1 /* 2 * Copyright (c) 2013, Petar Alilovic, 3 * Faculty of Electrical Engineering and Computing, University of Zagreb 4 * All rights reserved 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * * Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * * Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY 16 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY 19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25 * DAMAGE. 26 */ 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <tcpdump-stdinc.h> 33 34 #include <stdio.h> 35 #include <pcap.h> 36 37 #include "netdissect.h" 38 #include "interface.h" 39 40 #include "nflog.h" 41 42 #ifdef DLT_NFLOG 43 44 #define NFULA_PAYLOAD 9 45 46 static const struct tok nflog_values[] = { 47 { AF_INET, "IPv4" }, 48 { AF_INET6, "IPv6" }, 49 { 0, NULL } 50 }; 51 52 static inline void 53 nflog_hdr_print(struct netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length) 54 { 55 ND_PRINT((ndo, "version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid))); 56 57 if (!ndo->ndo_qflag) { 58 ND_PRINT((ndo,", family %s (%d)", 59 tok2str(nflog_values, "Unknown", 60 hdr->nflog_family), 61 hdr->nflog_family)); 62 } else { 63 ND_PRINT((ndo,", %s", 64 tok2str(nflog_values, 65 "Unknown NFLOG (0x%02x)", 66 hdr->nflog_family))); 67 } 68 69 ND_PRINT((ndo, ", length %u: ", length)); 70 } 71 72 u_int 73 nflog_if_print(struct netdissect_options *ndo, 74 const struct pcap_pkthdr *h, const u_char *p) 75 { 76 const nflog_hdr_t *hdr = (const nflog_hdr_t *)p; 77 const nflog_tlv_t *tlv; 78 u_int16_t size; 79 u_int16_t h_size = sizeof(nflog_hdr_t); 80 u_int caplen = h->caplen; 81 u_int length = h->len; 82 83 if (caplen < (int) sizeof(nflog_hdr_t) || length < (int) sizeof(nflog_hdr_t)) { 84 ND_PRINT((ndo, "[|nflog]")); 85 return h_size; 86 } 87 88 if (!(hdr->nflog_version) == 0) { 89 ND_PRINT((ndo, "version %u (unknown)", hdr->nflog_version)); 90 return h_size; 91 } 92 93 if (ndo->ndo_eflag) 94 nflog_hdr_print(ndo, hdr, length); 95 96 length -= sizeof(nflog_hdr_t); 97 caplen -= sizeof(nflog_hdr_t); 98 p += sizeof(nflog_hdr_t); 99 100 do { 101 tlv = (const nflog_tlv_t *) p; 102 size = tlv->tlv_length; 103 104 if (size % 4 != 0) 105 size += 4 - size % 4; 106 107 h_size = h_size + size; 108 109 /* wrong size of the packet */ 110 if (size > length || size == 0) 111 return h_size; 112 113 p += size; 114 length = length - size; 115 caplen = caplen - size; 116 117 } while (tlv->tlv_type != NFULA_PAYLOAD); 118 119 /* dont skip payload just tlv length and type */ 120 p = p - size + 4; 121 length += size - 4; 122 caplen += size - 4; 123 h_size -= length; 124 125 switch (hdr->nflog_family) { 126 127 case AF_INET: 128 ip_print(ndo, p, length); 129 break; 130 131 #ifdef INET6 132 case AF_INET6: 133 ip6_print(ndo, p, length); 134 break; 135 #endif /*INET6*/ 136 137 default: 138 if (!ndo->ndo_eflag) 139 nflog_hdr_print(ndo, hdr, 140 length + sizeof(nflog_hdr_t)); 141 142 if (!ndo->ndo_suppress_default_print) 143 ndo->ndo_default_print(ndo, p, caplen); 144 break; 145 } 146 147 return h_size; 148 } 149 150 #endif /* DLT_NFLOG */ 151