1 /*
2 * lib/netfilter/queue_msg.c Netfilter Queue Messages
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 * @ingroup nfnl
15 * @defgroup queue Queue
16 * @brief
17 * @{
18 */
19
20 #include <sys/types.h>
21 #include <linux/netfilter/nfnetlink_queue.h>
22
23 #include <netlink-private/netlink.h>
24 #include <netlink/attr.h>
25 #include <netlink/netfilter/nfnl.h>
26 #include <netlink/netfilter/queue_msg.h>
27 #include <byteswap.h>
28
29 static struct nl_cache_ops nfnl_queue_msg_ops;
30
31 #if __BYTE_ORDER == __BIG_ENDIAN
ntohll(uint64_t x)32 static uint64_t ntohll(uint64_t x)
33 {
34 return x;
35 }
36 #elif __BYTE_ORDER == __LITTLE_ENDIAN
ntohll(uint64_t x)37 static uint64_t ntohll(uint64_t x)
38 {
39 return bswap_64(x);
40 }
41 #endif
42
43 static struct nla_policy queue_policy[NFQA_MAX+1] = {
44 [NFQA_PACKET_HDR] = {
45 .minlen = sizeof(struct nfqnl_msg_packet_hdr),
46 },
47 [NFQA_VERDICT_HDR] = {
48 .minlen = sizeof(struct nfqnl_msg_verdict_hdr),
49 },
50 [NFQA_MARK] = { .type = NLA_U32 },
51 [NFQA_TIMESTAMP] = {
52 .minlen = sizeof(struct nfqnl_msg_packet_timestamp),
53 },
54 [NFQA_IFINDEX_INDEV] = { .type = NLA_U32 },
55 [NFQA_IFINDEX_OUTDEV] = { .type = NLA_U32 },
56 [NFQA_IFINDEX_PHYSINDEV] = { .type = NLA_U32 },
57 [NFQA_IFINDEX_PHYSOUTDEV] = { .type = NLA_U32 },
58 [NFQA_HWADDR] = {
59 .minlen = sizeof(struct nfqnl_msg_packet_hw),
60 },
61 };
62
nfnlmsg_queue_msg_parse(struct nlmsghdr * nlh,struct nfnl_queue_msg ** result)63 int nfnlmsg_queue_msg_parse(struct nlmsghdr *nlh,
64 struct nfnl_queue_msg **result)
65 {
66 struct nfnl_queue_msg *msg;
67 struct nlattr *tb[NFQA_MAX+1];
68 struct nlattr *attr;
69 int err;
70
71 msg = nfnl_queue_msg_alloc();
72 if (!msg)
73 return -NLE_NOMEM;
74
75 msg->ce_msgtype = nlh->nlmsg_type;
76
77 err = nlmsg_parse(nlh, sizeof(struct nfgenmsg), tb, NFQA_MAX,
78 queue_policy);
79 if (err < 0)
80 goto errout;
81
82 nfnl_queue_msg_set_group(msg, nfnlmsg_res_id(nlh));
83 nfnl_queue_msg_set_family(msg, nfnlmsg_family(nlh));
84
85 attr = tb[NFQA_PACKET_HDR];
86 if (attr) {
87 struct nfqnl_msg_packet_hdr *hdr = nla_data(attr);
88
89 nfnl_queue_msg_set_packetid(msg, ntohl(hdr->packet_id));
90 if (hdr->hw_protocol)
91 nfnl_queue_msg_set_hwproto(msg, hdr->hw_protocol);
92 nfnl_queue_msg_set_hook(msg, hdr->hook);
93 }
94
95 attr = tb[NFQA_MARK];
96 if (attr)
97 nfnl_queue_msg_set_mark(msg, ntohl(nla_get_u32(attr)));
98
99 attr = tb[NFQA_TIMESTAMP];
100 if (attr) {
101 struct nfqnl_msg_packet_timestamp *timestamp = nla_data(attr);
102 struct timeval tv;
103
104 tv.tv_sec = ntohll(timestamp->sec);
105 tv.tv_usec = ntohll(timestamp->usec);
106 nfnl_queue_msg_set_timestamp(msg, &tv);
107 }
108
109 attr = tb[NFQA_IFINDEX_INDEV];
110 if (attr)
111 nfnl_queue_msg_set_indev(msg, ntohl(nla_get_u32(attr)));
112
113 attr = tb[NFQA_IFINDEX_OUTDEV];
114 if (attr)
115 nfnl_queue_msg_set_outdev(msg, ntohl(nla_get_u32(attr)));
116
117 attr = tb[NFQA_IFINDEX_PHYSINDEV];
118 if (attr)
119 nfnl_queue_msg_set_physindev(msg, ntohl(nla_get_u32(attr)));
120
121 attr = tb[NFQA_IFINDEX_PHYSOUTDEV];
122 if (attr)
123 nfnl_queue_msg_set_physoutdev(msg, ntohl(nla_get_u32(attr)));
124
125 attr = tb[NFQA_HWADDR];
126 if (attr) {
127 struct nfqnl_msg_packet_hw *hw = nla_data(attr);
128
129 nfnl_queue_msg_set_hwaddr(msg, hw->hw_addr,
130 ntohs(hw->hw_addrlen));
131 }
132
133 attr = tb[NFQA_PAYLOAD];
134 if (attr) {
135 err = nfnl_queue_msg_set_payload(msg, nla_data(attr),
136 nla_len(attr));
137 if (err < 0)
138 goto errout;
139 }
140
141 *result = msg;
142 return 0;
143
144 errout:
145 nfnl_queue_msg_put(msg);
146 return err;
147 }
148
queue_msg_parser(struct nl_cache_ops * ops,struct sockaddr_nl * who,struct nlmsghdr * nlh,struct nl_parser_param * pp)149 static int queue_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
150 struct nlmsghdr *nlh, struct nl_parser_param *pp)
151 {
152 struct nfnl_queue_msg *msg;
153 int err;
154
155 if ((err = nfnlmsg_queue_msg_parse(nlh, &msg)) < 0)
156 return err;
157
158 err = pp->pp_cb((struct nl_object *) msg, pp);
159 nfnl_queue_msg_put(msg);
160 return err;
161 }
162
163 /** @} */
164
165 static struct nl_msg *
__nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg * msg,uint8_t type)166 __nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg,
167 uint8_t type)
168 {
169 struct nl_msg *nlmsg;
170 struct nfqnl_msg_verdict_hdr verdict;
171
172 nlmsg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, type, 0,
173 nfnl_queue_msg_get_family(msg),
174 nfnl_queue_msg_get_group(msg));
175 if (nlmsg == NULL)
176 return NULL;
177
178 verdict.id = htonl(nfnl_queue_msg_get_packetid(msg));
179 verdict.verdict = htonl(nfnl_queue_msg_get_verdict(msg));
180 if (nla_put(nlmsg, NFQA_VERDICT_HDR, sizeof(verdict), &verdict) < 0)
181 goto nla_put_failure;
182
183 if (nfnl_queue_msg_test_mark(msg) &&
184 nla_put_u32(nlmsg, NFQA_MARK,
185 ntohl(nfnl_queue_msg_get_mark(msg))) < 0)
186 goto nla_put_failure;
187
188 return nlmsg;
189
190 nla_put_failure:
191 nlmsg_free(nlmsg);
192 return NULL;
193 }
194
195 struct nl_msg *
nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg * msg)196 nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg)
197 {
198 return __nfnl_queue_msg_build_verdict(msg, NFQNL_MSG_VERDICT);
199 }
200
201 struct nl_msg *
nfnl_queue_msg_build_verdict_batch(const struct nfnl_queue_msg * msg)202 nfnl_queue_msg_build_verdict_batch(const struct nfnl_queue_msg *msg)
203 {
204 return __nfnl_queue_msg_build_verdict(msg, NFQNL_MSG_VERDICT_BATCH);
205 }
206
207 /**
208 * Send a message verdict/mark
209 * @arg nlh netlink messsage header
210 * @arg msg queue msg
211 * @return 0 on OK or error code
212 */
nfnl_queue_msg_send_verdict(struct nl_sock * nlh,const struct nfnl_queue_msg * msg)213 int nfnl_queue_msg_send_verdict(struct nl_sock *nlh,
214 const struct nfnl_queue_msg *msg)
215 {
216 struct nl_msg *nlmsg;
217 int err;
218
219 nlmsg = nfnl_queue_msg_build_verdict(msg);
220 if (nlmsg == NULL)
221 return -NLE_NOMEM;
222
223 err = nl_send_auto_complete(nlh, nlmsg);
224 nlmsg_free(nlmsg);
225 if (err < 0)
226 return err;
227 return wait_for_ack(nlh);
228 }
229
230 /**
231 * Send a message batched verdict/mark
232 * @arg nlh netlink messsage header
233 * @arg msg queue msg
234 * @return 0 on OK or error code
235 */
nfnl_queue_msg_send_verdict_batch(struct nl_sock * nlh,const struct nfnl_queue_msg * msg)236 int nfnl_queue_msg_send_verdict_batch(struct nl_sock *nlh,
237 const struct nfnl_queue_msg *msg)
238 {
239 struct nl_msg *nlmsg;
240 int err;
241
242 nlmsg = nfnl_queue_msg_build_verdict_batch(msg);
243 if (nlmsg == NULL)
244 return -NLE_NOMEM;
245
246 err = nl_send_auto_complete(nlh, nlmsg);
247 nlmsg_free(nlmsg);
248 if (err < 0)
249 return err;
250 return wait_for_ack(nlh);
251 }
252
253 /**
254 * Send a message verdict including the payload
255 * @arg nlh netlink messsage header
256 * @arg msg queue msg
257 * @arg payload_data packet payload data
258 * @arg payload_len payload length
259 * @return 0 on OK or error code
260 */
nfnl_queue_msg_send_verdict_payload(struct nl_sock * nlh,const struct nfnl_queue_msg * msg,const void * payload_data,unsigned payload_len)261 int nfnl_queue_msg_send_verdict_payload(struct nl_sock *nlh,
262 const struct nfnl_queue_msg *msg,
263 const void *payload_data, unsigned payload_len)
264 {
265 struct nl_msg *nlmsg;
266 int err;
267 struct iovec iov[3];
268 struct nlattr nla;
269
270 nlmsg = nfnl_queue_msg_build_verdict(msg);
271 if (nlmsg == NULL)
272 return -NLE_NOMEM;
273
274 memset(iov, 0, sizeof(iov));
275
276 iov[0].iov_base = (void *) nlmsg_hdr(nlmsg);
277 iov[0].iov_len = nlmsg_hdr(nlmsg)->nlmsg_len;
278
279 nla.nla_type = NFQA_PAYLOAD;
280 nla.nla_len = payload_len + sizeof(nla);
281 nlmsg_hdr(nlmsg)->nlmsg_len += nla.nla_len;
282
283 iov[1].iov_base = (void *) &nla;
284 iov[1].iov_len = sizeof(nla);
285
286 iov[2].iov_base = (void *) payload_data;
287 iov[2].iov_len = NLA_ALIGN(payload_len);
288
289 nl_complete_msg(nlh, nlmsg);
290 err = nl_send_iovec(nlh, nlmsg, iov, 3);
291
292 nlmsg_free(nlmsg);
293 if (err < 0)
294 return err;
295 return wait_for_ack(nlh);
296 }
297
298 #define NFNLMSG_QUEUE_TYPE(type) NFNLMSG_TYPE(NFNL_SUBSYS_QUEUE, (type))
299 static struct nl_cache_ops nfnl_queue_msg_ops = {
300 .co_name = "netfilter/queue_msg",
301 .co_hdrsize = NFNL_HDRLEN,
302 .co_msgtypes = {
303 { NFNLMSG_QUEUE_TYPE(NFQNL_MSG_PACKET), NL_ACT_NEW, "new" },
304 END_OF_MSGTYPES_LIST,
305 },
306 .co_protocol = NETLINK_NETFILTER,
307 .co_msg_parser = queue_msg_parser,
308 .co_obj_ops = &queue_msg_obj_ops,
309 };
310
nfnl_msg_queue_init(void)311 static void __init nfnl_msg_queue_init(void)
312 {
313 nl_cache_mngt_register(&nfnl_queue_msg_ops);
314 }
315
nfnl_queue_msg_exit(void)316 static void __exit nfnl_queue_msg_exit(void)
317 {
318 nl_cache_mngt_unregister(&nfnl_queue_msg_ops);
319 }
320
321 /** @} */
322