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
28static struct nl_cache_ops nfnl_queue_msg_ops;
29
30#if __BYTE_ORDER == __BIG_ENDIAN
31static uint64_t ntohll(uint64_t x)
32{
33	return x;
34}
35#elif __BYTE_ORDER == __LITTLE_ENDIAN
36static uint64_t ntohll(uint64_t x)
37{
38	return __bswap_64(x);
39}
40#endif
41
42static 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
62int 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
143errout:
144	nfnl_queue_msg_put(msg);
145	return err;
146}
147
148static 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);
158errout:
159	nfnl_queue_msg_put(msg);
160	return err;
161}
162
163/** @} */
164
165struct 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
188nla_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*/
199int 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*/
224int 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))
262static 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
274static void __init nfnl_msg_queue_init(void)
275{
276	nl_cache_mngt_register(&nfnl_queue_msg_ops);
277}
278
279static void __exit nfnl_queue_msg_exit(void)
280{
281	nl_cache_mngt_unregister(&nfnl_queue_msg_ops);
282}
283
284/** @} */
285