Automerge with /usr/src/ntfs-2.6.git.
[linux-2.6] / 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/config.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/sched.h>
17 #include <linux/string.h>
18 #include <linux/skbuff.h>
19 #include <linux/textsearch.h>
20 #include <linux/tc_ematch/tc_em_text.h>
21 #include <net/pkt_cls.h>
22
23 struct text_match
24 {
25         u16                     from_offset;
26         u16                     to_offset;
27         u8                      from_layer;
28         u8                      to_layer;
29         struct ts_config        *config;
30 };
31
32 #define EM_TEXT_PRIV(m) ((struct text_match *) (m)->data)
33
34 static int em_text_match(struct sk_buff *skb, struct tcf_ematch *m,
35                          struct tcf_pkt_info *info)
36 {
37         struct text_match *tm = EM_TEXT_PRIV(m);
38         int from, to;
39         struct ts_state state;
40
41         from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
42         from += tm->from_offset;
43
44         to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
45         to += tm->to_offset;
46
47         return skb_find_text(skb, from, to, tm->config, &state) != UINT_MAX;
48 }
49
50 static int em_text_change(struct tcf_proto *tp, void *data, int len,
51                           struct tcf_ematch *m)
52 {
53         struct text_match *tm;
54         struct tcf_em_text *conf = data;
55         struct ts_config *ts_conf;
56         int flags = 0;
57
58         printk("Configuring text: %s from %d:%d to %d:%d len %d\n", conf->algo, conf->from_offset,
59             conf->from_layer, conf->to_offset, conf->to_layer, conf->pattern_len);
60
61         if (len < sizeof(*conf) || len < (sizeof(*conf) + conf->pattern_len))
62                 return -EINVAL;
63
64         if (conf->from_layer > conf->to_layer)
65                 return -EINVAL;
66
67         if (conf->from_layer == conf->to_layer &&
68             conf->from_offset > conf->to_offset)
69                 return -EINVAL;
70
71 retry:
72         ts_conf = textsearch_prepare(conf->algo, (u8 *) conf + sizeof(*conf),
73                                      conf->pattern_len, GFP_KERNEL, flags);
74
75         if (flags & TS_AUTOLOAD)
76                 rtnl_lock();
77
78         if (IS_ERR(ts_conf)) {
79                 if (PTR_ERR(ts_conf) == -ENOENT && !(flags & TS_AUTOLOAD)) {
80                         rtnl_unlock();
81                         flags |= TS_AUTOLOAD;
82                         goto retry;
83                 } else
84                         return PTR_ERR(ts_conf);
85         } else if (flags & TS_AUTOLOAD) {
86                 textsearch_destroy(ts_conf);
87                 return -EAGAIN;
88         }
89
90         tm = kmalloc(sizeof(*tm), GFP_KERNEL);
91         if (tm == NULL) {
92                 textsearch_destroy(ts_conf);
93                 return -ENOBUFS;
94         }
95
96         tm->from_offset = conf->from_offset;
97         tm->to_offset   = conf->to_offset;
98         tm->from_layer  = conf->from_layer;
99         tm->to_layer    = conf->to_layer;
100         tm->config      = ts_conf;
101
102         m->datalen = sizeof(*tm);
103         m->data = (unsigned long) tm;
104
105         return 0;
106 }
107
108 static void em_text_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
109 {
110         textsearch_destroy(EM_TEXT_PRIV(m)->config);
111 }
112
113 static int em_text_dump(struct sk_buff *skb, struct tcf_ematch *m)
114 {
115         struct text_match *tm = EM_TEXT_PRIV(m);
116         struct tcf_em_text conf;
117
118         strncpy(conf.algo, tm->config->ops->name, sizeof(conf.algo) - 1);
119         conf.from_offset = tm->from_offset;
120         conf.to_offset = tm->to_offset;
121         conf.from_layer = tm->from_layer;
122         conf.to_layer = tm->to_layer;
123         conf.pattern_len = textsearch_get_pattern_len(tm->config);
124         conf.pad = 0;
125
126         RTA_PUT_NOHDR(skb, sizeof(conf), &conf);
127         RTA_APPEND(skb, conf.pattern_len, textsearch_get_pattern(tm->config));
128         return 0;
129
130 rtattr_failure:
131         return -1;
132 }               
133
134 static struct tcf_ematch_ops em_text_ops = {
135         .kind     = TCF_EM_TEXT,
136         .change   = em_text_change,
137         .match    = em_text_match,
138         .destroy  = em_text_destroy,
139         .dump     = em_text_dump,
140         .owner    = THIS_MODULE,
141         .link     = LIST_HEAD_INIT(em_text_ops.link)
142 };
143
144 static int __init init_em_text(void)
145 {
146         return tcf_em_register(&em_text_ops);
147 }
148
149 static void __exit exit_em_text(void) 
150 {
151         tcf_em_unregister(&em_text_ops);
152 }
153
154 MODULE_LICENSE("GPL");
155
156 module_init(init_em_text);
157 module_exit(exit_em_text);