Add changes in 4.2.1.

[tcpdump] / print-tcp.c

diff --git a/print-tcp.c b/print-tcp.c
index dca5108c2628ab9ef40cab618e9ae8e67e073e25..88b461576df9a2cfe8d12d74ca87f91faff141cd 100644 (file)
--- a/print-tcp.c
+++ b/print-tcp.c
@@ -129,30 +129,8 @@ static int tcp_cksum(register const struct ip *ip,
                     register const struct tcphdr *tp,
                     register u_int len)
 {
-        struct phdr {
-                u_int32_t src;
-                u_int32_t dst;
-                u_char mbz;
-                u_char proto;
-                u_int16_t len;
-        } ph;
-        struct cksum_vec vec[2];
-
-        /* pseudo-header.. */
-        ph.len = htons((u_int16_t)len);
-        ph.mbz = 0;
-        ph.proto = IPPROTO_TCP;
-        memcpy(&ph.src, &ip->ip_src.s_addr, sizeof(u_int32_t));
-        if (IP_HL(ip) == 5)
-                memcpy(&ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t));
-        else
-                ph.dst = ip_finddst(ip);
-
-        vec[0].ptr = (const u_int8_t *)(void *)&ph;
-        vec[0].len = sizeof(ph);
-        vec[1].ptr = (const u_int8_t *)tp;
-        vec[1].len = len;
-        return in_cksum(vec, 2);
+       return (nextproto4_cksum(ip, (const u_int8_t *)tp, len,
+           IPPROTO_TCP));
 }
 
 void
@@ -412,34 +390,40 @@ tcp_print(register const u_char *bp, register u_int length,
                 return;
         }
 
-        if (IP_V(ip) == 4 && vflag && !Kflag && !fragmented) {
+        if (vflag && !Kflag && !fragmented) {
+                /* Check the checksum, if possible. */
                 u_int16_t sum, tcp_sum;
-                if (TTEST2(tp->th_sport, length)) {
-                        sum = tcp_cksum(ip, tp, length);
 
-                        (void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
-                        if (sum != 0) {
+                if (IP_V(ip) == 4) {
+                        if (TTEST2(tp->th_sport, length)) {
+                                sum = tcp_cksum(ip, tp, length);
                                 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
-                                (void)printf(" (incorrect -> 0x%04x)",in_cksum_shouldbe(tcp_sum, sum));
-                        } else
-                                (void)printf(" (correct)");
+
+                                (void)printf(", cksum 0x%04x", tcp_sum);
+                                if (sum != 0)
+                                        (void)printf(" (incorrect -> 0x%04x)",
+                                            in_cksum_shouldbe(tcp_sum, sum));
+                                else
+                                        (void)printf(" (correct)");
+                        }
                 }
-        }
 #ifdef INET6
-        if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !Kflag && !fragmented) {
-                u_int16_t sum,tcp_sum;
-                if (TTEST2(tp->th_sport, length)) {
-                        sum = nextproto6_cksum(ip6, (u_short *)tp, length, IPPROTO_TCP);
-                        (void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
-                        if (sum != 0) {
+                else if (IP_V(ip) == 6 && ip6->ip6_plen) {
+                        if (TTEST2(tp->th_sport, length)) {
+                                sum = nextproto6_cksum(ip6, (const u_int8_t *)tp, length, IPPROTO_TCP);
                                 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
-                                (void)printf(" (incorrect -> 0x%04x)",in_cksum_shouldbe(tcp_sum, sum));
-                        } else
-                                (void)printf(" (correct)");
 
+                                (void)printf(", cksum 0x%04x", tcp_sum);
+                                if (sum != 0)
+                                        (void)printf(" (incorrect -> 0x%04x)",
+                                            in_cksum_shouldbe(tcp_sum, sum));
+                                else
+                                        (void)printf(" (correct)");
+
+                        }
                 }
-        }
 #endif
+        }
 
         length -= hlen;
         if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST)) {