1 files changed, 260 insertions, 0 deletions
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
new file mode 100644
index 0000000..d5f4e34
--- /dev/null
+++ b/net/sched/act_pedit.c
@@ -0,0 +1,260 @@
+/*
+ * 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 <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_common *tcf_pedit_ht[PEDIT_TAB_MASK + 1];
+static u32 pedit_idx_gen;
+static DEFINE_RWLOCK(pedit_lock);
+
+static struct tcf_hashinfo pedit_hash_info = {
+	.htab	=	tcf_pedit_ht,
+	.hmask	=	PEDIT_TAB_MASK,
+	.lock	=	&pedit_lock,
+};
+
+static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
+	[TCA_PEDIT_PARMS]	= { .len = sizeof(struct tcf_pedit) },
+};
+
+static int tcf_pedit_init(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_idx_gen, &pedit_hash_info);
+		if (unlikely(!pc))
+			return -ENOMEM;
+		p = to_pedit(pc);
+		keys = kmalloc(ksize, GFP_KERNEL);
+		if (keys == NULL) {
+			kfree(pc);
+			return -ENOMEM;
+		}
+		ret = ACT_P_CREATED;
+	} else {
+		p = to_pedit(pc);
+		if (!ovr) {
+			tcf_hash_release(pc, bind, &pedit_hash_info);
+			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, struct tc_action *a,
+		     struct tcf_result *res)
+{
+	struct tcf_pedit *p = a->priv;
+	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->tcf_action;
+		}
+	}
+
+	pptr = skb_network_header(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;
+			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 (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->tcf_index);
+	}
+
+bad:
+	p->tcf_qstats.overlimits++;
+done:
+	p->tcf_bstats.bytes += qdisc_pkt_len(skb);
+	p->tcf_bstats.packets++;
+	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;
+
+	NLA_PUT(skb, TCA_PEDIT_PARMS, s, opt);
+	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);
+	NLA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t);
+	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,
+	.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);
+