add tracefiles for infinite loop testing

[tcpdump] / print-tcp.c

diff --git a/print-tcp.c b/print-tcp.c
index c69dbcd0d6df4a8193cdd35e35a1b27ab7108669..9a965ff43646da90edde7cc050dc59e318161365 100644 (file)
--- a/print-tcp.c
+++ b/print-tcp.c
@@ -20,8 +20,8 @@
  */
 
 #ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.107 2003-11-05 06:03:01 guy Exp $ (LBL)";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.107.2.5 2004-07-28 20:11:31 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -100,7 +100,7 @@ static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
 
 static int tcp_cksum(register const struct ip *ip,
                     register const struct tcphdr *tp,
-                    register int len)
+                    register u_int len)
 {
        union phu {
                struct phdr {
@@ -115,7 +115,7 @@ static int tcp_cksum(register const struct ip *ip,
        const u_int16_t *sp;
 
        /* pseudo-header.. */
-       phu.ph.len = htons(len);        /* XXX */
+       phu.ph.len = htons((u_int16_t)len);
        phu.ph.mbz = 0;
        phu.ph.proto = IPPROTO_TCP;
        memcpy(&phu.ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t));
@@ -131,9 +131,9 @@ static int tcp_cksum(register const struct ip *ip,
 
 #ifdef INET6
 static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
-       int len)
+       u_int len)
 {
-       size_t i, tlen;
+       size_t i;
        register const u_int16_t *sp;
        u_int32_t sum;
        union {
@@ -147,14 +147,11 @@ static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
                u_int16_t pa[20];
        } phu;
 
-       tlen = EXTRACT_16BITS(&ip6->ip6_plen) + sizeof(struct ip6_hdr) -
-           ((const char *)tp - (const char*)ip6);
-
        /* pseudo-header */
        memset(&phu, 0, sizeof(phu));
        phu.ph.ph_src = ip6->ip6_src;
        phu.ph.ph_dst = ip6->ip6_dst;
-       phu.ph.ph_len = htonl(tlen);
+       phu.ph.ph_len = htonl(len);
        phu.ph.ph_nxt = IPPROTO_TCP;
 
        sum = 0;
@@ -163,10 +160,10 @@ static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
 
        sp = (const u_int16_t *)tp;
 
-       for (i = 0; i < (tlen & ~1); i += 2)
+       for (i = 0; i < (len & ~1); i += 2)
                sum += *sp++;
 
-       if (tlen & 1)
+       if (len & 1)
                sum += htons((*(const u_int8_t *)sp) << 8);
 
        while (sum > 0xffff)
@@ -215,11 +212,12 @@ tcp_print(register const u_char *bp, register u_int length,
        hlen = TH_OFF(tp) * 4;
 
        /*
-        * If data present and NFS port used, assume NFS.
+        * If data present, header length valid, and NFS port used,
+        * assume NFS.
         * Pass offset of data plus 4 bytes for RPC TCP msg length
         * to NFS print routines.
         */
-       if (!qflag) {
+       if (!qflag && hlen >= sizeof(*tp) && hlen <= length) {
                if ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend &&
                    dport == NFS_PORT) {
                        nfsreq_print((u_char *)tp + hlen + 4, length - hlen,
@@ -260,6 +258,12 @@ tcp_print(register const u_char *bp, register u_int length,
                }
        }
 
+       if (hlen < sizeof(*tp)) {
+               (void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
+                   length - hlen, hlen, (unsigned long)sizeof(*tp));
+               return;
+       }
+
        TCHECK(*tp);
 
        seq = EXTRACT_32BITS(&tp->th_seq);
@@ -268,7 +272,11 @@ tcp_print(register const u_char *bp, register u_int length,
        urp = EXTRACT_16BITS(&tp->th_urp);
 
        if (qflag) {
-               (void)printf("tcp %d", length - TH_OFF(tp) * 4);
+               (void)printf("tcp %d", length - hlen);
+               if (hlen > length) {
+                       (void)printf(" [bad hdr length %u - too long, > %u]",
+                           hlen, length);
+               }
                return;
        }
        if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH|
@@ -394,7 +402,8 @@ tcp_print(register const u_char *bp, register u_int length,
                thseq = thack = threv = 0;
        }
        if (hlen > length) {
-               (void)printf(" [bad hdr length]");
+               (void)printf(" [bad hdr length %u - too long, > %u]",
+                   hlen, length);
                return;
        }