dm thin: wake worker when discard is prepared
[linux-2.6.git] / net / netfilter / nf_conntrack_amanda.c
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1 /* Amanda extension for IP connection tracking
3 * (C) 2002 by Brian J. Murrell <netfilter@interlinx.bc.ca>
4 * based on HW's ip_conntrack_irc.c as well as other modules
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/textsearch.h>
15 #include <linux/skbuff.h>
16 #include <linux/in.h>
17 #include <linux/udp.h>
18 #include <linux/netfilter.h>
19 #include <linux/gfp.h>
21 #include <net/netfilter/nf_conntrack.h>
22 #include <net/netfilter/nf_conntrack_expect.h>
23 #include <net/netfilter/nf_conntrack_ecache.h>
24 #include <net/netfilter/nf_conntrack_helper.h>
25 #include <linux/netfilter/nf_conntrack_amanda.h>
27 static unsigned int master_timeout __read_mostly = 300;
28 static char *ts_algo = "kmp";
30 MODULE_AUTHOR("Brian J. Murrell <netfilter@interlinx.bc.ca>");
31 MODULE_DESCRIPTION("Amanda connection tracking module");
32 MODULE_LICENSE("GPL");
33 MODULE_ALIAS("ip_conntrack_amanda");
34 MODULE_ALIAS_NFCT_HELPER("amanda");
36 module_param(master_timeout, uint, 0600);
37 MODULE_PARM_DESC(master_timeout, "timeout for the master connection");
38 module_param(ts_algo, charp, 0400);
39 MODULE_PARM_DESC(ts_algo, "textsearch algorithm to use (default kmp)");
41 unsigned int (*nf_nat_amanda_hook)(struct sk_buff *skb,
42 enum ip_conntrack_info ctinfo,
43 unsigned int protoff,
44 unsigned int matchoff,
45 unsigned int matchlen,
46 struct nf_conntrack_expect *exp)
47 __read_mostly;
48 EXPORT_SYMBOL_GPL(nf_nat_amanda_hook);
50 enum amanda_strings {
51 SEARCH_CONNECT,
52 SEARCH_NEWLINE,
53 SEARCH_DATA,
54 SEARCH_MESG,
55 SEARCH_INDEX,
58 static struct {
59 const char *string;
60 size_t len;
61 struct ts_config *ts;
62 } search[] __read_mostly = {
63 [SEARCH_CONNECT] = {
64 .string = "CONNECT ",
65 .len = 8,
67 [SEARCH_NEWLINE] = {
68 .string = "\n",
69 .len = 1,
71 [SEARCH_DATA] = {
72 .string = "DATA ",
73 .len = 5,
75 [SEARCH_MESG] = {
76 .string = "MESG ",
77 .len = 5,
79 [SEARCH_INDEX] = {
80 .string = "INDEX ",
81 .len = 6,
85 static int amanda_help(struct sk_buff *skb,
86 unsigned int protoff,
87 struct nf_conn *ct,
88 enum ip_conntrack_info ctinfo)
90 struct ts_state ts;
91 struct nf_conntrack_expect *exp;
92 struct nf_conntrack_tuple *tuple;
93 unsigned int dataoff, start, stop, off, i;
94 char pbuf[sizeof("65535")], *tmp;
95 u_int16_t len;
96 __be16 port;
97 int ret = NF_ACCEPT;
98 typeof(nf_nat_amanda_hook) nf_nat_amanda;
100 /* Only look at packets from the Amanda server */
101 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
102 return NF_ACCEPT;
104 /* increase the UDP timeout of the master connection as replies from
105 * Amanda clients to the server can be quite delayed */
106 nf_ct_refresh(ct, skb, master_timeout * HZ);
108 /* No data? */
109 dataoff = protoff + sizeof(struct udphdr);
110 if (dataoff >= skb->len) {
111 net_err_ratelimited("amanda_help: skblen = %u\n", skb->len);
112 return NF_ACCEPT;
115 memset(&ts, 0, sizeof(ts));
116 start = skb_find_text(skb, dataoff, skb->len,
117 search[SEARCH_CONNECT].ts, &ts);
118 if (start == UINT_MAX)
119 goto out;
120 start += dataoff + search[SEARCH_CONNECT].len;
122 memset(&ts, 0, sizeof(ts));
123 stop = skb_find_text(skb, start, skb->len,
124 search[SEARCH_NEWLINE].ts, &ts);
125 if (stop == UINT_MAX)
126 goto out;
127 stop += start;
129 for (i = SEARCH_DATA; i <= SEARCH_INDEX; i++) {
130 memset(&ts, 0, sizeof(ts));
131 off = skb_find_text(skb, start, stop, search[i].ts, &ts);
132 if (off == UINT_MAX)
133 continue;
134 off += start + search[i].len;
136 len = min_t(unsigned int, sizeof(pbuf) - 1, stop - off);
137 if (skb_copy_bits(skb, off, pbuf, len))
138 break;
139 pbuf[len] = '\0';
141 port = htons(simple_strtoul(pbuf, &tmp, 10));
142 len = tmp - pbuf;
143 if (port == 0 || len > 5)
144 break;
146 exp = nf_ct_expect_alloc(ct);
147 if (exp == NULL) {
148 ret = NF_DROP;
149 goto out;
151 tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
152 nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT,
153 nf_ct_l3num(ct),
154 &tuple->src.u3, &tuple->dst.u3,
155 IPPROTO_TCP, NULL, &port);
157 nf_nat_amanda = rcu_dereference(nf_nat_amanda_hook);
158 if (nf_nat_amanda && ct->status & IPS_NAT_MASK)
159 ret = nf_nat_amanda(skb, ctinfo, protoff,
160 off - dataoff, len, exp);
161 else if (nf_ct_expect_related(exp) != 0)
162 ret = NF_DROP;
163 nf_ct_expect_put(exp);
166 out:
167 return ret;
170 static const struct nf_conntrack_expect_policy amanda_exp_policy = {
171 .max_expected = 3,
172 .timeout = 180,
175 static struct nf_conntrack_helper amanda_helper[2] __read_mostly = {
177 .name = "amanda",
178 .me = THIS_MODULE,
179 .help = amanda_help,
180 .tuple.src.l3num = AF_INET,
181 .tuple.src.u.udp.port = cpu_to_be16(10080),
182 .tuple.dst.protonum = IPPROTO_UDP,
183 .expect_policy = &amanda_exp_policy,
186 .name = "amanda",
187 .me = THIS_MODULE,
188 .help = amanda_help,
189 .tuple.src.l3num = AF_INET6,
190 .tuple.src.u.udp.port = cpu_to_be16(10080),
191 .tuple.dst.protonum = IPPROTO_UDP,
192 .expect_policy = &amanda_exp_policy,
196 static void __exit nf_conntrack_amanda_fini(void)
198 int i;
200 nf_conntrack_helper_unregister(&amanda_helper[0]);
201 nf_conntrack_helper_unregister(&amanda_helper[1]);
202 for (i = 0; i < ARRAY_SIZE(search); i++)
203 textsearch_destroy(search[i].ts);
206 static int __init nf_conntrack_amanda_init(void)
208 int ret, i;
210 for (i = 0; i < ARRAY_SIZE(search); i++) {
211 search[i].ts = textsearch_prepare(ts_algo, search[i].string,
212 search[i].len,
213 GFP_KERNEL, TS_AUTOLOAD);
214 if (IS_ERR(search[i].ts)) {
215 ret = PTR_ERR(search[i].ts);
216 goto err1;
219 ret = nf_conntrack_helper_register(&amanda_helper[0]);
220 if (ret < 0)
221 goto err1;
222 ret = nf_conntrack_helper_register(&amanda_helper[1]);
223 if (ret < 0)
224 goto err2;
225 return 0;
227 err2:
228 nf_conntrack_helper_unregister(&amanda_helper[0]);
229 err1:
230 while (--i >= 0)
231 textsearch_destroy(search[i].ts);
233 return ret;
236 module_init(nf_conntrack_amanda_init);
237 module_exit(nf_conntrack_amanda_fini);