1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000 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: Apple's DLT_PKTAP printer */ 23 24 #ifdef HAVE_CONFIG_H 25 #include "config.h" 26 #endif 27 28 #include <netdissect-stdinc.h> 29 30 #include "netdissect.h" 31 #include "extract.h" 32 33 #ifdef DLT_PKTAP 34 35 /* 36 * XXX - these are little-endian in the captures I've seen, but Apple 37 * no longer make any big-endian machines (Macs use x86, iOS machines 38 * use ARM and run it little-endian), so that might be by definition 39 * or they might be host-endian. 40 * 41 * If a big-endian PKTAP file ever shows up, and it comes from a 42 * big-endian machine, presumably these are host-endian, and we need 43 * to just fetch the fields directly in tcpdump but byte-swap them 44 * to host byte order in libpcap. 45 */ 46 typedef struct pktap_header { 47 uint32_t pkt_len; /* length of pktap header */ 48 uint32_t pkt_rectype; /* type of record */ 49 uint32_t pkt_dlt; /* DLT type of this packet */ 50 char pkt_ifname[24]; /* interface name */ 51 uint32_t pkt_flags; 52 uint32_t pkt_pfamily; /* "protocol family" */ 53 uint32_t pkt_llhdrlen; /* link-layer header length? */ 54 uint32_t pkt_lltrlrlen; /* link-layer trailer length? */ 55 uint32_t pkt_pid; /* process ID */ 56 char pkt_cmdname[20]; /* command name */ 57 uint32_t pkt_svc_class; /* "service class" */ 58 uint16_t pkt_iftype; /* "interface type" */ 59 uint16_t pkt_ifunit; /* unit number of interface? */ 60 uint32_t pkt_epid; /* "effective process ID" */ 61 char pkt_ecmdname[20]; /* "effective command name" */ 62 } pktap_header_t; 63 64 /* 65 * Record types. 66 */ 67 #define PKT_REC_NONE 0 /* nothing follows the header */ 68 #define PKT_REC_PACKET 1 /* a packet follows the header */ 69 70 static inline void 71 pktap_header_print(netdissect_options *ndo, const u_char *bp, u_int length) 72 { 73 const pktap_header_t *hdr; 74 uint32_t dlt, hdrlen; 75 const char *dltname; 76 77 hdr = (const pktap_header_t *)bp; 78 79 dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt); 80 hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len); 81 dltname = pcap_datalink_val_to_name(dlt); 82 if (!ndo->ndo_qflag) { 83 ND_PRINT((ndo,"DLT %s (%d) len %d", 84 (dltname != NULL ? dltname : "UNKNOWN"), dlt, hdrlen)); 85 } else { 86 ND_PRINT((ndo,"%s", (dltname != NULL ? dltname : "UNKNOWN"))); 87 } 88 89 ND_PRINT((ndo, ", length %u: ", length)); 90 } 91 92 /* 93 * This is the top level routine of the printer. 'p' points 94 * to the ether header of the packet, 'h->ts' is the timestamp, 95 * 'h->len' is the length of the packet off the wire, and 'h->caplen' 96 * is the number of bytes actually captured. 97 */ 98 u_int 99 pktap_if_print(netdissect_options *ndo, 100 const struct pcap_pkthdr *h, const u_char *p) 101 { 102 uint32_t dlt, hdrlen, rectype; 103 u_int caplen = h->caplen; 104 u_int length = h->len; 105 if_printer printer; 106 const pktap_header_t *hdr; 107 struct pcap_pkthdr nhdr; 108 109 if (caplen < sizeof(pktap_header_t) || length < sizeof(pktap_header_t)) { 110 ND_PRINT((ndo, "[|pktap]")); 111 return (0); 112 } 113 hdr = (const pktap_header_t *)p; 114 dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt); 115 hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len); 116 if (hdrlen < sizeof(pktap_header_t)) { 117 /* 118 * Claimed header length < structure length. 119 * XXX - does this just mean some fields aren't 120 * being supplied, or is it truly an error (i.e., 121 * is the length supplied so that the header can 122 * be expanded in the future)? 123 */ 124 ND_PRINT((ndo, "[|pktap]")); 125 return (0); 126 } 127 if (caplen < hdrlen || length < hdrlen) { 128 ND_PRINT((ndo, "[|pktap]")); 129 return (hdrlen); 130 } 131 132 if (ndo->ndo_eflag) 133 pktap_header_print(ndo, p, length); 134 135 length -= hdrlen; 136 caplen -= hdrlen; 137 p += hdrlen; 138 139 rectype = EXTRACT_LE_32BITS(&hdr->pkt_rectype); 140 switch (rectype) { 141 142 case PKT_REC_NONE: 143 ND_PRINT((ndo, "no data")); 144 break; 145 146 case PKT_REC_PACKET: 147 if ((printer = lookup_printer(dlt)) != NULL) { 148 nhdr = *h; 149 nhdr.caplen = caplen; 150 nhdr.len = length; 151 hdrlen += printer(ndo, &nhdr, p); 152 } else { 153 if (!ndo->ndo_eflag) 154 pktap_header_print(ndo, (const u_char *)hdr, 155 length + hdrlen); 156 157 if (!ndo->ndo_suppress_default_print) 158 ND_DEFAULTPRINT(p, caplen); 159 } 160 break; 161 } 162 163 return (hdrlen); 164 } 165 166 /* 167 * Local Variables: 168 * c-style: whitesmith 169 * c-basic-offset: 8 170 * End: 171 */ 172 173 #endif /* DLT_PKTAP */ 174
