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v4.10.11
 
  1/*
  2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
  3 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 *
  9 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 10 */
 11
 12#include <linux/kernel.h>
 13#include <linux/if_vlan.h>
 14#include <linux/init.h>
 15#include <linux/module.h>
 16#include <linux/netlink.h>
 17#include <linux/netfilter.h>
 18#include <linux/netfilter/nf_tables.h>
 19#include <net/netfilter/nf_tables_core.h>
 20#include <net/netfilter/nf_tables.h>
 
 21/* For layer 4 checksum field offset. */
 22#include <linux/tcp.h>
 23#include <linux/udp.h>
 
 24#include <linux/icmpv6.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 25
 26/* add vlan header into the user buffer for if tag was removed by offloads */
 27static bool
 28nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
 29{
 30	int mac_off = skb_mac_header(skb) - skb->data;
 31	u8 vlan_len, *vlanh, *dst_u8 = (u8 *) d;
 32	struct vlan_ethhdr veth;
 33
 34	vlanh = (u8 *) &veth;
 35	if (offset < ETH_HLEN) {
 36		u8 ethlen = min_t(u8, len, ETH_HLEN - offset);
 37
 38		if (skb_copy_bits(skb, mac_off, &veth, ETH_HLEN))
 39			return false;
 40
 41		veth.h_vlan_proto = skb->vlan_proto;
 
 42
 43		memcpy(dst_u8, vlanh + offset, ethlen);
 44
 45		len -= ethlen;
 46		if (len == 0)
 47			return true;
 48
 49		dst_u8 += ethlen;
 50		offset = ETH_HLEN;
 51	} else if (offset >= VLAN_ETH_HLEN) {
 52		offset -= VLAN_HLEN;
 53		goto skip;
 54	}
 55
 56	veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb));
 57	veth.h_vlan_encapsulated_proto = skb->protocol;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 58
 59	vlanh += offset;
 
 
 
 
 
 
 
 
 
 
 60
 61	vlan_len = min_t(u8, len, VLAN_ETH_HLEN - offset);
 62	memcpy(dst_u8, vlanh, vlan_len);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 63
 64	len -= vlan_len;
 65	if (!len)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 66		return true;
 67
 68	dst_u8 += vlan_len;
 69 skip:
 70	return skb_copy_bits(skb, offset + mac_off, dst_u8, len) == 0;
 71}
 72
 73static void nft_payload_eval(const struct nft_expr *expr,
 74			     struct nft_regs *regs,
 75			     const struct nft_pktinfo *pkt)
 76{
 77	const struct nft_payload *priv = nft_expr_priv(expr);
 78	const struct sk_buff *skb = pkt->skb;
 79	u32 *dest = &regs->data[priv->dreg];
 80	int offset;
 81
 82	dest[priv->len / NFT_REG32_SIZE] = 0;
 
 
 83	switch (priv->base) {
 84	case NFT_PAYLOAD_LL_HEADER:
 85		if (!skb_mac_header_was_set(skb))
 86			goto err;
 87
 88		if (skb_vlan_tag_present(skb)) {
 
 89			if (!nft_payload_copy_vlan(dest, skb,
 90						   priv->offset, priv->len))
 91				goto err;
 92			return;
 93		}
 94		offset = skb_mac_header(skb) - skb->data;
 95		break;
 96	case NFT_PAYLOAD_NETWORK_HEADER:
 97		offset = skb_network_offset(skb);
 98		break;
 99	case NFT_PAYLOAD_TRANSPORT_HEADER:
100		if (!pkt->tprot_set)
 
 
 
 
 
 
101			goto err;
102		offset = pkt->xt.thoff;
103		break;
104	default:
105		BUG();
 
106	}
107	offset += priv->offset;
108
109	if (skb_copy_bits(skb, offset, dest, priv->len) < 0)
110		goto err;
111	return;
112err:
113	regs->verdict.code = NFT_BREAK;
114}
115
116static const struct nla_policy nft_payload_policy[NFTA_PAYLOAD_MAX + 1] = {
117	[NFTA_PAYLOAD_SREG]		= { .type = NLA_U32 },
118	[NFTA_PAYLOAD_DREG]		= { .type = NLA_U32 },
119	[NFTA_PAYLOAD_BASE]		= { .type = NLA_U32 },
120	[NFTA_PAYLOAD_OFFSET]		= { .type = NLA_U32 },
121	[NFTA_PAYLOAD_LEN]		= { .type = NLA_U32 },
122	[NFTA_PAYLOAD_CSUM_TYPE]	= { .type = NLA_U32 },
123	[NFTA_PAYLOAD_CSUM_OFFSET]	= { .type = NLA_U32 },
 
124};
125
126static int nft_payload_init(const struct nft_ctx *ctx,
127			    const struct nft_expr *expr,
128			    const struct nlattr * const tb[])
129{
130	struct nft_payload *priv = nft_expr_priv(expr);
131
132	priv->base   = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
133	priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
134	priv->len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
135	priv->dreg   = nft_parse_register(tb[NFTA_PAYLOAD_DREG]);
136
137	return nft_validate_register_store(ctx, priv->dreg, NULL,
138					   NFT_DATA_VALUE, priv->len);
 
139}
140
141static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
 
142{
143	const struct nft_payload *priv = nft_expr_priv(expr);
144
145	if (nft_dump_register(skb, NFTA_PAYLOAD_DREG, priv->dreg) ||
146	    nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
147	    nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
148	    nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)))
149		goto nla_put_failure;
150	return 0;
151
152nla_put_failure:
153	return -1;
154}
155
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
156static const struct nft_expr_ops nft_payload_ops = {
157	.type		= &nft_payload_type,
158	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload)),
159	.eval		= nft_payload_eval,
160	.init		= nft_payload_init,
161	.dump		= nft_payload_dump,
 
 
162};
163
164const struct nft_expr_ops nft_payload_fast_ops = {
165	.type		= &nft_payload_type,
166	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload)),
167	.eval		= nft_payload_eval,
168	.init		= nft_payload_init,
169	.dump		= nft_payload_dump,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
170};
171
172static inline void nft_csum_replace(__sum16 *sum, __wsum fsum, __wsum tsum)
173{
174	*sum = csum_fold(csum_add(csum_sub(~csum_unfold(*sum), fsum), tsum));
175	if (*sum == 0)
176		*sum = CSUM_MANGLED_0;
177}
178
179static bool nft_payload_udp_checksum(struct sk_buff *skb, unsigned int thoff)
180{
181	struct udphdr *uh, _uh;
182
183	uh = skb_header_pointer(skb, thoff, sizeof(_uh), &_uh);
184	if (!uh)
185		return false;
186
187	return uh->check;
188}
189
190static int nft_payload_l4csum_offset(const struct nft_pktinfo *pkt,
191				     struct sk_buff *skb,
192				     unsigned int *l4csum_offset)
193{
 
 
 
194	switch (pkt->tprot) {
195	case IPPROTO_TCP:
196		*l4csum_offset = offsetof(struct tcphdr, check);
197		break;
198	case IPPROTO_UDP:
199		if (!nft_payload_udp_checksum(skb, pkt->xt.thoff))
200			return -1;
201		/* Fall through. */
202	case IPPROTO_UDPLITE:
203		*l4csum_offset = offsetof(struct udphdr, check);
204		break;
205	case IPPROTO_ICMPV6:
206		*l4csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
207		break;
208	default:
209		return -1;
210	}
211
212	*l4csum_offset += pkt->xt.thoff;
 
 
 
 
 
 
 
 
 
 
 
 
 
213	return 0;
214}
215
216static int nft_payload_l4csum_update(const struct nft_pktinfo *pkt,
217				     struct sk_buff *skb,
218				     __wsum fsum, __wsum tsum)
219{
220	int l4csum_offset;
221	__sum16 sum;
222
223	/* If we cannot determine layer 4 checksum offset or this packet doesn't
224	 * require layer 4 checksum recalculation, skip this packet.
225	 */
226	if (nft_payload_l4csum_offset(pkt, skb, &l4csum_offset) < 0)
227		return 0;
228
229	if (skb_copy_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
230		return -1;
231
232	/* Checksum mangling for an arbitrary amount of bytes, based on
233	 * inet_proto_csum_replace*() functions.
234	 */
235	if (skb->ip_summed != CHECKSUM_PARTIAL) {
236		nft_csum_replace(&sum, fsum, tsum);
237		if (skb->ip_summed == CHECKSUM_COMPLETE) {
238			skb->csum = ~csum_add(csum_sub(~(skb->csum), fsum),
239					      tsum);
240		}
241	} else {
242		sum = ~csum_fold(csum_add(csum_sub(csum_unfold(sum), fsum),
243					  tsum));
244	}
245
246	if (!skb_make_writable(skb, l4csum_offset + sizeof(sum)) ||
247	    skb_store_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
248		return -1;
249
250	return 0;
251}
252
253static int nft_payload_csum_inet(struct sk_buff *skb, const u32 *src,
254				 __wsum fsum, __wsum tsum, int csum_offset)
255{
256	__sum16 sum;
257
258	if (skb_copy_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
259		return -1;
260
261	nft_csum_replace(&sum, fsum, tsum);
262	if (!skb_make_writable(skb, csum_offset + sizeof(sum)) ||
263	    skb_store_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
264		return -1;
265
266	return 0;
267}
268
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
269static void nft_payload_set_eval(const struct nft_expr *expr,
270				 struct nft_regs *regs,
271				 const struct nft_pktinfo *pkt)
272{
273	const struct nft_payload_set *priv = nft_expr_priv(expr);
274	struct sk_buff *skb = pkt->skb;
275	const u32 *src = &regs->data[priv->sreg];
276	int offset, csum_offset;
 
277	__wsum fsum, tsum;
278
279	switch (priv->base) {
280	case NFT_PAYLOAD_LL_HEADER:
281		if (!skb_mac_header_was_set(skb))
282			goto err;
283		offset = skb_mac_header(skb) - skb->data;
 
 
 
 
 
 
 
 
 
 
 
 
284		break;
285	case NFT_PAYLOAD_NETWORK_HEADER:
286		offset = skb_network_offset(skb);
287		break;
288	case NFT_PAYLOAD_TRANSPORT_HEADER:
289		if (!pkt->tprot_set)
 
 
 
 
 
 
290			goto err;
291		offset = pkt->xt.thoff;
292		break;
293	default:
294		BUG();
 
295	}
296
297	csum_offset = offset + priv->csum_offset;
298	offset += priv->offset;
299
300	if ((priv->csum_type == NFT_PAYLOAD_CSUM_INET || priv->csum_flags) &&
301	    (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER ||
 
302	     skb->ip_summed != CHECKSUM_PARTIAL)) {
 
 
 
303		fsum = skb_checksum(skb, offset, priv->len, 0);
304		tsum = csum_partial(src, priv->len, 0);
305
306		if (priv->csum_type == NFT_PAYLOAD_CSUM_INET &&
307		    nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))
308			goto err;
309
310		if (priv->csum_flags &&
311		    nft_payload_l4csum_update(pkt, skb, fsum, tsum) < 0)
312			goto err;
313	}
314
315	if (!skb_make_writable(skb, max(offset + priv->len, 0)) ||
316	    skb_store_bits(skb, offset, src, priv->len) < 0)
317		goto err;
318
 
 
 
 
 
 
 
 
319	return;
320err:
321	regs->verdict.code = NFT_BREAK;
322}
323
324static int nft_payload_set_init(const struct nft_ctx *ctx,
325				const struct nft_expr *expr,
326				const struct nlattr * const tb[])
327{
328	struct nft_payload_set *priv = nft_expr_priv(expr);
 
 
329
330	priv->base        = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
331	priv->offset      = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
332	priv->len         = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
333	priv->sreg        = nft_parse_register(tb[NFTA_PAYLOAD_SREG]);
334
335	if (tb[NFTA_PAYLOAD_CSUM_TYPE])
336		priv->csum_type =
337			ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_TYPE]));
338	if (tb[NFTA_PAYLOAD_CSUM_OFFSET])
339		priv->csum_offset =
340			ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_OFFSET]));
 
 
 
 
341	if (tb[NFTA_PAYLOAD_CSUM_FLAGS]) {
342		u32 flags;
343
344		flags = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_FLAGS]));
345		if (flags & ~NFT_PAYLOAD_L4CSUM_PSEUDOHDR)
346			return -EINVAL;
347
348		priv->csum_flags = flags;
349	}
350
351	switch (priv->csum_type) {
352	case NFT_PAYLOAD_CSUM_NONE:
353	case NFT_PAYLOAD_CSUM_INET:
354		break;
 
 
 
 
 
 
 
355	default:
356		return -EOPNOTSUPP;
357	}
 
358
359	return nft_validate_register_load(priv->sreg, priv->len);
 
360}
361
362static int nft_payload_set_dump(struct sk_buff *skb, const struct nft_expr *expr)
 
363{
364	const struct nft_payload_set *priv = nft_expr_priv(expr);
365
366	if (nft_dump_register(skb, NFTA_PAYLOAD_SREG, priv->sreg) ||
367	    nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
368	    nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
369	    nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)) ||
370	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_TYPE, htonl(priv->csum_type)) ||
371	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_OFFSET,
372			 htonl(priv->csum_offset)) ||
373	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_FLAGS, htonl(priv->csum_flags)))
374		goto nla_put_failure;
375	return 0;
376
377nla_put_failure:
378	return -1;
379}
380
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
381static const struct nft_expr_ops nft_payload_set_ops = {
382	.type		= &nft_payload_type,
383	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),
384	.eval		= nft_payload_set_eval,
385	.init		= nft_payload_set_init,
386	.dump		= nft_payload_set_dump,
 
387};
388
389static const struct nft_expr_ops *
390nft_payload_select_ops(const struct nft_ctx *ctx,
391		       const struct nlattr * const tb[])
392{
393	enum nft_payload_bases base;
394	unsigned int offset, len;
 
395
396	if (tb[NFTA_PAYLOAD_BASE] == NULL ||
397	    tb[NFTA_PAYLOAD_OFFSET] == NULL ||
398	    tb[NFTA_PAYLOAD_LEN] == NULL)
399		return ERR_PTR(-EINVAL);
400
401	base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
402	switch (base) {
403	case NFT_PAYLOAD_LL_HEADER:
404	case NFT_PAYLOAD_NETWORK_HEADER:
405	case NFT_PAYLOAD_TRANSPORT_HEADER:
 
406		break;
407	default:
408		return ERR_PTR(-EOPNOTSUPP);
409	}
410
411	if (tb[NFTA_PAYLOAD_SREG] != NULL) {
412		if (tb[NFTA_PAYLOAD_DREG] != NULL)
413			return ERR_PTR(-EINVAL);
414		return &nft_payload_set_ops;
415	}
416
417	if (tb[NFTA_PAYLOAD_DREG] == NULL)
418		return ERR_PTR(-EINVAL);
419
420	offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
421	len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
 
 
 
 
 
422
423	if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
424	    base != NFT_PAYLOAD_LL_HEADER)
425		return &nft_payload_fast_ops;
426	else
427		return &nft_payload_ops;
428}
429
430struct nft_expr_type nft_payload_type __read_mostly = {
431	.name		= "payload",
432	.select_ops	= nft_payload_select_ops,
 
433	.policy		= nft_payload_policy,
434	.maxattr	= NFTA_PAYLOAD_MAX,
435	.owner		= THIS_MODULE,
436};
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
   4 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
   5 *
 
 
 
 
   6 * Development of this code funded by Astaro AG (http://www.astaro.com/)
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/if_vlan.h>
  11#include <linux/init.h>
  12#include <linux/module.h>
  13#include <linux/netlink.h>
  14#include <linux/netfilter.h>
  15#include <linux/netfilter/nf_tables.h>
  16#include <net/netfilter/nf_tables_core.h>
  17#include <net/netfilter/nf_tables.h>
  18#include <net/netfilter/nf_tables_offload.h>
  19/* For layer 4 checksum field offset. */
  20#include <linux/tcp.h>
  21#include <linux/udp.h>
  22#include <net/gre.h>
  23#include <linux/icmpv6.h>
  24#include <linux/ip.h>
  25#include <linux/ipv6.h>
  26#include <net/sctp/checksum.h>
  27
  28static bool nft_payload_rebuild_vlan_hdr(const struct sk_buff *skb, int mac_off,
  29					 struct vlan_ethhdr *veth)
  30{
  31	if (skb_copy_bits(skb, mac_off, veth, ETH_HLEN))
  32		return false;
  33
  34	veth->h_vlan_proto = skb->vlan_proto;
  35	veth->h_vlan_TCI = htons(skb_vlan_tag_get(skb));
  36	veth->h_vlan_encapsulated_proto = skb->protocol;
  37
  38	return true;
  39}
  40
  41/* add vlan header into the user buffer for if tag was removed by offloads */
  42static bool
  43nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
  44{
  45	int mac_off = skb_mac_header(skb) - skb->data;
  46	u8 *vlanh, *dst_u8 = (u8 *) d;
  47	struct vlan_ethhdr veth;
  48
  49	vlanh = (u8 *) &veth;
  50	if (offset < VLAN_ETH_HLEN) {
  51		u8 ethlen = len;
  52
  53		if (!nft_payload_rebuild_vlan_hdr(skb, mac_off, &veth))
  54			return false;
  55
  56		if (offset + len > VLAN_ETH_HLEN)
  57			ethlen -= offset + len - VLAN_ETH_HLEN;
  58
  59		memcpy(dst_u8, vlanh + offset, ethlen);
  60
  61		len -= ethlen;
  62		if (len == 0)
  63			return true;
  64
  65		dst_u8 += ethlen;
  66		offset = ETH_HLEN;
  67	} else {
  68		offset -= VLAN_HLEN;
 
  69	}
  70
  71	return skb_copy_bits(skb, offset + mac_off, dst_u8, len) == 0;
  72}
  73
  74static int __nft_payload_inner_offset(struct nft_pktinfo *pkt)
  75{
  76	unsigned int thoff = nft_thoff(pkt);
  77
  78	if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff)
  79		return -1;
  80
  81	switch (pkt->tprot) {
  82	case IPPROTO_UDP:
  83		pkt->inneroff = thoff + sizeof(struct udphdr);
  84		break;
  85	case IPPROTO_TCP: {
  86		struct tcphdr *th, _tcph;
  87
  88		th = skb_header_pointer(pkt->skb, thoff, sizeof(_tcph), &_tcph);
  89		if (!th)
  90			return -1;
  91
  92		pkt->inneroff = thoff + __tcp_hdrlen(th);
  93		}
  94		break;
  95	case IPPROTO_GRE: {
  96		u32 offset = sizeof(struct gre_base_hdr);
  97		struct gre_base_hdr *gre, _gre;
  98		__be16 version;
  99
 100		gre = skb_header_pointer(pkt->skb, thoff, sizeof(_gre), &_gre);
 101		if (!gre)
 102			return -1;
 103
 104		version = gre->flags & GRE_VERSION;
 105		switch (version) {
 106		case GRE_VERSION_0:
 107			if (gre->flags & GRE_ROUTING)
 108				return -1;
 109
 110			if (gre->flags & GRE_CSUM) {
 111				offset += sizeof_field(struct gre_full_hdr, csum) +
 112					  sizeof_field(struct gre_full_hdr, reserved1);
 113			}
 114			if (gre->flags & GRE_KEY)
 115				offset += sizeof_field(struct gre_full_hdr, key);
 116
 117			if (gre->flags & GRE_SEQ)
 118				offset += sizeof_field(struct gre_full_hdr, seq);
 119			break;
 120		default:
 121			return -1;
 122		}
 123
 124		pkt->inneroff = thoff + offset;
 125		}
 126		break;
 127	case IPPROTO_IPIP:
 128		pkt->inneroff = thoff;
 129		break;
 130	default:
 131		return -1;
 132	}
 133
 134	pkt->flags |= NFT_PKTINFO_INNER;
 135
 136	return 0;
 137}
 138
 139int nft_payload_inner_offset(const struct nft_pktinfo *pkt)
 140{
 141	if (!(pkt->flags & NFT_PKTINFO_INNER) &&
 142	    __nft_payload_inner_offset((struct nft_pktinfo *)pkt) < 0)
 143		return -1;
 144
 145	return pkt->inneroff;
 146}
 147
 148static bool nft_payload_need_vlan_adjust(u32 offset, u32 len)
 149{
 150	unsigned int boundary = offset + len;
 151
 152	/* data past ether src/dst requested, copy needed */
 153	if (boundary > offsetof(struct ethhdr, h_proto))
 154		return true;
 155
 156	return false;
 
 
 157}
 158
 159void nft_payload_eval(const struct nft_expr *expr,
 160		      struct nft_regs *regs,
 161		      const struct nft_pktinfo *pkt)
 162{
 163	const struct nft_payload *priv = nft_expr_priv(expr);
 164	const struct sk_buff *skb = pkt->skb;
 165	u32 *dest = &regs->data[priv->dreg];
 166	int offset;
 167
 168	if (priv->len % NFT_REG32_SIZE)
 169		dest[priv->len / NFT_REG32_SIZE] = 0;
 170
 171	switch (priv->base) {
 172	case NFT_PAYLOAD_LL_HEADER:
 173		if (!skb_mac_header_was_set(skb) || skb_mac_header_len(skb) == 0)
 174			goto err;
 175
 176		if (skb_vlan_tag_present(skb) &&
 177		    nft_payload_need_vlan_adjust(priv->offset, priv->len)) {
 178			if (!nft_payload_copy_vlan(dest, skb,
 179						   priv->offset, priv->len))
 180				goto err;
 181			return;
 182		}
 183		offset = skb_mac_header(skb) - skb->data;
 184		break;
 185	case NFT_PAYLOAD_NETWORK_HEADER:
 186		offset = skb_network_offset(skb);
 187		break;
 188	case NFT_PAYLOAD_TRANSPORT_HEADER:
 189		if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff)
 190			goto err;
 191		offset = nft_thoff(pkt);
 192		break;
 193	case NFT_PAYLOAD_INNER_HEADER:
 194		offset = nft_payload_inner_offset(pkt);
 195		if (offset < 0)
 196			goto err;
 
 197		break;
 198	default:
 199		WARN_ON_ONCE(1);
 200		goto err;
 201	}
 202	offset += priv->offset;
 203
 204	if (skb_copy_bits(skb, offset, dest, priv->len) < 0)
 205		goto err;
 206	return;
 207err:
 208	regs->verdict.code = NFT_BREAK;
 209}
 210
 211static const struct nla_policy nft_payload_policy[NFTA_PAYLOAD_MAX + 1] = {
 212	[NFTA_PAYLOAD_SREG]		= { .type = NLA_U32 },
 213	[NFTA_PAYLOAD_DREG]		= { .type = NLA_U32 },
 214	[NFTA_PAYLOAD_BASE]		= { .type = NLA_U32 },
 215	[NFTA_PAYLOAD_OFFSET]		= NLA_POLICY_MAX(NLA_BE32, 255),
 216	[NFTA_PAYLOAD_LEN]		= NLA_POLICY_MAX(NLA_BE32, 255),
 217	[NFTA_PAYLOAD_CSUM_TYPE]	= { .type = NLA_U32 },
 218	[NFTA_PAYLOAD_CSUM_OFFSET]	= NLA_POLICY_MAX(NLA_BE32, 255),
 219	[NFTA_PAYLOAD_CSUM_FLAGS]	= { .type = NLA_U32 },
 220};
 221
 222static int nft_payload_init(const struct nft_ctx *ctx,
 223			    const struct nft_expr *expr,
 224			    const struct nlattr * const tb[])
 225{
 226	struct nft_payload *priv = nft_expr_priv(expr);
 227
 228	priv->base   = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
 229	priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
 230	priv->len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
 
 231
 232	return nft_parse_register_store(ctx, tb[NFTA_PAYLOAD_DREG],
 233					&priv->dreg, NULL, NFT_DATA_VALUE,
 234					priv->len);
 235}
 236
 237static int nft_payload_dump(struct sk_buff *skb,
 238			    const struct nft_expr *expr, bool reset)
 239{
 240	const struct nft_payload *priv = nft_expr_priv(expr);
 241
 242	if (nft_dump_register(skb, NFTA_PAYLOAD_DREG, priv->dreg) ||
 243	    nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
 244	    nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
 245	    nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)))
 246		goto nla_put_failure;
 247	return 0;
 248
 249nla_put_failure:
 250	return -1;
 251}
 252
 253static bool nft_payload_reduce(struct nft_regs_track *track,
 254			       const struct nft_expr *expr)
 255{
 256	const struct nft_payload *priv = nft_expr_priv(expr);
 257	const struct nft_payload *payload;
 258
 259	if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
 260		nft_reg_track_update(track, expr, priv->dreg, priv->len);
 261		return false;
 262	}
 263
 264	payload = nft_expr_priv(track->regs[priv->dreg].selector);
 265	if (priv->base != payload->base ||
 266	    priv->offset != payload->offset ||
 267	    priv->len != payload->len) {
 268		nft_reg_track_update(track, expr, priv->dreg, priv->len);
 269		return false;
 270	}
 271
 272	if (!track->regs[priv->dreg].bitwise)
 273		return true;
 274
 275	return nft_expr_reduce_bitwise(track, expr);
 276}
 277
 278static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
 279				     u32 priv_len, u32 field_len)
 280{
 281	unsigned int remainder, delta, k;
 282	struct nft_data mask = {};
 283	__be32 remainder_mask;
 284
 285	if (priv_len == field_len) {
 286		memset(&reg->mask, 0xff, priv_len);
 287		return true;
 288	} else if (priv_len > field_len) {
 289		return false;
 290	}
 291
 292	memset(&mask, 0xff, field_len);
 293	remainder = priv_len % sizeof(u32);
 294	if (remainder) {
 295		k = priv_len / sizeof(u32);
 296		delta = field_len - priv_len;
 297		remainder_mask = htonl(~((1 << (delta * BITS_PER_BYTE)) - 1));
 298		mask.data[k] = (__force u32)remainder_mask;
 299	}
 300
 301	memcpy(&reg->mask, &mask, field_len);
 302
 303	return true;
 304}
 305
 306static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 307				  struct nft_flow_rule *flow,
 308				  const struct nft_payload *priv)
 309{
 310	struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 311
 312	switch (priv->offset) {
 313	case offsetof(struct ethhdr, h_source):
 314		if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
 315			return -EOPNOTSUPP;
 316
 317		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
 318				  src, ETH_ALEN, reg);
 319		break;
 320	case offsetof(struct ethhdr, h_dest):
 321		if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
 322			return -EOPNOTSUPP;
 323
 324		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
 325				  dst, ETH_ALEN, reg);
 326		break;
 327	case offsetof(struct ethhdr, h_proto):
 328		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 329			return -EOPNOTSUPP;
 330
 331		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic,
 332				  n_proto, sizeof(__be16), reg);
 333		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 334		break;
 335	case offsetof(struct vlan_ethhdr, h_vlan_TCI):
 336		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 337			return -EOPNOTSUPP;
 338
 339		NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_VLAN, vlan,
 340					vlan_tci, sizeof(__be16), reg,
 341					NFT_OFFLOAD_F_NETWORK2HOST);
 342		break;
 343	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
 344		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 345			return -EOPNOTSUPP;
 346
 347		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
 348				  vlan_tpid, sizeof(__be16), reg);
 349		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 350		break;
 351	case offsetof(struct vlan_ethhdr, h_vlan_TCI) + sizeof(struct vlan_hdr):
 352		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 353			return -EOPNOTSUPP;
 354
 355		NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 356					vlan_tci, sizeof(__be16), reg,
 357					NFT_OFFLOAD_F_NETWORK2HOST);
 358		break;
 359	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
 360							sizeof(struct vlan_hdr):
 361		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 362			return -EOPNOTSUPP;
 363
 364		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 365				  vlan_tpid, sizeof(__be16), reg);
 366		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 367		break;
 368	default:
 369		return -EOPNOTSUPP;
 370	}
 371
 372	return 0;
 373}
 374
 375static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
 376				  struct nft_flow_rule *flow,
 377				  const struct nft_payload *priv)
 378{
 379	struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 380
 381	switch (priv->offset) {
 382	case offsetof(struct iphdr, saddr):
 383		if (!nft_payload_offload_mask(reg, priv->len,
 384					      sizeof(struct in_addr)))
 385			return -EOPNOTSUPP;
 386
 387		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
 388				  sizeof(struct in_addr), reg);
 389		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 390		break;
 391	case offsetof(struct iphdr, daddr):
 392		if (!nft_payload_offload_mask(reg, priv->len,
 393					      sizeof(struct in_addr)))
 394			return -EOPNOTSUPP;
 395
 396		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
 397				  sizeof(struct in_addr), reg);
 398		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
 399		break;
 400	case offsetof(struct iphdr, protocol):
 401		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
 402			return -EOPNOTSUPP;
 403
 404		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
 405				  sizeof(__u8), reg);
 406		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
 407		break;
 408	default:
 409		return -EOPNOTSUPP;
 410	}
 411
 412	return 0;
 413}
 414
 415static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
 416				  struct nft_flow_rule *flow,
 417				  const struct nft_payload *priv)
 418{
 419	struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 420
 421	switch (priv->offset) {
 422	case offsetof(struct ipv6hdr, saddr):
 423		if (!nft_payload_offload_mask(reg, priv->len,
 424					      sizeof(struct in6_addr)))
 425			return -EOPNOTSUPP;
 426
 427		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
 428				  sizeof(struct in6_addr), reg);
 429		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 430		break;
 431	case offsetof(struct ipv6hdr, daddr):
 432		if (!nft_payload_offload_mask(reg, priv->len,
 433					      sizeof(struct in6_addr)))
 434			return -EOPNOTSUPP;
 435
 436		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
 437				  sizeof(struct in6_addr), reg);
 438		nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
 439		break;
 440	case offsetof(struct ipv6hdr, nexthdr):
 441		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
 442			return -EOPNOTSUPP;
 443
 444		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
 445				  sizeof(__u8), reg);
 446		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
 447		break;
 448	default:
 449		return -EOPNOTSUPP;
 450	}
 451
 452	return 0;
 453}
 454
 455static int nft_payload_offload_nh(struct nft_offload_ctx *ctx,
 456				  struct nft_flow_rule *flow,
 457				  const struct nft_payload *priv)
 458{
 459	int err;
 460
 461	switch (ctx->dep.l3num) {
 462	case htons(ETH_P_IP):
 463		err = nft_payload_offload_ip(ctx, flow, priv);
 464		break;
 465	case htons(ETH_P_IPV6):
 466		err = nft_payload_offload_ip6(ctx, flow, priv);
 467		break;
 468	default:
 469		return -EOPNOTSUPP;
 470	}
 471
 472	return err;
 473}
 474
 475static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx,
 476				   struct nft_flow_rule *flow,
 477				   const struct nft_payload *priv)
 478{
 479	struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 480
 481	switch (priv->offset) {
 482	case offsetof(struct tcphdr, source):
 483		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 484			return -EOPNOTSUPP;
 485
 486		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
 487				  sizeof(__be16), reg);
 488		break;
 489	case offsetof(struct tcphdr, dest):
 490		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 491			return -EOPNOTSUPP;
 492
 493		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
 494				  sizeof(__be16), reg);
 495		break;
 496	default:
 497		return -EOPNOTSUPP;
 498	}
 499
 500	return 0;
 501}
 502
 503static int nft_payload_offload_udp(struct nft_offload_ctx *ctx,
 504				   struct nft_flow_rule *flow,
 505				   const struct nft_payload *priv)
 506{
 507	struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
 508
 509	switch (priv->offset) {
 510	case offsetof(struct udphdr, source):
 511		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 512			return -EOPNOTSUPP;
 513
 514		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
 515				  sizeof(__be16), reg);
 516		break;
 517	case offsetof(struct udphdr, dest):
 518		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 519			return -EOPNOTSUPP;
 520
 521		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
 522				  sizeof(__be16), reg);
 523		break;
 524	default:
 525		return -EOPNOTSUPP;
 526	}
 527
 528	return 0;
 529}
 530
 531static int nft_payload_offload_th(struct nft_offload_ctx *ctx,
 532				  struct nft_flow_rule *flow,
 533				  const struct nft_payload *priv)
 534{
 535	int err;
 536
 537	switch (ctx->dep.protonum) {
 538	case IPPROTO_TCP:
 539		err = nft_payload_offload_tcp(ctx, flow, priv);
 540		break;
 541	case IPPROTO_UDP:
 542		err = nft_payload_offload_udp(ctx, flow, priv);
 543		break;
 544	default:
 545		return -EOPNOTSUPP;
 546	}
 547
 548	return err;
 549}
 550
 551static int nft_payload_offload(struct nft_offload_ctx *ctx,
 552			       struct nft_flow_rule *flow,
 553			       const struct nft_expr *expr)
 554{
 555	const struct nft_payload *priv = nft_expr_priv(expr);
 556	int err;
 557
 558	switch (priv->base) {
 559	case NFT_PAYLOAD_LL_HEADER:
 560		err = nft_payload_offload_ll(ctx, flow, priv);
 561		break;
 562	case NFT_PAYLOAD_NETWORK_HEADER:
 563		err = nft_payload_offload_nh(ctx, flow, priv);
 564		break;
 565	case NFT_PAYLOAD_TRANSPORT_HEADER:
 566		err = nft_payload_offload_th(ctx, flow, priv);
 567		break;
 568	default:
 569		err = -EOPNOTSUPP;
 570		break;
 571	}
 572	return err;
 573}
 574
 575static const struct nft_expr_ops nft_payload_ops = {
 576	.type		= &nft_payload_type,
 577	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload)),
 578	.eval		= nft_payload_eval,
 579	.init		= nft_payload_init,
 580	.dump		= nft_payload_dump,
 581	.reduce		= nft_payload_reduce,
 582	.offload	= nft_payload_offload,
 583};
 584
 585const struct nft_expr_ops nft_payload_fast_ops = {
 586	.type		= &nft_payload_type,
 587	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload)),
 588	.eval		= nft_payload_eval,
 589	.init		= nft_payload_init,
 590	.dump		= nft_payload_dump,
 591	.reduce		= nft_payload_reduce,
 592	.offload	= nft_payload_offload,
 593};
 594
 595void nft_payload_inner_eval(const struct nft_expr *expr, struct nft_regs *regs,
 596			    const struct nft_pktinfo *pkt,
 597			    struct nft_inner_tun_ctx *tun_ctx)
 598{
 599	const struct nft_payload *priv = nft_expr_priv(expr);
 600	const struct sk_buff *skb = pkt->skb;
 601	u32 *dest = &regs->data[priv->dreg];
 602	int offset;
 603
 604	if (priv->len % NFT_REG32_SIZE)
 605		dest[priv->len / NFT_REG32_SIZE] = 0;
 606
 607	switch (priv->base) {
 608	case NFT_PAYLOAD_TUN_HEADER:
 609		if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_TUN))
 610			goto err;
 611
 612		offset = tun_ctx->inner_tunoff;
 613		break;
 614	case NFT_PAYLOAD_LL_HEADER:
 615		if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_LL))
 616			goto err;
 617
 618		offset = tun_ctx->inner_lloff;
 619		break;
 620	case NFT_PAYLOAD_NETWORK_HEADER:
 621		if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_NH))
 622			goto err;
 623
 624		offset = tun_ctx->inner_nhoff;
 625		break;
 626	case NFT_PAYLOAD_TRANSPORT_HEADER:
 627		if (!(tun_ctx->flags & NFT_PAYLOAD_CTX_INNER_TH))
 628			goto err;
 629
 630		offset = tun_ctx->inner_thoff;
 631		break;
 632	default:
 633		WARN_ON_ONCE(1);
 634		goto err;
 635	}
 636	offset += priv->offset;
 637
 638	if (skb_copy_bits(skb, offset, dest, priv->len) < 0)
 639		goto err;
 640
 641	return;
 642err:
 643	regs->verdict.code = NFT_BREAK;
 644}
 645
 646static int nft_payload_inner_init(const struct nft_ctx *ctx,
 647				  const struct nft_expr *expr,
 648				  const struct nlattr * const tb[])
 649{
 650	struct nft_payload *priv = nft_expr_priv(expr);
 651	u32 base;
 652
 653	if (!tb[NFTA_PAYLOAD_BASE] || !tb[NFTA_PAYLOAD_OFFSET] ||
 654	    !tb[NFTA_PAYLOAD_LEN] || !tb[NFTA_PAYLOAD_DREG])
 655		return -EINVAL;
 656
 657	base   = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
 658	switch (base) {
 659	case NFT_PAYLOAD_TUN_HEADER:
 660	case NFT_PAYLOAD_LL_HEADER:
 661	case NFT_PAYLOAD_NETWORK_HEADER:
 662	case NFT_PAYLOAD_TRANSPORT_HEADER:
 663		break;
 664	default:
 665		return -EOPNOTSUPP;
 666	}
 667
 668	priv->base   = base;
 669	priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
 670	priv->len    = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
 671
 672	return nft_parse_register_store(ctx, tb[NFTA_PAYLOAD_DREG],
 673					&priv->dreg, NULL, NFT_DATA_VALUE,
 674					priv->len);
 675}
 676
 677static const struct nft_expr_ops nft_payload_inner_ops = {
 678	.type		= &nft_payload_type,
 679	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload)),
 680	.init		= nft_payload_inner_init,
 681	.dump		= nft_payload_dump,
 682	/* direct call to nft_payload_inner_eval(). */
 683};
 684
 685static inline void nft_csum_replace(__sum16 *sum, __wsum fsum, __wsum tsum)
 686{
 687	*sum = csum_fold(csum_add(csum_sub(~csum_unfold(*sum), fsum), tsum));
 688	if (*sum == 0)
 689		*sum = CSUM_MANGLED_0;
 690}
 691
 692static bool nft_payload_udp_checksum(struct sk_buff *skb, unsigned int thoff)
 693{
 694	struct udphdr *uh, _uh;
 695
 696	uh = skb_header_pointer(skb, thoff, sizeof(_uh), &_uh);
 697	if (!uh)
 698		return false;
 699
 700	return (__force bool)uh->check;
 701}
 702
 703static int nft_payload_l4csum_offset(const struct nft_pktinfo *pkt,
 704				     struct sk_buff *skb,
 705				     unsigned int *l4csum_offset)
 706{
 707	if (pkt->fragoff)
 708		return -1;
 709
 710	switch (pkt->tprot) {
 711	case IPPROTO_TCP:
 712		*l4csum_offset = offsetof(struct tcphdr, check);
 713		break;
 714	case IPPROTO_UDP:
 715		if (!nft_payload_udp_checksum(skb, nft_thoff(pkt)))
 716			return -1;
 717		fallthrough;
 718	case IPPROTO_UDPLITE:
 719		*l4csum_offset = offsetof(struct udphdr, check);
 720		break;
 721	case IPPROTO_ICMPV6:
 722		*l4csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
 723		break;
 724	default:
 725		return -1;
 726	}
 727
 728	*l4csum_offset += nft_thoff(pkt);
 729	return 0;
 730}
 731
 732static int nft_payload_csum_sctp(struct sk_buff *skb, int offset)
 733{
 734	struct sctphdr *sh;
 735
 736	if (skb_ensure_writable(skb, offset + sizeof(*sh)))
 737		return -1;
 738
 739	sh = (struct sctphdr *)(skb->data + offset);
 740	sh->checksum = sctp_compute_cksum(skb, offset);
 741	skb->ip_summed = CHECKSUM_UNNECESSARY;
 742	return 0;
 743}
 744
 745static int nft_payload_l4csum_update(const struct nft_pktinfo *pkt,
 746				     struct sk_buff *skb,
 747				     __wsum fsum, __wsum tsum)
 748{
 749	int l4csum_offset;
 750	__sum16 sum;
 751
 752	/* If we cannot determine layer 4 checksum offset or this packet doesn't
 753	 * require layer 4 checksum recalculation, skip this packet.
 754	 */
 755	if (nft_payload_l4csum_offset(pkt, skb, &l4csum_offset) < 0)
 756		return 0;
 757
 758	if (skb_copy_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
 759		return -1;
 760
 761	/* Checksum mangling for an arbitrary amount of bytes, based on
 762	 * inet_proto_csum_replace*() functions.
 763	 */
 764	if (skb->ip_summed != CHECKSUM_PARTIAL) {
 765		nft_csum_replace(&sum, fsum, tsum);
 766		if (skb->ip_summed == CHECKSUM_COMPLETE) {
 767			skb->csum = ~csum_add(csum_sub(~(skb->csum), fsum),
 768					      tsum);
 769		}
 770	} else {
 771		sum = ~csum_fold(csum_add(csum_sub(csum_unfold(sum), fsum),
 772					  tsum));
 773	}
 774
 775	if (skb_ensure_writable(skb, l4csum_offset + sizeof(sum)) ||
 776	    skb_store_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
 777		return -1;
 778
 779	return 0;
 780}
 781
 782static int nft_payload_csum_inet(struct sk_buff *skb, const u32 *src,
 783				 __wsum fsum, __wsum tsum, int csum_offset)
 784{
 785	__sum16 sum;
 786
 787	if (skb_copy_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
 788		return -1;
 789
 790	nft_csum_replace(&sum, fsum, tsum);
 791	if (skb_ensure_writable(skb, csum_offset + sizeof(sum)) ||
 792	    skb_store_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
 793		return -1;
 794
 795	return 0;
 796}
 797
 798struct nft_payload_set {
 799	enum nft_payload_bases	base:8;
 800	u8			offset;
 801	u8			len;
 802	u8			sreg;
 803	u8			csum_type;
 804	u8			csum_offset;
 805	u8			csum_flags;
 806};
 807
 808/* This is not struct vlan_hdr. */
 809struct nft_payload_vlan_hdr {
 810	__be16			h_vlan_proto;
 811	__be16			h_vlan_TCI;
 812};
 813
 814static bool
 815nft_payload_set_vlan(const u32 *src, struct sk_buff *skb, u8 offset, u8 len,
 816		     int *vlan_hlen)
 817{
 818	struct nft_payload_vlan_hdr *vlanh;
 819	__be16 vlan_proto;
 820	u16 vlan_tci;
 821
 822	if (offset >= offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto)) {
 823		*vlan_hlen = VLAN_HLEN;
 824		return true;
 825	}
 826
 827	switch (offset) {
 828	case offsetof(struct vlan_ethhdr, h_vlan_proto):
 829		if (len == 2) {
 830			vlan_proto = nft_reg_load_be16(src);
 831			skb->vlan_proto = vlan_proto;
 832		} else if (len == 4) {
 833			vlanh = (struct nft_payload_vlan_hdr *)src;
 834			__vlan_hwaccel_put_tag(skb, vlanh->h_vlan_proto,
 835					       ntohs(vlanh->h_vlan_TCI));
 836		} else {
 837			return false;
 838		}
 839		break;
 840	case offsetof(struct vlan_ethhdr, h_vlan_TCI):
 841		if (len != 2)
 842			return false;
 843
 844		vlan_tci = ntohs(nft_reg_load_be16(src));
 845		skb->vlan_tci = vlan_tci;
 846		break;
 847	default:
 848		return false;
 849	}
 850
 851	return true;
 852}
 853
 854static void nft_payload_set_eval(const struct nft_expr *expr,
 855				 struct nft_regs *regs,
 856				 const struct nft_pktinfo *pkt)
 857{
 858	const struct nft_payload_set *priv = nft_expr_priv(expr);
 
 859	const u32 *src = &regs->data[priv->sreg];
 860	int offset, csum_offset, vlan_hlen = 0;
 861	struct sk_buff *skb = pkt->skb;
 862	__wsum fsum, tsum;
 863
 864	switch (priv->base) {
 865	case NFT_PAYLOAD_LL_HEADER:
 866		if (!skb_mac_header_was_set(skb))
 867			goto err;
 868
 869		if (skb_vlan_tag_present(skb) &&
 870		    nft_payload_need_vlan_adjust(priv->offset, priv->len)) {
 871			if (!nft_payload_set_vlan(src, skb,
 872						  priv->offset, priv->len,
 873						  &vlan_hlen))
 874				goto err;
 875
 876			if (!vlan_hlen)
 877				return;
 878		}
 879
 880		offset = skb_mac_header(skb) - skb->data - vlan_hlen;
 881		break;
 882	case NFT_PAYLOAD_NETWORK_HEADER:
 883		offset = skb_network_offset(skb);
 884		break;
 885	case NFT_PAYLOAD_TRANSPORT_HEADER:
 886		if (!(pkt->flags & NFT_PKTINFO_L4PROTO) || pkt->fragoff)
 887			goto err;
 888		offset = nft_thoff(pkt);
 889		break;
 890	case NFT_PAYLOAD_INNER_HEADER:
 891		offset = nft_payload_inner_offset(pkt);
 892		if (offset < 0)
 893			goto err;
 
 894		break;
 895	default:
 896		WARN_ON_ONCE(1);
 897		goto err;
 898	}
 899
 900	csum_offset = offset + priv->csum_offset;
 901	offset += priv->offset;
 902
 903	if ((priv->csum_type == NFT_PAYLOAD_CSUM_INET || priv->csum_flags) &&
 904	    ((priv->base != NFT_PAYLOAD_TRANSPORT_HEADER &&
 905	      priv->base != NFT_PAYLOAD_INNER_HEADER) ||
 906	     skb->ip_summed != CHECKSUM_PARTIAL)) {
 907		if (offset + priv->len > skb->len)
 908			goto err;
 909
 910		fsum = skb_checksum(skb, offset, priv->len, 0);
 911		tsum = csum_partial(src, priv->len, 0);
 912
 913		if (priv->csum_type == NFT_PAYLOAD_CSUM_INET &&
 914		    nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))
 915			goto err;
 916
 917		if (priv->csum_flags &&
 918		    nft_payload_l4csum_update(pkt, skb, fsum, tsum) < 0)
 919			goto err;
 920	}
 921
 922	if (skb_ensure_writable(skb, max(offset + priv->len, 0)) ||
 923	    skb_store_bits(skb, offset, src, priv->len) < 0)
 924		goto err;
 925
 926	if (priv->csum_type == NFT_PAYLOAD_CSUM_SCTP &&
 927	    pkt->tprot == IPPROTO_SCTP &&
 928	    skb->ip_summed != CHECKSUM_PARTIAL) {
 929		if (pkt->fragoff == 0 &&
 930		    nft_payload_csum_sctp(skb, nft_thoff(pkt)))
 931			goto err;
 932	}
 933
 934	return;
 935err:
 936	regs->verdict.code = NFT_BREAK;
 937}
 938
 939static int nft_payload_set_init(const struct nft_ctx *ctx,
 940				const struct nft_expr *expr,
 941				const struct nlattr * const tb[])
 942{
 943	struct nft_payload_set *priv = nft_expr_priv(expr);
 944	u32 csum_offset, csum_type = NFT_PAYLOAD_CSUM_NONE;
 945	int err;
 946
 947	priv->base        = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
 948	priv->offset      = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
 949	priv->len         = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
 
 950
 951	if (tb[NFTA_PAYLOAD_CSUM_TYPE])
 952		csum_type = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_TYPE]));
 953	if (tb[NFTA_PAYLOAD_CSUM_OFFSET]) {
 954		err = nft_parse_u32_check(tb[NFTA_PAYLOAD_CSUM_OFFSET], U8_MAX,
 955					  &csum_offset);
 956		if (err < 0)
 957			return err;
 958
 959		priv->csum_offset = csum_offset;
 960	}
 961	if (tb[NFTA_PAYLOAD_CSUM_FLAGS]) {
 962		u32 flags;
 963
 964		flags = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_FLAGS]));
 965		if (flags & ~NFT_PAYLOAD_L4CSUM_PSEUDOHDR)
 966			return -EINVAL;
 967
 968		priv->csum_flags = flags;
 969	}
 970
 971	switch (csum_type) {
 972	case NFT_PAYLOAD_CSUM_NONE:
 973	case NFT_PAYLOAD_CSUM_INET:
 974		break;
 975	case NFT_PAYLOAD_CSUM_SCTP:
 976		if (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER)
 977			return -EINVAL;
 978
 979		if (priv->csum_offset != offsetof(struct sctphdr, checksum))
 980			return -EINVAL;
 981		break;
 982	default:
 983		return -EOPNOTSUPP;
 984	}
 985	priv->csum_type = csum_type;
 986
 987	return nft_parse_register_load(ctx, tb[NFTA_PAYLOAD_SREG], &priv->sreg,
 988				       priv->len);
 989}
 990
 991static int nft_payload_set_dump(struct sk_buff *skb,
 992				const struct nft_expr *expr, bool reset)
 993{
 994	const struct nft_payload_set *priv = nft_expr_priv(expr);
 995
 996	if (nft_dump_register(skb, NFTA_PAYLOAD_SREG, priv->sreg) ||
 997	    nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
 998	    nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
 999	    nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)) ||
1000	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_TYPE, htonl(priv->csum_type)) ||
1001	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_OFFSET,
1002			 htonl(priv->csum_offset)) ||
1003	    nla_put_be32(skb, NFTA_PAYLOAD_CSUM_FLAGS, htonl(priv->csum_flags)))
1004		goto nla_put_failure;
1005	return 0;
1006
1007nla_put_failure:
1008	return -1;
1009}
1010
1011static bool nft_payload_set_reduce(struct nft_regs_track *track,
1012				   const struct nft_expr *expr)
1013{
1014	int i;
1015
1016	for (i = 0; i < NFT_REG32_NUM; i++) {
1017		if (!track->regs[i].selector)
1018			continue;
1019
1020		if (track->regs[i].selector->ops != &nft_payload_ops &&
1021		    track->regs[i].selector->ops != &nft_payload_fast_ops)
1022			continue;
1023
1024		__nft_reg_track_cancel(track, i);
1025	}
1026
1027	return false;
1028}
1029
1030static const struct nft_expr_ops nft_payload_set_ops = {
1031	.type		= &nft_payload_type,
1032	.size		= NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),
1033	.eval		= nft_payload_set_eval,
1034	.init		= nft_payload_set_init,
1035	.dump		= nft_payload_set_dump,
1036	.reduce		= nft_payload_set_reduce,
1037};
1038
1039static const struct nft_expr_ops *
1040nft_payload_select_ops(const struct nft_ctx *ctx,
1041		       const struct nlattr * const tb[])
1042{
1043	enum nft_payload_bases base;
1044	unsigned int offset, len;
1045	int err;
1046
1047	if (tb[NFTA_PAYLOAD_BASE] == NULL ||
1048	    tb[NFTA_PAYLOAD_OFFSET] == NULL ||
1049	    tb[NFTA_PAYLOAD_LEN] == NULL)
1050		return ERR_PTR(-EINVAL);
1051
1052	base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
1053	switch (base) {
1054	case NFT_PAYLOAD_LL_HEADER:
1055	case NFT_PAYLOAD_NETWORK_HEADER:
1056	case NFT_PAYLOAD_TRANSPORT_HEADER:
1057	case NFT_PAYLOAD_INNER_HEADER:
1058		break;
1059	default:
1060		return ERR_PTR(-EOPNOTSUPP);
1061	}
1062
1063	if (tb[NFTA_PAYLOAD_SREG] != NULL) {
1064		if (tb[NFTA_PAYLOAD_DREG] != NULL)
1065			return ERR_PTR(-EINVAL);
1066		return &nft_payload_set_ops;
1067	}
1068
1069	if (tb[NFTA_PAYLOAD_DREG] == NULL)
1070		return ERR_PTR(-EINVAL);
1071
1072	err = nft_parse_u32_check(tb[NFTA_PAYLOAD_OFFSET], U8_MAX, &offset);
1073	if (err < 0)
1074		return ERR_PTR(err);
1075
1076	err = nft_parse_u32_check(tb[NFTA_PAYLOAD_LEN], U8_MAX, &len);
1077	if (err < 0)
1078		return ERR_PTR(err);
1079
1080	if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
1081	    base != NFT_PAYLOAD_LL_HEADER && base != NFT_PAYLOAD_INNER_HEADER)
1082		return &nft_payload_fast_ops;
1083	else
1084		return &nft_payload_ops;
1085}
1086
1087struct nft_expr_type nft_payload_type __read_mostly = {
1088	.name		= "payload",
1089	.select_ops	= nft_payload_select_ops,
1090	.inner_ops	= &nft_payload_inner_ops,
1091	.policy		= nft_payload_policy,
1092	.maxattr	= NFTA_PAYLOAD_MAX,
1093	.owner		= THIS_MODULE,
1094};