Commit 4817504d authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

PR: 2658

Submitted by: Robin Seggelmann <seggelmann@fh-muenster.de>
Reviewed by: steve

Support for TLS/DTLS heartbeats.
parent 84b6e277
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+3 −0
Original line number Diff line number Diff line
@@ -255,6 +255,9 @@
  
 Changes between 1.0.0f and 1.0.1  [xx XXX xxxx]

  *) Add support for TLS/DTLS heartbeats.
     [Robin Seggelmann <seggelmann@fh-muenster.de>]

  *) Improved PRNG seeding for VOS.
     [Paul Green <Paul.Green@stratus.com>]

+20 −0
Original line number Diff line number Diff line
@@ -603,6 +603,26 @@ void MS_CALLBACK msg_cb(int write_p, int version, int content_type, const void *
					}
				}
			}

#ifndef OPENSSL_NO_HEARTBEATS
		if (content_type == 24) /* Heartbeat */
			{
			str_details1 = ", Heartbeat";
			
			if (len > 0)
				{
				switch (((const unsigned char*)buf)[0])
					{
				case 1:
					str_details1 = ", HeartbeatRequest";
					break;
				case 2:
					str_details1 = ", HeartbeatResponse";
					break;
					}
				}
			}
#endif
		}

	BIO_printf(bio, "%s %s%s [length %04lx]%s%s\n", str_write_p, str_version, str_content_type, (unsigned long)len, str_details1, str_details2);
+8 −0
Original line number Diff line number Diff line
@@ -1862,6 +1862,14 @@ printf("read=%d pending=%d peek=%d\n",k,SSL_pending(con),SSL_peek(con,zbuf,10240
				SSL_renegotiate(con);
				cbuf_len=0;
				}
#ifndef OPENSSL_NO_HEARTBEATS
			else if ((!c_ign_eof) && (cbuf[0] == 'B'))
 				{
				BIO_printf(bio_err,"HEARTBEATING\n");
				SSL_heartbeat(con);
				cbuf_len=0;
				}
#endif
			else
				{
				cbuf_len=i;
+10 −0
Original line number Diff line number Diff line
@@ -2222,6 +2222,16 @@ static int sv_body(char *hostname, int s, unsigned char *context)
					goto err;
					}

#ifndef OPENSSL_NO_HEARTBEATS
				if ((buf[0] == 'B') &&
					((buf[1] == '\n') || (buf[1] == '\r')))
					{
					BIO_printf(bio_err,"HEARTBEATING\n");
					SSL_heartbeat(con);
					i=0;
					continue;
					}
#endif
				if ((buf[0] == 'r') && 
					((buf[1] == '\n') || (buf[1] == '\r')))
					{
+151 −1
Original line number Diff line number Diff line
@@ -1084,7 +1084,11 @@ int dtls1_read_failed(SSL *s, int code)
		return code;
		}

#ifndef OPENSSL_NO_HEARTBEATS
	if (!SSL_in_init(s) && !s->tlsext_hb_pending)  /* done, no need to send a retransmit */
#else
	if (!SSL_in_init(s))  /* done, no need to send a retransmit */
#endif
		{
		BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ);
		return code;
@@ -1438,3 +1442,149 @@ int dtls1_shutdown(SSL *s)
#endif
	return ret;
	}

#ifndef OPENSSL_NO_HEARTBEATS
int
dtls1_process_heartbeat(SSL *s)
	{
	unsigned char *p = &s->s3->rrec.data[0], *pl;
	unsigned short hbtype;
	unsigned int payload;
	unsigned int padding = 16; /* Use minimum padding */

	/* Read type and payload length first */
	hbtype = *p++;
	n2s(p, payload);
	pl = p;

	if (s->msg_callback)
		s->msg_callback(0, s->version, TLS1_RT_HEARTBEAT,
			&s->s3->rrec.data[0], s->s3->rrec.length,
			s, s->msg_callback_arg);

	if (hbtype == TLS1_HB_REQUEST)
		{
		unsigned char *buffer, *bp;
		int r;

		/* Allocate memory for the response, size is 1 byte
		 * message type, plus 2 bytes payload length, plus
		 * payload, plus padding
		 */
		buffer = OPENSSL_malloc(1 + 2 + payload + padding);
		bp = buffer;

		/* Enter response type, length and copy payload */
		*bp++ = TLS1_HB_RESPONSE;
		s2n(payload, bp);
		memcpy(bp, pl, payload);
		/* Random padding */
		RAND_pseudo_bytes(p, padding);

		r = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buffer, 3 + payload + padding);

		if (r >= 0 && s->msg_callback)
			s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
				buffer, 3 + payload + padding,
				s, s->msg_callback_arg);

		OPENSSL_free(buffer);

		if (r < 0)
			return r;
		}
	else if (hbtype == TLS1_HB_RESPONSE)
		{
		unsigned int seq;

		/* We only send sequence numbers (2 bytes unsigned int),
		 * and 16 random bytes, so we just try to read the
		 * sequence number */
		n2s(pl, seq);

		if (payload == 18 && seq == s->tlsext_hb_seq)
			{
			dtls1_stop_timer(s);
			s->tlsext_hb_seq++;
			s->tlsext_hb_pending = 0;
			}
		}

	return 0;
	}

int
dtls1_heartbeat(SSL *s)
	{
	unsigned char *buf, *p;
	int ret;
	unsigned int payload = 18; /* Sequence number + random bytes */
	unsigned int padding = 16; /* Use minimum padding */

	/* Only send if peer supports and accepts HB requests... */
	if (!(s->tlsext_heartbeat & SSL_TLSEXT_HB_ENABLED) ||
	    s->tlsext_heartbeat & SSL_TLSEXT_HB_DONT_SEND_REQUESTS)
		{
		SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
		return -1;
		}

	/* ...and there is none in flight yet... */
	if (s->tlsext_hb_pending)
		{
		SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_TLS_HEARTBEAT_PENDING);
		return -1;
		}

	/* ...and no handshake in progress. */
	if (SSL_in_init(s) || s->in_handshake)
		{
		SSLerr(SSL_F_DTLS1_HEARTBEAT,SSL_R_UNEXPECTED_MESSAGE);
		return -1;
		}

	/* Check if padding is too long, payload and padding
	 * must not exceed 2^14 - 3 = 16381 bytes in total.
	 */
	OPENSSL_assert(payload + padding <= 16381);

	/* Create HeartBeat message, we just use a sequence number
	 * as payload to distuingish different messages and add
	 * some random stuff.
	 *  - Message Type, 1 byte
	 *  - Payload Length, 2 bytes (unsigned int)
	 *  - Payload, the sequence number (2 bytes uint)
	 *  - Payload, random bytes (16 bytes uint)
	 *  - Padding
	 */
	buf = OPENSSL_malloc(1 + 2 + payload + padding);
	p = buf;
	/* Message Type */
	*p++ = TLS1_HB_REQUEST;
	/* Payload length (18 bytes here) */
	s2n(payload, p);
	/* Sequence number */
	s2n(s->tlsext_hb_seq, p);
	/* 16 random bytes */
	RAND_pseudo_bytes(p, 16);
	p += 16;
	/* Random padding */
	RAND_pseudo_bytes(p, padding);

	ret = dtls1_write_bytes(s, TLS1_RT_HEARTBEAT, buf, 3 + payload + padding);
	if (ret >= 0)
		{
		if (s->msg_callback)
			s->msg_callback(1, s->version, TLS1_RT_HEARTBEAT,
				buf, 3 + payload + padding,
				s, s->msg_callback_arg);

		dtls1_start_timer(s);
		s->tlsext_hb_pending = 1;
		}

	OPENSSL_free(buf);

	return ret;
	}
#endif
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