1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 1991-2001, 2003 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 #include <sys/types.h> 30 #include <sys/errno.h> 31 #include <setjmp.h> 32 #include <sys/socket.h> 33 #include <net/if.h> 34 #include <net/if_arp.h> 35 #include <netinet/in_systm.h> 36 #include <netinet/in.h> 37 #include <netinet/ip.h> 38 #include <netinet/if_ether.h> 39 #include <netdb.h> 40 #include <net/if_types.h> 41 42 #include "snoop.h" 43 44 extern char *dlc_header; 45 extern jmp_buf xdr_err; 46 47 static char *printip(unsigned char *); 48 static char *addrtoname_align(unsigned char *); 49 50 static char unarp_addr[] = "Unknown"; 51 char *opname[] = { 52 "", 53 "ARP Request", 54 "ARP Reply", 55 "REVARP Request", 56 "REVARP Reply", 57 }; 58 59 void 60 interpret_arp(int flags, struct arphdr *ap, int alen) 61 { 62 char *line; 63 extern char *src_name, *dst_name; 64 unsigned char *sip, *tip, *sha, *tha; 65 char *smacbuf = NULL, *dmacbuf = NULL; 66 int maclen; 67 ushort_t arpop; 68 boolean_t is_ip = B_FALSE; 69 70 /* 71 * Check that at least the generic ARP header was received. 72 */ 73 if (sizeof (struct arphdr) > alen) 74 goto short_packet; 75 76 arpop = ntohs(ap->ar_op); 77 maclen = ap->ar_hln; 78 if (ntohs(ap->ar_pro) == ETHERTYPE_IP) 79 is_ip = B_TRUE; 80 81 sha = (unsigned char *)(ap + 1); 82 sip = sha + maclen; 83 tha = sip + ap->ar_pln; 84 tip = tha + maclen; 85 86 /* 87 * Check that the protocol/hardware addresses were received. 88 */ 89 if ((tip + ap->ar_pln) > ((unsigned char *)ap + alen)) 90 goto short_packet; 91 92 if (maclen == 0) { 93 smacbuf = dmacbuf = unarp_addr; 94 } else { 95 if (((flags & F_DTAIL) && is_ip) || (arpop == ARPOP_REPLY)) { 96 smacbuf = _link_ntoa(sha, NULL, maclen, IFT_OTHER); 97 if (smacbuf == NULL) 98 pr_err("Warning: malloc failure"); 99 } 100 101 if (((flags & F_DTAIL) && is_ip) || (arpop == 102 REVARP_REQUEST) || (arpop == REVARP_REPLY)) { 103 dmacbuf = _link_ntoa(tha, NULL, maclen, IFT_OTHER); 104 if (dmacbuf == NULL) 105 pr_err("Warning: malloc failure"); 106 } 107 } 108 109 src_name = addrtoname_align(sip); 110 111 if (flags & F_SUM) { 112 113 line = get_sum_line(); 114 115 switch (arpop) { 116 case ARPOP_REQUEST: 117 (void) snprintf(line, MAXLINE, "ARP C Who is %s ?", 118 printip(tip)); 119 break; 120 case ARPOP_REPLY: 121 (void) snprintf(line, MAXLINE, "ARP R %s is %s", 122 printip(sip), smacbuf); 123 dst_name = addrtoname_align(tip); 124 break; 125 case REVARP_REQUEST: 126 (void) snprintf(line, MAXLINE, "RARP C Who is %s ?", 127 dmacbuf); 128 break; 129 case REVARP_REPLY: 130 (void) snprintf(line, MAXLINE, "RARP R %s is %s", 131 dmacbuf, printip(tip)); 132 dst_name = addrtoname_align(tip); 133 break; 134 } 135 } 136 137 if (flags & F_DTAIL) { 138 show_header("ARP: ", "ARP/RARP Frame", alen); 139 show_space(); 140 (void) snprintf(get_line(0, 0), get_line_remain(), 141 "Hardware type = %d", ntohs(ap->ar_hrd)); 142 (void) snprintf(get_line(0, 0), get_line_remain(), 143 "Protocol type = %04x (%s)", ntohs(ap->ar_pro), 144 print_ethertype(ntohs(ap->ar_pro))); 145 (void) snprintf(get_line(0, 0), get_line_remain(), 146 "Length of hardware address = %d bytes", ap->ar_hln); 147 (void) snprintf(get_line(0, 0), get_line_remain(), 148 "Length of protocol address = %d bytes", ap->ar_pln); 149 (void) snprintf(get_line(0, 0), get_line_remain(), 150 "Opcode %d (%s)", arpop, 151 (arpop > REVARP_REPLY) ? opname[0] : opname[arpop]); 152 153 if (is_ip) { 154 (void) snprintf(get_line(0, 0), get_line_remain(), 155 "Sender's hardware address = %s", smacbuf); 156 (void) snprintf(get_line(0, 0), get_line_remain(), 157 "Sender's protocol address = %s", 158 printip(sip)); 159 (void) snprintf(get_line(0, 0), get_line_remain(), 160 "Target hardware address = %s", 161 arpop == ARPOP_REQUEST ? "?" : dmacbuf); 162 (void) snprintf(get_line(0, 0), get_line_remain(), 163 "Target protocol address = %s", 164 arpop == REVARP_REQUEST ? "?" : 165 printip(tip)); 166 } 167 show_trailer(); 168 } 169 170 if (maclen != 0) { 171 free(smacbuf); 172 free(dmacbuf); 173 } 174 return; 175 176 short_packet: 177 if (flags & F_SUM) { 178 (void) snprintf(get_sum_line(), MAXLINE, 179 "ARP (short packet)"); 180 } else if (flags & F_DTAIL) { 181 show_header("ARP: ", "ARP/RARP Frame", alen); 182 show_space(); 183 (void) snprintf(get_line(0, 0), get_line_remain(), 184 "ARP (short packet)"); 185 } 186 } 187 188 char * 189 printip(unsigned char *p) 190 { 191 static char buff[MAXHOSTNAMELEN + 32]; 192 char *ap, *np; 193 struct in_addr a; 194 195 memcpy(&a, p, 4); 196 ap = (char *)inet_ntoa(a); 197 np = (char *)addrtoname(AF_INET, &a); 198 (void) snprintf(buff, MAXHOSTNAMELEN, "%s, %s", ap, np); 199 return (buff); 200 } 201 202 char * 203 addrtoname_align(unsigned char *p) 204 { 205 struct in_addr a; 206 207 memcpy(&a, p, 4); 208 return ((char *)addrtoname(AF_INET, &a)); 209 } 210