1 /*
2 * Copyright (c) 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 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25
26 #include <sys/types.h>
27 #include <sys/time.h>
28 #include <sys/timeb.h>
29 #include <sys/file.h>
30 #include <sys/ioctl.h>
31 #include <sys/socket.h>
32
33 #include <net/if.h>
34 #include <net/nit.h>
35
36 #include <netinet/in.h>
37 #include <netinet/in_systm.h>
38 #include <netinet/ip.h>
39 #include <netinet/if_ether.h>
40 #include <netinet/ip_var.h>
41 #include <netinet/udp.h>
42 #include <netinet/udp_var.h>
43 #include <netinet/tcp.h>
44 #include <netinet/tcpip.h>
45
46 #include <ctype.h>
47 #include <errno.h>
48 #include <stdio.h>
49
50 #include "pcap-int.h"
51
52 #ifdef HAVE_OS_PROTO_H
53 #include "os-proto.h"
54 #endif
55
56 /*
57 * The chunk size for NIT. This is the amount of buffering
58 * done for read calls.
59 */
60 #define CHUNKSIZE (2*1024)
61
62 /*
63 * The total buffer space used by NIT.
64 */
65 #define BUFSPACE (4*CHUNKSIZE)
66
67 /* Forwards */
68 static int nit_setflags(int, int, int, char *);
69
70 /*
71 * Private data for capturing on NIT devices.
72 */
73 struct pcap_nit {
74 struct pcap_stat stat;
75 };
76
77 static int
pcap_stats_nit(pcap_t * p,struct pcap_stat * ps)78 pcap_stats_nit(pcap_t *p, struct pcap_stat *ps)
79 {
80 struct pcap_nit *pn = p->priv;
81
82 /*
83 * "ps_recv" counts packets handed to the filter, not packets
84 * that passed the filter. As filtering is done in userland,
85 * this does not include packets dropped because we ran out
86 * of buffer space.
87 *
88 * "ps_drop" presumably counts packets dropped by the socket
89 * because of flow control requirements or resource exhaustion;
90 * it doesn't count packets dropped by the interface driver.
91 * As filtering is done in userland, it counts packets regardless
92 * of whether they would've passed the filter.
93 *
94 * These statistics don't include packets not yet read from the
95 * kernel by libpcap or packets not yet read from libpcap by the
96 * application.
97 */
98 *ps = pn->stat;
99 return (0);
100 }
101
102 static int
pcap_read_nit(pcap_t * p,int cnt,pcap_handler callback,u_char * user)103 pcap_read_nit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
104 {
105 struct pcap_nit *pn = p->priv;
106 register int cc, n;
107 register u_char *bp, *cp, *ep;
108 register struct nit_hdr *nh;
109 register int caplen;
110
111 cc = p->cc;
112 if (cc == 0) {
113 cc = read(p->fd, (char *)p->buffer, p->bufsize);
114 if (cc < 0) {
115 if (errno == EWOULDBLOCK)
116 return (0);
117 pcap_snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
118 pcap_strerror(errno));
119 return (-1);
120 }
121 bp = (u_char *)p->buffer;
122 } else
123 bp = p->bp;
124
125 /*
126 * Loop through each packet. The increment expression
127 * rounds up to the next int boundary past the end of
128 * the previous packet.
129 */
130 n = 0;
131 ep = bp + cc;
132 while (bp < ep) {
133 /*
134 * Has "pcap_breakloop()" been called?
135 * If so, return immediately - if we haven't read any
136 * packets, clear the flag and return -2 to indicate
137 * that we were told to break out of the loop, otherwise
138 * leave the flag set, so that the *next* call will break
139 * out of the loop without having read any packets, and
140 * return the number of packets we've processed so far.
141 */
142 if (p->break_loop) {
143 if (n == 0) {
144 p->break_loop = 0;
145 return (-2);
146 } else {
147 p->cc = ep - bp;
148 p->bp = bp;
149 return (n);
150 }
151 }
152
153 nh = (struct nit_hdr *)bp;
154 cp = bp + sizeof(*nh);
155
156 switch (nh->nh_state) {
157
158 case NIT_CATCH:
159 break;
160
161 case NIT_NOMBUF:
162 case NIT_NOCLUSTER:
163 case NIT_NOSPACE:
164 pn->stat.ps_drop = nh->nh_dropped;
165 continue;
166
167 case NIT_SEQNO:
168 continue;
169
170 default:
171 pcap_snprintf(p->errbuf, sizeof(p->errbuf),
172 "bad nit state %d", nh->nh_state);
173 return (-1);
174 }
175 ++pn->stat.ps_recv;
176 bp += ((sizeof(struct nit_hdr) + nh->nh_datalen +
177 sizeof(int) - 1) & ~(sizeof(int) - 1));
178
179 caplen = nh->nh_wirelen;
180 if (caplen > p->snapshot)
181 caplen = p->snapshot;
182 if (bpf_filter(p->fcode.bf_insns, cp, nh->nh_wirelen, caplen)) {
183 struct pcap_pkthdr h;
184 h.ts = nh->nh_timestamp;
185 h.len = nh->nh_wirelen;
186 h.caplen = caplen;
187 (*callback)(user, &h, cp);
188 if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
189 p->cc = ep - bp;
190 p->bp = bp;
191 return (n);
192 }
193 }
194 }
195 p->cc = 0;
196 return (n);
197 }
198
199 static int
pcap_inject_nit(pcap_t * p,const void * buf,size_t size)200 pcap_inject_nit(pcap_t *p, const void *buf, size_t size)
201 {
202 struct sockaddr sa;
203 int ret;
204
205 memset(&sa, 0, sizeof(sa));
206 strncpy(sa.sa_data, device, sizeof(sa.sa_data));
207 ret = sendto(p->fd, buf, size, 0, &sa, sizeof(sa));
208 if (ret == -1) {
209 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s",
210 pcap_strerror(errno));
211 return (-1);
212 }
213 return (ret);
214 }
215
216 static int
nit_setflags(pcap_t * p)217 nit_setflags(pcap_t *p)
218 {
219 struct nit_ioc nioc;
220
221 memset(&nioc, 0, sizeof(nioc));
222 nioc.nioc_typetomatch = NT_ALLTYPES;
223 nioc.nioc_snaplen = p->snapshot;
224 nioc.nioc_bufalign = sizeof(int);
225 nioc.nioc_bufoffset = 0;
226
227 if (p->opt.buffer_size != 0)
228 nioc.nioc_bufspace = p->opt.buffer_size;
229 else {
230 /* Default buffer size */
231 nioc.nioc_bufspace = BUFSPACE;
232 }
233
234 if (p->opt.immediate) {
235 /*
236 * XXX - will this cause packets to be delivered immediately?
237 * XXX - given that this is for SunOS prior to 4.0, do
238 * we care?
239 */
240 nioc.nioc_chunksize = 0;
241 } else
242 nioc.nioc_chunksize = CHUNKSIZE;
243 if (p->opt.timeout != 0) {
244 nioc.nioc_flags |= NF_TIMEOUT;
245 nioc.nioc_timeout.tv_sec = p->opt.timeout / 1000;
246 nioc.nioc_timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;
247 }
248 if (p->opt.promisc)
249 nioc.nioc_flags |= NF_PROMISC;
250
251 if (ioctl(p->fd, SIOCSNIT, &nioc) < 0) {
252 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s",
253 pcap_strerror(errno));
254 return (-1);
255 }
256 return (0);
257 }
258
259 static int
pcap_activate_nit(pcap_t * p)260 pcap_activate_nit(pcap_t *p)
261 {
262 int fd;
263 struct sockaddr_nit snit;
264
265 if (p->opt.rfmon) {
266 /*
267 * No monitor mode on SunOS 3.x or earlier (no
268 * Wi-Fi *devices* for the hardware that supported
269 * them!).
270 */
271 return (PCAP_ERROR_RFMON_NOTSUP);
272 }
273
274 if (p->snapshot < 96)
275 /*
276 * NIT requires a snapshot length of at least 96.
277 */
278 p->snapshot = 96;
279
280 memset(p, 0, sizeof(*p));
281 p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW);
282 if (fd < 0) {
283 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
284 "socket: %s", pcap_strerror(errno));
285 goto bad;
286 }
287 snit.snit_family = AF_NIT;
288 (void)strncpy(snit.snit_ifname, p->opt.device, NITIFSIZ);
289
290 if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) {
291 /*
292 * XXX - there's probably a particular bind error that
293 * means "there's no such device" and a particular bind
294 * error that means "that device doesn't support NIT";
295 * they might be the same error, if they both end up
296 * meaning "NIT doesn't know about that device".
297 */
298 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
299 "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno));
300 goto bad;
301 }
302 if (nit_setflags(p) < 0)
303 goto bad;
304
305 /*
306 * NIT supports only ethernets.
307 */
308 p->linktype = DLT_EN10MB;
309
310 p->bufsize = BUFSPACE;
311 p->buffer = malloc(p->bufsize);
312 if (p->buffer == NULL) {
313 strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
314 goto bad;
315 }
316
317 /*
318 * "p->fd" is a socket, so "select()" should work on it.
319 */
320 p->selectable_fd = p->fd;
321
322 /*
323 * This is (presumably) a real Ethernet capture; give it a
324 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
325 * that an application can let you choose it, in case you're
326 * capturing DOCSIS traffic that a Cisco Cable Modem
327 * Termination System is putting out onto an Ethernet (it
328 * doesn't put an Ethernet header onto the wire, it puts raw
329 * DOCSIS frames out on the wire inside the low-level
330 * Ethernet framing).
331 */
332 p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
333 /*
334 * If that fails, just leave the list empty.
335 */
336 if (p->dlt_list != NULL) {
337 p->dlt_list[0] = DLT_EN10MB;
338 p->dlt_list[1] = DLT_DOCSIS;
339 p->dlt_count = 2;
340 }
341
342 p->read_op = pcap_read_nit;
343 p->inject_op = pcap_inject_nit;
344 p->setfilter_op = install_bpf_program; /* no kernel filtering */
345 p->setdirection_op = NULL; /* Not implemented. */
346 p->set_datalink_op = NULL; /* can't change data link type */
347 p->getnonblock_op = pcap_getnonblock_fd;
348 p->setnonblock_op = pcap_setnonblock_fd;
349 p->stats_op = pcap_stats_nit;
350
351 return (0);
352 bad:
353 pcap_cleanup_live_common(p);
354 return (PCAP_ERROR);
355 }
356
357 pcap_t *
pcap_create_interface(const char * device _U_,char * ebuf)358 pcap_create_interface(const char *device _U_, char *ebuf)
359 {
360 pcap_t *p;
361
362 p = pcap_create_common(ebuf, sizeof (struct pcap_nit));
363 if (p == NULL)
364 return (NULL);
365
366 p->activate_op = pcap_activate_nit;
367 return (p);
368 }
369
370 /*
371 * XXX - there's probably a particular bind error that means "that device
372 * doesn't support NIT"; if so, we should try a bind and use that.
373 */
374 static int
can_be_bound(const char * name _U_)375 can_be_bound(const char *name _U_)
376 {
377 return (1);
378 }
379
380 int
pcap_platform_finddevs(pcap_if_t ** alldevsp,char * errbuf)381 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
382 {
383 return (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound));
384 }
385