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-local.h>
24 #include <netlink/attr.h>
25 #include <netlink/netfilter/nfnl.h>
26 #include <netlink/netfilter/queue_msg.h>
27
28 static struct nl_cache_ops nfnl_queue_msg_ops;
29
30 #if __BYTE_ORDER == __BIG_ENDIAN
ntohll(uint64_t x)31 static uint64_t ntohll(uint64_t x)
32 {
33 return x;
34 }
35 #elif __BYTE_ORDER == __LITTLE_ENDIAN
ntohll(uint64_t x)36 static uint64_t ntohll(uint64_t x)
37 {
38 return __bswap_64(x);
39 }
40 #endif
41
42 static struct nla_policy queue_policy[NFQA_MAX+1] = {
43 [NFQA_PACKET_HDR] = {
44 .minlen = sizeof(struct nfqnl_msg_packet_hdr),
45 },
46 [NFQA_VERDICT_HDR] = {
47 .minlen = sizeof(struct nfqnl_msg_verdict_hdr),
48 },
49 [NFQA_MARK] = { .type = NLA_U32 },
50 [NFQA_TIMESTAMP] = {
51 .minlen = sizeof(struct nfqnl_msg_packet_timestamp),
52 },
53 [NFQA_IFINDEX_INDEV] = { .type = NLA_U32 },
54 [NFQA_IFINDEX_OUTDEV] = { .type = NLA_U32 },
55 [NFQA_IFINDEX_PHYSINDEV] = { .type = NLA_U32 },
56 [NFQA_IFINDEX_PHYSOUTDEV] = { .type = NLA_U32 },
57 [NFQA_HWADDR] = {
58 .minlen = sizeof(struct nfqnl_msg_packet_hw),
59 },
60 };
61
nfnlmsg_queue_msg_parse(struct nlmsghdr * nlh,struct nfnl_queue_msg ** result)62 int nfnlmsg_queue_msg_parse(struct nlmsghdr *nlh,
63 struct nfnl_queue_msg **result)
64 {
65 struct nfnl_queue_msg *msg;
66 struct nlattr *tb[NFQA_MAX+1];
67 struct nlattr *attr;
68 int err;
69
70 msg = nfnl_queue_msg_alloc();
71 if (!msg)
72 return -NLE_NOMEM;
73
74 msg->ce_msgtype = nlh->nlmsg_type;
75
76 err = nlmsg_parse(nlh, sizeof(struct nfgenmsg), tb, NFQA_MAX,
77 queue_policy);
78 if (err < 0)
79 goto errout;
80
81 nfnl_queue_msg_set_group(msg, nfnlmsg_res_id(nlh));
82 nfnl_queue_msg_set_family(msg, nfnlmsg_family(nlh));
83
84 attr = tb[NFQA_PACKET_HDR];
85 if (attr) {
86 struct nfqnl_msg_packet_hdr *hdr = nla_data(attr);
87
88 nfnl_queue_msg_set_packetid(msg, ntohl(hdr->packet_id));
89 if (hdr->hw_protocol)
90 nfnl_queue_msg_set_hwproto(msg, hdr->hw_protocol);
91 nfnl_queue_msg_set_hook(msg, hdr->hook);
92 }
93
94 attr = tb[NFQA_MARK];
95 if (attr)
96 nfnl_queue_msg_set_mark(msg, ntohl(nla_get_u32(attr)));
97
98 attr = tb[NFQA_TIMESTAMP];
99 if (attr) {
100 struct nfqnl_msg_packet_timestamp *timestamp = nla_data(attr);
101 struct timeval tv;
102
103 tv.tv_sec = ntohll(timestamp->sec);
104 tv.tv_usec = ntohll(timestamp->usec);
105 nfnl_queue_msg_set_timestamp(msg, &tv);
106 }
107
108 attr = tb[NFQA_IFINDEX_INDEV];
109 if (attr)
110 nfnl_queue_msg_set_indev(msg, ntohl(nla_get_u32(attr)));
111
112 attr = tb[NFQA_IFINDEX_OUTDEV];
113 if (attr)
114 nfnl_queue_msg_set_outdev(msg, ntohl(nla_get_u32(attr)));
115
116 attr = tb[NFQA_IFINDEX_PHYSINDEV];
117 if (attr)
118 nfnl_queue_msg_set_physindev(msg, ntohl(nla_get_u32(attr)));
119
120 attr = tb[NFQA_IFINDEX_PHYSOUTDEV];
121 if (attr)
122 nfnl_queue_msg_set_physoutdev(msg, ntohl(nla_get_u32(attr)));
123
124 attr = tb[NFQA_HWADDR];
125 if (attr) {
126 struct nfqnl_msg_packet_hw *hw = nla_data(attr);
127
128 nfnl_queue_msg_set_hwaddr(msg, hw->hw_addr,
129 ntohs(hw->hw_addrlen));
130 }
131
132 attr = tb[NFQA_PAYLOAD];
133 if (attr) {
134 err = nfnl_queue_msg_set_payload(msg, nla_data(attr),
135 nla_len(attr));
136 if (err < 0)
137 goto errout;
138 }
139
140 *result = msg;
141 return 0;
142
143 errout:
144 nfnl_queue_msg_put(msg);
145 return err;
146 }
147
queue_msg_parser(struct nl_cache_ops * ops,struct sockaddr_nl * who,struct nlmsghdr * nlh,struct nl_parser_param * pp)148 static int queue_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
149 struct nlmsghdr *nlh, struct nl_parser_param *pp)
150 {
151 struct nfnl_queue_msg *msg;
152 int err;
153
154 if ((err = nfnlmsg_queue_msg_parse(nlh, &msg)) < 0)
155 goto errout;
156
157 err = pp->pp_cb((struct nl_object *) msg, pp);
158 errout:
159 nfnl_queue_msg_put(msg);
160 return err;
161 }
162
163 /** @} */
164
nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg * msg)165 struct nl_msg *nfnl_queue_msg_build_verdict(const struct nfnl_queue_msg *msg)
166 {
167 struct nl_msg *nlmsg;
168 struct nfqnl_msg_verdict_hdr verdict;
169
170 nlmsg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, NFQNL_MSG_VERDICT, 0,
171 nfnl_queue_msg_get_family(msg),
172 nfnl_queue_msg_get_group(msg));
173 if (nlmsg == NULL)
174 return NULL;
175
176 verdict.id = htonl(nfnl_queue_msg_get_packetid(msg));
177 verdict.verdict = htonl(nfnl_queue_msg_get_verdict(msg));
178 if (nla_put(nlmsg, NFQA_VERDICT_HDR, sizeof(verdict), &verdict) < 0)
179 goto nla_put_failure;
180
181 if (nfnl_queue_msg_test_mark(msg) &&
182 nla_put_u32(nlmsg, NFQA_MARK,
183 ntohl(nfnl_queue_msg_get_mark(msg))) < 0)
184 goto nla_put_failure;
185
186 return nlmsg;
187
188 nla_put_failure:
189 nlmsg_free(nlmsg);
190 return NULL;
191 }
192
193 /**
194 * Send a message verdict/mark
195 * @arg nlh netlink messsage header
196 * @arg msg queue msg
197 * @return 0 on OK or error code
198 */
nfnl_queue_msg_send_verdict(struct nl_sock * nlh,const struct nfnl_queue_msg * msg)199 int nfnl_queue_msg_send_verdict(struct nl_sock *nlh,
200 const struct nfnl_queue_msg *msg)
201 {
202 struct nl_msg *nlmsg;
203 int err;
204
205 nlmsg = nfnl_queue_msg_build_verdict(msg);
206 if (nlmsg == NULL)
207 return -NLE_NOMEM;
208
209 err = nl_send_auto_complete(nlh, nlmsg);
210 nlmsg_free(nlmsg);
211 if (err < 0)
212 return err;
213 return wait_for_ack(nlh);
214 }
215
216 /**
217 * Send a message verdict including the payload
218 * @arg nlh netlink messsage header
219 * @arg msg queue msg
220 * @arg payload_data packet payload data
221 * @arg payload_len payload length
222 * @return 0 on OK or error code
223 */
nfnl_queue_msg_send_verdict_payload(struct nl_sock * nlh,const struct nfnl_queue_msg * msg,const void * payload_data,unsigned payload_len)224 int nfnl_queue_msg_send_verdict_payload(struct nl_sock *nlh,
225 const struct nfnl_queue_msg *msg,
226 const void *payload_data, unsigned payload_len)
227 {
228 struct nl_msg *nlmsg;
229 int err;
230 struct iovec iov[3];
231 struct nlattr nla;
232
233 nlmsg = nfnl_queue_msg_build_verdict(msg);
234 if (nlmsg == NULL)
235 return -NLE_NOMEM;
236
237 memset(iov, 0, sizeof(iov));
238
239 iov[0].iov_base = (void *) nlmsg_hdr(nlmsg);
240 iov[0].iov_len = nlmsg_hdr(nlmsg)->nlmsg_len;
241
242 nla.nla_type = NFQA_PAYLOAD;
243 nla.nla_len = payload_len + sizeof(nla);
244 nlmsg_hdr(nlmsg)->nlmsg_len += nla.nla_len;
245
246 iov[1].iov_base = (void *) &nla;
247 iov[1].iov_len = sizeof(nla);
248
249 iov[2].iov_base = (void *) payload_data;
250 iov[2].iov_len = NLA_ALIGN(payload_len);
251
252 nl_auto_complete(nlh, nlmsg);
253 err = nl_send_iovec(nlh, nlmsg, iov, 3);
254
255 nlmsg_free(nlmsg);
256 if (err < 0)
257 return err;
258 return wait_for_ack(nlh);
259 }
260
261 #define NFNLMSG_QUEUE_TYPE(type) NFNLMSG_TYPE(NFNL_SUBSYS_QUEUE, (type))
262 static struct nl_cache_ops nfnl_queue_msg_ops = {
263 .co_name = "netfilter/queue_msg",
264 .co_hdrsize = NFNL_HDRLEN,
265 .co_msgtypes = {
266 { NFNLMSG_QUEUE_TYPE(NFQNL_MSG_PACKET), NL_ACT_NEW, "new" },
267 END_OF_MSGTYPES_LIST,
268 },
269 .co_protocol = NETLINK_NETFILTER,
270 .co_msg_parser = queue_msg_parser,
271 .co_obj_ops = &queue_msg_obj_ops,
272 };
273
nfnl_msg_queue_init(void)274 static void __init nfnl_msg_queue_init(void)
275 {
276 nl_cache_mngt_register(&nfnl_queue_msg_ops);
277 }
278
nfnl_queue_msg_exit(void)279 static void __exit nfnl_queue_msg_exit(void)
280 {
281 nl_cache_mngt_unregister(&nfnl_queue_msg_ops);
282 }
283
284 /** @} */
285