/* 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 "ssl_locl.h" #include "../crypto/internal.h" #include "../crypto/dh/internal.h" /* INITIAL_SNIFF_BUFFER_SIZE is the number of bytes read in the initial sniff * buffer. */ #define INITIAL_SNIFF_BUFFER_SIZE 8 int ssl3_accept(SSL *s) { BUF_MEM *buf = NULL; unsigned long alg_a; void (*cb)(const SSL *ssl, int type, int val) = NULL; int ret = -1; int new_state, state, skip = 0; assert(s->handshake_func == ssl3_accept); assert(s->server); assert(!SSL_IS_DTLS(s)); ERR_clear_error(); ERR_clear_system_error(); if (s->info_callback != NULL) { cb = s->info_callback; } else if (s->ctx->info_callback != NULL) { cb = s->ctx->info_callback; } s->in_handshake++; if (s->cert == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_accept, SSL_R_NO_CERTIFICATE_SET); return -1; } for (;;) { state = s->state; switch (s->state) { case SSL_ST_RENEGOTIATE: /* This state is the renegotiate entry point. It sends a HelloRequest * and nothing else. */ s->renegotiate = 1; if (cb != NULL) { cb(s, SSL_CB_HANDSHAKE_START, 1); } if (s->init_buf == NULL) { buf = BUF_MEM_new(); if (!buf || !BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) { ret = -1; goto end; } s->init_buf = buf; buf = NULL; } s->init_num = 0; if (!ssl3_setup_buffers(s)) { ret = -1; goto end; } if (!s->s3->send_connection_binding && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) { /* Server attempting to renegotiate with client that doesn't support * secure renegotiation. */ OPENSSL_PUT_ERROR(SSL, ssl3_accept, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); ret = -1; goto end; } s->ctx->stats.sess_accept_renegotiate++; s->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; ret = ssl3_send_hello_request(s); if (ret <= 0) { goto end; } s->s3->tmp.next_state = SSL3_ST_SW_HELLO_REQ_C; s->state = SSL3_ST_SW_FLUSH; s->init_num = 0; if (!ssl3_init_finished_mac(s)) { OPENSSL_PUT_ERROR(SSL, ssl3_accept, ERR_R_INTERNAL_ERROR); ret = -1; goto end; } break; case SSL3_ST_SW_HELLO_REQ_C: s->state = SSL_ST_OK; break; case SSL_ST_ACCEPT: case SSL_ST_BEFORE | SSL_ST_ACCEPT: /* This state is the entry point for the handshake itself (initial and * renegotiation). */ if (cb != NULL) { cb(s, SSL_CB_HANDSHAKE_START, 1); } if (s->init_buf == NULL) { buf = BUF_MEM_new(); if (!buf || !BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) { ret = -1; goto end; } s->init_buf = buf; buf = NULL; } s->init_num = 0; if (!ssl3_init_finished_mac(s)) { OPENSSL_PUT_ERROR(SSL, ssl3_accept, ERR_R_INTERNAL_ERROR); ret = -1; goto end; } if (!s->s3->have_version) { /* This is the initial handshake. The record layer has not been * initialized yet. Sniff for a V2ClientHello before reading a * ClientHello normally. */ assert(s->s3->rbuf.buf == NULL); assert(s->s3->wbuf.buf == NULL); s->state = SSL3_ST_SR_INITIAL_BYTES; } else { /* Enable a write buffer. This groups handshake messages within a * flight into a single write. */ if (!ssl3_setup_buffers(s) || !ssl_init_wbio_buffer(s, 1)) { ret = -1; goto end; } s->state = SSL3_ST_SR_CLNT_HELLO_A; } s->ctx->stats.sess_accept++; break; case SSL3_ST_SR_INITIAL_BYTES: ret = ssl3_get_initial_bytes(s); if (ret <= 0) { goto end; } /* ssl3_get_initial_bytes sets s->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(s); if (ret <= 0) { goto end; } s->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: case SSL3_ST_SR_CLNT_HELLO_D: s->shutdown = 0; ret = ssl3_get_client_hello(s); if (ret <= 0) { goto end; } s->renegotiate = 2; s->state = SSL3_ST_SW_SRVR_HELLO_A; s->init_num = 0; break; case SSL3_ST_SW_SRVR_HELLO_A: case SSL3_ST_SW_SRVR_HELLO_B: ret = ssl3_send_server_hello(s); if (ret <= 0) { goto end; } if (s->hit) { if (s->tlsext_ticket_expected) { s->state = SSL3_ST_SW_SESSION_TICKET_A; } else { s->state = SSL3_ST_SW_CHANGE_A; } } else { s->state = SSL3_ST_SW_CERT_A; } s->init_num = 0; break; case SSL3_ST_SW_CERT_A: case SSL3_ST_SW_CERT_B: if (ssl_cipher_has_server_public_key(s->s3->tmp.new_cipher)) { ret = ssl3_send_server_certificate(s); if (ret <= 0) { goto end; } if (s->s3->tmp.certificate_status_expected) { s->state = SSL3_ST_SW_CERT_STATUS_A; } else { s->state = SSL3_ST_SW_KEY_EXCH_A; } } else { skip = 1; s->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_a = s->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(s->s3->tmp.new_cipher) || ((alg_a & SSL_aPSK) && s->psk_identity_hint)) { ret = ssl3_send_server_key_exchange(s); if (ret <= 0) { goto end; } } else { skip = 1; } s->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: if (/* don't request cert unless asked for it: */ !(s->verify_mode & SSL_VERIFY_PEER) || /* Don't request a certificate if an obc was presented */ ((s->verify_mode & SSL_VERIFY_PEER_IF_NO_OBC) && s->s3->tlsext_channel_id_valid) || /* if SSL_VERIFY_CLIENT_ONCE is set, * don't request cert during re-negotiation: */ ((s->session->peer != NULL) && (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) || /* never request cert in anonymous ciphersuites * (see section "Certificate request" in SSL 3 drafts * and in RFC 2246): */ ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) && /* ... except when the application insists on verification * (against the specs, but s3_clnt.c accepts this for SSL 3) */ !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) || /* With normal PSK Certificates and * Certificate Requests are omitted */ (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) { /* no cert request */ skip = 1; s->s3->tmp.cert_request = 0; s->state = SSL3_ST_SW_SRVR_DONE_A; if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, free_handshake_buffer)) { return -1; } } else { s->s3->tmp.cert_request = 1; ret = ssl3_send_certificate_request(s); if (ret <= 0) { goto end; } s->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: ret = ssl3_send_server_done(s); if (ret <= 0) { goto end; } s->s3->tmp.next_state = SSL3_ST_SR_CERT_A; s->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) { ret = -1; goto end; } s->rwstate = SSL_NOTHING; s->state = s->s3->tmp.next_state; break; case SSL3_ST_SR_CERT_A: case SSL3_ST_SR_CERT_B: if (s->s3->tmp.cert_request) { ret = ssl3_get_client_certificate(s); if (ret <= 0) { goto end; } } s->init_num = 0; s->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; } s->state = SSL3_ST_SR_CERT_VRFY_A; s->init_num = 0; break; case SSL3_ST_SR_CERT_VRFY_A: case SSL3_ST_SR_CERT_VRFY_B: ret = ssl3_get_cert_verify(s); if (ret <= 0) { goto end; } s->state = SSL3_ST_SR_CHANGE; s->init_num = 0; break; case SSL3_ST_SR_CHANGE: { char next_proto_neg = 0; char channel_id = 0; next_proto_neg = s->s3->next_proto_neg_seen; channel_id = s->s3->tlsext_channel_id_valid; /* At this point, the next message must be entirely behind a * ChangeCipherSpec. */ if (!ssl3_expect_change_cipher_spec(s)) { ret = -1; goto end; } if (next_proto_neg) { s->state = SSL3_ST_SR_NEXT_PROTO_A; } else if (channel_id) { s->state = SSL3_ST_SR_CHANNEL_ID_A; } else { s->state = SSL3_ST_SR_FINISHED_A; } break; } case SSL3_ST_SR_NEXT_PROTO_A: case SSL3_ST_SR_NEXT_PROTO_B: ret = ssl3_get_next_proto(s); if (ret <= 0) { goto end; } s->init_num = 0; if (s->s3->tlsext_channel_id_valid) { s->state = SSL3_ST_SR_CHANNEL_ID_A; } else { s->state = SSL3_ST_SR_FINISHED_A; } break; case SSL3_ST_SR_CHANNEL_ID_A: case SSL3_ST_SR_CHANNEL_ID_B: ret = ssl3_get_channel_id(s); if (ret <= 0) { goto end; } s->init_num = 0; s->state = SSL3_ST_SR_FINISHED_A; break; case SSL3_ST_SR_FINISHED_A: case SSL3_ST_SR_FINISHED_B: ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A, SSL3_ST_SR_FINISHED_B); if (ret <= 0) { goto end; } if (s->hit) { s->state = SSL_ST_OK; } else if (s->tlsext_ticket_expected) { s->state = SSL3_ST_SW_SESSION_TICKET_A; } else { s->state = SSL3_ST_SW_CHANGE_A; } /* If this is a full handshake with ChannelID then record the hashshake * hashes in |s->session| in case we need them to verify a ChannelID * signature on a resumption of this session in the future. */ if (!s->hit && s->s3->tlsext_channel_id_new) { ret = tls1_record_handshake_hashes_for_channel_id(s); if (ret <= 0) { goto end; } } s->init_num = 0; break; case SSL3_ST_SW_SESSION_TICKET_A: case SSL3_ST_SW_SESSION_TICKET_B: ret = ssl3_send_new_session_ticket(s); if (ret <= 0) { goto end; } s->state = SSL3_ST_SW_CHANGE_A; s->init_num = 0; break; case SSL3_ST_SW_CHANGE_A: case SSL3_ST_SW_CHANGE_B: s->session->cipher = s->s3->tmp.new_cipher; if (!s->enc_method->setup_key_block(s)) { ret = -1; goto end; } ret = ssl3_send_change_cipher_spec(s, SSL3_ST_SW_CHANGE_A, SSL3_ST_SW_CHANGE_B); if (ret <= 0) { goto end; } s->state = SSL3_ST_SW_FINISHED_A; s->init_num = 0; if (!s->enc_method->change_cipher_state( s, 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(s, SSL3_ST_SW_FINISHED_A, SSL3_ST_SW_FINISHED_B, s->enc_method->server_finished_label, s->enc_method->server_finished_label_len); if (ret <= 0) { goto end; } s->state = SSL3_ST_SW_FLUSH; if (s->hit) { s->s3->tmp.next_state = SSL3_ST_SR_CHANGE; } else { s->s3->tmp.next_state = SSL_ST_OK; } s->init_num = 0; break; case SSL_ST_OK: /* clean a few things up */ ssl3_cleanup_key_block(s); BUF_MEM_free(s->init_buf); s->init_buf = NULL; /* remove buffering on output */ ssl_free_wbio_buffer(s); s->init_num = 0; /* If we aren't retaining peer certificates then we can discard it * now. */ if (s->session->peer && s->ctx->retain_only_sha256_of_client_certs) { X509_free(s->session->peer); s->session->peer = NULL; } if (s->renegotiate == 2) { /* skipped if we just sent a HelloRequest */ s->renegotiate = 0; s->new_session = 0; ssl_update_cache(s, SSL_SESS_CACHE_SERVER); s->ctx->stats.sess_accept_good++; if (cb != NULL) { cb(s, SSL_CB_HANDSHAKE_DONE, 1); } } ret = 1; goto end; default: OPENSSL_PUT_ERROR(SSL, ssl3_accept, SSL_R_UNKNOWN_STATE); ret = -1; goto end; } if (!s->s3->tmp.reuse_message && !skip && cb != NULL && s->state != state) { new_state = s->state; s->state = state; cb(s, SSL_CB_ACCEPT_LOOP, 1); s->state = new_state; } skip = 0; } end: s->in_handshake--; if (buf != NULL) { BUF_MEM_free(buf); } if (cb != NULL) { cb(s, SSL_CB_ACCEPT_EXIT, ret); } return ret; } static int ssl3_read_sniff_buffer(SSL *s, size_t n) { if (s->s3->sniff_buffer == NULL) { s->s3->sniff_buffer = BUF_MEM_new(); } if (s->s3->sniff_buffer == NULL || !BUF_MEM_grow(s->s3->sniff_buffer, n)) { return -1; } while (s->s3->sniff_buffer_len < n) { int ret; s->rwstate = SSL_READING; ret = BIO_read(s->rbio, s->s3->sniff_buffer->data + s->s3->sniff_buffer_len, n - s->s3->sniff_buffer_len); if (ret <= 0) { return ret; } s->rwstate = SSL_NOTHING; s->s3->sniff_buffer_len += ret; } return 1; } int ssl3_get_initial_bytes(SSL *s) { int ret; const uint8_t *p; /* Read the first 8 bytes. To recognize a ClientHello or V2ClientHello only * needs the first 6 bytes, but 8 is needed to recognize CONNECT below. */ ret = ssl3_read_sniff_buffer(s, INITIAL_SNIFF_BUFFER_SIZE); if (ret <= 0) { return ret; } assert(s->s3->sniff_buffer_len >= INITIAL_SNIFF_BUFFER_SIZE); p = (const uint8_t *)s->s3->sniff_buffer->data; /* 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, ssl3_get_initial_bytes, SSL_R_HTTP_REQUEST); return -1; } if (strncmp("CONNECT ", (const char *)p, 8) == 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_initial_bytes, SSL_R_HTTPS_PROXY_REQUEST); return -1; } /* Determine if this is a ClientHello or V2ClientHello. */ if ((p[0] & 0x80) && p[2] == SSL2_MT_CLIENT_HELLO && p[3] >= SSL3_VERSION_MAJOR) { /* This is a V2ClientHello. */ s->state = SSL3_ST_SR_V2_CLIENT_HELLO; return 1; } if (p[0] == SSL3_RT_HANDSHAKE && p[1] >= SSL3_VERSION_MAJOR && p[5] == SSL3_MT_CLIENT_HELLO) { /* This is a ClientHello. Initialize the record layer with the already * consumed data and continue the handshake. */ if (!ssl3_setup_buffers(s) || !ssl_init_wbio_buffer(s, 1)) { return -1; } assert(s->rstate == SSL_ST_READ_HEADER); memcpy(s->s3->rbuf.buf, p, s->s3->sniff_buffer_len); s->s3->rbuf.offset = 0; s->s3->rbuf.left = s->s3->sniff_buffer_len; s->packet_length = 0; BUF_MEM_free(s->s3->sniff_buffer); s->s3->sniff_buffer = NULL; s->s3->sniff_buffer_len = 0; s->state = SSL3_ST_SR_CLNT_HELLO_A; return 1; } OPENSSL_PUT_ERROR(SSL, ssl3_get_initial_bytes, SSL_R_UNKNOWN_PROTOCOL); return -1; } int ssl3_get_v2_client_hello(SSL *s) { const uint8_t *p; int ret; CBS v2_client_hello, cipher_specs, session_id, challenge; size_t msg_length, rand_len, 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]; /* Read the remainder of the V2ClientHello. We have previously read 8 bytes * in ssl3_get_initial_bytes. */ assert(s->s3->sniff_buffer_len >= INITIAL_SNIFF_BUFFER_SIZE); p = (const uint8_t *)s->s3->sniff_buffer->data; msg_length = ((p[0] & 0x7f) << 8) | p[1]; if (msg_length > (1024 * 4)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_v2_client_hello, SSL_R_RECORD_TOO_LARGE); return -1; } if (msg_length < INITIAL_SNIFF_BUFFER_SIZE - 2) { /* Reject lengths that are too short early. We have already read 8 bytes, * so we should not attempt to process an (invalid) V2ClientHello which * would be shorter than that. */ OPENSSL_PUT_ERROR(SSL, ssl3_get_v2_client_hello, SSL_R_RECORD_LENGTH_MISMATCH); return -1; } ret = ssl3_read_sniff_buffer(s, msg_length + 2); if (ret <= 0) { return ret; } assert(s->s3->sniff_buffer_len == msg_length + 2); CBS_init(&v2_client_hello, (const uint8_t *)s->s3->sniff_buffer->data + 2, msg_length); /* The V2ClientHello without the length is incorporated into the Finished * hash. */ ssl3_finish_mac(s, CBS_data(&v2_client_hello), CBS_len(&v2_client_hello)); if (s->msg_callback) { s->msg_callback(0, SSL2_VERSION, 0, CBS_data(&v2_client_hello), CBS_len(&v2_client_hello), s, s->msg_callback_arg); } 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, ssl3_get_v2_client_hello, 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. */ if (!CBB_init_fixed(&client_hello, (uint8_t *)s->init_buf->data, s->init_buf->max)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_v2_client_hello, ERR_R_MALLOC_FAILURE); return -1; } if (!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, ssl3_get_v2_client_hello, ERR_R_INTERNAL_ERROR); 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, ssl3_get_v2_client_hello, 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, ssl3_get_v2_client_hello, 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, &len)) { CBB_cleanup(&client_hello); OPENSSL_PUT_ERROR(SSL, ssl3_get_v2_client_hello, ERR_R_INTERNAL_ERROR); return -1; } /* Mark the message for "re"-use by the version-specific method. */ s->s3->tmp.reuse_message = 1; s->s3->tmp.message_type = SSL3_MT_CLIENT_HELLO; /* The handshake message header is 4 bytes. */ s->s3->tmp.message_size = len - 4; /* Initialize the record layer. */ if (!ssl3_setup_buffers(s) || !ssl_init_wbio_buffer(s, 1)) { return -1; } /* Drop the sniff buffer. */ BUF_MEM_free(s->s3->sniff_buffer); s->s3->sniff_buffer = NULL; s->s3->sniff_buffer_len = 0; return 1; } int ssl3_send_hello_request(SSL *s) { if (s->state == SSL3_ST_SW_HELLO_REQ_A) { ssl_set_handshake_header(s, SSL3_MT_HELLO_REQUEST, 0); s->state = SSL3_ST_SW_HELLO_REQ_B; } /* SSL3_ST_SW_HELLO_REQ_B */ return ssl_do_write(s); } int ssl3_get_client_hello(SSL *s) { int i, 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; /* 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 (s->state) { case SSL3_ST_SR_CLNT_HELLO_A: case SSL3_ST_SR_CLNT_HELLO_B: n = s->method->ssl_get_message( s, SSL3_ST_SR_CLNT_HELLO_A, SSL3_ST_SR_CLNT_HELLO_B, SSL3_MT_CLIENT_HELLO, SSL3_RT_MAX_PLAIN_LENGTH, SSL_GET_MESSAGE_HASH_MESSAGE, &ok); if (!ok) { return n; } /* If we require cookies and this ClientHello doesn't contain one, just * return since we do not want to allocate any memory yet. So check * cookie length... */ if (SSL_IS_DTLS(s) && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE)) { uint8_t cookie_length; CBS_init(&client_hello, s->init_msg, n); if (!CBS_skip(&client_hello, 2 + SSL3_RANDOM_SIZE) || !CBS_get_u8_length_prefixed(&client_hello, &session_id) || !CBS_get_u8(&client_hello, &cookie_length)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_DECODE_ERROR); goto f_err; } if (cookie_length == 0) { return 1; } } s->state = SSL3_ST_SR_CLNT_HELLO_C; /* fallthrough */ case SSL3_ST_SR_CLNT_HELLO_C: case SSL3_ST_SR_CLNT_HELLO_D: /* 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 = s->init_num; memset(&early_ctx, 0, sizeof(early_ctx)); early_ctx.ssl = s; early_ctx.client_hello = s->init_msg; early_ctx.client_hello_len = n; if (!ssl_early_callback_init(&early_ctx)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_CLIENTHELLO_PARSE_FAILED); goto f_err; } if (s->state == SSL3_ST_SR_CLNT_HELLO_C && s->ctx->select_certificate_cb != NULL) { s->state = SSL3_ST_SR_CLNT_HELLO_D; switch (s->ctx->select_certificate_cb(&early_ctx)) { case 0: s->rwstate = SSL_CERTIFICATE_SELECTION_PENDING; goto err; case -1: /* Connection rejected. */ al = SSL_AD_ACCESS_DENIED; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_CONNECTION_REJECTED); goto f_err; default: /* fallthrough */; } } s->state = SSL3_ST_SR_CLNT_HELLO_D; break; default: OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_UNKNOWN_STATE); return -1; } CBS_init(&client_hello, s->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, ssl3_get_client_hello, 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) */ s->client_version = client_version; /* Load the client random. */ memcpy(s->s3->client_random, CBS_data(&client_random), SSL3_RANDOM_SIZE); if (SSL_IS_DTLS(s)) { 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, ssl3_get_client_hello, SSL_R_DECODE_ERROR); goto f_err; } /* Verify the cookie if appropriate option is set. */ if ((SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) && CBS_len(&cookie) > 0) { if (s->ctx->app_verify_cookie_cb != NULL) { if (s->ctx->app_verify_cookie_cb(s, CBS_data(&cookie), CBS_len(&cookie)) == 0) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_COOKIE_MISMATCH); goto f_err; } /* else cookie verification succeeded */ } else if (!CBS_mem_equal(&cookie, s->d1->cookie, s->d1->cookie_len)) { /* default verification */ al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_COOKIE_MISMATCH); goto f_err; } /* Set to -2 so if successful we return 2 and don't send * HelloVerifyRequest. */ ret = -2; } } if (!s->s3->have_version) { /* Select version to use */ uint16_t version = ssl3_get_mutual_version(s, client_version); if (version == 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_UNSUPPORTED_PROTOCOL); s->version = s->client_version; al = SSL_AD_PROTOCOL_VERSION; goto f_err; } s->version = version; s->enc_method = ssl3_get_enc_method(version); assert(s->enc_method != NULL); /* At this point, the connection's version is known and |s->version| is * fixed. Begin enforcing the record-layer version. */ s->s3->have_version = 1; } else if (SSL_IS_DTLS(s) ? (s->client_version > s->version) : (s->client_version < s->version)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_WRONG_VERSION_NUMBER); al = SSL_AD_PROTOCOL_VERSION; goto f_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 { i = ssl_get_prev_session(s, &early_ctx); if (i == PENDING_SESSION) { s->rwstate = SSL_PENDING_SESSION; goto err; } else if (i == -1) { goto err; } /* Only resume if the session's version matches the negotiated version: * most clients do not accept a mismatch. */ if (i == 1 && s->version == s->session->ssl_version) { s->hit = 1; } else { /* No session was found or it was unacceptable. */ if (!ssl_get_new_session(s, 1)) { goto err; } } } if (!CBS_get_u16_length_prefixed(&client_hello, &cipher_suites) || !CBS_get_u8_length_prefixed(&client_hello, &compression_methods) || CBS_len(&compression_methods) == 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_DECODE_ERROR); goto f_err; } /* TODO(davidben): Per spec, cipher_suites can never be empty (specified at * the ClientHello structure level). This logic allows it to be empty if * resuming a session. Can we always require non-empty? If a client sends * empty cipher_suites because it's resuming a session, it could always fail * to resume a session, so it's unlikely to actually work. */ 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; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_NO_CIPHERS_SPECIFIED); goto f_err; } ciphers = ssl_bytes_to_cipher_list(s, &cipher_suites); if (ciphers == NULL) { goto err; } /* If it is a hit, check that the cipher is in the list. */ if (s->hit && CBS_len(&cipher_suites) > 0) { size_t j; int found_cipher = 0; unsigned long id = s->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, ssl3_get_client_hello, 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, ssl3_get_client_hello, SSL_R_NO_COMPRESSION_SPECIFIED); goto f_err; } /* TLS extensions. */ if (s->version >= SSL3_VERSION && !ssl_parse_clienthello_tlsext(s, &client_hello)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, 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, ssl3_get_client_hello, SSL_R_BAD_PACKET_LENGTH); goto f_err; } /* Given ciphers and SSL_get_ciphers, we must pick a cipher */ if (!s->hit) { if (ciphers == NULL) { al = SSL_AD_ILLEGAL_PARAMETER; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_NO_CIPHERS_PASSED); goto f_err; } /* Let cert callback update server certificates if required */ if (s->cert->cert_cb) { int rv = s->cert->cert_cb(s, s->cert->cert_cb_arg); if (rv == 0) { al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_CERT_CB_ERROR); goto f_err; } if (rv < 0) { s->rwstate = SSL_X509_LOOKUP; goto err; } s->rwstate = SSL_NOTHING; } c = ssl3_choose_cipher(s, ciphers, ssl_get_cipher_preferences(s)); if (c == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_NO_SHARED_CIPHER); goto f_err; } s->s3->tmp.new_cipher = c; } else { /* Session-id reuse */ s->s3->tmp.new_cipher = s->session->cipher; } if ((!SSL_USE_SIGALGS(s) || !(s->verify_mode & SSL_VERIFY_PEER)) && !ssl3_digest_cached_records(s, free_handshake_buffer)) { goto f_err; } /* 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 * s->session - The ssl session has been setup. * s->hit - session reuse flag * s->tmp.new_cipher - the new cipher to use. */ if (ret < 0) { ret = -ret; } if (0) { f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); } err: if (ciphers != NULL) { sk_SSL_CIPHER_free(ciphers); } return ret; } int ssl3_send_server_hello(SSL *s) { uint8_t *buf; uint8_t *p, *d; int sl; unsigned long l; if (s->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 (s->s3->tlsext_channel_id_valid && (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kEECDH) == 0) { s->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 (s->hit && s->s3->tlsext_channel_id_new && s->session->original_handshake_hash_len == 0) { s->s3->tlsext_channel_id_valid = 0; } buf = (uint8_t *)s->init_buf->data; /* Do the message type and length last */ d = p = ssl_handshake_start(s); *(p++) = s->version >> 8; *(p++) = s->version & 0xff; /* Random stuff */ if (!ssl_fill_hello_random(s, 1, s->s3->server_random, SSL3_RANDOM_SIZE)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_hello, ERR_R_INTERNAL_ERROR); return -1; } memcpy(p, s->s3->server_random, SSL3_RANDOM_SIZE); p += SSL3_RANDOM_SIZE; /* 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 > (int)sizeof(s->session->session_id)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_hello, ERR_R_INTERNAL_ERROR); return -1; } *(p++) = sl; memcpy(p, s->session->session_id, sl); p += sl; /* put the cipher */ s2n(ssl3_get_cipher_value(s->s3->tmp.new_cipher), p); /* put the compression method */ *(p++) = 0; if (ssl_prepare_serverhello_tlsext(s) <= 0) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_hello, SSL_R_SERVERHELLO_TLSEXT); return -1; } p = ssl_add_serverhello_tlsext(s, p, buf + SSL3_RT_MAX_PLAIN_LENGTH); if (p == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_hello, ERR_R_INTERNAL_ERROR); return -1; } /* do the header */ l = (p - d); ssl_set_handshake_header(s, SSL3_MT_SERVER_HELLO, l); s->state = SSL3_ST_SW_SRVR_HELLO_B; } /* SSL3_ST_SW_SRVR_HELLO_B */ return ssl_do_write(s); } int ssl3_send_server_done(SSL *s) { if (s->state == SSL3_ST_SW_SRVR_DONE_A) { ssl_set_handshake_header(s, SSL3_MT_SERVER_DONE, 0); s->state = SSL3_ST_SW_SRVR_DONE_B; } /* SSL3_ST_SW_SRVR_DONE_B */ return ssl_do_write(s); } int ssl3_send_server_key_exchange(SSL *s) { DH *dh = NULL, *dhp; EC_KEY *ecdh = NULL, *ecdhp; uint8_t *encodedPoint = NULL; int encodedlen = 0; uint16_t curve_id = 0; BN_CTX *bn_ctx = NULL; const char *psk_identity_hint = NULL; size_t psk_identity_hint_len = 0; EVP_PKEY *pkey; uint8_t *p, *d; int al, i; unsigned long alg_k; unsigned long alg_a; int n; CERT *cert; BIGNUM *r[4]; int nr[4], kn; BUF_MEM *buf; EVP_MD_CTX md_ctx; EVP_MD_CTX_init(&md_ctx); if (s->state == SSL3_ST_SW_KEY_EXCH_A) { alg_k = s->s3->tmp.new_cipher->algorithm_mkey; alg_a = s->s3->tmp.new_cipher->algorithm_auth; cert = s->cert; buf = s->init_buf; r[0] = r[1] = r[2] = r[3] = NULL; n = 0; if (alg_a & SSL_aPSK) { /* size for PSK identity hint */ psk_identity_hint = s->psk_identity_hint; if (psk_identity_hint) { psk_identity_hint_len = strlen(psk_identity_hint); } else { psk_identity_hint_len = 0; } n += 2 + psk_identity_hint_len; } if (alg_k & SSL_kEDH) { dhp = cert->dh_tmp; if (dhp == NULL && s->cert->dh_tmp_cb != NULL) { dhp = s->cert->dh_tmp_cb(s, 0, 1024); } if (dhp == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, SSL_R_MISSING_TMP_DH_KEY); goto f_err; } if (s->s3->tmp.dh != NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_INTERNAL_ERROR); goto err; } dh = DHparams_dup(dhp); if (dh == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_DH_LIB); goto err; } s->s3->tmp.dh = dh; if (dhp->pub_key == NULL || dhp->priv_key == NULL || (s->options & SSL_OP_SINGLE_DH_USE)) { if (!DH_generate_key(dh)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_DH_LIB); goto err; } } else { dh->pub_key = BN_dup(dhp->pub_key); dh->priv_key = BN_dup(dhp->priv_key); if (dh->pub_key == NULL || dh->priv_key == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_DH_LIB); goto err; } } r[0] = dh->p; r[1] = dh->g; r[2] = dh->pub_key; } else if (alg_k & SSL_kEECDH) { const EC_GROUP *group; ecdhp = cert->ecdh_tmp; if (s->cert->ecdh_tmp_auto) { /* Get NID of appropriate shared curve */ int nid = tls1_get_shared_curve(s); if (nid != NID_undef) { ecdhp = EC_KEY_new_by_curve_name(nid); } } else if (ecdhp == NULL && s->cert->ecdh_tmp_cb) { ecdhp = s->cert->ecdh_tmp_cb(s, 0, 1024); } if (ecdhp == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, SSL_R_MISSING_TMP_ECDH_KEY); goto f_err; } if (s->s3->tmp.ecdh != NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_INTERNAL_ERROR); goto err; } /* Duplicate the ECDH structure. */ if (ecdhp == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_ECDH_LIB); goto err; } if (s->cert->ecdh_tmp_auto) { ecdh = ecdhp; } else { ecdh = EC_KEY_dup(ecdhp); if (ecdh == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_ECDH_LIB); goto err; } } s->s3->tmp.ecdh = ecdh; if (EC_KEY_get0_public_key(ecdh) == NULL || EC_KEY_get0_private_key(ecdh) == NULL || (s->options & SSL_OP_SINGLE_ECDH_USE)) { if (!EC_KEY_generate_key(ecdh)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_ECDH_LIB); goto err; } } group = EC_KEY_get0_group(ecdh); if (group == NULL || EC_KEY_get0_public_key(ecdh) == NULL || EC_KEY_get0_private_key(ecdh) == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_ECDH_LIB); goto err; } /* We only support ephemeral ECDH keys over named (not generic) curves. */ if (!tls1_ec_nid2curve_id(&curve_id, EC_GROUP_get_curve_name(group))) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, SSL_R_UNSUPPORTED_ELLIPTIC_CURVE); goto err; } /* Encode the public key. First check the size of encoding and allocate * memory accordingly. */ encodedlen = EC_POINT_point2oct(group, EC_KEY_get0_public_key(ecdh), POINT_CONVERSION_UNCOMPRESSED, NULL, 0, NULL); encodedPoint = (uint8_t *)OPENSSL_malloc(encodedlen * sizeof(uint8_t)); bn_ctx = BN_CTX_new(); if (encodedPoint == NULL || bn_ctx == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } encodedlen = EC_POINT_point2oct(group, EC_KEY_get0_public_key(ecdh), POINT_CONVERSION_UNCOMPRESSED, encodedPoint, encodedlen, bn_ctx); if (encodedlen == 0) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_ECDH_LIB); goto err; } BN_CTX_free(bn_ctx); bn_ctx = NULL; /* We only support named (not generic) curves in ECDH ephemeral key * exchanges. In this situation, we need four additional bytes to encode * the entire ServerECDHParams structure. */ n += 4 + encodedlen; /* We'll generate the serverKeyExchange message explicitly so we can set * these to NULLs */ r[0] = NULL; r[1] = NULL; r[2] = NULL; r[3] = NULL; } else if (!(alg_k & SSL_kPSK)) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, SSL_R_UNKNOWN_KEY_EXCHANGE_TYPE); goto f_err; } for (i = 0; i < 4 && r[i] != NULL; i++) { nr[i] = BN_num_bytes(r[i]); n += 2 + nr[i]; } if (ssl_cipher_has_server_public_key(s->s3->tmp.new_cipher)) { pkey = ssl_get_sign_pkey(s, s->s3->tmp.new_cipher); if (pkey == NULL) { al = SSL_AD_DECODE_ERROR; goto f_err; } kn = EVP_PKEY_size(pkey); } else { pkey = NULL; kn = 0; } if (!BUF_MEM_grow_clean(buf, n + SSL_HM_HEADER_LENGTH(s) + kn)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_LIB_BUF); goto err; } d = p = ssl_handshake_start(s); for (i = 0; i < 4 && r[i] != NULL; i++) { s2n(nr[i], p); BN_bn2bin(r[i], p); p += nr[i]; } /* Note: ECDHE PSK ciphersuites use SSL_kEECDH and SSL_aPSK. When one of * them is used, the server key exchange record needs to have both the * psk_identity_hint and the ServerECDHParams. */ if (alg_a & SSL_aPSK) { /* copy PSK identity hint (if provided) */ s2n(psk_identity_hint_len, p); if (psk_identity_hint_len > 0) { memcpy(p, psk_identity_hint, psk_identity_hint_len); p += psk_identity_hint_len; } } if (alg_k & SSL_kEECDH) { /* We only support named (not generic) curves. In this situation, the * serverKeyExchange message has: * [1 byte CurveType], [2 byte CurveName] * [1 byte length of encoded point], followed by * the actual encoded point itself. */ *(p++) = NAMED_CURVE_TYPE; *(p++) = (uint8_t)(curve_id >> 8); *(p++) = (uint8_t)(curve_id & 0xff); *(p++) = encodedlen; memcpy(p, encodedPoint, encodedlen); p += encodedlen; OPENSSL_free(encodedPoint); encodedPoint = NULL; } /* not anonymous */ if (pkey != NULL) { /* n is the length of the params, they start at &(d[4]) and p points to * the space at the end. */ const EVP_MD *md; size_t sig_len = EVP_PKEY_size(pkey); /* Determine signature algorithm. */ if (SSL_USE_SIGALGS(s)) { md = tls1_choose_signing_digest(s, pkey); if (!tls12_get_sigandhash(p, pkey, md)) { /* Should never happen */ al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_R_INTERNAL_ERROR); goto f_err; } p += 2; } else if (pkey->type == EVP_PKEY_RSA) { md = EVP_md5_sha1(); } else { md = EVP_sha1(); } if (!EVP_DigestSignInit(&md_ctx, NULL, md, NULL, pkey) || !EVP_DigestSignUpdate(&md_ctx, s->s3->client_random, SSL3_RANDOM_SIZE) || !EVP_DigestSignUpdate(&md_ctx, s->s3->server_random, SSL3_RANDOM_SIZE) || !EVP_DigestSignUpdate(&md_ctx, d, n) || !EVP_DigestSignFinal(&md_ctx, &p[2], &sig_len)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_LIB_EVP); goto err; } s2n(sig_len, p); n += sig_len + 2; if (SSL_USE_SIGALGS(s)) { n += 2; } } ssl_set_handshake_header(s, SSL3_MT_SERVER_KEY_EXCHANGE, n); } s->state = SSL3_ST_SW_KEY_EXCH_B; EVP_MD_CTX_cleanup(&md_ctx); return ssl_do_write(s); f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); err: if (encodedPoint != NULL) { OPENSSL_free(encodedPoint); } BN_CTX_free(bn_ctx); EVP_MD_CTX_cleanup(&md_ctx); return -1; } int ssl3_send_certificate_request(SSL *s) { 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 (s->state == SSL3_ST_SW_CERT_REQ_A) { buf = s->init_buf; d = p = ssl_handshake_start(s); /* get the list of acceptable cert types */ p++; n = ssl3_get_req_cert_type(s, p); d[0] = n; p += n; n++; if (SSL_USE_SIGALGS(s)) { const uint8_t *psigs; nl = tls12_get_psigalgs(s, &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(s); 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(s) + n + j + 2)) { OPENSSL_PUT_ERROR(SSL, ssl3_send_certificate_request, ERR_R_BUF_LIB); goto err; } p = ssl_handshake_start(s) + n; s2n(j, p); i2d_X509_NAME(name, &p); n += 2 + j; nl += 2 + j; } } /* else no CA names */ p = ssl_handshake_start(s) + off; s2n(nl, p); ssl_set_handshake_header(s, SSL3_MT_CERTIFICATE_REQUEST, n); s->state = SSL3_ST_SW_CERT_REQ_B; } /* SSL3_ST_SW_CERT_REQ_B */ return ssl_do_write(s); err: return -1; } int ssl3_get_client_key_exchange(SSL *s) { int al, ok; long n; CBS client_key_exchange; unsigned long alg_k; unsigned long alg_a; uint8_t *premaster_secret = NULL; size_t premaster_secret_len = 0; RSA *rsa = NULL; uint8_t *decrypt_buf = NULL; EVP_PKEY *pkey = NULL; BIGNUM *pub = NULL; DH *dh_srvr; EC_KEY *srvr_ecdh = NULL; EVP_PKEY *clnt_pub_pkey = NULL; EC_POINT *clnt_ecpoint = NULL; BN_CTX *bn_ctx = NULL; unsigned int psk_len = 0; uint8_t psk[PSK_MAX_PSK_LEN]; n = s->method->ssl_get_message(s, SSL3_ST_SR_KEY_EXCH_A, SSL3_ST_SR_KEY_EXCH_B, SSL3_MT_CLIENT_KEY_EXCHANGE, 2048, /* ??? */ SSL_GET_MESSAGE_HASH_MESSAGE, &ok); if (!ok) { return n; } CBS_init(&client_key_exchange, s->init_msg, n); alg_k = s->s3->tmp.new_cipher->algorithm_mkey; alg_a = s->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, ssl3_get_client_key_exchange, SSL_R_DECODE_ERROR); al = SSL_AD_DECODE_ERROR; goto f_err; } if (s->psk_server_callback == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, 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, ssl3_get_client_key_exchange, SSL_R_DATA_LENGTH_TOO_LONG); al = SSL_AD_ILLEGAL_PARAMETER; goto f_err; } if (!CBS_strdup(&psk_identity, &s->session->psk_identity)) { al = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto f_err; } /* Look up the key for the identity. */ psk_len = s->psk_server_callback(s, s->session->psk_identity, psk, sizeof(psk)); if (psk_len > PSK_MAX_PSK_LEN) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, 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, ssl3_get_client_key_exchange, 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) { CBS encrypted_premaster_secret; uint8_t rand_premaster_secret[SSL_MAX_MASTER_KEY_LENGTH]; uint8_t good; size_t rsa_size, decrypt_len, premaster_index, j; pkey = s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey; if (pkey == NULL || pkey->type != EVP_PKEY_RSA || pkey->pkey.rsa == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_MISSING_RSA_CERTIFICATE); goto f_err; } rsa = pkey->pkey.rsa; /* TLS and [incidentally] DTLS{0xFEFF} */ if (s->version > SSL3_VERSION) { CBS copy = client_key_exchange; if (!CBS_get_u16_length_prefixed(&client_key_exchange, &encrypted_premaster_secret) || CBS_len(&client_key_exchange) != 0) { if (!(s->options & SSL_OP_TLS_D5_BUG)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_TLS_RSA_ENCRYPTED_VALUE_LENGTH_IS_WRONG); goto f_err; } else { encrypted_premaster_secret = copy; } } } else { encrypted_premaster_secret = client_key_exchange; } /* Reject overly short RSA keys because we want to be sure that the buffer * size makes it safe to iterate over the entire size of a premaster secret * (SSL_MAX_MASTER_KEY_LENGTH). The actual expected size is larger due to * RSA padding, but the bound is sufficient to be safe. */ rsa_size = RSA_size(rsa); if (rsa_size < SSL_MAX_MASTER_KEY_LENGTH) { al = SSL_AD_DECRYPT_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_DECRYPTION_FAILED); goto f_err; } /* We must not leak whether a decryption failure occurs because of * Bleichenbacher's attack on PKCS #1 v1.5 RSA padding (see RFC 2246, * section 7.4.7.1). The code follows that advice of the TLS RFC and * generates a random premaster secret for the case that the decrypt fails. * See https://tools.ietf.org/html/rfc5246#section-7.4.7.1 */ if (!RAND_bytes(rand_premaster_secret, sizeof(rand_premaster_secret))) { goto err; } /* Allocate a buffer large enough for an RSA decryption. */ decrypt_buf = OPENSSL_malloc(rsa_size); if (decrypt_buf == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } /* Decrypt with no padding. PKCS#1 padding will be removed as part of the * timing-sensitive code below. */ if (!RSA_decrypt(rsa, &decrypt_len, decrypt_buf, rsa_size, CBS_data(&encrypted_premaster_secret), CBS_len(&encrypted_premaster_secret), RSA_NO_PADDING)) { goto err; } if (decrypt_len != rsa_size) { /* This should never happen, but do a check so we do not read * uninitialized memory. */ OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_INTERNAL_ERROR); goto err; } /* Remove the PKCS#1 padding and adjust |decrypt_len| as appropriate. * |good| will be 0xff if the premaster is acceptable and zero otherwise. * */ good = constant_time_eq_int_8(RSA_message_index_PKCS1_type_2( decrypt_buf, decrypt_len, &premaster_index), 1); decrypt_len = decrypt_len - premaster_index; /* decrypt_len should be SSL_MAX_MASTER_KEY_LENGTH. */ good &= constant_time_eq_8(decrypt_len, SSL_MAX_MASTER_KEY_LENGTH); /* Copy over the unpadded premaster. Whatever the value of * |decrypt_good_mask|, copy as if the premaster were the right length. It * is important the memory access pattern be constant. */ premaster_secret = BUF_memdup(decrypt_buf + (rsa_size - SSL_MAX_MASTER_KEY_LENGTH), SSL_MAX_MASTER_KEY_LENGTH); if (premaster_secret == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } OPENSSL_free(decrypt_buf); decrypt_buf = NULL; /* If the version in the decrypted pre-master secret is correct then * version_good will be 0xff, otherwise it'll be zero. 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". Thus version checks are done in constant time * and are treated like any other decryption error. */ good &= constant_time_eq_8(premaster_secret[0], (unsigned)(s->client_version >> 8)); good &= constant_time_eq_8(premaster_secret[1], (unsigned)(s->client_version & 0xff)); /* Now copy rand_premaster_secret over premaster_secret using * decrypt_good_mask. */ for (j = 0; j < sizeof(rand_premaster_secret); j++) { premaster_secret[j] = constant_time_select_8(good, premaster_secret[j], rand_premaster_secret[j]); } premaster_secret_len = sizeof(rand_premaster_secret); } else if (alg_k & SSL_kEDH) { CBS dh_Yc; int dh_len; if (!CBS_get_u16_length_prefixed(&client_key_exchange, &dh_Yc) || CBS_len(&dh_Yc) == 0 || CBS_len(&client_key_exchange) != 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_DH_PUBLIC_VALUE_LENGTH_IS_WRONG); al = SSL_R_DECODE_ERROR; goto f_err; } if (s->s3->tmp.dh == NULL) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_MISSING_TMP_DH_KEY); goto f_err; } dh_srvr = s->s3->tmp.dh; pub = BN_bin2bn(CBS_data(&dh_Yc), CBS_len(&dh_Yc), NULL); if (pub == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_BN_LIB); goto err; } /* Allocate a buffer for the premaster secret. */ premaster_secret = OPENSSL_malloc(DH_size(dh_srvr)); if (premaster_secret == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); BN_clear_free(pub); goto err; } dh_len = DH_compute_key(premaster_secret, pub, dh_srvr); if (dh_len <= 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_DH_LIB); BN_clear_free(pub); goto err; } DH_free(s->s3->tmp.dh); s->s3->tmp.dh = NULL; BN_clear_free(pub); pub = NULL; premaster_secret_len = dh_len; } else if (alg_k & SSL_kEECDH) { int field_size = 0, ecdh_len; const EC_KEY *tkey; const EC_GROUP *group; const BIGNUM *priv_key; CBS ecdh_Yc; /* initialize structures for server's ECDH key pair */ srvr_ecdh = EC_KEY_new(); if (srvr_ecdh == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } /* Use the ephermeral values we saved when generating the ServerKeyExchange * msg. */ tkey = s->s3->tmp.ecdh; group = EC_KEY_get0_group(tkey); priv_key = EC_KEY_get0_private_key(tkey); if (!EC_KEY_set_group(srvr_ecdh, group) || !EC_KEY_set_private_key(srvr_ecdh, priv_key)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_EC_LIB); goto err; } /* Let's get client's public key */ clnt_ecpoint = EC_POINT_new(group); if (clnt_ecpoint == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } /* Get client's public key from encoded point in the ClientKeyExchange * message. */ if (!CBS_get_u8_length_prefixed(&client_key_exchange, &ecdh_Yc) || CBS_len(&client_key_exchange) != 0) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, SSL_R_DECODE_ERROR); goto f_err; } bn_ctx = BN_CTX_new(); if (bn_ctx == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } if (!EC_POINT_oct2point(group, clnt_ecpoint, CBS_data(&ecdh_Yc), CBS_len(&ecdh_Yc), bn_ctx)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_EC_LIB); goto err; } /* Allocate a buffer for both the secret and the PSK. */ field_size = EC_GROUP_get_degree(group); if (field_size <= 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_ECDH_LIB); goto err; } ecdh_len = (field_size + 7) / 8; premaster_secret = OPENSSL_malloc(ecdh_len); if (premaster_secret == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } /* Compute the shared pre-master secret */ ecdh_len = ECDH_compute_key(premaster_secret, ecdh_len, clnt_ecpoint, srvr_ecdh, NULL); if (ecdh_len <= 0) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_ECDH_LIB); goto err; } EVP_PKEY_free(clnt_pub_pkey); clnt_pub_pkey = NULL; EC_POINT_free(clnt_ecpoint); clnt_ecpoint = NULL; EC_KEY_free(srvr_ecdh); srvr_ecdh = NULL; BN_CTX_free(bn_ctx); bn_ctx = NULL; EC_KEY_free(s->s3->tmp.ecdh); s->s3->tmp.ecdh = NULL; premaster_secret_len = ecdh_len; } 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, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } memset(premaster_secret, 0, premaster_secret_len); } else { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, 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; if (!CBB_init(&new_premaster, 2 + psk_len + 2 + premaster_secret_len)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_key_exchange, ERR_R_MALLOC_FAILURE); goto err; } if (!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, ssl3_get_client_key_exchange, ERR_R_INTERNAL_ERROR); 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 */ s->session->master_key_length = s->enc_method->generate_master_secret( s, s->session->master_key, premaster_secret, premaster_secret_len); if (s->session->master_key_length == 0) { goto err; } s->session->extended_master_secret = s->s3->tmp.extended_master_secret; OPENSSL_cleanse(premaster_secret, premaster_secret_len); OPENSSL_free(premaster_secret); return 1; f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); err: if (premaster_secret) { if (premaster_secret_len) { OPENSSL_cleanse(premaster_secret, premaster_secret_len); } OPENSSL_free(premaster_secret); } if (decrypt_buf) { OPENSSL_free(decrypt_buf); } EVP_PKEY_free(clnt_pub_pkey); EC_POINT_free(clnt_ecpoint); if (srvr_ecdh != NULL) { EC_KEY_free(srvr_ecdh); } BN_CTX_free(bn_ctx); return -1; } int ssl3_get_cert_verify(SSL *s) { int al, ok, ret = 0; long n; CBS certificate_verify, signature; X509 *peer = s->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) { if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, free_handshake_buffer)) { return -1; } return 1; } n = s->method->ssl_get_message( s, SSL3_ST_SR_CERT_VRFY_A, SSL3_ST_SR_CERT_VRFY_B, SSL3_MT_CERTIFICATE_VERIFY, SSL3_RT_MAX_PLAIN_LENGTH, SSL_GET_MESSAGE_DONT_HASH_MESSAGE, &ok); if (!ok) { return n; } /* Filter out unsupported certificate types. */ pkey = X509_get_pubkey(peer); 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, ssl3_get_cert_verify, SSL_R_PEER_ERROR_UNSUPPORTED_CERTIFICATE_TYPE); goto f_err; } CBS_init(&certificate_verify, s->init_msg, n); /* Determine the digest type if needbe. */ if (SSL_USE_SIGALGS(s) && !tls12_check_peer_sigalg(&md, &al, s, &certificate_verify, pkey)) { goto f_err; } /* Compute the digest. */ if (!ssl3_cert_verify_hash(s, digest, &digest_length, &md, pkey)) { goto err; } /* The handshake buffer is no longer necessary, and we may hash the current * message.*/ if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, free_handshake_buffer)) { goto err; } ssl3_hash_current_message(s); /* 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, ssl3_get_cert_verify, SSL_R_DECODE_ERROR); goto f_err; } pctx = EVP_PKEY_CTX_new(pkey, NULL); if (pctx == NULL) { goto err; } if (!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)) { al = SSL_AD_DECRYPT_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_cert_verify, SSL_R_BAD_SIGNATURE); goto f_err; } ret = 1; if (0) { f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); } err: EVP_PKEY_CTX_free(pctx); EVP_PKEY_free(pkey); return ret; } int ssl3_get_client_certificate(SSL *s) { int i, 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; n = s->method->ssl_get_message(s, SSL3_ST_SR_CERT_A, SSL3_ST_SR_CERT_B, -1, s->max_cert_list, SSL_GET_MESSAGE_HASH_MESSAGE, &ok); if (!ok) { return n; } if (s->s3->tmp.message_type == SSL3_MT_CLIENT_KEY_EXCHANGE) { if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto f_err; } /* If tls asked for a client cert, the client must return a 0 list */ if (s->version > SSL3_VERSION && s->s3->tmp.cert_request) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_TLS_PEER_DID_NOT_RESPOND_WITH_CERTIFICATE_LIST); al = SSL_AD_UNEXPECTED_MESSAGE; goto f_err; } s->s3->tmp.reuse_message = 1; return 1; } if (s->s3->tmp.message_type != SSL3_MT_CERTIFICATE) { al = SSL_AD_UNEXPECTED_MESSAGE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_WRONG_MESSAGE_TYPE); goto f_err; } CBS_init(&certificate_msg, s->init_msg, n); sk = sk_X509_new_null(); if (sk == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, 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, ssl3_get_client_certificate, 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, ssl3_get_client_certificate, SSL_R_DECODE_ERROR); goto f_err; } if (is_first_certificate && s->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(s->session->peer_sha256, &sha256); s->session->peer_sha256_valid = 1; } is_first_certificate = 0; data = CBS_data(&certificate); x = d2i_X509(NULL, &data, CBS_len(&certificate)); if (x == NULL) { al = SSL_AD_BAD_CERTIFICATE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, ERR_R_ASN1_LIB); goto f_err; } if (data != CBS_data(&certificate) + CBS_len(&certificate)) { al = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_CERT_LENGTH_MISMATCH); goto f_err; } if (!sk_X509_push(sk, x)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, ERR_R_MALLOC_FAILURE); goto err; } x = NULL; } if (sk_X509_num(sk) <= 0) { /* TLS does not mind 0 certs returned */ if (s->version == SSL3_VERSION) { al = SSL_AD_HANDSHAKE_FAILURE; OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_NO_CERTIFICATES_RETURNED); goto f_err; } /* Fail for TLS only if we required a certificate */ else if ((s->verify_mode & SSL_VERIFY_PEER) && (s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); al = SSL_AD_HANDSHAKE_FAILURE; goto f_err; } /* No client certificate so digest cached records */ if (s->s3->handshake_buffer && !ssl3_digest_cached_records(s, free_handshake_buffer)) { al = SSL_AD_INTERNAL_ERROR; goto f_err; } } else { i = ssl_verify_cert_chain(s, sk); if (i <= 0) { al = ssl_verify_alarm_type(s->verify_result); OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, SSL_R_CERTIFICATE_VERIFY_FAILED); goto f_err; } } if (s->session->peer != NULL) { /* This should not be needed */ X509_free(s->session->peer); } s->session->peer = sk_X509_shift(sk); s->session->verify_result = s->verify_result; /* With the current implementation, sess_cert will always be NULL when we * arrive here. */ if (s->session->sess_cert == NULL) { s->session->sess_cert = ssl_sess_cert_new(); if (s->session->sess_cert == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, ERR_R_MALLOC_FAILURE); goto err; } } if (s->session->sess_cert->cert_chain != NULL) { sk_X509_pop_free(s->session->sess_cert->cert_chain, X509_free); } s->session->sess_cert->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(s, SSL3_AL_FATAL, al); } err: if (x != NULL) { X509_free(x); } if (sk != NULL) { sk_X509_pop_free(sk, X509_free); } return ret; } int ssl3_send_server_certificate(SSL *s) { CERT_PKEY *cpk; if (s->state == SSL3_ST_SW_CERT_A) { cpk = ssl_get_server_send_pkey(s); if (cpk == NULL) { OPENSSL_PUT_ERROR(SSL, ssl3_send_server_certificate, ERR_R_INTERNAL_ERROR); return 0; } ssl3_output_cert_chain(s, cpk); s->state = SSL3_ST_SW_CERT_B; } /* SSL3_ST_SW_CERT_B */ return ssl_do_write(s); } /* send a new session ticket (not necessarily for a new session) */ int ssl3_send_new_session_ticket(SSL *s) { if (s->state == SSL3_ST_SW_SESSION_TICKET_A) { uint8_t *session; size_t session_len; uint8_t *p, *macstart; int len; unsigned int hlen; EVP_CIPHER_CTX ctx; HMAC_CTX hctx; SSL_CTX *tctx = s->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(s->session, &session, &session_len)) { return -1; } /* 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); p = ssl_handshake_start(s); /* 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(s); ssl_set_handshake_header(s, SSL3_MT_NEWSESSION_TICKET, len); s->state = SSL3_ST_SW_SESSION_TICKET_B; return ssl_do_write(s); } /* 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(s->init_buf, SSL_HM_HEADER_LENGTH(s) + 6 + max_ticket_overhead + session_len)) { OPENSSL_free(session); return -1; } p = ssl_handshake_start(s); EVP_CIPHER_CTX_init(&ctx); HMAC_CTX_init(&hctx); /* 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(s, key_name, iv, &ctx, &hctx, 1) < 0) { OPENSSL_free(session); EVP_CIPHER_CTX_cleanup(&ctx); HMAC_CTX_cleanup(&hctx); return -1; } } 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)) { OPENSSL_free(session); EVP_CIPHER_CTX_cleanup(&ctx); HMAC_CTX_cleanup(&hctx); return -1; } 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(s->hit ? 0 : s->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 */ EVP_EncryptUpdate(&ctx, p, &len, session, session_len); p += len; EVP_EncryptFinal_ex(&ctx, p, &len); p += len; EVP_CIPHER_CTX_cleanup(&ctx); HMAC_Update(&hctx, macstart, p - macstart); HMAC_Final(&hctx, p, &hlen); HMAC_CTX_cleanup(&hctx); p += hlen; /* Now write out lengths: p points to end of data written */ /* Total length */ len = p - ssl_handshake_start(s); /* Skip ticket lifetime hint */ p = ssl_handshake_start(s) + 4; s2n(len - 6, p); ssl_set_handshake_header(s, SSL3_MT_NEWSESSION_TICKET, len); s->state = SSL3_ST_SW_SESSION_TICKET_B; OPENSSL_free(session); } /* SSL3_ST_SW_SESSION_TICKET_B */ return ssl_do_write(s); } /* 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 *s) { 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 (!s->s3->next_proto_neg_seen) { OPENSSL_PUT_ERROR(SSL, ssl3_get_next_proto, SSL_R_GOT_NEXT_PROTO_WITHOUT_EXTENSION); return -1; } n = s->method->ssl_get_message(s, SSL3_ST_SR_NEXT_PROTO_A, SSL3_ST_SR_NEXT_PROTO_B, SSL3_MT_NEXT_PROTO, 514, /* See the payload format below */ SSL_GET_MESSAGE_HASH_MESSAGE, &ok); if (!ok) { return n; } /* s->state doesn't reflect whether ChangeCipherSpec has been received in * this handshake, but s->s3->change_cipher_spec does (will be reset by * ssl3_get_finished). * * TODO(davidben): Is this check now redundant with * SSL3_FLAGS_EXPECT_CCS? */ if (!s->s3->change_cipher_spec) { OPENSSL_PUT_ERROR(SSL, ssl3_get_next_proto, SSL_R_GOT_NEXT_PROTO_BEFORE_A_CCS); return -1; } CBS_init(&next_protocol, s->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, &s->next_proto_negotiated, &s->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 *s) { int ret = -1, ok; long n; EVP_MD_CTX md_ctx; uint8_t channel_id_hash[SHA256_DIGEST_LENGTH]; unsigned int channel_id_hash_len; const uint8_t *p; uint16_t extension_type, expected_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 = s->method->ssl_get_message( s, SSL3_ST_SR_CHANNEL_ID_A, SSL3_ST_SR_CHANNEL_ID_B, SSL3_MT_ENCRYPTED_EXTENSIONS, 2 + 2 + TLSEXT_CHANNEL_ID_SIZE, SSL_GET_MESSAGE_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. */ channel_id_hash_len = sizeof(channel_id_hash); EVP_MD_CTX_init(&md_ctx); if (!EVP_DigestInit_ex(&md_ctx, EVP_sha256(), NULL) || !tls1_channel_id_hash(&md_ctx, s) || !EVP_DigestFinal(&md_ctx, channel_id_hash, &channel_id_hash_len)) { EVP_MD_CTX_cleanup(&md_ctx); return -1; } EVP_MD_CTX_cleanup(&md_ctx); assert(channel_id_hash_len == SHA256_DIGEST_LENGTH); ssl3_hash_current_message(s); /* s->state doesn't reflect whether ChangeCipherSpec has been received in * this handshake, but s->s3->change_cipher_spec does (will be reset by * ssl3_get_finished). * * TODO(davidben): Is this check now redundant with SSL3_FLAGS_EXPECT_CCS? */ if (!s->s3->change_cipher_spec) { OPENSSL_PUT_ERROR(SSL, ssl3_get_channel_id, SSL_R_GOT_CHANNEL_ID_BEFORE_A_CCS); return -1; } CBS_init(&encrypted_extensions, s->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]; */ expected_extension_type = TLSEXT_TYPE_channel_id; if (s->s3->tlsext_channel_id_new) { expected_extension_type = TLSEXT_TYPE_channel_id_new; } if (!CBS_get_u16(&encrypted_extensions, &extension_type) || !CBS_get_u16_length_prefixed(&encrypted_extensions, &extension) || CBS_len(&encrypted_extensions) != 0 || extension_type != expected_extension_type || CBS_len(&extension) != TLSEXT_CHANNEL_ID_SIZE) { OPENSSL_PUT_ERROR(SSL, ssl3_get_channel_id, SSL_R_INVALID_MESSAGE); return -1; } p256 = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1); if (!p256) { OPENSSL_PUT_ERROR(SSL, ssl3_get_channel_id, SSL_R_NO_P256_SUPPORT); return -1; } BN_init(&x); BN_init(&y); sig.r = BN_new(); sig.s = BN_new(); 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, ssl3_get_channel_id, SSL_R_CHANNEL_ID_SIGNATURE_INVALID); s->s3->tlsext_channel_id_valid = 0; goto err; } memcpy(s->s3->tlsext_channel_id, p, 64); ret = 1; err: BN_free(&x); BN_free(&y); BN_free(sig.r); BN_free(sig.s); if (key) { EC_KEY_free(key); } if (point) { EC_POINT_free(point); } if (p256) { EC_GROUP_free(p256); } return ret; }