]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-tcp.c
Backout CHANGES update - wrong branch
[tcpdump] / print-tcp.c
index eecf0b48bdf8cd2ffd7acbbbd373653eff508600..9b6c2a2ff80c5861aa68b3fbf8f747050ca2b421 100644 (file)
@@ -2,6 +2,8 @@
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
  *     The Regents of the University of California.  All rights reserved.
  *
+ * Copyright (c) 1999-2004 The tcpdump.org project
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that: (1) source code distributions
  * retain the above copyright notice and this paragraph in its entirety, (2)
  */
 
 #ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.86 2001-05-09 01:16:57 fenner Exp $ (LBL)";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-tcp.c,v 1.120.2.3 2005-10-16 06:05:46 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <sys/param.h>
-#include <sys/time.h>
-
-#include <rpc/rpc.h>
-
-#include <netinet/in.h>
+#include <tcpdump-stdinc.h>
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <ctype.h>
-#include <unistd.h>
 
 #include "interface.h"
 #include "addrtoname.h"
@@ -51,9 +46,23 @@ static const char rcsid[] =
 #ifdef INET6
 #include "ip6.h"
 #endif
+#include "ipproto.h"
+#include "rpc_auth.h"
+#include "rpc_msg.h"
 
 #include "nameser.h"
 
+#ifdef HAVE_LIBCRYPTO
+#include <openssl/md5.h>
+
+#define SIGNATURE_VALID                0
+#define SIGNATURE_INVALID      1
+#define CANT_CHECK_SIGNATURE   2
+
+static int tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
+    const u_char *data, int length, const u_char *rcvsig);
+#endif
+
 static void print_tcp_rst_data(register const u_char *sp, u_int length);
 
 #define MAX_RST_DATA_LEN       30
@@ -95,16 +104,17 @@ static struct tcp_seq_hash tcp_seq_hash[TSEQ_HASHSIZE];
 #ifndef PPTP_PORT
 #define PPTP_PORT      1723
 #endif
-#define BXXP_PORT        10288
+#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 int len)
+                    register u_int len)
 {
-       int i, tlen;
        union phu {
                struct phdr {
                        u_int32_t src;
@@ -115,41 +125,28 @@ static int tcp_cksum(register const struct ip *ip,
                } ph;
                u_int16_t pa[6];
        } phu;
-       register const u_int16_t *sp;
-       u_int32_t sum;
-       tlen = ntohs(ip->ip_len) - ((const char *)tp-(const char*)ip);
+       const u_int16_t *sp;
 
        /* pseudo-header.. */
-       phu.ph.len = htons(tlen);
+       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));
-       memcpy(&phu.ph.dst, &ip->ip_dst.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];
-       sum = sp[0]+sp[1]+sp[2]+sp[3]+sp[4]+sp[5];
-
-       sp = (const u_int16_t *)tp;
-
-       for (i=0; i<(tlen&~1); i+= 2)
-               sum += *sp++;
-
-       if (tlen & 1) {
-               sum += htons( (*(const u_int8_t *)sp) << 8);
-       }
-
-       while (sum > 0xffff)
-               sum = (sum & 0xffff) + (sum >> 16);
-       sum = ~sum & 0xffff;
-
-       return (sum);
+       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,
-       int len)
+       u_int len)
 {
-       int i, tlen;
+       size_t i;
        register const u_int16_t *sp;
        u_int32_t sum;
        union {
@@ -163,14 +160,11 @@ static int tcp6_cksum(const struct ip6_hdr *ip6, const struct tcphdr *tp,
                u_int16_t pa[20];
        } phu;
 
-       tlen = ntohs(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;
@@ -179,10 +173,10 @@ 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)
@@ -200,7 +194,7 @@ tcp_print(register const u_char *bp, register u_int length,
        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_int16_t sport, dport, win, urp;
        u_int32_t seq, ack, thseq, thack;
@@ -225,27 +219,27 @@ tcp_print(register const u_char *bp, register u_int length,
                return;
        }
 
-       sport = ntohs(tp->th_sport);
-       dport = ntohs(tp->th_dport);
-
+       sport = EXTRACT_16BITS(&tp->th_sport);
+       dport = EXTRACT_16BITS(&tp->th_dport);
 
        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 ((u_char *)tp + 4 + sizeof(struct rpc_msg) <= snapend &&
+       if (!qflag && hlen >= sizeof(*tp) && hlen <= length) {
+               if ((u_char *)tp + 4 + sizeof(struct sunrpc_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)
+               } else if ((u_char *)tp + 4 + sizeof(struct sunrpc_msg)
                           <= snapend &&
                           sport == NFS_PORT) {
-                       nfsreply_print((u_char *)tp + hlen + 4,length-hlen,
+                       nfsreply_print((u_char *)tp + hlen + 4, length - hlen,
                                       (u_char *)ip);
                        return;
                }
@@ -277,15 +271,25 @@ 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 = (u_int32_t)ntohl(tp->th_seq);
-       ack = (u_int32_t)ntohl(tp->th_ack);
-       win = ntohs(tp->th_win);
-       urp = ntohs(tp->th_urp);
+       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 - 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|
@@ -307,6 +311,7 @@ tcp_print(register const u_char *bp, register u_int length,
 
        if (!Sflag && (flags & TH_ACK)) {
                register struct tcp_seq_hash *th;
+               const void *src, *dst;
                register int rev;
                struct tha tha;
                /*
@@ -319,63 +324,68 @@ tcp_print(register const u_char *bp, register u_int length,
                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) {
-                               int i;
-
-                               for (i = 0; i < 4; i++) {
-                                       if (((u_int32_t *)(&ip6->ip6_src))[i] >
-                                           ((u_int32_t *)(&ip6->ip6_dst))[i]) {
-                                               rev = 1;
-                                               break;
-                                       }
-                               }
+                               if (memcmp(src, dst, sizeof ip6->ip6_dst) > 0)
+                                       rev = 1;
                        }
                        if (rev) {
-                               tha.src = ip6->ip6_dst;
-                               tha.dst = ip6->ip6_src;
+                               memcpy(&tha.src, dst, sizeof ip6->ip6_dst);
+                               memcpy(&tha.dst, src, sizeof ip6->ip6_src);
                                tha.port = dport << 16 | sport;
                        } else {
-                               tha.dst = ip6->ip6_dst;
-                               tha.src = ip6->ip6_src;
+                               memcpy(&tha.dst, dst, sizeof ip6->ip6_dst);
+                               memcpy(&tha.src, src, sizeof ip6->ip6_src);
                                tha.port = sport << 16 | dport;
                        }
                } else {
-                       if (sport > dport ||
-                           (sport == dport &&
-                            ip->ip_src.s_addr > ip->ip_dst.s_addr)) {
+                       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) {
-                               *(struct in_addr *)&tha.src = ip->ip_dst;
-                               *(struct in_addr *)&tha.dst = ip->ip_src;
+                               memcpy(&tha.src, dst, sizeof ip->ip_dst);
+                               memcpy(&tha.dst, src, sizeof ip->ip_src);
                                tha.port = dport << 16 | sport;
                        } else {
-                               *(struct in_addr *)&tha.dst = ip->ip_dst;
-                               *(struct in_addr *)&tha.src = ip->ip_src;
+                               memcpy(&tha.dst, dst, sizeof ip->ip_dst);
+                               memcpy(&tha.src, src, sizeof ip->ip_src);
                                tha.port = sport << 16 | dport;
                        }
                }
 #else
-               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;
-               } else {
-                       tha.src = ip->ip_dst, tha.dst = ip->ip_src;
-                       tha.port = dport << 16 | sport;
+               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)) {
@@ -405,36 +415,43 @@ 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;
        }
 
        if (IP_V(ip) == 4 && vflag && !fragmented) {
-               int sum;
+               u_int16_t sum, tcp_sum;
                if (TTEST2(tp->th_sport, length)) {
                        sum = tcp_cksum(ip, tp, length);
-                       if (sum != 0)
-                               (void)printf(" [bad tcp cksum %x!]", sum);
-                       else
-                               (void)printf(" [tcp sum ok]");
+
+                        (void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
+                       if (sum != 0) {
+                               tcp_sum = EXTRACT_16BITS(&tp->th_sum);
+                               (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 && !fragmented) {
-               int sum;
+               u_int16_t sum,tcp_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]");
+                        (void)printf(", cksum 0x%04x",EXTRACT_16BITS(&tp->th_sum));
+                       if (sum != 0) {
+                               tcp_sum = EXTRACT_16BITS(&tp->th_sum);
+                               (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))
-               (void)printf(" %u:%u(%d)", seq, seq + length, length);
+               (void)printf(" %u:%u(%u)", seq, seq + length, length);
        if (flags & TH_ACK)
                (void)printf(" ack %u", ack);
 
@@ -445,10 +462,12 @@ 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 = '<';
@@ -501,14 +520,13 @@ tcp_print(register const u_char *bp, register u_int length,
                                break;
 
                        case TCPOPT_SACK:
-                               (void)printf("sack");
                                datalen = len - 2;
                                if (datalen % 8 != 0) {
-                                       (void)printf(" malformed sack ");
+                                       (void)printf("malformed sack");
                                } else {
                                        u_int32_t s, e;
 
-                                       (void)printf(" sack %d ", datalen / 8);
+                                       (void)printf("sack %d ", datalen / 8);
                                        for (i = 0; i < datalen; i += 8) {
                                                LENCHECK(i + 4);
                                                s = EXTRACT_32BITS(cp + i);
@@ -523,7 +541,6 @@ tcp_print(register const u_char *bp, register u_int length,
                                                }
                                                (void)printf("{%u:%u}", s, e);
                                        }
-                                       (void)printf(" ");
                                }
                                break;
 
@@ -571,8 +588,36 @@ tcp_print(register const u_char *bp, register u_int length,
                                (void)printf(" %u", EXTRACT_32BITS(cp));
                                break;
 
+                       case TCPOPT_SIGNATURE:
+                               (void)printf("md5:");
+                               datalen = TCP_SIGLEN;
+                               LENCHECK(datalen);
+#ifdef HAVE_LIBCRYPTO
+                               switch (tcp_verify_signature(ip, tp,
+                                   bp + TH_OFF(tp) * 4, length, cp)) {
+
+                               case SIGNATURE_VALID:
+                                       (void)printf("valid");
+                                       break;
+
+                               case SIGNATURE_INVALID:
+                                       (void)printf("invalid");
+                                       break;
+
+                               case CANT_CHECK_SIGNATURE:
+                                       (void)printf("can't check - ");
+                                       for (i = 0; i < TCP_SIGLEN; ++i)
+                                               (void)printf("%02x", cp[i]);
+                                       break;
+                               }
+#else
+                               for (i = 0; i < TCP_SIGLEN; ++i)
+                                       (void)printf("%02x", cp[i]);
+#endif
+                               break;
+
                        default:
-                               (void)printf("opt-%d:", opt);
+                               (void)printf("opt-%u:", opt);
                                datalen = len - 2;
                                for (i = 0; i < datalen; ++i) {
                                        LENCHECK(i);
@@ -615,15 +660,26 @@ tcp_print(register const u_char *bp, register u_int length,
                } else if (sport == BGP_PORT || dport == BGP_PORT)
                        bgp_print(bp, length);
                else if (sport == PPTP_PORT || dport == PPTP_PORT)
-                       pptp_print(bp, length);
+                       pptp_print(bp);
+#ifdef TCPDUMP_DO_SMB
                else if (sport == NETBIOS_SSN_PORT || dport == NETBIOS_SSN_PORT)
                        nbt_tcp_print(bp, length);
-               else if (sport == BXXP_PORT || dport == BXXP_PORT)
-                       bxxp_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)) {
-                       /* TCP DNS query has 2byte length at the head */
-                       ns_print(bp + 2, 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 (length > 0 && (sport == LDP_PORT || dport == LDP_PORT)) {
+                        ldp_print(bp, length);
                }
        }
        return;
@@ -673,3 +729,79 @@ print_tcp_rst_data(register const u_char *sp, u_int length)
        }
        putchar(']');
 }
+
+#ifdef HAVE_LIBCRYPTO
+static int
+tcp_verify_signature(const struct ip *ip, const struct tcphdr *tp,
+    const u_char *data, int length, const u_char *rcvsig)
+{
+        struct tcphdr tp1;
+       u_char sig[TCP_SIGLEN];
+       char zero_proto = 0;
+       MD5_CTX ctx;
+       u_int16_t savecsum, tlen;
+#ifdef INET6
+       struct ip6_hdr *ip6;
+#endif
+       u_int32_t len32;
+       u_int8_t nxt;
+
+       tp1 = *tp;
+
+       if (tcpmd5secret == NULL)
+               return (CANT_CHECK_SIGNATURE);
+
+       MD5_Init(&ctx);
+       /*
+        * Step 1: Update MD5 hash with IP pseudo-header.
+        */
+       if (IP_V(ip) == 4) {
+               MD5_Update(&ctx, (char *)&ip->ip_src, sizeof(ip->ip_src));
+               MD5_Update(&ctx, (char *)&ip->ip_dst, sizeof(ip->ip_dst));
+               MD5_Update(&ctx, (char *)&zero_proto, sizeof(zero_proto));
+               MD5_Update(&ctx, (char *)&ip->ip_p, sizeof(ip->ip_p));
+               tlen = EXTRACT_16BITS(&ip->ip_len) - IP_HL(ip) * 4;
+               tlen = htons(tlen);
+               MD5_Update(&ctx, (char *)&tlen, sizeof(tlen));
+#ifdef INET6
+       } else if (IP_V(ip) == 6) {
+               ip6 = (struct ip6_hdr *)ip;
+               MD5_Update(&ctx, (char *)&ip6->ip6_src, sizeof(ip6->ip6_src));
+               MD5_Update(&ctx, (char *)&ip6->ip6_dst, sizeof(ip6->ip6_dst));
+               len32 = htonl(ntohs(ip6->ip6_plen));
+               MD5_Update(&ctx, (char *)&len32, sizeof(len32));
+               nxt = 0;
+               MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
+               MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
+               MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
+               nxt = IPPROTO_TCP;
+               MD5_Update(&ctx, (char *)&nxt, sizeof(nxt));
+#endif
+       } else
+               return (CANT_CHECK_SIGNATURE);
+
+       /*
+        * Step 2: Update MD5 hash with TCP header, excluding options.
+        * The TCP checksum must be set to zero.
+        */
+       savecsum = tp1.th_sum;
+       tp1.th_sum = 0;
+       MD5_Update(&ctx, (char *)&tp1, sizeof(struct tcphdr));
+       tp1.th_sum = savecsum;
+       /*
+        * Step 3: Update MD5 hash with TCP segment data, if present.
+        */
+       if (length > 0)
+               MD5_Update(&ctx, data, length);
+       /*
+        * Step 4: Update MD5 hash with shared secret.
+        */
+       MD5_Update(&ctx, tcpmd5secret, strlen(tcpmd5secret));
+       MD5_Final(sig, &ctx);
+
+       if (memcmp(rcvsig, sig, TCP_SIGLEN) == 0)
+               return (SIGNATURE_VALID);
+       else
+               return (SIGNATURE_INVALID);
+}
+#endif /* HAVE_LIBCRYPTO */