diff options
Diffstat (limited to 'net/sched/act_pedit.c')
| -rw-r--r-- | net/sched/act_pedit.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c new file mode 100644 index 000000000..59649d588 --- /dev/null +++ b/net/sched/act_pedit.c @@ -0,0 +1,243 @@ +/* + * net/sched/act_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 <linux/types.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/skbuff.h> +#include <linux/rtnetlink.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <net/netlink.h> +#include <net/pkt_sched.h> +#include <linux/tc_act/tc_pedit.h> +#include <net/tc_act/tc_pedit.h> + +#define PEDIT_TAB_MASK 15 + +static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = { + [TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) }, +}; + +static int tcf_pedit_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action *a, + int ovr, int bind) +{ + struct nlattr *tb[TCA_PEDIT_MAX + 1]; + struct tc_pedit *parm; + int ret = 0, err; + struct tcf_pedit *p; + struct tc_pedit_key *keys = NULL; + int ksize; + + if (nla == NULL) + return -EINVAL; + + err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy); + if (err < 0) + return err; + + if (tb[TCA_PEDIT_PARMS] == NULL) + return -EINVAL; + parm = nla_data(tb[TCA_PEDIT_PARMS]); + ksize = parm->nkeys * sizeof(struct tc_pedit_key); + if (nla_len(tb[TCA_PEDIT_PARMS]) < sizeof(*parm) + ksize) + return -EINVAL; + + if (!tcf_hash_check(parm->index, a, bind)) { + if (!parm->nkeys) + return -EINVAL; + ret = tcf_hash_create(parm->index, est, a, sizeof(*p), bind); + if (ret) + return ret; + p = to_pedit(a); + keys = kmalloc(ksize, GFP_KERNEL); + if (keys == NULL) { + tcf_hash_cleanup(a, est); + return -ENOMEM; + } + ret = ACT_P_CREATED; + } else { + p = to_pedit(a); + tcf_hash_release(a, bind); + if (bind) + return 0; + if (!ovr) + return -EEXIST; + + if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) { + keys = kmalloc(ksize, GFP_KERNEL); + if (keys == NULL) + return -ENOMEM; + } + } + + spin_lock_bh(&p->tcf_lock); + p->tcfp_flags = parm->flags; + p->tcf_action = parm->action; + if (keys) { + kfree(p->tcfp_keys); + p->tcfp_keys = keys; + p->tcfp_nkeys = parm->nkeys; + } + memcpy(p->tcfp_keys, parm->keys, ksize); + spin_unlock_bh(&p->tcf_lock); + if (ret == ACT_P_CREATED) + tcf_hash_insert(a); + return ret; +} + +static void tcf_pedit_cleanup(struct tc_action *a, int bind) +{ + struct tcf_pedit *p = a->priv; + struct tc_pedit_key *keys = p->tcfp_keys; + kfree(keys); +} + +static int tcf_pedit(struct sk_buff *skb, const struct tc_action *a, + struct tcf_result *res) +{ + struct tcf_pedit *p = a->priv; + int i, munged = 0; + unsigned int off; + + if (skb_unclone(skb, GFP_ATOMIC)) + return p->tcf_action; + + off = skb_network_offset(skb); + + spin_lock(&p->tcf_lock); + + p->tcf_tm.lastuse = jiffies; + + if (p->tcfp_nkeys > 0) { + struct tc_pedit_key *tkey = p->tcfp_keys; + + for (i = p->tcfp_nkeys; i > 0; i--, tkey++) { + u32 *ptr, _data; + int offset = tkey->off; + + if (tkey->offmask) { + char *d, _d; + + d = skb_header_pointer(skb, off + tkey->at, 1, + &_d); + if (!d) + goto bad; + offset += (*d & tkey->offmask) >> tkey->shift; + } + + if (offset % 4) { + pr_info("tc filter pedit" + " offset must be on 32 bit boundaries\n"); + goto bad; + } + if (offset > 0 && offset > skb->len) { + pr_info("tc filter pedit" + " offset %d can't exceed pkt length %d\n", + offset, skb->len); + goto bad; + } + + ptr = skb_header_pointer(skb, off + offset, 4, &_data); + if (!ptr) + goto bad; + /* just do it, baby */ + *ptr = ((*ptr & tkey->mask) ^ tkey->val); + if (ptr == &_data) + skb_store_bits(skb, off + offset, ptr, 4); + munged++; + } + + if (munged) + skb->tc_verd = SET_TC_MUNGED(skb->tc_verd); + goto done; + } else + WARN(1, "pedit BUG: index %d\n", p->tcf_index); + +bad: + p->tcf_qstats.overlimits++; +done: + bstats_update(&p->tcf_bstats, skb); + spin_unlock(&p->tcf_lock); + return p->tcf_action; +} + +static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a, + int bind, int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_pedit *p = a->priv; + struct tc_pedit *opt; + struct tcf_t t; + int s; + + s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key); + + /* netlink spinlocks held above us - must use ATOMIC */ + opt = kzalloc(s, GFP_ATOMIC); + if (unlikely(!opt)) + return -ENOBUFS; + + memcpy(opt->keys, p->tcfp_keys, + p->tcfp_nkeys * sizeof(struct tc_pedit_key)); + opt->index = p->tcf_index; + opt->nkeys = p->tcfp_nkeys; + opt->flags = p->tcfp_flags; + opt->action = p->tcf_action; + opt->refcnt = p->tcf_refcnt - ref; + opt->bindcnt = p->tcf_bindcnt - bind; + + if (nla_put(skb, TCA_PEDIT_PARMS, s, opt)) + goto nla_put_failure; + t.install = jiffies_to_clock_t(jiffies - p->tcf_tm.install); + t.lastuse = jiffies_to_clock_t(jiffies - p->tcf_tm.lastuse); + t.expires = jiffies_to_clock_t(p->tcf_tm.expires); + if (nla_put(skb, TCA_PEDIT_TM, sizeof(t), &t)) + goto nla_put_failure; + kfree(opt); + return skb->len; + +nla_put_failure: + nlmsg_trim(skb, b); + kfree(opt); + return -1; +} + +static struct tc_action_ops act_pedit_ops = { + .kind = "pedit", + .type = TCA_ACT_PEDIT, + .owner = THIS_MODULE, + .act = tcf_pedit, + .dump = tcf_pedit_dump, + .cleanup = tcf_pedit_cleanup, + .init = tcf_pedit_init, +}; + +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, PEDIT_TAB_MASK); +} + +static void __exit pedit_cleanup_module(void) +{ + tcf_unregister_action(&act_pedit_ops); +} + +module_init(pedit_init_module); +module_exit(pedit_cleanup_module); + |