]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-tcp.c
add tracefiles for infinite loop testing
[tcpdump] / print-tcp.c
index f841a63714f4dea05e9d79cdd0c6b191e5d5a898..9a965ff43646da90edde7cc050dc59e318161365 100644 (file)
  */
 
 #ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.55 1999-10-07 23:47:12 mcr 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
 
-#include <sys/param.h>
-#include <sys/time.h>
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
 
-#include <netinet/in.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/ip_var.h>
-#include <netinet/tcp.h>
-#include <netinet/tcpip.h>
+#include <tcpdump-stdinc.h>
+
+#include <rpc/rpc.h>
 
-#ifdef HAVE_MEMORY_H
-#include <memory.h>
-#endif
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
 #include "interface.h"
 #include "addrtoname.h"
 #include "extract.h"
 
-/* Compatibility */
-#ifndef TCPOPT_WSCALE
-#define        TCPOPT_WSCALE           3       /* window scale factor (rfc1072) */
-#endif
-#ifndef TCPOPT_SACKOK
-#define        TCPOPT_SACKOK           4       /* selective ack ok (rfc1072) */
-#endif
-#ifndef TCPOPT_SACK
-#define        TCPOPT_SACK             5       /* selective ack (rfc1072) */
-#endif
-#ifndef TCPOPT_ECHO
-#define        TCPOPT_ECHO             6       /* echo (rfc1072) */
-#endif
-#ifndef TCPOPT_ECHOREPLY
-#define        TCPOPT_ECHOREPLY        7       /* echo (rfc1072) */
-#endif
-#ifndef TCPOPT_TIMESTAMP
-#define TCPOPT_TIMESTAMP       8       /* timestamps (rfc1323) */
-#endif
-#ifndef TCPOPT_CC
-#define TCPOPT_CC              11      /* T/TCP CC options (rfc1644) */
-#endif
-#ifndef TCPOPT_CCNEW
-#define TCPOPT_CCNEW           12      /* T/TCP CC options (rfc1644) */
-#endif
-#ifndef TCPOPT_CCECHO
-#define TCPOPT_CCECHO          13      /* T/TCP CC options (rfc1644) */
+#include "tcp.h"
+
+#include "ip.h"
+#ifdef INET6
+#include "ip6.h"
 #endif
+#include "ipproto.h"
+
+#include "nameser.h"
+
+static void print_tcp_rst_data(register const u_char *sp, u_int length);
+
+#define MAX_RST_DATA_LEN       30
+
 
 struct tha {
+#ifndef INET6
        struct in_addr src;
        struct in_addr dst;
+#else
+       struct in6_addr src;
+       struct in6_addr dst;
+#endif /*INET6*/
        u_int port;
 };
 
@@ -96,43 +81,206 @@ struct tcp_seq_hash {
 static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
 
 
+#ifndef TELNET_PORT
+#define TELNET_PORT    23
+#endif
+#ifndef BGP_PORT
+#define BGP_PORT       179
+#endif
+#define NETBIOS_SSN_PORT 139
+#ifndef PPTP_PORT
+#define PPTP_PORT      1723
+#endif
+#define BEEP_PORT        10288
+#ifndef NFS_PORT
+#define NFS_PORT       2049
+#endif
+#define MSDP_PORT      639
+#define LDP_PORT        646
+
+static int tcp_cksum(register const struct ip *ip,
+                    register const struct tcphdr *tp,
+                    register u_int len)
+{
+       union phu {
+               struct phdr {
+                       u_int32_t src;
+                       u_int32_t dst;
+                       u_char mbz;
+                       u_char proto;
+                       u_int16_t len;
+               } ph;
+               u_int16_t pa[6];
+       } phu;
+       const u_int16_t *sp;
+
+       /* pseudo-header.. */
+       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));
+       if (IP_HL(ip) == 5)
+               memcpy(&phu.ph.dst, &ip->ip_dst.s_addr, sizeof(u_int32_t));
+       else
+               phu.ph.dst = ip_finddst(ip);
+
+       sp = &phu.pa[0];
+       return in_cksum((u_short *)tp, len,
+                       sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5]);
+}
+
+#ifdef INET6
+static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
+       u_int len)
+{
+       size_t i;
+       register const u_int16_t *sp;
+       u_int32_t sum;
+       union {
+               struct {
+                       struct in6_addr ph_src;
+                       struct in6_addr ph_dst;
+                       u_int32_t       ph_len;
+                       u_int8_t        ph_zero[3];
+                       u_int8_t        ph_nxt;
+               } ph;
+               u_int16_t pa[20];
+       } phu;
+
+       /* 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(len);
+       phu.ph.ph_nxt = IPPROTO_TCP;
+
+       sum = 0;
+       for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++)
+               sum += phu.pa[i];
+
+       sp = (const u_int16_t *)tp;
+
+       for (i = 0; i < (len & ~1); i += 2)
+               sum += *sp++;
+
+       if (len & 1)
+               sum += htons((*(const u_int8_t *)sp) << 8);
+
+       while (sum > 0xffff)
+               sum = (sum & 0xffff) + (sum >> 16);
+       sum = ~sum & 0xffff;
+
+       return (sum);
+}
+#endif
+
 void
 tcp_print(register const u_char *bp, register u_int length,
-         register const u_char *bp2)
+         register const u_char *bp2, int fragmented)
 {
        register const struct tcphdr *tp;
        register const struct ip *ip;
        register u_char flags;
-       register int hlen;
+       register u_int hlen;
        register char ch;
-       u_short sport, dport, win, urp;
-       u_int32_t seq, ack;
+       u_int16_t sport, dport, win, urp;
+       u_int32_t seq, ack, thseq, thack;
+       int threv;
+#ifdef INET6
+       register const struct ip6_hdr *ip6;
+#endif
 
        tp = (struct tcphdr *)bp;
        ip = (struct ip *)bp2;
+#ifdef INET6
+       if (IP_V(ip) == 6)
+               ip6 = (struct ip6_hdr *)bp2;
+       else
+               ip6 = NULL;
+#endif /*INET6*/
        ch = '\0';
-       TCHECK(*tp);
-       if (length < sizeof(*tp)) {
-               (void)printf("truncated-tcp %d", length);
+       if (!TTEST(tp->th_dport)) {
+               (void)printf("%s > %s: [|tcp]",
+                       ipaddr_string(&ip->ip_src),
+                       ipaddr_string(&ip->ip_dst));
+               return;
+       }
+
+       sport = EXTRACT_16BITS(&tp->th_sport);
+       dport = EXTRACT_16BITS(&tp->th_dport);
+
+       hlen = TH_OFF(tp) * 4;
+
+       /*
+        * 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 && 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,
+                                    (u_char *)ip);
+                       return;
+               } else if ((u_char *)tp + 4 + sizeof(struct rpc_msg)
+                          <= snapend &&
+                          sport == NFS_PORT) {
+                       nfsreply_print((u_char *)tp + hlen + 4, length - hlen,
+                                      (u_char *)ip);
+                       return;
+               }
+       }
+#ifdef INET6
+       if (ip6) {
+               if (ip6->ip6_nxt == IPPROTO_TCP) {
+                       (void)printf("%s.%s > %s.%s: ",
+                               ip6addr_string(&ip6->ip6_src),
+                               tcpport_string(sport),
+                               ip6addr_string(&ip6->ip6_dst),
+                               tcpport_string(dport));
+               } else {
+                       (void)printf("%s > %s: ",
+                               tcpport_string(sport), tcpport_string(dport));
+               }
+       } else
+#endif /*INET6*/
+       {
+               if (ip->ip_p == IPPROTO_TCP) {
+                       (void)printf("%s.%s > %s.%s: ",
+                               ipaddr_string(&ip->ip_src),
+                               tcpport_string(sport),
+                               ipaddr_string(&ip->ip_dst),
+                               tcpport_string(dport));
+               } else {
+                       (void)printf("%s > %s: ",
+                               tcpport_string(sport), tcpport_string(dport));
+               }
+       }
+
+       if (hlen < sizeof(*tp)) {
+               (void)printf(" tcp %d [bad hdr length %u - too short, < %lu]",
+                   length - hlen, hlen, (unsigned long)sizeof(*tp));
                return;
        }
 
-       sport = ntohs(tp->th_sport);
-       dport = ntohs(tp->th_dport);
-       seq = ntohl(tp->th_seq);
-       ack = ntohl(tp->th_ack);
-       win = ntohs(tp->th_win);
-       urp = ntohs(tp->th_urp);
+       TCHECK(*tp);
 
-       (void)printf("%s.%s > %s.%s: ",
-               ipaddr_string(&ip->ip_src), tcpport_string(sport),
-               ipaddr_string(&ip->ip_dst), tcpport_string(dport));
+       seq = EXTRACT_32BITS(&tp->th_seq);
+       ack = EXTRACT_32BITS(&tp->th_ack);
+       win = EXTRACT_16BITS(&tp->th_win);
+       urp = EXTRACT_16BITS(&tp->th_urp);
 
        if (qflag) {
-               (void)printf("tcp %d", length - tp->th_off * 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)) {
+       if ((flags = tp->th_flags) & (TH_SYN|TH_FIN|TH_RST|TH_PUSH|
+                                     TH_ECNECHO|TH_CWR)) {
                if (flags & TH_SYN)
                        putchar('S');
                if (flags & TH_FIN)
@@ -141,11 +289,16 @@ tcp_print(register const u_char *bp, register u_int length,
                        putchar('R');
                if (flags & TH_PUSH)
                        putchar('P');
+               if (flags & TH_CWR)
+                       putchar('W');   /* congestion _W_indow reduced (ECN) */
+               if (flags & TH_ECNECHO)
+                       putchar('E');   /* ecn _E_cho sent (ECN) */
        } else
                putchar('.');
 
        if (!Sflag && (flags & TH_ACK)) {
                register struct tcp_seq_hash *th;
+               const void *src, *dst;
                register int rev;
                struct tha tha;
                /*
@@ -154,25 +307,75 @@ tcp_print(register const u_char *bp, register u_int length,
                 * collating order so there's only one entry for
                 * both directions).
                 */
-               if (sport < dport ||
-                   (sport == dport &&
-                    ip->ip_src.s_addr < ip->ip_dst.s_addr)) {
-                       tha.src = ip->ip_src, tha.dst = ip->ip_dst;
-                       tha.port = sport << 16 | dport;
-                       rev = 0;
+#ifdef INET6
+               memset(&tha, 0, sizeof(tha));
+               rev = 0;
+               if (ip6) {
+                       src = &ip6->ip6_src;
+                       dst = &ip6->ip6_dst;
+                       if (sport > dport)
+                               rev = 1;
+                       else if (sport == dport) {
+                               if (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);
+                               tha.port = dport << 16 | sport;
+                       } else {
+                               memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
+                               memcpy(&tha.src, src, sizeof ip6->ip6_src);
+                               tha.port = sport << 16 | dport;
+                       }
                } else {
-                       tha.src = ip->ip_dst, tha.dst = ip->ip_src;
-                       tha.port = dport << 16 | sport;
+                       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)
+                                       rev = 1;
+                       }
+                       if (rev) {
+                               memcpy(&tha.src, dst, sizeof ip->ip_dst);
+                               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);
+                               tha.port = sport << 16 | dport;
+                       }
+               }
+#else
+               rev = 0;
+               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)
+                               rev = 1;
                }
+               if (rev) {
+                       memcpy(&tha.src, dst, sizeof ip->ip_dst);
+                       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);
+                       tha.port = sport << 16 | dport;
+               }
+#endif
 
+               threv = rev;
                for (th = &tcp_seq_hash[tha.port % TSEQ_HASHSIZE];
                     th->nxt; th = th->nxt)
-                       if (!memcmp((char *)&tha, (char *)&th->addr,
-                                 sizeof(th->addr)))
+                       if (memcmp((char *)&tha, (char *)&th->addr,
+                                 sizeof(th->addr)) == 0)
                                break;
 
-               if (!th->nxt || flags & TH_SYN) {
+               if (!th->nxt || (flags & TH_SYN)) {
                        /* didn't find it or new conversation */
                        if (th->nxt == NULL) {
                                th->nxt = (struct tcp_seq_hash *)
@@ -191,15 +394,47 @@ tcp_print(register const u_char *bp, register u_int length,
                        else
                                seq -= th->seq, ack -= th->ack;
                }
+
+               thseq = th->seq;
+               thack = th->ack;
+       } else {
+               /*fool gcc*/
+               thseq = thack = threv = 0;
        }
-       hlen = tp->th_off * 4;
        if (hlen > length) {
-               (void)printf(" [bad hdr length]");
+               (void)printf(" [bad hdr length %u - too long, > %u]",
+                   hlen, length);
                return;
        }
+
+       if (IP_V(ip) == 4 && vflag && !fragmented) {
+               u_int16_t sum, tcp_sum;
+               if (TTEST2(tp->th_sport, length)) {
+                       sum = tcp_cksum(ip, tp, length);
+                       if (sum != 0) {
+                               tcp_sum = EXTRACT_16BITS(&tp->th_sum);
+                               (void)printf(" [bad tcp cksum %x (->%x)!]",
+                                   tcp_sum, in_cksum_shouldbe(tcp_sum, sum));
+                       } else
+                               (void)printf(" [tcp sum ok]");
+               }
+       }
+#ifdef INET6
+       if (IP_V(ip) == 6 && ip6->ip6_plen && vflag && !fragmented) {
+               int sum;
+               if (TTEST2(tp->th_sport, length)) {
+                       sum = tcp6_cksum(ip6, tp, length);
+                       if (sum != 0)
+                               (void)printf(" [bad tcp cksum %x!]", sum);
+                       else
+                               (void)printf(" [tcp sum ok]");
+               }
+       }
+#endif
+
        length -= hlen;
-       if (length > 0 || flags & (TH_SYN | TH_FIN | TH_RST))
-               (void)printf(" %u:%u(%d)", seq, seq + length, length);
+       if (vflag > 1 || length > 0 || flags & (TH_SYN | TH_FIN | TH_RST))
+               (void)printf(" %u:%u(%u)", seq, seq + length, length);
        if (flags & TH_ACK)
                (void)printf(" ack %u", ack);
 
@@ -210,10 +445,12 @@ tcp_print(register const u_char *bp, register u_int length,
        /*
         * Handle any options.
         */
-       if ((hlen -= sizeof(*tp)) > 0) {
+       if (hlen > sizeof(*tp)) {
                register const u_char *cp;
-               register int i, opt, len, datalen;
+               register u_int i, opt, datalen;
+               register u_int len;
 
+               hlen -= sizeof(*tp);
                cp = (const u_char *)tp + sizeof(*tp);
                putchar(' ');
                ch = '<';
@@ -268,15 +505,28 @@ 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:
@@ -324,7 +574,7 @@ tcp_print(register const u_char *bp, register u_int length,
                                break;
 
                        default:
-                               (void)printf("opt-%d:", opt);
+                               (void)printf("opt-%u:", opt);
                                datalen = len - 2;
                                for (i = 0; i < datalen; ++i) {
                                        LENCHECK(i);
@@ -349,6 +599,45 @@ tcp_print(register const u_char *bp, register u_int length,
                }
                putchar('>');
        }
+
+       if (length <= 0)
+               return;
+
+       /*
+        * Decode payload if necessary.
+        */
+       bp += TH_OFF(tp) * 4;
+       if (flags & TH_RST) {
+               if (vflag)
+                       print_tcp_rst_data(bp, length);
+       } else {
+               if (sport == TELNET_PORT || dport == TELNET_PORT) {
+                       if (!qflag && vflag)
+                               telnet_print(bp, length);
+               } else if (sport == BGP_PORT || dport == BGP_PORT)
+                       bgp_print(bp, length);
+               else if (sport == PPTP_PORT || dport == PPTP_PORT)
+                       pptp_print(bp);
+#ifdef TCPDUMP_DO_SMB
+               else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT)
+                       nbt_tcp_print(bp, length);
+#endif
+               else if (sport == BEEP_PORT || dport == BEEP_PORT)
+                       beep_print(bp, length);
+               else if (length > 2 &&
+                   (sport == NAMESERVER_PORT || dport == NAMESERVER_PORT ||
+                    sport == MULTICASTDNS_PORT || dport == MULTICASTDNS_PORT)) {
+                       /*
+                        * TCP DNS query has 2byte length at the head.
+                        * XXX packet could be unaligned, it can go strange
+                        */
+                       ns_print(bp + 2, length - 2, 0);
+               } else if (sport == MSDP_PORT || dport == MSDP_PORT) {
+                       msdp_print(bp, length);
+               }
+                else if (sport == LDP_PORT || dport == LDP_PORT)
+                        printf(": LDP, length: %u", length);
+       }
        return;
 bad:
        fputs("[bad opt]", stdout);
@@ -361,3 +650,38 @@ trunc:
                putchar('>');
 }
 
+/*
+ * RFC1122 says the following on data in RST segments:
+ *
+ *         4.2.2.12  RST Segment: RFC-793 Section 3.4
+ *
+ *            A TCP SHOULD allow a received RST segment to include data.
+ *
+ *            DISCUSSION
+ *                 It has been suggested that a RST segment could contain
+ *                 ASCII text that encoded and explained the cause of the
+ *                 RST.  No standard has yet been established for such
+ *                 data.
+ *
+ */
+
+static void
+print_tcp_rst_data(register const u_char *sp, u_int length)
+{
+       int c;
+
+       if (TTEST2(*sp, length))
+               printf(" [RST");
+       else
+               printf(" [!RST");
+       if (length > MAX_RST_DATA_LEN) {
+               length = MAX_RST_DATA_LEN;      /* can use -X for longer */
+               putchar('+');                   /* indicate we truncate */
+       }
+       putchar(' ');
+       while (length-- && sp <= snapend) {
+               c = *sp++;
+               safeputchar(c);
+       }
+       putchar(']');
+}