1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 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 #ifndef lint 23 static char rcsid[] = 24 "@(#) $Header: print-arp.c,v 1.39 96/07/17 14:56:17 leres Exp $ (LBL)"; 25 #endif 26 27 #include <sys/param.h> 28 #include <sys/time.h> 29 #include <sys/socket.h> 30 31 #if __STDC__ 32 struct mbuf; 33 struct rtentry; 34 #endif 35 #include <net/if.h> 36 37 #include <netinet/in.h> 38 #include <netinet/if_ether.h> 39 40 #include <stdio.h> 41 #include <string.h> 42 43 #include "interface.h" 44 #include "addrtoname.h" 45 #include "ethertype.h" 46 #include "extract.h" /* must come after interface.h */ 47 48 /* Compatibility */ 49 #ifndef REVARP_REQUEST 50 #define REVARP_REQUEST 3 51 #endif 52 #ifndef REVARP_REPLY 53 #define REVARP_REPLY 4 54 #endif 55 56 static u_char ezero[6]; 57 58 void 59 arp_print(register const u_char *bp, u_int length, u_int caplen) 60 { 61 register const struct ether_arp *ap; 62 register const struct ether_header *eh; 63 register u_short pro, hrd, op; 64 65 ap = (struct ether_arp *)bp; 66 if ((u_char *)(ap + 1) > snapend) { 67 printf("[|arp]"); 68 return; 69 } 70 if (length < sizeof(struct ether_arp)) { 71 (void)printf("truncated-arp"); 72 default_print((u_char *)ap, length); 73 return; 74 } 75 76 pro = EXTRACT_16BITS(&ap->arp_pro); 77 hrd = EXTRACT_16BITS(&ap->arp_hrd); 78 op = EXTRACT_16BITS(&ap->arp_op); 79 80 if ((pro != ETHERTYPE_IP && pro != ETHERTYPE_TRAIL) 81 || ap->arp_hln != sizeof(SHA(ap)) 82 || ap->arp_pln != sizeof(SPA(ap))) { 83 (void)printf("arp-#%d for proto #%d (%d) hardware #%d (%d)", 84 op, pro, ap->arp_pln, 85 hrd, ap->arp_hln); 86 return; 87 } 88 if (pro == ETHERTYPE_TRAIL) 89 (void)printf("trailer-"); 90 eh = (struct ether_header *)packetp; 91 switch (op) { 92 93 case ARPOP_REQUEST: 94 (void)printf("arp who-has %s", ipaddr_string(TPA(ap))); 95 if (memcmp((char *)ezero, (char *)THA(ap), 6) != 0) 96 (void)printf(" (%s)", etheraddr_string(THA(ap))); 97 (void)printf(" tell %s", ipaddr_string(SPA(ap))); 98 if (memcmp((char *)ESRC(eh), (char *)SHA(ap), 6) != 0) 99 (void)printf(" (%s)", etheraddr_string(SHA(ap))); 100 break; 101 102 case ARPOP_REPLY: 103 (void)printf("arp reply %s", ipaddr_string(SPA(ap))); 104 if (memcmp((char *)ESRC(eh), (char *)SHA(ap), 6) != 0) 105 (void)printf(" (%s)", etheraddr_string(SHA(ap))); 106 (void)printf(" is-at %s", etheraddr_string(SHA(ap))); 107 if (memcmp((char *)EDST(eh), (char *)THA(ap), 6) != 0) 108 (void)printf(" (%s)", etheraddr_string(THA(ap))); 109 break; 110 111 case REVARP_REQUEST: 112 (void)printf("rarp who-is %s tell %s", 113 etheraddr_string(THA(ap)), 114 etheraddr_string(SHA(ap))); 115 break; 116 117 case REVARP_REPLY: 118 (void)printf("rarp reply %s at %s", 119 etheraddr_string(THA(ap)), 120 ipaddr_string(TPA(ap))); 121 break; 122 123 default: 124 (void)printf("arp-#%d", op); 125 default_print((u_char *)ap, caplen); 126 return; 127 } 128 if (hrd != ARPHRD_ETHER) 129 printf(" hardware #%d", ap->arp_hrd); 130 } 131