Code: int ssl3_connect(SSL *s)
	{
	BUF_MEM *buf=NULL;
	unsigned long Time=(unsigned long)time(NULL);
	void (*cb)(const SSL *ssl,int type,int val)=NULL;
	int ret= -1;
	int new_state,state,skip=0;

	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;
	
	s->in_handshake++;
	if (!SSL_in_init(s) || SSL_in_before(s)) SSL_clear(s); 

#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)
		{
		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_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 ) != 0x0300)
				{
				SSLerr(SSL_F_SSL3_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 */

			ssl3_init_finished_mac(s);

			s->state=SSL3_ST_CW_CLNT_HELLO_A;
			s->ctx->stats.sess_connect++;
			s->init_num=0;
			break;

		case SSL3_ST_CW_CLNT_HELLO_A:
		case SSL3_ST_CW_CLNT_HELLO_B:

			s->shutdown=0;
			ret=ssl3_client_hello(s);
			if (ret <= 0) goto end;
			s->state=SSL3_ST_CR_SRVR_HELLO_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 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;
#ifndef OPENSSL_NO_TLSEXT
				if (s->tlsext_ticket_expected)
					{
					/* receive renewed session ticket */
					s->state=SSL3_ST_CR_SESSION_TICKET_A;
					}
#endif
				}
			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:
#ifndef OPENSSL_NO_TLSEXT
			ret=ssl3_check_finished(s);
			if (ret <= 0) goto end;
			if (ret == 2)
				{
				s->hit = 1;
				if (s->tlsext_ticket_expected)
					s->state=SSL3_ST_CR_SESSION_TICKET_A;
				else
					s->state=SSL3_ST_CR_FINISHED_A;
				s->init_num=0;
				break;
				}
#endif
			/* Check if it is anon DH/ECDH */
			/* or PSK */
			if (!(s->s3->tmp.new_cipher->algorithm_auth & SSL_aNULL) &&
			    !(s->s3->tmp.new_cipher->algorithm_mkey & SSL_kPSK))
				{
				ret=ssl3_get_server_certificate(s);
				if (ret <= 0) goto end;
#ifndef OPENSSL_NO_TLSEXT
				if (s->tlsext_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;
				}
#else
				}
			else
				skip=1;

			s->state=SSL3_ST_CR_KEY_EXCH_A;
#endif
			s->init_num=0;
			break;

		case SSL3_ST_CR_KEY_EXCH_A:
		case SSL3_ST_CR_KEY_EXCH_B:
			ret=ssl3_get_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;
#ifndef OPENSSL_NO_SRP
			if (s->s3->tmp.new_cipher->algorithm_mkey & SSL_kSRP)
				{
				if ((ret = SRP_Calc_A_param(s))<=0)
					{
					SSLerr(SSL_F_SSL3_CONNECT,SSL_R_SRP_A_CALC);
					ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_INTERNAL_ERROR);
					goto end;
					}
				}
#endif
			if (s->s3->tmp.cert_req)
				s->state=SSL3_ST_CW_CERT_A;
			else
				s->state=SSL3_ST_CW_KEY_EXCH_A;
			s->init_num=0;

			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:
			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:
			ret=ssl3_send_client_key_exchange(s);
			if (ret <= 0) goto end;
			/* EAY EAY EAY need to check for DH fix cert
			 * sent back */
			/* For TLS, cert_req is set to 2, so a cert chain
			 * of nothing is sent, but no verify packet is sent */
			/* XXX: For now, we do not support client 
			 * authentication in ECDH cipher suites with
			 * ECDH (rather than ECDSA) certificates.
			 * We need to skip the certificate verify 
			 * message when client's ECDH public key is sent 
			 * inside the client certificate.
			 */
			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;
				}
			if (s->s3->flags & TLS1_FLAGS_SKIP_CERT_VERIFY)
				{
				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:
			ret=ssl3_send_client_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:
			ret=ssl3_send_change_cipher_spec(s,
				SSL3_ST_CW_CHANGE_A,SSL3_ST_CW_CHANGE_B);
			if (ret <= 0) goto end;

#if defined(OPENSSL_NO_TLSEXT) || defined(OPENSSL_NO_NEXTPROTONEG)
			s->state=SSL3_ST_CW_FINISHED_A;
#else
			if (s->s3->next_proto_neg_seen)
				s->state=SSL3_ST_CW_NEXT_PROTO_A;
			else
				s->state=SSL3_ST_CW_FINISHED_A;
#endif
			s->init_num=0;

			s->session->cipher=s->s3->tmp.new_cipher;
#ifdef OPENSSL_NO_COMP
			s->session->compress_meth=0;
#else
			if (s->s3->tmp.new_compression == NULL)
				s->session->compress_meth=0;
			else
				s->session->compress_meth=
					s->s3->tmp.new_compression->id;
#endif
			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;
				}

			break;

#if !defined(OPENSSL_NO_TLSEXT) && !defined(OPENSSL_NO_NEXTPROTONEG)
		case SSL3_ST_CW_NEXT_PROTO_A:
		case SSL3_ST_CW_NEXT_PROTO_B:
			ret=ssl3_send_next_proto(s);
			if (ret <= 0) goto end;
			s->state=SSL3_ST_CW_FINISHED_A;
			break;
#endif

		case SSL3_ST_CW_FINISHED_A:
		case SSL3_ST_CW_FINISHED_B:
			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;

			/* clear flags */
			s->s3->flags&= ~SSL3_FLAGS_POP_BUFFER;
			if (s->hit)
				{
				s->s3->tmp.next_state=SSL_ST_OK;
				if (s->s3->flags & SSL3_FLAGS_DELAY_CLIENT_FINISHED)
					{
					s->state=SSL_ST_OK;
					s->s3->flags|=SSL3_FLAGS_POP_BUFFER;
					s->s3->delay_buf_pop_ret=0;
					}
				}
			else
				{
#ifndef OPENSSL_NO_TLSEXT
				/* Allow NewSessionTicket if ticket expected */
				if (s->tlsext_ticket_expected)
					s->s3->tmp.next_state=SSL3_ST_CR_SESSION_TICKET_A;
				else
#endif
				
				s->s3->tmp.next_state=SSL3_ST_CR_FINISHED_A;
				}
			s->init_num=0;
			break;

#ifndef OPENSSL_NO_TLSEXT
		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;
#endif

                case SSL3_ST_CR_FINISHED_A:
                case SSL3_ST_CR_FINISHED_B:
 
                        ret=ssl3_get_finished(s,SSL3_ST_CR_FINISHED_A,
                                SSL3_ST_CR_FINISHED_B);
                        if (ret <= 0) goto end;
			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)
				{
				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 (s->init_buf != NULL)
				{
				BUF_MEM_free(s->init_buf);
				s->init_buf=NULL;
				}

			/* If we are not 'joining' the last two packets,
			 * remove the buffering now */
			if (!(s->s3->flags & SSL3_FLAGS_POP_BUFFER))
				ssl_free_wbio_buffer(s);
			/* else do it later in ssl3_write */

			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=ssl3_connect;
			s->ctx->stats.sess_connect_good++;

			if (cb != NULL) cb(s,SSL_CB_HANDSHAKE_DONE,1);

			goto end;
			/* break; */
			
		default:
			SSLerr(SSL_F_SSL3_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;
		}

Vulnerability Type: +Info
CWE ID: CWE-310
Summary: OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly restrict processing of ChangeCipherSpec messages, which allows man-in-the-middle attackers to trigger use of a zero-length master key in certain OpenSSL-to-OpenSSL communications, and consequently hijack sessions or obtain sensitive information, via a crafted TLS handshake, aka the "CCS Injection" vulnerability.
Commit Message: 