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 (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <sys/types.h>
27 #include <sys/errno.h>
28 #include <setjmp.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.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 #include <arpa/inet.h>
42
43 #include "snoop.h"
44
45 extern char *dlc_header;
46 extern jmp_buf xdr_err;
47
48 static char *printip(unsigned char *);
49 static char *addrtoname_align(unsigned char *);
50
51 static char unarp_addr[] = "Unknown";
52 char *opname[] = {
53 "",
54 "ARP Request",
55 "ARP Reply",
56 "REVARP Request",
57 "REVARP Reply",
58 };
59
60 void
61 interpret_arp(int flags, struct arphdr *ap, int alen)
62 {
63 char *line;
64 extern char *src_name, *dst_name;
65 unsigned char *sip, *tip, *sha, *tha;
66 char *smacbuf = NULL, *dmacbuf = NULL;
67 int maclen;
68 ushort_t arpop;
69 boolean_t is_ip = B_FALSE;
70
71 /*
72 * Check that at least the generic ARP header was received.
73 */
74 if (sizeof (struct arphdr) > alen)
75 goto short_packet;
76
77 arpop = ntohs(ap->ar_op);
78 maclen = ap->ar_hln;
79 if (ntohs(ap->ar_pro) == ETHERTYPE_IP)
80 is_ip = B_TRUE;
81
82 sha = (unsigned char *)(ap + 1);
83 sip = sha + maclen;
84 tha = sip + ap->ar_pln;
85 tip = tha + maclen;
86
87 /*
88 * Check that the protocol/hardware addresses were received.
89 */
90 if ((tip + ap->ar_pln) > ((unsigned char *)ap + alen))
91 goto short_packet;
92
93 if (maclen == 0) {
94 smacbuf = dmacbuf = unarp_addr;
95 } else {
96 if (((flags & F_DTAIL) && is_ip) || (arpop == ARPOP_REPLY)) {
97 smacbuf = _link_ntoa(sha, NULL, maclen, IFT_OTHER);
98 if (smacbuf == NULL)
99 pr_err("Warning: malloc failure");
100 }
101
102 if (((flags & F_DTAIL) && is_ip) || (arpop ==
103 REVARP_REQUEST) || (arpop == REVARP_REPLY)) {
104 dmacbuf = _link_ntoa(tha, NULL, maclen, IFT_OTHER);
105 if (dmacbuf == NULL)
106 pr_err("Warning: malloc failure");
107 }
108 }
109
110 src_name = addrtoname_align(sip);
111
112 if (flags & F_SUM) {
113
114 line = get_sum_line();
115
116 switch (arpop) {
117 case ARPOP_REQUEST:
118 (void) snprintf(line, MAXLINE, "ARP C Who is %s ?",
119 printip(tip));
120 break;
121 case ARPOP_REPLY:
122 (void) snprintf(line, MAXLINE, "ARP R %s is %s",
123 printip(sip), smacbuf);
124 dst_name = addrtoname_align(tip);
125 break;
126 case REVARP_REQUEST:
127 (void) snprintf(line, MAXLINE, "RARP C Who is %s ?",
128 dmacbuf);
129 break;
130 case REVARP_REPLY:
131 (void) snprintf(line, MAXLINE, "RARP R %s is %s",
132 dmacbuf, printip(tip));
133 dst_name = addrtoname_align(tip);
134 break;
135 }
136 }
137
138 if (flags & F_DTAIL) {
139 show_header("ARP: ", "ARP/RARP Frame", alen);
140 show_space();
141 (void) snprintf(get_line(0, 0), get_line_remain(),
142 "Hardware type = %d (%s)", ntohs(ap->ar_hrd),
143 arp_htype(ntohs(ap->ar_hrd)));
144 (void) snprintf(get_line(0, 0), get_line_remain(),
145 "Protocol type = %04x (%s)", ntohs(ap->ar_pro),
146 print_ethertype(ntohs(ap->ar_pro)));
147 (void) snprintf(get_line(0, 0), get_line_remain(),
148 "Length of hardware address = %d bytes", ap->ar_hln);
149 (void) snprintf(get_line(0, 0), get_line_remain(),
150 "Length of protocol address = %d bytes", ap->ar_pln);
151 (void) snprintf(get_line(0, 0), get_line_remain(),
152 "Opcode %d (%s)", arpop,
153 (arpop > REVARP_REPLY) ? opname[0] : opname[arpop]);
154
155 if (is_ip) {
156 (void) snprintf(get_line(0, 0), get_line_remain(),
157 "Sender's hardware address = %s", smacbuf);
158 (void) snprintf(get_line(0, 0), get_line_remain(),
159 "Sender's protocol address = %s",
160 printip(sip));
161 (void) snprintf(get_line(0, 0), get_line_remain(),
162 "Target hardware address = %s",
163 arpop == ARPOP_REQUEST ? "?" : dmacbuf);
164 (void) snprintf(get_line(0, 0), get_line_remain(),
165 "Target protocol address = %s",
166 arpop == REVARP_REQUEST ? "?" :
167 printip(tip));
168 }
169 show_trailer();
170 }
171
172 if (maclen != 0) {
173 free(smacbuf);
174 free(dmacbuf);
175 }
176 return;
177
178 short_packet:
179 if (flags & F_SUM) {
180 (void) snprintf(get_sum_line(), MAXLINE,
181 "ARP (short packet)");
182 } else if (flags & F_DTAIL) {
183 show_header("ARP: ", "ARP/RARP Frame", alen);
184 show_space();
185 (void) snprintf(get_line(0, 0), get_line_remain(),
186 "ARP (short packet)");
187 }
188 }
189
190 char *
191 printip(unsigned char *p)
192 {
193 static char buff[MAXHOSTNAMELEN + 32];
194 char *ap, *np;
195 struct in_addr a;
196
197 memcpy(&a, p, 4);
198 ap = (char *)inet_ntoa(a);
199 np = (char *)addrtoname(AF_INET, &a);
200 (void) snprintf(buff, MAXHOSTNAMELEN, "%s, %s", ap, np);
201 return (buff);
202 }
203
204 char *
205 addrtoname_align(unsigned char *p)
206 {
207 struct in_addr a;
208
209 memcpy(&a, p, 4);
210 return ((char *)addrtoname(AF_INET, &a));
211 }
212
213 /*
214 * These numbers are assigned by the IANA. See the arp-parameters registry.
215 * Only those values that are used within Solaris have #defines.
216 */
217 const char *
218 arp_htype(int t)
219 {
220 switch (t) {
221 case ARPHRD_ETHER:
222 return ("Ethernet (10Mb)");
223 case 2:
224 return ("Experimental Ethernet (3Mb)");
225 case 3:
226 return ("Amateur Radio AX.25");
227 case 4:
228 return ("Proteon ProNET Token Ring");
229 case 5:
230 return ("Chaos");
231 case ARPHRD_IEEE802:
232 return ("IEEE 802");
233 case 7:
234 return ("ARCNET");
235 case 8:
236 return ("Hyperchannel");
237 case 9:
238 return ("Lanstar");
239 case 10:
240 return ("Autonet");
241 case 11:
242 return ("LocalTalk");
243 case 12:
244 return ("LocalNet");
245 case 13:
246 return ("Ultra Link");
247 case 14:
248 return ("SMDS");
249 case ARPHRD_FRAME:
250 return ("Frame Relay");
251 case ARPHRD_ATM:
252 return ("ATM");
253 case ARPHRD_HDLC:
254 return ("HDLC");
255 case ARPHRD_FC:
256 return ("Fibre Channel");
257 case ARPHRD_IPATM:
258 return ("IP-ATM");
259 case ARPHRD_METRICOM:
260 return ("Metricom");
261 case ARPHRD_TUNNEL:
262 return ("Tunnel");
263 case ARPHRD_IB:
264 return ("IPIB");
265 };
266 return ("UNKNOWN");
267 }