Root/
1 | /* (C) 1999-2001 Paul `Rusty' Russell |
2 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify |
5 | * it under the terms of the GNU General Public License version 2 as |
6 | * published by the Free Software Foundation. |
7 | */ |
8 | |
9 | #include <linux/types.h> |
10 | #include <linux/timer.h> |
11 | #include <linux/module.h> |
12 | #include <linux/udp.h> |
13 | #include <linux/seq_file.h> |
14 | #include <linux/skbuff.h> |
15 | #include <linux/ipv6.h> |
16 | #include <net/ip6_checksum.h> |
17 | #include <net/checksum.h> |
18 | |
19 | #include <linux/netfilter.h> |
20 | #include <linux/netfilter_ipv4.h> |
21 | #include <linux/netfilter_ipv6.h> |
22 | #include <net/netfilter/nf_conntrack_l4proto.h> |
23 | #include <net/netfilter/nf_conntrack_ecache.h> |
24 | #include <net/netfilter/nf_log.h> |
25 | #include <net/netfilter/ipv4/nf_conntrack_ipv4.h> |
26 | #include <net/netfilter/ipv6/nf_conntrack_ipv6.h> |
27 | |
28 | static unsigned int nf_ct_udp_timeout __read_mostly = 30*HZ; |
29 | static unsigned int nf_ct_udp_timeout_stream __read_mostly = 180*HZ; |
30 | |
31 | static bool udp_pkt_to_tuple(const struct sk_buff *skb, |
32 | unsigned int dataoff, |
33 | struct nf_conntrack_tuple *tuple) |
34 | { |
35 | const struct udphdr *hp; |
36 | struct udphdr _hdr; |
37 | |
38 | /* Actually only need first 8 bytes. */ |
39 | hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); |
40 | if (hp == NULL) |
41 | return false; |
42 | |
43 | tuple->src.u.udp.port = hp->source; |
44 | tuple->dst.u.udp.port = hp->dest; |
45 | |
46 | return true; |
47 | } |
48 | |
49 | static bool udp_invert_tuple(struct nf_conntrack_tuple *tuple, |
50 | const struct nf_conntrack_tuple *orig) |
51 | { |
52 | tuple->src.u.udp.port = orig->dst.u.udp.port; |
53 | tuple->dst.u.udp.port = orig->src.u.udp.port; |
54 | return true; |
55 | } |
56 | |
57 | /* Print out the per-protocol part of the tuple. */ |
58 | static int udp_print_tuple(struct seq_file *s, |
59 | const struct nf_conntrack_tuple *tuple) |
60 | { |
61 | return seq_printf(s, "sport=%hu dport=%hu ", |
62 | ntohs(tuple->src.u.udp.port), |
63 | ntohs(tuple->dst.u.udp.port)); |
64 | } |
65 | |
66 | /* Returns verdict for packet, and may modify conntracktype */ |
67 | static int udp_packet(struct nf_conn *ct, |
68 | const struct sk_buff *skb, |
69 | unsigned int dataoff, |
70 | enum ip_conntrack_info ctinfo, |
71 | u_int8_t pf, |
72 | unsigned int hooknum) |
73 | { |
74 | /* If we've seen traffic both ways, this is some kind of UDP |
75 | stream. Extend timeout. */ |
76 | if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { |
77 | nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_udp_timeout_stream); |
78 | /* Also, more likely to be important, and not a probe */ |
79 | if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status)) |
80 | nf_conntrack_event_cache(IPCT_STATUS, ct); |
81 | } else |
82 | nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_udp_timeout); |
83 | |
84 | return NF_ACCEPT; |
85 | } |
86 | |
87 | /* Called when a new connection for this protocol found. */ |
88 | static bool udp_new(struct nf_conn *ct, const struct sk_buff *skb, |
89 | unsigned int dataoff) |
90 | { |
91 | return true; |
92 | } |
93 | |
94 | static int udp_error(struct net *net, struct sk_buff *skb, unsigned int dataoff, |
95 | enum ip_conntrack_info *ctinfo, |
96 | u_int8_t pf, |
97 | unsigned int hooknum) |
98 | { |
99 | unsigned int udplen = skb->len - dataoff; |
100 | const struct udphdr *hdr; |
101 | struct udphdr _hdr; |
102 | |
103 | /* Header is too small? */ |
104 | hdr = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); |
105 | if (hdr == NULL) { |
106 | if (LOG_INVALID(net, IPPROTO_UDP)) |
107 | nf_log_packet(pf, 0, skb, NULL, NULL, NULL, |
108 | "nf_ct_udp: short packet "); |
109 | return -NF_ACCEPT; |
110 | } |
111 | |
112 | /* Truncated/malformed packets */ |
113 | if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) { |
114 | if (LOG_INVALID(net, IPPROTO_UDP)) |
115 | nf_log_packet(pf, 0, skb, NULL, NULL, NULL, |
116 | "nf_ct_udp: truncated/malformed packet "); |
117 | return -NF_ACCEPT; |
118 | } |
119 | |
120 | /* Packet with no checksum */ |
121 | if (!hdr->check) |
122 | return NF_ACCEPT; |
123 | |
124 | /* Checksum invalid? Ignore. |
125 | * We skip checking packets on the outgoing path |
126 | * because the checksum is assumed to be correct. |
127 | * FIXME: Source route IP option packets --RR */ |
128 | if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING && |
129 | nf_checksum(skb, hooknum, dataoff, IPPROTO_UDP, pf)) { |
130 | if (LOG_INVALID(net, IPPROTO_UDP)) |
131 | nf_log_packet(pf, 0, skb, NULL, NULL, NULL, |
132 | "nf_ct_udp: bad UDP checksum "); |
133 | return -NF_ACCEPT; |
134 | } |
135 | |
136 | return NF_ACCEPT; |
137 | } |
138 | |
139 | #ifdef CONFIG_SYSCTL |
140 | static unsigned int udp_sysctl_table_users; |
141 | static struct ctl_table_header *udp_sysctl_header; |
142 | static struct ctl_table udp_sysctl_table[] = { |
143 | { |
144 | .procname = "nf_conntrack_udp_timeout", |
145 | .data = &nf_ct_udp_timeout, |
146 | .maxlen = sizeof(unsigned int), |
147 | .mode = 0644, |
148 | .proc_handler = proc_dointvec_jiffies, |
149 | }, |
150 | { |
151 | .procname = "nf_conntrack_udp_timeout_stream", |
152 | .data = &nf_ct_udp_timeout_stream, |
153 | .maxlen = sizeof(unsigned int), |
154 | .mode = 0644, |
155 | .proc_handler = proc_dointvec_jiffies, |
156 | }, |
157 | { |
158 | .ctl_name = 0 |
159 | } |
160 | }; |
161 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT |
162 | static struct ctl_table udp_compat_sysctl_table[] = { |
163 | { |
164 | .procname = "ip_conntrack_udp_timeout", |
165 | .data = &nf_ct_udp_timeout, |
166 | .maxlen = sizeof(unsigned int), |
167 | .mode = 0644, |
168 | .proc_handler = proc_dointvec_jiffies, |
169 | }, |
170 | { |
171 | .procname = "ip_conntrack_udp_timeout_stream", |
172 | .data = &nf_ct_udp_timeout_stream, |
173 | .maxlen = sizeof(unsigned int), |
174 | .mode = 0644, |
175 | .proc_handler = proc_dointvec_jiffies, |
176 | }, |
177 | { |
178 | .ctl_name = 0 |
179 | } |
180 | }; |
181 | #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ |
182 | #endif /* CONFIG_SYSCTL */ |
183 | |
184 | struct nf_conntrack_l4proto nf_conntrack_l4proto_udp4 __read_mostly = |
185 | { |
186 | .l3proto = PF_INET, |
187 | .l4proto = IPPROTO_UDP, |
188 | .name = "udp", |
189 | .pkt_to_tuple = udp_pkt_to_tuple, |
190 | .invert_tuple = udp_invert_tuple, |
191 | .print_tuple = udp_print_tuple, |
192 | .packet = udp_packet, |
193 | .new = udp_new, |
194 | .error = udp_error, |
195 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
196 | .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, |
197 | .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, |
198 | .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, |
199 | .nla_policy = nf_ct_port_nla_policy, |
200 | #endif |
201 | #ifdef CONFIG_SYSCTL |
202 | .ctl_table_users = &udp_sysctl_table_users, |
203 | .ctl_table_header = &udp_sysctl_header, |
204 | .ctl_table = udp_sysctl_table, |
205 | #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT |
206 | .ctl_compat_table = udp_compat_sysctl_table, |
207 | #endif |
208 | #endif |
209 | }; |
210 | EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp4); |
211 | |
212 | struct nf_conntrack_l4proto nf_conntrack_l4proto_udp6 __read_mostly = |
213 | { |
214 | .l3proto = PF_INET6, |
215 | .l4proto = IPPROTO_UDP, |
216 | .name = "udp", |
217 | .pkt_to_tuple = udp_pkt_to_tuple, |
218 | .invert_tuple = udp_invert_tuple, |
219 | .print_tuple = udp_print_tuple, |
220 | .packet = udp_packet, |
221 | .new = udp_new, |
222 | .error = udp_error, |
223 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
224 | .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, |
225 | .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, |
226 | .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, |
227 | .nla_policy = nf_ct_port_nla_policy, |
228 | #endif |
229 | #ifdef CONFIG_SYSCTL |
230 | .ctl_table_users = &udp_sysctl_table_users, |
231 | .ctl_table_header = &udp_sysctl_header, |
232 | .ctl_table = udp_sysctl_table, |
233 | #endif |
234 | }; |
235 | EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_udp6); |
236 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9