[linux-2.6-block.git] / net / sched / act_pedit.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/sched/act_pedit.c	Generic packet editor
 *
 * 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>
#include <net/pkt_cls.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_deprecated(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_noflag(skb,
							  TCA_PEDIT_KEYS_EX);

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

		key_start = nla_nest_start_noflag(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 tcf_proto *tp, struct netlink_ext_ack *extack)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	struct nlattr *tb[TCA_PEDIT_MAX + 1];
	struct tcf_chain *goto_ch = NULL;
	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_deprecated(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;
	}

	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
	if (err < 0) {
		ret = err;
		goto out_release;
	}
	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 put_chain;
		}
		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;
	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);

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

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

put_chain:
	if (goto_ch)
		tcf_chain_put_by_act(goto_ch);
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 = struct_size(opt, keys, p->tcfp_nkeys);

	/* 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",
	.id		=	TCA_ID_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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4	2	/*
0c6965dd	3	* net/sched/act_pedit.c Generic packet editor
1da177e4	4	*
1da177e4 LT	5	* Authors: Jamal Hadi Salim (2002-4)
	6	*/
	7
1da177e4 LT	8	#include <linux/types.h>
1da177e4 LT	9	#include <linux/kernel.h>
1da177e4	10	#include <linux/string.h>
1da177e4	11	#include <linux/errno.h>
1da177e4 LT	12	#include <linux/skbuff.h>
	13	#include <linux/rtnetlink.h>
	14	#include <linux/module.h>
	15	#include <linux/init.h>
5a0e3ad6	16	#include <linux/slab.h>
dc5fc579	17	#include <net/netlink.h>
1da177e4 LT	18	#include <net/pkt_sched.h>
	19	#include <linux/tc_act/tc_pedit.h>
	20	#include <net/tc_act/tc_pedit.h>
71d0ed70	21	#include <uapi/linux/tc_act/tc_pedit.h>
6ac86ca3	22	#include <net/pkt_cls.h>
1da177e4	23
c7d03a00	24	static unsigned int pedit_net_id;
a85a970a	25	static struct tc_action_ops act_pedit_ops;
ddf97ccd	26
53b2bf3f	27	static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
53f7e35f	28	[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
71d0ed70	29	[TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
53b2bf3f PM	30	};
53b2bf3f PM	31
71d0ed70 AV	32	static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
71d0ed70 AV	33	[TCA_PEDIT_KEY_EX_HTYPE] = { .type = NLA_U16 },
853a14ba	34	[TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 },
71d0ed70 AV	35	};
	36
	37	static struct tcf_pedit_key_ex tcf_pedit_keys_ex_parse(struct nlattr nla,
	38	u8 n)
	39	{
	40	struct tcf_pedit_key_ex *keys_ex;
	41	struct tcf_pedit_key_ex *k;
	42	const struct nlattr *ka;
	43	int err = -EINVAL;
	44	int rem;
	45
	46	if (!nla \|\| !n)
	47	return NULL;
	48
	49	keys_ex = kcalloc(n, sizeof(*k), GFP_KERNEL);
	50	if (!keys_ex)
	51	return ERR_PTR(-ENOMEM);
	52
	53	k = keys_ex;
	54
	55	nla_for_each_nested(ka, nla, rem) {
	56	struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
	57
	58	if (!n) {
	59	err = -EINVAL;
	60	goto err_out;
	61	}
	62	n--;
	63
	64	if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
	65	err = -EINVAL;
	66	goto err_out;
	67	}
	68
8cb08174 JB	69	err = nla_parse_nested_deprecated(tb, TCA_PEDIT_KEY_EX_MAX,
	70	ka, pedit_key_ex_policy,
	71	NULL);
71d0ed70 AV	72	if (err)
	73	goto err_out;
	74
853a14ba AV	75	if (!tb[TCA_PEDIT_KEY_EX_HTYPE] \|\|
853a14ba AV	76	!tb[TCA_PEDIT_KEY_EX_CMD]) {
71d0ed70 AV	77	err = -EINVAL;
	78	goto err_out;
	79	}
	80
	81	k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
853a14ba	82	k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
71d0ed70	83
853a14ba AV	84	if (k->htype > TCA_PEDIT_HDR_TYPE_MAX \|\|
853a14ba AV	85	k->cmd > TCA_PEDIT_CMD_MAX) {
71d0ed70 AV	86	err = -EINVAL;
	87	goto err_out;
	88	}
	89
	90	k++;
	91	}
	92
c4f65b09 DC	93	if (n) {
c4f65b09 DC	94	err = -EINVAL;
71d0ed70	95	goto err_out;
c4f65b09	96	}
71d0ed70 AV	97
	98	return keys_ex;
	99
	100	err_out:
	101	kfree(keys_ex);
	102	return ERR_PTR(err);
	103	}
	104
	105	static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
	106	struct tcf_pedit_key_ex *keys_ex, int n)
	107	{
ae0be8de MK	108	struct nlattr *keys_start = nla_nest_start_noflag(skb,
ae0be8de MK	109	TCA_PEDIT_KEYS_EX);
71d0ed70	110
85eb9af1 DC	111	if (!keys_start)
85eb9af1 DC	112	goto nla_failure;
71d0ed70 AV	113	for (; n > 0; n--) {
	114	struct nlattr *key_start;
	115
ae0be8de	116	key_start = nla_nest_start_noflag(skb, TCA_PEDIT_KEY_EX);
85eb9af1 DC	117	if (!key_start)
85eb9af1 DC	118	goto nla_failure;
71d0ed70	119
853a14ba	120	if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) \|\|
85eb9af1 DC	121	nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
85eb9af1 DC	122	goto nla_failure;
71d0ed70 AV	123
	124	nla_nest_end(skb, key_start);
	125
	126	keys_ex++;
	127	}
	128
	129	nla_nest_end(skb, keys_start);
	130
	131	return 0;
85eb9af1 DC	132	nla_failure:
	133	nla_nest_cancel(skb, keys_start);
	134	return -EINVAL;
71d0ed70 AV	135	}
71d0ed70 AV	136
c1b52739	137	static int tcf_pedit_init(struct net net, struct nlattr nla,
a85a970a	138	struct nlattr est, struct tc_action *a,
789871bb	139	int ovr, int bind, bool rtnl_held,
85d0966f	140	struct tcf_proto tp, struct netlink_ext_ack extack)
1da177e4	141	{
ddf97ccd	142	struct tc_action_net *tn = net_generic(net, pedit_net_id);
7ba699c6	143	struct nlattr *tb[TCA_PEDIT_MAX + 1];
6ac86ca3	144	struct tcf_chain *goto_ch = NULL;
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
8cb08174 JB	158	err = nla_parse_nested_deprecated(tb, TCA_PEDIT_MAX, nla,
8cb08174 JB	159	pedit_policy, NULL);
cee63723 PM	160	if (err < 0)
	161	return err;
	162
71d0ed70 AV	163	pattr = tb[TCA_PEDIT_PARMS];
	164	if (!pattr)
	165	pattr = tb[TCA_PEDIT_PARMS_EX];
9868c0b2 RM	166	if (!pattr) {
9868c0b2 RM	167	NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
1da177e4	168	return -EINVAL;
9868c0b2	169	}
71d0ed70 AV	170
71d0ed70 AV	171	parm = nla_data(pattr);
1da177e4	172	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
9868c0b2 RM	173	if (nla_len(pattr) < sizeof(*parm) + ksize) {
9868c0b2 RM	174	NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
1da177e4	175	return -EINVAL;
9868c0b2	176	}
1da177e4	177
71d0ed70 AV	178	keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
	179	if (IS_ERR(keys_ex))
	180	return PTR_ERR(keys_ex);
	181
0190c1d4 VB	182	err = tcf_idr_check_alloc(tn, &parm->index, a, bind);
0190c1d4 VB	183	if (!err) {
9868c0b2	184	if (!parm->nkeys) {
0190c1d4	185	tcf_idr_cleanup(tn, parm->index);
9868c0b2	186	NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
30e99ed6 WY	187	ret = -EINVAL;
30e99ed6 WY	188	goto out_free;
9868c0b2	189	}
65a206c0 CM	190	ret = tcf_idr_create(tn, parm->index, est, a,
65a206c0 CM	191	&act_pedit_ops, bind, false);
0190c1d4 VB	192	if (ret) {
0190c1d4 VB	193	tcf_idr_cleanup(tn, parm->index);
30e99ed6	194	goto out_free;
0190c1d4	195	}
1da177e4	196	ret = ACT_P_CREATED;
0190c1d4	197	} else if (err > 0) {
1a29321e	198	if (bind)
30e99ed6	199	goto out_free;
30e99ed6 WY	200	if (!ovr) {
30e99ed6 WY	201	ret = -EEXIST;
67b0c1a3	202	goto out_release;
1da177e4	203	}
0190c1d4	204	} else {
19ab6910 DC	205	ret = err;
19ab6910 DC	206	goto out_free;
1da177e4 LT	207	}
1da177e4 LT	208
6ac86ca3 DC	209	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
	210	if (err < 0) {
	211	ret = err;
	212	goto out_release;
	213	}
67b0c1a3	214	p = to_pedit(*a);
e9ce1cd3	215	spin_lock_bh(&p->tcf_lock);
67b0c1a3 VB	216
	217	if (ret == ACT_P_CREATED \|\|
	218	(p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) {
	219	keys = kmalloc(ksize, GFP_ATOMIC);
	220	if (!keys) {
	221	spin_unlock_bh(&p->tcf_lock);
	222	ret = -ENOMEM;
6ac86ca3	223	goto put_chain;
67b0c1a3	224	}
e9ce1cd3 DM	225	kfree(p->tcfp_keys);
	226	p->tcfp_keys = keys;
	227	p->tcfp_nkeys = parm->nkeys;
1da177e4	228	}
e9ce1cd3	229	memcpy(p->tcfp_keys, parm->keys, ksize);
71d0ed70	230
67b0c1a3	231	p->tcfp_flags = parm->flags;
6ac86ca3	232	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
67b0c1a3	233
71d0ed70 AV	234	kfree(p->tcfp_keys_ex);
	235	p->tcfp_keys_ex = keys_ex;
	236
e9ce1cd3	237	spin_unlock_bh(&p->tcf_lock);
6ac86ca3 DC	238	if (goto_ch)
6ac86ca3 DC	239	tcf_chain_put_by_act(goto_ch);
1da177e4	240	if (ret == ACT_P_CREATED)
65a206c0	241	tcf_idr_insert(tn, *a);
1da177e4	242	return ret;
67b0c1a3	243
6ac86ca3 DC	244	put_chain:
	245	if (goto_ch)
	246	tcf_chain_put_by_act(goto_ch);
67b0c1a3 VB	247	out_release:
67b0c1a3 VB	248	tcf_idr_release(*a, bind);
30e99ed6 WY	249	out_free:
	250	kfree(keys_ex);
	251	return ret;
	252
1da177e4 LT	253	}
1da177e4 LT	254
9a63b255	255	static void tcf_pedit_cleanup(struct tc_action *a)
1da177e4	256	{
a85a970a	257	struct tcf_pedit *p = to_pedit(a);
a5b5c958	258	struct tc_pedit_key *keys = p->tcfp_keys;
80f0f574	259
a5b5c958	260	kfree(keys);
71d0ed70	261	kfree(p->tcfp_keys_ex);
1da177e4 LT	262	}
1da177e4 LT	263
95c2027b AV	264	static bool offset_valid(struct sk_buff *skb, int offset)
	265	{
	266	if (offset > 0 && offset > skb->len)
	267	return false;
	268
	269	if (offset < 0 && -offset > skb_headroom(skb))
	270	return false;
	271
	272	return true;
	273	}
	274
71d0ed70 AV	275	static int pedit_skb_hdr_offset(struct sk_buff *skb,
	276	enum pedit_header_type htype, int *hoffset)
	277	{
	278	int ret = -EINVAL;
	279
	280	switch (htype) {
	281	case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
	282	if (skb_mac_header_was_set(skb)) {
	283	*hoffset = skb_mac_offset(skb);
	284	ret = 0;
	285	}
	286	break;
	287	case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
	288	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
	289	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
	290	*hoffset = skb_network_offset(skb);
	291	ret = 0;
	292	break;
	293	case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
	294	case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
	295	if (skb_transport_header_was_set(skb)) {
	296	*hoffset = skb_transport_offset(skb);
	297	ret = 0;
	298	}
	299	break;
	300	default:
	301	ret = -EINVAL;
	302	break;
0a80848e	303	}
71d0ed70 AV	304
	305	return ret;
	306	}
	307
6a2b401c JHS	308	static int tcf_pedit_act(struct sk_buff skb, const struct tc_action a,
6a2b401c JHS	309	struct tcf_result *res)
1da177e4	310	{
a85a970a	311	struct tcf_pedit *p = to_pedit(a);
4749c3ef	312	int i;
1da177e4	313
14bbd6a5	314	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	315	return p->tcf_action;
1da177e4	316
e9ce1cd3	317	spin_lock(&p->tcf_lock);
1da177e4	318
9c4a4e48	319	tcf_lastuse_update(&p->tcf_tm);
1da177e4	320
e9ce1cd3 DM	321	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	322	struct tc_pedit_key *tkey = p->tcfp_keys;
71d0ed70	323	struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
80f0f574 RM	324	enum pedit_header_type htype =
80f0f574 RM	325	TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
853a14ba	326	enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
1da177e4	327
e9ce1cd3	328	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
544377cd	329	u32 *ptr, hdata;
1da177e4	330	int offset = tkey->off;
71d0ed70	331	int hoffset;
853a14ba	332	u32 val;
71d0ed70 AV	333	int rc;
	334
	335	if (tkey_ex) {
	336	htype = tkey_ex->htype;
853a14ba AV	337	cmd = tkey_ex->cmd;
853a14ba AV	338
71d0ed70 AV	339	tkey_ex++;
	340	}
	341
	342	rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
	343	if (rc) {
95b0d2dc	344	pr_info("tc action pedit bad header type specified (0x%x)\n",
71d0ed70 AV	345	htype);
	346	goto bad;
	347	}
1da177e4 LT	348
1da177e4 LT	349	if (tkey->offmask) {
43052741	350	u8 *d, _d;
db2c2417	351
71d0ed70	352	if (!offset_valid(skb, hoffset + tkey->at)) {
95b0d2dc	353	pr_info("tc action pedit 'at' offset %d out of bounds\n",
71d0ed70	354	hoffset + tkey->at);
95c2027b AV	355	goto bad;
95c2027b AV	356	}
80f0f574	357	d = skb_header_pointer(skb, hoffset + tkey->at,
6ff7586e	358	sizeof(_d), &_d);
db2c2417	359	if (!d)
1da177e4	360	goto bad;
db2c2417	361	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	362	}
	363
	364	if (offset % 4) {
95b0d2dc	365	pr_info("tc action pedit offset must be on 32 bit boundaries\n");
1da177e4 LT	366	goto bad;
1da177e4 LT	367	}
95c2027b	368
71d0ed70	369	if (!offset_valid(skb, hoffset + offset)) {
95b0d2dc	370	pr_info("tc action pedit offset %d out of bounds\n",
71d0ed70	371	hoffset + offset);
1da177e4 LT	372	goto bad;
	373	}
	374
80f0f574	375	ptr = skb_header_pointer(skb, hoffset + offset,
6ff7586e	376	sizeof(hdata), &hdata);
db2c2417 CG	377	if (!ptr)
db2c2417 CG	378	goto bad;
1da177e4	379	/* just do it, baby */
853a14ba AV	380	switch (cmd) {
	381	case TCA_PEDIT_KEY_EX_CMD_SET:
	382	val = tkey->val;
	383	break;
	384	case TCA_PEDIT_KEY_EX_CMD_ADD:
	385	val = (*ptr + tkey->val) & ~tkey->mask;
	386	break;
	387	default:
95b0d2dc	388	pr_info("tc action pedit bad command (%d)\n",
853a14ba AV	389	cmd);
	390	goto bad;
	391	}
	392
	393	ptr = ((ptr & tkey->mask) ^ val);
544377cd	394	if (ptr == &hdata)
71d0ed70	395	skb_store_bits(skb, hoffset + offset, ptr, 4);
1da177e4	396	}
10297b99	397
1da177e4	398	goto done;
80f0f574	399	} else {
6ff9c364	400	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
80f0f574	401	}
1da177e4 LT	402
1da177e4 LT	403	bad:
e9ce1cd3	404	p->tcf_qstats.overlimits++;
1da177e4	405	done:
bfe0d029	406	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	407	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	408	return p->tcf_action;
1da177e4 LT	409	}
1da177e4 LT	410
e9ce1cd3 DM	411	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	412	int bind, int ref)
1da177e4	413	{
27a884dc	414	unsigned char *b = skb_tail_pointer(skb);
a85a970a	415	struct tcf_pedit *p = to_pedit(a);
1da177e4	416	struct tc_pedit *opt;
1da177e4	417	struct tcf_t t;
10297b99 YH	418	int s;
10297b99 YH	419
8fe5756c	420	s = struct_size(opt, keys, p->tcfp_nkeys);
1da177e4 LT	421
1da177e4 LT	422	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	423	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	424	if (unlikely(!opt))
1da177e4	425	return -ENOBUFS;
1da177e4	426
67b0c1a3	427	spin_lock_bh(&p->tcf_lock);
e9ce1cd3 DM	428	memcpy(opt->keys, p->tcfp_keys,
	429	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	430	opt->index = p->tcf_index;
	431	opt->nkeys = p->tcfp_nkeys;
	432	opt->flags = p->tcfp_flags;
	433	opt->action = p->tcf_action;
036bb443 VB	434	opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
036bb443 VB	435	opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
1da177e4	436
71d0ed70	437	if (p->tcfp_keys_ex) {
85eb9af1 DC	438	if (tcf_pedit_key_ex_dump(skb,
	439	p->tcfp_keys_ex,
	440	p->tcfp_nkeys))
	441	goto nla_put_failure;
71d0ed70 AV	442
	443	if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
	444	goto nla_put_failure;
	445	} else {
	446	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
	447	goto nla_put_failure;
	448	}
48d8ee16 JHS	449
48d8ee16 JHS	450	tcf_tm_dump(&t, &p->tcf_tm);
9854518e	451	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
1b34ec43	452	goto nla_put_failure;
67b0c1a3	453	spin_unlock_bh(&p->tcf_lock);
48d8ee16	454
541673c8	455	kfree(opt);
1da177e4 LT	456	return skb->len;
1da177e4 LT	457
7ba699c6	458	nla_put_failure:
67b0c1a3	459	spin_unlock_bh(&p->tcf_lock);
dc5fc579	460	nlmsg_trim(skb, b);
541673c8	461	kfree(opt);
1da177e4 LT	462	return -1;
	463	}
	464
ddf97ccd WC	465	static int tcf_pedit_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	466	struct netlink_callback *cb, int type,
41780105 AA	467	const struct tc_action_ops *ops,
41780105 AA	468	struct netlink_ext_ack *extack)
ddf97ccd WC	469	{
	470	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	471
b3620145	472	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
ddf97ccd WC	473	}
ddf97ccd WC	474
f061b48c	475	static int tcf_pedit_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	476	{
	477	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	478
65a206c0	479	return tcf_idr_search(tn, a, index);
ddf97ccd WC	480	}
ddf97ccd WC	481
e9ce1cd3	482	static struct tc_action_ops act_pedit_ops = {
1da177e4	483	.kind = "pedit",
eddd2cf1	484	.id = TCA_ID_PEDIT,
1da177e4	485	.owner = THIS_MODULE,
6a2b401c	486	.act = tcf_pedit_act,
1da177e4 LT	487	.dump = tcf_pedit_dump,
1da177e4 LT	488	.cleanup = tcf_pedit_cleanup,
1da177e4	489	.init = tcf_pedit_init,
ddf97ccd WC	490	.walk = tcf_pedit_walker,
ddf97ccd WC	491	.lookup = tcf_pedit_search,
a85a970a	492	.size = sizeof(struct tcf_pedit),
ddf97ccd WC	493	};
	494
	495	static __net_init int pedit_init_net(struct net *net)
	496	{
	497	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	498
c7e460ce	499	return tc_action_net_init(tn, &act_pedit_ops);
ddf97ccd WC	500	}
ddf97ccd WC	501
039af9c6	502	static void __net_exit pedit_exit_net(struct list_head *net_list)
ddf97ccd	503	{
039af9c6	504	tc_action_net_exit(net_list, pedit_net_id);
ddf97ccd WC	505	}
	506
	507	static struct pernet_operations pedit_net_ops = {
	508	.init = pedit_init_net,
039af9c6	509	.exit_batch = pedit_exit_net,
ddf97ccd WC	510	.id = &pedit_net_id,
ddf97ccd WC	511	.size = sizeof(struct tc_action_net),
1da177e4 LT	512	};
	513
	514	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	515	MODULE_DESCRIPTION("Generic Packet Editor actions");
	516	MODULE_LICENSE("GPL");
	517
e9ce1cd3	518	static int __init pedit_init_module(void)
1da177e4	519	{
ddf97ccd	520	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	521	}
1da177e4 LT	522
e9ce1cd3	523	static void __exit pedit_cleanup_module(void)
1da177e4	524	{
ddf97ccd	525	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	526	}
	527
	528	module_init(pedit_init_module);
	529	module_exit(pedit_cleanup_module);