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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) 1998-2002 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). */
#include <openssl/ssl.h>
#include <assert.h>
#include <string.h>
#include <openssl/bytestring.h>
#include <openssl/err.h>
#include "internal.h"
/* kMaxEmptyRecords is the number of consecutive, empty records that will be
* processed. Without this limit an attacker could send empty records at a
* faster rate than we can process and cause record processing to loop
* forever. */
static const uint8_t kMaxEmptyRecords = 32;
/* ssl_needs_record_splitting returns one if |ssl|'s current outgoing cipher
* state needs record-splitting and zero otherwise. */
static int ssl_needs_record_splitting(const SSL *ssl) {
return ssl->s3->aead_write_ctx != NULL &&
ssl3_protocol_version(ssl) < TLS1_1_VERSION &&
(ssl->mode & SSL_MODE_CBC_RECORD_SPLITTING) != 0 &&
SSL_CIPHER_is_block_cipher(ssl->s3->aead_write_ctx->cipher);
}
int ssl_record_sequence_update(uint8_t *seq, size_t seq_len) {
size_t i;
for (i = seq_len - 1; i < seq_len; i--) {
++seq[i];
if (seq[i] != 0) {
return 1;
}
}
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return 0;
}
size_t ssl_record_prefix_len(const SSL *ssl) {
if (SSL_IS_DTLS(ssl)) {
return DTLS1_RT_HEADER_LENGTH +
SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_read_ctx);
} else {
return SSL3_RT_HEADER_LENGTH +
SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_read_ctx);
}
}
size_t ssl_seal_prefix_len(const SSL *ssl) {
if (SSL_IS_DTLS(ssl)) {
return DTLS1_RT_HEADER_LENGTH +
SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_write_ctx);
} else {
size_t ret = SSL3_RT_HEADER_LENGTH +
SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_write_ctx);
if (ssl_needs_record_splitting(ssl)) {
ret += SSL3_RT_HEADER_LENGTH;
ret += ssl_cipher_get_record_split_len(ssl->s3->aead_write_ctx->cipher);
}
return ret;
}
}
size_t ssl_max_seal_overhead(const SSL *ssl) {
if (SSL_IS_DTLS(ssl)) {
return DTLS1_RT_HEADER_LENGTH +
SSL_AEAD_CTX_max_overhead(ssl->s3->aead_write_ctx);
} else {
size_t ret = SSL3_RT_HEADER_LENGTH +
SSL_AEAD_CTX_max_overhead(ssl->s3->aead_write_ctx);
if (ssl_needs_record_splitting(ssl)) {
ret *= 2;
}
return ret;
}
}
enum ssl_open_record_t tls_open_record(
SSL *ssl, uint8_t *out_type, uint8_t *out, size_t *out_len,
size_t *out_consumed, uint8_t *out_alert, size_t max_out, const uint8_t *in,
size_t in_len) {
CBS cbs;
CBS_init(&cbs, in, in_len);
/* Decode the record header. */
uint8_t type;
uint16_t version, ciphertext_len;
if (!CBS_get_u8(&cbs, &type) ||
!CBS_get_u16(&cbs, &version) ||
!CBS_get_u16(&cbs, &ciphertext_len)) {
*out_consumed = SSL3_RT_HEADER_LENGTH;
return ssl_open_record_partial;
}
/* Check the version. */
if ((ssl->s3->have_version && version != ssl->version) ||
(version >> 8) != SSL3_VERSION_MAJOR) {
OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER);
*out_alert = SSL_AD_PROTOCOL_VERSION;
return ssl_open_record_error;
}
/* Check the ciphertext length. */
if (ciphertext_len > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
OPENSSL_PUT_ERROR(SSL, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
*out_alert = SSL_AD_RECORD_OVERFLOW;
return ssl_open_record_error;
}
/* Extract the body. */
CBS body;
if (!CBS_get_bytes(&cbs, &body, ciphertext_len)) {
*out_consumed = SSL3_RT_HEADER_LENGTH + (size_t)ciphertext_len;
return ssl_open_record_partial;
}
if (ssl->msg_callback != NULL) {
ssl->msg_callback(0 /* read */, 0, SSL3_RT_HEADER, in,
SSL3_RT_HEADER_LENGTH, ssl, ssl->msg_callback_arg);
}
/* Decrypt the body. */
size_t plaintext_len;
if (!SSL_AEAD_CTX_open(ssl->s3->aead_read_ctx, out, &plaintext_len, max_out,
type, version, ssl->s3->read_sequence, CBS_data(&body),
CBS_len(&body))) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
*out_alert = SSL_AD_BAD_RECORD_MAC;
return ssl_open_record_error;
}
if (!ssl_record_sequence_update(ssl->s3->read_sequence, 8)) {
*out_alert = SSL_AD_INTERNAL_ERROR;
return ssl_open_record_error;
}
/* Check the plaintext length. */
if (plaintext_len > SSL3_RT_MAX_PLAIN_LENGTH) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG);
*out_alert = SSL_AD_RECORD_OVERFLOW;
return ssl_open_record_error;
}
/* Limit the number of consecutive empty records. */
if (plaintext_len == 0) {
ssl->s3->empty_record_count++;
if (ssl->s3->empty_record_count > kMaxEmptyRecords) {
OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_EMPTY_FRAGMENTS);
*out_alert = SSL_AD_UNEXPECTED_MESSAGE;
return ssl_open_record_error;
}
/* Apart from the limit, empty records are returned up to the caller. This
* allows the caller to reject records of the wrong type. */
} else {
ssl->s3->empty_record_count = 0;
}
*out_type = type;
*out_len = plaintext_len;
*out_consumed = in_len - CBS_len(&cbs);
return ssl_open_record_success;
}
static int do_seal_record(SSL *ssl, uint8_t *out, size_t *out_len,
size_t max_out, uint8_t type, const uint8_t *in,
size_t in_len) {
if (max_out < SSL3_RT_HEADER_LENGTH) {
OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
return 0;
}
/* Check the record header does not alias any part of the input.
* |SSL_AEAD_CTX_seal| will internally enforce other aliasing requirements. */
if (in < out + SSL3_RT_HEADER_LENGTH && out < in + in_len) {
OPENSSL_PUT_ERROR(SSL, SSL_R_OUTPUT_ALIASES_INPUT);
return 0;
}
out[0] = type;
/* Some servers hang if initial ClientHello is larger than 256 bytes and
* record version number > TLS 1.0. */
uint16_t wire_version = ssl->version;
if (!ssl->s3->have_version && ssl->version > SSL3_VERSION) {
wire_version = TLS1_VERSION;
}
out[1] = wire_version >> 8;
out[2] = wire_version & 0xff;
size_t ciphertext_len;
if (!SSL_AEAD_CTX_seal(ssl->s3->aead_write_ctx, out + SSL3_RT_HEADER_LENGTH,
&ciphertext_len, max_out - SSL3_RT_HEADER_LENGTH,
type, wire_version, ssl->s3->write_sequence, in,
in_len) ||
!ssl_record_sequence_update(ssl->s3->write_sequence, 8)) {
return 0;
}
if (ciphertext_len >= 1 << 16) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return 0;
}
out[3] = ciphertext_len >> 8;
out[4] = ciphertext_len & 0xff;
*out_len = SSL3_RT_HEADER_LENGTH + ciphertext_len;
if (ssl->msg_callback) {
ssl->msg_callback(1 /* write */, 0, SSL3_RT_HEADER, out,
SSL3_RT_HEADER_LENGTH, ssl, ssl->msg_callback_arg);
}
return 1;
}
int tls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
uint8_t type, const uint8_t *in, size_t in_len) {
size_t frag_len = 0;
if (type == SSL3_RT_APPLICATION_DATA && in_len > 1 &&
ssl_needs_record_splitting(ssl)) {
/* |do_seal_record| will notice if it clobbers |in[0]|, but not if it
* aliases the rest of |in|. */
if (in + 1 <= out && out < in + in_len) {
OPENSSL_PUT_ERROR(SSL, SSL_R_OUTPUT_ALIASES_INPUT);
return 0;
}
/* Ensure |do_seal_record| does not write beyond |in[0]|. */
size_t frag_max_out = max_out;
if (out <= in + 1 && in + 1 < out + frag_max_out) {
frag_max_out = (size_t)(in + 1 - out);
}
if (!do_seal_record(ssl, out, &frag_len, frag_max_out, type, in, 1)) {
return 0;
}
in++;
in_len--;
out += frag_len;
max_out -= frag_len;
#if !defined(BORINGSSL_UNSAFE_FUZZER_MODE)
assert(SSL3_RT_HEADER_LENGTH + ssl_cipher_get_record_split_len(
ssl->s3->aead_write_ctx->cipher) ==
frag_len);
#endif
}
if (!do_seal_record(ssl, out, out_len, max_out, type, in, in_len)) {
return 0;
}
*out_len += frag_len;
return 1;
}
void ssl_set_read_state(SSL *ssl, SSL_AEAD_CTX *aead_ctx) {
if (SSL_IS_DTLS(ssl)) {
ssl->d1->r_epoch++;
memset(&ssl->d1->bitmap, 0, sizeof(ssl->d1->bitmap));
}
memset(ssl->s3->read_sequence, 0, sizeof(ssl->s3->read_sequence));
SSL_AEAD_CTX_free(ssl->s3->aead_read_ctx);
ssl->s3->aead_read_ctx = aead_ctx;
}
void ssl_set_write_state(SSL *ssl, SSL_AEAD_CTX *aead_ctx) {
if (SSL_IS_DTLS(ssl)) {
ssl->d1->w_epoch++;
memcpy(ssl->d1->last_write_sequence, ssl->s3->write_sequence,
sizeof(ssl->s3->write_sequence));
}
memset(ssl->s3->write_sequence, 0, sizeof(ssl->s3->write_sequence));
SSL_AEAD_CTX_free(ssl->s3->aead_write_ctx);
ssl->s3->aead_write_ctx = aead_ctx;
}