1 /*-
2 * Copyright (c) 2001, 2002, 2004 Lev Walkin <vlm@lionet.info>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $Id: loop-bpf.c,v 1.15 2007/04/22 07:22:40 vlm Exp $
27 */
28
29 #include "ipcad.h"
30 #include "opt.h"
31
32 #define bpf_header ((struct bpf_hdr *)packet)
33
34
35 /*
36 * This is the interface loop - a busy horse handling interface statistics.
37 */
38 void *
process_bpf(void * psp)39 process_bpf(void *psp) {
40 packet_source_t *ps = psp;
41 ssize_t rd;
42 char *packet, *safe_end;
43 struct pollfd pfd;
44
45 assert(ps->iface_type == IFACE_BPF);
46
47 pfd.fd = ps->fd;
48 pfd.events = POLLIN;
49
50 for(rd = 0;;) {
51
52 if(signoff_now)
53 break;
54
55 if(rd == -1) {
56 if(errno != EAGAIN) {
57 ps->fd = -1;
58 close(pfd.fd);
59 pfd.fd = -1;
60 }
61 }
62
63 if(ps->state != PST_READY || ps->fd == -1) {
64 if(init_packet_source(ps, 1)) {
65 sleep(5);
66 continue;
67 }
68 assert(ps->state == PST_READY);
69 fprintf(stderr, "\n");
70 pfd.fd = ps->fd;
71 }
72
73 rd = poll(&pfd, 1, 3000);
74
75 /* Poll timeout is almost impossible thing */
76 if(rd == 0)
77 continue;
78
79 if((rd == -1) || !(pfd.revents & POLLIN)) {
80 if(rd > 0 && pfd.revents & POLLNVAL) {
81 fprintf(stderr,
82 "[%s: INVALID INTERFACE! (%d/%d/%d)]\n",
83 ps->ifName, (int)rd, pfd.fd, pfd.revents);
84 sleep(1);
85 }
86 rd = -1;
87 continue;
88 }
89
90 if(signoff_now)
91 break;
92
93 rd = read(ps->fd, ps->buf, ps->bufsize);
94
95 /*
96 * Processing packets
97 */
98 for(packet = ps->buf,
99 safe_end = packet + rd - sizeof(struct bpf_hdr);
100 packet < safe_end;
101 packet += BPF_WORDALIGN(bpf_header->bh_hdrlen
102 + bpf_header->bh_caplen) )
103 {
104 void *ip_start = packet + bpf_header->bh_hdrlen;
105 int toend_size = rd-((char *)ip_start-(char *)ps->buf);
106 int captured_size = bpf_header->bh_caplen;
107 if(toend_size < captured_size) /* Paranoya */
108 captured_size = toend_size;
109 process_packet_data(ps, ip_start, captured_size, 0, 0);
110 }
111
112 }
113
114 return 0;
115
116 }
117
118