/* $OpenBSD: ssl_srvr.c,v 1.160 2024/02/03 17:39:17 tb Exp $ */ /* 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 "bytestring.h" #include "dtls_local.h" #include "ssl_local.h" #include "ssl_sigalgs.h" #include "ssl_tlsext.h" static int ssl3_get_client_hello(SSL *s); static int ssl3_send_dtls_hello_verify_request(SSL *s); static int ssl3_send_server_hello(SSL *s); static int ssl3_send_hello_request(SSL *s); static int ssl3_send_server_certificate(SSL *s); static int ssl3_send_server_key_exchange(SSL *s); static int ssl3_send_certificate_request(SSL *s); static int ssl3_send_server_done(SSL *s); static int ssl3_get_client_certificate(SSL *s); static int ssl3_get_client_key_exchange(SSL *s); static int ssl3_get_cert_verify(SSL *s); static int ssl3_send_newsession_ticket(SSL *s); static int ssl3_send_cert_status(SSL *s); static int ssl3_send_server_change_cipher_spec(SSL *s); static int ssl3_send_server_finished(SSL *s); static int ssl3_get_client_finished(SSL *s); int ssl3_accept(SSL *s) { unsigned long alg_k; int new_state, state, skip = 0; int listen = 0; int ret = -1; ERR_clear_error(); errno = 0; if (SSL_is_dtls(s)) listen = s->d1->listen; /* init things to blank */ s->in_handshake++; if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); if (SSL_is_dtls(s)) s->d1->listen = listen; for (;;) { state = s->s3->hs.state; switch (s->s3->hs.state) { case SSL_ST_RENEGOTIATE: s->renegotiate = 1; /* s->s3->hs.state=SSL_ST_ACCEPT; */ case SSL_ST_BEFORE: case SSL_ST_ACCEPT: case SSL_ST_BEFORE|SSL_ST_ACCEPT: case SSL_ST_OK|SSL_ST_ACCEPT: s->server = 1; ssl_info_callback(s, SSL_CB_HANDSHAKE_START, 1); if (!ssl_legacy_stack_version(s, s->version)) { SSLerror(s, ERR_R_INTERNAL_ERROR); ret = -1; goto end; } if (!ssl_supported_tls_version_range(s, &s->s3->hs.our_min_tls_version, &s->s3->hs.our_max_tls_version)) { SSLerror(s, SSL_R_NO_PROTOCOLS_AVAILABLE); ret = -1; goto end; } if (!ssl_security_version(s, s->s3->hs.our_min_tls_version)) { SSLerror(s, SSL_R_VERSION_TOO_LOW); ret = -1; goto end; } if (!ssl3_setup_init_buffer(s)) { ret = -1; goto end; } if (!ssl3_setup_buffers(s)) { ret = -1; goto end; } s->init_num = 0; if (s->s3->hs.state != SSL_ST_RENEGOTIATE) { /* * Ok, we now need to push on a buffering BIO * so that the output is sent in a way that * TCP likes :-) */ if (!ssl_init_wbio_buffer(s, 1)) { ret = -1; goto end; } if (!tls1_transcript_init(s)) { ret = -1; goto end; } s->s3->hs.state = SSL3_ST_SR_CLNT_HELLO_A; s->ctx->stats.sess_accept++; } else if (!SSL_is_dtls(s) && !s->s3->send_connection_binding) { /* * Server attempting to renegotiate with * client that doesn't support secure * renegotiation. */ SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); ret = -1; goto end; } else { /* * s->s3->hs.state == SSL_ST_RENEGOTIATE, * we will just send a HelloRequest. */ s->ctx->stats.sess_accept_renegotiate++; s->s3->hs.state = SSL3_ST_SW_HELLO_REQ_A; } break; case SSL3_ST_SW_HELLO_REQ_A: case SSL3_ST_SW_HELLO_REQ_B: s->shutdown = 0; if (SSL_is_dtls(s)) { dtls1_clear_record_buffer(s); dtls1_start_timer(s); } ret = ssl3_send_hello_request(s); if (ret <= 0) goto end; if (SSL_is_dtls(s)) s->s3->hs.tls12.next_state = SSL3_ST_SR_CLNT_HELLO_A; else s->s3->hs.tls12.next_state = SSL3_ST_SW_HELLO_REQ_C; s->s3->hs.state = SSL3_ST_SW_FLUSH; s->init_num = 0; if (SSL_is_dtls(s)) { if (!tls1_transcript_init(s)) { ret = -1; goto end; } } break; case SSL3_ST_SW_HELLO_REQ_C: s->s3->hs.state = SSL_ST_OK; break; case SSL3_ST_SR_CLNT_HELLO_A: case SSL3_ST_SR_CLNT_HELLO_B: case SSL3_ST_SR_CLNT_HELLO_C: s->shutdown = 0; if (SSL_is_dtls(s)) { ret = ssl3_get_client_hello(s); if (ret <= 0) goto end; dtls1_stop_timer(s); if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) s->s3->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A; else s->s3->hs.state = SSL3_ST_SW_SRVR_HELLO_A; s->init_num = 0; /* * Reflect ClientHello sequence to remain * stateless while listening. */ if (listen) { tls12_record_layer_reflect_seq_num( s->rl); } /* If we're just listening, stop here */ if (listen && s->s3->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { ret = 2; s->d1->listen = 0; /* * Set expected sequence numbers to * continue the handshake. */ s->d1->handshake_read_seq = 2; s->d1->handshake_write_seq = 1; s->d1->next_handshake_write_seq = 1; goto end; } } else { if (s->rwstate != SSL_X509_LOOKUP) { ret = ssl3_get_client_hello(s); if (ret <= 0) goto end; } s->renegotiate = 2; s->s3->hs.state = SSL3_ST_SW_SRVR_HELLO_A; s->init_num = 0; } break; case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A: case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B: ret = ssl3_send_dtls_hello_verify_request(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_FLUSH; s->s3->hs.tls12.next_state = SSL3_ST_SR_CLNT_HELLO_A; /* HelloVerifyRequest resets Finished MAC. */ tls1_transcript_reset(s); break; case SSL3_ST_SW_SRVR_HELLO_A: case SSL3_ST_SW_SRVR_HELLO_B: if (SSL_is_dtls(s)) { s->renegotiate = 2; dtls1_start_timer(s); } ret = ssl3_send_server_hello(s); if (ret <= 0) goto end; if (s->hit) { if (s->tlsext_ticket_expected) s->s3->hs.state = SSL3_ST_SW_SESSION_TICKET_A; else s->s3->hs.state = SSL3_ST_SW_CHANGE_A; } else { s->s3->hs.state = SSL3_ST_SW_CERT_A; } s->init_num = 0; break; case SSL3_ST_SW_CERT_A: case SSL3_ST_SW_CERT_B: /* Check if it is anon DH or anon ECDH. */ if (!(s->s3->hs.cipher->algorithm_auth & SSL_aNULL)) { if (SSL_is_dtls(s)) dtls1_start_timer(s); ret = ssl3_send_server_certificate(s); if (ret <= 0) goto end; if (s->tlsext_status_expected) s->s3->hs.state = SSL3_ST_SW_CERT_STATUS_A; else s->s3->hs.state = SSL3_ST_SW_KEY_EXCH_A; } else { skip = 1; s->s3->hs.state = SSL3_ST_SW_KEY_EXCH_A; } s->init_num = 0; break; case SSL3_ST_SW_KEY_EXCH_A: case SSL3_ST_SW_KEY_EXCH_B: alg_k = s->s3->hs.cipher->algorithm_mkey; /* * Only send if using a DH key exchange. * * For ECC ciphersuites, we send a ServerKeyExchange * message only if the cipher suite is ECDHE. In other * cases, the server certificate contains the server's * public key for key exchange. */ if (alg_k & (SSL_kDHE|SSL_kECDHE)) { if (SSL_is_dtls(s)) dtls1_start_timer(s); ret = ssl3_send_server_key_exchange(s); if (ret <= 0) goto end; } else skip = 1; s->s3->hs.state = SSL3_ST_SW_CERT_REQ_A; s->init_num = 0; break; case SSL3_ST_SW_CERT_REQ_A: case SSL3_ST_SW_CERT_REQ_B: /* * Determine whether or not we need to request a * certificate. * * Do not request a certificate if: * * - We did not ask for it (SSL_VERIFY_PEER is unset). * * - SSL_VERIFY_CLIENT_ONCE is set and we are * renegotiating. * * - We are using an anonymous ciphersuites * (see section "Certificate request" in SSL 3 drafts * and in RFC 2246) ... except when the application * insists on verification (against the specs, but * s3_clnt.c accepts this for SSL 3). */ if (!(s->verify_mode & SSL_VERIFY_PEER) || ((s->session->peer_cert != NULL) && (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || ((s->s3->hs.cipher->algorithm_auth & SSL_aNULL) && !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT))) { /* No cert request. */ skip = 1; s->s3->hs.tls12.cert_request = 0; s->s3->hs.state = SSL3_ST_SW_SRVR_DONE_A; if (!SSL_is_dtls(s)) tls1_transcript_free(s); } else { s->s3->hs.tls12.cert_request = 1; if (SSL_is_dtls(s)) dtls1_start_timer(s); ret = ssl3_send_certificate_request(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_SRVR_DONE_A; s->init_num = 0; } break; case SSL3_ST_SW_SRVR_DONE_A: case SSL3_ST_SW_SRVR_DONE_B: if (SSL_is_dtls(s)) dtls1_start_timer(s); ret = ssl3_send_server_done(s); if (ret <= 0) goto end; s->s3->hs.tls12.next_state = SSL3_ST_SR_CERT_A; s->s3->hs.state = SSL3_ST_SW_FLUSH; s->init_num = 0; 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. */ s->rwstate = SSL_WRITING; if (BIO_flush(s->wbio) <= 0) { if (SSL_is_dtls(s)) { /* If the write error was fatal, stop trying. */ if (!BIO_should_retry(s->wbio)) { s->rwstate = SSL_NOTHING; s->s3->hs.state = s->s3->hs.tls12.next_state; } } ret = -1; goto end; } s->rwstate = SSL_NOTHING; s->s3->hs.state = s->s3->hs.tls12.next_state; break; case SSL3_ST_SR_CERT_A: case SSL3_ST_SR_CERT_B: if (s->s3->hs.tls12.cert_request != 0) { ret = ssl3_get_client_certificate(s); if (ret <= 0) goto end; } s->init_num = 0; s->s3->hs.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(s); if (ret <= 0) goto end; if (SSL_is_dtls(s)) { s->s3->hs.state = SSL3_ST_SR_CERT_VRFY_A; s->init_num = 0; } alg_k = s->s3->hs.cipher->algorithm_mkey; if (SSL_USE_SIGALGS(s)) { s->s3->hs.state = SSL3_ST_SR_CERT_VRFY_A; s->init_num = 0; if (!s->session->peer_cert) break; /* * Freeze the transcript for use during client * certificate verification. */ tls1_transcript_freeze(s); } else { s->s3->hs.state = SSL3_ST_SR_CERT_VRFY_A; s->init_num = 0; tls1_transcript_free(s); /* * We need to get hashes here so if there is * a client cert, it can be verified. */ if (!tls1_transcript_hash_value(s, s->s3->hs.tls12.cert_verify, sizeof(s->s3->hs.tls12.cert_verify), NULL)) { ret = -1; goto end; } } break; case SSL3_ST_SR_CERT_VRFY_A: case SSL3_ST_SR_CERT_VRFY_B: if (SSL_is_dtls(s)) s->d1->change_cipher_spec_ok = 1; else s->s3->flags |= SSL3_FLAGS_CCS_OK; /* we should decide if we expected this one */ ret = ssl3_get_cert_verify(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SR_FINISHED_A; s->init_num = 0; break; case SSL3_ST_SR_FINISHED_A: case SSL3_ST_SR_FINISHED_B: if (SSL_is_dtls(s)) s->d1->change_cipher_spec_ok = 1; else s->s3->flags |= SSL3_FLAGS_CCS_OK; ret = ssl3_get_client_finished(s); if (ret <= 0) goto end; if (SSL_is_dtls(s)) dtls1_stop_timer(s); if (s->hit) s->s3->hs.state = SSL_ST_OK; else if (s->tlsext_ticket_expected) s->s3->hs.state = SSL3_ST_SW_SESSION_TICKET_A; else s->s3->hs.state = SSL3_ST_SW_CHANGE_A; s->init_num = 0; break; case SSL3_ST_SW_SESSION_TICKET_A: case SSL3_ST_SW_SESSION_TICKET_B: ret = ssl3_send_newsession_ticket(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_CHANGE_A; s->init_num = 0; break; case SSL3_ST_SW_CERT_STATUS_A: case SSL3_ST_SW_CERT_STATUS_B: ret = ssl3_send_cert_status(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_KEY_EXCH_A; s->init_num = 0; break; case SSL3_ST_SW_CHANGE_A: case SSL3_ST_SW_CHANGE_B: ret = ssl3_send_server_change_cipher_spec(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_FINISHED_A; s->init_num = 0; s->session->cipher = s->s3->hs.cipher; if (!tls1_setup_key_block(s)) { ret = -1; goto end; } if (!tls1_change_write_cipher_state(s)) { ret = -1; goto end; } break; case SSL3_ST_SW_FINISHED_A: case SSL3_ST_SW_FINISHED_B: ret = ssl3_send_server_finished(s); if (ret <= 0) goto end; s->s3->hs.state = SSL3_ST_SW_FLUSH; if (s->hit) { s->s3->hs.tls12.next_state = SSL3_ST_SR_FINISHED_A; tls1_transcript_free(s); } else s->s3->hs.tls12.next_state = SSL_ST_OK; s->init_num = 0; break; case SSL_ST_OK: /* clean a few things up */ tls1_cleanup_key_block(s); if (s->s3->handshake_transcript != NULL) { SSLerror(s, ERR_R_INTERNAL_ERROR); ret = -1; goto end; } if (!SSL_is_dtls(s)) ssl3_release_init_buffer(s); /* remove buffering on output */ ssl_free_wbio_buffer(s); s->init_num = 0; /* Skipped if we just sent a HelloRequest. */ if (s->renegotiate == 2) { s->renegotiate = 0; s->new_session = 0; ssl_update_cache(s, SSL_SESS_CACHE_SERVER); s->ctx->stats.sess_accept_good++; /* s->server=1; */ s->handshake_func = ssl3_accept; ssl_info_callback(s, SSL_CB_HANDSHAKE_DONE, 1); } ret = 1; if (SSL_is_dtls(s)) { /* Done handshaking, next message is client hello. */ s->d1->handshake_read_seq = 0; /* Next message is server hello. */ s->d1->handshake_write_seq = 0; s->d1->next_handshake_write_seq = 0; } goto end; /* break; */ default: SSLerror(s, SSL_R_UNKNOWN_STATE); ret = -1; goto end; /* break; */ } if (!s->s3->hs.tls12.reuse_message && !skip) { if (s->s3->hs.state != state) { new_state = s->s3->hs.state; s->s3->hs.state = state; ssl_info_callback(s, SSL_CB_ACCEPT_LOOP, 1); s->s3->hs.state = new_state; } } skip = 0; } end: /* BIO_flush(s->wbio); */ s->in_handshake--; ssl_info_callback(s, SSL_CB_ACCEPT_EXIT, ret); return (ret); } static int ssl3_send_hello_request(SSL *s) { CBB cbb, hello; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_HELLO_REQ_A) { if (!ssl3_handshake_msg_start(s, &cbb, &hello, SSL3_MT_HELLO_REQUEST)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_HELLO_REQ_B; } /* SSL3_ST_SW_HELLO_REQ_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_get_client_hello(SSL *s) { CBS cbs, client_random, session_id, cookie, cipher_suites; CBS compression_methods; uint16_t client_version; uint8_t comp_method; int comp_null; int i, j, al, ret, cookie_valid = 0; unsigned long id; SSL_CIPHER *c; STACK_OF(SSL_CIPHER) *ciphers = NULL; const SSL_METHOD *method; uint16_t shared_version; /* * 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. */ if (s->s3->hs.state == SSL3_ST_SR_CLNT_HELLO_A) s->s3->hs.state = SSL3_ST_SR_CLNT_HELLO_B; s->first_packet = 1; if ((ret = ssl3_get_message(s, SSL3_ST_SR_CLNT_HELLO_B, SSL3_ST_SR_CLNT_HELLO_C, SSL3_MT_CLIENT_HELLO, SSL3_RT_MAX_PLAIN_LENGTH)) <= 0) return ret; s->first_packet = 0; ret = -1; if (s->init_num < 0) goto err; CBS_init(&cbs, s->init_msg, s->init_num); /* Parse client hello up until the extensions (if any). */ if (!CBS_get_u16(&cbs, &client_version)) goto decode_err; if (!CBS_get_bytes(&cbs, &client_random, SSL3_RANDOM_SIZE)) goto decode_err; if (!CBS_get_u8_length_prefixed(&cbs, &session_id)) goto decode_err; if (CBS_len(&session_id) > SSL3_SESSION_ID_SIZE) { al = SSL_AD_ILLEGAL_PARAMETER; SSLerror(s, SSL_R_SSL3_SESSION_ID_TOO_LONG); goto fatal_err; } if (SSL_is_dtls(s)) { if (!CBS_get_u8_length_prefixed(&cbs, &cookie)) goto decode_err; } if (!CBS_get_u16_length_prefixed(&cbs, &cipher_suites)) goto decode_err; if (!CBS_get_u8_length_prefixed(&cbs, &compression_methods)) goto decode_err; /* * Use version from inside client hello, not from record header. * (may differ: see RFC 2246, Appendix E, second paragraph) */ if (!ssl_max_shared_version(s, client_version, &shared_version)) { if ((client_version >> 8) == SSL3_VERSION_MAJOR && !tls12_record_layer_write_protected(s->rl)) { /* * Similar to ssl3_get_record, send alert using remote * version number. */ s->version = client_version; } SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); al = SSL_AD_PROTOCOL_VERSION; goto fatal_err; } s->s3->hs.peer_legacy_version = client_version; s->version = shared_version; s->s3->hs.negotiated_tls_version = ssl_tls_version(shared_version); if (s->s3->hs.negotiated_tls_version == 0) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } if ((method = ssl_get_method(shared_version)) == NULL) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } s->method = method; /* * If we require cookies (DTLS) and this ClientHello does not contain * one, just return since we do not want to allocate any memory yet. * So check cookie length... */ if (SSL_is_dtls(s)) { if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) { if (CBS_len(&cookie) == 0) return (1); } } if (!CBS_write_bytes(&client_random, s->s3->client_random, sizeof(s->s3->client_random), NULL)) goto err; s->hit = 0; /* * Versions before 0.9.7 always allow clients to resume sessions in * renegotiation. 0.9.7 and later allow this by default, but optionally * ignore resumption requests with flag * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION (it's a new flag * rather than a change to default behavior so that applications * relying on this for security won't even compile against older * library versions). * * 1.0.1 and later also have a function SSL_renegotiate_abbreviated() * to request renegotiation but not a new session (s->new_session * remains unset): for servers, this essentially just means that the * SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be * ignored. */ if ((s->new_session && (s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) { if (!ssl_get_new_session(s, 1)) goto err; } else { CBS ext_block; CBS_dup(&cbs, &ext_block); i = ssl_get_prev_session(s, &session_id, &ext_block, &al); if (i == 1) { /* previous session */ s->hit = 1; } else if (i == -1) goto fatal_err; else { /* i == 0 */ if (!ssl_get_new_session(s, 1)) goto err; } } if (SSL_is_dtls(s)) { /* * The ClientHello may contain a cookie even if the HelloVerify * message has not been sent - make sure that it does not cause * an overflow. */ if (CBS_len(&cookie) > sizeof(s->d1->rcvd_cookie)) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_COOKIE_MISMATCH); goto fatal_err; } /* Verify the cookie if appropriate option is set. */ if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && CBS_len(&cookie) > 0) { size_t cookie_len; /* XXX - rcvd_cookie seems to only be used here... */ if (!CBS_write_bytes(&cookie, s->d1->rcvd_cookie, sizeof(s->d1->rcvd_cookie), &cookie_len)) goto err; if (s->ctx->app_verify_cookie_cb != NULL) { if (s->ctx->app_verify_cookie_cb(s, s->d1->rcvd_cookie, cookie_len) == 0) { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_COOKIE_MISMATCH); goto fatal_err; } /* else cookie verification succeeded */ /* XXX - can d1->cookie_len > sizeof(rcvd_cookie) ? */ } else if (timingsafe_memcmp(s->d1->rcvd_cookie, s->d1->cookie, s->d1->cookie_len) != 0) { /* default verification */ al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_COOKIE_MISMATCH); goto fatal_err; } cookie_valid = 1; } } /* XXX - This logic seems wrong... */ if (CBS_len(&cipher_suites) == 0 && CBS_len(&session_id) != 0) { /* we need a cipher if we are not resuming a session */ al = SSL_AD_ILLEGAL_PARAMETER; SSLerror(s, SSL_R_NO_CIPHERS_SPECIFIED); goto fatal_err; } if (CBS_len(&cipher_suites) > 0) { if ((ciphers = ssl_bytes_to_cipher_list(s, &cipher_suites)) == NULL) goto err; } /* If it is a hit, check that the cipher is in the list */ /* XXX - CBS_len(&cipher_suites) will always be zero here... */ if (s->hit && CBS_len(&cipher_suites) > 0) { j = 0; id = s->session->cipher->id; for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) { c = sk_SSL_CIPHER_value(ciphers, i); if (c->id == id) { j = 1; break; } } if (j == 0) { /* * We need to have the cipher in the cipher * list if we are asked to reuse it */ al = SSL_AD_ILLEGAL_PARAMETER; SSLerror(s, SSL_R_REQUIRED_CIPHER_MISSING); goto fatal_err; } } comp_null = 0; while (CBS_len(&compression_methods) > 0) { if (!CBS_get_u8(&compression_methods, &comp_method)) goto decode_err; if (comp_method == 0) comp_null = 1; } if (comp_null == 0) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_NO_COMPRESSION_SPECIFIED); goto fatal_err; } if (!tlsext_server_parse(s, SSL_TLSEXT_MSG_CH, &cbs, &al)) { SSLerror(s, SSL_R_PARSE_TLSEXT); goto fatal_err; } if (CBS_len(&cbs) != 0) goto decode_err; if (!s->s3->renegotiate_seen && s->renegotiate) { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); goto fatal_err; } if (ssl_check_clienthello_tlsext_early(s) <= 0) { SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); goto err; } /* * Check if we want to use external pre-shared secret for this * handshake for not reused session only. We need to generate * server_random before calling tls_session_secret_cb in order to allow * SessionTicket processing to use it in key derivation. */ arc4random_buf(s->s3->server_random, SSL3_RANDOM_SIZE); if (s->s3->hs.our_max_tls_version >= TLS1_2_VERSION && s->s3->hs.negotiated_tls_version < s->s3->hs.our_max_tls_version) { /* * RFC 8446 section 4.1.3. If we are downgrading from TLS 1.3 * we must set the last 8 bytes of the server random to magical * values to indicate we meant to downgrade. For TLS 1.2 it is * recommended that we do the same. */ size_t index = SSL3_RANDOM_SIZE - sizeof(tls13_downgrade_12); uint8_t *magic = &s->s3->server_random[index]; if (s->s3->hs.negotiated_tls_version == TLS1_2_VERSION) { /* Indicate we chose to downgrade to 1.2. */ memcpy(magic, tls13_downgrade_12, sizeof(tls13_downgrade_12)); } else { /* Indicate we chose to downgrade to 1.1 or lower */ memcpy(magic, tls13_downgrade_11, sizeof(tls13_downgrade_11)); } } if (!s->hit && s->tls_session_secret_cb != NULL) { SSL_CIPHER *pref_cipher = NULL; int master_key_length = sizeof(s->session->master_key); if (!s->tls_session_secret_cb(s, s->session->master_key, &master_key_length, ciphers, &pref_cipher, s->tls_session_secret_cb_arg)) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } if (master_key_length <= 0) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } s->session->master_key_length = master_key_length; s->hit = 1; s->session->verify_result = X509_V_OK; sk_SSL_CIPHER_free(s->session->ciphers); s->session->ciphers = ciphers; ciphers = NULL; /* Check if some cipher was preferred by the callback. */ if (pref_cipher == NULL) pref_cipher = ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s)); if (pref_cipher == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_NO_SHARED_CIPHER); goto fatal_err; } s->session->cipher = pref_cipher; sk_SSL_CIPHER_free(s->cipher_list); s->cipher_list = sk_SSL_CIPHER_dup(s->session->ciphers); } /* * Given s->session->ciphers and SSL_get_ciphers, we must * pick a cipher */ if (!s->hit) { if (ciphers == NULL) { al = SSL_AD_ILLEGAL_PARAMETER; SSLerror(s, SSL_R_NO_CIPHERS_PASSED); goto fatal_err; } sk_SSL_CIPHER_free(s->session->ciphers); s->session->ciphers = ciphers; ciphers = NULL; if ((c = ssl3_choose_cipher(s, s->session->ciphers, SSL_get_ciphers(s))) == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_NO_SHARED_CIPHER); goto fatal_err; } s->s3->hs.cipher = c; } else { s->s3->hs.cipher = s->session->cipher; } if (!tls1_transcript_hash_init(s)) goto err; if (!SSL_USE_SIGALGS(s) || !(s->verify_mode & SSL_VERIFY_PEER)) tls1_transcript_free(s); /* * We now have the following setup. * client_random * cipher_list - our preferred list of ciphers * ciphers - the clients preferred list of ciphers * compression - basically ignored right now * ssl version is set - sslv3 * s->session - The ssl session has been setup. * s->hit - session reuse flag * s->hs.cipher - the new cipher to use. */ /* Handles TLS extensions that we couldn't check earlier */ if (ssl_check_clienthello_tlsext_late(s) <= 0) { SSLerror(s, SSL_R_CLIENTHELLO_TLSEXT); goto err; } ret = cookie_valid ? 2 : 1; if (0) { decode_err: al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_PACKET_LENGTH); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); } err: sk_SSL_CIPHER_free(ciphers); return (ret); } static int ssl3_send_dtls_hello_verify_request(SSL *s) { CBB cbb, verify, cookie; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) { if (s->ctx->app_gen_cookie_cb == NULL || s->ctx->app_gen_cookie_cb(s, s->d1->cookie, &(s->d1->cookie_len)) == 0) { SSLerror(s, ERR_R_INTERNAL_ERROR); return 0; } /* * Per RFC 6347 section 4.2.1, the HelloVerifyRequest should * always contain DTLSv1.0 regardless of the version that is * going to be negotiated. */ if (!ssl3_handshake_msg_start(s, &cbb, &verify, DTLS1_MT_HELLO_VERIFY_REQUEST)) goto err; if (!CBB_add_u16(&verify, DTLS1_VERSION)) goto err; if (!CBB_add_u8_length_prefixed(&verify, &cookie)) goto err; if (!CBB_add_bytes(&cookie, s->d1->cookie, s->d1->cookie_len)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B; } /* s->s3->hs.state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_send_server_hello(SSL *s) { CBB cbb, server_hello, session_id; size_t sl; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_SRVR_HELLO_A) { if (!ssl3_handshake_msg_start(s, &cbb, &server_hello, SSL3_MT_SERVER_HELLO)) goto err; if (!CBB_add_u16(&server_hello, s->version)) goto err; if (!CBB_add_bytes(&server_hello, s->s3->server_random, sizeof(s->s3->server_random))) goto err; /* * There are several cases for the session ID to send * back in the server hello: * * - For session reuse from the session cache, * we send back the old session ID. * - If stateless session reuse (using a session ticket) * is successful, we send back the client's "session ID" * (which doesn't actually identify the session). * - If it is a new session, we send back the new * session ID. * - However, if we want the new session to be single-use, * we send back a 0-length session ID. * * s->hit is non-zero in either case of session reuse, * so the following won't overwrite an ID that we're supposed * to send back. */ if (!(s->ctx->session_cache_mode & SSL_SESS_CACHE_SERVER) && !s->hit) s->session->session_id_length = 0; sl = s->session->session_id_length; if (sl > sizeof(s->session->session_id)) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } if (!CBB_add_u8_length_prefixed(&server_hello, &session_id)) goto err; if (!CBB_add_bytes(&session_id, s->session->session_id, sl)) goto err; /* Cipher suite. */ if (!CBB_add_u16(&server_hello, ssl3_cipher_get_value(s->s3->hs.cipher))) goto err; /* Compression method (null). */ if (!CBB_add_u8(&server_hello, 0)) goto err; /* TLS extensions */ if (!tlsext_server_build(s, SSL_TLSEXT_MSG_SH, &server_hello)) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; } /* SSL3_ST_SW_SRVR_HELLO_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_send_server_done(SSL *s) { CBB cbb, done; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_SRVR_DONE_A) { if (!ssl3_handshake_msg_start(s, &cbb, &done, SSL3_MT_SERVER_DONE)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_SRVR_DONE_B; } /* SSL3_ST_SW_SRVR_DONE_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_send_server_kex_dhe(SSL *s, CBB *cbb) { int nid = NID_dhKeyAgreement; tls_key_share_free(s->s3->hs.key_share); if ((s->s3->hs.key_share = tls_key_share_new_nid(nid)) == NULL) goto err; if (s->cert->dhe_params_auto != 0) { size_t key_bits; if ((key_bits = ssl_dhe_params_auto_key_bits(s)) == 0) { SSLerror(s, ERR_R_INTERNAL_ERROR); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } tls_key_share_set_key_bits(s->s3->hs.key_share, key_bits); } else { DH *dh_params = s->cert->dhe_params; if (dh_params == NULL && s->cert->dhe_params_cb != NULL) dh_params = s->cert->dhe_params_cb(s, 0, SSL_C_PKEYLENGTH(s->s3->hs.cipher)); if (dh_params == NULL) { SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } if (!tls_key_share_set_dh_params(s->s3->hs.key_share, dh_params)) goto err; } if (!tls_key_share_generate(s->s3->hs.key_share)) goto err; if (!tls_key_share_params(s->s3->hs.key_share, cbb)) goto err; if (!tls_key_share_public(s->s3->hs.key_share, cbb)) goto err; if (!tls_key_share_peer_security(s, s->s3->hs.key_share)) { SSLerror(s, SSL_R_DH_KEY_TOO_SMALL); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); return 0; } return 1; err: return 0; } static int ssl3_send_server_kex_ecdhe(SSL *s, CBB *cbb) { CBB public; int nid; if (!tls1_get_supported_group(s, &nid)) { SSLerror(s, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } tls_key_share_free(s->s3->hs.key_share); if ((s->s3->hs.key_share = tls_key_share_new_nid(nid)) == NULL) goto err; if (!tls_key_share_generate(s->s3->hs.key_share)) goto err; /* * ECC key exchange - see RFC 8422, section 5.4. */ if (!CBB_add_u8(cbb, NAMED_CURVE_TYPE)) goto err; if (!CBB_add_u16(cbb, tls_key_share_group(s->s3->hs.key_share))) goto err; if (!CBB_add_u8_length_prefixed(cbb, &public)) goto err; if (!tls_key_share_public(s->s3->hs.key_share, &public)) goto err; if (!CBB_flush(cbb)) goto err; return 1; err: return 0; } static int ssl3_send_server_key_exchange(SSL *s) { CBB cbb, cbb_signature, cbb_signed_params, server_kex; CBS params; const struct ssl_sigalg *sigalg = NULL; unsigned char *signed_params = NULL; size_t signed_params_len; unsigned char *signature = NULL; size_t signature_len = 0; const EVP_MD *md = NULL; unsigned long type; EVP_MD_CTX *md_ctx = NULL; EVP_PKEY_CTX *pctx; EVP_PKEY *pkey; int al; memset(&cbb, 0, sizeof(cbb)); memset(&cbb_signed_params, 0, sizeof(cbb_signed_params)); if ((md_ctx = EVP_MD_CTX_new()) == NULL) goto err; if (s->s3->hs.state == SSL3_ST_SW_KEY_EXCH_A) { if (!ssl3_handshake_msg_start(s, &cbb, &server_kex, SSL3_MT_SERVER_KEY_EXCHANGE)) goto err; if (!CBB_init(&cbb_signed_params, 0)) goto err; if (!CBB_add_bytes(&cbb_signed_params, s->s3->client_random, SSL3_RANDOM_SIZE)) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } if (!CBB_add_bytes(&cbb_signed_params, s->s3->server_random, SSL3_RANDOM_SIZE)) { SSLerror(s, ERR_R_INTERNAL_ERROR); goto err; } type = s->s3->hs.cipher->algorithm_mkey; if (type & SSL_kDHE) { if (!ssl3_send_server_kex_dhe(s, &cbb_signed_params)) goto err; } else if (type & SSL_kECDHE) { if (!ssl3_send_server_kex_ecdhe(s, &cbb_signed_params)) goto err; } else { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); goto fatal_err; } if (!CBB_finish(&cbb_signed_params, &signed_params, &signed_params_len)) goto err; CBS_init(¶ms, signed_params, signed_params_len); if (!CBS_skip(¶ms, 2 * SSL3_RANDOM_SIZE)) goto err; if (!CBB_add_bytes(&server_kex, CBS_data(¶ms), CBS_len(¶ms))) goto err; /* Add signature unless anonymous. */ if (!(s->s3->hs.cipher->algorithm_auth & SSL_aNULL)) { if ((pkey = ssl_get_sign_pkey(s, s->s3->hs.cipher, &md, &sigalg)) == NULL) { al = SSL_AD_DECODE_ERROR; goto fatal_err; } s->s3->hs.our_sigalg = sigalg; /* Send signature algorithm. */ if (SSL_USE_SIGALGS(s)) { if (!CBB_add_u16(&server_kex, sigalg->value)) { al = SSL_AD_INTERNAL_ERROR; SSLerror(s, ERR_R_INTERNAL_ERROR); goto fatal_err; } } if (!EVP_DigestSignInit(md_ctx, &pctx, md, NULL, pkey)) { SSLerror(s, ERR_R_EVP_LIB); goto err; } if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && (!EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) || !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { SSLerror(s, ERR_R_EVP_LIB); goto err; } if (!EVP_DigestSign(md_ctx, NULL, &signature_len, signed_params, signed_params_len)) { SSLerror(s, ERR_R_EVP_LIB); goto err; } if ((signature = calloc(1, signature_len)) == NULL) { SSLerror(s, ERR_R_MALLOC_FAILURE); goto err; } if (!EVP_DigestSign(md_ctx, signature, &signature_len, signed_params, signed_params_len)) { SSLerror(s, ERR_R_EVP_LIB); goto err; } if (!CBB_add_u16_length_prefixed(&server_kex, &cbb_signature)) goto err; if (!CBB_add_bytes(&cbb_signature, signature, signature_len)) goto err; } if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_KEY_EXCH_B; } EVP_MD_CTX_free(md_ctx); free(signature); free(signed_params); return (ssl3_handshake_write(s)); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); err: CBB_cleanup(&cbb_signed_params); CBB_cleanup(&cbb); EVP_MD_CTX_free(md_ctx); free(signature); free(signed_params); return (-1); } static int ssl3_send_certificate_request(SSL *s) { CBB cbb, cert_request, cert_types, sigalgs, cert_auth, dn; STACK_OF(X509_NAME) *sk = NULL; X509_NAME *name; int i; /* * Certificate Request - RFC 5246 section 7.4.4. */ memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_CERT_REQ_A) { if (!ssl3_handshake_msg_start(s, &cbb, &cert_request, SSL3_MT_CERTIFICATE_REQUEST)) goto err; if (!CBB_add_u8_length_prefixed(&cert_request, &cert_types)) goto err; if (!ssl3_get_req_cert_types(s, &cert_types)) goto err; if (SSL_USE_SIGALGS(s)) { if (!CBB_add_u16_length_prefixed(&cert_request, &sigalgs)) goto err; if (!ssl_sigalgs_build(s->s3->hs.negotiated_tls_version, &sigalgs, SSL_get_security_level(s))) goto err; } if (!CBB_add_u16_length_prefixed(&cert_request, &cert_auth)) goto err; sk = SSL_get_client_CA_list(s); for (i = 0; i < sk_X509_NAME_num(sk); i++) { unsigned char *name_data; size_t name_len; name = sk_X509_NAME_value(sk, i); name_len = i2d_X509_NAME(name, NULL); if (!CBB_add_u16_length_prefixed(&cert_auth, &dn)) goto err; if (!CBB_add_space(&dn, &name_data, name_len)) goto err; if (i2d_X509_NAME(name, &name_data) != name_len) goto err; } if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_CERT_REQ_B; } /* SSL3_ST_SW_CERT_REQ_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_get_client_kex_rsa(SSL *s, CBS *cbs) { unsigned char fakekey[SSL_MAX_MASTER_KEY_LENGTH]; unsigned char *pms = NULL; unsigned char *p; size_t pms_len = 0; EVP_PKEY *pkey = NULL; RSA *rsa = NULL; CBS enc_pms; int decrypt_len; int al = -1; arc4random_buf(fakekey, sizeof(fakekey)); fakekey[0] = s->s3->hs.peer_legacy_version >> 8; fakekey[1] = s->s3->hs.peer_legacy_version & 0xff; pkey = s->cert->pkeys[SSL_PKEY_RSA].privatekey; if (pkey == NULL || (rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_MISSING_RSA_CERTIFICATE); goto fatal_err; } pms_len = RSA_size(rsa); if (pms_len < SSL_MAX_MASTER_KEY_LENGTH) goto err; if ((pms = malloc(pms_len)) == NULL) goto err; p = pms; if (!CBS_get_u16_length_prefixed(cbs, &enc_pms)) goto decode_err; if (CBS_len(cbs) != 0 || CBS_len(&enc_pms) != RSA_size(rsa)) { SSLerror(s, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); goto err; } decrypt_len = RSA_private_decrypt(CBS_len(&enc_pms), CBS_data(&enc_pms), pms, rsa, RSA_PKCS1_PADDING); ERR_clear_error(); if (decrypt_len != SSL_MAX_MASTER_KEY_LENGTH) { al = SSL_AD_DECODE_ERROR; /* SSLerror(s, SSL_R_BAD_RSA_DECRYPT); */ } if ((al == -1) && !((pms[0] == (s->s3->hs.peer_legacy_version >> 8)) && (pms[1] == (s->s3->hs.peer_legacy_version & 0xff)))) { /* * The premaster secret must contain the same version number * as the ClientHello to detect version rollback attacks * (strangely, the protocol does not offer such protection for * DH ciphersuites). * * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack * (http://eprint.iacr.org/2003/052/) exploits the version * number check as a "bad version oracle" -- an alert would * reveal that the plaintext corresponding to some ciphertext * made up by the adversary is properly formatted except that * the version number is wrong. To avoid such attacks, we should * treat this just like any other decryption error. */ al = SSL_AD_DECODE_ERROR; /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */ } if (al != -1) { /* * Some decryption failure -- use random value instead * as countermeasure against Bleichenbacher's attack * on PKCS #1 v1.5 RSA padding (see RFC 2246, * section 7.4.7.1). */ p = fakekey; } if (!tls12_derive_master_secret(s, p, SSL_MAX_MASTER_KEY_LENGTH)) goto err; freezero(pms, pms_len); return 1; decode_err: al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_PACKET_LENGTH); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); err: freezero(pms, pms_len); return 0; } static int ssl3_get_client_kex_dhe(SSL *s, CBS *cbs) { uint8_t *key = NULL; size_t key_len = 0; int decode_error, invalid_key; int ret = 0; if (s->s3->hs.key_share == NULL) { SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); goto err; } if (!tls_key_share_peer_public(s->s3->hs.key_share, cbs, &decode_error, &invalid_key)) { if (decode_error) { SSLerror(s, SSL_R_BAD_PACKET_LENGTH); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); } goto err; } if (invalid_key) { SSLerror(s, SSL_R_BAD_DH_PUB_KEY_LENGTH); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); goto err; } if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len)) goto err; if (!tls12_derive_master_secret(s, key, key_len)) goto err; ret = 1; err: freezero(key, key_len); return ret; } static int ssl3_get_client_kex_ecdhe(SSL *s, CBS *cbs) { uint8_t *key = NULL; size_t key_len = 0; int decode_error; CBS public; int ret = 0; if (s->s3->hs.key_share == NULL) { ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); SSLerror(s, SSL_R_MISSING_TMP_DH_KEY); goto err; } if (!CBS_get_u8_length_prefixed(cbs, &public)) { SSLerror(s, SSL_R_BAD_PACKET_LENGTH); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } if (!tls_key_share_peer_public(s->s3->hs.key_share, &public, &decode_error, NULL)) { if (decode_error) { SSLerror(s, SSL_R_BAD_PACKET_LENGTH); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); } goto err; } if (!tls_key_share_derive(s->s3->hs.key_share, &key, &key_len)) goto err; if (!tls12_derive_master_secret(s, key, key_len)) goto err; ret = 1; err: freezero(key, key_len); return ret; } static int ssl3_get_client_key_exchange(SSL *s) { unsigned long alg_k; int al, ret; CBS cbs; /* 2048 maxlen is a guess. How long a key does that permit? */ if ((ret = ssl3_get_message(s, SSL3_ST_SR_KEY_EXCH_A, SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048)) <= 0) return ret; if (s->init_num < 0) goto err; CBS_init(&cbs, s->init_msg, s->init_num); alg_k = s->s3->hs.cipher->algorithm_mkey; if (alg_k & SSL_kRSA) { if (!ssl3_get_client_kex_rsa(s, &cbs)) goto err; } else if (alg_k & SSL_kDHE) { if (!ssl3_get_client_kex_dhe(s, &cbs)) goto err; } else if (alg_k & SSL_kECDHE) { if (!ssl3_get_client_kex_ecdhe(s, &cbs)) goto err; } else { al = SSL_AD_HANDSHAKE_FAILURE; SSLerror(s, SSL_R_UNKNOWN_CIPHER_TYPE); goto fatal_err; } if (CBS_len(&cbs) != 0) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_PACKET_LENGTH); goto fatal_err; } return (1); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); err: return (-1); } static int ssl3_get_cert_verify(SSL *s) { CBS cbs, signature; const struct ssl_sigalg *sigalg = NULL; uint16_t sigalg_value = SIGALG_NONE; EVP_PKEY *pkey; X509 *peer_cert = NULL; EVP_MD_CTX *mctx = NULL; int al, verify; const unsigned char *hdata; size_t hdatalen; int type = 0; int ret; if ((ret = ssl3_get_message(s, SSL3_ST_SR_CERT_VRFY_A, SSL3_ST_SR_CERT_VRFY_B, -1, SSL3_RT_MAX_PLAIN_LENGTH)) <= 0) return ret; ret = 0; if (s->init_num < 0) goto err; if ((mctx = EVP_MD_CTX_new()) == NULL) goto err; CBS_init(&cbs, s->init_msg, s->init_num); peer_cert = s->session->peer_cert; pkey = X509_get0_pubkey(peer_cert); type = X509_certificate_type(peer_cert, pkey); if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE_VERIFY) { s->s3->hs.tls12.reuse_message = 1; if (peer_cert != NULL) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerror(s, SSL_R_MISSING_VERIFY_MESSAGE); goto fatal_err; } ret = 1; goto end; } if (peer_cert == NULL) { SSLerror(s, SSL_R_NO_CLIENT_CERT_RECEIVED); al = SSL_AD_UNEXPECTED_MESSAGE; goto fatal_err; } if (!(type & EVP_PKT_SIGN)) { SSLerror(s, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); al = SSL_AD_ILLEGAL_PARAMETER; goto fatal_err; } if (s->s3->change_cipher_spec) { SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); al = SSL_AD_UNEXPECTED_MESSAGE; goto fatal_err; } if (SSL_USE_SIGALGS(s)) { if (!CBS_get_u16(&cbs, &sigalg_value)) goto decode_err; } if (!CBS_get_u16_length_prefixed(&cbs, &signature)) goto err; if (CBS_len(&cbs) != 0) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_EXTRA_DATA_IN_MESSAGE); goto fatal_err; } if (CBS_len(&signature) > EVP_PKEY_size(pkey)) { SSLerror(s, SSL_R_WRONG_SIGNATURE_SIZE); al = SSL_AD_DECODE_ERROR; goto fatal_err; } if ((sigalg = ssl_sigalg_for_peer(s, pkey, sigalg_value)) == NULL) { al = SSL_AD_DECODE_ERROR; goto fatal_err; } s->s3->hs.peer_sigalg = sigalg; if (SSL_USE_SIGALGS(s)) { EVP_PKEY_CTX *pctx; if (!tls1_transcript_data(s, &hdata, &hdatalen)) { SSLerror(s, ERR_R_INTERNAL_ERROR); al = SSL_AD_INTERNAL_ERROR; goto fatal_err; } if (!EVP_DigestVerifyInit(mctx, &pctx, sigalg->md(), NULL, pkey)) { SSLerror(s, ERR_R_EVP_LIB); al = SSL_AD_INTERNAL_ERROR; goto fatal_err; } if ((sigalg->flags & SIGALG_FLAG_RSA_PSS) && (!EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) || !EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1))) { al = SSL_AD_INTERNAL_ERROR; goto fatal_err; } if (EVP_DigestVerify(mctx, CBS_data(&signature), CBS_len(&signature), hdata, hdatalen) <= 0) { SSLerror(s, ERR_R_EVP_LIB); al = SSL_AD_INTERNAL_ERROR; goto fatal_err; } } else if (EVP_PKEY_id(pkey) == EVP_PKEY_RSA) { RSA *rsa; if ((rsa = EVP_PKEY_get0_RSA(pkey)) == NULL) { al = SSL_AD_INTERNAL_ERROR; SSLerror(s, ERR_R_EVP_LIB); goto fatal_err; } verify = RSA_verify(NID_md5_sha1, s->s3->hs.tls12.cert_verify, MD5_DIGEST_LENGTH + SHA_DIGEST_LENGTH, CBS_data(&signature), CBS_len(&signature), rsa); if (verify < 0) { al = SSL_AD_DECRYPT_ERROR; SSLerror(s, SSL_R_BAD_RSA_DECRYPT); goto fatal_err; } if (verify == 0) { al = SSL_AD_DECRYPT_ERROR; SSLerror(s, SSL_R_BAD_RSA_SIGNATURE); goto fatal_err; } } else if (EVP_PKEY_id(pkey) == EVP_PKEY_EC) { EC_KEY *eckey; if ((eckey = EVP_PKEY_get0_EC_KEY(pkey)) == NULL) { al = SSL_AD_INTERNAL_ERROR; SSLerror(s, ERR_R_EVP_LIB); goto fatal_err; } verify = ECDSA_verify(0, &(s->s3->hs.tls12.cert_verify[MD5_DIGEST_LENGTH]), SHA_DIGEST_LENGTH, CBS_data(&signature), CBS_len(&signature), eckey); if (verify <= 0) { al = SSL_AD_DECRYPT_ERROR; SSLerror(s, SSL_R_BAD_ECDSA_SIGNATURE); goto fatal_err; } } else { SSLerror(s, ERR_R_INTERNAL_ERROR); al = SSL_AD_UNSUPPORTED_CERTIFICATE; goto fatal_err; } ret = 1; if (0) { decode_err: al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_PACKET_LENGTH); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); } end: tls1_transcript_free(s); err: EVP_MD_CTX_free(mctx); return (ret); } static int ssl3_get_client_certificate(SSL *s) { CBS cbs, cert_list, cert_data; STACK_OF(X509) *certs = NULL; X509 *cert = NULL; const uint8_t *p; int al, ret; if ((ret = ssl3_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, -1, s->max_cert_list)) <= 0) return ret; ret = -1; if (s->s3->hs.tls12.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto fatal_err; } /* * If we asked for a client certificate and the client has none, * it must respond with a certificate list of length zero. */ if (s->s3->hs.tls12.cert_request != 0) { SSLerror(s, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST); al = SSL_AD_UNEXPECTED_MESSAGE; goto fatal_err; } s->s3->hs.tls12.reuse_message = 1; return (1); } if (s->s3->hs.tls12.message_type != SSL3_MT_CERTIFICATE) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerror(s, SSL_R_WRONG_MESSAGE_TYPE); goto fatal_err; } if (s->init_num < 0) goto decode_err; CBS_init(&cbs, s->init_msg, s->init_num); if (!CBS_get_u24_length_prefixed(&cbs, &cert_list)) goto decode_err; if (CBS_len(&cbs) != 0) goto decode_err; /* * A TLS client must send an empty certificate list, if no suitable * certificate is available (rather than omitting the Certificate * handshake message) - see RFC 5246 section 7.4.6. */ if (CBS_len(&cert_list) == 0) { if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { SSLerror(s, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto fatal_err; } /* No client certificate so free transcript. */ tls1_transcript_free(s); goto done; } if ((certs = sk_X509_new_null()) == NULL) { SSLerror(s, ERR_R_MALLOC_FAILURE); goto err; } while (CBS_len(&cert_list) > 0) { if (!CBS_get_u24_length_prefixed(&cert_list, &cert_data)) goto decode_err; p = CBS_data(&cert_data); if ((cert = d2i_X509(NULL, &p, CBS_len(&cert_data))) == NULL) { SSLerror(s, ERR_R_ASN1_LIB); goto err; } if (p != CBS_data(&cert_data) + CBS_len(&cert_data)) goto decode_err; if (!sk_X509_push(certs, cert)) { SSLerror(s, ERR_R_MALLOC_FAILURE); goto err; } cert = NULL; } if (ssl_verify_cert_chain(s, certs) <= 0) { al = ssl_verify_alarm_type(s->verify_result); SSLerror(s, SSL_R_NO_CERTIFICATE_RETURNED); goto fatal_err; } s->session->verify_result = s->verify_result; ERR_clear_error(); if (!tls_process_peer_certs(s, certs)) goto err; done: ret = 1; if (0) { decode_err: al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_PACKET_LENGTH); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); } err: sk_X509_pop_free(certs, X509_free); X509_free(cert); return (ret); } static int ssl3_send_server_certificate(SSL *s) { CBB cbb, server_cert; SSL_CERT_PKEY *cpk; /* * Server Certificate - RFC 5246, section 7.4.2. */ memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_CERT_A) { if ((cpk = ssl_get_server_send_pkey(s)) == NULL) { SSLerror(s, ERR_R_INTERNAL_ERROR); return (0); } if (!ssl3_handshake_msg_start(s, &cbb, &server_cert, SSL3_MT_CERTIFICATE)) goto err; if (!ssl3_output_cert_chain(s, &server_cert, cpk)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_CERT_B; } /* SSL3_ST_SW_CERT_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (0); } /* send a new session ticket (not necessarily for a new session) */ static int ssl3_send_newsession_ticket(SSL *s) { CBB cbb, session_ticket, ticket; SSL_CTX *tctx = s->initial_ctx; size_t enc_session_len, enc_session_max_len, hmac_len; size_t session_len = 0; unsigned char *enc_session = NULL, *session = NULL; unsigned char iv[EVP_MAX_IV_LENGTH]; unsigned char key_name[16]; unsigned char *hmac; unsigned int hlen; EVP_CIPHER_CTX *ctx = NULL; HMAC_CTX *hctx = NULL; int iv_len, len; /* * New Session Ticket - RFC 5077, section 3.3. */ memset(&cbb, 0, sizeof(cbb)); if ((ctx = EVP_CIPHER_CTX_new()) == NULL) goto err; if ((hctx = HMAC_CTX_new()) == NULL) goto err; if (s->s3->hs.state == SSL3_ST_SW_SESSION_TICKET_A) { if (!ssl3_handshake_msg_start(s, &cbb, &session_ticket, SSL3_MT_NEWSESSION_TICKET)) goto err; if (!SSL_SESSION_ticket(s->session, &session, &session_len)) goto err; if (session_len > 0xffff) goto err; /* * Initialize HMAC and cipher contexts. If callback is present * it does all the work, otherwise use generated values from * parent context. */ if (tctx->tlsext_ticket_key_cb != NULL) { if (tctx->tlsext_ticket_key_cb(s, key_name, iv, ctx, hctx, 1) < 0) goto err; } else { arc4random_buf(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, EVP_sha256(), NULL); memcpy(key_name, tctx->tlsext_tick_key_name, 16); } /* Encrypt the session state. */ enc_session_max_len = session_len + EVP_MAX_BLOCK_LENGTH; if ((enc_session = calloc(1, enc_session_max_len)) == NULL) goto err; enc_session_len = 0; if (!EVP_EncryptUpdate(ctx, enc_session, &len, session, session_len)) goto err; enc_session_len += len; if (!EVP_EncryptFinal_ex(ctx, enc_session + enc_session_len, &len)) goto err; enc_session_len += len; if (enc_session_len > enc_session_max_len) goto err; /* Generate the HMAC. */ if (!HMAC_Update(hctx, key_name, sizeof(key_name))) goto err; if (!HMAC_Update(hctx, iv, EVP_CIPHER_CTX_iv_length(ctx))) goto err; if (!HMAC_Update(hctx, enc_session, enc_session_len)) goto err; if ((hmac_len = HMAC_size(hctx)) <= 0) goto err; /* * 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. */ if (!CBB_add_u32(&session_ticket, s->hit ? 0 : s->session->timeout)) goto err; if (!CBB_add_u16_length_prefixed(&session_ticket, &ticket)) goto err; if (!CBB_add_bytes(&ticket, key_name, sizeof(key_name))) goto err; if ((iv_len = EVP_CIPHER_CTX_iv_length(ctx)) < 0) goto err; if (!CBB_add_bytes(&ticket, iv, iv_len)) goto err; if (!CBB_add_bytes(&ticket, enc_session, enc_session_len)) goto err; if (!CBB_add_space(&ticket, &hmac, hmac_len)) goto err; if (!HMAC_Final(hctx, hmac, &hlen)) goto err; if (hlen != hmac_len) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_SESSION_TICKET_B; } EVP_CIPHER_CTX_free(ctx); HMAC_CTX_free(hctx); freezero(session, session_len); free(enc_session); /* SSL3_ST_SW_SESSION_TICKET_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); EVP_CIPHER_CTX_free(ctx); HMAC_CTX_free(hctx); freezero(session, session_len); free(enc_session); return (-1); } static int ssl3_send_cert_status(SSL *s) { CBB cbb, certstatus, ocspresp; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_CERT_STATUS_A) { if (!ssl3_handshake_msg_start(s, &cbb, &certstatus, SSL3_MT_CERTIFICATE_STATUS)) goto err; if (!CBB_add_u8(&certstatus, s->tlsext_status_type)) goto err; if (!CBB_add_u24_length_prefixed(&certstatus, &ocspresp)) goto err; if (!CBB_add_bytes(&ocspresp, s->tlsext_ocsp_resp, s->tlsext_ocsp_resp_len)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_CERT_STATUS_B; } /* SSL3_ST_SW_CERT_STATUS_B */ return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); } static int ssl3_send_server_change_cipher_spec(SSL *s) { size_t outlen; CBB cbb; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_CHANGE_A) { if (!CBB_init_fixed(&cbb, s->init_buf->data, s->init_buf->length)) goto err; if (!CBB_add_u8(&cbb, SSL3_MT_CCS)) goto err; if (!CBB_finish(&cbb, NULL, &outlen)) goto err; if (outlen > INT_MAX) goto err; s->init_num = (int)outlen; s->init_off = 0; if (SSL_is_dtls(s)) { s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, s->d1->handshake_write_seq, 0, 0); dtls1_buffer_message(s, 1); } s->s3->hs.state = SSL3_ST_SW_CHANGE_B; } /* SSL3_ST_SW_CHANGE_B */ return ssl3_record_write(s, SSL3_RT_CHANGE_CIPHER_SPEC); err: CBB_cleanup(&cbb); return -1; } static int ssl3_get_client_finished(SSL *s) { int al, md_len, ret; CBS cbs; /* should actually be 36+4 :-) */ if ((ret = ssl3_get_message(s, SSL3_ST_SR_FINISHED_A, SSL3_ST_SR_FINISHED_B, SSL3_MT_FINISHED, 64)) <= 0) return ret; /* If this occurs, we have missed a message */ if (!s->s3->change_cipher_spec) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerror(s, SSL_R_GOT_A_FIN_BEFORE_A_CCS); goto fatal_err; } s->s3->change_cipher_spec = 0; md_len = TLS1_FINISH_MAC_LENGTH; if (s->init_num < 0) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_DIGEST_LENGTH); goto fatal_err; } CBS_init(&cbs, s->init_msg, s->init_num); if (s->s3->hs.peer_finished_len != md_len || CBS_len(&cbs) != md_len) { al = SSL_AD_DECODE_ERROR; SSLerror(s, SSL_R_BAD_DIGEST_LENGTH); goto fatal_err; } if (!CBS_mem_equal(&cbs, s->s3->hs.peer_finished, CBS_len(&cbs))) { al = SSL_AD_DECRYPT_ERROR; SSLerror(s, SSL_R_DIGEST_CHECK_FAILED); goto fatal_err; } /* Copy finished so we can use it for renegotiation checks. */ OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE); memcpy(s->s3->previous_client_finished, s->s3->hs.peer_finished, md_len); s->s3->previous_client_finished_len = md_len; return (1); fatal_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); return (0); } static int ssl3_send_server_finished(SSL *s) { CBB cbb, finished; memset(&cbb, 0, sizeof(cbb)); if (s->s3->hs.state == SSL3_ST_SW_FINISHED_A) { if (!tls12_derive_finished(s)) goto err; /* Copy finished so we can use it for renegotiation checks. */ memcpy(s->s3->previous_server_finished, s->s3->hs.finished, s->s3->hs.finished_len); s->s3->previous_server_finished_len = s->s3->hs.finished_len; if (!ssl3_handshake_msg_start(s, &cbb, &finished, SSL3_MT_FINISHED)) goto err; if (!CBB_add_bytes(&finished, s->s3->hs.finished, s->s3->hs.finished_len)) goto err; if (!ssl3_handshake_msg_finish(s, &cbb)) goto err; s->s3->hs.state = SSL3_ST_SW_FINISHED_B; } return (ssl3_handshake_write(s)); err: CBB_cleanup(&cbb); return (-1); }