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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 <openssl/mem.h>
-
- #include "internal.h"
- #include "../crypto/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;
-
- /* kMaxEarlyDataSkipped is the maximum number of rejected early data bytes that
- * will be skipped. Without this limit an attacker could send records at a
- * faster rate than we can process and cause trial decryption to loop forever.
- * This value should be slightly above kMaxEarlyDataAccepted in tls13_server.c,
- * which is measured in plaintext. */
- static const size_t kMaxEarlyDataSkipped = 16384;
-
- /* kMaxWarningAlerts is the number of consecutive warning alerts that will be
- * processed. */
- static const uint8_t kMaxWarningAlerts = 4;
-
- /* 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);
- }
-
- static int ssl_uses_short_header(const SSL *ssl,
- enum evp_aead_direction_t dir) {
- if (!ssl->s3->short_header) {
- return 0;
- }
-
- if (dir == evp_aead_open) {
- return ssl->s3->aead_read_ctx != NULL;
- }
-
- return ssl->s3->aead_write_ctx != NULL;
- }
-
- int ssl_record_sequence_update(uint8_t *seq, size_t seq_len) {
- for (size_t 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) {
- size_t header_len;
- if (SSL_is_dtls(ssl)) {
- header_len = DTLS1_RT_HEADER_LENGTH;
- } else if (ssl_uses_short_header(ssl, evp_aead_open)) {
- header_len = 2;
- } else {
- header_len = SSL3_RT_HEADER_LENGTH;
- }
-
- return header_len + SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_read_ctx);
- }
-
- size_t ssl_seal_align_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);
- }
-
- size_t header_len;
- if (ssl_uses_short_header(ssl, evp_aead_seal)) {
- header_len = 2;
- } else {
- header_len = SSL3_RT_HEADER_LENGTH;
- }
-
- size_t ret =
- header_len + SSL_AEAD_CTX_explicit_nonce_len(ssl->s3->aead_write_ctx);
- if (ssl_needs_record_splitting(ssl)) {
- ret += header_len;
- 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 dtls_max_seal_overhead(ssl, dtls1_use_current_epoch);
- }
-
- size_t ret =
- ssl_uses_short_header(ssl, evp_aead_seal) ? 2 : SSL3_RT_HEADER_LENGTH;
- ret += SSL_AEAD_CTX_max_overhead(ssl->s3->aead_write_ctx);
- /* TLS 1.3 needs an extra byte for the encrypted record type. */
- if (ssl->s3->have_version &&
- ssl3_protocol_version(ssl) >= TLS1_3_VERSION) {
- ret += 1;
- }
- if (ssl_needs_record_splitting(ssl)) {
- ret *= 2;
- }
- return ret;
- }
-
- enum ssl_open_record_t tls_open_record(SSL *ssl, uint8_t *out_type, CBS *out,
- size_t *out_consumed, uint8_t *out_alert,
- uint8_t *in, size_t in_len) {
- *out_consumed = 0;
-
- CBS cbs;
- CBS_init(&cbs, in, in_len);
-
- /* Decode the record header. */
- uint8_t type;
- uint16_t version, ciphertext_len;
- size_t header_len;
- if (ssl_uses_short_header(ssl, evp_aead_open)) {
- if (!CBS_get_u16(&cbs, &ciphertext_len)) {
- *out_consumed = 2;
- return ssl_open_record_partial;
- }
-
- if ((ciphertext_len & 0x8000) == 0) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
- *out_alert = SSL_AD_DECODE_ERROR;
- return ssl_open_record_error;
- }
-
- ciphertext_len &= 0x7fff;
- type = SSL3_RT_APPLICATION_DATA;
- version = TLS1_VERSION;
- header_len = 2;
- } else {
- 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;
- }
- header_len = SSL3_RT_HEADER_LENGTH;
- }
-
- int version_ok;
- if (ssl->s3->aead_read_ctx == NULL) {
- /* Only check the first byte. Enforcing beyond that can prevent decoding
- * version negotiation failure alerts. */
- version_ok = (version >> 8) == SSL3_VERSION_MAJOR;
- } else if (ssl3_protocol_version(ssl) < TLS1_3_VERSION) {
- /* Earlier versions of TLS switch the record version. */
- version_ok = version == ssl->version;
- } else {
- /* Starting TLS 1.3, the version field is frozen at {3, 1}. */
- version_ok = version == TLS1_VERSION;
- }
-
- if (!version_ok) {
- 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 = header_len + (size_t)ciphertext_len;
- return ssl_open_record_partial;
- }
-
- ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HEADER, in, header_len);
-
- *out_consumed = in_len - CBS_len(&cbs);
-
- /* Skip early data received when expecting a second ClientHello if we rejected
- * 0RTT. */
- if (ssl->s3->skip_early_data &&
- ssl->s3->aead_read_ctx == NULL &&
- type == SSL3_RT_APPLICATION_DATA) {
- goto skipped_data;
- }
-
- /* Decrypt the body in-place. */
- if (!SSL_AEAD_CTX_open(ssl->s3->aead_read_ctx, out, type, version,
- ssl->s3->read_sequence, (uint8_t *)CBS_data(&body),
- CBS_len(&body))) {
- if (ssl->s3->skip_early_data &&
- ssl->s3->aead_read_ctx != NULL) {
- ERR_clear_error();
- goto skipped_data;
- }
-
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
- *out_alert = SSL_AD_BAD_RECORD_MAC;
- return ssl_open_record_error;
- }
-
- ssl->s3->skip_early_data = 0;
-
- if (!ssl_record_sequence_update(ssl->s3->read_sequence, 8)) {
- *out_alert = SSL_AD_INTERNAL_ERROR;
- return ssl_open_record_error;
- }
-
- /* TLS 1.3 hides the record type inside the encrypted data. */
- if (ssl->s3->have_version &&
- ssl3_protocol_version(ssl) >= TLS1_3_VERSION &&
- ssl->s3->aead_read_ctx != NULL) {
- /* The outer record type is always application_data. */
- if (type != SSL3_RT_APPLICATION_DATA) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_OUTER_RECORD_TYPE);
- *out_alert = SSL_AD_DECODE_ERROR;
- return ssl_open_record_error;
- }
-
- do {
- if (!CBS_get_last_u8(out, &type)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
- *out_alert = SSL_AD_DECRYPT_ERROR;
- return ssl_open_record_error;
- }
- } while (type == 0);
- }
-
- /* Check the plaintext length. */
- if (CBS_len(out) > 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 (CBS_len(out) == 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;
- }
-
- if (type == SSL3_RT_ALERT) {
- return ssl_process_alert(ssl, out_alert, CBS_data(out), CBS_len(out));
- }
-
- ssl->s3->warning_alert_count = 0;
-
- *out_type = type;
- return ssl_open_record_success;
-
- skipped_data:
- ssl->s3->early_data_skipped += *out_consumed;
- if (ssl->s3->early_data_skipped < *out_consumed) {
- ssl->s3->early_data_skipped = kMaxEarlyDataSkipped + 1;
- }
-
- if (ssl->s3->early_data_skipped > kMaxEarlyDataSkipped) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MUCH_SKIPPED_EARLY_DATA);
- *out_alert = SSL_AD_UNEXPECTED_MESSAGE;
- return ssl_open_record_error;
- }
-
- return ssl_open_record_discard;
- }
-
- 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) {
- assert(!buffers_alias(in, in_len, out, max_out));
-
- const int short_header = ssl_uses_short_header(ssl, evp_aead_seal);
- size_t header_len = short_header ? 2 : SSL3_RT_HEADER_LENGTH;
-
- /* TLS 1.3 hides the actual record type inside the encrypted data. */
- if (ssl->s3->have_version &&
- ssl3_protocol_version(ssl) >= TLS1_3_VERSION &&
- ssl->s3->aead_write_ctx != NULL) {
- if (in_len > in_len + header_len + 1 || max_out < in_len + header_len + 1) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
- return 0;
- }
-
- OPENSSL_memcpy(out + header_len, in, in_len);
- out[header_len + in_len] = type;
- in = out + header_len;
- type = SSL3_RT_APPLICATION_DATA;
- in_len++;
- }
-
- if (max_out < header_len) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_BUFFER_TOO_SMALL);
- return 0;
- }
-
- /* The TLS record-layer version number is meaningless and, starting in
- * TLS 1.3, is frozen at TLS 1.0. But for historical reasons, SSL 3.0
- * ClientHellos should use SSL 3.0 and pre-TLS-1.3 expects the version
- * to change after version negotiation. */
- uint16_t wire_version = TLS1_VERSION;
- if (ssl->version == SSL3_VERSION ||
- (ssl->s3->have_version && ssl3_protocol_version(ssl) < TLS1_3_VERSION)) {
- wire_version = ssl->version;
- }
-
- /* Write the non-length portions of the header. */
- if (!short_header) {
- out[0] = type;
- out[1] = wire_version >> 8;
- out[2] = wire_version & 0xff;
- out += 3;
- max_out -= 3;
- }
-
- /* Write the ciphertext, leaving two bytes for the length. */
- size_t ciphertext_len;
- if (!SSL_AEAD_CTX_seal(ssl->s3->aead_write_ctx, out + 2, &ciphertext_len,
- max_out - 2, type, wire_version,
- ssl->s3->write_sequence, in, in_len) ||
- !ssl_record_sequence_update(ssl->s3->write_sequence, 8)) {
- return 0;
- }
-
- /* Fill in the length. */
- if (ciphertext_len >= 1 << 15) {
- OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
- return 0;
- }
- out[0] = ciphertext_len >> 8;
- out[1] = ciphertext_len & 0xff;
- if (short_header) {
- out[0] |= 0x80;
- }
-
- *out_len = header_len + ciphertext_len;
-
- ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_HEADER, out, header_len);
- 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) {
- if (buffers_alias(in, in_len, out, max_out)) {
- OPENSSL_PUT_ERROR(SSL, SSL_R_OUTPUT_ALIASES_INPUT);
- return 0;
- }
-
- size_t frag_len = 0;
- if (type == SSL3_RT_APPLICATION_DATA && in_len > 1 &&
- ssl_needs_record_splitting(ssl)) {
- if (!do_seal_record(ssl, out, &frag_len, max_out, type, in, 1)) {
- return 0;
- }
- in++;
- in_len--;
- out += frag_len;
- max_out -= frag_len;
-
- assert(!ssl_uses_short_header(ssl, evp_aead_seal));
- #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;
- }
-
- enum ssl_open_record_t ssl_process_alert(SSL *ssl, uint8_t *out_alert,
- const uint8_t *in, size_t in_len) {
- /* Alerts records may not contain fragmented or multiple alerts. */
- if (in_len != 2) {
- *out_alert = SSL_AD_DECODE_ERROR;
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ALERT);
- return ssl_open_record_error;
- }
-
- ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_ALERT, in, in_len);
-
- const uint8_t alert_level = in[0];
- const uint8_t alert_descr = in[1];
-
- uint16_t alert = (alert_level << 8) | alert_descr;
- ssl_do_info_callback(ssl, SSL_CB_READ_ALERT, alert);
-
- if (alert_level == SSL3_AL_WARNING) {
- if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
- ssl->s3->recv_shutdown = ssl_shutdown_close_notify;
- return ssl_open_record_close_notify;
- }
-
- /* Warning alerts do not exist in TLS 1.3. */
- if (ssl->s3->have_version &&
- ssl3_protocol_version(ssl) >= TLS1_3_VERSION) {
- *out_alert = SSL_AD_DECODE_ERROR;
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ALERT);
- return ssl_open_record_error;
- }
-
- ssl->s3->warning_alert_count++;
- if (ssl->s3->warning_alert_count > kMaxWarningAlerts) {
- *out_alert = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_WARNING_ALERTS);
- return ssl_open_record_error;
- }
- return ssl_open_record_discard;
- }
-
- if (alert_level == SSL3_AL_FATAL) {
- ssl->s3->recv_shutdown = ssl_shutdown_fatal_alert;
-
- char tmp[16];
- OPENSSL_PUT_ERROR(SSL, SSL_AD_REASON_OFFSET + alert_descr);
- BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr);
- ERR_add_error_data(2, "SSL alert number ", tmp);
- return ssl_open_record_fatal_alert;
- }
-
- *out_alert = SSL_AD_ILLEGAL_PARAMETER;
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_ALERT_TYPE);
- return ssl_open_record_error;
- }
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