[linux.git] / net / sched / act_pedit.c

/*
 * 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>
#include <uapi/linux/tc_act/tc_pedit.h>

static unsigned int pedit_net_id;
static struct tc_action_ops act_pedit_ops;

static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
	[TCA_PEDIT_PARMS]	= { .len = sizeof(struct tc_pedit) },
	[TCA_PEDIT_KEYS_EX]   = { .type = NLA_NESTED },
};

static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
	[TCA_PEDIT_KEY_EX_HTYPE]  = { .type = NLA_U16 },
	[TCA_PEDIT_KEY_EX_CMD]	  = { .type = NLA_U16 },
};

static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
							u8 n)
{
	struct tcf_pedit_key_ex *keys_ex;
	struct tcf_pedit_key_ex *k;
	const struct nlattr *ka;
	int err = -EINVAL;
	int rem;

	if (!nla || !n)
		return NULL;

	keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
	if (!keys_ex)
		return ERR_PTR(-ENOMEM);

	k = keys_ex;

	nla_for_each_nested(ka, nla, rem) {
		struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];

		if (!n) {
			err = -EINVAL;
			goto err_out;
		}
		n--;

		if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
			err = -EINVAL;
			goto err_out;
		}

		err = nla_parse_nested(tb, TCA_PEDIT_KEY_EX_MAX, ka,
				       pedit_key_ex_policy, NULL);
		if (err)
			goto err_out;

		if (!tb[TCA_PEDIT_KEY_EX_HTYPE] ||
		    !tb[TCA_PEDIT_KEY_EX_CMD]) {
			err = -EINVAL;
			goto err_out;
		}

		k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
		k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);

		if (k->htype > TCA_PEDIT_HDR_TYPE_MAX ||
		    k->cmd > TCA_PEDIT_CMD_MAX) {
			err = -EINVAL;
			goto err_out;
		}

		k++;
	}

	if (n) {
		err = -EINVAL;
		goto err_out;
	}

	return keys_ex;

err_out:
	kfree(keys_ex);
	return ERR_PTR(err);
}

static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
				 struct tcf_pedit_key_ex *keys_ex, int n)
{
	struct nlattr *keys_start = nla_nest_start(skb, TCA_PEDIT_KEYS_EX);

	if (!keys_start)
		goto nla_failure;
	for (; n > 0; n--) {
		struct nlattr *key_start;

		key_start = nla_nest_start(skb, TCA_PEDIT_KEY_EX);
		if (!key_start)
			goto nla_failure;

		if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
		    nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
			goto nla_failure;

		nla_nest_end(skb, key_start);

		keys_ex++;
	}

	nla_nest_end(skb, keys_start);

	return 0;
nla_failure:
	nla_nest_cancel(skb, keys_start);
	return -EINVAL;
}

static int tcf_pedit_init(struct net *net, struct nlattr *nla,
			  struct nlattr *est, struct tc_action **a,
			  int ovr, int bind, bool rtnl_held,
			  struct netlink_ext_ack *extack)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	struct nlattr *tb[TCA_PEDIT_MAX + 1];
	struct tc_pedit_key *keys = NULL;
	struct tcf_pedit_key_ex *keys_ex;
	struct tc_pedit *parm;
	struct nlattr *pattr;
	struct tcf_pedit *p;
	int ret = 0, err;
	int ksize;

	if (!nla) {
		NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
		return -EINVAL;
	}

	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy, NULL);
	if (err < 0)
		return err;

	pattr = tb[TCA_PEDIT_PARMS];
	if (!pattr)
		pattr = tb[TCA_PEDIT_PARMS_EX];
	if (!pattr) {
		NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
		return -EINVAL;
	}

	parm = nla_data(pattr);
	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	if (nla_len(pattr) < sizeof(*parm) + ksize) {
		NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
		return -EINVAL;
	}

	keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
	if (IS_ERR(keys_ex))
		return PTR_ERR(keys_ex);

	err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
	if (!err) {
		if (!parm->nkeys) {
			tcf_idr_cleanup(tn, parm->index);
			NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
			ret = -EINVAL;
			goto out_free;
		}
		ret = tcf_idr_create(tn, parm->index, est, a,
				     &act_pedit_ops, bind, false);
		if (ret) {
			tcf_idr_cleanup(tn, parm->index);
			goto out_free;
		}
		ret = ACT_P_CREATED;
	} else if (err > 0) {
		if (bind)
			goto out_free;
		if (!ovr) {
			ret = -EEXIST;
			goto out_release;
		}
	} else {
		ret = err;
		goto out_free;
	}

	p = to_pedit(*a);
	spin_lock_bh(&p->tcf_lock);

	if (ret == ACT_P_CREATED ||
	    (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
		keys = kmalloc(ksize, GFP_ATOMIC);
		if (!keys) {
			spin_unlock_bh(&p->tcf_lock);
			ret = -ENOMEM;
			goto out_release;
		}
		kfree(p->tcfp_keys);
		p->tcfp_keys = keys;
		p->tcfp_nkeys = parm->nkeys;
	}
	memcpy(p->tcfp_keys, parm->keys, ksize);

	p->tcfp_flags = parm->flags;
	p->tcf_action = parm->action;

	kfree(p->tcfp_keys_ex);
	p->tcfp_keys_ex = keys_ex;

	spin_unlock_bh(&p->tcf_lock);
	if (ret == ACT_P_CREATED)
		tcf_idr_insert(tn, *a);
	return ret;

out_release:
	tcf_idr_release(*a, bind);
out_free:
	kfree(keys_ex);
	return ret;

}

static void tcf_pedit_cleanup(struct tc_action *a)
{
	struct tcf_pedit *p = to_pedit(a);
	struct tc_pedit_key *keys = p->tcfp_keys;

	kfree(keys);
	kfree(p->tcfp_keys_ex);
}

static bool offset_valid(struct sk_buff *skb, int offset)
{
	if (offset > 0 && offset > skb->len)
		return false;

	if  (offset < 0 && -offset > skb_headroom(skb))
		return false;

	return true;
}

static int pedit_skb_hdr_offset(struct sk_buff *skb,
				enum pedit_header_type htype, int *hoffset)
{
	int ret = -EINVAL;

	switch (htype) {
	case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
		if (skb_mac_header_was_set(skb)) {
			*hoffset = skb_mac_offset(skb);
			ret = 0;
		}
		break;
	case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
		*hoffset = skb_network_offset(skb);
		ret = 0;
		break;
	case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
	case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
		if (skb_transport_header_was_set(skb)) {
			*hoffset = skb_transport_offset(skb);
			ret = 0;
		}
		break;
	default:
		ret = -EINVAL;
		break;
	}

	return ret;
}

static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a,
			 struct tcf_result *res)
{
	struct tcf_pedit *p = to_pedit(a);
	int i;

	if (skb_unclone(skb, GFP_ATOMIC))
		return p->tcf_action;

	spin_lock(&p->tcf_lock);

	tcf_lastuse_update(&p->tcf_tm);

	if (p->tcfp_nkeys > 0) {
		struct tc_pedit_key *tkey = p->tcfp_keys;
		struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
		enum pedit_header_type htype =
			TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
		enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;

		for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
			u32 *ptr, hdata;
			int offset = tkey->off;
			int hoffset;
			u32 val;
			int rc;

			if (tkey_ex) {
				htype = tkey_ex->htype;
				cmd = tkey_ex->cmd;

				tkey_ex++;
			}

			rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
			if (rc) {
				pr_info("tc action pedit bad header type specified (0x%x)\n",
					htype);
				goto bad;
			}

			if (tkey->offmask) {
				u8 *d, _d;

				if (!offset_valid(skb, hoffset + tkey->at)) {
					pr_info("tc action pedit 'at' offset %d out of bounds\n",
						hoffset + tkey->at);
					goto bad;
				}
				d = skb_header_pointer(skb, hoffset + tkey->at,
						       sizeof(_d), &_d);
				if (!d)
					goto bad;
				offset += (*d & tkey->offmask) >> tkey->shift;
			}

			if (offset % 4) {
				pr_info("tc action pedit offset must be on 32 bit boundaries\n");
				goto bad;
			}

			if (!offset_valid(skb, hoffset + offset)) {
				pr_info("tc action pedit offset %d out of bounds\n",
					hoffset + offset);
				goto bad;
			}

			ptr = skb_header_pointer(skb, hoffset + offset,
						 sizeof(hdata), &hdata);
			if (!ptr)
				goto bad;
			/* just do it, baby */
			switch (cmd) {
			case TCA_PEDIT_KEY_EX_CMD_SET:
				val = tkey->val;
				break;
			case TCA_PEDIT_KEY_EX_CMD_ADD:
				val = (*ptr + tkey->val) & ~tkey->mask;
				break;
			default:
				pr_info("tc action pedit bad command (%d)\n",
					cmd);
				goto bad;
			}

			*ptr = ((*ptr & tkey->mask) ^ val);
			if (ptr == &hdata)
				skb_store_bits(skb, hoffset + offset, ptr, 4);
		}

		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 = to_pedit(a);
	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;

	spin_lock_bh(&p->tcf_lock);
	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 = refcount_read(&p->tcf_refcnt) - ref;
	opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;

	if (p->tcfp_keys_ex) {
		if (tcf_pedit_key_ex_dump(skb,
					  p->tcfp_keys_ex,
					  p->tcfp_nkeys))
			goto nla_put_failure;

		if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
			goto nla_put_failure;
	} else {
		if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
			goto nla_put_failure;
	}

	tcf_tm_dump(&t, &p->tcf_tm);
	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
		goto nla_put_failure;
	spin_unlock_bh(&p->tcf_lock);

	kfree(opt);
	return skb->len;

nla_put_failure:
	spin_unlock_bh(&p->tcf_lock);
	nlmsg_trim(skb, b);
	kfree(opt);
	return -1;
}

static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
			    struct netlink_callback *cb, int type,
			    const struct tc_action_ops *ops,
			    struct netlink_ext_ack *extack)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
}

static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tcf_idr_search(tn, a, index);
}

static struct tc_action_ops act_pedit_ops = {
	.kind		=	"pedit",
	.type		=	TCA_ACT_PEDIT,
	.owner		=	THIS_MODULE,
	.act		=	tcf_pedit_act,
	.dump		=	tcf_pedit_dump,
	.cleanup	=	tcf_pedit_cleanup,
	.init		=	tcf_pedit_init,
	.walk		=	tcf_pedit_walker,
	.lookup		=	tcf_pedit_search,
	.size		=	sizeof(struct tcf_pedit),
};

static __net_init int pedit_init_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	return tc_action_net_init(tn, &act_pedit_ops);
}

static void __net_exit pedit_exit_net(struct list_head *net_list)
{
	tc_action_net_exit(net_list, pedit_net_id);
}

static struct pernet_operations pedit_net_ops = {
	.init = pedit_init_net,
	.exit_batch = pedit_exit_net,
	.id   = &pedit_net_id,
	.size = sizeof(struct tc_action_net),
};

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_net_ops);
}

static void __exit pedit_cleanup_module(void)
{
	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
}

module_init(pedit_init_module);
module_exit(pedit_cleanup_module);
Commit	Line	Data
1da177e4	1	/*
0c6965dd	2	* net/sched/act_pedit.c Generic packet editor
1da177e4 LT	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation; either version
	7	* 2 of the License, or (at your option) any later version.
	8	*
	9	* Authors: Jamal Hadi Salim (2002-4)
	10	*/
	11
1da177e4 LT	12	#include <linux/types.h>
1da177e4 LT	13	#include <linux/kernel.h>
1da177e4	14	#include <linux/string.h>
1da177e4	15	#include <linux/errno.h>
1da177e4 LT	16	#include <linux/skbuff.h>
	17	#include <linux/rtnetlink.h>
	18	#include <linux/module.h>
	19	#include <linux/init.h>
5a0e3ad6	20	#include <linux/slab.h>
dc5fc579	21	#include <net/netlink.h>
1da177e4 LT	22	#include <net/pkt_sched.h>
	23	#include <linux/tc_act/tc_pedit.h>
	24	#include <net/tc_act/tc_pedit.h>
71d0ed70	25	#include <uapi/linux/tc_act/tc_pedit.h>
1da177e4	26
c7d03a00	27	static unsigned int pedit_net_id;
a85a970a	28	static struct tc_action_ops act_pedit_ops;
ddf97ccd	29
53b2bf3f	30	static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
53f7e35f	31	[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
71d0ed70	32	[TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
53b2bf3f PM	33	};
53b2bf3f PM	34
71d0ed70 AV	35	static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
71d0ed70 AV	36	[TCA_PEDIT_KEY_EX_HTYPE] = { .type = NLA_U16 },
853a14ba	37	[TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 },
71d0ed70 AV	38	};
	39
	40	static struct tcf_pedit_key_ex tcf_pedit_keys_ex_parse(struct nlattr nla,
	41	u8 n)
	42	{
	43	struct tcf_pedit_key_ex *keys_ex;
	44	struct tcf_pedit_key_ex *k;
	45	const struct nlattr *ka;
	46	int err = -EINVAL;
	47	int rem;
	48
	49	if (!nla \|\| !n)
	50	return NULL;
	51
	52	keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
	53	if (!keys_ex)
	54	return ERR_PTR(-ENOMEM);
	55
	56	k = keys_ex;
	57
	58	nla_for_each_nested(ka, nla, rem) {
	59	struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
	60
	61	if (!n) {
	62	err = -EINVAL;
	63	goto err_out;
	64	}
	65	n--;
	66
	67	if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
	68	err = -EINVAL;
	69	goto err_out;
	70	}
	71
	72	err = nla_parse_nested(tb, TCA_PEDIT_KEY_EX_MAX, ka,
fceb6435	73	pedit_key_ex_policy, NULL);
71d0ed70 AV	74	if (err)
	75	goto err_out;
	76
853a14ba AV	77	if (!tb[TCA_PEDIT_KEY_EX_HTYPE] \|\|
853a14ba AV	78	!tb[TCA_PEDIT_KEY_EX_CMD]) {
71d0ed70 AV	79	err = -EINVAL;
	80	goto err_out;
	81	}
	82
	83	k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
853a14ba	84	k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
71d0ed70	85
853a14ba AV	86	if (k->htype > TCA_PEDIT_HDR_TYPE_MAX \|\|
853a14ba AV	87	k->cmd > TCA_PEDIT_CMD_MAX) {
71d0ed70 AV	88	err = -EINVAL;
	89	goto err_out;
	90	}
	91
	92	k++;
	93	}
	94
c4f65b09 DC	95	if (n) {
c4f65b09 DC	96	err = -EINVAL;
71d0ed70	97	goto err_out;
c4f65b09	98	}
71d0ed70 AV	99
	100	return keys_ex;
	101
	102	err_out:
	103	kfree(keys_ex);
	104	return ERR_PTR(err);
	105	}
	106
	107	static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
	108	struct tcf_pedit_key_ex *keys_ex, int n)
	109	{
	110	struct nlattr *keys_start = nla_nest_start(skb, TCA_PEDIT_KEYS_EX);
	111
85eb9af1 DC	112	if (!keys_start)
85eb9af1 DC	113	goto nla_failure;
71d0ed70 AV	114	for (; n > 0; n--) {
	115	struct nlattr *key_start;
	116
	117	key_start = nla_nest_start(skb, TCA_PEDIT_KEY_EX);
85eb9af1 DC	118	if (!key_start)
85eb9af1 DC	119	goto nla_failure;
71d0ed70	120
853a14ba	121	if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) \|\|
85eb9af1 DC	122	nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
85eb9af1 DC	123	goto nla_failure;
71d0ed70 AV	124
	125	nla_nest_end(skb, key_start);
	126
	127	keys_ex++;
	128	}
	129
	130	nla_nest_end(skb, keys_start);
	131
	132	return 0;
85eb9af1 DC	133	nla_failure:
	134	nla_nest_cancel(skb, keys_start);
	135	return -EINVAL;
71d0ed70 AV	136	}
71d0ed70 AV	137
c1b52739	138	static int tcf_pedit_init(struct net net, struct nlattr nla,
a85a970a	139	struct nlattr est, struct tc_action *a,
789871bb VB	140	int ovr, int bind, bool rtnl_held,
789871bb VB	141	struct netlink_ext_ack *extack)
1da177e4	142	{
ddf97ccd	143	struct tc_action_net *tn = net_generic(net, pedit_net_id);
7ba699c6	144	struct nlattr *tb[TCA_PEDIT_MAX + 1];
1da177e4	145	struct tc_pedit_key *keys = NULL;
71d0ed70	146	struct tcf_pedit_key_ex *keys_ex;
80f0f574 RM	147	struct tc_pedit *parm;
	148	struct nlattr *pattr;
	149	struct tcf_pedit *p;
	150	int ret = 0, err;
1da177e4 LT	151	int ksize;
1da177e4 LT	152
9868c0b2 RM	153	if (!nla) {
9868c0b2 RM	154	NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
1da177e4	155	return -EINVAL;
9868c0b2	156	}
1da177e4	157
fceb6435	158	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy, NULL);
cee63723 PM	159	if (err < 0)
	160	return err;
	161
71d0ed70 AV	162	pattr = tb[TCA_PEDIT_PARMS];
	163	if (!pattr)
	164	pattr = tb[TCA_PEDIT_PARMS_EX];
9868c0b2 RM	165	if (!pattr) {
9868c0b2 RM	166	NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
1da177e4	167	return -EINVAL;
9868c0b2	168	}
71d0ed70 AV	169
71d0ed70 AV	170	parm = nla_data(pattr);
1da177e4	171	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
9868c0b2 RM	172	if (nla_len(pattr) < sizeof(*parm) + ksize) {
9868c0b2 RM	173	NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
1da177e4	174	return -EINVAL;
9868c0b2	175	}
1da177e4	176
71d0ed70 AV	177	keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
	178	if (IS_ERR(keys_ex))
	179	return PTR_ERR(keys_ex);
	180
0190c1d4 VB	181	err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
0190c1d4 VB	182	if (!err) {
9868c0b2	183	if (!parm->nkeys) {
0190c1d4	184	tcf_idr_cleanup(tn, parm->index);
9868c0b2	185	NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
30e99ed6 WY	186	ret = -EINVAL;
30e99ed6 WY	187	goto out_free;
9868c0b2	188	}
65a206c0 CM	189	ret = tcf_idr_create(tn, parm->index, est, a,
65a206c0 CM	190	&act_pedit_ops, bind, false);
0190c1d4 VB	191	if (ret) {
0190c1d4 VB	192	tcf_idr_cleanup(tn, parm->index);
30e99ed6	193	goto out_free;
0190c1d4	194	}
1da177e4	195	ret = ACT_P_CREATED;
0190c1d4	196	} else if (err > 0) {
1a29321e	197	if (bind)
30e99ed6	198	goto out_free;
30e99ed6 WY	199	if (!ovr) {
30e99ed6 WY	200	ret = -EEXIST;
67b0c1a3	201	goto out_release;
1da177e4	202	}
0190c1d4	203	} else {
19ab6910 DC	204	ret = err;
19ab6910 DC	205	goto out_free;
1da177e4 LT	206	}
1da177e4 LT	207
67b0c1a3	208	p = to_pedit(*a);
e9ce1cd3	209	spin_lock_bh(&p->tcf_lock);
67b0c1a3 VB	210
	211	if (ret == ACT_P_CREATED \|\|
	212	(p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
	213	keys = kmalloc(ksize, GFP_ATOMIC);
	214	if (!keys) {
	215	spin_unlock_bh(&p->tcf_lock);
	216	ret = -ENOMEM;
	217	goto out_release;
	218	}
e9ce1cd3 DM	219	kfree(p->tcfp_keys);
	220	p->tcfp_keys = keys;
	221	p->tcfp_nkeys = parm->nkeys;
1da177e4	222	}
e9ce1cd3	223	memcpy(p->tcfp_keys, parm->keys, ksize);
71d0ed70	224
67b0c1a3 VB	225	p->tcfp_flags = parm->flags;
	226	p->tcf_action = parm->action;
	227
71d0ed70 AV	228	kfree(p->tcfp_keys_ex);
	229	p->tcfp_keys_ex = keys_ex;
	230
e9ce1cd3	231	spin_unlock_bh(&p->tcf_lock);
1da177e4	232	if (ret == ACT_P_CREATED)
65a206c0	233	tcf_idr_insert(tn, *a);
1da177e4	234	return ret;
67b0c1a3 VB	235
	236	out_release:
	237	tcf_idr_release(*a, bind);
30e99ed6 WY	238	out_free:
	239	kfree(keys_ex);
	240	return ret;
	241
1da177e4 LT	242	}
1da177e4 LT	243
9a63b255	244	static void tcf_pedit_cleanup(struct tc_action *a)
1da177e4	245	{
a85a970a	246	struct tcf_pedit *p = to_pedit(a);
a5b5c958	247	struct tc_pedit_key *keys = p->tcfp_keys;
80f0f574	248
a5b5c958	249	kfree(keys);
71d0ed70	250	kfree(p->tcfp_keys_ex);
1da177e4 LT	251	}
1da177e4 LT	252
95c2027b AV	253	static bool offset_valid(struct sk_buff *skb, int offset)
	254	{
	255	if (offset > 0 && offset > skb->len)
	256	return false;
	257
	258	if (offset < 0 && -offset > skb_headroom(skb))
	259	return false;
	260
	261	return true;
	262	}
	263
71d0ed70 AV	264	static int pedit_skb_hdr_offset(struct sk_buff *skb,
	265	enum pedit_header_type htype, int *hoffset)
	266	{
	267	int ret = -EINVAL;
	268
	269	switch (htype) {
	270	case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
	271	if (skb_mac_header_was_set(skb)) {
	272	*hoffset = skb_mac_offset(skb);
	273	ret = 0;
	274	}
	275	break;
	276	case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
	277	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
	278	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
	279	*hoffset = skb_network_offset(skb);
	280	ret = 0;
	281	break;
	282	case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
	283	case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
	284	if (skb_transport_header_was_set(skb)) {
	285	*hoffset = skb_transport_offset(skb);
	286	ret = 0;
	287	}
	288	break;
	289	default:
	290	ret = -EINVAL;
	291	break;
0a80848e	292	}
71d0ed70 AV	293
	294	return ret;
	295	}
	296
6a2b401c JHS	297	static int tcf_pedit_act(struct sk_buff skb, const struct tc_action a,
6a2b401c JHS	298	struct tcf_result *res)
1da177e4	299	{
a85a970a	300	struct tcf_pedit *p = to_pedit(a);
4749c3ef	301	int i;
1da177e4	302
14bbd6a5	303	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	304	return p->tcf_action;
1da177e4	305
e9ce1cd3	306	spin_lock(&p->tcf_lock);
1da177e4	307
9c4a4e48	308	tcf_lastuse_update(&p->tcf_tm);
1da177e4	309
e9ce1cd3 DM	310	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	311	struct tc_pedit_key *tkey = p->tcfp_keys;
71d0ed70	312	struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
80f0f574 RM	313	enum pedit_header_type htype =
80f0f574 RM	314	TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
853a14ba	315	enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
1da177e4	316
e9ce1cd3	317	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
544377cd	318	u32 *ptr, hdata;
1da177e4	319	int offset = tkey->off;
71d0ed70	320	int hoffset;
853a14ba	321	u32 val;
71d0ed70 AV	322	int rc;
	323
	324	if (tkey_ex) {
	325	htype = tkey_ex->htype;
853a14ba AV	326	cmd = tkey_ex->cmd;
853a14ba AV	327
71d0ed70 AV	328	tkey_ex++;
	329	}
	330
	331	rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
	332	if (rc) {
95b0d2dc	333	pr_info("tc action pedit bad header type specified (0x%x)\n",
71d0ed70 AV	334	htype);
	335	goto bad;
	336	}
1da177e4 LT	337
1da177e4 LT	338	if (tkey->offmask) {
43052741	339	u8 *d, _d;
db2c2417	340
71d0ed70	341	if (!offset_valid(skb, hoffset + tkey->at)) {
95b0d2dc	342	pr_info("tc action pedit 'at' offset %d out of bounds\n",
71d0ed70	343	hoffset + tkey->at);
95c2027b AV	344	goto bad;
95c2027b AV	345	}
80f0f574	346	d = skb_header_pointer(skb, hoffset + tkey->at,
6ff7586e	347	sizeof(_d), &_d);
db2c2417	348	if (!d)
1da177e4	349	goto bad;
db2c2417	350	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	351	}
	352
	353	if (offset % 4) {
95b0d2dc	354	pr_info("tc action pedit offset must be on 32 bit boundaries\n");
1da177e4 LT	355	goto bad;
1da177e4 LT	356	}
95c2027b	357
71d0ed70	358	if (!offset_valid(skb, hoffset + offset)) {
95b0d2dc	359	pr_info("tc action pedit offset %d out of bounds\n",
71d0ed70	360	hoffset + offset);
1da177e4 LT	361	goto bad;
	362	}
	363
80f0f574	364	ptr = skb_header_pointer(skb, hoffset + offset,
6ff7586e	365	sizeof(hdata), &hdata);
db2c2417 CG	366	if (!ptr)
db2c2417 CG	367	goto bad;
1da177e4	368	/* just do it, baby */
853a14ba AV	369	switch (cmd) {
	370	case TCA_PEDIT_KEY_EX_CMD_SET:
	371	val = tkey->val;
	372	break;
	373	case TCA_PEDIT_KEY_EX_CMD_ADD:
	374	val = (*ptr + tkey->val) & ~tkey->mask;
	375	break;
	376	default:
95b0d2dc	377	pr_info("tc action pedit bad command (%d)\n",
853a14ba AV	378	cmd);
	379	goto bad;
	380	}
	381
	382	ptr = ((ptr & tkey->mask) ^ val);
544377cd	383	if (ptr == &hdata)
71d0ed70	384	skb_store_bits(skb, hoffset + offset, ptr, 4);
1da177e4	385	}
10297b99	386
1da177e4	387	goto done;
80f0f574	388	} else {
6ff9c364	389	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
80f0f574	390	}
1da177e4 LT	391
1da177e4 LT	392	bad:
e9ce1cd3	393	p->tcf_qstats.overlimits++;
1da177e4	394	done:
bfe0d029	395	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	396	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	397	return p->tcf_action;
1da177e4 LT	398	}
1da177e4 LT	399
e9ce1cd3 DM	400	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	401	int bind, int ref)
1da177e4	402	{
27a884dc	403	unsigned char *b = skb_tail_pointer(skb);
a85a970a	404	struct tcf_pedit *p = to_pedit(a);
1da177e4	405	struct tc_pedit *opt;
1da177e4	406	struct tcf_t t;
10297b99 YH	407	int s;
10297b99 YH	408
e9ce1cd3	409	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	410
1da177e4 LT	411	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	412	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	413	if (unlikely(!opt))
1da177e4	414	return -ENOBUFS;
1da177e4	415
67b0c1a3	416	spin_lock_bh(&p->tcf_lock);
e9ce1cd3 DM	417	memcpy(opt->keys, p->tcfp_keys,
	418	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	419	opt->index = p->tcf_index;
	420	opt->nkeys = p->tcfp_nkeys;
	421	opt->flags = p->tcfp_flags;
	422	opt->action = p->tcf_action;
036bb443 VB	423	opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
036bb443 VB	424	opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
1da177e4	425
71d0ed70	426	if (p->tcfp_keys_ex) {
85eb9af1 DC	427	if (tcf_pedit_key_ex_dump(skb,
	428	p->tcfp_keys_ex,
	429	p->tcfp_nkeys))
	430	goto nla_put_failure;
71d0ed70 AV	431
	432	if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
	433	goto nla_put_failure;
	434	} else {
	435	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
	436	goto nla_put_failure;
	437	}
48d8ee16 JHS	438
48d8ee16 JHS	439	tcf_tm_dump(&t, &p->tcf_tm);
9854518e	440	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
1b34ec43	441	goto nla_put_failure;
67b0c1a3	442	spin_unlock_bh(&p->tcf_lock);
48d8ee16	443
541673c8	444	kfree(opt);
1da177e4 LT	445	return skb->len;
1da177e4 LT	446
7ba699c6	447	nla_put_failure:
67b0c1a3	448	spin_unlock_bh(&p->tcf_lock);
dc5fc579	449	nlmsg_trim(skb, b);
541673c8	450	kfree(opt);
1da177e4 LT	451	return -1;
	452	}
	453
ddf97ccd WC	454	static int tcf_pedit_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	455	struct netlink_callback *cb, int type,
41780105 AA	456	const struct tc_action_ops *ops,
41780105 AA	457	struct netlink_ext_ack *extack)
ddf97ccd WC	458	{
	459	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	460
b3620145	461	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
ddf97ccd WC	462	}
ddf97ccd WC	463
f061b48c	464	static int tcf_pedit_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	465	{
	466	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	467
65a206c0	468	return tcf_idr_search(tn, a, index);
ddf97ccd WC	469	}
ddf97ccd WC	470
e9ce1cd3	471	static struct tc_action_ops act_pedit_ops = {
1da177e4 LT	472	.kind = "pedit",
1da177e4 LT	473	.type = TCA_ACT_PEDIT,
1da177e4	474	.owner = THIS_MODULE,
6a2b401c	475	.act = tcf_pedit_act,
1da177e4 LT	476	.dump = tcf_pedit_dump,
1da177e4 LT	477	.cleanup = tcf_pedit_cleanup,
1da177e4	478	.init = tcf_pedit_init,
ddf97ccd WC	479	.walk = tcf_pedit_walker,
ddf97ccd WC	480	.lookup = tcf_pedit_search,
a85a970a	481	.size = sizeof(struct tcf_pedit),
ddf97ccd WC	482	};
	483
	484	static __net_init int pedit_init_net(struct net *net)
	485	{
	486	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	487
c7e460ce	488	return tc_action_net_init(tn, &act_pedit_ops);
ddf97ccd WC	489	}
ddf97ccd WC	490
039af9c6	491	static void __net_exit pedit_exit_net(struct list_head *net_list)
ddf97ccd	492	{
039af9c6	493	tc_action_net_exit(net_list, pedit_net_id);
ddf97ccd WC	494	}
	495
	496	static struct pernet_operations pedit_net_ops = {
	497	.init = pedit_init_net,
039af9c6	498	.exit_batch = pedit_exit_net,
ddf97ccd WC	499	.id = &pedit_net_id,
ddf97ccd WC	500	.size = sizeof(struct tc_action_net),
1da177e4 LT	501	};
	502
	503	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	504	MODULE_DESCRIPTION("Generic Packet Editor actions");
	505	MODULE_LICENSE("GPL");
	506
e9ce1cd3	507	static int __init pedit_init_module(void)
1da177e4	508	{
ddf97ccd	509	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	510	}
1da177e4 LT	511
e9ce1cd3	512	static void __exit pedit_cleanup_module(void)
1da177e4	513	{
ddf97ccd	514	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	515	}
	516
	517	module_init(pedit_init_module);
	518	module_exit(pedit_cleanup_module);