Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * net/sched/em_text.c  Textsearch ematch

 *

 *              This program is free software; you can redistribute it and/or

 *              modify it under the terms of the GNU General Public License

 *              as published by the Free Software Foundation; either version

 *              2 of the License, or (at your option) any later version.

 *

 * Authors:     Thomas Graf <tgraf@suug.ch>

 */

#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;

        struct ts_state state;

        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, &state) != UINT_MAX;

}

static int em_text_change(struct tcf_proto *tp, 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_proto *tp, struct tcf_ematch *m)

{

        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;

        RTA_PUT_NOHDR(skb, sizeof(conf), &conf);

        RTA_APPEND(skb, conf.pattern_len, textsearch_get_pattern(tm->config));

        return 0;

rtattr_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);