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 #pragma ident "%Z%%M% %I% %E% SMI"
27
28 #include <sys/types.h>
29 #include <sys/errno.h>
30 #include <setjmp.h>
31 #include <sys/socket.h>
32 #include <net/if.h>
33 #include <net/if_arp.h>
34 #include <netinet/in_systm.h>
35 #include <netinet/in.h>
36 #include <netinet/ip.h>
37 #include <netinet/if_ether.h>
38 #include <netdb.h>
39 #include <net/if_types.h>
40
41 #include "snoop.h"
42
43 extern char *dlc_header;
44 extern jmp_buf xdr_err;
45
46 static char *printip(unsigned char *);
47 static char *addrtoname_align(unsigned char *);
48
49 static char unarp_addr[] = "Unknown";
50 char *opname[] = {
51 "",
52 "ARP Request",
53 "ARP Reply",
54 "REVARP Request",
55 "REVARP Reply",
56 };
57
58 void
59 interpret_arp(int flags, struct arphdr *ap, int alen)
60 {
61 char *line;
62 extern char *src_name, *dst_name;
63 unsigned char *sip, *tip, *sha, *tha;
64 char *smacbuf = NULL, *dmacbuf = NULL;
65 int maclen;
66 ushort_t arpop;
67 boolean_t is_ip = B_FALSE;
68
69 /*
70 * Check that at least the generic ARP header was received.
71 */
72 if (sizeof (struct arphdr) > alen)
73 goto short_packet;
74
75 arpop = ntohs(ap->ar_op);
76 maclen = ap->ar_hln;
77 if (ntohs(ap->ar_pro) == ETHERTYPE_IP)
78 is_ip = B_TRUE;
79
80 sha = (unsigned char *)(ap + 1);
81 sip = sha + maclen;
82 tha = sip + ap->ar_pln;
83 tip = tha + maclen;
84
85 /*
86 * Check that the protocol/hardware addresses were received.
87 */
88 if ((tip + ap->ar_pln) > ((unsigned char *)ap + alen))
89 goto short_packet;
90
91 if (maclen == 0) {
92 smacbuf = dmacbuf = unarp_addr;
93 } else {
94 if (((flags & F_DTAIL) && is_ip) || (arpop == ARPOP_REPLY)) {
95 smacbuf = _link_ntoa(sha, NULL, maclen, IFT_OTHER);
96 if (smacbuf == NULL)
97 pr_err("Warning: malloc failure");
98 }
99
100 if (((flags & F_DTAIL) && is_ip) || (arpop ==
101 REVARP_REQUEST) || (arpop == REVARP_REPLY)) {
102 dmacbuf = _link_ntoa(tha, NULL, maclen, IFT_OTHER);
103 if (dmacbuf == NULL)
104 pr_err("Warning: malloc failure");
105 }
106 }
107
108 src_name = addrtoname_align(sip);
109
110 if (flags & F_SUM) {
111
112 line = get_sum_line();
113
114 switch (arpop) {
115 case ARPOP_REQUEST:
116 (void) snprintf(line, MAXLINE, "ARP C Who is %s ?",
117 printip(tip));
118 break;
119 case ARPOP_REPLY:
120 (void) snprintf(line, MAXLINE, "ARP R %s is %s",
121 printip(sip), smacbuf);
122 dst_name = addrtoname_align(tip);
123 break;
124 case REVARP_REQUEST:
125 (void) snprintf(line, MAXLINE, "RARP C Who is %s ?",
126 dmacbuf);
127 break;
128 case REVARP_REPLY:
129 (void) snprintf(line, MAXLINE, "RARP R %s is %s",
130 dmacbuf, printip(tip));
131 dst_name = addrtoname_align(tip);
132 break;
133 }
134 }
135
136 if (flags & F_DTAIL) {
137 show_header("ARP: ", "ARP/RARP Frame", alen);
138 show_space();
139 (void) snprintf(get_line(0, 0), get_line_remain(),
140 "Hardware type = %d (%s)", ntohs(ap->ar_hrd),
141 arp_htype(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
211 /*
212 * These numbers are assigned by the IANA. See the arp-parameters registry.
213 * Only those values that are used within Solaris have #defines.
214 */
215 const char *
216 arp_htype(int t)
217 {
218 switch (t) {
219 case ARPHRD_ETHER:
220 return ("Ethernet (10Mb)");
221 case 2:
222 return ("Experimental Ethernet (3MB)");
223 case 3:
224 return ("Amateur Radio AX.25");
225 case 4:
226 return ("Proteon ProNET Token Ring");
227 case 5:
228 return ("Chaos");
229 case ARPHRD_IEEE802:
230 return ("IEEE 802");
231 case 7:
232 return ("ARCNET");
233 case 8:
234 return ("Hyperchannel");
235 case 9:
236 return ("Lanstar");
237 case 10:
238 return ("Autonet");
239 case 11:
240 return ("LocalTalk");
241 case 12:
242 return ("LocalNet");
243 case 13:
244 return ("Ultra Link");
245 case 14:
246 return ("SMDS");
247 case ARPHRD_FRAME:
248 return ("Frame Relay");
249 case ARPHRD_ATM:
250 return ("ATM");
251 case ARPHRD_HDLC:
252 return ("HDLC");
253 case ARPHRD_FC:
254 return ("Fibre Channel");
255 case ARPHRD_IPATM:
256 return ("IP-ATM");
257 case ARPHRD_TUNNEL:
258 return ("Tunnel");
259 case ARPHRD_IB:
260 return ("IPIB");
261 };
262 return ("UNKNOWN");
263 }