blob: 149d9e7bc26bb9dd81bcb73e0e2ba97cd12c14db [file] [log] [blame]
/* 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. */
#define NETSCAPE_HANG_BUG
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <openssl/bn.h>
#include <openssl/buf.h>
#include <openssl/bytestring.h>
#include <openssl/cipher.h>
#include <openssl/dh.h>
#include <openssl/ec.h>
#include <openssl/ecdsa.h>
#include <openssl/evp.h>
#include <openssl/hmac.h>
#include <openssl/md5.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/rand.h>
#include <openssl/sha.h>
#include <openssl/x509.h>
#include "ssl_locl.h"
#include "../crypto/dh/internal.h"
static const SSL_METHOD *ssl3_get_server_method(int ver)
{
switch (ver)
{
case TLS1_2_VERSION:
return TLSv1_2_server_method();
case TLS1_1_VERSION:
return TLSv1_1_server_method();
case TLS1_VERSION:
return TLSv1_server_method();
case SSL3_VERSION:
return SSLv3_server_method();
default:
return NULL;
}
}
IMPLEMENT_tls_meth_func(TLS1_2_VERSION, TLSv1_2_server_method,
ssl3_accept,
ssl_undefined_function,
ssl3_get_server_method,
TLSv1_2_enc_data)
IMPLEMENT_tls_meth_func(TLS1_1_VERSION, TLSv1_1_server_method,
ssl3_accept,
ssl_undefined_function,
ssl3_get_server_method,
TLSv1_1_enc_data)
IMPLEMENT_tls_meth_func(TLS1_VERSION, TLSv1_server_method,
ssl3_accept,
ssl_undefined_function,
ssl3_get_server_method,
TLSv1_enc_data)
IMPLEMENT_tls_meth_func(SSL3_VERSION, SSLv3_server_method,
ssl3_accept,
ssl_undefined_function,
ssl3_get_server_method,
SSLv3_enc_data)
int ssl3_accept(SSL *s)
{
BUF_MEM *buf;
unsigned long alg_a;
void (*cb)(const SSL *ssl,int type,int val)=NULL;
int ret= -1;
int new_state,state,skip=0;
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;
/* init things to blank */
s->in_handshake++;
if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
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:
s->renegotiate=1;
/* s->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;
if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
if ((s->version>>8) != 3)
{
OPENSSL_PUT_ERROR(SSL, ssl3_accept, ERR_R_INTERNAL_ERROR);
return -1;
}
s->type=SSL_ST_ACCEPT;
if (s->init_buf == NULL)
{
if ((buf=BUF_MEM_new()) == NULL)
{
ret= -1;
goto end;
}
if (!BUF_MEM_grow(buf,SSL3_RT_MAX_PLAIN_LENGTH))
{
ret= -1;
goto end;
}
s->init_buf=buf;
}
if (!ssl3_setup_buffers(s))
{
ret= -1;
goto end;
}
s->init_num=0;
if (s->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; }
ssl3_init_finished_mac(s);
s->state=SSL3_ST_SR_CLNT_HELLO_A;
s->ctx->stats.sess_accept++;
}
else 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;
}
else
{
/* s->state == SSL_ST_RENEGOTIATE,
* we will just send a HelloRequest */
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;
ssl3_init_finished_mac(s);
break;
case SSL3_ST_SW_HELLO_REQ_C:
s->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:
case SSL3_ST_SR_CLNT_HELLO_D:
s->shutdown=0;
ret=ssl3_get_client_hello(s);
if (ret == PENDING_SESSION) {
s->rwstate = SSL_PENDING_SESSION;
goto end;
}
if (ret == CERTIFICATE_SELECTION_PENDING)
{
s->rwstate = SSL_CERTIFICATE_SELECTION_PENDING;
goto end;
}
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->session->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)
if (!ssl3_digest_cached_records(s))
return -1;
}
else
{
s->s3->tmp.cert_request=1;
ret=ssl3_send_certificate_request(s);
if (ret <= 0) goto end;
#ifndef NETSCAPE_HANG_BUG
s->state=SSL3_ST_SW_SRVR_DONE_A;
#else
s->state=SSL3_ST_SW_FLUSH;
s->s3->tmp.next_state=SSL3_ST_SR_CERT_A;
#endif
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;
#if 0
// TODO(davidben): Implement OCSP stapling on the server.
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->state=SSL3_ST_SW_KEY_EXCH_A;
s->init_num=0;
break;
#endif
case SSL3_ST_SW_CHANGE_A:
case SSL3_ST_SW_CHANGE_B:
s->session->cipher=s->s3->tmp.new_cipher;
if (!s->method->ssl3_enc->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->method->ssl3_enc->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->method->ssl3_enc->server_finished_label,
s->method->ssl3_enc->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++;
/* s->server=1; */
s->handshake_func=ssl3_accept;
if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
}
ret = 1;
goto end;
/* break; */
default:
OPENSSL_PUT_ERROR(SSL, ssl3_accept, SSL_R_UNKNOWN_STATE);
ret= -1;
goto end;
/* break; */
}
if (!s->s3->tmp.reuse_message && !skip)
{
if (s->debug)
{
if ((ret=BIO_flush(s->wbio)) <= 0)
goto end;
}
if ((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:
/* BIO_flush(s->wbio); */
s->in_handshake--;
if (cb != NULL)
cb(s,SSL_CB_ACCEPT_EXIT,ret);
return(ret);
}
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:
s->first_packet=1;
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((int)n);
s->first_packet=0;
/* 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))
{
CBS session_id;
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)
{
int ret;
s->state = SSL3_ST_SR_CLNT_HELLO_D;
ret = s->ctx->select_certificate_cb(&early_ctx);
if (ret == 0)
return CERTIFICATE_SELECTION_PENDING;
else if (ret == -1)
{
/* Connection rejected. */
al = SSL_AD_ACCESS_DENIED;
OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_CONNECTION_REJECTED);
goto f_err;
}
}
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;
if (SSL_IS_DTLS(s) ? (s->client_version > s->version &&
s->method->version != DTLS_ANY_VERSION)
: (s->client_version < s->version))
{
OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_WRONG_VERSION_NUMBER);
if ((s->client_version>>8) == SSL3_VERSION_MAJOR &&
!s->enc_write_ctx && !s->write_hash)
{
/* similar to ssl3_get_record, send alert using remote version number */
s->version = s->client_version;
}
al = SSL_AD_PROTOCOL_VERSION;
goto f_err;
}
/* Load the client random. */
memcpy(s->s3->client_random, CBS_data(&client_random), SSL3_RANDOM_SIZE);
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 == 1)
{ /* previous session */
s->hit=1;
}
else if (i == -1)
goto err;
else if (i == PENDING_SESSION)
{
ret = PENDING_SESSION;
goto err;
}
else /* i == 0 */
{
if (!ssl_get_new_session(s,1))
goto err;
}
}
if (SSL_IS_DTLS(s))
{
CBS cookie;
/* TODO(davidben): The length check here is off. Per
* spec, the maximum cookie length is 32. However, the
* DTLS1_COOKIE_LENGTH check is checking against 256,
* not 32 (so it's actually redundant).
* 07a9d1a2c2b735cbc327065000b545deb5e136cf from
* OpenSSL switched this from 32 to 256. */
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->method->version == DTLS_ANY_VERSION)
{
/* Select version to use */
if (s->client_version <= DTLS1_2_VERSION &&
!(s->options & SSL_OP_NO_DTLSv1_2))
{
s->version = DTLS1_2_VERSION;
s->method = DTLSv1_2_server_method();
}
else if (s->client_version <= DTLS1_VERSION &&
!(s->options & SSL_OP_NO_DTLSv1))
{
s->version = DTLS1_VERSION;
s->method = DTLSv1_server_method();
}
else
{
OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_WRONG_VERSION_NUMBER);
s->version = s->client_version;
al = SSL_AD_PROTOCOL_VERSION;
goto f_err;
}
s->session->ssl_version = s->version;
}
}
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;
}
if (ssl_bytes_to_cipher_list(s, &cipher_suites, &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)
{
if (!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;
}
/* 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. */
{
unsigned char *pos;
pos=s->s3->server_random;
if (ssl_fill_hello_random(s, 1, pos, SSL3_RANDOM_SIZE) <= 0)
{
goto f_err;
}
}
if (!s->hit && s->version >= TLS1_VERSION && s->tls_session_secret_cb)
{
const SSL_CIPHER *pref_cipher=NULL;
s->session->master_key_length=sizeof(s->session->master_key);
if(s->tls_session_secret_cb(s, s->session->master_key, &s->session->master_key_length,
ciphers, &pref_cipher, s->tls_session_secret_cb_arg))
{
s->hit=1;
s->session->verify_result=X509_V_OK;
/* check if some cipher was preferred by call back */
pref_cipher=pref_cipher ? pref_cipher : ssl3_choose_cipher(s, ciphers, ssl_get_cipher_preferences(s));
if (pref_cipher == NULL)
{
al=SSL_AD_HANDSHAKE_FAILURE;
OPENSSL_PUT_ERROR(SSL, ssl3_get_client_hello, SSL_R_NO_SHARED_CIPHER);
goto f_err;
}
s->session->cipher=pref_cipher;
if (s->cipher_list)
ssl_cipher_preference_list_free(s->cipher_list);
if (s->cipher_list_by_id)
sk_SSL_CIPHER_free(s->cipher_list_by_id);
s->cipher_list = ssl_cipher_preference_list_from_ciphers(ciphers);
s->cipher_list_by_id = sk_SSL_CIPHER_dup(ciphers);
}
}
/* 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))
{
if (!ssl3_digest_cached_records(s))
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)
{
unsigned char *buf;
unsigned char *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 &&
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=(unsigned char *)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 */
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;
}
if ((p = ssl_add_serverhello_tlsext(s, p, buf+SSL3_RT_MAX_PLAIN_LENGTH)) == 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)
{
unsigned char *q;
int j,num;
unsigned char md_buf[MD5_DIGEST_LENGTH+SHA_DIGEST_LENGTH];
unsigned int u;
DH *dh=NULL,*dhp;
EC_KEY *ecdh=NULL, *ecdhp;
unsigned char *encodedPoint = NULL;
int encodedlen = 0;
int curve_id = 0;
BN_CTX *bn_ctx = NULL;
const char* psk_identity_hint = NULL;
size_t psk_identity_hint_len = 0;
EVP_PKEY *pkey;
const EVP_MD *md = NULL;
unsigned char *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->session->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;
}
if ((dh=DHparams_dup(dhp)) == 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 if ((ecdh = EC_KEY_dup(ecdhp)) == 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;
}
}
if (((group = EC_KEY_get0_group(ecdh)) == 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;
}
/* XXX: For now, we only support ephemeral ECDH
* keys over named (not generic) curves. For
* supported named curves, curve_id is non-zero.
*/
if ((curve_id =
tls1_ec_nid2curve_id(EC_GROUP_get_curve_name(group)))
== 0)
{
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 = (unsigned char *)
OPENSSL_malloc(encodedlen*sizeof(unsigned char));
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;
/* XXX: For now, 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))
{
if ((pkey=ssl_get_sign_pkey(s,s->s3->tmp.new_cipher,&md))
== 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)
{
/* XXX: For now, 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 += 1;
*p = 0;
p += 1;
*p = curve_id;
p += 1;
*p = encodedlen;
p += 1;
memcpy((unsigned char*)p,
(unsigned char *)encodedPoint,
encodedlen);
OPENSSL_free(encodedPoint);
encodedPoint = NULL;
p += encodedlen;
}
/* 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. */
if (pkey->type == EVP_PKEY_RSA && !SSL_USE_SIGALGS(s))
{
q=md_buf;
j=0;
for (num=2; num > 0; num--)
{
EVP_DigestInit_ex(&md_ctx,
(num == 2) ? EVP_md5() : EVP_sha1(), NULL);
EVP_DigestUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
EVP_DigestUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
EVP_DigestUpdate(&md_ctx,d,n);
EVP_DigestFinal_ex(&md_ctx,q,
(unsigned int *)&i);
q+=i;
j+=i;
}
if (RSA_sign(NID_md5_sha1, md_buf, j,
&(p[2]), &u, pkey->pkey.rsa) <= 0)
{
OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_LIB_RSA);
goto err;
}
s2n(u,p);
n+=u+2;
}
else
if (md)
{
/* send signature algorithm */
if (SSL_USE_SIGALGS(s))
{
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;
}
#ifdef SSL_DEBUG
fprintf(stderr, "Using hash %s\n",
EVP_MD_name(md));
#endif
EVP_SignInit_ex(&md_ctx, md, NULL);
EVP_SignUpdate(&md_ctx,&(s->s3->client_random[0]),SSL3_RANDOM_SIZE);
EVP_SignUpdate(&md_ctx,&(s->s3->server_random[0]),SSL3_RANDOM_SIZE);
EVP_SignUpdate(&md_ctx,d,n);
if (!EVP_SignFinal(&md_ctx,&(p[2]),
(unsigned int *)&i,pkey))
{
OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, ERR_LIB_EVP);
goto err;
}
s2n(i,p);
n+=i+2;
if (SSL_USE_SIGALGS(s))
n+= 2;
}
else
{
/* Is this error check actually needed? */
al=SSL_AD_HANDSHAKE_FAILURE;
OPENSSL_PUT_ERROR(SSL, ssl3_send_server_key_exchange, SSL_R_UNKNOWN_PKEY_TYPE);
goto f_err;
}
}
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)
{
unsigned char *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 unsigned char *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);
#ifdef NETSCAPE_HANG_BUG
if (!SSL_IS_DTLS(s))
{
if (!BUF_MEM_grow_clean(buf, s->init_num + 4))
{
OPENSSL_PUT_ERROR(SSL, ssl3_send_certificate_request, ERR_R_BUF_LIB);
goto err;
}
p=(unsigned char *)s->init_buf->data + s->init_num;
/* do the header */
*(p++)=SSL3_MT_SERVER_DONE;
*(p++)=0;
*(p++)=0;
*(p++)=0;
s->init_num += 4;
}
#endif
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;
unsigned char 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((int)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];
int decrypt_good_mask;
uint8_t version_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_pseudo_bytes(rand_premaster_secret,
sizeof(rand_premaster_secret)) <= 0)
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. decrypt_good_mask will be zero if the premaster
* if good and non-zero otherwise. */
decrypt_good_mask = RSA_message_index_PKCS1_type_2(
decrypt_buf, decrypt_len, &premaster_index);
decrypt_good_mask--;
decrypt_len = decrypt_len - premaster_index;
/* decrypt_len should be SSL_MAX_MASTER_KEY_LENGTH. */
decrypt_good_mask |= 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 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. */
version_good = premaster_secret[0] ^ (s->client_version>>8);
version_good |= premaster_secret[1] ^ (s->client_version&0xff);
/* If any bits in version_good are set then they'll poision
* decrypt_good_mask and cause rand_premaster_secret to be
* used. */
decrypt_good_mask |= version_good;
/* decrypt_good_mask will be zero iff decrypt_len ==
* SSL_MAX_MASTER_KEY_LENGTH and the version check passed. We
* fold the bottom 32 bits of it with an OR so that the LSB
* will be zero iff everything is good. This assumes that we'll
* never decrypt a value > 2**31 bytes, which seems safe. */
decrypt_good_mask |= decrypt_good_mask >> 16;
decrypt_good_mask |= decrypt_good_mask >> 8;
decrypt_good_mask |= decrypt_good_mask >> 4;
decrypt_good_mask |= decrypt_good_mask >> 2;
decrypt_good_mask |= decrypt_good_mask >> 1;
/* Now select only the LSB and subtract one. If decrypt_len ==
* SSL_MAX_MASTER_KEY_LENGTH and the version check passed then
* decrypt_good_mask will be all ones. Otherwise it'll be all
* zeros. */
decrypt_good_mask &= 1;
decrypt_good_mask--;
/* Now copy rand_premaster_secret over premaster_secret using
* decrypt_good_mask. */
for (j = 0; j < sizeof(rand_premaster_secret); j++)
{
premaster_secret[j] = (premaster_secret[j] & decrypt_good_mask) |
(rand_premaster_secret[j] & ~decrypt_good_mask);
}
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);
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 */
if ((srvr_ecdh = EC_KEY_new()) == 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 */
if ((clnt_ecpoint = EC_POINT_new(group)) == 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;
}
if ((bn_ctx = BN_CTX_new()) == 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);
EC_POINT_free(clnt_ecpoint);
EC_KEY_free(srvr_ecdh);
BN_CTX_free(bn_ctx);
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->method->ssl3_enc
->generate_master_secret(s,
s->session->master_key, premaster_secret, premaster_secret_len);
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))
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 (int)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))
{
if (!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))
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((int)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);
if ((sk=sk_X509_new_null()) == 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 (!CBS_skip(&certificate, data - CBS_data(&certificate)))
{
al = SSL_AD_INTERNAL_ERROR;
OPENSSL_PUT_ERROR(SSL, ssl3_get_client_certificate, ERR_R_INTERNAL_ERROR);
goto f_err;
}
if (CBS_len(&certificate) != 0)
{
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))
{
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)
{
unsigned char *p, *senc, *macstart;
const unsigned char *const_p;
int len, slen_full, slen;
SSL_SESSION *sess;
unsigned int hlen;
EVP_CIPHER_CTX ctx;
HMAC_CTX hctx;
SSL_CTX *tctx = s->initial_ctx;
unsigned char iv[EVP_MAX_IV_LENGTH];
unsigned char key_name[16];
/* get session encoding length */
slen_full = i2d_SSL_SESSION(s->session, NULL);
/* Some length values are 16 bits, so forget it if session is
* too long
*/
if (slen_full > 0xFF00)
return -1;
senc = OPENSSL_malloc(slen_full);
if (!senc)
return -1;
p = senc;
i2d_SSL_SESSION(s->session, &p);
/* create a fresh copy (not shared with other threads) to clean up */
const_p = senc;
sess = d2i_SSL_SESSION(NULL, &const_p, slen_full);
if (sess == NULL)
{
OPENSSL_free(senc);
return -1;
}
sess->session_id_length = 0; /* ID is irrelevant for the ticket */
slen = i2d_SSL_SESSION(sess, NULL);
if (slen > slen_full) /* shouldn't ever happen */
{
OPENSSL_free(senc);
return -1;
}
p = senc;
i2d_SSL_SESSION(sess, &p);
SSL_SESSION_free(sess);
/* Grow buffer if need be: the length calculation is as
* follows handshake_header_length +
* 4 (ticket lifetime hint) + 2 (ticket length) +
* 16 (key name) + max_iv_len (iv length) +
* session_length + max_enc_block_size (max encrypted session
* length) + max_md_size (HMAC).
*/
if (!BUF_MEM_grow(s->init_buf,
SSL_HM_HEADER_LENGTH(s) + 22 + EVP_MAX_IV_LENGTH +
EVP_MAX_BLOCK_LENGTH + EVP_MAX_MD_SIZE + slen))
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(senc);
return -1;
}
}
else
{
RAND_pseudo_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);
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, senc, slen);
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);
ssl_set_handshake_header(s, SSL3_MT_NEWSESSION_TICKET, len);
/* Skip ticket lifetime hint */
p = ssl_handshake_start(s) + 4;
s2n(len - 6, p);
s->state=SSL3_ST_SW_SESSION_TICKET_B;
OPENSSL_free(senc);
}
/* SSL3_ST_SW_SESSION_TICKET_B */
return ssl_do_write(s);
}
#if 0
int ssl3_send_cert_status(SSL *s)
{
if (s->state == SSL3_ST_SW_CERT_STATUS_A)
{
unsigned char *p;
/* Grow buffer if need be: the length calculation is as
* follows 1 (message type) + 3 (message length) +
* 1 (ocsp response type) + 3 (ocsp response length)
* + (ocsp response)
*/
if (!BUF_MEM_grow(s->init_buf, 8 + s->tlsext_ocsp_resplen))
return -1;
p=(unsigned char *)s->init_buf->data;
/* do the header */
*(p++)=SSL3_MT_CERTIFICATE_STATUS;
/* message length */
l2n3(s->tlsext_ocsp_resplen + 4, p);
/* status type */
*(p++)= s->tlsext_status_type;
/* length of OCSP response */
l2n3(s->tlsext_ocsp_resplen, p);
/* actual response */
memcpy(p, s->tlsext_ocsp_resp, s->tlsext_ocsp_resplen);
/* number of bytes to write */
s->init_num = 8 + s->tlsext_ocsp_resplen;
s->state=SSL3_ST_SW_CERT_STATUS_B;
s->init_off = 0;
}
/* SSL3_ST_SW_CERT_STATUS_B */
return(ssl3_do_write(s,SSL3_RT_HANDSHAKE));
}
#endif
/* 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((int)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)
return 0;
if (!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((int)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;
}