1 /* $OpenBSD: print-null.c,v 1.23 2018/10/22 16:12:45 kn Exp $ */ 2 3 /* 4 * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that: (1) source code distributions 9 * retain the above copyright notice and this paragraph in its entirety, (2) 10 * distributions including binary code include the above copyright notice and 11 * this paragraph in its entirety in the documentation or other materials 12 * provided with the distribution, and (3) all advertising materials mentioning 13 * features or use of this software display the following acknowledgement: 14 * ``This product includes software developed by the University of California, 15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 16 * the University nor the names of its contributors may be used to endorse 17 * or promote products derived from this software without specific prior 18 * written permission. 19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 22 */ 23 24 #include <sys/time.h> 25 #include <sys/socket.h> 26 #include <sys/file.h> 27 #include <sys/ioctl.h> 28 29 struct mbuf; 30 struct rtentry; 31 #include <net/if.h> 32 33 #include <netinet/in.h> 34 #include <netinet/ip.h> 35 #include <netinet/ip6.h> 36 #include <netinet/if_ether.h> 37 #include <netinet/ip_var.h> 38 #include <netinet/udp.h> 39 #include <netinet/udp_var.h> 40 #include <netinet/tcp.h> 41 42 #include <pcap.h> 43 #include <stdio.h> 44 #include <string.h> 45 46 #include "interface.h" 47 #include "addrtoname.h" 48 49 #ifndef AF_NS 50 #define AF_NS 6 /* XEROX NS protocols */ 51 #endif 52 53 /* 54 * The DLT_NULL packet header is 4 bytes long. It contains a host 55 * order 32 bit integer that specifies the family, e.g. AF_INET 56 */ 57 #define NULL_HDRLEN 4 58 59 static void 60 null_print(const u_char *p, const struct ip *ip, u_int length) 61 { 62 u_int family; 63 64 memcpy((char *)&family, (char *)p, sizeof(family)); 65 66 if (nflag && family != AF_LINK) { 67 /* XXX just dump the header */ 68 return; 69 } 70 switch (family) { 71 72 case AF_INET: 73 printf("ip: "); 74 break; 75 76 case AF_INET6: 77 printf("ip6: "); 78 break; 79 80 case AF_NS: 81 printf("ns: "); 82 break; 83 84 #ifdef __OpenBSD__ 85 case AF_LINK: 86 ether_print(p + NULL_HDRLEN, length); 87 break; 88 #endif 89 case AF_MPLS: 90 printf("mpls: "); 91 break; 92 93 default: 94 printf("AF %d: ", family); 95 break; 96 } 97 } 98 99 void 100 loop_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p) 101 { 102 *(u_int *)p = ntohl(*(u_int *)p); 103 104 null_if_print(user, h, p); 105 } 106 107 void 108 null_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p) 109 { 110 u_int length = h->len; 111 u_int caplen = h->caplen; 112 u_int family = *(u_int *)p; 113 114 #ifdef __OpenBSD__ 115 struct ether_header *ep; 116 u_short ether_type; 117 extern u_short extracted_ethertype; 118 #endif 119 120 ts_print(&h->ts); 121 122 /* 123 * Some printers want to get back at the link level addresses, 124 * and/or check that they're not walking off the end of the packet. 125 * Rather than pass them all the way down, we set these globals. 126 */ 127 packetp = p; 128 snapend = p + caplen; 129 130 length -= NULL_HDRLEN; 131 132 if (eflag) 133 null_print(p, (struct ip *)(p + NULL_HDRLEN), length); 134 135 switch (family) { 136 case AF_INET: 137 ip_print(p + NULL_HDRLEN, length); 138 break; 139 140 case AF_INET6: 141 ip6_print(p + NULL_HDRLEN, length); 142 break; 143 144 case AF_MPLS: 145 mpls_print(p + NULL_HDRLEN, length); 146 break; 147 148 #ifdef __OpenBSD__ 149 case AF_LINK: 150 if (caplen < sizeof(struct ether_header) + NULL_HDRLEN) { 151 printf("[|ether]"); 152 goto out; 153 } 154 155 length -= sizeof(struct ether_header); 156 caplen -= sizeof(struct ether_header); 157 ep = (struct ether_header *)(p + NULL_HDRLEN); 158 p += NULL_HDRLEN + sizeof(struct ether_header); 159 packetp += sizeof(struct ether_header); 160 ether_type = ntohs(ep->ether_type); 161 162 extracted_ethertype = 0; 163 if (ether_type <= ETHERMTU) { 164 /* Try to print the LLC-layer header & higher layers */ 165 if (llc_print(p, length, caplen, ESRC(ep), 166 EDST(ep)) == 0) { 167 /* ether_type not known, print raw packet */ 168 if (!eflag) 169 ether_print((u_char *)ep, length); 170 if (extracted_ethertype) { 171 printf("(LLC %s) ", 172 etherproto_string(htons(extracted_ethertype))); 173 } 174 if (!xflag && !qflag) 175 default_print(p, caplen - NULL_HDRLEN); 176 } 177 } else if (ether_encap_print(ether_type, p, length, 178 caplen) == 0) { 179 /* ether_type not known, print raw packet */ 180 if (!eflag) 181 ether_print((u_char *)ep, length + 182 sizeof(*ep)); 183 if (!xflag && !qflag) 184 default_print(p, caplen - NULL_HDRLEN); 185 } 186 break; 187 #endif /* __OpenBSD__ */ 188 } 189 190 if (xflag) 191 default_print((const u_char *)(packetp + NULL_HDRLEN), 192 caplen - NULL_HDRLEN); 193 out: 194 putchar('\n'); 195 } 196 197