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 <sys/socket.h>
30 #include <net/if.h>
31 #include <net/if_arp.h>
32 #include <netinet/in_systm.h>
33 #include <netinet/in.h>
34 #include <netinet/ip.h>
35 #include <netinet/if_ether.h>
36 #include <netdb.h>
37 #include <net/if_types.h>
38
39 #include "snoop.h"
40
41 extern char *dlc_header;
42 extern jmp_buf xdr_err;
43
44 static char *printip(unsigned char *);
45 static char *addrtoname_align(unsigned char *);
46
47 static char unarp_addr[] = "Unknown";
48 char *opname[] = {
49 "",
50 "ARP Request",
51 "ARP Reply",
52 "REVARP Request",
53 "REVARP Reply",
54 };
55
56 void
interpret_arp(int flags,struct arphdr * ap,int alen)57 interpret_arp(int flags, struct arphdr *ap, int alen)
58 {
59 char *line;
60 extern char *src_name, *dst_name;
61 unsigned char *sip, *tip, *sha, *tha;
62 char *smacbuf = NULL, *dmacbuf = NULL;
63 int maclen;
64 ushort_t arpop;
65 boolean_t is_ip = B_FALSE;
66
67 /*
68 * Check that at least the generic ARP header was received.
69 */
70 if (sizeof (struct arphdr) > alen)
71 goto short_packet;
72
73 arpop = ntohs(ap->ar_op);
74 maclen = ap->ar_hln;
75 if (ntohs(ap->ar_pro) == ETHERTYPE_IP)
76 is_ip = B_TRUE;
77
78 sha = (unsigned char *)(ap + 1);
79 sip = sha + maclen;
80 tha = sip + ap->ar_pln;
81 tip = tha + maclen;
82
83 /*
84 * Check that the protocol/hardware addresses were received.
85 */
86 if ((tip + ap->ar_pln) > ((unsigned char *)ap + alen))
87 goto short_packet;
88
89 if (maclen == 0) {
90 smacbuf = dmacbuf = unarp_addr;
91 } else {
92 if (((flags & F_DTAIL) && is_ip) || (arpop == ARPOP_REPLY)) {
93 smacbuf = _link_ntoa(sha, NULL, maclen, IFT_OTHER);
94 if (smacbuf == NULL)
95 pr_err("Warning: malloc failure");
96 }
97
98 if (((flags & F_DTAIL) && is_ip) || (arpop ==
99 REVARP_REQUEST) || (arpop == REVARP_REPLY)) {
100 dmacbuf = _link_ntoa(tha, NULL, maclen, IFT_OTHER);
101 if (dmacbuf == NULL)
102 pr_err("Warning: malloc failure");
103 }
104 }
105
106 src_name = addrtoname_align(sip);
107
108 if (flags & F_SUM) {
109
110 line = get_sum_line();
111
112 switch (arpop) {
113 case ARPOP_REQUEST:
114 (void) snprintf(line, MAXLINE, "ARP C Who is %s ?",
115 printip(tip));
116 break;
117 case ARPOP_REPLY:
118 (void) snprintf(line, MAXLINE, "ARP R %s is %s",
119 printip(sip), smacbuf);
120 dst_name = addrtoname_align(tip);
121 break;
122 case REVARP_REQUEST:
123 (void) snprintf(line, MAXLINE, "RARP C Who is %s ?",
124 dmacbuf);
125 break;
126 case REVARP_REPLY:
127 (void) snprintf(line, MAXLINE, "RARP R %s is %s",
128 dmacbuf, printip(tip));
129 dst_name = addrtoname_align(tip);
130 break;
131 }
132 }
133
134 if (flags & F_DTAIL) {
135 show_header("ARP: ", "ARP/RARP Frame", alen);
136 show_space();
137 (void) snprintf(get_line(0, 0), get_line_remain(),
138 "Hardware type = %d (%s)", ntohs(ap->ar_hrd),
139 arp_htype(ntohs(ap->ar_hrd)));
140 (void) snprintf(get_line(0, 0), get_line_remain(),
141 "Protocol type = %04x (%s)", ntohs(ap->ar_pro),
142 print_ethertype(ntohs(ap->ar_pro)));
143 (void) snprintf(get_line(0, 0), get_line_remain(),
144 "Length of hardware address = %d bytes", ap->ar_hln);
145 (void) snprintf(get_line(0, 0), get_line_remain(),
146 "Length of protocol address = %d bytes", ap->ar_pln);
147 (void) snprintf(get_line(0, 0), get_line_remain(),
148 "Opcode %d (%s)", arpop,
149 (arpop > REVARP_REPLY) ? opname[0] : opname[arpop]);
150
151 if (is_ip) {
152 (void) snprintf(get_line(0, 0), get_line_remain(),
153 "Sender's hardware address = %s", smacbuf);
154 (void) snprintf(get_line(0, 0), get_line_remain(),
155 "Sender's protocol address = %s",
156 printip(sip));
157 (void) snprintf(get_line(0, 0), get_line_remain(),
158 "Target hardware address = %s",
159 arpop == ARPOP_REQUEST ? "?" : dmacbuf);
160 (void) snprintf(get_line(0, 0), get_line_remain(),
161 "Target protocol address = %s",
162 arpop == REVARP_REQUEST ? "?" :
163 printip(tip));
164 }
165 show_trailer();
166 }
167
168 if (maclen != 0) {
169 free(smacbuf);
170 free(dmacbuf);
171 }
172 return;
173
174 short_packet:
175 if (flags & F_SUM) {
176 (void) snprintf(get_sum_line(), MAXLINE,
177 "ARP (short packet)");
178 } else if (flags & F_DTAIL) {
179 show_header("ARP: ", "ARP/RARP Frame", alen);
180 show_space();
181 (void) snprintf(get_line(0, 0), get_line_remain(),
182 "ARP (short packet)");
183 }
184 }
185
186 char *
printip(unsigned char * p)187 printip(unsigned char *p)
188 {
189 static char buff[MAXHOSTNAMELEN + 32];
190 char *ap, *np;
191 struct in_addr a;
192
193 memcpy(&a, p, 4);
194 ap = (char *)inet_ntoa(a);
195 np = (char *)addrtoname(AF_INET, &a);
196 (void) snprintf(buff, MAXHOSTNAMELEN, "%s, %s", ap, np);
197 return (buff);
198 }
199
200 char *
addrtoname_align(unsigned char * p)201 addrtoname_align(unsigned char *p)
202 {
203 struct in_addr a;
204
205 memcpy(&a, p, 4);
206 return ((char *)addrtoname(AF_INET, &a));
207 }
208
209 /*
210 * These numbers are assigned by the IANA. See the arp-parameters registry.
211 * Only those values that are used within Solaris have #defines.
212 */
213 const char *
arp_htype(int t)214 arp_htype(int t)
215 {
216 switch (t) {
217 case ARPHRD_ETHER:
218 return ("Ethernet (10Mb)");
219 case 2:
220 return ("Experimental Ethernet (3MB)");
221 case 3:
222 return ("Amateur Radio AX.25");
223 case 4:
224 return ("Proteon ProNET Token Ring");
225 case 5:
226 return ("Chaos");
227 case ARPHRD_IEEE802:
228 return ("IEEE 802");
229 case 7:
230 return ("ARCNET");
231 case 8:
232 return ("Hyperchannel");
233 case 9:
234 return ("Lanstar");
235 case 10:
236 return ("Autonet");
237 case 11:
238 return ("LocalTalk");
239 case 12:
240 return ("LocalNet");
241 case 13:
242 return ("Ultra Link");
243 case 14:
244 return ("SMDS");
245 case ARPHRD_FRAME:
246 return ("Frame Relay");
247 case ARPHRD_ATM:
248 return ("ATM");
249 case ARPHRD_HDLC:
250 return ("HDLC");
251 case ARPHRD_FC:
252 return ("Fibre Channel");
253 case ARPHRD_IPATM:
254 return ("IP-ATM");
255 case ARPHRD_TUNNEL:
256 return ("Tunnel");
257 case ARPHRD_IB:
258 return ("IPIB");
259 };
260 return ("UNKNOWN");
261 }
262