blob: ca8e5d6f14a7af6efd66f3a818a8b47fa75b5af5 [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) 1998-2006 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com). */
#include <assert.h>
#include <stdio.h>
#include <openssl/buf.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/rand.h>
#include "ssl_locl.h"
static const SSL_METHOD *ssl23_get_server_method(int ver);
static int ssl23_get_client_hello(SSL *s);
static int ssl23_get_v2_client_hello(SSL *s);
static const SSL_METHOD *ssl23_get_server_method(int ver)
{
if (ver == SSL3_VERSION)
return(SSLv3_server_method());
else if (ver == TLS1_VERSION)
return(TLSv1_server_method());
else if (ver == TLS1_1_VERSION)
return(TLSv1_1_server_method());
else if (ver == TLS1_2_VERSION)
return(TLSv1_2_server_method());
else
return(NULL);
}
IMPLEMENT_ssl23_meth_func(SSLv23_server_method,
ssl23_accept,
ssl_undefined_function,
ssl23_get_server_method)
int ssl23_accept(SSL *s)
{
BUF_MEM *buf;
void (*cb)(const SSL *ssl,int type,int val)=NULL;
int ret= -1;
int new_state,state;
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 (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s);
for (;;)
{
state=s->state;
switch(s->state)
{
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);
/* s->version=SSL3_VERSION; */
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;
}
ssl3_init_finished_mac(s);
s->state=SSL23_ST_SR_CLNT_HELLO;
s->ctx->stats.sess_accept++;
s->init_num=0;
break;
case SSL23_ST_SR_CLNT_HELLO:
s->shutdown = 0;
ret = ssl23_get_client_hello(s);
if (ret <= 0) goto end;
break;
case SSL23_ST_SR_V2_CLNT_HELLO:
ret = ssl23_get_v2_client_hello(s);
if (ret <= 0) goto end;
break;
case SSL23_ST_SR_SWITCH_VERSION:
if (!ssl_init_wbio_buffer(s, 1))
{
ret = -1;
goto end;
}
s->state = SSL3_ST_SR_CLNT_HELLO_A;
s->method = ssl23_get_server_method(s->version);
assert(s->method != NULL);
s->handshake_func = s->method->ssl_accept;
s->init_num = 0;
/* NULL the callback; SSL_accept will call it instead. */
cb = NULL;
ret = SSL_accept(s);
goto end;
/* break; */
default:
OPENSSL_PUT_ERROR(SSL, ssl23_accept, SSL_R_UNKNOWN_STATE);
ret= -1;
goto end;
/* break; */
}
if ((cb != NULL) && (s->state != state))
{
new_state=s->state;
s->state=state;
cb(s,SSL_CB_ACCEPT_LOOP,1);
s->state=new_state;
}
}
end:
s->in_handshake--;
if (cb != NULL)
cb(s,SSL_CB_ACCEPT_EXIT,ret);
return(ret);
}
/* ssl23_get_mutual_version determines the highest supported version for a
* client which reports a highest version of |client_version|. On success, it
* returns 1 and sets |*out_version| to the negotiated version. Otherwise, it
* returns 0. */
static int ssl23_get_mutual_version(SSL *s, int *out_version, uint16_t client_version)
{
if (client_version >= TLS1_2_VERSION && !(s->options & SSL_OP_NO_TLSv1_2))
{
*out_version = TLS1_2_VERSION;
return 1;
}
if (client_version >= TLS1_1_VERSION && !(s->options & SSL_OP_NO_TLSv1_1))
{
*out_version = TLS1_1_VERSION;
return 1;
}
if (client_version >= TLS1_VERSION && !(s->options & SSL_OP_NO_TLSv1))
{
*out_version = TLS1_VERSION;
return 1;
}
if (client_version >= SSL3_VERSION && !(s->options & SSL_OP_NO_SSLv3))
{
*out_version = SSL3_VERSION;
return 1;
}
return 0;
}
static int ssl23_get_client_hello(SSL *s)
{
uint8_t *p;
int n = 0;
/* Sniff enough of the input to determine ClientHello type and the
* client version. */
if (!ssl3_setup_buffers(s)) goto err;
/* Read the initial 11 bytes of the input. This is sufficient to
* determine the client version for a ClientHello or a
* V2ClientHello.
*
* ClientHello (assuming client_version is unfragmented):
* Byte Content
* 0 type \
* 1-2 version > record header
* 3-4 length /
* 5 msg_type \
* 6-8 length > Client Hello message
* 9-10 client_version /
*
* V2ClientHello:
* Byte Content
* 0-1 msg_length
* 2 msg_type
* 3-4 version
* 5-6 cipher_spec_length
* 7-8 session_id_length
* 9-10 challenge_length
*/
n = ssl23_read_bytes(s, 11);
if (n <= 0)
return n;
assert(n == 11);
p = s->packet;
/* 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 ", (char *)p, 4) == 0) ||
(strncmp("POST ",(char *)p, 5) == 0) ||
(strncmp("HEAD ",(char *)p, 5) == 0) ||
(strncmp("PUT ", (char *)p, 4) == 0))
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_HTTP_REQUEST);
goto err;
}
if (strncmp("CONNECT",(char *)p, 7) == 0)
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_HTTPS_PROXY_REQUEST);
goto err;
}
/* Determine if this is a ClientHello or V2ClientHello. */
if ((p[0] & 0x80) && (p[2] == SSL2_MT_CLIENT_HELLO))
{
/* This is a V2ClientHello. Determine the version to
* use. */
uint16_t client_version = (p[3] << 8) | p[4];
if (!ssl23_get_mutual_version(s, &s->version, client_version))
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_UNSUPPORTED_PROTOCOL);
goto err;
}
/* Parse the entire V2ClientHello. */
s->state = SSL23_ST_SR_V2_CLNT_HELLO;
}
else if ((p[0] == SSL3_RT_HANDSHAKE) &&
(p[1] >= SSL3_VERSION_MAJOR) &&
(p[5] == SSL3_MT_CLIENT_HELLO))
{
/* This is a fragment of a ClientHello. We look at the
* client_hello to negotiate the version. However, this
* is difficult if we have only a pathologically small
* fragment. No known client fragments ClientHello like
* this, so we simply reject such connections to avoid
* protocol version downgrade attacks. */
uint16_t record_length = (p[3] << 8) | p[4];
uint16_t client_version;
if (record_length < 6)
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_RECORD_TOO_SMALL);
goto err;
}
client_version = (p[9] << 8) | p[10];
if (!ssl23_get_mutual_version(s, &s->version, client_version))
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_client_hello, SSL_R_UNSUPPORTED_PROTOCOL);
goto err;
}
/* Reset the record-layer state for SSL3. */
assert(s->rstate == SSL_ST_READ_HEADER);
s->s3->rbuf.left = s->packet_length;
s->s3->rbuf.offset = 0;
s->packet_length = 0;
/* Ready to switch versions. */
s->state = SSL23_ST_SR_SWITCH_VERSION;
}
return 1;
err:
return -1;
}
static int ssl23_get_v2_client_hello(SSL *s)
{
uint8_t *p;
size_t i;
int n = 0;
CBS v2_client_hello, cipher_specs, session_id, challenge;
size_t msg_length, 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 11
* bytes in ssl23_get_client_hello. */
p = s->packet;
msg_length = ((p[0] & 0x7f) << 8) | p[1];
if (msg_length > (1024 * 4))
{
OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_RECORD_TOO_LARGE);
goto err;
}
if (msg_length < 11 - 2)
{
/* Reject lengths that are too short early. We have already read
* 11 bytes, so we should not attempt to process an (invalid)
* V2ClientHello which would be shorter than that. */
OPENSSL_PUT_ERROR(SSL, ssl23_get_v2_client_hello, SSL_R_RECORD_LENGTH_MISMATCH);
goto err;
}
n = ssl23_read_bytes(s, msg_length + 2);
if (n <= 0)
return n;
assert(n == s->packet_length);
/* The V2ClientHello without the length is incorporated into the
* Finished hash. */
ssl3_finish_mac(s, s->packet + 2, s->packet_length - 2);
if (s->msg_callback)
s->msg_callback(0, SSL2_VERSION, 0, s->packet+2, s->packet_length-2, s, s->msg_callback_arg); /* CLIENT-HELLO */
CBS_init(&v2_client_hello, s->packet + 2, s->packet_length - 2);
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, ssl23_get_v2_client_hello, SSL_R_DECODE_ERROR);
goto err;
}
/* 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);
i = (CBS_len(&challenge) > SSL3_RANDOM_SIZE) ? SSL3_RANDOM_SIZE : CBS_len(&challenge);
memcpy(random, CBS_data(&challenge), i);
/* 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, ssl23_get_v2_client_hello, ERR_R_MALLOC_FAILURE);
goto err;
}
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, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
goto err;
}
/* 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, ssl23_get_v2_client_hello, SSL_R_DECODE_ERROR);
goto err;
}
/* 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, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
goto err;
}
}
/* 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, ssl23_get_v2_client_hello, ERR_R_INTERNAL_ERROR);
goto err;
}
/* 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;
/* Reset the record layer for SSL3. */
assert(s->rstate == SSL_ST_READ_HEADER);
s->packet_length = 0;
s->s3->rbuf.left = 0;
s->s3->rbuf.offset = 0;
s->state = SSL23_ST_SR_SWITCH_VERSION;
return 1;
err:
return -1;
}