handle ECHO and re-do SACK. From [email protected]

diff --git a/print-tcp.c b/print-tcp.c
index 80335c1ddde11410697bfb8d1ae8ae10cec78160..532d7bd8b0e588fdcea2ec8b773ace7bcd86ec77 100644 (file)
--- 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 1.57 1999-10-30 05:11:21 itojun Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.58 1999-11-21 03:50:02 assar Exp $ (LBL)";
 #endif
 
 #include <sys/param.h>
@@ -114,7 +114,8 @@ tcp_print(register const u_char *bp, register u_int length,
        register int hlen;
        register char ch;
        u_short sport, dport, win, urp;
-       u_int32_t seq, ack;
+       u_int32_t seq, ack, thseq, thack;
+       int threv;
 #ifdef INET6
        register const struct ip6_hdr *ip6;
 #endif
@@ -192,6 +193,15 @@ tcp_print(register const u_char *bp, register u_int length,
        } else
                putchar('.');
 
+       if (flags&0xc0) {
+               printf(" [");
+               if (flags&0x40)
+                       printf("ECN-Echo");
+               if (flags&0x80)
+                       printf("%sCWR", (flags&0x40) ? "," : "");
+               printf("]");
+       }
+
        if (!Sflag && (flags & TH_ACK)) {
                register struct tcp_seq_hash *th;
                register int rev;
@@ -258,6 +268,7 @@ tcp_print(register const u_char *bp, register u_int length,
                }
 #endif
 
+               threv = rev;
                for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
                     th->nxt; th = th->nxt)
                        if (!memcmp((char *)&tha, (char *)&th->addr,
@@ -278,6 +289,10 @@ tcp_print(register const u_char *bp, register u_int length,
                        else
                                th->seq = seq, th->ack = ack - 1;
                } else {
+         
+                       thseq = th->seq;
+                       thack = th->ack;
+
                        if (rev)
                                seq -= th->ack, ack -= th->seq;
                        else
@@ -360,15 +375,28 @@ tcp_print(register const u_char *bp, register u_int length,
                        case TCPOPT_SACK:
                                (void)printf("sack");
                                datalen = len - 2;
-                               for (i = 0; i < datalen; i += 4) {
-                                       LENCHECK(i + 4);
-                                       /* block-size@relative-origin */
-                                       (void)printf(" %u@%u",
-                                           EXTRACT_16BITS(cp + i + 2),
-                                           EXTRACT_16BITS(cp + i));
+                               if (datalen % 8 != 0) {
+                                       (void)printf(" malformed sack ");
+                               } else {
+                                       u_int32_t s, e;
+
+                                       (void)printf(" sack %d ", datalen / 8);
+                                       for (i = 0; i < datalen; i += 8) {
+                                               LENCHECK(i + 4);
+                                               s = EXTRACT_32BITS(cp + i);
+                                               LENCHECK(i + 8);
+                                               e = EXTRACT_32BITS(cp + i + 4);
+                                               if (threv) {
+                                                       s -= thseq;
+                                                       e -= thseq;
+                                               } else {
+                                                       s -= thack;
+                                                       e -= thack;
+                                               }
+                                               (void)printf("{%u:%u}", s, e);
+                                       }
+                                       (void)printf(" ");
                                }
-                               if (datalen % 4)
-                                       (void)printf("[len %d]", len);
                                break;
 
                        case TCPOPT_ECHO: