nf-queue.c revision f9071054d0f2512dea9e95f99c308e931ed78dba 
1/*
2 * src/nf-log.c     Monitor netfilter queue events
3 *
4 *	This library is free software; you can redistribute it and/or
5 *	modify it under the terms of the GNU Lesser General Public
6 *	License as published by the Free Software Foundation version 2.1
7 *	of the License.
8 *
9 * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
10 */
11
12
13#include "queue-utils.h"
14
15static struct nl_sock *nf_sock;
16
17static void obj_input(struct nl_object *obj, void *arg)
18{
19	struct nfnl_queue_msg *msg = (struct nfnl_queue_msg *) obj;
20	struct nl_dump_params dp = {
21		.dp_type = NL_DUMP_STATS,
22		.dp_fd = stdout,
23		.dp_dump_msgtype = 1,
24	};
25
26	nfnl_queue_msg_set_verdict(msg, NF_ACCEPT);
27	nl_object_dump(obj, &dp);
28	nfnl_queue_msg_send_verdict(nf_sock, msg);
29}
30
31static int event_input(struct nl_msg *msg, void *arg)
32{
33	if (nl_msg_parse(msg, &obj_input, NULL) < 0)
34		fprintf(stderr, "<<EVENT>> Unknown message type\n");
35
36	/* Exit nl_recvmsgs_def() and return to the main select() */
37	return NL_STOP;
38}
39
40int main(int argc, char *argv[])
41{
42	struct nl_sock *rt_sock;
43	struct nl_cache *link_cache;
44	struct nfnl_queue *queue;
45	enum nfnl_queue_copy_mode copy_mode;
46	uint32_t copy_range;
47	int err = 1;
48	int family;
49
50	nf_sock = nfnl_queue_socket_alloc();
51	if (nf_sock == NULL)
52		fatal(ENOBUFS, "Unable to allocate netlink socket");
53
54	nl_socket_disable_seq_check(nf_sock);
55	nl_socket_modify_cb(nf_sock, NL_CB_VALID, NL_CB_CUSTOM, event_input, NULL);
56
57	if ((argc > 1 && !strcasecmp(argv[1], "-h")) || argc < 3) {
58		printf("Usage: nf-queue family group [ copy_mode ] "
59		       "[ copy_range ]\n");
60		return 2;
61	}
62
63	nlt_connect(nf_sock, NETLINK_NETFILTER);
64
65	if ((family = nl_str2af(argv[1])) == AF_UNSPEC)
66		fatal(NLE_INVAL, "Unknown family \"%s\"", argv[1]);
67
68	nfnl_queue_pf_unbind(nf_sock, family);
69	if ((err = nfnl_queue_pf_bind(nf_sock, family)) < 0)
70		fatal(err, "Unable to bind logger: %s", nl_geterror(err));
71
72	queue = nlt_alloc_queue();
73	nfnl_queue_set_group(queue, atoi(argv[2]));
74
75	copy_mode = NFNL_QUEUE_COPY_PACKET;
76	if (argc > 3) {
77		copy_mode = nfnl_queue_str2copy_mode(argv[3]);
78		if (copy_mode < 0)
79			fatal(copy_mode, "Unable to parse copy mode \"%s\": %s",
80			      argv[3], nl_geterror(copy_mode));
81	}
82	nfnl_queue_set_copy_mode(queue, copy_mode);
83
84	copy_range = 0xFFFF;
85	if (argc > 4)
86		copy_range = atoi(argv[4]);
87	nfnl_queue_set_copy_range(queue, copy_range);
88
89	if ((err = nfnl_queue_create(nf_sock, queue)) < 0)
90		fatal(err, "Unable to bind queue: %s", nl_geterror(err));
91
92	rt_sock = nlt_alloc_socket();
93	nlt_connect(rt_sock, NETLINK_ROUTE);
94	link_cache = nlt_alloc_link_cache(rt_sock);
95
96	while (1) {
97		fd_set rfds;
98		int nffd, rtfd, maxfd, retval;
99
100		FD_ZERO(&rfds);
101
102		maxfd = nffd = nl_socket_get_fd(nf_sock);
103		FD_SET(nffd, &rfds);
104
105		rtfd = nl_socket_get_fd(rt_sock);
106		FD_SET(rtfd, &rfds);
107		if (maxfd < rtfd)
108			maxfd = rtfd;
109
110		/* wait for an incoming message on the netlink socket */
111		retval = select(maxfd+1, &rfds, NULL, NULL, NULL);
112
113		if (retval) {
114			if (FD_ISSET(nffd, &rfds))
115				nl_recvmsgs_default(nf_sock);
116			if (FD_ISSET(rtfd, &rfds))
117				nl_recvmsgs_default(rt_sock);
118		}
119	}
120
121	return 0;
122}
123