stun

commit fc6e63001ac35a01eb4854e68068582a36224175
parent 280abdc491b629e2d774c843d34aeae5eeac536b
Author: sin <sin@2f30.org>
Date:   Thu, 17 Mar 2016 23:07:10 +0000

Make payload length 2 octets instead of 4

Diffstat:
M
stun.c
 | 
18
++++++++----------

1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/stun.c b/stun.c
@@ -25,7 +25,7 @@
 
 #include "arg.h"
 
-#define HDRLEN		4
+#define HDRLEN		2
 #define MTU		1440
 
 EVP_CIPHER_CTX enc, dec;
@@ -136,18 +136,16 @@ readtun(int fd, unsigned char *buf, int len)
 }
 
 void
-packint(unsigned char *buf, int n)
+pack16(unsigned char *buf, int n)
 {
-	buf[0] = n >> 24 & 0xff;
-	buf[1] = n >> 16 & 0xff;
-	buf[2] = n >>  8 & 0xff;
-	buf[3] = n & 0xff;
+	buf[0] = n >> 8 & 0xff;
+	buf[1] = n & 0xff;
 }
 
 int
-unpackint(unsigned char *buf)
+unpack16(unsigned char *buf)
 {
-	return (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
+	return (buf[0] << 8) | buf[1];
 }
 
 /* handles partial writes */
@@ -180,7 +178,7 @@ writenet(int fd, unsigned char *buf, int len)
 	int pktlen;
 
 	pktlen = aesenc(&enc, &encbuf[HDRLEN], buf, len);
-	packint(encbuf, pktlen);
+	pack16(encbuf, pktlen);
 	pktlen += HDRLEN;
 	return writeall(fd, encbuf, pktlen);
 }
@@ -218,7 +216,7 @@ readnet(int fd, unsigned char *buf, int len)
 	n = readall(fd, hdr, sizeof(hdr));
 	if (n <= 0)
 		return n;
-	pktlen = unpackint(hdr);
+	pktlen = unpack16(hdr);
 	if (pktlen < 0 || pktlen > MTU + AES_BLOCK_SIZE) {
 		warnx("bogus payload length: %d", pktlen);
 		return -1;