The Tcpdump Group git mirrors - tcpdump/blob - print-pflog.c

   1 /*
   2  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 /* \summary: OpenBSD packet filter log file printer */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #ifndef HAVE_NET_PFVAR_H
  29 #error "No pf headers available"
  30 #endif
  31 #include <sys/types.h>
  32 #include <sys/socket.h>
  33 #include <net/if.h>
  34 #include <net/pfvar.h>
  35 #include <net/if_pflog.h>
  36
  37 #include "netdissect-stdinc.h"
  38
  39 #include "netdissect.h"
  40 #include "extract.h"
  41
  42
  43 static const struct tok pf_reasons[] = {
  44         { 0,    "0(match)" },
  45         { 1,    "1(bad-offset)" },
  46         { 2,    "2(fragment)" },
  47         { 3,    "3(short)" },
  48         { 4,    "4(normalize)" },
  49         { 5,    "5(memory)" },
  50         { 6,    "6(bad-timestamp)" },
  51         { 7,    "7(congestion)" },
  52         { 8,    "8(ip-option)" },
  53         { 9,    "9(proto-cksum)" },
  54         { 10,   "10(state-mismatch)" },
  55         { 11,   "11(state-insert)" },
  56         { 12,   "12(state-limit)" },
  57         { 13,   "13(src-limit)" },
  58         { 14,   "14(synproxy)" },
  59         { 0,    NULL }
  60 };
  61
  62 static const struct tok pf_actions[] = {
  63         { PF_PASS,              "pass" },
  64         { PF_DROP,              "block" },
  65         { PF_SCRUB,             "scrub" },
  66         { PF_NAT,               "nat" },
  67         { PF_NONAT,             "nat" },
  68         { PF_BINAT,             "binat" },
  69         { PF_NOBINAT,           "binat" },
  70         { PF_RDR,               "rdr" },
  71         { PF_NORDR,             "rdr" },
  72         { PF_SYNPROXY_DROP,     "synproxy-drop" },
  73         { 0,                    NULL }
  74 };
  75
  76 static const struct tok pf_directions[] = {
  77         { PF_INOUT,     "in/out" },
  78         { PF_IN,        "in" },
  79         { PF_OUT,       "out" },
  80         { 0,            NULL }
  81 };
  82
  83 /* For reading capture files on other systems */
  84 #define OPENBSD_AF_INET         2
  85 #define OPENBSD_AF_INET6        24
  86
  87 static void
  88 pflog_print(netdissect_options *ndo, const struct pfloghdr *hdr)
  89 {
  90         uint32_t rulenr, subrulenr;
  91
  92         ndo->ndo_protocol = "pflog";
  93         rulenr = GET_BE_U_4(&hdr->rulenr);
  94         subrulenr = GET_BE_U_4(&hdr->subrulenr);
  95         if (subrulenr == (uint32_t)-1)
  96                 ND_PRINT("rule %u/", rulenr);
  97         else {
  98                 ND_PRINT("rule %u.", rulenr);
  99                 nd_printjnp(ndo, (const u_char*)hdr->ruleset, PFLOG_RULESET_NAME_SIZE);
 100                 ND_PRINT(".%u/", subrulenr);
 101         }
 102
 103         ND_PRINT("%s: %s %s on ",
 104             tok2str(pf_reasons, "unkn(%u)", GET_U_1(&hdr->reason)),
 105             tok2str(pf_actions, "unkn(%u)", GET_U_1(&hdr->action)),
 106             tok2str(pf_directions, "unkn(%u)", GET_U_1(&hdr->dir)));
 107         nd_printjnp(ndo, (const u_char*)hdr->ifname, IFNAMSIZ);
 108         ND_PRINT(": ");
 109 }
 110
 111 void
 112 pflog_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h,
 113                const u_char *p)
 114 {
 115         u_int length = h->len;
 116         u_int hdrlen;
 117         u_int caplen = h->caplen;
 118         const struct pfloghdr *hdr;
 119         uint8_t af;
 120
 121         ndo->ndo_protocol = "pflog";
 122         /* check length */
 123         if (caplen < sizeof(uint8_t)) {
 124                 nd_print_trunc(ndo);
 125                 ndo->ndo_ll_hdr_len += h->caplen;
 126                 return;
 127         }
 128
 129 #define MIN_PFLOG_HDRLEN        45
 130         hdr = (const struct pfloghdr *)p;
 131         if (GET_U_1(&hdr->length) < MIN_PFLOG_HDRLEN) {
 132                 ND_PRINT("[pflog: invalid header length!]");
 133                 ndo->ndo_ll_hdr_len += GET_U_1(&hdr->length);   /* XXX: not really */
 134                 return;
 135         }
 136         hdrlen = BPF_WORDALIGN(hdr->length);
 137
 138         if (caplen < hdrlen) {
 139                 nd_print_trunc(ndo);
 140                 ndo->ndo_ll_hdr_len += hdrlen;  /* XXX: true? */
 141                 return;
 142         }
 143
 144         /* print what we know */
 145         ND_TCHECK_SIZE(hdr);
 146         if (ndo->ndo_eflag)
 147                 pflog_print(ndo, hdr);
 148
 149         /* skip to the real packet */
 150         af = GET_U_1(&hdr->af);
 151         length -= hdrlen;
 152         caplen -= hdrlen;
 153         p += hdrlen;
 154         switch (af) {
 155
 156                 case AF_INET:
 157 #if OPENBSD_AF_INET != AF_INET
 158                 case OPENBSD_AF_INET:           /* XXX: read pcap files */
 159 #endif
 160                         ip_print(ndo, p, length);
 161                         break;
 162
 163 #if defined(AF_INET6) || defined(OPENBSD_AF_INET6)
 164 #ifdef AF_INET6
 165                 case AF_INET6:
 166 #endif /* AF_INET6 */
 167 #if !defined(AF_INET6) || OPENBSD_AF_INET6 != AF_INET6
 168                 case OPENBSD_AF_INET6:          /* XXX: read pcap files */
 169 #endif /* !defined(AF_INET6) || OPENBSD_AF_INET6 != AF_INET6 */
 170                         ip6_print(ndo, p, length);
 171                         break;
 172 #endif /* defined(AF_INET6) || defined(OPENBSD_AF_INET6) */
 173
 174         default:
 175                 /* address family not handled, print raw packet */
 176                 if (!ndo->ndo_eflag)
 177                         pflog_print(ndo, hdr);
 178                 if (!ndo->ndo_suppress_default_print)
 179                         ND_DEFAULTPRINT(p, caplen);
 180         }
 181
 182         ndo->ndo_ll_hdr_len += hdrlen;
 183         return;
 184 trunc:
 185         nd_print_trunc(ndo);
 186         ndo->ndo_ll_hdr_len += hdrlen;
 187 }