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 #define NETDISSECT_REWORKED 29 #ifdef HAVE_CONFIG_H 30 #include "config.h" 31 #endif 32 33 #include <tcpdump-stdinc.h> 34 35 #include "interface.h" 36 37 #if defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H) 38 #include <pcap/nflog.h> 39 40 static const struct tok nflog_values[] = { 41 { AF_INET, "IPv4" }, 42 #ifdef INET6 43 { AF_INET6, "IPv6" }, 44 #endif /*INET6*/ 45 { 0, NULL } 46 }; 47 48 static inline void 49 nflog_hdr_print(netdissect_options *ndo, const nflog_hdr_t *hdr, u_int length) 50 { 51 ND_PRINT((ndo, "version %d, resource ID %d", hdr->nflog_version, ntohs(hdr->nflog_rid))); 52 53 if (!ndo->ndo_qflag) { 54 ND_PRINT((ndo,", family %s (%d)", 55 tok2str(nflog_values, "Unknown", 56 hdr->nflog_family), 57 hdr->nflog_family)); 58 } else { 59 ND_PRINT((ndo,", %s", 60 tok2str(nflog_values, 61 "Unknown NFLOG (0x%02x)", 62 hdr->nflog_family))); 63 } 64 65 ND_PRINT((ndo, ", length %u: ", length)); 66 } 67 68 u_int 69 nflog_if_print(netdissect_options *ndo, 70 const struct pcap_pkthdr *h, const u_char *p) 71 { 72 const nflog_hdr_t *hdr = (const nflog_hdr_t *)p; 73 const nflog_tlv_t *tlv; 74 uint16_t size; 75 uint16_t h_size = sizeof(nflog_hdr_t); 76 u_int caplen = h->caplen; 77 u_int length = h->len; 78 79 if (caplen < (int) sizeof(nflog_hdr_t) || length < (int) sizeof(nflog_hdr_t)) { 80 ND_PRINT((ndo, "[|nflog]")); 81 return h_size; 82 } 83 84 if (!(hdr->nflog_version) == 0) { 85 ND_PRINT((ndo, "version %u (unknown)", hdr->nflog_version)); 86 return h_size; 87 } 88 89 if (ndo->ndo_eflag) 90 nflog_hdr_print(ndo, hdr, length); 91 92 p += sizeof(nflog_hdr_t); 93 length -= sizeof(nflog_hdr_t); 94 caplen -= sizeof(nflog_hdr_t); 95 96 while (length > 0) { 97 /* We have some data. Do we have enough for the TLV header? */ 98 if (caplen < sizeof(nflog_tlv_t) || length < sizeof(nflog_tlv_t)) { 99 /* No. */ 100 ND_PRINT((ndo, "[|nflog]")); 101 return h_size; 102 } 103 104 tlv = (const nflog_tlv_t *) p; 105 size = tlv->tlv_length; 106 if (size % 4 != 0) 107 size += 4 - size % 4; 108 109 /* Is the TLV's length less than the minimum? */ 110 if (size < sizeof(nflog_tlv_t)) { 111 /* Yes. Give up now. */ 112 ND_PRINT((ndo, "[|nflog]")); 113 return h_size; 114 } 115 116 /* Do we have enough data for the full TLV? */ 117 if (caplen < size || length < size) { 118 /* No. */ 119 ND_PRINT((ndo, "[|nflog]")); 120 return h_size; 121 } 122 123 if (tlv->tlv_type == NFULA_PAYLOAD) { 124 /* 125 * This TLV's data is the packet payload. 126 * Skip past the TLV header, and break out 127 * of the loop so we print the packet data. 128 */ 129 p += sizeof(nflog_tlv_t); 130 h_size += sizeof(nflog_tlv_t); 131 length -= sizeof(nflog_tlv_t); 132 caplen -= sizeof(nflog_tlv_t); 133 break; 134 } 135 136 p += size; 137 h_size += size; 138 length -= size; 139 caplen -= size; 140 } 141 142 switch (hdr->nflog_family) { 143 144 case AF_INET: 145 ip_print(ndo, p, length); 146 break; 147 148 #ifdef AF_INET6 149 case AF_INET6: 150 ip6_print(ndo, p, length); 151 break; 152 #endif /* AF_INET6 */ 153 154 default: 155 if (!ndo->ndo_eflag) 156 nflog_hdr_print(ndo, hdr, 157 length + sizeof(nflog_hdr_t)); 158 159 if (!ndo->ndo_suppress_default_print) 160 ND_DEFAULTPRINT(p, caplen); 161 break; 162 } 163 164 return h_size; 165 } 166 167 #endif /* defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H) */ 168