libnl  3.5.0
queue.c
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3  * lib/netfilter/queue.c Netfilter Queue
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation version 2.1
8  * of the License.
9  *
10  * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
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.h>
27 
28 struct nl_sock *nfnl_queue_socket_alloc(void)
29 {
30  struct nl_sock *nlsk;
31 
32  nlsk = nl_socket_alloc();
33  if (nlsk)
35  return nlsk;
36 }
37 
38 static int send_queue_request(struct nl_sock *sk, struct nl_msg *msg)
39 {
40  int err;
41 
42  err = nl_send_auto_complete(sk, msg);
43  nlmsg_free(msg);
44  if (err < 0)
45  return err;
46 
47  return wait_for_ack(sk);
48 }
49 
50 /**
51  * @name Queue Commands
52  * @{
53  */
54 
55 static int build_queue_cmd_request(uint8_t family, uint16_t queuenum,
56  uint8_t command, struct nl_msg **result)
57 {
58  struct nl_msg *msg;
59  struct nfqnl_msg_config_cmd cmd;
60 
61  msg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, NFQNL_MSG_CONFIG, 0,
62  family, queuenum);
63  if (msg == NULL)
64  return -NLE_NOMEM;
65 
66  cmd.pf = htons(family);
67  cmd._pad = 0;
68  cmd.command = command;
69  if (nla_put(msg, NFQA_CFG_CMD, sizeof(cmd), &cmd) < 0)
70  goto nla_put_failure;
71 
72  *result = msg;
73  return 0;
74 
75 nla_put_failure:
76  nlmsg_free(msg);
77  return -NLE_MSGSIZE;
78 }
79 
80 int nfnl_queue_build_pf_bind(uint8_t pf, struct nl_msg **result)
81 {
82  return build_queue_cmd_request(pf, 0, NFQNL_CFG_CMD_PF_BIND, result);
83 }
84 
85 int nfnl_queue_pf_bind(struct nl_sock *nlh, uint8_t pf)
86 {
87  struct nl_msg *msg;
88  int err;
89 
90  if ((err = nfnl_queue_build_pf_bind(pf, &msg)) < 0)
91  return err;
92 
93  return send_queue_request(nlh, msg);
94 }
95 
96 int nfnl_queue_build_pf_unbind(uint8_t pf, struct nl_msg **result)
97 {
98  return build_queue_cmd_request(pf, 0, NFQNL_CFG_CMD_PF_UNBIND, result);
99 }
100 
101 int nfnl_queue_pf_unbind(struct nl_sock *nlh, uint8_t pf)
102 {
103  struct nl_msg *msg;
104  int err;
105 
106  if ((err = nfnl_queue_build_pf_unbind(pf, &msg)) < 0)
107  return err;
108 
109  return send_queue_request(nlh, msg);
110 }
111 
112 static int nfnl_queue_build_request(const struct nfnl_queue *queue,
113  struct nl_msg **result)
114 {
115  struct nl_msg *msg;
116 
117  if (!nfnl_queue_test_group(queue))
118  return -NLE_MISSING_ATTR;
119 
120  msg = nfnlmsg_alloc_simple(NFNL_SUBSYS_QUEUE, NFQNL_MSG_CONFIG, 0,
121  0, nfnl_queue_get_group(queue));
122  if (msg == NULL)
123  return -NLE_NOMEM;
124 
125  if (nfnl_queue_test_maxlen(queue) &&
126  nla_put_u32(msg, NFQA_CFG_QUEUE_MAXLEN,
127  htonl(nfnl_queue_get_maxlen(queue))) < 0)
128  goto nla_put_failure;
129 
130  /* This sucks, the nfnetlink_queue interface always expects both
131  * parameters to be present. Needs to be done properly.
132  */
133  if (nfnl_queue_test_copy_mode(queue)) {
134  struct nfqnl_msg_config_params params;
135 
136  switch (nfnl_queue_get_copy_mode(queue)) {
137  case NFNL_QUEUE_COPY_NONE:
138  params.copy_mode = NFQNL_COPY_NONE;
139  break;
140  case NFNL_QUEUE_COPY_META:
141  params.copy_mode = NFQNL_COPY_META;
142  break;
143  case NFNL_QUEUE_COPY_PACKET:
144  params.copy_mode = NFQNL_COPY_PACKET;
145  break;
146  }
147  params.copy_range = htonl(nfnl_queue_get_copy_range(queue));
148 
149  if (nla_put(msg, NFQA_CFG_PARAMS, sizeof(params), &params) < 0)
150  goto nla_put_failure;
151  }
152 
153  *result = msg;
154  return 0;
155 
156 nla_put_failure:
157  nlmsg_free(msg);
158  return -NLE_MSGSIZE;
159 }
160 
161 int nfnl_queue_build_create_request(const struct nfnl_queue *queue,
162  struct nl_msg **result)
163 {
164  struct nfqnl_msg_config_cmd cmd;
165  int err;
166 
167  if ((err = nfnl_queue_build_request(queue, result)) < 0)
168  return err;
169 
170  cmd.pf = 0;
171  cmd._pad = 0;
172  cmd.command = NFQNL_CFG_CMD_BIND;
173 
174  NLA_PUT(*result, NFQA_CFG_CMD, sizeof(cmd), &cmd);
175 
176  return 0;
177 
178 nla_put_failure:
179  nlmsg_free(*result);
180  return -NLE_MSGSIZE;
181 }
182 
183 int nfnl_queue_create(struct nl_sock *nlh, const struct nfnl_queue *queue)
184 {
185  struct nl_msg *msg;
186  int err;
187 
188  if ((err = nfnl_queue_build_create_request(queue, &msg)) < 0)
189  return err;
190 
191  return send_queue_request(nlh, msg);
192 }
193 
194 int nfnl_queue_build_change_request(const struct nfnl_queue *queue,
195  struct nl_msg **result)
196 {
197  return nfnl_queue_build_request(queue, result);
198 }
199 
200 int nfnl_queue_change(struct nl_sock *nlh, const struct nfnl_queue *queue)
201 {
202  struct nl_msg *msg;
203  int err;
204 
205  if ((err = nfnl_queue_build_change_request(queue, &msg)) < 0)
206  return err;
207 
208  return send_queue_request(nlh, msg);
209 }
210 
211 int nfnl_queue_build_delete_request(const struct nfnl_queue *queue,
212  struct nl_msg **result)
213 {
214  if (!nfnl_queue_test_group(queue))
215  return -NLE_MISSING_ATTR;
216 
217  return build_queue_cmd_request(0, nfnl_queue_get_group(queue),
218  NFQNL_CFG_CMD_UNBIND, result);
219 }
220 
221 int nfnl_queue_delete(struct nl_sock *nlh, const struct nfnl_queue *queue)
222 {
223  struct nl_msg *msg;
224  int err;
225 
226  if ((err = nfnl_queue_build_delete_request(queue, &msg)) < 0)
227  return err;
228 
229  return send_queue_request(nlh, msg);
230 }
231 
232 /** @} */
233 
234 static struct nl_cache_ops nfnl_queue_ops = {
235  .co_name = "netfilter/queue",
236  .co_obj_ops = &queue_obj_ops,
237  .co_msgtypes = {
238  END_OF_MSGTYPES_LIST,
239  },
240 };
241 
242 static void __init nfnl_queue_init(void)
243 {
244  nl_cache_mngt_register(&nfnl_queue_ops);
245 }
246 
247 static void __exit nfnl_queue_exit(void)
248 {
249  nl_cache_mngt_unregister(&nfnl_queue_ops);
250 }
251 
252 /** @} */
int nl_send_auto_complete(struct nl_sock *sk, struct nl_msg *msg)
Definition: nl.c:1248
void nlmsg_free(struct nl_msg *msg)
Release a reference from an netlink message.
Definition: msg.c:565
int nl_cache_mngt_unregister(struct nl_cache_ops *ops)
Unregister a set of cache operations.
Definition: cache_mngt.c:288
void nl_socket_disable_auto_ack(struct nl_sock *sk)
Disable automatic request for ACK.
Definition: socket.c:315
struct nl_sock * nl_socket_alloc(void)
Allocate new netlink socket.
Definition: socket.c:206
int nl_cache_mngt_register(struct nl_cache_ops *ops)
Register a set of cache operations.
Definition: cache_mngt.c:253
#define NLA_PUT(msg, attrtype, attrlen, data)
Add unspecific attribute to netlink message.
Definition: attr.h:165
int nla_put_u32(struct nl_msg *msg, int attrtype, uint32_t value)
Add 32 bit integer attribute to netlink message.
Definition: attr.c:696
int nla_put(struct nl_msg *msg, int attrtype, int datalen, const void *data)
Add a unspecific attribute to netlink message.
Definition: attr.c:501
struct nl_msg * nfnlmsg_alloc_simple(uint8_t subsys_id, uint8_t type, int flags, uint8_t family, uint16_t res_id)
Allocate a new netfilter netlink message.
Definition: nfnl.c:204