ip: fix mc_loop checks for tunnels with multicast outer addresses
[linux-2.6.git] / net / sched / em_text.c
1 /*
2  * net/sched/em_text.c  Textsearch ematch
3  *
4  *              This program is free software; you can redistribute it and/or
5  *              modify it under the terms of the GNU General Public License
6  *              as published by the Free Software Foundation; either version
7  *              2 of the License, or (at your option) any later version.
8  *
9  * Authors:     Thomas Graf <tgraf@suug.ch>
10  */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/skbuff.h>
17 #include <linux/textsearch.h>
18 #include <linux/tc_ematch/tc_em_text.h>
19 #include <net/pkt_cls.h>
20
21 struct text_match
22 {
23         u16                     from_offset;
24         u16                     to_offset;
25         u8                      from_layer;
26         u8                      to_layer;
27         struct ts_config        *config;
28 };
29
30 #define EM_TEXT_PRIV(m) ((struct text_match *) (m)->data)
31
32 static int em_text_match(struct sk_buff *skb, struct tcf_ematch *m,
33                          struct tcf_pkt_info *info)
34 {
35         struct text_match *tm = EM_TEXT_PRIV(m);
36         int from, to;
37         struct ts_state state;
38
39         from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
40         from += tm->from_offset;
41
42         to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
43         to += tm->to_offset;
44
45         return skb_find_text(skb, from, to, tm->config, &state) != UINT_MAX;
46 }
47
48 static int em_text_change(struct tcf_proto *tp, void *data, int len,
49                           struct tcf_ematch *m)
50 {
51         struct text_match *tm;
52         struct tcf_em_text *conf = data;
53         struct ts_config *ts_conf;
54         int flags = 0;
55
56         if (len < sizeof(*conf) || len < (sizeof(*conf) + conf->pattern_len))
57                 return -EINVAL;
58
59         if (conf->from_layer > conf->to_layer)
60                 return -EINVAL;
61
62         if (conf->from_layer == conf->to_layer &&
63             conf->from_offset > conf->to_offset)
64                 return -EINVAL;
65
66 retry:
67         ts_conf = textsearch_prepare(conf->algo, (u8 *) conf + sizeof(*conf),
68                                      conf->pattern_len, GFP_KERNEL, flags);
69
70         if (flags & TS_AUTOLOAD)
71                 rtnl_lock();
72
73         if (IS_ERR(ts_conf)) {
74                 if (PTR_ERR(ts_conf) == -ENOENT && !(flags & TS_AUTOLOAD)) {
75                         rtnl_unlock();
76                         flags |= TS_AUTOLOAD;
77                         goto retry;
78                 } else
79                         return PTR_ERR(ts_conf);
80         } else if (flags & TS_AUTOLOAD) {
81                 textsearch_destroy(ts_conf);
82                 return -EAGAIN;
83         }
84
85         tm = kmalloc(sizeof(*tm), GFP_KERNEL);
86         if (tm == NULL) {
87                 textsearch_destroy(ts_conf);
88                 return -ENOBUFS;
89         }
90
91         tm->from_offset = conf->from_offset;
92         tm->to_offset   = conf->to_offset;
93         tm->from_layer  = conf->from_layer;
94         tm->to_layer    = conf->to_layer;
95         tm->config      = ts_conf;
96
97         m->datalen = sizeof(*tm);
98         m->data = (unsigned long) tm;
99
100         return 0;
101 }
102
103 static void em_text_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
104 {
105         textsearch_destroy(EM_TEXT_PRIV(m)->config);
106 }
107
108 static int em_text_dump(struct sk_buff *skb, struct tcf_ematch *m)
109 {
110         struct text_match *tm = EM_TEXT_PRIV(m);
111         struct tcf_em_text conf;
112
113         strncpy(conf.algo, tm->config->ops->name, sizeof(conf.algo) - 1);
114         conf.from_offset = tm->from_offset;
115         conf.to_offset = tm->to_offset;
116         conf.from_layer = tm->from_layer;
117         conf.to_layer = tm->to_layer;
118         conf.pattern_len = textsearch_get_pattern_len(tm->config);
119         conf.pad = 0;
120
121         if (nla_put_nohdr(skb, sizeof(conf), &conf) < 0)
122                 goto nla_put_failure;
123         if (nla_append(skb, conf.pattern_len,
124                        textsearch_get_pattern(tm->config)) < 0)
125                 goto nla_put_failure;
126         return 0;
127
128 nla_put_failure:
129         return -1;
130 }
131
132 static struct tcf_ematch_ops em_text_ops = {
133         .kind     = TCF_EM_TEXT,
134         .change   = em_text_change,
135         .match    = em_text_match,
136         .destroy  = em_text_destroy,
137         .dump     = em_text_dump,
138         .owner    = THIS_MODULE,
139         .link     = LIST_HEAD_INIT(em_text_ops.link)
140 };
141
142 static int __init init_em_text(void)
143 {
144         return tcf_em_register(&em_text_ops);
145 }
146
147 static void __exit exit_em_text(void)
148 {
149         tcf_em_unregister(&em_text_ops);
150 }
151
152 MODULE_LICENSE("GPL");
153
154 module_init(init_em_text);
155 module_exit(exit_em_text);
156
157 MODULE_ALIAS_TCF_EMATCH(TCF_EM_TEXT);