| /* |
| * 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 <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 struct tcf_hashinfo pedit_hash_info; |
| |
| 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 tcf_common *pc; |
| 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; |
| |
| pc = tcf_hash_check(parm->index, a, bind, &pedit_hash_info); |
| if (!pc) { |
| if (!parm->nkeys) |
| return -EINVAL; |
| pc = tcf_hash_create(parm->index, est, a, sizeof(*p), bind, |
| &pedit_hash_info); |
| if (IS_ERR(pc)) |
| return PTR_ERR(pc); |
| p = to_pedit(pc); |
| keys = kmalloc(ksize, GFP_KERNEL); |
| if (keys == NULL) { |
| if (est) |
| gen_kill_estimator(&pc->tcfc_bstats, |
| &pc->tcfc_rate_est); |
| kfree_rcu(pc, tcfc_rcu); |
| return -ENOMEM; |
| } |
| ret = ACT_P_CREATED; |
| } else { |
| p = to_pedit(pc); |
| tcf_hash_release(pc, bind, &pedit_hash_info); |
| 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(pc, &pedit_hash_info); |
| return ret; |
| } |
| |
| static int tcf_pedit_cleanup(struct tc_action *a, int bind) |
| { |
| struct tcf_pedit *p = a->priv; |
| |
| if (p) { |
| struct tc_pedit_key *keys = p->tcfp_keys; |
| if (tcf_hash_release(&p->common, bind, &pedit_hash_info)) { |
| kfree(keys); |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| 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", |
| .hinfo = &pedit_hash_info, |
| .type = TCA_ACT_PEDIT, |
| .capab = TCA_CAP_NONE, |
| .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) |
| { |
| int err = tcf_hashinfo_init(&pedit_hash_info, PEDIT_TAB_MASK); |
| if (err) |
| return err; |
| return tcf_register_action(&act_pedit_ops); |
| } |
| |
| static void __exit pedit_cleanup_module(void) |
| { |
| tcf_hashinfo_destroy(&pedit_hash_info); |
| tcf_unregister_action(&act_pedit_ops); |
| } |
| |
| module_init(pedit_init_module); |
| module_exit(pedit_cleanup_module); |
| |