Fix warnings for functions marked __attribute((warn_unused_result)).

src/net_packet.c

@@ -669,7 +669,11 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	/* Add the message authentication code */
 
 	if(digest_active(n->outdigest)) {
-		digest_create(n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len);
+		if(!digest_create(n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len)) {
+			logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname);
+			goto end;
+		}
+
 		inpkt->len += digest_length(n->outdigest);
 	}
 

src/openssl/prf.c

@@ -54,10 +54,16 @@ static bool prf_xor(int nid, const char *secret, size_t secretlen, char *seed, s
 
 	while(outlen > 0) {
 		/* Inner HMAC */
-		digest_create(digest, data, len + seedlen, data);
+		if(!digest_create(digest, data, len + seedlen, data)) {
+			digest_close(digest);
+			return false;
+		}
 
 		/* Outer HMAC */
-		digest_create(digest, data, len + seedlen, hash);
+		if(!digest_create(digest, data, len + seedlen, hash)) {
+			digest_close(digest);
+			return false;
+		}
 
 		/* XOR the results of the outer HMAC into the out buffer */
 		for(int i = 0; i < len && i < outlen; i++)

src/protocol_auth.c

@@ -273,7 +273,8 @@ bool send_metakey(connection_t *c) {
 
 	key[0] &= 0x7F;
 
-	cipher_set_key_from_rsa(c->outcipher, key, len, true);
+	if(!cipher_set_key_from_rsa(c->outcipher, key, len, true))
+		return false;
 
 	if(debug_level >= DEBUG_SCARY_THINGS) {
 		bin2hex(key, hexkey, len);
@@ -403,11 +404,10 @@ bool challenge_h(connection_t *c, const char *request) {
 		return false;
 	}
 
-	c->allow_request = CHAL_REPLY;
-
 	/* Calculate the hash from the challenge we received */
 
-	digest_create(c->indigest, buffer, len, digest);
+	if(!digest_create(c->indigest, buffer, len, digest))
+		return false;
 
 	/* Convert the hash to a hexadecimal formatted string */
 
@@ -415,6 +415,8 @@ bool challenge_h(connection_t *c, const char *request) {
 
 	/* Send the reply */
 
+	c->allow_request = CHAL_REPLY;
+
 	return send_request(c, "%d %s", CHAL_REPLY, buffer);
 }
 

src/protocol_key.c

@@ -273,8 +273,10 @@ bool send_ans_key(node_t *to) {
 		abort();
 
 	randomize(key, keylen);
-	cipher_set_key(to->incipher, key, false);
-	digest_set_key(to->indigest, key, keylen);
+	if(!cipher_set_key(to->incipher, key, false))
+		abort();
+	if(!digest_set_key(to->indigest, key, keylen))
+		abort();
 
 	bin2hex(key, key, keylen);
 
@@ -418,8 +420,10 @@ bool ans_key_h(connection_t *c, const char *request) {
 
 	/* Update our copy of the origin's packet key */
 
-	cipher_set_key(from->outcipher, key, true);
-	digest_set_key(from->outdigest, key, keylen);
+	if(!cipher_set_key(from->outcipher, key, true))
+		return false;
+	if(!digest_set_key(from->outdigest, key, keylen))
+		return false;
 
 	from->status.validkey = true;
 	from->sent_seqno = 0;

src/sptps.c

@@ -98,7 +98,9 @@ static bool send_record_priv_datagram(sptps_t *s, uint8_t type, const char *data
 
 	if(s->outstate) {
 		// If first handshake has finished, encrypt and HMAC
-		cipher_set_counter(s->outcipher, &seqno, sizeof seqno);
+		if(!cipher_set_counter(s->outcipher, &seqno, sizeof seqno))
+			return false;
+
 		if(!cipher_counter_xor(s->outcipher, buffer + 6, len + 1UL, buffer + 6))
 			return false;
 
@@ -490,7 +492,8 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
 
 	// Decrypt.
 	memcpy(&seqno, buffer + 2, 4);
-	cipher_set_counter(s->incipher, &seqno, sizeof seqno);
+	if(!cipher_set_counter(s->incipher, &seqno, sizeof seqno))
+		return false;
 	if(!cipher_counter_xor(s->incipher, buffer + 6, len - 4, buffer + 6))
 		return false;