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UBUNTU: Ubuntu-5.15.0-39.42
[mirror_ubuntu-jammy-kernel.git] / net / netfilter / nft_payload.c
CommitLineData
d2912cb1 1// SPDX-License-Identifier: GPL-2.0-only
96518518 2/*
ef1f7df9 3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
18140969 4 * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
96518518 5 *
96518518
PM		 6 * Development of this code funded by Astaro AG (http://www.astaro.com/)
7 */
8
9#include <linux/kernel.h>
8cfd23e6 10#include <linux/if_vlan.h>
96518518
PM		 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>
c9626a2c 18#include <net/netfilter/nf_tables_offload.h>
18140969
PNA		 19/* For layer 4 checksum field offset. */
20#include <linux/tcp.h>
21#include <linux/udp.h>
22#include <linux/icmpv6.h>
c9626a2c
PNA		 23#include <linux/ip.h>
24#include <linux/ipv6.h>
346e320c 25#include <net/sctp/checksum.h>
96518518 26
8dfd8b09
PNA		 27static bool nft_payload_rebuild_vlan_hdr(const struct sk_buff *skb, int mac_off,
28 struct vlan_ethhdr *veth)
29{
30 if (skb_copy_bits(skb, mac_off, veth, ETH_HLEN))
31 return false;
32
33 veth->h_vlan_proto = skb->vlan_proto;
34 veth->h_vlan_TCI = htons(skb_vlan_tag_get(skb));
35 veth->h_vlan_encapsulated_proto = skb->protocol;
36
37 return true;
38}
39
8cfd23e6
FW		 40/* add vlan header into the user buffer for if tag was removed by offloads */
41static bool
42nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
43{
44 int mac_off = skb_mac_header(skb) - skb->data;
f41f72d0 45 u8 *vlanh, *dst_u8 = (u8 *) d;
8cfd23e6 46 struct vlan_ethhdr veth;
f6ae9f12
PNA		 47 u8 vlan_hlen = 0;
48
49 if ((skb->protocol == htons(ETH_P_8021AD) ||
50 skb->protocol == htons(ETH_P_8021Q)) &&
51 offset >= VLAN_ETH_HLEN && offset < VLAN_ETH_HLEN + VLAN_HLEN)
52 vlan_hlen += VLAN_HLEN;
8cfd23e6
FW		 53
54 vlanh = (u8 *) &veth;
f6ae9f12 55 if (offset < VLAN_ETH_HLEN + vlan_hlen) {
f41f72d0 56 u8 ethlen = len;
8cfd23e6 57
f6ae9f12
PNA		 58 if (vlan_hlen &&
59 skb_copy_bits(skb, mac_off, &veth, VLAN_ETH_HLEN) < 0)
60 return false;
61 else if (!nft_payload_rebuild_vlan_hdr(skb, mac_off, &veth))
8cfd23e6
FW		 62 return false;
63
f6ae9f12
PNA		 64 if (offset + len > VLAN_ETH_HLEN + vlan_hlen)
65 ethlen -= offset + len - VLAN_ETH_HLEN + vlan_hlen;
8cfd23e6 66
f6ae9f12 67 memcpy(dst_u8, vlanh + offset - vlan_hlen, ethlen);
8cfd23e6
FW		 68
69 len -= ethlen;
70 if (len == 0)
71 return true;
72
73 dst_u8 += ethlen;
f6ae9f12 74 offset = ETH_HLEN + vlan_hlen;
f41f72d0 75 } else {
f6ae9f12 76 offset -= VLAN_HLEN + vlan_hlen;
8cfd23e6
FW		 77 }
78
8cfd23e6
FW		 79 return skb_copy_bits(skb, offset + mac_off, dst_u8, len) == 0;
80}
81
10870dd8
FW		 82void nft_payload_eval(const struct nft_expr *expr,
83 struct nft_regs *regs,
84 const struct nft_pktinfo *pkt)
96518518
PM		 85{
86 const struct nft_payload *priv = nft_expr_priv(expr);
87 const struct sk_buff *skb = pkt->skb;
49499c3e 88 u32 *dest = &regs->data[priv->dreg];
96518518
PM		 89 int offset;
90
1e105e6a
FW		 91 if (priv->len % NFT_REG32_SIZE)
92 dest[priv->len / NFT_REG32_SIZE] = 0;
93
96518518
PM		 94 switch (priv->base) {
95 case NFT_PAYLOAD_LL_HEADER:
96 if (!skb_mac_header_was_set(skb))
97 goto err;
8cfd23e6
FW		 98
99 if (skb_vlan_tag_present(skb)) {
100 if (!nft_payload_copy_vlan(dest, skb,
101 priv->offset, priv->len))
102 goto err;
103 return;
104 }
96518518
PM		 105 offset = skb_mac_header(skb) - skb->data;
106 break;
107 case NFT_PAYLOAD_NETWORK_HEADER:
108 offset = skb_network_offset(skb);
109 break;
110 case NFT_PAYLOAD_TRANSPORT_HEADER:
a20877b5
LZ		 111 if (!pkt->tprot_set)
112 goto err;
2d7b4ace 113 offset = nft_thoff(pkt);
96518518
PM		 114 break;
115 default:
116 BUG();
117 }
118 offset += priv->offset;
119
fad136ea 120 if (skb_copy_bits(skb, offset, dest, priv->len) < 0)
96518518
PM		 121 goto err;
122 return;
123err:
a55e22e9 124 regs->verdict.code = NFT_BREAK;
96518518
PM		 125}
126
127static const struct nla_policy nft_payload_policy[NFTA_PAYLOAD_MAX + 1] = {
7ec3f7b4
PM		 128 [NFTA_PAYLOAD_SREG] = { .type = NLA_U32 },
129 [NFTA_PAYLOAD_DREG] = { .type = NLA_U32 },
130 [NFTA_PAYLOAD_BASE] = { .type = NLA_U32 },
131 [NFTA_PAYLOAD_OFFSET] = { .type = NLA_U32 },
132 [NFTA_PAYLOAD_LEN] = { .type = NLA_U32 },
133 [NFTA_PAYLOAD_CSUM_TYPE] = { .type = NLA_U32 },
134 [NFTA_PAYLOAD_CSUM_OFFSET] = { .type = NLA_U32 },
9d6effb2 135 [NFTA_PAYLOAD_CSUM_FLAGS] = { .type = NLA_U32 },
96518518
PM		 136};
137
138static int nft_payload_init(const struct nft_ctx *ctx,
139 const struct nft_expr *expr,
140 const struct nlattr * const tb[])
141{
142 struct nft_payload *priv = nft_expr_priv(expr);
96518518 143
c29b72e0 144 priv->base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
96518518
PM		 145 priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
146 priv->len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
96518518 147
345023b0
PNA		 148 return nft_parse_register_store(ctx, tb[NFTA_PAYLOAD_DREG],
149 &priv->dreg, NULL, NFT_DATA_VALUE,
150 priv->len);
96518518
PM		 151}
152
153static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
154{
155 const struct nft_payload *priv = nft_expr_priv(expr);
156
b1c96ed3 157 if (nft_dump_register(skb, NFTA_PAYLOAD_DREG, priv->dreg) ||
96518518
PM		 158 nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
159 nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
160 nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)))
161 goto nla_put_failure;
162 return 0;
163
164nla_put_failure:
165 return -1;
166}
167
a5d45bc0
PNA		 168static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
169 u32 priv_len, u32 field_len)
170{
171 unsigned int remainder, delta, k;
172 struct nft_data mask = {};
173 __be32 remainder_mask;
174
175 if (priv_len == field_len) {
176 memset(&reg->mask, 0xff, priv_len);
177 return true;
178 } else if (priv_len > field_len) {
179 return false;
180 }
181
182 memset(&mask, 0xff, field_len);
183 remainder = priv_len % sizeof(u32);
184 if (remainder) {
185 k = priv_len / sizeof(u32);
186 delta = field_len - priv_len;
187 remainder_mask = htonl(~((1 << (delta * BITS_PER_BYTE)) - 1));
188 mask.data[k] = (__force u32)remainder_mask;
189 }
190
191 memcpy(&reg->mask, &mask, field_len);
192
193 return true;
194}
195
c9626a2c
PNA		 196static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
197 struct nft_flow_rule *flow,
198 const struct nft_payload *priv)
199{
200 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
201
202 switch (priv->offset) {
203 case offsetof(struct ethhdr, h_source):
a5d45bc0 204 if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
a69a85da 205 return -EOPNOTSUPP;
206
c9626a2c
PNA		 207 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
208 src, ETH_ALEN, reg);
209 break;
210 case offsetof(struct ethhdr, h_dest):
a5d45bc0 211 if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
a69a85da 212 return -EOPNOTSUPP;
213
c9626a2c
PNA		 214 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
215 dst, ETH_ALEN, reg);
216 break;
a82055af 217 case offsetof(struct ethhdr, h_proto):
a5d45bc0 218 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a82055af
PNA		 219 return -EOPNOTSUPP;
220
221 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic,
222 n_proto, sizeof(__be16), reg);
223 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
224 break;
225 case offsetof(struct vlan_ethhdr, h_vlan_TCI):
a5d45bc0 226 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a82055af
PNA		 227 return -EOPNOTSUPP;
228
ff4d90a8
PNA		 229 NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_VLAN, vlan,
230 vlan_tci, sizeof(__be16), reg,
231 NFT_OFFLOAD_F_NETWORK2HOST);
a82055af
PNA		 232 break;
233 case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
a5d45bc0 234 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a82055af
PNA		 235 return -EOPNOTSUPP;
236
237 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
238 vlan_tpid, sizeof(__be16), reg);
89d8fd44
PNA		 239 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
240 break;
241 case offsetof(struct vlan_ethhdr, h_vlan_TCI) + sizeof(struct vlan_hdr):
a5d45bc0 242 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
89d8fd44
PNA		 243 return -EOPNOTSUPP;
244
ff4d90a8
PNA		 245 NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
246 vlan_tci, sizeof(__be16), reg,
247 NFT_OFFLOAD_F_NETWORK2HOST);
89d8fd44
PNA		 248 break;
249 case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
250 sizeof(struct vlan_hdr):
a5d45bc0 251 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
89d8fd44
PNA		 252 return -EOPNOTSUPP;
253
14c20643 254 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
89d8fd44 255 vlan_tpid, sizeof(__be16), reg);
14c20643 256 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
a82055af 257 break;
a69a85da 258 default:
259 return -EOPNOTSUPP;
c9626a2c
PNA		 260 }
261
262 return 0;
263}
264
265static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
266 struct nft_flow_rule *flow,
267 const struct nft_payload *priv)
268{
269 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
270
271 switch (priv->offset) {
272 case offsetof(struct iphdr, saddr):
a5d45bc0
PNA		 273 if (!nft_payload_offload_mask(reg, priv->len,
274 sizeof(struct in_addr)))
a69a85da 275 return -EOPNOTSUPP;
276
c9626a2c
PNA		 277 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
278 sizeof(struct in_addr), reg);
3c78e9e0 279 nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
c9626a2c
PNA		 280 break;
281 case offsetof(struct iphdr, daddr):
a5d45bc0
PNA		 282 if (!nft_payload_offload_mask(reg, priv->len,
283 sizeof(struct in_addr)))
a69a85da 284 return -EOPNOTSUPP;
285
c9626a2c
PNA		 286 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
287 sizeof(struct in_addr), reg);
3c78e9e0 288 nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
c9626a2c
PNA		 289 break;
290 case offsetof(struct iphdr, protocol):
a5d45bc0 291 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
a69a85da 292 return -EOPNOTSUPP;
293
c9626a2c
PNA		 294 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
295 sizeof(__u8), reg);
296 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
297 break;
298 default:
299 return -EOPNOTSUPP;
300 }
301
302 return 0;
303}
304
305static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
306 struct nft_flow_rule *flow,
307 const struct nft_payload *priv)
308{
309 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
310
311 switch (priv->offset) {
312 case offsetof(struct ipv6hdr, saddr):
a5d45bc0
PNA		 313 if (!nft_payload_offload_mask(reg, priv->len,
314 sizeof(struct in6_addr)))
a69a85da 315 return -EOPNOTSUPP;
316
c9626a2c
PNA		 317 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
318 sizeof(struct in6_addr), reg);
3c78e9e0 319 nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
c9626a2c
PNA		 320 break;
321 case offsetof(struct ipv6hdr, daddr):
a5d45bc0
PNA		 322 if (!nft_payload_offload_mask(reg, priv->len,
323 sizeof(struct in6_addr)))
a69a85da 324 return -EOPNOTSUPP;
325
c9626a2c
PNA		 326 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
327 sizeof(struct in6_addr), reg);
3c78e9e0 328 nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
c9626a2c
PNA		 329 break;
330 case offsetof(struct ipv6hdr, nexthdr):
a5d45bc0 331 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
a69a85da 332 return -EOPNOTSUPP;
333
c9626a2c
PNA		 334 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
335 sizeof(__u8), reg);
336 nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
337 break;
338 default:
339 return -EOPNOTSUPP;
340 }
341
342 return 0;
343}
344
345static int nft_payload_offload_nh(struct nft_offload_ctx *ctx,
346 struct nft_flow_rule *flow,
347 const struct nft_payload *priv)
348{
349 int err;
350
351 switch (ctx->dep.l3num) {
352 case htons(ETH_P_IP):
353 err = nft_payload_offload_ip(ctx, flow, priv);
354 break;
355 case htons(ETH_P_IPV6):
356 err = nft_payload_offload_ip6(ctx, flow, priv);
357 break;
358 default:
359 return -EOPNOTSUPP;
360 }
361
362 return err;
363}
364
365static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx,
366 struct nft_flow_rule *flow,
367 const struct nft_payload *priv)
368{
369 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
370
371 switch (priv->offset) {
372 case offsetof(struct tcphdr, source):
a5d45bc0 373 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a69a85da 374 return -EOPNOTSUPP;
375
c9626a2c
PNA		 376 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
377 sizeof(__be16), reg);
378 break;
379 case offsetof(struct tcphdr, dest):
a5d45bc0 380 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a69a85da 381 return -EOPNOTSUPP;
382
c9626a2c
PNA		 383 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
384 sizeof(__be16), reg);
385 break;
386 default:
387 return -EOPNOTSUPP;
388 }
389
390 return 0;
391}
392
393static int nft_payload_offload_udp(struct nft_offload_ctx *ctx,
394 struct nft_flow_rule *flow,
395 const struct nft_payload *priv)
396{
397 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
398
399 switch (priv->offset) {
400 case offsetof(struct udphdr, source):
a5d45bc0 401 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a69a85da 402 return -EOPNOTSUPP;
403
c9626a2c
PNA		 404 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
405 sizeof(__be16), reg);
406 break;
407 case offsetof(struct udphdr, dest):
a5d45bc0 408 if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
a69a85da 409 return -EOPNOTSUPP;
410
c9626a2c
PNA		 411 NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
412 sizeof(__be16), reg);
413 break;
414 default:
415 return -EOPNOTSUPP;
416 }
417
418 return 0;
419}
420
421static int nft_payload_offload_th(struct nft_offload_ctx *ctx,
422 struct nft_flow_rule *flow,
423 const struct nft_payload *priv)
424{
425 int err;
426
427 switch (ctx->dep.protonum) {
428 case IPPROTO_TCP:
429 err = nft_payload_offload_tcp(ctx, flow, priv);
430 break;
431 case IPPROTO_UDP:
432 err = nft_payload_offload_udp(ctx, flow, priv);
433 break;
434 default:
435 return -EOPNOTSUPP;
436 }
437
438 return err;
439}
440
441static int nft_payload_offload(struct nft_offload_ctx *ctx,
442 struct nft_flow_rule *flow,
443 const struct nft_expr *expr)
444{
445 const struct nft_payload *priv = nft_expr_priv(expr);
446 int err;
447
448 switch (priv->base) {
449 case NFT_PAYLOAD_LL_HEADER:
450 err = nft_payload_offload_ll(ctx, flow, priv);
451 break;
452 case NFT_PAYLOAD_NETWORK_HEADER:
453 err = nft_payload_offload_nh(ctx, flow, priv);
454 break;
455 case NFT_PAYLOAD_TRANSPORT_HEADER:
456 err = nft_payload_offload_th(ctx, flow, priv);
457 break;
458 default:
459 err = -EOPNOTSUPP;
460 break;
461 }
462 return err;
463}
464
ef1f7df9
PM		 465static const struct nft_expr_ops nft_payload_ops = {
466 .type = &nft_payload_type,
96518518 467 .size = NFT_EXPR_SIZE(sizeof(struct nft_payload)),
96518518
PM		 468 .eval = nft_payload_eval,
469 .init = nft_payload_init,
470 .dump = nft_payload_dump,
c9626a2c 471 .offload = nft_payload_offload,
ef1f7df9
PM		 472};
473
c29b72e0
PM		 474const struct nft_expr_ops nft_payload_fast_ops = {
475 .type = &nft_payload_type,
476 .size = NFT_EXPR_SIZE(sizeof(struct nft_payload)),
477 .eval = nft_payload_eval,
478 .init = nft_payload_init,
479 .dump = nft_payload_dump,
c9626a2c 480 .offload = nft_payload_offload,
c29b72e0
PM		 481};
482
18140969
PNA		 483static inline void nft_csum_replace(__sum16 *sum, __wsum fsum, __wsum tsum)
484{
485 *sum = csum_fold(csum_add(csum_sub(~csum_unfold(*sum), fsum), tsum));
486 if (*sum == 0)
487 *sum = CSUM_MANGLED_0;
488}
489
490static bool nft_payload_udp_checksum(struct sk_buff *skb, unsigned int thoff)
491{
492 struct udphdr *uh, _uh;
493
494 uh = skb_header_pointer(skb, thoff, sizeof(_uh), &_uh);
495 if (!uh)
496 return false;
497
5fd02ebe 498 return (__force bool)uh->check;
18140969
PNA		 499}
500
501static int nft_payload_l4csum_offset(const struct nft_pktinfo *pkt,
502 struct sk_buff *skb,
503 unsigned int *l4csum_offset)
504{
20044428
PNA		 505 if (pkt->fragoff)
506 return -1;
507
18140969
PNA		 508 switch (pkt->tprot) {
509 case IPPROTO_TCP:
510 *l4csum_offset = offsetof(struct tcphdr, check);
511 break;
512 case IPPROTO_UDP:
2d7b4ace 513 if (!nft_payload_udp_checksum(skb, nft_thoff(pkt)))
18140969 514 return -1;
954d8297 515 fallthrough;
18140969
PNA		 516 case IPPROTO_UDPLITE:
517 *l4csum_offset = offsetof(struct udphdr, check);
518 break;
519 case IPPROTO_ICMPV6:
520 *l4csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
521 break;
522 default:
523 return -1;
524 }
525
2d7b4ace 526 *l4csum_offset += nft_thoff(pkt);
18140969
PNA		 527 return 0;
528}
529
346e320c
DC		 530static int nft_payload_csum_sctp(struct sk_buff *skb, int offset)
531{
532 struct sctphdr *sh;
533
534 if (skb_ensure_writable(skb, offset + sizeof(*sh)))
535 return -1;
536
537 sh = (struct sctphdr *)(skb->data + offset);
538 sh->checksum = sctp_compute_cksum(skb, offset);
539 skb->ip_summed = CHECKSUM_UNNECESSARY;
540 return 0;
541}
542
18140969
PNA		 543static int nft_payload_l4csum_update(const struct nft_pktinfo *pkt,
544 struct sk_buff *skb,
545 __wsum fsum, __wsum tsum)
546{
547 int l4csum_offset;
548 __sum16 sum;
549
550 /* If we cannot determine layer 4 checksum offset or this packet doesn't
551 * require layer 4 checksum recalculation, skip this packet.
552 */
553 if (nft_payload_l4csum_offset(pkt, skb, &l4csum_offset) < 0)
554 return 0;
555
556 if (skb_copy_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
557 return -1;
558
559 /* Checksum mangling for an arbitrary amount of bytes, based on
560 * inet_proto_csum_replace*() functions.
561 */
562 if (skb->ip_summed != CHECKSUM_PARTIAL) {
563 nft_csum_replace(&sum, fsum, tsum);
564 if (skb->ip_summed == CHECKSUM_COMPLETE) {
565 skb->csum = ~csum_add(csum_sub(~(skb->csum), fsum),
566 tsum);
567 }
568 } else {
569 sum = ~csum_fold(csum_add(csum_sub(csum_unfold(sum), fsum),
570 tsum));
571 }
572
7418ee4c 573 if (skb_ensure_writable(skb, l4csum_offset + sizeof(sum)) ||
18140969
PNA		 574 skb_store_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
575 return -1;
576
577 return 0;
578}
579
053d20f5
PNA		 580static int nft_payload_csum_inet(struct sk_buff *skb, const u32 *src,
581 __wsum fsum, __wsum tsum, int csum_offset)
582{
583 __sum16 sum;
584
585 if (skb_copy_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
586 return -1;
587
588 nft_csum_replace(&sum, fsum, tsum);
7418ee4c 589 if (skb_ensure_writable(skb, csum_offset + sizeof(sum)) ||
053d20f5
PNA		 590 skb_store_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
591 return -1;
592
593 return 0;
594}
595
7ec3f7b4
PM		 596static void nft_payload_set_eval(const struct nft_expr *expr,
597 struct nft_regs *regs,
598 const struct nft_pktinfo *pkt)
599{
600 const struct nft_payload_set *priv = nft_expr_priv(expr);
601 struct sk_buff *skb = pkt->skb;
602 const u32 *src = &regs->data[priv->sreg];
603 int offset, csum_offset;
604 __wsum fsum, tsum;
7ec3f7b4
PM		 605
606 switch (priv->base) {
607 case NFT_PAYLOAD_LL_HEADER:
608 if (!skb_mac_header_was_set(skb))
609 goto err;
610 offset = skb_mac_header(skb) - skb->data;
611 break;
612 case NFT_PAYLOAD_NETWORK_HEADER:
613 offset = skb_network_offset(skb);
614 break;
615 case NFT_PAYLOAD_TRANSPORT_HEADER:
a20877b5
LZ		 616 if (!pkt->tprot_set)
617 goto err;
2d7b4ace 618 offset = nft_thoff(pkt);
7ec3f7b4
PM		 619 break;
620 default:
621 BUG();
622 }
623
624 csum_offset = offset + priv->csum_offset;
625 offset += priv->offset;
626
053d20f5 627 if ((priv->csum_type == NFT_PAYLOAD_CSUM_INET || priv->csum_flags) &&
7ec3f7b4
PM		 628 (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER ||
629 skb->ip_summed != CHECKSUM_PARTIAL)) {
7ec3f7b4
PM		 630 fsum = skb_checksum(skb, offset, priv->len, 0);
631 tsum = csum_partial(src, priv->len, 0);
7ec3f7b4 632
053d20f5
PNA		 633 if (priv->csum_type == NFT_PAYLOAD_CSUM_INET &&
634 nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))
7ec3f7b4 635 goto err;
18140969
PNA		 636
637 if (priv->csum_flags &&
638 nft_payload_l4csum_update(pkt, skb, fsum, tsum) < 0)
639 goto err;
7ec3f7b4
PM		 640 }
641
7418ee4c 642 if (skb_ensure_writable(skb, max(offset + priv->len, 0)) ||
7ec3f7b4
PM		 643 skb_store_bits(skb, offset, src, priv->len) < 0)
644 goto err;
645
346e320c
DC		 646 if (priv->csum_type == NFT_PAYLOAD_CSUM_SCTP &&
647 pkt->tprot == IPPROTO_SCTP &&
648 skb->ip_summed != CHECKSUM_PARTIAL) {
2d7b4ace 649 if (nft_payload_csum_sctp(skb, nft_thoff(pkt)))
346e320c
DC		 650 goto err;
651 }
652
7ec3f7b4
PM		 653 return;
654err:
655 regs->verdict.code = NFT_BREAK;
656}
657
658static int nft_payload_set_init(const struct nft_ctx *ctx,
659 const struct nft_expr *expr,
660 const struct nlattr * const tb[])
661{
662 struct nft_payload_set *priv = nft_expr_priv(expr);
663
664 priv->base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
665 priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
666 priv->len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
7ec3f7b4
PM		 667
668 if (tb[NFTA_PAYLOAD_CSUM_TYPE])
669 priv->csum_type =
670 ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_TYPE]));
671 if (tb[NFTA_PAYLOAD_CSUM_OFFSET])
672 priv->csum_offset =
673 ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_OFFSET]));
18140969
PNA		 674 if (tb[NFTA_PAYLOAD_CSUM_FLAGS]) {
675 u32 flags;
676
677 flags = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_FLAGS]));
678 if (flags & ~NFT_PAYLOAD_L4CSUM_PSEUDOHDR)
679 return -EINVAL;
680
681 priv->csum_flags = flags;
682 }
7ec3f7b4
PM		 683
684 switch (priv->csum_type) {
685 case NFT_PAYLOAD_CSUM_NONE:
686 case NFT_PAYLOAD_CSUM_INET:
687 break;
346e320c
DC		 688 case NFT_PAYLOAD_CSUM_SCTP:
689 if (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER)
690 return -EINVAL;
691
692 if (priv->csum_offset != offsetof(struct sctphdr, checksum))
693 return -EINVAL;
694 break;
7ec3f7b4
PM		 695 default:
696 return -EOPNOTSUPP;
697 }
698
4f16d25c
PNA		 699 return nft_parse_register_load(tb[NFTA_PAYLOAD_SREG], &priv->sreg,
700 priv->len);
7ec3f7b4
PM		 701}
702
703static int nft_payload_set_dump(struct sk_buff *skb, const struct nft_expr *expr)
704{
705 const struct nft_payload_set *priv = nft_expr_priv(expr);
706
707 if (nft_dump_register(skb, NFTA_PAYLOAD_SREG, priv->sreg) ||
708 nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
709 nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
710 nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)) ||
711 nla_put_be32(skb, NFTA_PAYLOAD_CSUM_TYPE, htonl(priv->csum_type)) ||
712 nla_put_be32(skb, NFTA_PAYLOAD_CSUM_OFFSET,
18140969
PNA		 713 htonl(priv->csum_offset)) ||
714 nla_put_be32(skb, NFTA_PAYLOAD_CSUM_FLAGS, htonl(priv->csum_flags)))
7ec3f7b4
PM		 715 goto nla_put_failure;
716 return 0;
717
718nla_put_failure:
719 return -1;
720}
721
722static const struct nft_expr_ops nft_payload_set_ops = {
723 .type = &nft_payload_type,
724 .size = NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),
725 .eval = nft_payload_set_eval,
726 .init = nft_payload_set_init,
727 .dump = nft_payload_set_dump,
728};
729
0ca743a5
PNA		 730static const struct nft_expr_ops *
731nft_payload_select_ops(const struct nft_ctx *ctx,
732 const struct nlattr * const tb[])
c29b72e0
PM		 733{
734 enum nft_payload_bases base;
735 unsigned int offset, len;
736
7ec3f7b4 737 if (tb[NFTA_PAYLOAD_BASE] == NULL ||
c29b72e0
PM		 738 tb[NFTA_PAYLOAD_OFFSET] == NULL ||
739 tb[NFTA_PAYLOAD_LEN] == NULL)
740 return ERR_PTR(-EINVAL);
741
742 base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
743 switch (base) {
744 case NFT_PAYLOAD_LL_HEADER:
745 case NFT_PAYLOAD_NETWORK_HEADER:
746 case NFT_PAYLOAD_TRANSPORT_HEADER:
747 break;
748 default:
749 return ERR_PTR(-EOPNOTSUPP);
750 }
751
7ec3f7b4
PM		 752 if (tb[NFTA_PAYLOAD_SREG] != NULL) {
753 if (tb[NFTA_PAYLOAD_DREG] != NULL)
754 return ERR_PTR(-EINVAL);
755 return &nft_payload_set_ops;
756 }
757
758 if (tb[NFTA_PAYLOAD_DREG] == NULL)
759 return ERR_PTR(-EINVAL);
760
c29b72e0 761 offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
45d9bcda 762 len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
c29b72e0 763
f627ed91
NA		 764 if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
765 base != NFT_PAYLOAD_LL_HEADER)
c29b72e0
PM		 766 return &nft_payload_fast_ops;
767 else
768 return &nft_payload_ops;
769}
770
4e24877e 771struct nft_expr_type nft_payload_type __read_mostly = {
ef1f7df9 772 .name = "payload",
c29b72e0 773 .select_ops = nft_payload_select_ops,
96518518
PM		 774 .policy = nft_payload_policy,
775 .maxattr = NFTA_PAYLOAD_MAX,
ef1f7df9 776 .owner = THIS_MODULE,
96518518 777};
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