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)
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
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[] =
23 "@(#) $Header: /tcpdump/master/libpcap/pcap-nit.c,v 1.41 2001/12/10 07:14:18 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(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(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
102 register struct bpf_insn *fcode = p->fcode.bf_insns;
103 register u_char *bp, *cp, *ep;
104 register struct nit_hdr *nh;
109 cc = read(p->fd, (char *)p->buffer, p->bufsize);
111 if (errno == EWOULDBLOCK)
113 snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
114 pcap_strerror(errno));
122 * Loop through each packet. The increment expression
123 * rounds up to the next int boundary past the end of
124 * the previous packet.
129 nh = (struct nit_hdr *)bp;
130 cp = bp + sizeof(*nh);
132 switch (nh->nh_state) {
140 p->md.stat.ps_drop = nh->nh_dropped;
147 snprintf(p->errbuf, sizeof(p->errbuf),
148 "bad nit state %d", nh->nh_state);
151 ++p->md.stat.ps_recv;
152 bp += ((sizeof(struct nit_hdr) + nh->nh_datalen +
153 sizeof(int) - 1) & ~(sizeof(int) - 1));
155 caplen = nh->nh_wirelen;
156 if (caplen > p->snapshot)
157 caplen = p->snapshot;
158 if (bpf_filter(fcode, cp, nh->nh_wirelen, caplen)) {
159 struct pcap_pkthdr h;
160 h.ts = nh->nh_timestamp;
161 h.len = nh->nh_wirelen;
163 (*callback)(user, &h, cp);
164 if (++n >= cnt && cnt >= 0) {
176 nit_setflags(int fd, int promisc, int to_ms, char *ebuf)
180 memset(&nioc, 0, sizeof(nioc));
181 nioc.nioc_bufspace = BUFSPACE;
182 nioc.nioc_chunksize = CHUNKSIZE;
183 nioc.nioc_typetomatch = NT_ALLTYPES;
184 nioc.nioc_snaplen = p->snapshot;
185 nioc.nioc_bufalign = sizeof(int);
186 nioc.nioc_bufoffset = 0;
189 nioc.nioc_flags |= NF_TIMEOUT;
190 nioc.nioc_timeout.tv_sec = to_ms / 1000;
191 nioc.nioc_timeout.tv_usec = (to_ms * 1000) % 1000000;
194 nioc.nioc_flags |= NF_PROMISC;
196 if (ioctl(fd, SIOCSNIT, &nioc) < 0) {
197 snprintf(ebuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s",
198 pcap_strerror(errno));
205 pcap_open_live(char *device, int snaplen, int promisc, int to_ms, char *ebuf)
208 struct sockaddr_nit snit;
211 p = (pcap_t *)malloc(sizeof(*p));
213 strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
219 * NIT requires a snapshot length of at least 96.
223 memset(p, 0, sizeof(*p));
224 p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW);
226 snprintf(ebuf, PCAP_ERRBUF_SIZE,
227 "socket: %s", pcap_strerror(errno));
230 snit.snit_family = AF_NIT;
231 (void)strncpy(snit.snit_ifname, device, NITIFSIZ);
233 if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) {
234 snprintf(ebuf, PCAP_ERRBUF_SIZE,
235 "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno));
238 p->snapshot = snaplen;
239 nit_setflags(p->fd, promisc, to_ms, ebuf);
242 * NIT supports only ethernets.
244 p->linktype = DLT_EN10MB;
246 p->bufsize = BUFSPACE;
247 p->buffer = (u_char *)malloc(p->bufsize);
248 if (p->buffer == NULL) {
249 strlcpy(ebuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
261 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
264 if (install_bpf_program(p, fp) < 0)