Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 *
5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
6 */
7
8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/module.h>
11#include <linux/netlink.h>
12#include <linux/netfilter.h>
13#include <linux/netfilter/nf_tables.h>
14#include <net/netfilter/nf_tables_core.h>
15#include <net/netfilter/nf_tables.h>
16#include <net/netfilter/nf_tables_offload.h>
17
18struct nft_bitwise {
19 u8 sreg;
20 u8 sreg2;
21 u8 dreg;
22 enum nft_bitwise_ops op:8;
23 u8 len;
24 struct nft_data mask;
25 struct nft_data xor;
26 struct nft_data data;
27};
28
29static void nft_bitwise_eval_mask_xor(u32 *dst, const u32 *src,
30 const struct nft_bitwise *priv)
31{
32 unsigned int i;
33
34 for (i = 0; i < DIV_ROUND_UP(priv->len, sizeof(u32)); i++)
35 dst[i] = (src[i] & priv->mask.data[i]) ^ priv->xor.data[i];
36}
37
38static void nft_bitwise_eval_lshift(u32 *dst, const u32 *src,
39 const struct nft_bitwise *priv)
40{
41 u32 shift = priv->data.data[0];
42 unsigned int i;
43 u32 carry = 0;
44
45 for (i = DIV_ROUND_UP(priv->len, sizeof(u32)); i > 0; i--) {
46 dst[i - 1] = (src[i - 1] << shift) | carry;
47 carry = src[i - 1] >> (BITS_PER_TYPE(u32) - shift);
48 }
49}
50
51static void nft_bitwise_eval_rshift(u32 *dst, const u32 *src,
52 const struct nft_bitwise *priv)
53{
54 u32 shift = priv->data.data[0];
55 unsigned int i;
56 u32 carry = 0;
57
58 for (i = 0; i < DIV_ROUND_UP(priv->len, sizeof(u32)); i++) {
59 dst[i] = carry | (src[i] >> shift);
60 carry = src[i] << (BITS_PER_TYPE(u32) - shift);
61 }
62}
63
64static void nft_bitwise_eval_and(u32 *dst, const u32 *src, const u32 *src2,
65 const struct nft_bitwise *priv)
66{
67 unsigned int i, n;
68
69 for (i = 0, n = DIV_ROUND_UP(priv->len, sizeof(u32)); i < n; i++)
70 dst[i] = src[i] & src2[i];
71}
72
73static void nft_bitwise_eval_or(u32 *dst, const u32 *src, const u32 *src2,
74 const struct nft_bitwise *priv)
75{
76 unsigned int i, n;
77
78 for (i = 0, n = DIV_ROUND_UP(priv->len, sizeof(u32)); i < n; i++)
79 dst[i] = src[i] | src2[i];
80}
81
82static void nft_bitwise_eval_xor(u32 *dst, const u32 *src, const u32 *src2,
83 const struct nft_bitwise *priv)
84{
85 unsigned int i, n;
86
87 for (i = 0, n = DIV_ROUND_UP(priv->len, sizeof(u32)); i < n; i++)
88 dst[i] = src[i] ^ src2[i];
89}
90
91void nft_bitwise_eval(const struct nft_expr *expr,
92 struct nft_regs *regs, const struct nft_pktinfo *pkt)
93{
94 const struct nft_bitwise *priv = nft_expr_priv(expr);
95 const u32 *src = ®s->data[priv->sreg], *src2;
96 u32 *dst = ®s->data[priv->dreg];
97
98 if (priv->op == NFT_BITWISE_MASK_XOR) {
99 nft_bitwise_eval_mask_xor(dst, src, priv);
100 return;
101 }
102 if (priv->op == NFT_BITWISE_LSHIFT) {
103 nft_bitwise_eval_lshift(dst, src, priv);
104 return;
105 }
106 if (priv->op == NFT_BITWISE_RSHIFT) {
107 nft_bitwise_eval_rshift(dst, src, priv);
108 return;
109 }
110
111 src2 = priv->sreg2 ? ®s->data[priv->sreg2] : priv->data.data;
112
113 if (priv->op == NFT_BITWISE_AND) {
114 nft_bitwise_eval_and(dst, src, src2, priv);
115 return;
116 }
117 if (priv->op == NFT_BITWISE_OR) {
118 nft_bitwise_eval_or(dst, src, src2, priv);
119 return;
120 }
121 if (priv->op == NFT_BITWISE_XOR) {
122 nft_bitwise_eval_xor(dst, src, src2, priv);
123 return;
124 }
125}
126
127static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
128 [NFTA_BITWISE_SREG] = NLA_POLICY_MAX(NLA_BE32, NFT_REG32_MAX),
129 [NFTA_BITWISE_SREG2] = NLA_POLICY_MAX(NLA_BE32, NFT_REG32_MAX),
130 [NFTA_BITWISE_DREG] = NLA_POLICY_MAX(NLA_BE32, NFT_REG32_MAX),
131 [NFTA_BITWISE_LEN] = { .type = NLA_U32 },
132 [NFTA_BITWISE_MASK] = { .type = NLA_NESTED },
133 [NFTA_BITWISE_XOR] = { .type = NLA_NESTED },
134 [NFTA_BITWISE_OP] = NLA_POLICY_MAX(NLA_BE32, 255),
135 [NFTA_BITWISE_DATA] = { .type = NLA_NESTED },
136};
137
138static int nft_bitwise_init_mask_xor(struct nft_bitwise *priv,
139 const struct nlattr *const tb[])
140{
141 struct nft_data_desc mask = {
142 .type = NFT_DATA_VALUE,
143 .size = sizeof(priv->mask),
144 .len = priv->len,
145 };
146 struct nft_data_desc xor = {
147 .type = NFT_DATA_VALUE,
148 .size = sizeof(priv->xor),
149 .len = priv->len,
150 };
151 int err;
152
153 if (tb[NFTA_BITWISE_DATA] ||
154 tb[NFTA_BITWISE_SREG2])
155 return -EINVAL;
156
157 if (!tb[NFTA_BITWISE_MASK] ||
158 !tb[NFTA_BITWISE_XOR])
159 return -EINVAL;
160
161 err = nft_data_init(NULL, &priv->mask, &mask, tb[NFTA_BITWISE_MASK]);
162 if (err < 0)
163 return err;
164
165 err = nft_data_init(NULL, &priv->xor, &xor, tb[NFTA_BITWISE_XOR]);
166 if (err < 0)
167 goto err_xor_err;
168
169 return 0;
170
171err_xor_err:
172 nft_data_release(&priv->mask, mask.type);
173
174 return err;
175}
176
177static int nft_bitwise_init_shift(struct nft_bitwise *priv,
178 const struct nlattr *const tb[])
179{
180 struct nft_data_desc desc = {
181 .type = NFT_DATA_VALUE,
182 .size = sizeof(priv->data),
183 .len = sizeof(u32),
184 };
185 int err;
186
187 if (tb[NFTA_BITWISE_MASK] ||
188 tb[NFTA_BITWISE_XOR] ||
189 tb[NFTA_BITWISE_SREG2])
190 return -EINVAL;
191
192 if (!tb[NFTA_BITWISE_DATA])
193 return -EINVAL;
194
195 err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_BITWISE_DATA]);
196 if (err < 0)
197 return err;
198
199 if (priv->data.data[0] >= BITS_PER_TYPE(u32)) {
200 nft_data_release(&priv->data, desc.type);
201 return -EINVAL;
202 }
203
204 return 0;
205}
206
207static int nft_bitwise_init_bool(const struct nft_ctx *ctx,
208 struct nft_bitwise *priv,
209 const struct nlattr *const tb[])
210{
211 int err;
212
213 if (tb[NFTA_BITWISE_MASK] ||
214 tb[NFTA_BITWISE_XOR])
215 return -EINVAL;
216
217 if ((!tb[NFTA_BITWISE_DATA] && !tb[NFTA_BITWISE_SREG2]) ||
218 (tb[NFTA_BITWISE_DATA] && tb[NFTA_BITWISE_SREG2]))
219 return -EINVAL;
220
221 if (tb[NFTA_BITWISE_DATA]) {
222 struct nft_data_desc desc = {
223 .type = NFT_DATA_VALUE,
224 .size = sizeof(priv->data),
225 .len = priv->len,
226 };
227
228 err = nft_data_init(NULL, &priv->data, &desc,
229 tb[NFTA_BITWISE_DATA]);
230 if (err < 0)
231 return err;
232 } else {
233 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG2],
234 &priv->sreg2, priv->len);
235 if (err < 0)
236 return err;
237 }
238
239 return 0;
240}
241
242static int nft_bitwise_init(const struct nft_ctx *ctx,
243 const struct nft_expr *expr,
244 const struct nlattr * const tb[])
245{
246 struct nft_bitwise *priv = nft_expr_priv(expr);
247 u32 len;
248 int err;
249
250 err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
251 if (err < 0)
252 return err;
253
254 priv->len = len;
255
256 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG], &priv->sreg,
257 priv->len);
258 if (err < 0)
259 return err;
260
261 err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG],
262 &priv->dreg, NULL, NFT_DATA_VALUE,
263 priv->len);
264 if (err < 0)
265 return err;
266
267 if (tb[NFTA_BITWISE_OP]) {
268 priv->op = ntohl(nla_get_be32(tb[NFTA_BITWISE_OP]));
269 switch (priv->op) {
270 case NFT_BITWISE_MASK_XOR:
271 case NFT_BITWISE_LSHIFT:
272 case NFT_BITWISE_RSHIFT:
273 case NFT_BITWISE_AND:
274 case NFT_BITWISE_OR:
275 case NFT_BITWISE_XOR:
276 break;
277 default:
278 return -EOPNOTSUPP;
279 }
280 } else {
281 priv->op = NFT_BITWISE_MASK_XOR;
282 }
283
284 switch(priv->op) {
285 case NFT_BITWISE_MASK_XOR:
286 err = nft_bitwise_init_mask_xor(priv, tb);
287 break;
288 case NFT_BITWISE_LSHIFT:
289 case NFT_BITWISE_RSHIFT:
290 err = nft_bitwise_init_shift(priv, tb);
291 break;
292 case NFT_BITWISE_AND:
293 case NFT_BITWISE_OR:
294 case NFT_BITWISE_XOR:
295 err = nft_bitwise_init_bool(ctx, priv, tb);
296 break;
297 }
298
299 return err;
300}
301
302static int nft_bitwise_dump_mask_xor(struct sk_buff *skb,
303 const struct nft_bitwise *priv)
304{
305 if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
306 NFT_DATA_VALUE, priv->len) < 0)
307 return -1;
308
309 if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
310 NFT_DATA_VALUE, priv->len) < 0)
311 return -1;
312
313 return 0;
314}
315
316static int nft_bitwise_dump_shift(struct sk_buff *skb,
317 const struct nft_bitwise *priv)
318{
319 if (nft_data_dump(skb, NFTA_BITWISE_DATA, &priv->data,
320 NFT_DATA_VALUE, sizeof(u32)) < 0)
321 return -1;
322 return 0;
323}
324
325static int nft_bitwise_dump_bool(struct sk_buff *skb,
326 const struct nft_bitwise *priv)
327{
328 if (priv->sreg2) {
329 if (nft_dump_register(skb, NFTA_BITWISE_SREG2, priv->sreg2))
330 return -1;
331 } else {
332 if (nft_data_dump(skb, NFTA_BITWISE_DATA, &priv->data,
333 NFT_DATA_VALUE, sizeof(u32)) < 0)
334 return -1;
335 }
336
337 return 0;
338}
339
340static int nft_bitwise_dump(struct sk_buff *skb,
341 const struct nft_expr *expr, bool reset)
342{
343 const struct nft_bitwise *priv = nft_expr_priv(expr);
344 int err = 0;
345
346 if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
347 return -1;
348 if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
349 return -1;
350 if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
351 return -1;
352 if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(priv->op)))
353 return -1;
354
355 switch (priv->op) {
356 case NFT_BITWISE_MASK_XOR:
357 err = nft_bitwise_dump_mask_xor(skb, priv);
358 break;
359 case NFT_BITWISE_LSHIFT:
360 case NFT_BITWISE_RSHIFT:
361 err = nft_bitwise_dump_shift(skb, priv);
362 break;
363 case NFT_BITWISE_AND:
364 case NFT_BITWISE_OR:
365 case NFT_BITWISE_XOR:
366 err = nft_bitwise_dump_bool(skb, priv);
367 break;
368 }
369
370 return err;
371}
372
373static struct nft_data zero;
374
375static int nft_bitwise_offload(struct nft_offload_ctx *ctx,
376 struct nft_flow_rule *flow,
377 const struct nft_expr *expr)
378{
379 const struct nft_bitwise *priv = nft_expr_priv(expr);
380 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
381
382 if (priv->op != NFT_BITWISE_MASK_XOR)
383 return -EOPNOTSUPP;
384
385 if (memcmp(&priv->xor, &zero, sizeof(priv->xor)) ||
386 priv->sreg != priv->dreg || priv->len != reg->len)
387 return -EOPNOTSUPP;
388
389 memcpy(®->mask, &priv->mask, sizeof(priv->mask));
390
391 return 0;
392}
393
394static const struct nft_expr_ops nft_bitwise_ops = {
395 .type = &nft_bitwise_type,
396 .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
397 .eval = nft_bitwise_eval,
398 .init = nft_bitwise_init,
399 .dump = nft_bitwise_dump,
400 .offload = nft_bitwise_offload,
401};
402
403static int
404nft_bitwise_extract_u32_data(const struct nlattr * const tb, u32 *out)
405{
406 struct nft_data data;
407 struct nft_data_desc desc = {
408 .type = NFT_DATA_VALUE,
409 .size = sizeof(data),
410 .len = sizeof(u32),
411 };
412 int err;
413
414 err = nft_data_init(NULL, &data, &desc, tb);
415 if (err < 0)
416 return err;
417
418 *out = data.data[0];
419
420 return 0;
421}
422
423static int nft_bitwise_fast_init(const struct nft_ctx *ctx,
424 const struct nft_expr *expr,
425 const struct nlattr * const tb[])
426{
427 struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
428 int err;
429
430 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG], &priv->sreg,
431 sizeof(u32));
432 if (err < 0)
433 return err;
434
435 err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG], &priv->dreg,
436 NULL, NFT_DATA_VALUE, sizeof(u32));
437 if (err < 0)
438 return err;
439
440 if (tb[NFTA_BITWISE_DATA] ||
441 tb[NFTA_BITWISE_SREG2])
442 return -EINVAL;
443
444 if (!tb[NFTA_BITWISE_MASK] ||
445 !tb[NFTA_BITWISE_XOR])
446 return -EINVAL;
447
448 err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_MASK], &priv->mask);
449 if (err < 0)
450 return err;
451
452 err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_XOR], &priv->xor);
453 if (err < 0)
454 return err;
455
456 return 0;
457}
458
459static int
460nft_bitwise_fast_dump(struct sk_buff *skb,
461 const struct nft_expr *expr, bool reset)
462{
463 const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
464 struct nft_data data;
465
466 if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
467 return -1;
468 if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
469 return -1;
470 if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(sizeof(u32))))
471 return -1;
472 if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(NFT_BITWISE_MASK_XOR)))
473 return -1;
474
475 data.data[0] = priv->mask;
476 if (nft_data_dump(skb, NFTA_BITWISE_MASK, &data,
477 NFT_DATA_VALUE, sizeof(u32)) < 0)
478 return -1;
479
480 data.data[0] = priv->xor;
481 if (nft_data_dump(skb, NFTA_BITWISE_XOR, &data,
482 NFT_DATA_VALUE, sizeof(u32)) < 0)
483 return -1;
484
485 return 0;
486}
487
488static int nft_bitwise_fast_offload(struct nft_offload_ctx *ctx,
489 struct nft_flow_rule *flow,
490 const struct nft_expr *expr)
491{
492 const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
493 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
494
495 if (priv->xor || priv->sreg != priv->dreg || reg->len != sizeof(u32))
496 return -EOPNOTSUPP;
497
498 reg->mask.data[0] = priv->mask;
499 return 0;
500}
501
502const struct nft_expr_ops nft_bitwise_fast_ops = {
503 .type = &nft_bitwise_type,
504 .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise_fast_expr)),
505 .eval = NULL, /* inlined */
506 .init = nft_bitwise_fast_init,
507 .dump = nft_bitwise_fast_dump,
508 .offload = nft_bitwise_fast_offload,
509};
510
511static const struct nft_expr_ops *
512nft_bitwise_select_ops(const struct nft_ctx *ctx,
513 const struct nlattr * const tb[])
514{
515 int err;
516 u32 len;
517
518 if (!tb[NFTA_BITWISE_LEN] ||
519 !tb[NFTA_BITWISE_SREG] ||
520 !tb[NFTA_BITWISE_DREG])
521 return ERR_PTR(-EINVAL);
522
523 err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
524 if (err < 0)
525 return ERR_PTR(err);
526
527 if (len != sizeof(u32))
528 return &nft_bitwise_ops;
529
530 if (tb[NFTA_BITWISE_OP] &&
531 ntohl(nla_get_be32(tb[NFTA_BITWISE_OP])) != NFT_BITWISE_MASK_XOR)
532 return &nft_bitwise_ops;
533
534 return &nft_bitwise_fast_ops;
535}
536
537struct nft_expr_type nft_bitwise_type __read_mostly = {
538 .name = "bitwise",
539 .select_ops = nft_bitwise_select_ops,
540 .policy = nft_bitwise_policy,
541 .maxattr = NFTA_BITWISE_MAX,
542 .owner = THIS_MODULE,
543};