1 /*
2 * src/nf-queue.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 * Copyright (c) 2010 Karl Hiramoto <karl@hiramoto.org>
11 */
12
13
14 #include <netlink/cli/utils.h>
15 #include <netlink/cli/link.h>
16 #include <netinet/in.h>
17 #include <linux/netfilter.h>
18 #include <linux/netfilter/nfnetlink_queue.h>
19 #include <netlink/netfilter/nfnl.h>
20 #include <netlink/netfilter/queue.h>
21 #include <netlink/netfilter/queue_msg.h>
22
23 static struct nl_sock *nf_sock;
24
alloc_queue(void)25 static struct nfnl_queue *alloc_queue(void)
26 {
27 struct nfnl_queue *queue;
28
29 queue = nfnl_queue_alloc();
30 if (!queue)
31 nl_cli_fatal(ENOMEM, "Unable to allocate queue object");
32
33 return queue;
34 }
35
36
obj_input(struct nl_object * obj,void * arg)37 static void obj_input(struct nl_object *obj, void *arg)
38 {
39 struct nfnl_queue_msg *msg = (struct nfnl_queue_msg *) obj;
40 struct nl_dump_params dp = {
41 .dp_type = NL_DUMP_STATS,
42 .dp_fd = stdout,
43 .dp_dump_msgtype = 1,
44 };
45
46 nfnl_queue_msg_set_verdict(msg, NF_ACCEPT);
47 nl_object_dump(obj, &dp);
48 nfnl_queue_msg_send_verdict(nf_sock, msg);
49 }
50
event_input(struct nl_msg * msg,void * arg)51 static int event_input(struct nl_msg *msg, void *arg)
52 {
53 if (nl_msg_parse(msg, &obj_input, NULL) < 0)
54 fprintf(stderr, "<<EVENT>> Unknown message type\n");
55
56 /* Exit nl_recvmsgs_def() and return to the main select() */
57 return NL_STOP;
58 }
59
main(int argc,char * argv[])60 int main(int argc, char *argv[])
61 {
62 struct nl_sock *rt_sock;
63 struct nl_cache *link_cache;
64 struct nfnl_queue *queue;
65 enum nfnl_queue_copy_mode copy_mode;
66 uint32_t copy_range;
67 int err = 1;
68 int family;
69
70 nf_sock = nfnl_queue_socket_alloc();
71 if (nf_sock == NULL)
72 nl_cli_fatal(ENOBUFS, "Unable to allocate netlink socket");
73
74 nl_socket_disable_seq_check(nf_sock);
75 nl_socket_modify_cb(nf_sock, NL_CB_VALID, NL_CB_CUSTOM, event_input, NULL);
76
77 if ((argc > 1 && !strcasecmp(argv[1], "-h")) || argc < 3) {
78 printf("Usage: nf-queue family group [ copy_mode ] "
79 "[ copy_range ]\n");
80 printf("family: [ inet | inet6 | ... ] \n");
81 printf("group: the --queue-num arg that you gave to iptables\n");
82 printf("copy_mode: [ none | meta | packet ] \n");
83 return 2;
84 }
85
86 nl_cli_connect(nf_sock, NETLINK_NETFILTER);
87
88 if ((family = nl_str2af(argv[1])) == AF_UNSPEC)
89 nl_cli_fatal(NLE_INVAL, "Unknown family \"%s\"", argv[1]);
90
91 nfnl_queue_pf_unbind(nf_sock, family);
92 if ((err = nfnl_queue_pf_bind(nf_sock, family)) < 0)
93 nl_cli_fatal(err, "Unable to bind logger: %s",
94 nl_geterror(err));
95
96 queue = alloc_queue();
97 nfnl_queue_set_group(queue, atoi(argv[2]));
98
99 copy_mode = NFNL_QUEUE_COPY_PACKET;
100 if (argc > 3) {
101 copy_mode = nfnl_queue_str2copy_mode(argv[3]);
102 if (copy_mode < 0)
103 nl_cli_fatal(copy_mode,
104 "Unable to parse copy mode \"%s\": %s",
105 argv[3], nl_geterror(copy_mode));
106 }
107 nfnl_queue_set_copy_mode(queue, copy_mode);
108
109 copy_range = 0xFFFF;
110 if (argc > 4)
111 copy_range = atoi(argv[4]);
112 nfnl_queue_set_copy_range(queue, copy_range);
113
114 if ((err = nfnl_queue_create(nf_sock, queue)) < 0)
115 nl_cli_fatal(err, "Unable to bind queue: %s", nl_geterror(err));
116
117 rt_sock = nl_cli_alloc_socket();
118 nl_cli_connect(rt_sock, NETLINK_ROUTE);
119 link_cache = nl_cli_link_alloc_cache(rt_sock);
120
121 nl_socket_set_buffer_size(nf_sock, 1024*127, 1024*127);
122
123 while (1) {
124 fd_set rfds;
125 int nffd, rtfd, maxfd, retval;
126
127 FD_ZERO(&rfds);
128
129 maxfd = nffd = nl_socket_get_fd(nf_sock);
130 FD_SET(nffd, &rfds);
131
132 rtfd = nl_socket_get_fd(rt_sock);
133 FD_SET(rtfd, &rfds);
134 if (maxfd < rtfd)
135 maxfd = rtfd;
136
137 /* wait for an incoming message on the netlink socket */
138 retval = select(maxfd+1, &rfds, NULL, NULL, NULL);
139
140 if (retval) {
141 if (FD_ISSET(nffd, &rfds))
142 nl_recvmsgs_default(nf_sock);
143 if (FD_ISSET(rtfd, &rfds))
144 nl_recvmsgs_default(rt_sock);
145 }
146 }
147
148 return 0;
149 }
150