/* 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 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. * * Portions of the attached software ("Contribution") are developed by * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. * * The Contribution is licensed pursuant to the OpenSSL open source * license provided above. * * ECC cipher suite support in OpenSSL originally written by * Vipul Gupta and Sumit Gupta of Sun Microsystems Laboratories. * */ /* ==================================================================== * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "internal.h" #include "../crypto/internal.h" #include "../crypto/dh/internal.h" int ssl3_accept(SSL *ssl) { BUF_MEM *buf = NULL; uint32_t alg_a; int ret = -1; int state, skip = 0; assert(ssl->handshake_func == ssl3_accept); assert(ssl->server); assert(!SSL_IS_DTLS(ssl)); for (;;) { state = ssl->state; switch (ssl->state) { case SSL_ST_ACCEPT: ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_START, 1); if (ssl->init_buf == NULL) { buf = BUF_MEM_new(); if (!buf || !BUF_MEM_reserve(buf, SSL3_RT_MAX_PLAIN_LENGTH)) { ret = -1; goto end; } ssl->init_buf = buf; buf = NULL; } ssl->init_num = 0; /* Enable a write buffer. This groups handshake messages within a flight * into a single write. */ if (!ssl_init_wbio_buffer(ssl)) { ret = -1; goto end; } if (!ssl3_init_handshake_buffer(ssl)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); ret = -1; goto end; } if (!ssl->s3->have_version) { ssl->state = SSL3_ST_SR_INITIAL_BYTES; } else { ssl->state = SSL3_ST_SR_CLNT_HELLO_A; } break; case SSL3_ST_SR_INITIAL_BYTES: ret = ssl3_get_initial_bytes(ssl); if (ret <= 0) { goto end; } /* ssl3_get_initial_bytes sets ssl->state to one of * SSL3_ST_SR_V2_CLIENT_HELLO or SSL3_ST_SR_CLNT_HELLO_A on success. */ break; case SSL3_ST_SR_V2_CLIENT_HELLO: ret = ssl3_get_v2_client_hello(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SR_CLNT_HELLO_A; break; case SSL3_ST_SR_CLNT_HELLO_A: case SSL3_ST_SR_CLNT_HELLO_B: case SSL3_ST_SR_CLNT_HELLO_C: ret = ssl3_get_client_hello(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SW_SRVR_HELLO_A; break; case SSL3_ST_SW_SRVR_HELLO_A: case SSL3_ST_SW_SRVR_HELLO_B: ret = ssl3_send_server_hello(ssl); if (ret <= 0) { goto end; } if (ssl->hit) { if (ssl->tlsext_ticket_expected) { ssl->state = SSL3_ST_SW_SESSION_TICKET_A; } else { ssl->state = SSL3_ST_SW_CHANGE_A; } } else { ssl->state = SSL3_ST_SW_CERT_A; } break; case SSL3_ST_SW_CERT_A: case SSL3_ST_SW_CERT_B: if (ssl_cipher_uses_certificate_auth(ssl->s3->tmp.new_cipher)) { ret = ssl3_send_server_certificate(ssl); if (ret <= 0) { goto end; } if (ssl->s3->tmp.certificate_status_expected) { ssl->state = SSL3_ST_SW_CERT_STATUS_A; } else { ssl->state = SSL3_ST_SW_KEY_EXCH_A; } } else { skip = 1; ssl->state = SSL3_ST_SW_KEY_EXCH_A; } break; case SSL3_ST_SW_CERT_STATUS_A: case SSL3_ST_SW_CERT_STATUS_B: ret = ssl3_send_certificate_status(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SW_KEY_EXCH_A; break; case SSL3_ST_SW_KEY_EXCH_A: case SSL3_ST_SW_KEY_EXCH_B: case SSL3_ST_SW_KEY_EXCH_C: alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; /* Send a ServerKeyExchange message if: * - The key exchange is ephemeral or anonymous * Diffie-Hellman. * - There is a PSK identity hint. * * TODO(davidben): This logic is currently duplicated in d1_srvr.c. Fix * this. In the meantime, keep them in sync. */ if (ssl_cipher_requires_server_key_exchange(ssl->s3->tmp.new_cipher) || ((alg_a & SSL_aPSK) && ssl->psk_identity_hint)) { ret = ssl3_send_server_key_exchange(ssl); if (ret <= 0) { goto end; } } else { skip = 1; } ssl->state = SSL3_ST_SW_CERT_REQ_A; break; case SSL3_ST_SW_CERT_REQ_A: case SSL3_ST_SW_CERT_REQ_B: if (ssl->s3->tmp.cert_request) { ret = ssl3_send_certificate_request(ssl); if (ret <= 0) { goto end; } } else { skip = 1; } ssl->state = SSL3_ST_SW_SRVR_DONE_A; break; case SSL3_ST_SW_SRVR_DONE_A: case SSL3_ST_SW_SRVR_DONE_B: ret = ssl3_send_server_done(ssl); if (ret <= 0) { goto end; } ssl->s3->tmp.next_state = SSL3_ST_SR_CERT_A; ssl->state = SSL3_ST_SW_FLUSH; break; case SSL3_ST_SW_FLUSH: /* This code originally checked to see if any data was pending using * BIO_CTRL_INFO and then flushed. This caused problems as documented * in PR#1939. The proposed fix doesn't completely resolve this issue * as buggy implementations of BIO_CTRL_PENDING still exist. So instead * we just flush unconditionally. */ if (BIO_flush(ssl->wbio) <= 0) { ssl->rwstate = SSL_WRITING; ret = -1; goto end; } ssl->state = ssl->s3->tmp.next_state; break; case SSL3_ST_SR_CERT_A: if (ssl->s3->tmp.cert_request) { ret = ssl3_get_client_certificate(ssl); if (ret <= 0) { goto end; } } ssl->state = SSL3_ST_SR_KEY_EXCH_A; break; case SSL3_ST_SR_KEY_EXCH_A: case SSL3_ST_SR_KEY_EXCH_B: ret = ssl3_get_client_key_exchange(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SR_CERT_VRFY_A; break; case SSL3_ST_SR_CERT_VRFY_A: ret = ssl3_get_cert_verify(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SR_CHANGE; break; case SSL3_ST_SR_CHANGE: ret = ssl->method->ssl_read_change_cipher_spec(ssl); if (ret <= 0) { goto end; } if (!tls1_change_cipher_state(ssl, SSL3_CHANGE_CIPHER_SERVER_READ)) { ret = -1; goto end; } if (ssl->s3->next_proto_neg_seen) { ssl->state = SSL3_ST_SR_NEXT_PROTO_A; } else if (ssl->s3->tlsext_channel_id_valid) { ssl->state = SSL3_ST_SR_CHANNEL_ID_A; } else { ssl->state = SSL3_ST_SR_FINISHED_A; } break; case SSL3_ST_SR_NEXT_PROTO_A: ret = ssl3_get_next_proto(ssl); if (ret <= 0) { goto end; } if (ssl->s3->tlsext_channel_id_valid) { ssl->state = SSL3_ST_SR_CHANNEL_ID_A; } else { ssl->state = SSL3_ST_SR_FINISHED_A; } break; case SSL3_ST_SR_CHANNEL_ID_A: ret = ssl3_get_channel_id(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SR_FINISHED_A; break; case SSL3_ST_SR_FINISHED_A: ret = ssl3_get_finished(ssl); if (ret <= 0) { goto end; } if (ssl->hit) { ssl->state = SSL_ST_OK; } else if (ssl->tlsext_ticket_expected) { ssl->state = SSL3_ST_SW_SESSION_TICKET_A; } else { ssl->state = SSL3_ST_SW_CHANGE_A; } /* If this is a full handshake with ChannelID then record the hashshake * hashes in |ssl->session| in case we need them to verify a ChannelID * signature on a resumption of this session in the future. */ if (!ssl->hit && ssl->s3->tlsext_channel_id_valid) { ret = tls1_record_handshake_hashes_for_channel_id(ssl); if (ret <= 0) { goto end; } } break; case SSL3_ST_SW_SESSION_TICKET_A: case SSL3_ST_SW_SESSION_TICKET_B: ret = ssl3_send_new_session_ticket(ssl); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SW_CHANGE_A; break; case SSL3_ST_SW_CHANGE_A: case SSL3_ST_SW_CHANGE_B: ret = ssl3_send_change_cipher_spec(ssl, SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SW_FINISHED_A; if (!tls1_change_cipher_state(ssl, SSL3_CHANGE_CIPHER_SERVER_WRITE)) { ret = -1; goto end; } break; case SSL3_ST_SW_FINISHED_A: case SSL3_ST_SW_FINISHED_B: ret = ssl3_send_finished(ssl, SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B); if (ret <= 0) { goto end; } ssl->state = SSL3_ST_SW_FLUSH; if (ssl->hit) { ssl->s3->tmp.next_state = SSL3_ST_SR_CHANGE; } else { ssl->s3->tmp.next_state = SSL_ST_OK; } break; case SSL_ST_OK: /* clean a few things up */ ssl3_cleanup_key_block(ssl); BUF_MEM_free(ssl->init_buf); ssl->init_buf = NULL; ssl->init_num = 0; /* remove buffering on output */ ssl_free_wbio_buffer(ssl); /* If we aren't retaining peer certificates then we can discard it * now. */ if (ssl->ctx->retain_only_sha256_of_client_certs) { X509_free(ssl->session->peer); ssl->session->peer = NULL; sk_X509_pop_free(ssl->session->cert_chain, X509_free); ssl->session->cert_chain = NULL; } ssl->s3->initial_handshake_complete = 1; ssl_update_cache(ssl, SSL_SESS_CACHE_SERVER); ssl_do_info_callback(ssl, SSL_CB_HANDSHAKE_DONE, 1); ret = 1; goto end; default: OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); ret = -1; goto end; } if (!ssl->s3->tmp.reuse_message && !skip && ssl->state != state) { int new_state = ssl->state; ssl->state = state; ssl_do_info_callback(ssl, SSL_CB_ACCEPT_LOOP, 1); ssl->state = new_state; } skip = 0; } end: BUF_MEM_free(buf); ssl_do_info_callback(ssl, SSL_CB_ACCEPT_EXIT, ret); return ret; } int ssl3_get_initial_bytes(SSL *ssl) { /* Read the first 5 bytes, the size of the TLS record header. This is * sufficient to detect a V2ClientHello and ensures that we never read beyond * the first record. */ int ret = ssl_read_buffer_extend_to(ssl, SSL3_RT_HEADER_LENGTH); if (ret <= 0) { return ret; } assert(ssl_read_buffer_len(ssl) == SSL3_RT_HEADER_LENGTH); const uint8_t *p = ssl_read_buffer(ssl); /* Some dedicated error codes for protocol mixups should the application wish * to interpret them differently. (These do not overlap with ClientHello or * V2ClientHello.) */ if (strncmp("GET ", (const char *)p, 4) == 0 || strncmp("POST ", (const char *)p, 5) == 0 || strncmp("HEAD ", (const char *)p, 5) == 0 || strncmp("PUT ", (const char *)p, 4) == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_HTTP_REQUEST); return -1; } if (strncmp("CONNE", (const char *)p, 5) == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_HTTPS_PROXY_REQUEST); return -1; } /* Determine if this is a V2ClientHello. */ if ((p[0] & 0x80) && p[2] == SSL2_MT_CLIENT_HELLO && p[3] >= SSL3_VERSION_MAJOR) { /* This is a V2ClientHello. */ ssl->state = SSL3_ST_SR_V2_CLIENT_HELLO; return 1; } /* Fall through to the standard logic. */ ssl->state = SSL3_ST_SR_CLNT_HELLO_A; return 1; } int ssl3_get_v2_client_hello(SSL *ssl) { const uint8_t *p; int ret; CBS v2_client_hello, cipher_specs, session_id, challenge; size_t msg_length, rand_len; uint8_t msg_type; uint16_t version, cipher_spec_length, session_id_length, challenge_length; CBB client_hello, hello_body, cipher_suites; uint8_t random[SSL3_RANDOM_SIZE]; /* Determine the length of the V2ClientHello. */ assert(ssl_read_buffer_len(ssl) >= SSL3_RT_HEADER_LENGTH); p = ssl_read_buffer(ssl); msg_length = ((p[0] & 0x7f) << 8) | p[1]; if (msg_length > (1024 * 4)) { OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_TOO_LARGE); return -1; } if (msg_length < SSL3_RT_HEADER_LENGTH - 2) { /* Reject lengths that are too short early. We have already read * |SSL3_RT_HEADER_LENGTH| bytes, so we should not attempt to process an * (invalid) V2ClientHello which would be shorter than that. */ OPENSSL_PUT_ERROR(SSL, SSL_R_RECORD_LENGTH_MISMATCH); return -1; } /* Read the remainder of the V2ClientHello. */ ret = ssl_read_buffer_extend_to(ssl, 2 + msg_length); if (ret <= 0) { return ret; } assert(ssl_read_buffer_len(ssl) == msg_length + 2); CBS_init(&v2_client_hello, ssl_read_buffer(ssl) + 2, msg_length); /* The V2ClientHello without the length is incorporated into the handshake * hash. */ if (!ssl3_update_handshake_hash(ssl, CBS_data(&v2_client_hello), CBS_len(&v2_client_hello))) { return -1; } ssl_do_msg_callback(ssl, 0 /* read */, SSL2_VERSION, 0, CBS_data(&v2_client_hello), CBS_len(&v2_client_hello)); if (!CBS_get_u8(&v2_client_hello, &msg_type) || !CBS_get_u16(&v2_client_hello, &version) || !CBS_get_u16(&v2_client_hello, &cipher_spec_length) || !CBS_get_u16(&v2_client_hello, &session_id_length) || !CBS_get_u16(&v2_client_hello, &challenge_length) || !CBS_get_bytes(&v2_client_hello, &cipher_specs, cipher_spec_length) || !CBS_get_bytes(&v2_client_hello, &session_id, session_id_length) || !CBS_get_bytes(&v2_client_hello, &challenge, challenge_length) || CBS_len(&v2_client_hello) != 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } /* msg_type has already been checked. */ assert(msg_type == SSL2_MT_CLIENT_HELLO); /* The client_random is the V2ClientHello challenge. Truncate or * left-pad with zeros as needed. */ memset(random, 0, SSL3_RANDOM_SIZE); rand_len = CBS_len(&challenge); if (rand_len > SSL3_RANDOM_SIZE) { rand_len = SSL3_RANDOM_SIZE; } memcpy(random + (SSL3_RANDOM_SIZE - rand_len), CBS_data(&challenge), rand_len); /* Write out an equivalent SSLv3 ClientHello. */ CBB_zero(&client_hello); if (!CBB_init_fixed(&client_hello, (uint8_t *)ssl->init_buf->data, ssl->init_buf->max) || !CBB_add_u8(&client_hello, SSL3_MT_CLIENT_HELLO) || !CBB_add_u24_length_prefixed(&client_hello, &hello_body) || !CBB_add_u16(&hello_body, version) || !CBB_add_bytes(&hello_body, random, SSL3_RANDOM_SIZE) || /* No session id. */ !CBB_add_u8(&hello_body, 0) || !CBB_add_u16_length_prefixed(&hello_body, &cipher_suites)) { CBB_cleanup(&client_hello); OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); return -1; } /* Copy the cipher suites. */ while (CBS_len(&cipher_specs) > 0) { uint32_t cipher_spec; if (!CBS_get_u24(&cipher_specs, &cipher_spec)) { CBB_cleanup(&client_hello); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return -1; } /* Skip SSLv2 ciphers. */ if ((cipher_spec & 0xff0000) != 0) { continue; } if (!CBB_add_u16(&cipher_suites, cipher_spec)) { CBB_cleanup(&client_hello); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } } /* Add the null compression scheme and finish. */ if (!CBB_add_u8(&hello_body, 1) || !CBB_add_u8(&hello_body, 0) || !CBB_finish(&client_hello, NULL, &ssl->init_buf->length)) { CBB_cleanup(&client_hello); OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } /* Mark the message for "re"-use by the version-specific method. */ ssl->s3->tmp.reuse_message = 1; ssl->s3->tmp.message_type = SSL3_MT_CLIENT_HELLO; ssl->s3->tmp.message_complete = 1; /* Consume and discard the V2ClientHello. */ ssl_read_buffer_consume(ssl, 2 + msg_length); ssl_read_buffer_discard(ssl); return 1; } int ssl3_get_client_hello(SSL *ssl) { int ok, al = SSL_AD_INTERNAL_ERROR, ret = -1; long n; const SSL_CIPHER *c; STACK_OF(SSL_CIPHER) *ciphers = NULL; struct ssl_early_callback_ctx early_ctx; CBS client_hello; uint16_t client_version; CBS client_random, session_id, cipher_suites, compression_methods; SSL_SESSION *session = NULL; /* We do this so that we will respond with our native type. If we are TLSv1 * and we get SSLv3, we will respond with TLSv1, This down switching should * be handled by a different method. If we are SSLv3, we will respond with * SSLv3, even if prompted with TLSv1. */ switch (ssl->state) { case SSL3_ST_SR_CLNT_HELLO_A: n = ssl->method->ssl_get_message(ssl, SSL3_MT_CLIENT_HELLO, ssl_hash_message, &ok); if (!ok) { return n; } ssl->state = SSL3_ST_SR_CLNT_HELLO_B; /* fallthrough */ case SSL3_ST_SR_CLNT_HELLO_B: case SSL3_ST_SR_CLNT_HELLO_C: /* We have previously parsed the ClientHello message, and can't call * ssl_get_message again without hashing the message into the Finished * digest again. */ n = ssl->init_num; memset(&early_ctx, 0, sizeof(early_ctx)); early_ctx.ssl = ssl; early_ctx.client_hello = ssl->init_msg; early_ctx.client_hello_len = n; if (!ssl_early_callback_init(&early_ctx)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_CLIENTHELLO_PARSE_FAILED); goto f_err; } if (ssl->state == SSL3_ST_SR_CLNT_HELLO_B && ssl->ctx->select_certificate_cb != NULL) { ssl->state = SSL3_ST_SR_CLNT_HELLO_C; switch (ssl->ctx->select_certificate_cb(&early_ctx)) { case 0: ssl->rwstate = SSL_CERTIFICATE_SELECTION_PENDING; goto err; case -1: /* Connection rejected. */ al = SSL_AD_ACCESS_DENIED; OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); goto f_err; default: /* fallthrough */; } } ssl->state = SSL3_ST_SR_CLNT_HELLO_C; break; default: OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_STATE); return -1; } CBS_init(&client_hello, ssl->init_msg, n); if (!CBS_get_u16(&client_hello, &client_version) || !CBS_get_bytes(&client_hello, &client_random, SSL3_RANDOM_SIZE) || !CBS_get_u8_length_prefixed(&client_hello, &session_id) || CBS_len(&session_id) > SSL_MAX_SSL_SESSION_ID_LENGTH) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } /* use version from inside client hello, not from record header (may differ: * see RFC 2246, Appendix E, second paragraph) */ ssl->client_version = client_version; /* Load the client random. */ memcpy(ssl->s3->client_random, CBS_data(&client_random), SSL3_RANDOM_SIZE); if (SSL_IS_DTLS(ssl)) { CBS cookie; if (!CBS_get_u8_length_prefixed(&client_hello, &cookie) || CBS_len(&cookie) > DTLS1_COOKIE_LENGTH) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } } /* Note: This codepath may run twice if |ssl_get_prev_session| completes * asynchronously. * * TODO(davidben): Clean up the order of events around ClientHello * processing. */ if (!ssl->s3->have_version) { /* Select version to use */ uint16_t version = ssl3_get_mutual_version(ssl, client_version); if (version == 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNSUPPORTED_PROTOCOL); ssl->version = ssl->client_version; al = SSL_AD_PROTOCOL_VERSION; goto f_err; } ssl->version = version; ssl->s3->enc_method = ssl3_get_enc_method(version); assert(ssl->s3->enc_method != NULL); /* At this point, the connection's version is known and |ssl->version| is * fixed. Begin enforcing the record-layer version. */ ssl->s3->have_version = 1; } else if (SSL_IS_DTLS(ssl) ? (ssl->client_version > ssl->version) : (ssl->client_version < ssl->version)) { OPENSSL_PUT_ERROR(SSL, SSL_R_WRONG_VERSION_NUMBER); al = SSL_AD_PROTOCOL_VERSION; goto f_err; } ssl->hit = 0; int send_new_ticket = 0; switch (ssl_get_prev_session(ssl, &session, &send_new_ticket, &early_ctx)) { case ssl_session_success: break; case ssl_session_error: goto err; case ssl_session_retry: ssl->rwstate = SSL_PENDING_SESSION; goto err; } ssl->tlsext_ticket_expected = send_new_ticket; /* The EMS state is needed when making the resumption decision, but * extensions are not normally parsed until later. This detects the EMS * extension for the resumption decision and it's checked against the result * of the normal parse later in this function. */ const uint8_t *ems_data; size_t ems_len; int have_extended_master_secret = ssl->version != SSL3_VERSION && SSL_early_callback_ctx_extension_get(&early_ctx, TLSEXT_TYPE_extended_master_secret, &ems_data, &ems_len) && ems_len == 0; if (session != NULL) { if (session->extended_master_secret && !have_extended_master_secret) { /* A ClientHello without EMS that attempts to resume a session with EMS * is fatal to the connection. */ al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_RESUMED_EMS_SESSION_WITHOUT_EMS_EXTENSION); goto f_err; } ssl->hit = /* Only resume if the session's version matches the negotiated version: * most clients do not accept a mismatch. */ ssl->version == session->ssl_version && /* If the client offers the EMS extension, but the previous session * didn't use it, then negotiate a new session. */ have_extended_master_secret == session->extended_master_secret; } if (ssl->hit) { /* Use the new session. */ SSL_SESSION_free(ssl->session); ssl->session = session; session = NULL; ssl->verify_result = ssl->session->verify_result; } else { if (!ssl_get_new_session(ssl, 1 /* server */)) { goto err; } /* Clear the session ID if we want the session to be single-use. */ if (!(ssl->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER)) { ssl->session->session_id_length = 0; } } if (ssl->ctx->dos_protection_cb != NULL && ssl->ctx->dos_protection_cb(&early_ctx) == 0) { /* Connection rejected for DOS reasons. */ al = SSL_AD_ACCESS_DENIED; OPENSSL_PUT_ERROR(SSL, SSL_R_CONNECTION_REJECTED); goto f_err; } if (!CBS_get_u16_length_prefixed(&client_hello, &cipher_suites) || CBS_len(&cipher_suites) == 0 || CBS_len(&cipher_suites) % 2 != 0 || !CBS_get_u8_length_prefixed(&client_hello, &compression_methods) || CBS_len(&compression_methods) == 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } ciphers = ssl_bytes_to_cipher_list(ssl, &cipher_suites); if (ciphers == NULL) { goto err; } /* If it is a hit, check that the cipher is in the list. */ if (ssl->hit) { size_t j; int found_cipher = 0; uint32_t id = ssl->session->cipher->id; for (j = 0; j < sk_SSL_CIPHER_num(ciphers); j++) { c = sk_SSL_CIPHER_value(ciphers, j); if (c->id == id) { found_cipher = 1; break; } } if (!found_cipher) { /* we need to have the cipher in the cipher list if we are asked to reuse * it */ al = SSL_AD_ILLEGAL_PARAMETER; OPENSSL_PUT_ERROR(SSL, SSL_R_REQUIRED_CIPHER_MISSING); goto f_err; } } /* Only null compression is supported. */ if (memchr(CBS_data(&compression_methods), 0, CBS_len(&compression_methods)) == NULL) { al = SSL_AD_ILLEGAL_PARAMETER; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_COMPRESSION_SPECIFIED); goto f_err; } /* TLS extensions. */ if (ssl->version >= SSL3_VERSION && !ssl_parse_clienthello_tlsext(ssl, &client_hello)) { OPENSSL_PUT_ERROR(SSL, SSL_R_PARSE_TLSEXT); goto err; } /* There should be nothing left over in the record. */ if (CBS_len(&client_hello) != 0) { /* wrong packet length */ al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_PACKET_LENGTH); goto f_err; } if (have_extended_master_secret != ssl->s3->tmp.extended_master_secret) { al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_EMS_STATE_INCONSISTENT); goto f_err; } /* Given ciphers and SSL_get_ciphers, we must pick a cipher */ if (!ssl->hit) { if (ciphers == NULL) { al = SSL_AD_ILLEGAL_PARAMETER; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CIPHERS_PASSED); goto f_err; } /* Let cert callback update server certificates if required */ if (ssl->cert->cert_cb) { int rv = ssl->cert->cert_cb(ssl, ssl->cert->cert_cb_arg); if (rv == 0) { al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_CB_ERROR); goto f_err; } if (rv < 0) { ssl->rwstate = SSL_X509_LOOKUP; goto err; } } c = ssl3_choose_cipher(ssl, ciphers, ssl_get_cipher_preferences(ssl)); if (c == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_SHARED_CIPHER); goto f_err; } ssl->session->cipher = c; ssl->s3->tmp.new_cipher = c; /* Determine whether to request a client certificate. */ ssl->s3->tmp.cert_request = !!(ssl->verify_mode & SSL_VERIFY_PEER); /* Only request a certificate if Channel ID isn't negotiated. */ if ((ssl->verify_mode & SSL_VERIFY_PEER_IF_NO_OBC) && ssl->s3->tlsext_channel_id_valid) { ssl->s3->tmp.cert_request = 0; } /* CertificateRequest may only be sent in certificate-based ciphers. */ if (!ssl_cipher_uses_certificate_auth(ssl->s3->tmp.new_cipher)) { ssl->s3->tmp.cert_request = 0; } } else { /* Session-id reuse */ ssl->s3->tmp.new_cipher = ssl->session->cipher; ssl->s3->tmp.cert_request = 0; } /* Now that the cipher is known, initialize the handshake hash. */ if (!ssl3_init_handshake_hash(ssl)) { goto f_err; } /* In TLS 1.2, client authentication requires hashing the handshake transcript * under a different hash. Otherwise, release the handshake buffer. */ if (!ssl->s3->tmp.cert_request || ssl3_protocol_version(ssl) < TLS1_2_VERSION) { ssl3_free_handshake_buffer(ssl); } /* we now have the following setup; * client_random * cipher_list - our prefered list of ciphers * ciphers - the clients prefered list of ciphers * compression - basically ignored right now * ssl version is set - sslv3 * ssl->session - The ssl session has been setup. * ssl->hit - session reuse flag * ssl->tmp.new_cipher - the new cipher to use. */ ret = 1; if (0) { f_err: ssl3_send_alert(ssl, SSL3_AL_FATAL, al); } err: sk_SSL_CIPHER_free(ciphers); SSL_SESSION_free(session); return ret; } int ssl3_send_server_hello(SSL *ssl) { if (ssl->state == SSL3_ST_SW_SRVR_HELLO_B) { return ssl_do_write(ssl); } assert(ssl->state == SSL3_ST_SW_SRVR_HELLO_A); /* We only accept ChannelIDs on connections with ECDHE in order to avoid a * known attack while we fix ChannelID itself. */ if (ssl->s3->tlsext_channel_id_valid && (ssl->s3->tmp.new_cipher->algorithm_mkey & SSL_kECDHE) == 0) { ssl->s3->tlsext_channel_id_valid = 0; } /* If this is a resumption and the original handshake didn't support * ChannelID then we didn't record the original handshake hashes in the * session and so cannot resume with ChannelIDs. */ if (ssl->hit && ssl->session->original_handshake_hash_len == 0) { ssl->s3->tlsext_channel_id_valid = 0; } if (!ssl_fill_hello_random(ssl->s3->server_random, SSL3_RANDOM_SIZE, 1 /* server */)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); return -1; } CBB cbb, session_id; size_t length; CBB_zero(&cbb); if (!CBB_init_fixed(&cbb, ssl_handshake_start(ssl), ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl)) || !CBB_add_u16(&cbb, ssl->version) || !CBB_add_bytes(&cbb, ssl->s3->server_random, SSL3_RANDOM_SIZE) || !CBB_add_u8_length_prefixed(&cbb, &session_id) || !CBB_add_bytes(&session_id, ssl->session->session_id, ssl->session->session_id_length) || !CBB_add_u16(&cbb, ssl_cipher_get_value(ssl->s3->tmp.new_cipher)) || !CBB_add_u8(&cbb, 0 /* no compression */) || !ssl_add_serverhello_tlsext(ssl, &cbb) || !CBB_finish(&cbb, NULL, &length) || !ssl_set_handshake_header(ssl, SSL3_MT_SERVER_HELLO, length)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); CBB_cleanup(&cbb); return -1; } ssl->state = SSL3_ST_SW_SRVR_HELLO_B; return ssl_do_write(ssl); } int ssl3_send_certificate_status(SSL *ssl) { if (ssl->state == SSL3_ST_SW_CERT_STATUS_A) { CBB out, ocsp_response; size_t length; CBB_zero(&out); if (!CBB_init_fixed(&out, ssl_handshake_start(ssl), ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl)) || !CBB_add_u8(&out, TLSEXT_STATUSTYPE_ocsp) || !CBB_add_u24_length_prefixed(&out, &ocsp_response) || !CBB_add_bytes(&ocsp_response, ssl->ctx->ocsp_response, ssl->ctx->ocsp_response_length) || !CBB_finish(&out, NULL, &length) || !ssl_set_handshake_header(ssl, SSL3_MT_CERTIFICATE_STATUS, length)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); CBB_cleanup(&out); return -1; } ssl->state = SSL3_ST_SW_CERT_STATUS_B; } /* SSL3_ST_SW_CERT_STATUS_B */ return ssl_do_write(ssl); } int ssl3_send_server_done(SSL *ssl) { if (ssl->state == SSL3_ST_SW_SRVR_DONE_A) { if (!ssl_set_handshake_header(ssl, SSL3_MT_SERVER_DONE, 0)) { return -1; } ssl->state = SSL3_ST_SW_SRVR_DONE_B; } /* SSL3_ST_SW_SRVR_DONE_B */ return ssl_do_write(ssl); } int ssl3_send_server_key_exchange(SSL *ssl) { if (ssl->state == SSL3_ST_SW_KEY_EXCH_C) { return ssl_do_write(ssl); } CBB cbb, child; if (!CBB_init_fixed(&cbb, ssl_handshake_start(ssl), ssl->init_buf->max - SSL_HM_HEADER_LENGTH(ssl))) { goto err; } if (ssl->state == SSL3_ST_SW_KEY_EXCH_A) { /* This is the first iteration, so write parameters. */ uint32_t alg_k = ssl->s3->tmp.new_cipher->algorithm_mkey; uint32_t alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; /* PSK ciphers begin with an identity hint. */ if (alg_a & SSL_aPSK) { size_t len = (ssl->psk_identity_hint == NULL) ? 0 : strlen(ssl->psk_identity_hint); if (!CBB_add_u16_length_prefixed(&cbb, &child) || !CBB_add_bytes(&child, (const uint8_t *)ssl->psk_identity_hint, len)) { goto err; } } if (alg_k & SSL_kDHE) { /* Determine the group to use. */ DH *params = ssl->cert->dh_tmp; if (params == NULL && ssl->cert->dh_tmp_cb != NULL) { params = ssl->cert->dh_tmp_cb(ssl, 0, 1024); } if (params == NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_TMP_DH_KEY); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } ssl->session->key_exchange_info = DH_num_bits(params); /* Set up DH, generate a key, and emit the public half. */ DH *dh = DHparams_dup(params); if (dh == NULL) { goto err; } SSL_ECDH_CTX_init_for_dhe(&ssl->s3->tmp.ecdh_ctx, dh); if (!CBB_add_u16_length_prefixed(&cbb, &child) || !BN_bn2cbb_padded(&child, BN_num_bytes(params->p), params->p) || !CBB_add_u16_length_prefixed(&cbb, &child) || !BN_bn2cbb_padded(&child, BN_num_bytes(params->g), params->g) || !CBB_add_u16_length_prefixed(&cbb, &child) || !SSL_ECDH_CTX_offer(&ssl->s3->tmp.ecdh_ctx, &child)) { goto err; } } else if (alg_k & SSL_kECDHE) { /* Determine the group to use. */ uint16_t group_id; if (!tls1_get_shared_group(ssl, &group_id)) { OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_TMP_ECDH_KEY); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } ssl->session->key_exchange_info = group_id; /* Set up ECDH, generate a key, and emit the public half. */ if (!SSL_ECDH_CTX_init(&ssl->s3->tmp.ecdh_ctx, group_id) || !CBB_add_u8(&cbb, NAMED_CURVE_TYPE) || !CBB_add_u16(&cbb, group_id) || !CBB_add_u8_length_prefixed(&cbb, &child) || !SSL_ECDH_CTX_offer(&ssl->s3->tmp.ecdh_ctx, &child)) { goto err; } } else if (alg_k & SSL_kCECPQ1) { if (!SSL_ECDH_CTX_init(&ssl->s3->tmp.ecdh_ctx, SSL_GROUP_CECPQ1) || !CBB_add_u16_length_prefixed(&cbb, &child) || !SSL_ECDH_CTX_offer(&ssl->s3->tmp.ecdh_ctx, &child)) { goto err; } } else { assert(alg_k & SSL_kPSK); } /* Otherwise, restore |cbb| from the previous iteration. * TODO(davidben): When |ssl->init_buf| is gone, come up with a simpler * pattern. Probably keep the |CBB| around in the handshake state. */ } else if (!CBB_did_write(&cbb, ssl->init_num - SSL_HM_HEADER_LENGTH(ssl))) { goto err; } /* Add a signature. */ if (ssl_cipher_uses_certificate_auth(ssl->s3->tmp.new_cipher)) { if (!ssl_has_private_key(ssl)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } const size_t max_sig_len = ssl_private_key_max_signature_len(ssl); size_t sig_len; enum ssl_private_key_result_t sign_result; if (ssl->state == SSL3_ST_SW_KEY_EXCH_A) { /* This is the first iteration, so set up the signature. Sample the * parameter length before adding a signature algorithm. */ if (!CBB_flush(&cbb)) { goto err; } size_t params_len = CBB_len(&cbb); /* Determine signature algorithm. */ const EVP_MD *md; if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { md = tls1_choose_signing_digest(ssl); if (!tls12_add_sigandhash(ssl, &cbb, md)) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } } else if (ssl_private_key_type(ssl) == EVP_PKEY_RSA) { md = EVP_md5_sha1(); } else { md = EVP_sha1(); } /* Compute the digest and sign it. */ uint8_t digest[EVP_MAX_MD_SIZE]; unsigned digest_len = 0; EVP_MD_CTX md_ctx; EVP_MD_CTX_init(&md_ctx); int digest_ret = EVP_DigestInit_ex(&md_ctx, md, NULL) && EVP_DigestUpdate(&md_ctx, ssl->s3->client_random, SSL3_RANDOM_SIZE) && EVP_DigestUpdate(&md_ctx, ssl->s3->server_random, SSL3_RANDOM_SIZE) && EVP_DigestUpdate(&md_ctx, CBB_data(&cbb), params_len) && EVP_DigestFinal_ex(&md_ctx, digest, &digest_len); EVP_MD_CTX_cleanup(&md_ctx); uint8_t *ptr; if (!digest_ret || !CBB_add_u16_length_prefixed(&cbb, &child) || !CBB_reserve(&child, &ptr, max_sig_len)) { goto err; } sign_result = ssl_private_key_sign(ssl, ptr, &sig_len, max_sig_len, md, digest, digest_len); } else { assert(ssl->state == SSL3_ST_SW_KEY_EXCH_B); /* Retry the signature. */ uint8_t *ptr; if (!CBB_add_u16_length_prefixed(&cbb, &child) || !CBB_reserve(&child, &ptr, max_sig_len)) { goto err; } sign_result = ssl_private_key_sign_complete(ssl, ptr, &sig_len, max_sig_len); } switch (sign_result) { case ssl_private_key_success: if (!CBB_did_write(&child, sig_len)) { goto err; } break; case ssl_private_key_failure: goto err; case ssl_private_key_retry: /* Discard the unfinished signature and save the state of |cbb| for the * next iteration. */ CBB_discard_child(&cbb); ssl->init_num = SSL_HM_HEADER_LENGTH(ssl) + CBB_len(&cbb); ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; ssl->state = SSL3_ST_SW_KEY_EXCH_B; goto err; } } size_t length; if (!CBB_finish(&cbb, NULL, &length) || !ssl_set_handshake_header(ssl, SSL3_MT_SERVER_KEY_EXCHANGE, length)) { goto err; } ssl->state = SSL3_ST_SW_KEY_EXCH_C; return ssl_do_write(ssl); err: CBB_cleanup(&cbb); return -1; } int ssl3_send_certificate_request(SSL *ssl) { uint8_t *p, *d; size_t i; int j, nl, off, n; STACK_OF(X509_NAME) *sk = NULL; X509_NAME *name; BUF_MEM *buf; if (ssl->state == SSL3_ST_SW_CERT_REQ_A) { buf = ssl->init_buf; d = p = ssl_handshake_start(ssl); /* get the list of acceptable cert types */ p++; n = ssl3_get_req_cert_type(ssl, p); d[0] = n; p += n; n++; if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { const uint8_t *psigs; nl = tls12_get_psigalgs(ssl, &psigs); s2n(nl, p); memcpy(p, psigs, nl); p += nl; n += nl + 2; } off = n; p += 2; n += 2; sk = SSL_get_client_CA_list(ssl); nl = 0; if (sk != NULL) { for (i = 0; i < sk_X509_NAME_num(sk); i++) { name = sk_X509_NAME_value(sk, i); j = i2d_X509_NAME(name, NULL); if (!BUF_MEM_grow_clean(buf, SSL_HM_HEADER_LENGTH(ssl) + n + j + 2)) { OPENSSL_PUT_ERROR(SSL, ERR_R_BUF_LIB); goto err; } p = ssl_handshake_start(ssl) + n; s2n(j, p); i2d_X509_NAME(name, &p); n += 2 + j; nl += 2 + j; } } /* else no CA names */ p = ssl_handshake_start(ssl) + off; s2n(nl, p); if (!ssl_set_handshake_header(ssl, SSL3_MT_CERTIFICATE_REQUEST, n)) { goto err; } ssl->state = SSL3_ST_SW_CERT_REQ_B; } /* SSL3_ST_SW_CERT_REQ_B */ return ssl_do_write(ssl); err: return -1; } int ssl3_get_client_key_exchange(SSL *ssl) { int al; CBS client_key_exchange; uint32_t alg_k; uint32_t alg_a; uint8_t *premaster_secret = NULL; size_t premaster_secret_len = 0; uint8_t *decrypt_buf = NULL; unsigned psk_len = 0; uint8_t psk[PSK_MAX_PSK_LEN]; if (ssl->state == SSL3_ST_SR_KEY_EXCH_A) { int ok; const long n = ssl->method->ssl_get_message( ssl, SSL3_MT_CLIENT_KEY_EXCHANGE, ssl_hash_message, &ok); if (!ok) { return n; } } CBS_init(&client_key_exchange, ssl->init_msg, ssl->init_num); alg_k = ssl->s3->tmp.new_cipher->algorithm_mkey; alg_a = ssl->s3->tmp.new_cipher->algorithm_auth; /* If using a PSK key exchange, prepare the pre-shared key. */ if (alg_a & SSL_aPSK) { CBS psk_identity; /* If using PSK, the ClientKeyExchange contains a psk_identity. If PSK, * then this is the only field in the message. */ if (!CBS_get_u16_length_prefixed(&client_key_exchange, &psk_identity) || ((alg_k & SSL_kPSK) && CBS_len(&client_key_exchange) != 0)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); al = SSL_AD_DECODE_ERROR; goto f_err; } if (ssl->psk_server_callback == NULL) { OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_NO_SERVER_CB); al = SSL_AD_INTERNAL_ERROR; goto f_err; } if (CBS_len(&psk_identity) > PSK_MAX_IDENTITY_LEN || CBS_contains_zero_byte(&psk_identity)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DATA_LENGTH_TOO_LONG); al = SSL_AD_ILLEGAL_PARAMETER; goto f_err; } if (!CBS_strdup(&psk_identity, &ssl->session->psk_identity)) { al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto f_err; } /* Look up the key for the identity. */ psk_len = ssl->psk_server_callback(ssl, ssl->session->psk_identity, psk, sizeof(psk)); if (psk_len > PSK_MAX_PSK_LEN) { OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR); al = SSL_AD_INTERNAL_ERROR; goto f_err; } else if (psk_len == 0) { /* PSK related to the given identity not found */ OPENSSL_PUT_ERROR(SSL, SSL_R_PSK_IDENTITY_NOT_FOUND); al = SSL_AD_UNKNOWN_PSK_IDENTITY; goto f_err; } } /* Depending on the key exchange method, compute |premaster_secret| and * |premaster_secret_len|. */ if (alg_k & SSL_kRSA) { /* Allocate a buffer large enough for an RSA decryption. */ const size_t rsa_size = ssl_private_key_max_signature_len(ssl); decrypt_buf = OPENSSL_malloc(rsa_size); if (decrypt_buf == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } enum ssl_private_key_result_t decrypt_result; size_t decrypt_len; if (ssl->state == SSL3_ST_SR_KEY_EXCH_A) { if (!ssl_has_private_key(ssl) || ssl_private_key_type(ssl) != EVP_PKEY_RSA) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_MISSING_RSA_CERTIFICATE); goto f_err; } CBS encrypted_premaster_secret; if (ssl->version > SSL3_VERSION) { if (!CBS_get_u16_length_prefixed(&client_key_exchange, &encrypted_premaster_secret) || CBS_len(&client_key_exchange) != 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); goto f_err; } } else { encrypted_premaster_secret = client_key_exchange; } /* Decrypt with no padding. PKCS#1 padding will be removed as part of the * timing-sensitive code below. */ decrypt_result = ssl_private_key_decrypt( ssl, decrypt_buf, &decrypt_len, rsa_size, CBS_data(&encrypted_premaster_secret), CBS_len(&encrypted_premaster_secret)); } else { assert(ssl->state == SSL3_ST_SR_KEY_EXCH_B); /* Complete async decrypt. */ decrypt_result = ssl_private_key_decrypt_complete( ssl, decrypt_buf, &decrypt_len, rsa_size); } switch (decrypt_result) { case ssl_private_key_success: break; case ssl_private_key_failure: goto err; case ssl_private_key_retry: ssl->rwstate = SSL_PRIVATE_KEY_OPERATION; ssl->state = SSL3_ST_SR_KEY_EXCH_B; goto err; } if (decrypt_len != rsa_size) { al = SSL_AD_DECRYPT_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED); goto f_err; } /* Prepare a random premaster, to be used on invalid padding. See RFC 5246, * section 7.4.7.1. */ premaster_secret_len = SSL_MAX_MASTER_KEY_LENGTH; premaster_secret = OPENSSL_malloc(premaster_secret_len); if (premaster_secret == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } if (!RAND_bytes(premaster_secret, premaster_secret_len)) { goto err; } /* The smallest padded premaster is 11 bytes of overhead. Small keys are * publicly invalid. */ if (decrypt_len < 11 + premaster_secret_len) { al = SSL_AD_DECRYPT_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECRYPTION_FAILED); goto f_err; } /* Check the padding. See RFC 3447, section 7.2.2. */ size_t padding_len = decrypt_len - premaster_secret_len; uint8_t good = constant_time_eq_int_8(decrypt_buf[0], 0) & constant_time_eq_int_8(decrypt_buf[1], 2); size_t i; for (i = 2; i < padding_len - 1; i++) { good &= ~constant_time_is_zero_8(decrypt_buf[i]); } good &= constant_time_is_zero_8(decrypt_buf[padding_len - 1]); /* The premaster secret must begin with |client_version|. This too must be * checked in constant time (http://eprint.iacr.org/2003/052/). */ good &= constant_time_eq_8(decrypt_buf[padding_len], (unsigned)(ssl->client_version >> 8)); good &= constant_time_eq_8(decrypt_buf[padding_len + 1], (unsigned)(ssl->client_version & 0xff)); /* Select, in constant time, either the decrypted premaster or the random * premaster based on |good|. */ for (i = 0; i < premaster_secret_len; i++) { premaster_secret[i] = constant_time_select_8( good, decrypt_buf[padding_len + i], premaster_secret[i]); } OPENSSL_free(decrypt_buf); decrypt_buf = NULL; } else if (alg_k & (SSL_kECDHE|SSL_kDHE|SSL_kCECPQ1)) { /* Parse the ClientKeyExchange. */ CBS peer_key; if (!SSL_ECDH_CTX_get_key(&ssl->s3->tmp.ecdh_ctx, &client_key_exchange, &peer_key) || CBS_len(&client_key_exchange) != 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } /* Compute the premaster. */ uint8_t alert; if (!SSL_ECDH_CTX_finish(&ssl->s3->tmp.ecdh_ctx, &premaster_secret, &premaster_secret_len, &alert, CBS_data(&peer_key), CBS_len(&peer_key))) { al = alert; goto f_err; } /* The key exchange state may now be discarded. */ SSL_ECDH_CTX_cleanup(&ssl->s3->tmp.ecdh_ctx); } else if (alg_k & SSL_kPSK) { /* For plain PSK, other_secret is a block of 0s with the same length as the * pre-shared key. */ premaster_secret_len = psk_len; premaster_secret = OPENSSL_malloc(premaster_secret_len); if (premaster_secret == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } memset(premaster_secret, 0, premaster_secret_len); } else { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CIPHER_TYPE); goto f_err; } /* For a PSK cipher suite, the actual pre-master secret is combined with the * pre-shared key. */ if (alg_a & SSL_aPSK) { CBB new_premaster, child; uint8_t *new_data; size_t new_len; CBB_zero(&new_premaster); if (!CBB_init(&new_premaster, 2 + psk_len + 2 + premaster_secret_len) || !CBB_add_u16_length_prefixed(&new_premaster, &child) || !CBB_add_bytes(&child, premaster_secret, premaster_secret_len) || !CBB_add_u16_length_prefixed(&new_premaster, &child) || !CBB_add_bytes(&child, psk, psk_len) || !CBB_finish(&new_premaster, &new_data, &new_len)) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); CBB_cleanup(&new_premaster); goto err; } OPENSSL_cleanse(premaster_secret, premaster_secret_len); OPENSSL_free(premaster_secret); premaster_secret = new_data; premaster_secret_len = new_len; } /* Compute the master secret */ ssl->session->master_key_length = tls1_generate_master_secret( ssl, ssl->session->master_key, premaster_secret, premaster_secret_len); if (ssl->session->master_key_length == 0) { goto err; } ssl->session->extended_master_secret = ssl->s3->tmp.extended_master_secret; OPENSSL_cleanse(premaster_secret, premaster_secret_len); OPENSSL_free(premaster_secret); return 1; f_err: ssl3_send_alert(ssl, SSL3_AL_FATAL, al); err: if (premaster_secret != NULL) { OPENSSL_cleanse(premaster_secret, premaster_secret_len); OPENSSL_free(premaster_secret); } OPENSSL_free(decrypt_buf); return -1; } int ssl3_get_cert_verify(SSL *ssl) { int al, ok, ret = 0; long n; CBS certificate_verify, signature; X509 *peer = ssl->session->peer; EVP_PKEY *pkey = NULL; const EVP_MD *md = NULL; uint8_t digest[EVP_MAX_MD_SIZE]; size_t digest_length; EVP_PKEY_CTX *pctx = NULL; /* Only RSA and ECDSA client certificates are supported, so a * CertificateVerify is required if and only if there's a client certificate. * */ if (peer == NULL) { ssl3_free_handshake_buffer(ssl); return 1; } n = ssl->method->ssl_get_message(ssl, SSL3_MT_CERTIFICATE_VERIFY, ssl_dont_hash_message, &ok); if (!ok) { return n; } /* Filter out unsupported certificate types. */ pkey = X509_get_pubkey(peer); if (pkey == NULL) { goto err; } if (!(X509_certificate_type(peer, pkey) & EVP_PKT_SIGN) || (pkey->type != EVP_PKEY_RSA && pkey->type != EVP_PKEY_EC)) { al = SSL_AD_UNSUPPORTED_CERTIFICATE; OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); goto f_err; } CBS_init(&certificate_verify, ssl->init_msg, n); /* Determine the digest type if needbe. */ if (ssl3_protocol_version(ssl) >= TLS1_2_VERSION) { uint8_t hash, signature_type; if (!CBS_get_u8(&certificate_verify, &hash) || !CBS_get_u8(&certificate_verify, &signature_type)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } if (!tls12_check_peer_sigalg(ssl, &md, &al, hash, signature_type, pkey)) { goto f_err; } } /* Compute the digest. */ if (!ssl3_cert_verify_hash(ssl, digest, &digest_length, &md, pkey->type)) { goto err; } /* The handshake buffer is no longer necessary, and we may hash the current * message.*/ ssl3_free_handshake_buffer(ssl); if (!ssl3_hash_current_message(ssl)) { goto err; } /* Parse and verify the signature. */ if (!CBS_get_u16_length_prefixed(&certificate_verify, &signature) || CBS_len(&certificate_verify) != 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } pctx = EVP_PKEY_CTX_new(pkey, NULL); if (pctx == NULL) { goto err; } int sig_ok = EVP_PKEY_verify_init(pctx) && EVP_PKEY_CTX_set_signature_md(pctx, md) && EVP_PKEY_verify(pctx, CBS_data(&signature), CBS_len(&signature), digest, digest_length); #if defined(BORINGSSL_UNSAFE_FUZZER_MODE) sig_ok = 1; ERR_clear_error(); #endif if (!sig_ok) { al = SSL_AD_DECRYPT_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE); goto f_err; } ret = 1; if (0) { f_err: ssl3_send_alert(ssl, SSL3_AL_FATAL, al); } err: EVP_PKEY_CTX_free(pctx); EVP_PKEY_free(pkey); return ret; } int ssl3_get_client_certificate(SSL *ssl) { int ok, al, ret = -1; X509 *x = NULL; unsigned long n; STACK_OF(X509) *sk = NULL; SHA256_CTX sha256; CBS certificate_msg, certificate_list; int is_first_certificate = 1; assert(ssl->s3->tmp.cert_request); n = ssl->method->ssl_get_message(ssl, -1, ssl_hash_message, &ok); if (!ok) { return n; } if (ssl->s3->tmp.message_type != SSL3_MT_CERTIFICATE) { if (ssl->version == SSL3_VERSION && ssl->s3->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { /* In SSL 3.0, the Certificate message is omitted to signal no certificate. */ if ((ssl->verify_mode & SSL_VERIFY_PEER) && (ssl->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto f_err; } ssl->s3->tmp.reuse_message = 1; return 1; } al = SSL_AD_UNEXPECTED_MESSAGE; OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE); goto f_err; } CBS_init(&certificate_msg, ssl->init_msg, n); sk = sk_X509_new_null(); if (sk == NULL) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } if (!CBS_get_u24_length_prefixed(&certificate_msg, &certificate_list) || CBS_len(&certificate_msg) != 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } while (CBS_len(&certificate_list) > 0) { CBS certificate; const uint8_t *data; if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto f_err; } if (is_first_certificate && ssl->ctx->retain_only_sha256_of_client_certs) { /* If this is the first certificate, and we don't want to keep peer * certificates in memory, then we hash it right away. */ SHA256_Init(&sha256); SHA256_Update(&sha256, CBS_data(&certificate), CBS_len(&certificate)); SHA256_Final(ssl->session->peer_sha256, &sha256); ssl->session->peer_sha256_valid = 1; } is_first_certificate = 0; /* A u24 length cannot overflow a long. */ data = CBS_data(&certificate); x = d2i_X509(NULL, &data, (long)CBS_len(&certificate)); if (x == NULL) { al = SSL_AD_BAD_CERTIFICATE; OPENSSL_PUT_ERROR(SSL, ERR_R_ASN1_LIB); goto f_err; } if (data != CBS_data(&certificate) + CBS_len(&certificate)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH); goto f_err; } if (!sk_X509_push(sk, x)) { OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } x = NULL; } if (sk_X509_num(sk) <= 0) { /* No client certificate so the handshake buffer may be discarded. */ ssl3_free_handshake_buffer(ssl); /* TLS does not mind 0 certs returned */ if (ssl->version == SSL3_VERSION) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, SSL_R_NO_CERTIFICATES_RETURNED); goto f_err; } else if ((ssl->verify_mode & SSL_VERIFY_PEER) && (ssl->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { /* Fail for TLS only if we required a certificate */ OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto f_err; } } else { if (ssl_verify_cert_chain(ssl, sk) <= 0) { al = ssl_verify_alarm_type(ssl->verify_result); OPENSSL_PUT_ERROR(SSL, SSL_R_CERTIFICATE_VERIFY_FAILED); goto f_err; } } X509_free(ssl->session->peer); ssl->session->peer = sk_X509_shift(sk); ssl->session->verify_result = ssl->verify_result; sk_X509_pop_free(ssl->session->cert_chain, X509_free); ssl->session->cert_chain = sk; /* Inconsistency alert: cert_chain does *not* include the peer's own * certificate, while we do include it in s3_clnt.c */ sk = NULL; ret = 1; if (0) { f_err: ssl3_send_alert(ssl, SSL3_AL_FATAL, al); } err: X509_free(x); sk_X509_pop_free(sk, X509_free); return ret; } int ssl3_send_server_certificate(SSL *ssl) { if (ssl->state == SSL3_ST_SW_CERT_A) { if (!ssl3_output_cert_chain(ssl)) { return 0; } ssl->state = SSL3_ST_SW_CERT_B; } /* SSL3_ST_SW_CERT_B */ return ssl_do_write(ssl); } /* send a new session ticket (not necessarily for a new session) */ int ssl3_send_new_session_ticket(SSL *ssl) { int ret = -1; uint8_t *session = NULL; size_t session_len; EVP_CIPHER_CTX ctx; HMAC_CTX hctx; EVP_CIPHER_CTX_init(&ctx); HMAC_CTX_init(&hctx); if (ssl->state == SSL3_ST_SW_SESSION_TICKET_A) { uint8_t *p, *macstart; int len; unsigned int hlen; SSL_CTX *tctx = ssl->initial_ctx; uint8_t iv[EVP_MAX_IV_LENGTH]; uint8_t key_name[16]; /* The maximum overhead of encrypting the session is 16 (key name) + IV + * one block of encryption overhead + HMAC. */ const size_t max_ticket_overhead = 16 + EVP_MAX_IV_LENGTH + EVP_MAX_BLOCK_LENGTH + EVP_MAX_MD_SIZE; /* Serialize the SSL_SESSION to be encoded into the ticket. */ if (!SSL_SESSION_to_bytes_for_ticket(ssl->session, &session, &session_len)) { goto err; } /* If the session is too long, emit a dummy value rather than abort the * connection. */ if (session_len > 0xFFFF - max_ticket_overhead) { static const char kTicketPlaceholder[] = "TICKET TOO LARGE"; const size_t placeholder_len = strlen(kTicketPlaceholder); OPENSSL_free(session); session = NULL; p = ssl_handshake_start(ssl); /* Emit ticket_lifetime_hint. */ l2n(0, p); /* Emit ticket. */ s2n(placeholder_len, p); memcpy(p, kTicketPlaceholder, placeholder_len); p += placeholder_len; len = p - ssl_handshake_start(ssl); if (!ssl_set_handshake_header(ssl, SSL3_MT_NEW_SESSION_TICKET, len)) { goto err; } ssl->state = SSL3_ST_SW_SESSION_TICKET_B; return ssl_do_write(ssl); } /* Grow buffer if need be: the length calculation is as follows: * handshake_header_length + 4 (ticket lifetime hint) + 2 (ticket length) + * max_ticket_overhead + * session_length */ if (!BUF_MEM_grow(ssl->init_buf, SSL_HM_HEADER_LENGTH(ssl) + 6 + max_ticket_overhead + session_len)) { goto err; } p = ssl_handshake_start(ssl); /* Initialize HMAC and cipher contexts. If callback present it does all the * work otherwise use generated values from parent ctx. */ if (tctx->tlsext_ticket_key_cb) { if (tctx->tlsext_ticket_key_cb(ssl, key_name, iv, &ctx, &hctx, 1 /* encrypt */) < 0) { goto err; } } else { if (!RAND_bytes(iv, 16) || !EVP_EncryptInit_ex(&ctx, EVP_aes_128_cbc(), NULL, tctx->tlsext_tick_aes_key, iv) || !HMAC_Init_ex(&hctx, tctx->tlsext_tick_hmac_key, 16, tlsext_tick_md(), NULL)) { goto err; } memcpy(key_name, tctx->tlsext_tick_key_name, 16); } /* Ticket lifetime hint (advisory only): We leave this unspecified for * resumed session (for simplicity), and guess that tickets for new * sessions will live as long as their sessions. */ l2n(ssl->hit ? 0 : ssl->session->timeout, p); /* Skip ticket length for now */ p += 2; /* Output key name */ macstart = p; memcpy(p, key_name, 16); p += 16; /* output IV */ memcpy(p, iv, EVP_CIPHER_CTX_iv_length(&ctx)); p += EVP_CIPHER_CTX_iv_length(&ctx); /* Encrypt session data */ if (!EVP_EncryptUpdate(&ctx, p, &len, session, session_len)) { goto err; } p += len; if (!EVP_EncryptFinal_ex(&ctx, p, &len)) { goto err; } p += len; if (!HMAC_Update(&hctx, macstart, p - macstart) || !HMAC_Final(&hctx, p, &hlen)) { goto err; } p += hlen; /* Now write out lengths: p points to end of data written */ /* Total length */ len = p - ssl_handshake_start(ssl); /* Skip ticket lifetime hint */ p = ssl_handshake_start(ssl) + 4; s2n(len - 6, p); if (!ssl_set_handshake_header(ssl, SSL3_MT_NEW_SESSION_TICKET, len)) { goto err; } ssl->state = SSL3_ST_SW_SESSION_TICKET_B; } /* SSL3_ST_SW_SESSION_TICKET_B */ ret = ssl_do_write(ssl); err: OPENSSL_free(session); EVP_CIPHER_CTX_cleanup(&ctx); HMAC_CTX_cleanup(&hctx); return ret; } /* ssl3_get_next_proto reads a Next Protocol Negotiation handshake message. It * sets the next_proto member in s if found */ int ssl3_get_next_proto(SSL *ssl) { int ok; long n; CBS next_protocol, selected_protocol, padding; /* Clients cannot send a NextProtocol message if we didn't see the extension * in their ClientHello */ if (!ssl->s3->next_proto_neg_seen) { OPENSSL_PUT_ERROR(SSL, SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION); return -1; } n = ssl->method->ssl_get_message(ssl, SSL3_MT_NEXT_PROTO, ssl_hash_message, &ok); if (!ok) { return n; } CBS_init(&next_protocol, ssl->init_msg, n); /* The payload looks like: * uint8 proto_len; * uint8 proto[proto_len]; * uint8 padding_len; * uint8 padding[padding_len]; */ if (!CBS_get_u8_length_prefixed(&next_protocol, &selected_protocol) || !CBS_get_u8_length_prefixed(&next_protocol, &padding) || CBS_len(&next_protocol) != 0 || !CBS_stow(&selected_protocol, &ssl->s3->next_proto_negotiated, &ssl->s3->next_proto_negotiated_len)) { return 0; } return 1; } /* ssl3_get_channel_id reads and verifies a ClientID handshake message. */ int ssl3_get_channel_id(SSL *ssl) { int ret = -1, ok; long n; uint8_t channel_id_hash[EVP_MAX_MD_SIZE]; size_t channel_id_hash_len; const uint8_t *p; uint16_t extension_type; EC_GROUP *p256 = NULL; EC_KEY *key = NULL; EC_POINT *point = NULL; ECDSA_SIG sig; BIGNUM x, y; CBS encrypted_extensions, extension; n = ssl->method->ssl_get_message(ssl, SSL3_MT_CHANNEL_ID_ENCRYPTED_EXTENSIONS, ssl_dont_hash_message, &ok); if (!ok) { return n; } /* Before incorporating the EncryptedExtensions message to the handshake * hash, compute the hash that should have been signed. */ if (!tls1_channel_id_hash(ssl, channel_id_hash, &channel_id_hash_len)) { return -1; } assert(channel_id_hash_len == SHA256_DIGEST_LENGTH); if (!ssl3_hash_current_message(ssl)) { return -1; } CBS_init(&encrypted_extensions, ssl->init_msg, n); /* EncryptedExtensions could include multiple extensions, but the only * extension that could be negotiated is ChannelID, so there can only be one * entry. * * The payload looks like: * uint16 extension_type * uint16 extension_len; * uint8 x[32]; * uint8 y[32]; * uint8 r[32]; * uint8 s[32]; */ if (!CBS_get_u16(&encrypted_extensions, &extension_type) || !CBS_get_u16_length_prefixed(&encrypted_extensions, &extension) || CBS_len(&encrypted_extensions) != 0 || extension_type != TLSEXT_TYPE_channel_id || CBS_len(&extension) != TLSEXT_CHANNEL_ID_SIZE) { OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_MESSAGE); return -1; } p256 = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1); if (!p256) { OPENSSL_PUT_ERROR(SSL, SSL_R_NO_P256_SUPPORT); return -1; } BN_init(&x); BN_init(&y); sig.r = BN_new(); sig.s = BN_new(); if (sig.r == NULL || sig.s == NULL) { goto err; } p = CBS_data(&extension); if (BN_bin2bn(p + 0, 32, &x) == NULL || BN_bin2bn(p + 32, 32, &y) == NULL || BN_bin2bn(p + 64, 32, sig.r) == NULL || BN_bin2bn(p + 96, 32, sig.s) == NULL) { goto err; } point = EC_POINT_new(p256); if (!point || !EC_POINT_set_affine_coordinates_GFp(p256, point, &x, &y, NULL)) { goto err; } key = EC_KEY_new(); if (!key || !EC_KEY_set_group(key, p256) || !EC_KEY_set_public_key(key, point)) { goto err; } /* We stored the handshake hash in |tlsext_channel_id| the first time that we * were called. */ if (!ECDSA_do_verify(channel_id_hash, channel_id_hash_len, &sig, key)) { OPENSSL_PUT_ERROR(SSL, SSL_R_CHANNEL_ID_SIGNATURE_INVALID); ssl->s3->tlsext_channel_id_valid = 0; goto err; } memcpy(ssl->s3->tlsext_channel_id, p, 64); ret = 1; err: BN_free(&x); BN_free(&y); BN_free(sig.r); BN_free(sig.s); EC_KEY_free(key); EC_POINT_free(point); EC_GROUP_free(p256); return ret; }