2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996
3 * The Regents of the University of California. All rights reserved.
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)
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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
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.
22 static const char rcsid[] _U_ =
23 "@(#) $Header: /tcpdump/master/libpcap/pcap-nit.c,v 1.58.2.4 2008-04-14 20:41:52 guy Exp $ (LBL)";
30 #include <sys/types.h>
32 #include <sys/timeb.h>
34 #include <sys/ioctl.h>
35 #include <sys/socket.h>
40 #include <netinet/in.h>
41 #include <netinet/in_systm.h>
42 #include <netinet/ip.h>
43 #include <netinet/if_ether.h>
44 #include <netinet/ip_var.h>
45 #include <netinet/udp.h>
46 #include <netinet/udp_var.h>
47 #include <netinet/tcp.h>
48 #include <netinet/tcpip.h>
56 #ifdef HAVE_OS_PROTO_H
61 * The chunk size for NIT. This is the amount of buffering
62 * done for read calls.
64 #define CHUNKSIZE (2*1024)
67 * The total buffer space used by NIT.
69 #define BUFSPACE (4*CHUNKSIZE)
72 static int nit_setflags(int, int, int, char *);
75 pcap_stats_nit(pcap_t *p, struct pcap_stat *ps)
79 * "ps_recv" counts packets handed to the filter, not packets
80 * that passed the filter. As filtering is done in userland,
81 * this does not include packets dropped because we ran out
84 * "ps_drop" presumably counts packets dropped by the socket
85 * because of flow control requirements or resource exhaustion;
86 * it doesn't count packets dropped by the interface driver.
87 * As filtering is done in userland, it counts packets regardless
88 * of whether they would've passed the filter.
90 * These statistics don't include packets not yet read from the
91 * kernel by libpcap or packets not yet read from libpcap by the
99 pcap_read_nit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
102 register u_char *bp, *cp, *ep;
103 register struct nit_hdr *nh;
108 cc = read(p->fd, (char *)p->buffer, p->bufsize);
110 if (errno == EWOULDBLOCK)
112 snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
113 pcap_strerror(errno));
121 * Loop through each packet. The increment expression
122 * rounds up to the next int boundary past the end of
123 * the previous packet.
129 * Has "pcap_breakloop()" been called?
130 * If so, return immediately - if we haven't read any
131 * packets, clear the flag and return -2 to indicate
132 * that we were told to break out of the loop, otherwise
133 * leave the flag set, so that the *next* call will break
134 * out of the loop without having read any packets, and
135 * return the number of packets we've processed so far.
148 nh = (struct nit_hdr *)bp;
149 cp = bp + sizeof(*nh);
151 switch (nh->nh_state) {
159 p->md.stat.ps_drop = nh->nh_dropped;
166 snprintf(p->errbuf, sizeof(p->errbuf),
167 "bad nit state %d", nh->nh_state);
170 ++p->md.stat.ps_recv;
171 bp += ((sizeof(struct nit_hdr) + nh->nh_datalen +
172 sizeof(int) - 1) & ~(sizeof(int) - 1));
174 caplen = nh->nh_wirelen;
175 if (caplen > p->snapshot)
176 caplen = p->snapshot;
177 if (bpf_filter(p->fcode.bf_insns, cp, nh->nh_wirelen, caplen)) {
178 struct pcap_pkthdr h;
179 h.ts = nh->nh_timestamp;
180 h.len = nh->nh_wirelen;
182 (*callback)(user, &h, cp);
183 if (++n >= cnt && cnt > 0) {
195 pcap_inject_nit(pcap_t *p, const void *buf, size_t size)
200 memset(&sa, 0, sizeof(sa));
201 strncpy(sa.sa_data, device, sizeof(sa.sa_data));
202 ret = sendto(p->fd, buf, size, 0, &sa, sizeof(sa));
204 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s",
205 pcap_strerror(errno));
212 nit_setflags(int fd, int promisc, int to_ms, char *ebuf)
216 memset(&nioc, 0, sizeof(nioc));
217 nioc.nioc_bufspace = BUFSPACE;
218 nioc.nioc_chunksize = CHUNKSIZE;
219 nioc.nioc_typetomatch = NT_ALLTYPES;
220 nioc.nioc_snaplen = p->snapshot;
221 nioc.nioc_bufalign = sizeof(int);
222 nioc.nioc_bufoffset = 0;
225 nioc.nioc_flags |= NF_TIMEOUT;
226 nioc.nioc_timeout.tv_sec = to_ms / 1000;
227 nioc.nioc_timeout.tv_usec = (to_ms * 1000) % 1000000;
230 nioc.nioc_flags |= NF_PROMISC;
232 if (ioctl(fd, SIOCSNIT, &nioc) < 0) {
233 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s",
234 pcap_strerror(errno));
241 pcap_activate_nit(pcap_t *p)
244 struct sockaddr_nit snit;
248 * No monitor mode on SunOS 3.x or earlier (no
249 * Wi-Fi *devices* for the hardware that supported
252 return (PCAP_ERROR_RFMON_NOTSUP);
255 if (p->snapshot < 96)
257 * NIT requires a snapshot length of at least 96.
261 memset(p, 0, sizeof(*p));
262 p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW);
264 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
265 "socket: %s", pcap_strerror(errno));
268 snit.snit_family = AF_NIT;
269 (void)strncpy(snit.snit_ifname, p->opt.source, NITIFSIZ);
271 if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) {
272 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
273 "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno));
276 nit_setflags(p->fd, p->opt.promisc, p->md.timeout, p->errbuf);
279 * NIT supports only ethernets.
281 p->linktype = DLT_EN10MB;
283 p->bufsize = BUFSPACE;
284 p->buffer = (u_char *)malloc(p->bufsize);
285 if (p->buffer == NULL) {
286 strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
291 * "p->fd" is a socket, so "select()" should work on it.
293 p->selectable_fd = p->fd;
296 * This is (presumably) a real Ethernet capture; give it a
297 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
298 * that an application can let you choose it, in case you're
299 * capturing DOCSIS traffic that a Cisco Cable Modem
300 * Termination System is putting out onto an Ethernet (it
301 * doesn't put an Ethernet header onto the wire, it puts raw
302 * DOCSIS frames out on the wire inside the low-level
305 p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
307 * If that fails, just leave the list empty.
309 if (p->dlt_list != NULL) {
310 p->dlt_list[0] = DLT_EN10MB;
311 p->dlt_list[1] = DLT_DOCSIS;
315 p->read_op = pcap_read_nit;
316 p->inject_op = pcap_inject_nit;
317 p->setfilter_op = install_bpf_program; /* no kernel filtering */
318 p->setdirection_op = NULL; /* Not implemented. */
319 p->set_datalink_op = NULL; /* can't change data link type */
320 p->getnonblock_op = pcap_getnonblock_fd;
321 p->setnonblock_op = pcap_setnonblock_fd;
322 p->stats_op = pcap_stats_nit;
330 pcap_create(const char *device, char *ebuf)
334 p = pcap_create_common(device, ebuf);
338 p->activate_op = pcap_activate_nit;
343 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)