fix partial checksum errors in DCCP decoder, IPv6 case

[tcpdump] / print-tcp.c

diff --git a/print-tcp.c b/print-tcp.c
index b63bc4ebf21fd53303ff74e0f5b32e2fd766bad4..e5acfa4c0694c977df85c84308a0a72ab98a4b3a 100644 (file)
--- a/print-tcp.c
+++ b/print-tcp.c
@@ -142,8 +142,8 @@ static int tcp_cksum(register const struct ip *ip,
                     register const struct tcphdr *tp,
                     register u_int len)
 {
-       return (nextproto4_cksum(ip, (const u_int8_t *)tp, len,
-           IPPROTO_TCP));
+       return nextproto4_cksum(ip, (const u_int8_t *)tp, len, len,
+                               IPPROTO_TCP);
 }
 
 void
@@ -258,16 +258,16 @@ tcp_print(register const u_char *bp, register u_int length,
                         if (sport > dport)
                                 rev = 1;
                         else if (sport == dport) {
-                                if (memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
+                                if (UNALIGNED_MEMCMP(src, dst, sizeof ip6->ip6_dst) > 0)
                                         rev = 1;
                         }
                         if (rev) {
-                                memcpy(&tha.src, dst, sizeof ip6->ip6_dst);
-                                memcpy(&tha.dst, src, sizeof ip6->ip6_src);
+                                UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip6->ip6_dst);
+                                UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip6->ip6_src);
                                 tha.port = dport << 16 | sport;
                         } else {
-                                memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
-                                memcpy(&tha.src, src, sizeof ip6->ip6_src);
+                                UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip6->ip6_dst);
+                                UNALIGNED_MEMCPY(&tha.src, src, sizeof ip6->ip6_src);
                                 tha.port = sport << 16 | dport;
                         }
 
@@ -305,31 +305,25 @@ tcp_print(register const u_char *bp, register u_int length,
 #endif /*INET6*/
                         register struct tcp_seq_hash *th;
                         struct tcp_seq_hash *tcp_seq_hash;
-                        const void *src, *dst;
+                        const struct in_addr *src, *dst;
                         struct tha tha;
 
                         tcp_seq_hash = tcp_seq_hash4;
-                       /*
-                        * We use "void *" to keep the compiler from
-                        * assuming the structures are aligned and
-                        * generating non-unaligned-safe code for
-                        * the copies.
-                        */
-                        src = (const void *)&ip->ip_src;
-                        dst = (const void *)&ip->ip_dst;
+                        src = &ip->ip_src;
+                        dst = &ip->ip_dst;
                         if (sport > dport)
                                 rev = 1;
                         else if (sport == dport) {
-                                if (memcmp(src, dst, sizeof ip->ip_dst) > 0)
+                                if (UNALIGNED_MEMCMP(src, dst, sizeof ip->ip_dst) > 0)
                                         rev = 1;
                         }
                         if (rev) {
-                                memcpy(&tha.src, dst, sizeof ip->ip_dst);
-                                memcpy(&tha.dst, src, sizeof ip->ip_src);
+                                UNALIGNED_MEMCPY(&tha.src, dst, sizeof ip->ip_dst);
+                                UNALIGNED_MEMCPY(&tha.dst, src, sizeof ip->ip_src);
                                 tha.port = dport << 16 | sport;
                         } else {
-                                memcpy(&tha.dst, dst, sizeof ip->ip_dst);
-                                memcpy(&tha.src, src, sizeof ip->ip_src);
+                                UNALIGNED_MEMCPY(&tha.dst, dst, sizeof ip->ip_dst);
+                                UNALIGNED_MEMCPY(&tha.src, src, sizeof ip->ip_src);
                                 tha.port = sport << 16 | dport;
                         }
 
@@ -392,7 +386,8 @@ tcp_print(register const u_char *bp, register u_int length,
 #ifdef INET6
                 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);
+                                sum = nextproto6_cksum(ip6, (const u_int8_t *)tp,
+                                                       length, length, IPPROTO_TCP);
                                 tcp_sum = EXTRACT_16BITS(&tp->th_sum);
 
                                 (void)printf(", cksum 0x%04x", tcp_sum);