/*
* net/sched/pedit.c Generic packet editor
*
* 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: Jamal Hadi Salim (2002-4)
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <net/sock.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_pedit.h>
#include <net/tc_act/tc_pedit.h>
#define PEDIT_DEB 1
/* use generic hash table */
#define MY_TAB_SIZE 16
#define MY_TAB_MASK 15
static u32 idx_gen;
static struct tcf_pedit *tcf_pedit_ht[MY_TAB_SIZE];
static DEFINE_RWLOCK(pedit_lock);
#define tcf_st tcf_pedit
#define tc_st tc_pedit
#define tcf_t_lock pedit_lock
#define tcf_ht tcf_pedit_ht
#define CONFIG_NET_ACT_INIT 1
#include <net/pkt_act.h>
static int
tcf_pedit_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a,
int ovr, int bind)
{
struct rtattr *tb[TCA_PEDIT_MAX];
struct tc_pedit *parm;
int ret = 0;
struct tcf_pedit *p;
struct tc_pedit_key *keys = NULL;
int ksize;
if (rta == NULL || rtattr_parse_nested(tb, TCA_PEDIT_MAX, rta) < 0)
return -EINVAL;
if (tb[TCA_PEDIT_PARMS - 1] == NULL ||
RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm))
return -EINVAL;
parm = RTA_DATA(tb[TCA_PEDIT_PARMS-1]);
ksize = parm->nkeys * sizeof(struct tc_pedit_key);
if (RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm) + ksize)
return -EINVAL;
p = tcf_hash_check(parm->index, a, ovr, bind);
if (p == NULL) {
if (!parm->nkeys)
return -EINVAL;
p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind);
if (p == NULL)
return -ENOMEM;
keys = kmalloc(ksize, GFP_KERNEL);
if (keys == NULL) {
kfree(p);
return -ENOMEM;
}
ret = ACT_P_CREATED;
} else {
if (!ovr) {
tcf_hash_release(p, bind);
return -EEXIST;
}
if (p->nkeys && p->nkeys != parm->nkeys) {
keys = kmalloc(ksize, GFP_KERNEL);
if (keys == NULL)
return -ENOMEM;
}
}
spin_lock_bh(&p->lock);
p->flags = parm->flags;
p->action = parm->action;
if (keys) {
kfree(p->keys);
p->keys = keys;
p->nkeys = parm->nkeys;
}
memcpy(p->keys, parm->keys, ksize);
spin_unlock_bh(&p->lock);
if (ret == ACT_P_CREATED)
tcf_hash_insert(p);
return ret;
}
static int
tcf_pedit_cleanup(struct tc_action *a, int bind)
{
struct tcf_pedit *p = PRIV(a, pedit);
if (p != NULL) {
struct tc_pedit_key *keys = p->keys;
if (tcf_hash_release(p, bind)) {
kfree(keys);
return 1;
}
}
return 0;
}
static int
tcf_pedit(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res)
{
struct tcf_pedit *p = PRIV(a, pedit);
int i, munged = 0;
u8 *pptr;
if (!(skb->tc_verd & TC_OK2MUNGE)) {
/* should we set skb->cloned? */
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
return p->action;
}
}
pptr = skb->nh.raw;
spin_lock(&p->lock);
p->tm.lastuse = jiffies;
if (p->nkeys > 0) {
struct tc_pedit_key *tkey = p->keys;
for (i = p->nkeys; i > 0; i--, tkey++) {
u32 *ptr;
int offset = tkey->off;
if (tkey->offmask) {
if (skb->len > tkey->at) {
char *j = pptr + tkey->at;
offset += ((*j & tkey->offmask) >>
tkey->shift);
} else {
goto bad;
}
}
if (offset % 4) {
printk("offset must be on 32 bit boundaries\n");
goto bad;
}
if (skb->len < 0 || (offset > 0 && offset > skb->len)) {
printk("offset %d cant exceed pkt length %d\n",
offset, skb->len);
goto bad;
}
ptr = (u32 *)(pptr+offset);
/* just do it, baby */
*ptr = ((*ptr & tkey->mask) ^ tkey->val);
munged++;
}
if (munged)
skb->tc_verd = SET_TC_MUNGED(skb->tc_verd);
goto done;
} else {
printk("pedit BUG: index %d\n",p->index);
}
bad:
p->qstats.overlimits++;
done:
p->bstats.bytes += skb->len;
p->bstats.packets++;
spin_unlock(&p->lock);
return p->action;
}
static int
tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,int bind, int ref)
{
unsigned char *b = skb->tail;
struct tc_pedit *opt;
struct tcf_pedit *p = PRIV(a, pedit);
struct tcf_t t;
int s;
s = sizeof(*opt) + p->nkeys * sizeof(struct tc_pedit_key);
/* netlink spinlocks held above us - must use ATOMIC */
opt = kmalloc(s, GFP_ATOMIC);
if (opt == NULL)
return -ENOBUFS;
memset(opt, 0, s);
memcpy(opt->keys, p->keys, p->nkeys * sizeof(struct tc_pedit_key));
opt->index = p->index;
opt->nkeys = p->nkeys;
opt->flags = p->flags;
opt->action = p->action;
opt->refcnt = p->refcnt - ref;
opt->bindcnt = p->bindcnt - bind;
#ifdef PEDIT_DEB
{
/* Debug - get rid of later */
int i;
struct tc_pedit_key *key = opt->keys;
for (i=0; i<opt->nkeys; i++, key++) {
printk( "\n key #%d",i);
printk( " at %d: val %08x mask %08x",
(unsigned int)key->off,
(unsigned int)key->val,
(unsigned int)key->mask);
}
}
#endif
RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
t.install = jiffies_to_clock_t(jiffies - p->tm.install);
t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse);
t.expires = jiffies_to_clock_t(p->tm.expires);
RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
kfree(opt);
return skb->len;
rtattr_failure:
skb_trim(skb, b - skb->data);
kfree(opt);
return -1;
}
static
struct tc_action_ops act_pedit_ops = {
.kind = "pedit",
.type = TCA_ACT_PEDIT,
.capab = TCA_CAP_NONE,
.owner = THIS_MODULE,
.act = tcf_pedit,
.dump = tcf_pedit_dump,
.cleanup = tcf_pedit_cleanup,
.lookup = tcf_hash_search,
.init = tcf_pedit_init,
.walk = tcf_generic_walker
};
MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Generic Packet Editor actions");
MODULE_LICENSE("GPL");
static int __init
pedit_init_module(void)
{
return tcf_register_action(&act_pedit_ops);
}
static void __exit
pedit_cleanup_module(void)
{
tcf_unregister_action(&act_pedit_ops);
}
module_init(pedit_init_module);
module_exit(pedit_cleanup_module);
