libnetfilter_conntrack  1.0.6
expect/build.c
1 /*
2  * (C) 2005-2011 by Pablo Neira Ayuso <pablo@netfilter.org>
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  */
9 
10 #include "internal/internal.h"
11 
12 static void __build_timeout(struct nfnlhdr *req,
13  size_t size,
14  const struct nf_expect *exp)
15 {
16  nfnl_addattr32(&req->nlh, size, CTA_EXPECT_TIMEOUT,htonl(exp->timeout));
17 }
18 
19 static void __build_zone(struct nfnlhdr *req, size_t size,
20  const struct nf_expect *exp)
21 {
22  nfnl_addattr16(&req->nlh, size, CTA_EXPECT_ZONE, htons(exp->zone));
23 }
24 
25 static void __build_flags(struct nfnlhdr *req,
26  size_t size, const struct nf_expect *exp)
27 {
28  nfnl_addattr32(&req->nlh, size, CTA_EXPECT_FLAGS,htonl(exp->flags));
29 }
30 
31 static void __build_class(struct nfnlhdr *req,
32  size_t size,
33  const struct nf_expect *exp)
34 {
35  nfnl_addattr32(&req->nlh, size, CTA_EXPECT_CLASS, htonl(exp->class));
36 }
37 
38 static void __build_helper_name(struct nfnlhdr *req, size_t size,
39  const struct nf_expect *exp)
40 {
41  nfnl_addattr_l(&req->nlh, size, CTA_EXPECT_HELP_NAME,
42  exp->helper_name, strlen(exp->helper_name)+1);
43 }
44 
45 static void __build_expectfn(struct nfnlhdr *req,
46  size_t size, const struct nf_expect *exp)
47 {
48  nfnl_addattr_l(&req->nlh, size, CTA_EXPECT_FN,
49  exp->expectfn, strlen(exp->expectfn)+1);
50 }
51 
52 int __build_expect(struct nfnl_subsys_handle *ssh,
53  struct nfnlhdr *req,
54  size_t size,
55  uint16_t type,
56  uint16_t flags,
57  const struct nf_expect *exp)
58 {
59  uint8_t l3num;
60 
61  if (test_bit(ATTR_ORIG_L3PROTO, exp->master.set))
62  l3num = exp->master.orig.l3protonum;
63  else if (test_bit(ATTR_ORIG_L3PROTO, exp->expected.set))
64  l3num = exp->expected.orig.l3protonum;
65  else
66  return -1;
67 
68  memset(req, 0, size);
69 
70  nfnl_fill_hdr(ssh, &req->nlh, 0, l3num, 0, type, flags);
71 
72  if (test_bit(ATTR_EXP_EXPECTED, exp->set)) {
73  __build_tuple(req, size, &exp->expected.orig, CTA_EXPECT_TUPLE);
74  }
75 
76  if (test_bit(ATTR_EXP_MASTER, exp->set)) {
77  __build_tuple(req, size, &exp->master.orig, CTA_EXPECT_MASTER);
78  }
79 
80  if (test_bit(ATTR_EXP_MASK, exp->set)) {
81  __build_tuple(req, size, &exp->mask.orig, CTA_EXPECT_MASK);
82  }
83 
84  if (test_bit(ATTR_EXP_NAT_TUPLE, exp->set) &&
85  test_bit(ATTR_EXP_NAT_DIR, exp->set)) {
86  struct nfattr *nest;
87 
88  nest = nfnl_nest(&req->nlh, size, CTA_EXPECT_NAT);
89  __build_tuple(req, size, &exp->nat.orig, CTA_EXPECT_NAT_TUPLE);
90  nfnl_addattr32(&req->nlh, size, CTA_EXPECT_NAT_DIR,
91  htonl(exp->nat_dir));
92  nfnl_nest_end(&req->nlh, nest);
93  }
94 
95  if (test_bit(ATTR_EXP_TIMEOUT, exp->set))
96  __build_timeout(req, size, exp);
97  if (test_bit(ATTR_EXP_FLAGS, exp->set))
98  __build_flags(req, size, exp);
99  if (test_bit(ATTR_EXP_ZONE, exp->set))
100  __build_zone(req, size, exp);
101  if (test_bit(ATTR_EXP_CLASS, exp->set))
102  __build_class(req, size, exp);
103  if (test_bit(ATTR_EXP_HELPER_NAME, exp->set))
104  __build_helper_name(req, size, exp);
105  if (test_bit(ATTR_EXP_FN, exp->set))
106  __build_expectfn(req, size, exp);
107 
108  return 0;
109 }