blob: dcee9f82a01c165b22aae1cfcd1c7f56271b52f1 [file] [log] [blame]
/*
* DTLS implementation written by Nagendra Modadugu
* (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
*/
/* ====================================================================
* Copyright (c) 1999-2007 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 (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.]
*/
#include <stdio.h>
#include <openssl/bn.h>
#include <openssl/buf.h>
#include <openssl/dh.h>
#include <openssl/evp.h>
#include <openssl/md5.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/rand.h>
#include "ssl_locl.h"
static const SSL_METHOD *dtls1_get_client_method(int ver);
static int dtls1_get_hello_verify(SSL *s);
static const SSL_METHOD *dtls1_get_client_method(int ver)
{
if (ver == DTLS1_VERSION)
return(DTLSv1_client_method());
else if (ver == DTLS1_2_VERSION)
return(DTLSv1_2_client_method());
else
return(NULL);
}
IMPLEMENT_dtls1_meth_func(DTLS1_VERSION,
DTLSv1_client_method,
ssl_undefined_function,
dtls1_connect,
dtls1_get_client_method,
DTLSv1_enc_data)
IMPLEMENT_dtls1_meth_func(DTLS1_2_VERSION,
DTLSv1_2_client_method,
ssl_undefined_function,
dtls1_connect,
dtls1_get_client_method,
DTLSv1_2_enc_data)
IMPLEMENT_dtls1_meth_func(DTLS_ANY_VERSION,
DTLS_client_method,
ssl_undefined_function,
dtls1_connect,
dtls1_get_client_method,
DTLSv1_2_enc_data)
int dtls1_connect(SSL *s)
{
BUF_MEM *buf=NULL;
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;
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_RENEGOTIATE:
s->renegotiate=1;
s->state=SSL_ST_CONNECT;
s->ctx->stats.sess_connect_renegotiate++;
/* break */
case SSL_ST_BEFORE:
case SSL_ST_CONNECT:
case SSL_ST_BEFORE|SSL_ST_CONNECT:
case SSL_ST_OK|SSL_ST_CONNECT:
s->server=0;
if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_START,1);
if ((s->version & 0xff00 ) != (DTLS1_VERSION & 0xff00))
{
OPENSSL_PUT_ERROR(SSL, dtls1_connect, ERR_R_INTERNAL_ERROR);
ret = -1;
goto end;
}
/* s->version=SSL3_VERSION; */
s->type=SSL_ST_CONNECT;
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;
buf=NULL;
}
if (!ssl3_setup_buffers(s)) { ret= -1; goto end; }
/* setup buffing BIO */
if (!ssl_init_wbio_buffer(s,0)) { ret= -1; goto end; }
/* don't push the buffering BIO quite yet */
s->state=SSL3_ST_CW_CLNT_HELLO_A;
s->ctx->stats.sess_connect++;
s->init_num=0;
s->d1->send_cookie = 0;
s->hit = 0;
break;
case SSL3_ST_CW_CLNT_HELLO_A:
case SSL3_ST_CW_CLNT_HELLO_B:
s->shutdown=0;
/* every DTLS ClientHello resets Finished MAC */
ssl3_init_finished_mac(s);
dtls1_start_timer(s);
ret=ssl3_send_client_hello(s);
if (ret <= 0) goto end;
if ( s->d1->send_cookie)
{
s->state=SSL3_ST_CW_FLUSH;
s->s3->tmp.next_state=SSL3_ST_CR_SRVR_HELLO_A;
}
else
s->state=DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A;
s->init_num=0;
/* turn on buffering for the next lot of output */
if (s->bbio != s->wbio)
s->wbio=BIO_push(s->bbio,s->wbio);
break;
case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A:
case DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B:
ret = dtls1_get_hello_verify(s);
if ( ret <= 0)
goto end;
if ( s->d1->send_cookie)
{
/* start again, with a cookie */
dtls1_stop_timer(s);
s->state = SSL3_ST_CW_CLNT_HELLO_A;
}
else
{
s->state = SSL3_ST_CR_SRVR_HELLO_A;
}
s->init_num = 0;
break;
case SSL3_ST_CR_SRVR_HELLO_A:
case SSL3_ST_CR_SRVR_HELLO_B:
ret=ssl3_get_server_hello(s);
if (ret <= 0) goto end;
if (s->hit)
{
s->state=SSL3_ST_CR_FINISHED_A;
if (s->tlsext_ticket_expected)
{
/* receive renewed session ticket */
s->state=SSL3_ST_CR_SESSION_TICKET_A;
}
}
else
{
s->state=SSL3_ST_CR_CERT_A;
}
s->init_num=0;
break;
case SSL3_ST_CR_CERT_A:
case SSL3_ST_CR_CERT_B:
if (ssl_cipher_has_server_public_key(s->s3->tmp.new_cipher))
{
ret=ssl3_get_server_certificate(s);
if (ret <= 0) goto end;
if (s->s3->tmp.certificate_status_expected)
s->state=SSL3_ST_CR_CERT_STATUS_A;
else
s->state=SSL3_ST_CR_KEY_EXCH_A;
}
else
{
skip = 1;
s->state=SSL3_ST_CR_KEY_EXCH_A;
}
s->init_num=0;
break;
case SSL3_ST_CR_KEY_EXCH_A:
case SSL3_ST_CR_KEY_EXCH_B:
ret=ssl3_get_server_key_exchange(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CR_CERT_REQ_A;
s->init_num=0;
/* at this point we check that we have the
* required stuff from the server */
if (!ssl3_check_cert_and_algorithm(s))
{
ret= -1;
goto end;
}
break;
case SSL3_ST_CR_CERT_REQ_A:
case SSL3_ST_CR_CERT_REQ_B:
ret=ssl3_get_certificate_request(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CR_SRVR_DONE_A;
s->init_num=0;
break;
case SSL3_ST_CR_SRVR_DONE_A:
case SSL3_ST_CR_SRVR_DONE_B:
ret=ssl3_get_server_done(s);
if (ret <= 0) goto end;
dtls1_stop_timer(s);
if (s->s3->tmp.cert_req)
s->s3->tmp.next_state=SSL3_ST_CW_CERT_A;
else
s->s3->tmp.next_state=SSL3_ST_CW_KEY_EXCH_A;
s->init_num=0;
s->state=s->s3->tmp.next_state;
break;
case SSL3_ST_CW_CERT_A:
case SSL3_ST_CW_CERT_B:
case SSL3_ST_CW_CERT_C:
case SSL3_ST_CW_CERT_D:
dtls1_start_timer(s);
ret=ssl3_send_client_certificate(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CW_KEY_EXCH_A;
s->init_num=0;
break;
case SSL3_ST_CW_KEY_EXCH_A:
case SSL3_ST_CW_KEY_EXCH_B:
dtls1_start_timer(s);
ret=ssl3_send_client_key_exchange(s);
if (ret <= 0) goto end;
/* For TLS, cert_req is set to 2, so a cert chain
* of nothing is sent, but no verify packet is sent */
if (s->s3->tmp.cert_req == 1)
{
s->state=SSL3_ST_CW_CERT_VRFY_A;
}
else
{
s->state=SSL3_ST_CW_CHANGE_A;
s->s3->change_cipher_spec=0;
}
s->init_num=0;
break;
case SSL3_ST_CW_CERT_VRFY_A:
case SSL3_ST_CW_CERT_VRFY_B:
dtls1_start_timer(s);
ret=ssl3_send_cert_verify(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CW_CHANGE_A;
s->init_num=0;
s->s3->change_cipher_spec=0;
break;
case SSL3_ST_CW_CHANGE_A:
case SSL3_ST_CW_CHANGE_B:
if (!s->hit)
dtls1_start_timer(s);
ret=dtls1_send_change_cipher_spec(s,
SSL3_ST_CW_CHANGE_A,SSL3_ST_CW_CHANGE_B);
if (ret <= 0) goto end;
s->state=SSL3_ST_CW_FINISHED_A;
s->init_num=0;
s->session->cipher=s->s3->tmp.new_cipher;
if (!s->method->ssl3_enc->setup_key_block(s))
{
ret= -1;
goto end;
}
if (!s->method->ssl3_enc->change_cipher_state(s,
SSL3_CHANGE_CIPHER_CLIENT_WRITE))
{
ret= -1;
goto end;
}
dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
break;
case SSL3_ST_CW_FINISHED_A:
case SSL3_ST_CW_FINISHED_B:
if (!s->hit)
dtls1_start_timer(s);
ret=ssl3_send_finished(s,
SSL3_ST_CW_FINISHED_A,SSL3_ST_CW_FINISHED_B,
s->method->ssl3_enc->client_finished_label,
s->method->ssl3_enc->client_finished_label_len);
if (ret <= 0) goto end;
s->state=SSL3_ST_CW_FLUSH;
if (s->hit)
{
s->s3->tmp.next_state=SSL_ST_OK;
}
else
{
/* Allow NewSessionTicket if ticket expected */
if (s->tlsext_ticket_expected)
s->s3->tmp.next_state=SSL3_ST_CR_SESSION_TICKET_A;
else
s->s3->tmp.next_state=SSL3_ST_CR_FINISHED_A;
}
s->init_num=0;
break;
case SSL3_ST_CR_SESSION_TICKET_A:
case SSL3_ST_CR_SESSION_TICKET_B:
ret=ssl3_get_new_session_ticket(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CR_FINISHED_A;
s->init_num=0;
break;
case SSL3_ST_CR_CERT_STATUS_A:
case SSL3_ST_CR_CERT_STATUS_B:
ret=ssl3_get_cert_status(s);
if (ret <= 0) goto end;
s->state=SSL3_ST_CR_KEY_EXCH_A;
s->init_num=0;
break;
case SSL3_ST_CR_FINISHED_A:
case SSL3_ST_CR_FINISHED_B:
s->d1->change_cipher_spec_ok = 1;
ret=ssl3_get_finished(s,SSL3_ST_CR_FINISHED_A,
SSL3_ST_CR_FINISHED_B);
if (ret <= 0) goto end;
dtls1_stop_timer(s);
if (s->hit)
s->state=SSL3_ST_CW_CHANGE_A;
else
s->state=SSL_ST_OK;
s->init_num=0;
break;
case SSL3_ST_CW_FLUSH:
s->rwstate=SSL_WRITING;
if (BIO_flush(s->wbio) <= 0)
{
/* If the write error was fatal, stop trying */
if (!BIO_should_retry(s->wbio))
{
s->rwstate=SSL_NOTHING;
s->state=s->s3->tmp.next_state;
}
ret= -1;
goto end;
}
s->rwstate=SSL_NOTHING;
s->state=s->s3->tmp.next_state;
break;
case SSL_ST_OK:
/* clean a few things up */
ssl3_cleanup_key_block(s);
#if 0
if (s->init_buf != NULL)
{
BUF_MEM_free(s->init_buf);
s->init_buf=NULL;
}
#endif
/* Remove write buffering now. */
ssl_free_wbio_buffer(s);
s->init_num=0;
s->renegotiate=0;
s->new_session=0;
ssl_update_cache(s,SSL_SESS_CACHE_CLIENT);
if (s->hit) s->ctx->stats.sess_hit++;
ret=1;
/* s->server=0; */
s->handshake_func=dtls1_connect;
s->ctx->stats.sess_connect_good++;
if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);
/* done with handshaking */
s->d1->handshake_read_seq = 0;
s->d1->next_handshake_write_seq = 0;
goto end;
/* break; */
default:
OPENSSL_PUT_ERROR(SSL, dtls1_connect, SSL_R_UNKNOWN_STATE);
ret= -1;
goto end;
/* break; */
}
/* did we do anything */
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_CONNECT_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_CONNECT_EXIT,ret);
return(ret);
}
static int dtls1_get_hello_verify(SSL *s)
{
long n;
int al, ok = 0;
CBS hello_verify_request, cookie;
uint16_t server_version;
s->first_packet = 1;
n=s->method->ssl_get_message(s,
DTLS1_ST_CR_HELLO_VERIFY_REQUEST_A,
DTLS1_ST_CR_HELLO_VERIFY_REQUEST_B,
-1,
/* Use the same maximum size as ssl3_get_server_hello. */
20000,
SSL_GET_MESSAGE_HASH_MESSAGE,
&ok);
s->first_packet = 0;
if (!ok) return((int)n);
if (s->s3->tmp.message_type != DTLS1_MT_HELLO_VERIFY_REQUEST)
{
s->d1->send_cookie = 0;
s->s3->tmp.reuse_message = 1;
return(1);
}
CBS_init(&hello_verify_request, s->init_msg, n);
if (!CBS_get_u16(&hello_verify_request, &server_version) ||
!CBS_get_u8_length_prefixed(&hello_verify_request, &cookie) ||
CBS_len(&hello_verify_request) != 0)
{
al = SSL_AD_DECODE_ERROR;
OPENSSL_PUT_ERROR(SSL, ssl3_get_cert_status, SSL_R_DECODE_ERROR);
goto f_err;
}
if (CBS_len(&cookie) > sizeof(s->d1->cookie))
{
al=SSL_AD_ILLEGAL_PARAMETER;
goto f_err;
}
memcpy(s->d1->cookie, CBS_data(&cookie), CBS_len(&cookie));
s->d1->cookie_len = CBS_len(&cookie);
s->d1->send_cookie = 1;
return 1;
f_err:
ssl3_send_alert(s, SSL3_AL_FATAL, al);
return -1;
}