blob: df3110d695857e672f1a50f83399a7f63959dd00 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * net/sched/em_nbyte.c N-Byte 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
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090012#include <linux/gfp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/string.h>
17#include <linux/skbuff.h>
18#include <linux/tc_ematch/tc_em_nbyte.h>
19#include <net/pkt_cls.h>
20
Eric Dumazetcc7ec452011-01-19 19:26:56 +000021struct nbyte_data {
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 struct tcf_em_nbyte hdr;
23 char pattern[0];
24};
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090025
John Fastabend82a470f2014-10-05 21:27:53 -070026static int em_nbyte_change(struct net *net, void *data, int data_len,
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 struct tcf_ematch *em)
28{
29 struct tcf_em_nbyte *nbyte = data;
30
31 if (data_len < sizeof(*nbyte) ||
32 data_len < (sizeof(*nbyte) + nbyte->len))
33 return -EINVAL;
34
35 em->datalen = sizeof(*nbyte) + nbyte->len;
Arnaldo Carvalho de Meloc7b1b242006-11-21 01:19:40 -020036 em->data = (unsigned long)kmemdup(data, em->datalen, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 if (em->data == 0UL)
38 return -ENOBUFS;
39
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 return 0;
41}
42
43static int em_nbyte_match(struct sk_buff *skb, struct tcf_ematch *em,
44 struct tcf_pkt_info *info)
45{
46 struct nbyte_data *nbyte = (struct nbyte_data *) em->data;
47 unsigned char *ptr = tcf_get_base_ptr(skb, nbyte->hdr.layer);
48
49 ptr += nbyte->hdr.off;
50
51 if (!tcf_valid_offset(skb, ptr, nbyte->hdr.len))
52 return 0;
53
54 return !memcmp(ptr + nbyte->hdr.off, nbyte->pattern, nbyte->hdr.len);
55}
56
57static struct tcf_ematch_ops em_nbyte_ops = {
58 .kind = TCF_EM_NBYTE,
59 .change = em_nbyte_change,
60 .match = em_nbyte_match,
61 .owner = THIS_MODULE,
62 .link = LIST_HEAD_INIT(em_nbyte_ops.link)
63};
64
65static int __init init_em_nbyte(void)
66{
67 return tcf_em_register(&em_nbyte_ops);
68}
69
YOSHIFUJI Hideaki10297b92007-02-09 23:25:16 +090070static void __exit exit_em_nbyte(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -070071{
72 tcf_em_unregister(&em_nbyte_ops);
73}
74
75MODULE_LICENSE("GPL");
76
77module_init(init_em_nbyte);
78module_exit(exit_em_nbyte);
Patrick McHardydb3d99c2007-07-11 19:46:26 -070079
80MODULE_ALIAS_TCF_EMATCH(TCF_EM_NBYTE);