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] ||
200 priv->data.data[0] >= BITS_PER_TYPE(u32)) {
201 nft_data_release(&priv->data, desc.type);
202 return -EINVAL;
203 }
204
205 return 0;
206}
207
208static int nft_bitwise_init_bool(const struct nft_ctx *ctx,
209 struct nft_bitwise *priv,
210 const struct nlattr *const tb[])
211{
212 int err;
213
214 if (tb[NFTA_BITWISE_MASK] ||
215 tb[NFTA_BITWISE_XOR])
216 return -EINVAL;
217
218 if ((!tb[NFTA_BITWISE_DATA] && !tb[NFTA_BITWISE_SREG2]) ||
219 (tb[NFTA_BITWISE_DATA] && tb[NFTA_BITWISE_SREG2]))
220 return -EINVAL;
221
222 if (tb[NFTA_BITWISE_DATA]) {
223 struct nft_data_desc desc = {
224 .type = NFT_DATA_VALUE,
225 .size = sizeof(priv->data),
226 .len = priv->len,
227 };
228
229 err = nft_data_init(NULL, &priv->data, &desc,
230 tb[NFTA_BITWISE_DATA]);
231 if (err < 0)
232 return err;
233 } else {
234 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG2],
235 &priv->sreg2, priv->len);
236 if (err < 0)
237 return err;
238 }
239
240 return 0;
241}
242
243static int nft_bitwise_init(const struct nft_ctx *ctx,
244 const struct nft_expr *expr,
245 const struct nlattr * const tb[])
246{
247 struct nft_bitwise *priv = nft_expr_priv(expr);
248 u32 len;
249 int err;
250
251 err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
252 if (err < 0)
253 return err;
254
255 priv->len = len;
256
257 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG], &priv->sreg,
258 priv->len);
259 if (err < 0)
260 return err;
261
262 err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG],
263 &priv->dreg, NULL, NFT_DATA_VALUE,
264 priv->len);
265 if (err < 0)
266 return err;
267
268 if (tb[NFTA_BITWISE_OP]) {
269 priv->op = ntohl(nla_get_be32(tb[NFTA_BITWISE_OP]));
270 switch (priv->op) {
271 case NFT_BITWISE_MASK_XOR:
272 case NFT_BITWISE_LSHIFT:
273 case NFT_BITWISE_RSHIFT:
274 case NFT_BITWISE_AND:
275 case NFT_BITWISE_OR:
276 case NFT_BITWISE_XOR:
277 break;
278 default:
279 return -EOPNOTSUPP;
280 }
281 } else {
282 priv->op = NFT_BITWISE_MASK_XOR;
283 }
284
285 switch(priv->op) {
286 case NFT_BITWISE_MASK_XOR:
287 err = nft_bitwise_init_mask_xor(priv, tb);
288 break;
289 case NFT_BITWISE_LSHIFT:
290 case NFT_BITWISE_RSHIFT:
291 err = nft_bitwise_init_shift(priv, tb);
292 break;
293 case NFT_BITWISE_AND:
294 case NFT_BITWISE_OR:
295 case NFT_BITWISE_XOR:
296 err = nft_bitwise_init_bool(ctx, priv, tb);
297 break;
298 }
299
300 return err;
301}
302
303static int nft_bitwise_dump_mask_xor(struct sk_buff *skb,
304 const struct nft_bitwise *priv)
305{
306 if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
307 NFT_DATA_VALUE, priv->len) < 0)
308 return -1;
309
310 if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
311 NFT_DATA_VALUE, priv->len) < 0)
312 return -1;
313
314 return 0;
315}
316
317static int nft_bitwise_dump_shift(struct sk_buff *skb,
318 const struct nft_bitwise *priv)
319{
320 if (nft_data_dump(skb, NFTA_BITWISE_DATA, &priv->data,
321 NFT_DATA_VALUE, sizeof(u32)) < 0)
322 return -1;
323 return 0;
324}
325
326static int nft_bitwise_dump_bool(struct sk_buff *skb,
327 const struct nft_bitwise *priv)
328{
329 if (priv->sreg2) {
330 if (nft_dump_register(skb, NFTA_BITWISE_SREG2, priv->sreg2))
331 return -1;
332 } else {
333 if (nft_data_dump(skb, NFTA_BITWISE_DATA, &priv->data,
334 NFT_DATA_VALUE, sizeof(u32)) < 0)
335 return -1;
336 }
337
338 return 0;
339}
340
341static int nft_bitwise_dump(struct sk_buff *skb,
342 const struct nft_expr *expr, bool reset)
343{
344 const struct nft_bitwise *priv = nft_expr_priv(expr);
345 int err = 0;
346
347 if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
348 return -1;
349 if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
350 return -1;
351 if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
352 return -1;
353 if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(priv->op)))
354 return -1;
355
356 switch (priv->op) {
357 case NFT_BITWISE_MASK_XOR:
358 err = nft_bitwise_dump_mask_xor(skb, priv);
359 break;
360 case NFT_BITWISE_LSHIFT:
361 case NFT_BITWISE_RSHIFT:
362 err = nft_bitwise_dump_shift(skb, priv);
363 break;
364 case NFT_BITWISE_AND:
365 case NFT_BITWISE_OR:
366 case NFT_BITWISE_XOR:
367 err = nft_bitwise_dump_bool(skb, priv);
368 break;
369 }
370
371 return err;
372}
373
374static struct nft_data zero;
375
376static int nft_bitwise_offload(struct nft_offload_ctx *ctx,
377 struct nft_flow_rule *flow,
378 const struct nft_expr *expr)
379{
380 const struct nft_bitwise *priv = nft_expr_priv(expr);
381 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
382
383 if (priv->op != NFT_BITWISE_MASK_XOR)
384 return -EOPNOTSUPP;
385
386 if (memcmp(&priv->xor, &zero, sizeof(priv->xor)) ||
387 priv->sreg != priv->dreg || priv->len != reg->len)
388 return -EOPNOTSUPP;
389
390 memcpy(®->mask, &priv->mask, sizeof(priv->mask));
391
392 return 0;
393}
394
395static const struct nft_expr_ops nft_bitwise_ops = {
396 .type = &nft_bitwise_type,
397 .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
398 .eval = nft_bitwise_eval,
399 .init = nft_bitwise_init,
400 .dump = nft_bitwise_dump,
401 .offload = nft_bitwise_offload,
402};
403
404static int
405nft_bitwise_extract_u32_data(const struct nlattr * const tb, u32 *out)
406{
407 struct nft_data data;
408 struct nft_data_desc desc = {
409 .type = NFT_DATA_VALUE,
410 .size = sizeof(data),
411 .len = sizeof(u32),
412 };
413 int err;
414
415 err = nft_data_init(NULL, &data, &desc, tb);
416 if (err < 0)
417 return err;
418
419 *out = data.data[0];
420
421 return 0;
422}
423
424static int nft_bitwise_fast_init(const struct nft_ctx *ctx,
425 const struct nft_expr *expr,
426 const struct nlattr * const tb[])
427{
428 struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
429 int err;
430
431 err = nft_parse_register_load(ctx, tb[NFTA_BITWISE_SREG], &priv->sreg,
432 sizeof(u32));
433 if (err < 0)
434 return err;
435
436 err = nft_parse_register_store(ctx, tb[NFTA_BITWISE_DREG], &priv->dreg,
437 NULL, NFT_DATA_VALUE, sizeof(u32));
438 if (err < 0)
439 return err;
440
441 if (tb[NFTA_BITWISE_DATA] ||
442 tb[NFTA_BITWISE_SREG2])
443 return -EINVAL;
444
445 if (!tb[NFTA_BITWISE_MASK] ||
446 !tb[NFTA_BITWISE_XOR])
447 return -EINVAL;
448
449 err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_MASK], &priv->mask);
450 if (err < 0)
451 return err;
452
453 err = nft_bitwise_extract_u32_data(tb[NFTA_BITWISE_XOR], &priv->xor);
454 if (err < 0)
455 return err;
456
457 return 0;
458}
459
460static int
461nft_bitwise_fast_dump(struct sk_buff *skb,
462 const struct nft_expr *expr, bool reset)
463{
464 const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
465 struct nft_data data;
466
467 if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
468 return -1;
469 if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
470 return -1;
471 if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(sizeof(u32))))
472 return -1;
473 if (nla_put_be32(skb, NFTA_BITWISE_OP, htonl(NFT_BITWISE_MASK_XOR)))
474 return -1;
475
476 data.data[0] = priv->mask;
477 if (nft_data_dump(skb, NFTA_BITWISE_MASK, &data,
478 NFT_DATA_VALUE, sizeof(u32)) < 0)
479 return -1;
480
481 data.data[0] = priv->xor;
482 if (nft_data_dump(skb, NFTA_BITWISE_XOR, &data,
483 NFT_DATA_VALUE, sizeof(u32)) < 0)
484 return -1;
485
486 return 0;
487}
488
489static int nft_bitwise_fast_offload(struct nft_offload_ctx *ctx,
490 struct nft_flow_rule *flow,
491 const struct nft_expr *expr)
492{
493 const struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
494 struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
495
496 if (priv->xor || priv->sreg != priv->dreg || reg->len != sizeof(u32))
497 return -EOPNOTSUPP;
498
499 reg->mask.data[0] = priv->mask;
500 return 0;
501}
502
503const struct nft_expr_ops nft_bitwise_fast_ops = {
504 .type = &nft_bitwise_type,
505 .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise_fast_expr)),
506 .eval = NULL, /* inlined */
507 .init = nft_bitwise_fast_init,
508 .dump = nft_bitwise_fast_dump,
509 .offload = nft_bitwise_fast_offload,
510};
511
512static const struct nft_expr_ops *
513nft_bitwise_select_ops(const struct nft_ctx *ctx,
514 const struct nlattr * const tb[])
515{
516 int err;
517 u32 len;
518
519 if (!tb[NFTA_BITWISE_LEN] ||
520 !tb[NFTA_BITWISE_SREG] ||
521 !tb[NFTA_BITWISE_DREG])
522 return ERR_PTR(-EINVAL);
523
524 err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
525 if (err < 0)
526 return ERR_PTR(err);
527
528 if (len != sizeof(u32))
529 return &nft_bitwise_ops;
530
531 if (tb[NFTA_BITWISE_OP] &&
532 ntohl(nla_get_be32(tb[NFTA_BITWISE_OP])) != NFT_BITWISE_MASK_XOR)
533 return &nft_bitwise_ops;
534
535 return &nft_bitwise_fast_ops;
536}
537
538struct nft_expr_type nft_bitwise_type __read_mostly = {
539 .name = "bitwise",
540 .select_ops = nft_bitwise_select_ops,
541 .policy = nft_bitwise_policy,
542 .maxattr = NFTA_BITWISE_MAX,
543 .owner = THIS_MODULE,
544};