[mirror_ubuntu-bionic-kernel.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)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	struct nlattr *tb[TCA_PEDIT_MAX + 1];
	struct nlattr *pattr;
	struct tc_pedit *parm;
	int ret = 0, err;
	struct tcf_pedit *p;
	struct tc_pedit_key *keys = NULL;
	struct tcf_pedit_key_ex *keys_ex;
	int ksize;

	if (nla == NULL)
		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)
		return -EINVAL;

	parm = nla_data(pattr);
	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
	if (nla_len(pattr) < sizeof(*parm) + ksize)
		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);

	if (!tcf_idr_check(tn, parm->index, a, bind)) {
		if (!parm->nkeys)
			return -EINVAL;
		ret = tcf_idr_create(tn, parm->index, est, a,
				     &act_pedit_ops, bind, false);
		if (ret)
			return ret;
		p = to_pedit(*a);
		keys = kmalloc(ksize, GFP_KERNEL);
		if (keys == NULL) {
			tcf_idr_release(*a, bind);
			kfree(keys_ex);
			return -ENOMEM;
		}
		ret = ACT_P_CREATED;
	} else {
		if (bind)
			return 0;
		tcf_idr_release(*a, bind);
		if (!ovr)
			return -EEXIST;
		p = to_pedit(*a);
		if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
			keys = kmalloc(ksize, GFP_KERNEL);
			if (!keys) {
				kfree(keys_ex);
				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);

	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;
}

static void tcf_pedit_cleanup(struct tc_action *a, int bind)
{
	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(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, _data;
			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 filter pedit bad header type specified (0x%x)\n",
					htype);
				goto bad;
			}

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

				if (!offset_valid(skb, hoffset + tkey->at)) {
					pr_info("tc filter pedit 'at' offset %d out of bounds\n",
						hoffset + tkey->at);
					goto bad;
				}
				d = skb_header_pointer(skb, hoffset + 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_valid(skb, hoffset + offset)) {
				pr_info("tc filter pedit offset %d out of bounds\n",
					hoffset + offset);
				goto bad;
			}

			ptr = skb_header_pointer(skb, hoffset + offset, 4, &_data);
			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 filter pedit bad command (%d)\n",
					cmd);
				goto bad;
			}

			*ptr = ((*ptr & tkey->mask) ^ val);
			if (ptr == &_data)
				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;

	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 (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;

	kfree(opt);
	return skb->len;

nla_put_failure:
	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 tc_action_net *tn = net_generic(net, pedit_net_id);

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

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,
	.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(net, tn, &act_pedit_ops);
}

static void __net_exit pedit_exit_net(struct net *net)
{
	struct tc_action_net *tn = net_generic(net, pedit_net_id);

	tc_action_net_exit(tn);
}

static struct pernet_operations pedit_net_ops = {
	.init = pedit_init_net,
	.exit = 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
49720797 DC	112	if (!keys_start)
49720797 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);
49720797 DC	118	if (!key_start)
49720797 DC	119	goto nla_failure;
71d0ed70	120
853a14ba	121	if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) \|\|
49720797 DC	122	nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
49720797 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;
49720797 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,
c1b52739	140	int ovr, int bind)
1da177e4	141	{
ddf97ccd	142	struct tc_action_net *tn = net_generic(net, pedit_net_id);
7ba699c6	143	struct nlattr *tb[TCA_PEDIT_MAX + 1];
71d0ed70	144	struct nlattr *pattr;
1da177e4	145	struct tc_pedit *parm;
cee63723	146	int ret = 0, err;
1da177e4 LT	147	struct tcf_pedit *p;
1da177e4 LT	148	struct tc_pedit_key *keys = NULL;
71d0ed70	149	struct tcf_pedit_key_ex *keys_ex;
1da177e4 LT	150	int ksize;
1da177e4 LT	151
cee63723	152	if (nla == NULL)
1da177e4 LT	153	return -EINVAL;
1da177e4 LT	154
fceb6435	155	err = nla_parse_nested(tb, TCA_PEDIT_MAX, nla, pedit_policy, NULL);
cee63723 PM	156	if (err < 0)
	157	return err;
	158
71d0ed70 AV	159	pattr = tb[TCA_PEDIT_PARMS];
	160	if (!pattr)
	161	pattr = tb[TCA_PEDIT_PARMS_EX];
	162	if (!pattr)
1da177e4	163	return -EINVAL;
71d0ed70 AV	164
71d0ed70 AV	165	parm = nla_data(pattr);
1da177e4	166	ksize = parm->nkeys * sizeof(struct tc_pedit_key);
71d0ed70	167	if (nla_len(pattr) < sizeof(*parm) + ksize)
1da177e4 LT	168	return -EINVAL;
1da177e4 LT	169
71d0ed70 AV	170	keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys);
	171	if (IS_ERR(keys_ex))
	172	return PTR_ERR(keys_ex);
	173
65a206c0	174	if (!tcf_idr_check(tn, parm->index, a, bind)) {
1da177e4 LT	175	if (!parm->nkeys)
1da177e4 LT	176	return -EINVAL;
65a206c0 CM	177	ret = tcf_idr_create(tn, parm->index, est, a,
65a206c0 CM	178	&act_pedit_ops, bind, false);
86062033 WC	179	if (ret)
86062033 WC	180	return ret;
a85a970a	181	p = to_pedit(*a);
1da177e4 LT	182	keys = kmalloc(ksize, GFP_KERNEL);
1da177e4 LT	183	if (keys == NULL) {
f37f01ed	184	tcf_idr_release(*a, bind);
71d0ed70	185	kfree(keys_ex);
1da177e4 LT	186	return -ENOMEM;
	187	}
	188	ret = ACT_P_CREATED;
	189	} else {
1a29321e JHS	190	if (bind)
1a29321e JHS	191	return 0;
65a206c0	192	tcf_idr_release(*a, bind);
1a29321e	193	if (!ovr)
1da177e4	194	return -EEXIST;
a85a970a	195	p = to_pedit(*a);
e9ce1cd3	196	if (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys) {
1da177e4	197	keys = kmalloc(ksize, GFP_KERNEL);
71d0ed70 AV	198	if (!keys) {
71d0ed70 AV	199	kfree(keys_ex);
1da177e4	200	return -ENOMEM;
71d0ed70	201	}
1da177e4 LT	202	}
	203	}
	204
e9ce1cd3 DM	205	spin_lock_bh(&p->tcf_lock);
	206	p->tcfp_flags = parm->flags;
	207	p->tcf_action = parm->action;
1da177e4	208	if (keys) {
e9ce1cd3 DM	209	kfree(p->tcfp_keys);
	210	p->tcfp_keys = keys;
	211	p->tcfp_nkeys = parm->nkeys;
1da177e4	212	}
e9ce1cd3	213	memcpy(p->tcfp_keys, parm->keys, ksize);
71d0ed70 AV	214
	215	kfree(p->tcfp_keys_ex);
	216	p->tcfp_keys_ex = keys_ex;
	217
e9ce1cd3	218	spin_unlock_bh(&p->tcf_lock);
1da177e4	219	if (ret == ACT_P_CREATED)
65a206c0	220	tcf_idr_insert(tn, *a);
1da177e4 LT	221	return ret;
	222	}
	223
a5b5c958	224	static void tcf_pedit_cleanup(struct tc_action *a, int bind)
1da177e4	225	{
a85a970a	226	struct tcf_pedit *p = to_pedit(a);
a5b5c958 WC	227	struct tc_pedit_key *keys = p->tcfp_keys;
a5b5c958 WC	228	kfree(keys);
71d0ed70	229	kfree(p->tcfp_keys_ex);
1da177e4 LT	230	}
1da177e4 LT	231
95c2027b AV	232	static bool offset_valid(struct sk_buff *skb, int offset)
	233	{
	234	if (offset > 0 && offset > skb->len)
	235	return false;
	236
	237	if (offset < 0 && -offset > skb_headroom(skb))
	238	return false;
	239
	240	return true;
	241	}
	242
71d0ed70 AV	243	static int pedit_skb_hdr_offset(struct sk_buff *skb,
	244	enum pedit_header_type htype, int *hoffset)
	245	{
	246	int ret = -EINVAL;
	247
	248	switch (htype) {
	249	case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
	250	if (skb_mac_header_was_set(skb)) {
	251	*hoffset = skb_mac_offset(skb);
	252	ret = 0;
	253	}
	254	break;
	255	case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
	256	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
	257	case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
	258	*hoffset = skb_network_offset(skb);
	259	ret = 0;
	260	break;
	261	case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
	262	case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
	263	if (skb_transport_header_was_set(skb)) {
	264	*hoffset = skb_transport_offset(skb);
	265	ret = 0;
	266	}
	267	break;
	268	default:
	269	ret = -EINVAL;
	270	break;
	271	};
	272
	273	return ret;
	274	}
	275
dc7f9f6e	276	static int tcf_pedit(struct sk_buff skb, const struct tc_action a,
e9ce1cd3	277	struct tcf_result *res)
1da177e4	278	{
a85a970a	279	struct tcf_pedit *p = to_pedit(a);
4749c3ef	280	int i;
1da177e4	281
14bbd6a5	282	if (skb_unclone(skb, GFP_ATOMIC))
cc7ec456	283	return p->tcf_action;
1da177e4	284
e9ce1cd3	285	spin_lock(&p->tcf_lock);
1da177e4	286
9c4a4e48	287	tcf_lastuse_update(&p->tcf_tm);
1da177e4	288
e9ce1cd3 DM	289	if (p->tcfp_nkeys > 0) {
e9ce1cd3 DM	290	struct tc_pedit_key *tkey = p->tcfp_keys;
71d0ed70 AV	291	struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex;
71d0ed70 AV	292	enum pedit_header_type htype = TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
853a14ba	293	enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
1da177e4	294
e9ce1cd3	295	for (i = p->tcfp_nkeys; i > 0; i--, tkey++) {
db2c2417	296	u32 *ptr, _data;
1da177e4	297	int offset = tkey->off;
71d0ed70	298	int hoffset;
853a14ba	299	u32 val;
71d0ed70 AV	300	int rc;
	301
	302	if (tkey_ex) {
	303	htype = tkey_ex->htype;
853a14ba AV	304	cmd = tkey_ex->cmd;
853a14ba AV	305
71d0ed70 AV	306	tkey_ex++;
	307	}
	308
	309	rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
	310	if (rc) {
	311	pr_info("tc filter pedit bad header type specified (0x%x)\n",
	312	htype);
	313	goto bad;
	314	}
1da177e4 LT	315
1da177e4 LT	316	if (tkey->offmask) {
db2c2417 CG	317	char *d, _d;
db2c2417 CG	318
71d0ed70	319	if (!offset_valid(skb, hoffset + tkey->at)) {
95c2027b	320	pr_info("tc filter pedit 'at' offset %d out of bounds\n",
71d0ed70	321	hoffset + tkey->at);
95c2027b AV	322	goto bad;
95c2027b AV	323	}
71d0ed70	324	d = skb_header_pointer(skb, hoffset + tkey->at, 1,
db2c2417 CG	325	&_d);
db2c2417 CG	326	if (!d)
1da177e4	327	goto bad;
db2c2417	328	offset += (*d & tkey->offmask) >> tkey->shift;
1da177e4 LT	329	}
	330
	331	if (offset % 4) {
6ff9c364	332	pr_info("tc filter pedit"
6ff9c364	333	" offset must be on 32 bit boundaries\n");
1da177e4 LT	334	goto bad;
1da177e4 LT	335	}
95c2027b	336
71d0ed70	337	if (!offset_valid(skb, hoffset + offset)) {
95c2027b	338	pr_info("tc filter pedit offset %d out of bounds\n",
71d0ed70	339	hoffset + offset);
1da177e4 LT	340	goto bad;
	341	}
	342
71d0ed70	343	ptr = skb_header_pointer(skb, hoffset + offset, 4, &_data);
db2c2417 CG	344	if (!ptr)
db2c2417 CG	345	goto bad;
1da177e4	346	/* just do it, baby */
853a14ba AV	347	switch (cmd) {
	348	case TCA_PEDIT_KEY_EX_CMD_SET:
	349	val = tkey->val;
	350	break;
	351	case TCA_PEDIT_KEY_EX_CMD_ADD:
	352	val = (*ptr + tkey->val) & ~tkey->mask;
	353	break;
	354	default:
	355	pr_info("tc filter pedit bad command (%d)\n",
	356	cmd);
	357	goto bad;
	358	}
	359
	360	ptr = ((ptr & tkey->mask) ^ val);
db2c2417	361	if (ptr == &_data)
71d0ed70	362	skb_store_bits(skb, hoffset + offset, ptr, 4);
1da177e4	363	}
10297b99	364
1da177e4	365	goto done;
6ff9c364	366	} else
6ff9c364	367	WARN(1, "pedit BUG: index %d\n", p->tcf_index);
1da177e4 LT	368
1da177e4 LT	369	bad:
e9ce1cd3	370	p->tcf_qstats.overlimits++;
1da177e4	371	done:
bfe0d029	372	bstats_update(&p->tcf_bstats, skb);
e9ce1cd3 DM	373	spin_unlock(&p->tcf_lock);
e9ce1cd3 DM	374	return p->tcf_action;
1da177e4 LT	375	}
1da177e4 LT	376
e9ce1cd3 DM	377	static int tcf_pedit_dump(struct sk_buff skb, struct tc_action a,
e9ce1cd3 DM	378	int bind, int ref)
1da177e4	379	{
27a884dc	380	unsigned char *b = skb_tail_pointer(skb);
a85a970a	381	struct tcf_pedit *p = to_pedit(a);
1da177e4	382	struct tc_pedit *opt;
1da177e4	383	struct tcf_t t;
10297b99 YH	384	int s;
10297b99 YH	385
e9ce1cd3	386	s = sizeof(opt) + p->tcfp_nkeys sizeof(struct tc_pedit_key);
1da177e4 LT	387
1da177e4 LT	388	/* netlink spinlocks held above us - must use ATOMIC */
0da974f4	389	opt = kzalloc(s, GFP_ATOMIC);
e9ce1cd3	390	if (unlikely(!opt))
1da177e4	391	return -ENOBUFS;
1da177e4	392
e9ce1cd3 DM	393	memcpy(opt->keys, p->tcfp_keys,
	394	p->tcfp_nkeys * sizeof(struct tc_pedit_key));
	395	opt->index = p->tcf_index;
	396	opt->nkeys = p->tcfp_nkeys;
	397	opt->flags = p->tcfp_flags;
	398	opt->action = p->tcf_action;
	399	opt->refcnt = p->tcf_refcnt - ref;
	400	opt->bindcnt = p->tcf_bindcnt - bind;
1da177e4	401
71d0ed70	402	if (p->tcfp_keys_ex) {
49720797 DC	403	if (tcf_pedit_key_ex_dump(skb,
	404	p->tcfp_keys_ex,
	405	p->tcfp_nkeys))
	406	goto nla_put_failure;
71d0ed70 AV	407
	408	if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
	409	goto nla_put_failure;
	410	} else {
	411	if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
	412	goto nla_put_failure;
	413	}
48d8ee16 JHS	414
48d8ee16 JHS	415	tcf_tm_dump(&t, &p->tcf_tm);
9854518e	416	if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
1b34ec43	417	goto nla_put_failure;
48d8ee16	418
541673c8	419	kfree(opt);
1da177e4 LT	420	return skb->len;
1da177e4 LT	421
7ba699c6	422	nla_put_failure:
dc5fc579	423	nlmsg_trim(skb, b);
541673c8	424	kfree(opt);
1da177e4 LT	425	return -1;
	426	}
	427
ddf97ccd WC	428	static int tcf_pedit_walker(struct net net, struct sk_buff skb,
ddf97ccd WC	429	struct netlink_callback *cb, int type,
a85a970a	430	const struct tc_action_ops *ops)
ddf97ccd WC	431	{
	432	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	433
a85a970a	434	return tcf_generic_walker(tn, skb, cb, type, ops);
ddf97ccd WC	435	}
ddf97ccd WC	436
a85a970a	437	static int tcf_pedit_search(struct net net, struct tc_action *a, u32 index)
ddf97ccd WC	438	{
	439	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	440
65a206c0	441	return tcf_idr_search(tn, a, index);
ddf97ccd WC	442	}
ddf97ccd WC	443
e9ce1cd3	444	static struct tc_action_ops act_pedit_ops = {
1da177e4 LT	445	.kind = "pedit",
1da177e4 LT	446	.type = TCA_ACT_PEDIT,
1da177e4 LT	447	.owner = THIS_MODULE,
	448	.act = tcf_pedit,
	449	.dump = tcf_pedit_dump,
	450	.cleanup = tcf_pedit_cleanup,
1da177e4	451	.init = tcf_pedit_init,
ddf97ccd WC	452	.walk = tcf_pedit_walker,
ddf97ccd WC	453	.lookup = tcf_pedit_search,
a85a970a	454	.size = sizeof(struct tcf_pedit),
ddf97ccd WC	455	};
	456
	457	static __net_init int pedit_init_net(struct net *net)
	458	{
	459	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	460
8f4d0354	461	return tc_action_net_init(net, tn, &act_pedit_ops);
ddf97ccd WC	462	}
	463
	464	static void __net_exit pedit_exit_net(struct net *net)
	465	{
	466	struct tc_action_net *tn = net_generic(net, pedit_net_id);
	467
	468	tc_action_net_exit(tn);
	469	}
	470
	471	static struct pernet_operations pedit_net_ops = {
	472	.init = pedit_init_net,
	473	.exit = pedit_exit_net,
	474	.id = &pedit_net_id,
	475	.size = sizeof(struct tc_action_net),
1da177e4 LT	476	};
	477
	478	MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
	479	MODULE_DESCRIPTION("Generic Packet Editor actions");
	480	MODULE_LICENSE("GPL");
	481
e9ce1cd3	482	static int __init pedit_init_module(void)
1da177e4	483	{
ddf97ccd	484	return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	485	}
1da177e4 LT	486
e9ce1cd3	487	static void __exit pedit_cleanup_module(void)
1da177e4	488	{
ddf97ccd	489	tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
1da177e4 LT	490	}
	491
	492	module_init(pedit_init_module);
	493	module_exit(pedit_cleanup_module);
	494