" AEAD (for compatibility with pre-AEAD cipher
* suites). */
if (mac_secret_len + key_len > sizeof(mac_key_and_key)) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state_aead,
ERR_R_INTERNAL_ERROR);
return 0;
}
memcpy(mac_key_and_key, mac_secret, mac_secret_len);
memcpy(mac_key_and_key + mac_secret_len, key, key_len);
key = mac_key_and_key;
key_len += mac_secret_len;
}
if (is_read) {
if (!tls1_aead_ctx_init(&s->aead_read_ctx)) {
return 0;
}
aead_ctx = s->aead_read_ctx;
} else {
if (!tls1_aead_ctx_init(&s->aead_write_ctx)) {
return 0;
}
aead_ctx = s->aead_write_ctx;
}
if (!EVP_AEAD_CTX_init(&aead_ctx->ctx, aead, key, key_len,
EVP_AEAD_DEFAULT_TAG_LENGTH, NULL /* engine */)) {
OPENSSL_free(aead_ctx);
if (is_read) {
s->aead_read_ctx = NULL;
} else {
s->aead_write_ctx = NULL;
}
return 0;
}
if (iv_len > sizeof(aead_ctx->fixed_nonce)) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state_aead, ERR_R_INTERNAL_ERROR);
return 0;
}
memcpy(aead_ctx->fixed_nonce, iv, iv_len);
aead_ctx->fixed_nonce_len = iv_len;
aead_ctx->variable_nonce_len = 8; /* correct for all true AEADs so far. */
if (s->s3->tmp.new_cipher->algorithm2 & SSL_CIPHER_ALGORITHM2_STATEFUL_AEAD) {
aead_ctx->variable_nonce_len = 0;
}
aead_ctx->variable_nonce_included_in_record =
(s->s3->tmp.new_cipher->algorithm2 &
SSL_CIPHER_ALGORITHM2_VARIABLE_NONCE_INCLUDED_IN_RECORD) != 0;
if (aead_ctx->variable_nonce_len + aead_ctx->fixed_nonce_len !=
EVP_AEAD_nonce_length(aead)) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state_aead, ERR_R_INTERNAL_ERROR);
return 0;
}
aead_ctx->tag_len = EVP_AEAD_max_overhead(aead);
return 1;
}
static void tls1_cleanup_aead_ctx(SSL_AEAD_CTX **ctx) {
if (*ctx != NULL) {
EVP_AEAD_CTX_cleanup(&(*ctx)->ctx);
OPENSSL_free(*ctx);
}
*ctx = NULL;
}
/* tls1_change_cipher_state_cipher performs the work needed to switch cipher
* states when using EVP_CIPHER. The argument |is_read| is true iff this
* function is being called due to reading, as opposed to writing, a
* ChangeCipherSpec message. In order to support export ciphersuites,
* use_client_keys indicates whether the key material provided is in the
* "client write" direction. */
static int tls1_change_cipher_state_cipher(SSL *s, char is_read,
char use_client_keys,
const uint8_t *mac_secret,
unsigned mac_secret_len,
const uint8_t *key, unsigned key_len,
const uint8_t *iv, unsigned iv_len) {
const EVP_CIPHER *cipher = s->s3->tmp.new_sym_enc;
EVP_CIPHER_CTX *cipher_ctx;
EVP_MD_CTX *mac_ctx;
if (is_read) {
tls1_cleanup_aead_ctx(&s->aead_read_ctx);
} else {
tls1_cleanup_aead_ctx(&s->aead_write_ctx);
}
if (is_read) {
if (s->enc_read_ctx != NULL && !SSL_IS_DTLS(s)) {
EVP_CIPHER_CTX_cleanup(s->enc_read_ctx);
} else if ((s->enc_read_ctx = EVP_CIPHER_CTX_new()) == NULL) {
goto err;
}
cipher_ctx = s->enc_read_ctx;
mac_ctx = ssl_replace_hash(&s->read_hash, NULL);
if (mac_ctx == NULL) {
goto err;
}
memcpy(s->s3->read_mac_secret, mac_secret, mac_secret_len);
s->s3->read_mac_secret_size = mac_secret_len;
} else {
/* When updating the write contexts for DTLS, we do not wish to free the
* old ones because DTLS stores pointers to them in order to implement
* retransmission. */
if (s->enc_write_ctx != NULL && !SSL_IS_DTLS(s)) {
EVP_CIPHER_CTX_cleanup(s->enc_write_ctx);
} else {
s->enc_write_ctx = OPENSSL_malloc(sizeof(EVP_CIPHER_CTX));
if (s->enc_write_ctx == NULL) {
goto err;
}
}
EVP_CIPHER_CTX_init(s->enc_write_ctx);
cipher_ctx = s->enc_write_ctx;
if (SSL_IS_DTLS(s)) {
/* This is the same as ssl_replace_hash, but doesn't
* free the old |s->write_hash|. */
mac_ctx = EVP_MD_CTX_create();
if (!mac_ctx) {
goto err;
}
s->write_hash = mac_ctx;
} else {
mac_ctx = ssl_replace_hash(&s->write_hash, NULL);
if (mac_ctx == NULL) {
goto err;
}
}
memcpy(s->s3->write_mac_secret, mac_secret, mac_secret_len);
s->s3->write_mac_secret_size = mac_secret_len;
}
EVP_PKEY *mac_key = EVP_PKEY_new_mac_key(s->s3->tmp.new_mac_pkey_type, NULL,
mac_secret, mac_secret_len);
if (!mac_key) {
return 0;
}
if (!EVP_DigestSignInit(mac_ctx, NULL, s->s3->tmp.new_hash, NULL, mac_key)) {
EVP_PKEY_free(mac_key);
goto err;
}
EVP_PKEY_free(mac_key);
if (!EVP_CipherInit_ex(cipher_ctx, cipher, NULL /* engine */, key, iv,
!is_read)) {
goto err;
}
return 1;
err:
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state_cipher, ERR_R_MALLOC_FAILURE);
return 0;
}
int tls1_change_cipher_state(SSL *s, int which) {
/* 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;
const uint8_t *client_write_mac_secret, *server_write_mac_secret, *mac_secret;
const uint8_t *client_write_key, *server_write_key, *key;
const uint8_t *client_write_iv, *server_write_iv, *iv;
const EVP_CIPHER *cipher = s->s3->tmp.new_sym_enc;
const EVP_AEAD *aead = s->s3->tmp.new_aead;
unsigned key_len, iv_len, mac_secret_len;
const uint8_t *key_data;
/* Reset sequence number to zero. */
if (!SSL_IS_DTLS(s)) {
memset(is_read ? s->s3->read_sequence : s->s3->write_sequence, 0, 8);
}
mac_secret_len = s->s3->tmp.new_mac_secret_size;
if (aead != NULL) {
key_len = EVP_AEAD_key_length(aead);
/* 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. */
if (key_len < mac_secret_len) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state, ERR_R_INTERNAL_ERROR);
return 0;
}
key_len -= mac_secret_len;
iv_len = SSL_CIPHER_AEAD_FIXED_NONCE_LEN(s->s3->tmp.new_cipher);
} else {
key_len = EVP_CIPHER_key_length(cipher);
iv_len = EVP_CIPHER_iv_length(cipher);
}
key_data = s->s3->tmp.key_block;
client_write_mac_secret = key_data;
key_data += mac_secret_len;
server_write_mac_secret = key_data;
key_data += mac_secret_len;
client_write_key = key_data;
key_data += key_len;
server_write_key = key_data;
key_data += key_len;
client_write_iv = key_data;
key_data += iv_len;
server_write_iv = key_data;
key_data += iv_len;
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;
}
if (key_data - s->s3->tmp.key_block != s->s3->tmp.key_block_length) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state, ERR_R_INTERNAL_ERROR);
return 0;
}
if (aead != NULL) {
if (!tls1_change_cipher_state_aead(s, is_read, key, key_len, iv, iv_len,
mac_secret, mac_secret_len)) {
return 0;
}
} else {
if (!tls1_change_cipher_state_cipher(s, is_read, use_client_keys,
mac_secret, mac_secret_len, key,
key_len, iv, iv_len)) {
return 0;
}
}
return 1;
}
int tls1_setup_key_block(SSL *s) {
uint8_t *p1, *p2 = NULL;
const EVP_CIPHER *c = NULL;
const EVP_MD *hash = NULL;
const EVP_AEAD *aead = NULL;
int num;
int mac_type = NID_undef, mac_secret_size = 0;
int ret = 0;
unsigned key_len, iv_len;
if (s->s3->tmp.key_block_length != 0) {
return 1;
}
if (s->session->cipher &&
((s->session->cipher->algorithm2 & SSL_CIPHER_ALGORITHM2_AEAD) ||
(s->session->cipher->algorithm2 &
SSL_CIPHER_ALGORITHM2_STATEFUL_AEAD))) {
if (!ssl_cipher_get_evp_aead(s->session, &aead)) {
goto cipher_unavailable_err;
}
key_len = EVP_AEAD_key_length(aead);
iv_len = SSL_CIPHER_AEAD_FIXED_NONCE_LEN(s->session->cipher);
if ((s->session->cipher->algorithm2 &
SSL_CIPHER_ALGORITHM2_STATEFUL_AEAD) &&
!ssl_cipher_get_mac(s->session, &hash, &mac_type, &mac_secret_size)) {
goto cipher_unavailable_err;
}
/* 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. */
if (key_len < (size_t)mac_secret_size) {
OPENSSL_PUT_ERROR(SSL, tls1_change_cipher_state, ERR_R_INTERNAL_ERROR);
return 0;
}
key_len -= mac_secret_size;
} else {
if (!ssl_cipher_get_evp(s->session, &c, &hash, &mac_type,
&mac_secret_size)) {
goto cipher_unavailable_err;
}
key_len = EVP_CIPHER_key_length(c);
iv_len = EVP_CIPHER_iv_length(c);
}
s->s3->tmp.new_aead = aead;
s->s3->tmp.new_sym_enc = c;
s->s3->tmp.new_hash = hash;
s->s3->tmp.new_mac_pkey_type = mac_type;
s->s3->tmp.new_mac_secret_size = mac_secret_size;
num = key_len + mac_secret_size + iv_len;
num *= 2;
ssl3_cleanup_key_block(s);
p1 = (uint8_t *)OPENSSL_malloc(num);
if (p1 == NULL) {
OPENSSL_PUT_ERROR(SSL, tls1_setup_key_block, ERR_R_MALLOC_FAILURE);
goto err;
}
s->s3->tmp.key_block_length = num;
s->s3->tmp.key_block = p1;
p2 = (uint8_t *)OPENSSL_malloc(num);
if (p2 == NULL) {
OPENSSL_PUT_ERROR(SSL, tls1_setup_key_block, ERR_R_MALLOC_FAILURE);
goto err;
}
if (!tls1_generate_key_block(s, p1, p2, num)) {
goto err;
}
if (!SSL_USE_EXPLICIT_IV(s) &&
(s->mode & SSL_MODE_CBC_RECORD_SPLITTING) != 0) {
/* enable vulnerability countermeasure for CBC ciphers with known-IV
* problem (http://www.openssl.org/~bodo/tls-cbc.txt). */
s->s3->need_record_splitting = 1;
if (s->session->cipher != NULL &&
s->session->cipher->algorithm_enc == SSL_RC4) {
s->s3->need_record_splitting = 0;
}
}
ret = 1;
err:
if (p2) {
OPENSSL_cleanse(p2, num);
OPENSSL_free(p2);
}
return ret;
cipher_unavailable_err:
OPENSSL_PUT_ERROR(SSL, tls1_setup_key_block,
SSL_R_CIPHER_OR_HASH_UNAVAILABLE);
return 0;
}
/* tls1_enc encrypts/decrypts the record in |s->wrec| / |s->rrec|,
* respectively.
*
* Returns:
* 0: (in non-constant time) if the record is publically invalid (i.e. too
* short etc).
* 1: if the record's padding is valid / the encryption was successful.
* -1: if the record's padding/AEAD-authenticator is invalid or, if sending,
* an internal error occured. */
int tls1_enc(SSL *s, int send) {
SSL3_RECORD *rec;
EVP_CIPHER_CTX *ds;
unsigned long l;
int bs, i, j, k, pad = 0, ret, mac_size = 0;
const EVP_CIPHER *enc;
const SSL_AEAD_CTX *aead;
if (send) {
rec = &s->s3->wrec;
aead = s->aead_write_ctx;
} else {
rec = &s->s3->rrec;
aead = s->aead_read_ctx;
}
if (aead) {
uint8_t ad[13], *seq, *in, *out, nonce[16];
unsigned nonce_used;
size_t n;
seq = send ? s->s3->write_sequence : s->s3->read_sequence;
if (SSL_IS_DTLS(s)) {
uint8_t dtlsseq[9], *p = dtlsseq;
s2n(send ? s->d1->w_epoch : s->d1->r_epoch, p);
memcpy(p, &seq[2], 6);
memcpy(ad, dtlsseq, 8);
} else {
memcpy(ad, seq, 8);
for (i = 7; i >= 0; i--) {
++seq[i];
if (seq[i] != 0) {
break;
}
}
}
ad[8] = rec->type;
ad[9] = (uint8_t)(s->version >> 8);
ad[10] = (uint8_t)(s->version);
if (aead->fixed_nonce_len + aead->variable_nonce_len > sizeof(nonce) ||
aead->variable_nonce_len > 8) {
return -1; /* internal error - should never happen. */
}
memcpy(nonce, aead->fixed_nonce, aead->fixed_nonce_len);
nonce_used = aead->fixed_nonce_len;
if (send) {
size_t len = rec->length;
size_t eivlen = 0;
in = rec->input;
out = rec->data;
/* When sending we use the sequence number as the variable part of the
* nonce. */
if (aead->variable_nonce_len > 8) {
return -1;
}
memcpy(nonce + nonce_used, ad, aead->variable_nonce_len);
nonce_used += aead->variable_nonce_len;
/* in do_ssl3_write, rec->input is moved forward by variable_nonce_len in
* order to leave space for the variable nonce. Thus we can copy the
* sequence number bytes into place without overwriting any of the
* plaintext. */
if (aead->variable_nonce_included_in_record) {
memcpy(out, ad, aead->variable_nonce_len);
len -= aead->variable_nonce_len;
eivlen = aead->variable_nonce_len;
}
ad[11] = len >> 8;
ad[12] = len & 0xff;
if (!EVP_AEAD_CTX_seal(&aead->ctx, out + eivlen, &n, len + aead->tag_len,
nonce, nonce_used, in + eivlen, len, ad,
sizeof(ad))) {
return -1;
}
if (aead->variable_nonce_included_in_record) {
n += aead->variable_nonce_len;
}
} else {
/* receive */
size_t len = rec->length;
if (rec->data != rec->input) {
return -1; /* internal error - should never happen. */
}
out = in = rec->input;
if (len < aead->variable_nonce_len) {
return 0;
}
memcpy(nonce + nonce_used,
aead->variable_nonce_included_in_record ? in : ad,
aead->variable_nonce_len);
nonce_used += aead->variable_nonce_len;
if (aead->variable_nonce_included_in_record) {
in += aead->variable_nonce_len;
len -= aead->variable_nonce_len;
out += aead->variable_nonce_len;
}
if (len < aead->tag_len) {
return 0;
}
len -= aead->tag_len;
ad[11] = len >> 8;
ad[12] = len & 0xff;
if (!EVP_AEAD_CTX_open(&aead->ctx, out, &n, len, nonce, nonce_used, in,
len + aead->tag_len, ad, sizeof(ad))) {
return -1;
}
rec->data = rec->input = out;
}
rec->length = n;
return 1;
}
if (send) {
ds = s->enc_write_ctx;
rec = &(s->s3->wrec);
if (s->enc_write_ctx == NULL) {
enc = NULL;
} else {
int ivlen;
enc = EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
/* For TLSv1.1 and later explicit IV */
if (SSL_USE_EXPLICIT_IV(s) && EVP_CIPHER_mode(enc) == EVP_CIPH_CBC_MODE) {
ivlen = EVP_CIPHER_iv_length(enc);
} else {
ivlen = 0;
}
if (ivlen > 1) {
if (rec->data != rec->input) {
/* we can't write into the input stream:
* Can this ever happen?? (steve)
*/
fprintf(stderr, "%s:%d: rec->data != rec->input\n", __FILE__,
__LINE__);
} else if (!RAND_bytes(rec->input, ivlen)) {
return -1;
}
}
}
} else {
ds = s->enc_read_ctx;
rec = &(s->s3->rrec);
if (s->enc_read_ctx == NULL) {
enc = NULL;
} else {
enc = EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
}
}
if (s->session == NULL || ds == NULL || enc == NULL) {
memmove(rec->data, rec->input, rec->length);
rec->input = rec->data;
ret = 1;
} else {
l = rec->length;
bs = EVP_CIPHER_block_size(ds->cipher);
if (bs != 1 && send) {
i = bs - ((int)l % bs);
/* Add weird padding of upto 256 bytes */
/* we need to add 'i' padding bytes of value j */
j = i - 1;
for (k = (int)l; k < (int)(l + i); k++) {
rec->input[k] = j;
}
l += i;
rec->length += i;
}
if (!send && (l == 0 || l % bs != 0)) {
return 0;
}
if (!EVP_Cipher(ds, rec->data, rec->input, l)) {
return -1;
}
ret = 1;
if (EVP_MD_CTX_md(s->read_hash) != NULL) {
mac_size = EVP_MD_CTX_size(s->read_hash);
}
if (bs != 1 && !send) {
ret = tls1_cbc_remove_padding(s, rec, bs, mac_size);
}
if (pad && !send) {
rec->length -= pad;
}
}
return ret;
}
int tls1_cert_verify_mac(SSL *s, int md_nid, uint8_t *out) {
unsigned int ret;
EVP_MD_CTX ctx, *d = NULL;
int i;
if (s->s3->handshake_buffer &&
!ssl3_digest_cached_records(s, free_handshake_buffer)) {
return 0;
}
for (i = 0; i < SSL_MAX_DIGEST; i++) {
if (s->s3->handshake_dgst[i] &&
EVP_MD_CTX_type(s->s3->handshake_dgst[i]) == md_nid) {
d = s->s3->handshake_dgst[i];
break;
}
}
if (!d) {
OPENSSL_PUT_ERROR(SSL, tls1_cert_verify_mac, SSL_R_NO_REQUIRED_DIGEST);
return 0;
}
EVP_MD_CTX_init(&ctx);
EVP_MD_CTX_copy_ex(&ctx, d);
EVP_DigestFinal_ex(&ctx, out, &ret);
EVP_MD_CTX_cleanup(&ctx);
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 *s, uint8_t *out, size_t out_len) {
const EVP_MD *md;
EVP_MD_CTX ctx;
int i, err = 0, len = 0;
long mask;
EVP_MD_CTX_init(&ctx);
for (i = 0; ssl_get_handshake_digest(i, &mask, &md); i++) {
int hash_size;
unsigned int digest_len;
EVP_MD_CTX *hdgst = s->s3->handshake_dgst[i];
if ((mask & ssl_get_algorithm2(s)) == 0) {
continue;
}
hash_size = EVP_MD_size(md);
if (!hdgst ||
hash_size < 0 ||
(size_t)hash_size > out_len ||
!EVP_MD_CTX_copy_ex(&ctx, hdgst) ||
!EVP_DigestFinal_ex(&ctx, out, &digest_len) ||
digest_len != (unsigned int)hash_size /* internal error */) {
err = 1;
break;
}
out += digest_len;
out_len -= digest_len;
len += digest_len;
}
EVP_MD_CTX_cleanup(&ctx);
if (err != 0) {
return -1;
}
return len;
}
int tls1_final_finish_mac(SSL *s, const char *str, int slen, uint8_t *out) {
uint8_t buf[2 * EVP_MAX_MD_SIZE];
uint8_t buf2[12];
int err = 0;
int digests_len;
if (s->s3->handshake_buffer &&
!ssl3_digest_cached_records(s, free_handshake_buffer)) {
return 0;
}
digests_len = tls1_handshake_digest(s, buf, sizeof(buf));
if (digests_len < 0) {
err = 1;
digests_len = 0;
}
if (!tls1_PRF(ssl_get_algorithm2(s), str, slen, buf, digests_len, NULL, 0,
s->session->master_key, s->session->master_key_length, out,
buf2, sizeof buf2)) {
err = 1;
}
if (err) {
return 0;
} else {
return sizeof(buf2);
}
}
int tls1_mac(SSL *ssl, uint8_t *md, int send) {
SSL3_RECORD *rec;
uint8_t *seq;
EVP_MD_CTX *hash;
size_t md_size, orig_len;
int i, ok;
EVP_MD_CTX hmac, *mac_ctx;
uint8_t header[13];
int t;
if (send) {
rec = &ssl->s3->wrec;
seq = &ssl->s3->write_sequence[0];
hash = ssl->write_hash;
} else {
rec = &ssl->s3->rrec;
seq = &ssl->s3->read_sequence[0];
hash = ssl->read_hash;
}
t = EVP_MD_CTX_size(hash);
assert(t >= 0);
md_size = t;
mac_ctx = &hmac;
if (!EVP_MD_CTX_copy(mac_ctx, hash)) {
return -1;
}
if (SSL_IS_DTLS(ssl)) {
uint8_t dtlsseq[8], *p = dtlsseq;
s2n(send ? ssl->d1->w_epoch : ssl->d1->r_epoch, p);
memcpy(p, &seq[2], 6);
memcpy(header, dtlsseq, 8);
} else {
memcpy(header, seq, 8);
}
/* kludge: tls1_cbc_remove_padding passes padding length in rec->type */
orig_len = rec->length + md_size + ((unsigned int)rec->type >> 8);
rec->type &= 0xff;
header[8] = rec->type;
header[9] = (uint8_t)(ssl->version >> 8);
header[10] = (uint8_t)(ssl->version);
header[11] = (rec->length) >> 8;
header[12] = (rec->length) & 0xff;
if (!send && EVP_CIPHER_CTX_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
ssl3_cbc_record_digest_supported(mac_ctx)) {
/* This is a CBC-encrypted record. We must avoid leaking any timing-side
* channel information about how many blocks of data we are hashing because
* that gives an attacker a timing-oracle. */
ok = ssl3_cbc_digest_record(
mac_ctx, md, &md_size, header, rec->input, rec->length + md_size,
orig_len, ssl->s3->read_mac_secret, ssl->s3->read_mac_secret_size,
0 /* not SSLv3 */);
} else {
EVP_DigestSignUpdate(mac_ctx, header, sizeof(header));
EVP_DigestSignUpdate(mac_ctx, rec->input, rec->length);
ok = EVP_DigestSignFinal(mac_ctx, md, &md_size);
}
EVP_MD_CTX_cleanup(mac_ctx);
if (!ok) {
return -1;
}
if (!SSL_IS_DTLS(ssl)) {
for (i = 7; i >= 0; i--) {
++seq[i];
if (seq[i] != 0) {
break;
}
}
}
return md_size;
}
int tls1_generate_master_secret(SSL *s, uint8_t *out, uint8_t *p, int len) {
uint8_t buff[SSL_MAX_MASTER_KEY_LENGTH];
if (s->s3->tmp.extended_master_secret) {
uint8_t digests[2 * EVP_MAX_MD_SIZE];
int digests_len;
/* The master secret is based on the handshake hash just after sending the
* ClientKeyExchange. However, we might have a client certificate to send,
* in which case we might need different hashes for the verification and
* thus still need the handshake buffer around. Keeping both a handshake
* buffer *and* running hashes isn't yet supported so, when it comes to
* calculating the Finished hash, we'll have to hash the handshake buffer
* again. */
if (s->s3->handshake_buffer &&
!ssl3_digest_cached_records(s, dont_free_handshake_buffer)) {
return 0;
}
digests_len = tls1_handshake_digest(s, digests, sizeof(digests));
if (digests_len == -1) {
return 0;
}
tls1_PRF(ssl_get_algorithm2(s), TLS_MD_EXTENDED_MASTER_SECRET_CONST,
TLS_MD_EXTENDED_MASTER_SECRET_CONST_SIZE, digests, digests_len,
NULL, 0, p, len, s->session->master_key, buff, sizeof(buff));
} else {
tls1_PRF(ssl_get_algorithm2(s), TLS_MD_MASTER_SECRET_CONST,
TLS_MD_MASTER_SECRET_CONST_SIZE, s->s3->client_random,
SSL3_RANDOM_SIZE, s->s3->server_random, SSL3_RANDOM_SIZE, p, len,
s->session->master_key, buff, sizeof buff);
}
return SSL3_MASTER_SECRET_SIZE;
}
int tls1_export_keying_material(SSL *s, uint8_t *out, size_t olen,
const char *label, size_t llen,
const uint8_t *context, size_t contextlen,
int use_context) {
uint8_t *buff;
uint8_t *val = NULL;
size_t vallen, currentvalpos;
int ret;
buff = OPENSSL_malloc(olen);
if (buff == NULL) {
goto err2;
}
/* construct PRF arguments we construct the PRF argument ourself rather than
* passing separate values into the TLS PRF to ensure that the concatenation
* of values does not create a prohibited label. */
vallen = llen + SSL3_RANDOM_SIZE * 2;
if (use_context) {
vallen += 2 + contextlen;
}
val = OPENSSL_malloc(vallen);
if (val == NULL) {
goto err2;
}
currentvalpos = 0;
memcpy(val + currentvalpos, (uint8_t *)label, llen);
currentvalpos += llen;
memcpy(val + currentvalpos, s->s3->client_random, SSL3_RANDOM_SIZE);
currentvalpos += SSL3_RANDOM_SIZE;
memcpy(val + currentvalpos, s->s3->server_random, SSL3_RANDOM_SIZE);
currentvalpos += SSL3_RANDOM_SIZE;
if (use_context) {
val[currentvalpos] = (contextlen >> 8) & 0xff;
currentvalpos++;
val[currentvalpos] = contextlen & 0xff;
currentvalpos++;
if (contextlen > 0 || context != NULL) {
memcpy(val + currentvalpos, context, contextlen);
}
}
/* disallow prohibited labels note that SSL3_RANDOM_SIZE > max(prohibited
* label len) = 15, so size of val > max(prohibited label len) = 15 and the
* comparisons won't have buffer overflow. */
if (memcmp(val, TLS_MD_CLIENT_FINISH_CONST,
TLS_MD_CLIENT_FINISH_CONST_SIZE) == 0 ||
memcmp(val, TLS_MD_SERVER_FINISH_CONST,
TLS_MD_SERVER_FINISH_CONST_SIZE) == 0 ||
memcmp(val, TLS_MD_MASTER_SECRET_CONST,
TLS_MD_MASTER_SECRET_CONST_SIZE) == 0 ||
memcmp(val, TLS_MD_KEY_EXPANSION_CONST,
TLS_MD_KEY_EXPANSION_CONST_SIZE) == 0) {
goto err1;
}
ret = tls1_PRF(ssl_get_algorithm2(s), val, vallen, NULL, 0, NULL, 0,
s->session->master_key, s->session->master_key_length, out,
buff, olen);
goto out;
err1:
OPENSSL_PUT_ERROR(SSL, tls1_export_keying_material,
SSL_R_TLS_ILLEGAL_EXPORTER_LABEL);
ret = 0;
goto out;
err2:
OPENSSL_PUT_ERROR(SSL, tls1_export_keying_material, ERR_R_MALLOC_FAILURE);
ret = 0;
out:
if (buff != NULL) {
OPENSSL_free(buff);
}
if (val != NULL) {
OPENSSL_free(val);
}
return ret;
}
int tls1_alert_code(int code) {
switch (code) {
case SSL_AD_CLOSE_NOTIFY:
return SSL3_AD_CLOSE_NOTIFY;
case SSL_AD_UNEXPECTED_MESSAGE:
return SSL3_AD_UNEXPECTED_MESSAGE;
case SSL_AD_BAD_RECORD_MAC:
return SSL3_AD_BAD_RECORD_MAC;
case SSL_AD_DECRYPTION_FAILED:
return TLS1_AD_DECRYPTION_FAILED;
case SSL_AD_RECORD_OVERFLOW:
return TLS1_AD_RECORD_OVERFLOW;
case SSL_AD_DECOMPRESSION_FAILURE:
return SSL3_AD_DECOMPRESSION_FAILURE;
case SSL_AD_HANDSHAKE_FAILURE:
return SSL3_AD_HANDSHAKE_FAILURE;
case SSL_AD_NO_CERTIFICATE:
return -1;
case SSL_AD_BAD_CERTIFICATE:
return SSL3_AD_BAD_CERTIFICATE;
case SSL_AD_UNSUPPORTED_CERTIFICATE:
return SSL3_AD_UNSUPPORTED_CERTIFICATE;
case SSL_AD_CERTIFICATE_REVOKED:
return SSL3_AD_CERTIFICATE_REVOKED;
case SSL_AD_CERTIFICATE_EXPIRED:
return SSL3_AD_CERTIFICATE_EXPIRED;
case SSL_AD_CERTIFICATE_UNKNOWN:
return SSL3_AD_CERTIFICATE_UNKNOWN;
case SSL_AD_ILLEGAL_PARAMETER:
return SSL3_AD_ILLEGAL_PARAMETER;
case SSL_AD_UNKNOWN_CA:
return TLS1_AD_UNKNOWN_CA;
case SSL_AD_ACCESS_DENIED:
return TLS1_AD_ACCESS_DENIED;
case SSL_AD_DECODE_ERROR:
return TLS1_AD_DECODE_ERROR;
case SSL_AD_DECRYPT_ERROR:
return TLS1_AD_DECRYPT_ERROR;
case SSL_AD_EXPORT_RESTRICTION:
return TLS1_AD_EXPORT_RESTRICTION;
case SSL_AD_PROTOCOL_VERSION:
return TLS1_AD_PROTOCOL_VERSION;
case SSL_AD_INSUFFICIENT_SECURITY:
return TLS1_AD_INSUFFICIENT_SECURITY;
case SSL_AD_INTERNAL_ERROR:
return TLS1_AD_INTERNAL_ERROR;
case SSL_AD_USER_CANCELLED:
return TLS1_AD_USER_CANCELLED;
case SSL_AD_NO_RENEGOTIATION:
return TLS1_AD_NO_RENEGOTIATION;
case SSL_AD_UNSUPPORTED_EXTENSION:
return TLS1_AD_UNSUPPORTED_EXTENSION;
case SSL_AD_CERTIFICATE_UNOBTAINABLE:
return TLS1_AD_CERTIFICATE_UNOBTAINABLE;
case SSL_AD_UNRECOGNIZED_NAME:
return TLS1_AD_UNRECOGNIZED_NAME;
case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
return TLS1_AD_BAD_CERTIFICATE_STATUS_RESPONSE;
case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
return TLS1_AD_BAD_CERTIFICATE_HASH_VALUE;
case SSL_AD_UNKNOWN_PSK_IDENTITY:
return TLS1_AD_UNKNOWN_PSK_IDENTITY;
case SSL_AD_INAPPROPRIATE_FALLBACK:
return SSL3_AD_INAPPROPRIATE_FALLBACK;
default:
return -1;
}
}
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