From: Guus Sliepen <guus@meshlink.io>
Date: Sat, 9 Aug 2014 09:56:59 +0000 (+0200)
Subject: Fix packet length check in sptps_receive_data_datagram().
X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=4f58bbcc171f8566b190fce9b1817a0f62fb94d2;p=meshlink

Fix packet length check in sptps_receive_data_datagram().
---

diff --git a/src/sptps.c b/src/sptps.c
index 99a3cea9..49e0a336 100644
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -371,12 +371,12 @@ static bool receive_handshake(sptps_t *s, const char *data, uint16_t len) {
 
 // Check datagram for valid HMAC
 bool sptps_verify_datagram(sptps_t *s, const void *data, size_t len) {
-	if(len < 21)
-		return error(s, EIO, "Received short packet in sptps_verify_datagram");
-
 	if (!s->instate)
 		return error(s, EIO, "SPTPS state not ready to verify this datagram");
 
+	if(len < 21)
+		return error(s, EIO, "Received short packet in sptps_verify_datagram");
+
 	uint32_t seqno;
 	memcpy(&seqno, data, 4);
 	seqno = ntohl(seqno);
@@ -391,12 +391,9 @@ bool sptps_verify_datagram(sptps_t *s, const void *data, size_t len) {
 static bool sptps_receive_data_datagram(sptps_t *s, const void *vdata, size_t len) {
 	const char *data = vdata;
 
-	if(len < 21)
+	if(len < (s->instate ? 21 : 5))
 		return error(s, EIO, "Received short packet in sptps_receive_data_datagram");
 
-	if (!s->instate)
-		return error(s, EIO, "SPTPS state not ready to verify this datagram");
-
 	uint32_t seqno;
 	memcpy(&seqno, data, 4);
 	seqno = ntohl(seqno);