openssl/ssl/d1_srvr.c
Matt Caswell 464774d75f Don't allow a CCS when expecting a CertificateVerify
Currently we set change_cipher_spec_ok to 1 before calling
ssl3_get_cert_verify(). This is because this message is optional and if it
is not sent then the next thing we would expect to get is the CCS. However,
although it is optional, we do actually know whether we should be receiving
one in advance. If we have received a client cert then we should expect
a CertificateVerify message. By the time we get to this point we will
already have bombed out if we didn't get a Certificate when we should have
done, so it is safe just to check whether |peer| is NULL or not. If it is
we won't get a CertificateVerify, otherwise we will. Therefore we should
change the logic so that we only attempt to get the CertificateVerify if
we are expecting one, and not allow a CCS in this scenario.

Whilst this is good practice for TLS it is even more important for DTLS.
In DTLS messages can be lost. Therefore we may be in a situation where a
CertificateVerify message does not arrive even though one was sent. In that
case the next message the server will receive will be the CCS. This could
also happen if messages get re-ordered in-flight. In DTLS if
|change_cipher_spec_ok| is not set and a CCS is received it is ignored.
However if |change_cipher_spec_ok| *is* set then a CCS arrival will
immediately move the server into the next epoch. Any messages arriving for
the previous epoch will be ignored. This means that, in this scenario, the
handshake can never complete. The client will attempt to retransmit
missing messages, but the server will ignore them because they are the wrong
epoch. The server meanwhile will still be waiting for the CertificateVerify
which is never going to arrive.

RT#2958

Reviewed-by: Emilia Käsper <emilia@openssl.org>
(cherry picked from commit a0bd649336)
2015-05-13 11:21:01 +01:00

957 lines
33 KiB
C

/* ssl/d1_srvr.c */
/*
* 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 "ssl_locl.h"
#include <openssl/buffer.h>
#include <openssl/rand.h>
#include <openssl/objects.h>
#include <openssl/evp.h>
#include <openssl/x509.h>
#include <openssl/md5.h>
#include <openssl/bn.h>
#ifndef OPENSSL_NO_DH
# include <openssl/dh.h>
#endif
static const SSL_METHOD *dtls1_get_server_method(int ver);
static int dtls1_send_hello_verify_request(SSL *s);
static const SSL_METHOD *dtls1_get_server_method(int ver)
{
if (ver == DTLS1_VERSION)
return (DTLSv1_server_method());
else if (ver == DTLS1_2_VERSION)
return (DTLSv1_2_server_method());
else
return (NULL);
}
IMPLEMENT_dtls1_meth_func(DTLS1_VERSION,
DTLSv1_server_method,
dtls1_accept,
ssl_undefined_function,
dtls1_get_server_method, DTLSv1_enc_data)
IMPLEMENT_dtls1_meth_func(DTLS1_2_VERSION,
DTLSv1_2_server_method,
dtls1_accept,
ssl_undefined_function,
dtls1_get_server_method, DTLSv1_2_enc_data)
IMPLEMENT_dtls1_meth_func(DTLS_ANY_VERSION,
DTLS_server_method,
dtls1_accept,
ssl_undefined_function,
dtls1_get_server_method, DTLSv1_2_enc_data)
int dtls1_accept(SSL *s)
{
BUF_MEM *buf;
unsigned long Time = (unsigned long)time(NULL);
void (*cb) (const SSL *ssl, int type, int val) = NULL;
unsigned long alg_k;
int ret = -1;
int new_state, state, skip = 0;
int listen;
#ifndef OPENSSL_NO_SCTP
unsigned char sctpauthkey[64];
char labelbuffer[sizeof(DTLS1_SCTP_AUTH_LABEL)];
#endif
RAND_add(&Time, sizeof(Time), 0);
ERR_clear_error();
clear_sys_error();
if (s->info_callback != NULL)
cb = s->info_callback;
else if (s->ctx->info_callback != NULL)
cb = s->ctx->info_callback;
listen = s->d1->listen;
/* init things to blank */
s->in_handshake++;
if (!SSL_in_init(s) || SSL_in_before(s))
SSL_clear(s);
s->d1->listen = listen;
#ifndef OPENSSL_NO_SCTP
/*
* Notify SCTP BIO socket to enter handshake mode and prevent stream
* identifier other than 0. Will be ignored if no SCTP is used.
*/
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
s->in_handshake, NULL);
#endif
if (s->cert == NULL) {
SSLerr(SSL_F_DTLS1_ACCEPT, SSL_R_NO_CERTIFICATE_SET);
return (-1);
}
#ifndef OPENSSL_NO_HEARTBEATS
/*
* If we're awaiting a HeartbeatResponse, pretend we already got and
* don't await it anymore, because Heartbeats don't make sense during
* handshakes anyway.
*/
if (s->tlsext_hb_pending) {
dtls1_stop_timer(s);
s->tlsext_hb_pending = 0;
s->tlsext_hb_seq++;
}
#endif
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 & 0xff00) != (DTLS1_VERSION & 0xff00)) {
SSLerr(SSL_F_DTLS1_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;
s->state = SSL_ST_ERR;
goto end;
}
if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
BUF_MEM_free(buf);
ret = -1;
s->state = SSL_ST_ERR;
goto end;
}
s->init_buf = buf;
}
if (!ssl3_setup_buffers(s)) {
ret = -1;
s->state = SSL_ST_ERR;
goto end;
}
s->init_num = 0;
s->d1->change_cipher_spec_ok = 0;
/*
* Should have been reset by ssl3_get_finished, too.
*/
s->s3->change_cipher_spec = 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 :-) ...but not with
* SCTP :-)
*/
#ifndef OPENSSL_NO_SCTP
if (!BIO_dgram_is_sctp(SSL_get_wbio(s)))
#endif
if (!ssl_init_wbio_buffer(s, 1)) {
ret = -1;
s->state = SSL_ST_ERR;
goto end;
}
ssl3_init_finished_mac(s);
s->state = SSL3_ST_SR_CLNT_HELLO_A;
s->ctx->stats.sess_accept++;
} 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;
dtls1_clear_record_buffer(s);
dtls1_start_timer(s);
ret = ssl3_send_hello_request(s);
if (ret <= 0)
goto end;
s->s3->tmp.next_state = SSL3_ST_SR_CLNT_HELLO_A;
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:
s->shutdown = 0;
ret = ssl3_get_client_hello(s);
if (ret <= 0)
goto end;
dtls1_stop_timer(s);
if (ret == 1 && (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE))
s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A;
else
s->state = SSL3_ST_SW_SRVR_HELLO_A;
s->init_num = 0;
/*
* Reflect ClientHello sequence to remain stateless while
* listening
*/
if (listen) {
memcpy(s->s3->write_sequence, s->s3->read_sequence,
sizeof(s->s3->write_sequence));
}
/* If we're just listening, stop here */
if (listen && s->state == SSL3_ST_SW_SRVR_HELLO_A) {
ret = 2;
s->d1->listen = 0;
/*
* Set expected sequence numbers to continue the handshake.
*/
s->d1->handshake_read_seq = 2;
s->d1->handshake_write_seq = 1;
s->d1->next_handshake_write_seq = 1;
goto end;
}
break;
case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A:
case DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B:
ret = dtls1_send_hello_verify_request(s);
if (ret <= 0)
goto end;
s->state = SSL3_ST_SW_FLUSH;
s->s3->tmp.next_state = SSL3_ST_SR_CLNT_HELLO_A;
/* HelloVerifyRequest resets Finished MAC */
if (s->version != DTLS1_BAD_VER)
ssl3_init_finished_mac(s);
break;
#ifndef OPENSSL_NO_SCTP
case DTLS1_SCTP_ST_SR_READ_SOCK:
if (BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) {
s->s3->in_read_app_data = 2;
s->rwstate = SSL_READING;
BIO_clear_retry_flags(SSL_get_rbio(s));
BIO_set_retry_read(SSL_get_rbio(s));
ret = -1;
goto end;
}
s->state = SSL3_ST_SR_FINISHED_A;
break;
case DTLS1_SCTP_ST_SW_WRITE_SOCK:
ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s));
if (ret < 0)
goto end;
if (ret == 0) {
if (s->d1->next_state != SSL_ST_OK) {
s->s3->in_read_app_data = 2;
s->rwstate = SSL_READING;
BIO_clear_retry_flags(SSL_get_rbio(s));
BIO_set_retry_read(SSL_get_rbio(s));
ret = -1;
goto end;
}
}
s->state = s->d1->next_state;
break;
#endif
case SSL3_ST_SW_SRVR_HELLO_A:
case SSL3_ST_SW_SRVR_HELLO_B:
s->renegotiate = 2;
dtls1_start_timer(s);
ret = ssl3_send_server_hello(s);
if (ret <= 0)
goto end;
if (s->hit) {
#ifndef OPENSSL_NO_SCTP
/*
* Add new shared key for SCTP-Auth, will be ignored if no
* SCTP used.
*/
snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
DTLS1_SCTP_AUTH_LABEL);
SSL_export_keying_material(s, sctpauthkey,
sizeof(sctpauthkey), labelbuffer,
sizeof(labelbuffer), NULL, 0, 0);
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
sizeof(sctpauthkey), sctpauthkey);
#endif
#ifndef OPENSSL_NO_TLSEXT
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_CHANGE_A;
#endif
} 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:
/* Check if it is anon DH or normal PSK */
if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)
&& !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK)) {
dtls1_start_timer(s);
ret = ssl3_send_server_certificate(s);
if (ret <= 0)
goto end;
#ifndef OPENSSL_NO_TLSEXT
if (s->tlsext_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;
}
#else
} else
skip = 1;
s->state = SSL3_ST_SW_KEY_EXCH_A;
#endif
s->init_num = 0;
break;
case SSL3_ST_SW_KEY_EXCH_A:
case SSL3_ST_SW_KEY_EXCH_B:
alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
/*
* clear this, it may get reset by
* send_server_key_exchange
*/
s->s3->tmp.use_rsa_tmp = 0;
/*
* only send if a DH key exchange or RSA but we have a sign only
* certificate
*/
if (0
/*
* PSK: send ServerKeyExchange if PSK identity hint if
* provided
*/
#ifndef OPENSSL_NO_PSK
|| ((alg_k & SSL_kPSK) && s->ctx->psk_identity_hint)
#endif
|| (alg_k & SSL_kDHE)
|| (alg_k & SSL_kEECDH)
|| ((alg_k & SSL_kRSA)
&& (s->cert->pkeys[SSL_PKEY_RSA_ENC].privatekey == NULL
|| (SSL_C_IS_EXPORT(s->s3->tmp.new_cipher)
&& EVP_PKEY_size(s->cert->pkeys
[SSL_PKEY_RSA_ENC].privatekey) *
8 > SSL_C_EXPORT_PKEYLENGTH(s->s3->tmp.new_cipher)
)
)
)
) {
dtls1_start_timer(s);
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) ||
/*
* 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)) ||
/*
* never request cert in Kerberos ciphersuites
*/
(s->s3->tmp.new_cipher->algorithm_auth & SSL_aKRB5)
/*
* 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;
#ifndef OPENSSL_NO_SCTP
if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
}
#endif
} else {
s->s3->tmp.cert_request = 1;
dtls1_start_timer(s);
ret = ssl3_send_certificate_request(s);
if (ret <= 0)
goto end;
#ifndef NETSCAPE_HANG_BUG
s->state = SSL3_ST_SW_SRVR_DONE_A;
# ifndef OPENSSL_NO_SCTP
if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
s->d1->next_state = SSL3_ST_SW_SRVR_DONE_A;
s->state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
}
# endif
#else
s->state = SSL3_ST_SW_FLUSH;
s->s3->tmp.next_state = SSL3_ST_SR_CERT_A;
# ifndef OPENSSL_NO_SCTP
if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
s->d1->next_state = s->s3->tmp.next_state;
s->s3->tmp.next_state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
}
# endif
#endif
s->init_num = 0;
}
break;
case SSL3_ST_SW_SRVR_DONE_A:
case SSL3_ST_SW_SRVR_DONE_B:
dtls1_start_timer(s);
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:
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 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;
#ifndef OPENSSL_NO_SCTP
/*
* Add new shared key for SCTP-Auth, will be ignored if no SCTP
* used.
*/
snprintf((char *)labelbuffer, sizeof(DTLS1_SCTP_AUTH_LABEL),
DTLS1_SCTP_AUTH_LABEL);
SSL_export_keying_material(s, sctpauthkey,
sizeof(sctpauthkey), labelbuffer,
sizeof(labelbuffer), NULL, 0, 0);
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_ADD_AUTH_KEY,
sizeof(sctpauthkey), sctpauthkey);
#endif
s->state = SSL3_ST_SR_CERT_VRFY_A;
s->init_num = 0;
if (ret == 2) {
/*
* For the ECDH ciphersuites when the client sends its ECDH
* pub key in a certificate, the CertificateVerify message is
* not sent.
*/
s->state = SSL3_ST_SR_FINISHED_A;
s->init_num = 0;
} else if (SSL_USE_SIGALGS(s)) {
s->state = SSL3_ST_SR_CERT_VRFY_A;
s->init_num = 0;
if (!s->session->peer)
break;
/*
* For sigalgs freeze the handshake buffer at this point and
* digest cached records.
*/
if (!s->s3->handshake_buffer) {
SSLerr(SSL_F_DTLS1_ACCEPT, ERR_R_INTERNAL_ERROR);
s->state = SSL_ST_ERR;
return -1;
}
s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
if (!ssl3_digest_cached_records(s)) {
s->state = SSL_ST_ERR;
return -1;
}
} else {
s->state = SSL3_ST_SR_CERT_VRFY_A;
s->init_num = 0;
/*
* We need to get hashes here so if there is a client cert,
* it can be verified
*/
s->method->ssl3_enc->cert_verify_mac(s,
NID_md5,
&(s->s3->
tmp.cert_verify_md
[0]));
s->method->ssl3_enc->cert_verify_mac(s, NID_sha1,
&(s->s3->
tmp.cert_verify_md
[MD5_DIGEST_LENGTH]));
}
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;
#ifndef OPENSSL_NO_SCTP
if (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
state == SSL_ST_RENEGOTIATE)
s->state = DTLS1_SCTP_ST_SR_READ_SOCK;
else
#endif
s->state = SSL3_ST_SR_FINISHED_A;
s->init_num = 0;
break;
case SSL3_ST_SR_FINISHED_A:
case SSL3_ST_SR_FINISHED_B:
/*
* Enable CCS. Receiving a CCS clears the flag, so make
* sure not to re-enable it to ban duplicates. This *should* be the
* first time we have received one - but we check anyway to be
* cautious.
* s->s3->change_cipher_spec is set when a CCS is
* processed in d1_pkt.c, and remains set until
* the client's Finished message is read.
*/
if (!s->s3->change_cipher_spec)
s->d1->change_cipher_spec_ok = 1;
ret = ssl3_get_finished(s, SSL3_ST_SR_FINISHED_A,
SSL3_ST_SR_FINISHED_B);
if (ret <= 0)
goto end;
dtls1_stop_timer(s);
if (s->hit)
s->state = SSL_ST_OK;
#ifndef OPENSSL_NO_TLSEXT
else if (s->tlsext_ticket_expected)
s->state = SSL3_ST_SW_SESSION_TICKET_A;
#endif
else
s->state = SSL3_ST_SW_CHANGE_A;
s->init_num = 0;
break;
#ifndef OPENSSL_NO_TLSEXT
case SSL3_ST_SW_SESSION_TICKET_A:
case SSL3_ST_SW_SESSION_TICKET_B:
ret = ssl3_send_newsession_ticket(s);
if (ret <= 0)
goto end;
s->state = SSL3_ST_SW_CHANGE_A;
s->init_num = 0;
break;
case SSL3_ST_SW_CERT_STATUS_A:
case SSL3_ST_SW_CERT_STATUS_B:
ret = ssl3_send_cert_status(s);
if (ret <= 0)
goto end;
s->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;
s->state = SSL_ST_ERR;
goto end;
}
ret = dtls1_send_change_cipher_spec(s,
SSL3_ST_SW_CHANGE_A,
SSL3_ST_SW_CHANGE_B);
if (ret <= 0)
goto end;
#ifndef OPENSSL_NO_SCTP
if (!s->hit) {
/*
* Change to new shared key of SCTP-Auth, will be ignored if
* no SCTP used.
*/
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
0, NULL);
}
#endif
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;
s->state = SSL_ST_ERR;
goto end;
}
dtls1_reset_seq_numbers(s, SSL3_CC_WRITE);
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_FINISHED_A;
#ifndef OPENSSL_NO_SCTP
/*
* Change to new shared key of SCTP-Auth, will be ignored if
* no SCTP used.
*/
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_NEXT_AUTH_KEY,
0, NULL);
#endif
} else {
s->s3->tmp.next_state = SSL_ST_OK;
#ifndef OPENSSL_NO_SCTP
if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
s->d1->next_state = s->s3->tmp.next_state;
s->s3->tmp.next_state = DTLS1_SCTP_ST_SW_WRITE_SOCK;
}
#endif
}
s->init_num = 0;
break;
case SSL_ST_OK:
/* clean a few things up */
ssl3_cleanup_key_block(s);
#if 0
BUF_MEM_free(s->init_buf);
s->init_buf = NULL;
#endif
/* remove buffering on output */
ssl_free_wbio_buffer(s);
s->init_num = 0;
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 = dtls1_accept;
if (cb != NULL)
cb(s, SSL_CB_HANDSHAKE_DONE, 1);
}
ret = 1;
/* done handshaking, next message is client hello */
s->d1->handshake_read_seq = 0;
/* next message is server hello */
s->d1->handshake_write_seq = 0;
s->d1->next_handshake_write_seq = 0;
goto end;
/* break; */
case SSL_ST_ERR:
default:
SSLerr(SSL_F_DTLS1_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--;
#ifndef OPENSSL_NO_SCTP
/*
* Notify SCTP BIO socket to leave handshake mode and prevent stream
* identifier other than 0. Will be ignored if no SCTP is used.
*/
BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
s->in_handshake, NULL);
#endif
if (cb != NULL)
cb(s, SSL_CB_ACCEPT_EXIT, ret);
return (ret);
}
int dtls1_send_hello_verify_request(SSL *s)
{
unsigned int msg_len;
unsigned char *msg, *buf, *p;
if (s->state == DTLS1_ST_SW_HELLO_VERIFY_REQUEST_A) {
buf = (unsigned char *)s->init_buf->data;
msg = p = &(buf[DTLS1_HM_HEADER_LENGTH]);
/* Always use DTLS 1.0 version: see RFC 6347 */
*(p++) = DTLS1_VERSION >> 8;
*(p++) = DTLS1_VERSION & 0xFF;
if (s->ctx->app_gen_cookie_cb == NULL ||
s->ctx->app_gen_cookie_cb(s, s->d1->cookie,
&(s->d1->cookie_len)) == 0) {
SSLerr(SSL_F_DTLS1_SEND_HELLO_VERIFY_REQUEST,
ERR_R_INTERNAL_ERROR);
s->state = SSL_ST_ERR;
return 0;
}
*(p++) = (unsigned char)s->d1->cookie_len;
memcpy(p, s->d1->cookie, s->d1->cookie_len);
p += s->d1->cookie_len;
msg_len = p - msg;
dtls1_set_message_header(s, buf,
DTLS1_MT_HELLO_VERIFY_REQUEST, msg_len, 0,
msg_len);
s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B;
/* number of bytes to write */
s->init_num = p - buf;
s->init_off = 0;
}
/* s->state = DTLS1_ST_SW_HELLO_VERIFY_REQUEST_B */
return (dtls1_do_write(s, SSL3_RT_HANDSHAKE));
}