コード例 #1
0
ファイル: d1_srvr.c プロジェクト: 0culus/openssl
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;
					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 :-)
				 * ...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; 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 */
			if ((s->options & SSL_OP_EPHEMERAL_RSA)
#ifndef OPENSSL_NO_KRB5
				&& !(alg_k & SSL_kKRB5)
#endif /* OPENSSL_NO_KRB5 */
				)
				/* option SSL_OP_EPHEMERAL_RSA sends temporary RSA key
				 * even when forbidden by protocol specs
				 * (handshake may fail as clients are not required to
				 * be able to handle this) */
				s->s3->tmp.use_rsa_tmp=1;
			else
				s->s3->tmp.use_rsa_tmp=0;

			/* only send if a DH key exchange or
			 * RSA but we have a sign only certificate */
			if (s->s3->tmp.use_rsa_tmp
			/* 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|SSL_kDHr|SSL_kDHd))
			    || (alg_k & SSL_kECDHE)
			    || ((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:
			/* Check for second client hello (MS SGC) */
			ret = ssl3_check_client_hello(s);
			if (ret <= 0)
				goto end;
			if (ret == 2)
				{
				dtls1_stop_timer(s);
				s->state = SSL3_ST_SR_CLNT_HELLO_C;
				}
			else {
				/* could be sent for a DH cert, even if we
				 * have not asked for it :-) */
				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);
					return -1;
					}
				s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
				if (!ssl3_digest_cached_records(s))
					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:

			s->d1->change_cipher_spec_ok = 1;
			/* we should decide if we expected this one */
			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:
			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; 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;
				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; */

		default:
			SSLerr(SSL_F_DTLS1_ACCEPT,SSL_R_UNKNOWN_STATE);
			ret= -1;
			goto end;
			/* break; */
			}
コード例 #2
0
ファイル: d1_srvr.c プロジェクト: project-zerus/boringssl
int dtls1_accept(SSL *s) {
  BUF_MEM *buf = NULL;
  void (*cb)(const SSL *ssl, int type, int val) = NULL;
  uint32_t alg_a;
  int ret = -1;
  int new_state, state, skip = 0;

  assert(s->handshake_func == dtls1_accept);
  assert(s->server);
  assert(SSL_IS_DTLS(s));

  ERR_clear_error();
  ERR_clear_system_error();

  if (s->info_callback != NULL) {
    cb = s->info_callback;
  } else if (s->ctx->info_callback != NULL) {
    cb = s->ctx->info_callback;
  }

  s->in_handshake++;

  if (s->cert == NULL) {
    OPENSSL_PUT_ERROR(SSL, dtls1_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_ACCEPT:
      case SSL_ST_BEFORE | SSL_ST_ACCEPT:
        if (cb != NULL) {
          cb(s, SSL_CB_HANDSHAKE_START, 1);
        }

        if (s->init_buf == NULL) {
          buf = BUF_MEM_new();
          if (buf == NULL || !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;
        }

        s->init_num = 0;

        if (s->state != SSL_ST_RENEGOTIATE) {
          if (!ssl_init_wbio_buffer(s, 1)) {
            ret = -1;
            goto end;
          }

          if (!ssl3_init_finished_mac(s)) {
            OPENSSL_PUT_ERROR(SSL, dtls1_accept, ERR_R_INTERNAL_ERROR);
            ret = -1;
            goto end;
          }

          s->state = SSL3_ST_SR_CLNT_HELLO_A;
        } else {
          /* s->state == SSL_ST_RENEGOTIATE, * we will just send a
           * HelloRequest */
          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;

        if (!ssl3_init_finished_mac(s)) {
          OPENSSL_PUT_ERROR(SSL, dtls1_accept, ERR_R_INTERNAL_ERROR);
          ret = -1;
          goto end;
        }
        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 <= 0) {
          goto end;
        }
        dtls1_stop_timer(s);
        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:
        s->renegotiate = 2;
        dtls1_start_timer(s);
        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)) {
          dtls1_start_timer(s);
          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 s3_srvr.c. Fix this. In the meantime, keep them
         * in sync. */
        if (ssl_cipher_requires_server_key_exchange(s->s3->tmp.new_cipher) ||
            ((alg_a & SSL_aPSK) && s->psk_identity_hint)) {
          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)) ||
            /* 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;
        } else {
          s->s3->tmp.cert_request = 1;
          dtls1_start_timer(s);
          ret = ssl3_send_certificate_request(s);
          if (ret <= 0) {
            goto end;
          }
          s->state = SSL3_ST_SW_SRVR_DONE_A;
          s->init_num = 0;
        }
        break;

      case SSL3_ST_SW_SRVR_DONE_A:
      case SSL3_ST_SW_SRVR_DONE_B:
        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) {
          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_FINISHED_A;
        s->init_num = 0;
        break;

      case SSL3_ST_SR_FINISHED_A:
      case SSL3_ST_SR_FINISHED_B:
        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;
        } else if (s->tlsext_ticket_expected) {
          s->state = SSL3_ST_SW_SESSION_TICKET_A;
        } else {
          s->state = SSL3_ST_SW_CHANGE_A;
        }
        s->init_num = 0;
        break;

      case SSL3_ST_SW_SESSION_TICKET_A:
      case SSL3_ST_SW_SESSION_TICKET_B:
        ret = ssl3_send_new_session_ticket(s);
        if (ret <= 0) {
          goto end;
        }
        s->state = SSL3_ST_SW_CHANGE_A;
        s->init_num = 0;
        break;

      case SSL3_ST_SW_CHANGE_A:
      case SSL3_ST_SW_CHANGE_B:
        s->session->cipher = s->s3->tmp.new_cipher;
        if (!s->enc_method->setup_key_block(s)) {
          ret = -1;
          goto end;
        }

        ret = dtls1_send_change_cipher_spec(s, SSL3_ST_SW_CHANGE_A,
                                            SSL3_ST_SW_CHANGE_B);

        if (ret <= 0) {
          goto end;
        }

        s->state = SSL3_ST_SW_FINISHED_A;
        s->init_num = 0;

        if (!s->enc_method->change_cipher_state(
                s, SSL3_CHANGE_CIPHER_SERVER_WRITE)) {
          ret = -1;
          goto end;
        }

        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->enc_method->server_finished_label,
                               s->enc_method->server_finished_label_len);
        if (ret <= 0) {
          goto end;
        }
        s->state = SSL3_ST_SW_FLUSH;
        if (s->hit) {
          s->s3->tmp.next_state = SSL3_ST_SR_FINISHED_A;
        } else {
          s->s3->tmp.next_state = SSL_ST_OK;
        }
        s->init_num = 0;
        break;

      case SSL_ST_OK:
        ssl3_cleanup_key_block(s);

        /* 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);

          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;

      default:
        OPENSSL_PUT_ERROR(SSL, dtls1_accept, SSL_R_UNKNOWN_STATE);
        ret = -1;
        goto end;
    }

    if (!s->s3->tmp.reuse_message && !skip) {
      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:
  s->in_handshake--;
  BUF_MEM_free(buf);
  if (cb != NULL) {
    cb(s, SSL_CB_ACCEPT_EXIT, ret);
  }
  return ret;
}
int dtls1_accept(SSL *s)
	{
	BUF_MEM *buf;
	void (*cb)(const SSL *ssl,int type,int val)=NULL;
	unsigned long alg_a;
	int ret= -1;
	int new_state,state,skip=0;
	int listen;

	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;
	
	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;

	if (s->cert == NULL)
		{
		OPENSSL_PUT_ERROR(SSL, dtls1_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 & 0xff00) != (DTLS1_VERSION & 0xff00))
				{
				OPENSSL_PUT_ERROR(SSL, 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;
					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 :-)
				 * ...but not with SCTP :-)
				 */
					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
				{
				/* 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:
		case SSL3_ST_SR_CLNT_HELLO_D:

			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 */
			ssl3_init_finished_mac(s);
			break;
			

		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)
				{
				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:
			/* 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;
				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;
				}
			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 s3_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))
				{
				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)) ||
				/* 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;
				}
			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;
#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:
			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;
			s->state=SSL3_ST_SR_CERT_VRFY_A;
			s->init_num=0;

			/* TODO(davidben): These two blocks are different
			 * between SSL and DTLS. Resolve the difference and code
			 * duplication. */
			if (SSL_USE_SIGALGS(s))
				{
				if (!s->session->peer)
					break;
				/* For sigalgs freeze the handshake buffer
				 * at this point and digest cached records.
				 */
				if (!s->s3->handshake_buffer)
					{
					OPENSSL_PUT_ERROR(SSL, dtls1_accept, ERR_R_INTERNAL_ERROR);
					return -1;
					}
				s->s3->flags |= TLS1_FLAGS_KEEP_HANDSHAKE;
				if (!ssl3_digest_cached_records(s))
					return -1;
				}
			else
				{
				/* 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:

			s->d1->change_cipher_spec_ok = 1;
			/* we should decide if we expected this one */
			ret=ssl3_get_cert_verify(s);
			if (ret <= 0) goto end;
				s->state=SSL3_ST_SR_FINISHED_A;
			s->init_num=0;
			break;

		case SSL3_ST_SR_FINISHED_A:
		case SSL3_ST_SR_FINISHED_B:
			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;
			else if (s->tlsext_ticket_expected)
				s->state=SSL3_ST_SW_SESSION_TICKET_A;
			else
				s->state=SSL3_ST_SW_CHANGE_A;
			s->init_num=0;
			break;

		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;


		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=dtls1_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;
				}

			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;
				}
			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);

#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; */

		default:
			OPENSSL_PUT_ERROR(SSL, 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--;

	if (cb != NULL)
		cb(s,SSL_CB_ACCEPT_EXIT,ret);
	return(ret);
	}
コード例 #4
0
ファイル: d1_srvr.c プロジェクト: vigortls/vigortls
int dtls1_accept(SSL *s)
{
    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;

    ERR_clear_error();
    errno = 0;

    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;

    if (s->cert == NULL) {
        SSLerr(SSL_F_DTLS1_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 & 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) {
                    BUF_MEM *buf;
                    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 :-)
                     */
                    if (!ssl_init_wbio_buffer(s, 1)) {
                        ret = -1;
                        s->state = SSL_ST_ERR;
                        goto end;
                    }

                    tls1_init_finished_mac(s);
                    s->state = SSL3_ST_SR_CLNT_HELLO_A;
                    s->ctx->stats.sess_accept++;
                } else if (!s->s3->send_connection_binding) {
                    /*
                     * Server attempting to renegotiate with client that doesn't
                     * support secure renegotiation.
                     */
                    SSLerr(SSL_F_DTLS1_ACCEPT,
                           SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
                    ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
                    ret = -1;
                    s->state = SSL_ST_ERR;
                    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;
                dtls1_clear_sent_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;

                tls1_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 */
                tls1_init_finished_mac(s);
                break;


            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) {
                    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:
                /* Check if it is anon DH. */
                if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL)) {
                    dtls1_start_timer(s);
                    ret = ssl3_send_server_certificate(s);
                    if (ret <= 0)
                        goto end;
                    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;
                }
                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;

                /* only send if a DH key exchange */
                if (alg_k & (SSL_kDHE | SSL_kECDHE)) {
                    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:
                /*
                 * Determine whether or not we need to request a
                 * certificate.
                 *
                 * Do not request a certificate if:
                 *
                 * - We did not ask for it (SSL_VERIFY_PEER is unset).
                 *
                 * - SSL_VERIFY_CLIENT_ONCE is set and we are
                 *   renegotiating.
                 *
                 * - We are using an anonymous ciphersuites
                 *   (see section "Certificate request" in SSL 3 drafts
                 *   and in RFC 2246) ... except when the application
                 *   insists on verification (against the specs, but
                 *   s3_clnt.c accepts this for SSL 3).
                 */
                if (!(s->verify_mode & SSL_VERIFY_PEER) ||
                    ((s->session->peer != NULL) &&
                    (s->verify_mode & SSL_VERIFY_CLIENT_ONCE)) ||
                    ((s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
                    !(s->verify_mode & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)))
                {
                    /* no cert request */
                    skip = 1;
                    s->s3->tmp.cert_request = 0;
                    s->state = SSL3_ST_SW_SRVR_DONE_A;
                } else {
                    s->s3->tmp.cert_request = 1;
                    dtls1_start_timer(s);
                    ret = ssl3_send_certificate_request(s);
                    if (ret <= 0)
                        goto end;
                    s->state = SSL3_ST_SW_SRVR_DONE_A;
                    s->init_num = 0;
                }
                break;

            case SSL3_ST_SW_SRVR_DONE_A:
            case SSL3_ST_SW_SRVR_DONE_B:
                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;

                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 (!tls1_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;
                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;
                else if (s->tlsext_ticket_expected)
                    s->state = SSL3_ST_SW_SESSION_TICKET_A;
                else
                    s->state = SSL3_ST_SW_CHANGE_A;
                s->init_num = 0;
                break;

            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;

            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;


                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;

                } 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);

                /* 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;
                dtls1_clear_received_buffer(s);
                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--;

    if (cb != NULL)
        cb(s, SSL_CB_ACCEPT_EXIT, ret);
    return ret;
}