[linux-2.6-block.git] / net / sched / em_text.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/sched/em_text.c	Textsearch ematch
 *
 * Authors:	Thomas Graf <tgraf@suug.ch>
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/textsearch.h>
#include <linux/tc_ematch/tc_em_text.h>
#include <net/pkt_cls.h>

struct text_match {
	u16			from_offset;
	u16			to_offset;
	u8			from_layer;
	u8			to_layer;
	struct ts_config	*config;
};

#define EM_TEXT_PRIV(m) ((struct text_match *) (m)->data)

static int em_text_match(struct sk_buff *skb, struct tcf_ematch *m,
			 struct tcf_pkt_info *info)
{
	struct text_match *tm = EM_TEXT_PRIV(m);
	int from, to;

	from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
	from += tm->from_offset;

	to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
	to += tm->to_offset;

	return skb_find_text(skb, from, to, tm->config) != UINT_MAX;
}

static int em_text_change(struct net *net, void *data, int len,
			  struct tcf_ematch *m)
{
	struct text_match *tm;
	struct tcf_em_text *conf = data;
	struct ts_config *ts_conf;
	int flags = 0;

	if (len < sizeof(*conf) || len < (sizeof(*conf) + conf->pattern_len))
		return -EINVAL;

	if (conf->from_layer > conf->to_layer)
		return -EINVAL;

	if (conf->from_layer == conf->to_layer &&
	    conf->from_offset > conf->to_offset)
		return -EINVAL;

retry:
	ts_conf = textsearch_prepare(conf->algo, (u8 *) conf + sizeof(*conf),
				     conf->pattern_len, GFP_KERNEL, flags);

	if (flags & TS_AUTOLOAD)
		rtnl_lock();

	if (IS_ERR(ts_conf)) {
		if (PTR_ERR(ts_conf) == -ENOENT && !(flags & TS_AUTOLOAD)) {
			rtnl_unlock();
			flags |= TS_AUTOLOAD;
			goto retry;
		} else
			return PTR_ERR(ts_conf);
	} else if (flags & TS_AUTOLOAD) {
		textsearch_destroy(ts_conf);
		return -EAGAIN;
	}

	tm = kmalloc(sizeof(*tm), GFP_KERNEL);
	if (tm == NULL) {
		textsearch_destroy(ts_conf);
		return -ENOBUFS;
	}

	tm->from_offset = conf->from_offset;
	tm->to_offset   = conf->to_offset;
	tm->from_layer  = conf->from_layer;
	tm->to_layer    = conf->to_layer;
	tm->config      = ts_conf;

	m->datalen = sizeof(*tm);
	m->data = (unsigned long) tm;

	return 0;
}

static void em_text_destroy(struct tcf_ematch *m)
{
	if (EM_TEXT_PRIV(m) && EM_TEXT_PRIV(m)->config)
		textsearch_destroy(EM_TEXT_PRIV(m)->config);
}

static int em_text_dump(struct sk_buff *skb, struct tcf_ematch *m)
{
	struct text_match *tm = EM_TEXT_PRIV(m);
	struct tcf_em_text conf;

	strncpy(conf.algo, tm->config->ops->name, sizeof(conf.algo) - 1);
	conf.from_offset = tm->from_offset;
	conf.to_offset = tm->to_offset;
	conf.from_layer = tm->from_layer;
	conf.to_layer = tm->to_layer;
	conf.pattern_len = textsearch_get_pattern_len(tm->config);
	conf.pad = 0;

	if (nla_put_nohdr(skb, sizeof(conf), &conf) < 0)
		goto nla_put_failure;
	if (nla_append(skb, conf.pattern_len,
		       textsearch_get_pattern(tm->config)) < 0)
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

static struct tcf_ematch_ops em_text_ops = {
	.kind	  = TCF_EM_TEXT,
	.change	  = em_text_change,
	.match	  = em_text_match,
	.destroy  = em_text_destroy,
	.dump	  = em_text_dump,
	.owner	  = THIS_MODULE,
	.link	  = LIST_HEAD_INIT(em_text_ops.link)
};

static int __init init_em_text(void)
{
	return tcf_em_register(&em_text_ops);
}

static void __exit exit_em_text(void)
{
	tcf_em_unregister(&em_text_ops);
}

MODULE_LICENSE("GPL");

module_init(init_em_text);
module_exit(exit_em_text);

MODULE_ALIAS_TCF_EMATCH(TCF_EM_TEXT);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
d675c989 TG	2	/*
	3	* net/sched/em_text.c Textsearch ematch
	4	*
d675c989 TG	5	* Authors: Thomas Graf <tgraf@suug.ch>
	6	*/
	7
5a0e3ad6	8	#include <linux/slab.h>
d675c989 TG	9	#include <linux/module.h>
	10	#include <linux/types.h>
	11	#include <linux/kernel.h>
d675c989 TG	12	#include <linux/string.h>
	13	#include <linux/skbuff.h>
	14	#include <linux/textsearch.h>
	15	#include <linux/tc_ematch/tc_em_text.h>
	16	#include <net/pkt_cls.h>
	17
cc7ec456	18	struct text_match {
d675c989 TG	19	u16 from_offset;
	20	u16 to_offset;
	21	u8 from_layer;
	22	u8 to_layer;
	23	struct ts_config *config;
	24	};
	25
	26	#define EM_TEXT_PRIV(m) ((struct text_match *) (m)->data)
	27
	28	static int em_text_match(struct sk_buff skb, struct tcf_ematch m,
	29	struct tcf_pkt_info *info)
	30	{
	31	struct text_match *tm = EM_TEXT_PRIV(m);
	32	int from, to;
d675c989 TG	33
	34	from = tcf_get_base_ptr(skb, tm->from_layer) - skb->data;
	35	from += tm->from_offset;
	36
	37	to = tcf_get_base_ptr(skb, tm->to_layer) - skb->data;
	38	to += tm->to_offset;
	39
059a2440	40	return skb_find_text(skb, from, to, tm->config) != UINT_MAX;
d675c989 TG	41	}
d675c989 TG	42
82a470f1	43	static int em_text_change(struct net net, void data, int len,
d675c989 TG	44	struct tcf_ematch *m)
	45	{
	46	struct text_match *tm;
	47	struct tcf_em_text *conf = data;
	48	struct ts_config *ts_conf;
	49	int flags = 0;
	50
d675c989 TG	51	if (len < sizeof(conf) \|\| len < (sizeof(conf) + conf->pattern_len))
	52	return -EINVAL;
	53
	54	if (conf->from_layer > conf->to_layer)
	55	return -EINVAL;
	56
	57	if (conf->from_layer == conf->to_layer &&
	58	conf->from_offset > conf->to_offset)
	59	return -EINVAL;
	60
	61	retry:
	62	ts_conf = textsearch_prepare(conf->algo, (u8 ) conf + sizeof(conf),
	63	conf->pattern_len, GFP_KERNEL, flags);
	64
	65	if (flags & TS_AUTOLOAD)
	66	rtnl_lock();
	67
	68	if (IS_ERR(ts_conf)) {
	69	if (PTR_ERR(ts_conf) == -ENOENT && !(flags & TS_AUTOLOAD)) {
	70	rtnl_unlock();
	71	flags \|= TS_AUTOLOAD;
	72	goto retry;
	73	} else
	74	return PTR_ERR(ts_conf);
	75	} else if (flags & TS_AUTOLOAD) {
	76	textsearch_destroy(ts_conf);
	77	return -EAGAIN;
	78	}
	79
	80	tm = kmalloc(sizeof(*tm), GFP_KERNEL);
	81	if (tm == NULL) {
	82	textsearch_destroy(ts_conf);
	83	return -ENOBUFS;
	84	}
	85
	86	tm->from_offset = conf->from_offset;
	87	tm->to_offset = conf->to_offset;
	88	tm->from_layer = conf->from_layer;
	89	tm->to_layer = conf->to_layer;
	90	tm->config = ts_conf;
	91
	92	m->datalen = sizeof(*tm);
	93	m->data = (unsigned long) tm;
	94
	95	return 0;
	96	}
	97
82a470f1	98	static void em_text_destroy(struct tcf_ematch *m)
d675c989	99	{
5ec1cea0 TG	100	if (EM_TEXT_PRIV(m) && EM_TEXT_PRIV(m)->config)
5ec1cea0 TG	101	textsearch_destroy(EM_TEXT_PRIV(m)->config);
d675c989 TG	102	}
	103
	104	static int em_text_dump(struct sk_buff skb, struct tcf_ematch m)
	105	{
	106	struct text_match *tm = EM_TEXT_PRIV(m);
	107	struct tcf_em_text conf;
	108
	109	strncpy(conf.algo, tm->config->ops->name, sizeof(conf.algo) - 1);
	110	conf.from_offset = tm->from_offset;
	111	conf.to_offset = tm->to_offset;
	112	conf.from_layer = tm->from_layer;
	113	conf.to_layer = tm->to_layer;
	114	conf.pattern_len = textsearch_get_pattern_len(tm->config);
	115	conf.pad = 0;
	116
add93b61 PM	117	if (nla_put_nohdr(skb, sizeof(conf), &conf) < 0)
	118	goto nla_put_failure;
	119	if (nla_append(skb, conf.pattern_len,
	120	textsearch_get_pattern(tm->config)) < 0)
	121	goto nla_put_failure;
d675c989 TG	122	return 0;
d675c989 TG	123
add93b61	124	nla_put_failure:
d675c989	125	return -1;
10297b99	126	}
d675c989 TG	127
	128	static struct tcf_ematch_ops em_text_ops = {
	129	.kind = TCF_EM_TEXT,
	130	.change = em_text_change,
	131	.match = em_text_match,
	132	.destroy = em_text_destroy,
	133	.dump = em_text_dump,
	134	.owner = THIS_MODULE,
	135	.link = LIST_HEAD_INIT(em_text_ops.link)
	136	};
	137
	138	static int __init init_em_text(void)
	139	{
	140	return tcf_em_register(&em_text_ops);
	141	}
	142
10297b99	143	static void __exit exit_em_text(void)
d675c989 TG	144	{
	145	tcf_em_unregister(&em_text_ops);
	146	}
	147
	148	MODULE_LICENSE("GPL");
	149
	150	module_init(init_em_text);
	151	module_exit(exit_em_text);
db3d99c0 PM	152
db3d99c0 PM	153	MODULE_ALIAS_TCF_EMATCH(TCF_EM_TEXT);