X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/9c81ac1957c41df87348e2b76070687b83ea2b10..c23f7b7dcf9c014cf531d75c22cc254c7ca35e55:/print-tcp.c

diff --git a/print-tcp.c b/print-tcp.c
index ce1fc9aa..241d5b0f 100644
--- a/print-tcp.c
+++ b/print-tcp.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.87 2001-06-25 21:38:50 itojun Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.89 2001-09-17 20:06:18 fenner Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -99,12 +99,12 @@ static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
 #ifndef NFS_PORT
 #define NFS_PORT	2049
 #endif
+#define MSDP_PORT	639
 
 static int tcp_cksum(register const struct ip *ip,
 		     register const struct tcphdr *tp,
 		     register int len)
 {
-	int i, tlen;
 	union phu {
 		struct phdr {
 			u_int32_t src;
@@ -115,34 +115,18 @@ static int tcp_cksum(register const struct ip *ip,
 		} ph;
 		u_int16_t pa[6];
 	} phu;
-	register const u_int16_t *sp;
-	u_int32_t sum;
-	tlen = ntohs(ip->ip_len) - ((const char *)tp-(const char*)ip);
+	const u_int16_t *sp;
 
 	/* pseudo-header.. */
-	phu.ph.len = htons(tlen);
+	phu.ph.len = htons(len);	/* XXX */
 	phu.ph.mbz = 0;
 	phu.ph.proto = IPPROTO_TCP;
 	memcpy(&phu.ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t));
 	memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t));
 
 	sp = &phu.pa[0];
-	sum = sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5];
-
-	sp = (const u_int16_t *)tp;
-
-	for (i=0; i<(tlen&~1); i+= 2)
-		sum += *sp++;
-
-	if (tlen & 1) {
-		sum += htons( (*(const u_int8_t *)sp) << 8);
-	}
-
-	while (sum > 0xffff)
-		sum = (sum & 0xffff) + (sum >> 16);
-	sum = ~sum & 0xffff;
-
-	return (sum);
+	return in_cksum((u_short *)tp, len,
+			sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5]);
 }
 
 #ifdef INET6
@@ -624,6 +608,8 @@ tcp_print(register const u_char *bp, register u_int length,
 		    (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT)) {
 			/* TCP DNS query has 2byte length at the head */
 			ns_print(bp + 2, length - 2);
+		} else if (sport == MSDP_PORT || dport == MSDP_PORT) {
+			msdp_print(bp, length);
 		}
 	}
 	return;