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-rw-r--r--crypto/cipher.c447
1 files changed, 3 insertions, 444 deletions
diff --git a/crypto/cipher.c b/crypto/cipher.c
index 9e03701cfdcc..333aab2f0277 100644
--- a/crypto/cipher.c
+++ b/crypto/cipher.c
@@ -12,274 +12,13 @@
12 * any later version. 12 * any later version.
13 * 13 *
14 */ 14 */
15#include <linux/compiler.h> 15
16#include <linux/kernel.h> 16#include <linux/kernel.h>
17#include <linux/crypto.h> 17#include <linux/crypto.h>
18#include <linux/errno.h> 18#include <linux/errno.h>
19#include <linux/mm.h> 19#include <linux/scatterlist.h>
20#include <linux/slab.h>
21#include <linux/string.h> 20#include <linux/string.h>
22#include <asm/scatterlist.h>
23#include "internal.h" 21#include "internal.h"
24#include "scatterwalk.h"
25
26struct cipher_alg_compat {
27 unsigned int cia_min_keysize;
28 unsigned int cia_max_keysize;
29 int (*cia_setkey)(struct crypto_tfm *tfm, const u8 *key,
30 unsigned int keylen);
31 void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
32 void (*cia_decrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
33
34 unsigned int (*cia_encrypt_ecb)(const struct cipher_desc *desc,
35 u8 *dst, const u8 *src,
36 unsigned int nbytes);
37 unsigned int (*cia_decrypt_ecb)(const struct cipher_desc *desc,
38 u8 *dst, const u8 *src,
39 unsigned int nbytes);
40 unsigned int (*cia_encrypt_cbc)(const struct cipher_desc *desc,
41 u8 *dst, const u8 *src,
42 unsigned int nbytes);
43 unsigned int (*cia_decrypt_cbc)(const struct cipher_desc *desc,
44 u8 *dst, const u8 *src,
45 unsigned int nbytes);
46};
47
48static inline void xor_64(u8 *a, const u8 *b)
49{
50 ((u32 *)a)[0] ^= ((u32 *)b)[0];
51 ((u32 *)a)[1] ^= ((u32 *)b)[1];
52}
53
54static inline void xor_128(u8 *a, const u8 *b)
55{
56 ((u32 *)a)[0] ^= ((u32 *)b)[0];
57 ((u32 *)a)[1] ^= ((u32 *)b)[1];
58 ((u32 *)a)[2] ^= ((u32 *)b)[2];
59 ((u32 *)a)[3] ^= ((u32 *)b)[3];
60}
61
62static unsigned int crypt_slow(const struct cipher_desc *desc,
63 struct scatter_walk *in,
64 struct scatter_walk *out, unsigned int bsize)
65{
66 unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
67 u8 buffer[bsize * 2 + alignmask];
68 u8 *src = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
69 u8 *dst = src + bsize;
70
71 scatterwalk_copychunks(src, in, bsize, 0);
72 desc->prfn(desc, dst, src, bsize);
73 scatterwalk_copychunks(dst, out, bsize, 1);
74
75 return bsize;
76}
77
78static inline unsigned int crypt_fast(const struct cipher_desc *desc,
79 struct scatter_walk *in,
80 struct scatter_walk *out,
81 unsigned int nbytes, u8 *tmp)
82{
83 u8 *src, *dst;
84 u8 *real_src, *real_dst;
85
86 real_src = scatterwalk_map(in, 0);
87 real_dst = scatterwalk_map(out, 1);
88
89 src = real_src;
90 dst = scatterwalk_samebuf(in, out) ? src : real_dst;
91
92 if (tmp) {
93 memcpy(tmp, src, nbytes);
94 src = tmp;
95 dst = tmp;
96 }
97
98 nbytes = desc->prfn(desc, dst, src, nbytes);
99
100 if (tmp)
101 memcpy(real_dst, tmp, nbytes);
102
103 scatterwalk_unmap(real_src, 0);
104 scatterwalk_unmap(real_dst, 1);
105
106 scatterwalk_advance(in, nbytes);
107 scatterwalk_advance(out, nbytes);
108
109 return nbytes;
110}
111
112/*
113 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
114 * multiple page boundaries by using temporary blocks. In user context,
115 * the kernel is given a chance to schedule us once per page.
116 */
117static int crypt(const struct cipher_desc *desc,
118 struct scatterlist *dst,
119 struct scatterlist *src,
120 unsigned int nbytes)
121{
122 struct scatter_walk walk_in, walk_out;
123 struct crypto_tfm *tfm = desc->tfm;
124 const unsigned int bsize = crypto_tfm_alg_blocksize(tfm);
125 unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
126 unsigned long buffer = 0;
127
128 if (!nbytes)
129 return 0;
130
131 if (nbytes % bsize) {
132 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
133 return -EINVAL;
134 }
135
136 scatterwalk_start(&walk_in, src);
137 scatterwalk_start(&walk_out, dst);
138
139 for(;;) {
140 unsigned int n = nbytes;
141 u8 *tmp = NULL;
142
143 if (!scatterwalk_aligned(&walk_in, alignmask) ||
144 !scatterwalk_aligned(&walk_out, alignmask)) {
145 if (!buffer) {
146 buffer = __get_free_page(GFP_ATOMIC);
147 if (!buffer)
148 n = 0;
149 }
150 tmp = (u8 *)buffer;
151 }
152
153 n = scatterwalk_clamp(&walk_in, n);
154 n = scatterwalk_clamp(&walk_out, n);
155
156 if (likely(n >= bsize))
157 n = crypt_fast(desc, &walk_in, &walk_out, n, tmp);
158 else
159 n = crypt_slow(desc, &walk_in, &walk_out, bsize);
160
161 nbytes -= n;
162
163 scatterwalk_done(&walk_in, 0, nbytes);
164 scatterwalk_done(&walk_out, 1, nbytes);
165
166 if (!nbytes)
167 break;
168
169 crypto_yield(tfm->crt_flags);
170 }
171
172 if (buffer)
173 free_page(buffer);
174
175 return 0;
176}
177
178static int crypt_iv_unaligned(struct cipher_desc *desc,
179 struct scatterlist *dst,
180 struct scatterlist *src,
181 unsigned int nbytes)
182{
183 struct crypto_tfm *tfm = desc->tfm;
184 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
185 u8 *iv = desc->info;
186
187 if (unlikely(((unsigned long)iv & alignmask))) {
188 unsigned int ivsize = tfm->crt_cipher.cit_ivsize;
189 u8 buffer[ivsize + alignmask];
190 u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
191 int err;
192
193 desc->info = memcpy(tmp, iv, ivsize);
194 err = crypt(desc, dst, src, nbytes);
195 memcpy(iv, tmp, ivsize);
196
197 return err;
198 }
199
200 return crypt(desc, dst, src, nbytes);
201}
202
203static unsigned int cbc_process_encrypt(const struct cipher_desc *desc,
204 u8 *dst, const u8 *src,
205 unsigned int nbytes)
206{
207 struct crypto_tfm *tfm = desc->tfm;
208 void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block;
209 int bsize = crypto_tfm_alg_blocksize(tfm);
210
211 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
212 u8 *iv = desc->info;
213 unsigned int done = 0;
214
215 nbytes -= bsize;
216
217 do {
218 xor(iv, src);
219 fn(tfm, dst, iv);
220 memcpy(iv, dst, bsize);
221
222 src += bsize;
223 dst += bsize;
224 } while ((done += bsize) <= nbytes);
225
226 return done;
227}
228
229static unsigned int cbc_process_decrypt(const struct cipher_desc *desc,
230 u8 *dst, const u8 *src,
231 unsigned int nbytes)
232{
233 struct crypto_tfm *tfm = desc->tfm;
234 void (*xor)(u8 *, const u8 *) = tfm->crt_u.cipher.cit_xor_block;
235 int bsize = crypto_tfm_alg_blocksize(tfm);
236 unsigned long alignmask = crypto_tfm_alg_alignmask(desc->tfm);
237
238 u8 stack[src == dst ? bsize + alignmask : 0];
239 u8 *buf = (u8 *)ALIGN((unsigned long)stack, alignmask + 1);
240 u8 **dst_p = src == dst ? &buf : &dst;
241
242 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
243 u8 *iv = desc->info;
244 unsigned int done = 0;
245
246 nbytes -= bsize;
247
248 do {
249 u8 *tmp_dst = *dst_p;
250
251 fn(tfm, tmp_dst, src);
252 xor(tmp_dst, iv);
253 memcpy(iv, src, bsize);
254 if (tmp_dst != dst)
255 memcpy(dst, tmp_dst, bsize);
256
257 src += bsize;
258 dst += bsize;
259 } while ((done += bsize) <= nbytes);
260
261 return done;
262}
263
264static unsigned int ecb_process(const struct cipher_desc *desc, u8 *dst,
265 const u8 *src, unsigned int nbytes)
266{
267 struct crypto_tfm *tfm = desc->tfm;
268 int bsize = crypto_tfm_alg_blocksize(tfm);
269 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) = desc->crfn;
270 unsigned int done = 0;
271
272 nbytes -= bsize;
273
274 do {
275 fn(tfm, dst, src);
276
277 src += bsize;
278 dst += bsize;
279 } while ((done += bsize) <= nbytes);
280
281 return done;
282}
283 22
284static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen) 23static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
285{ 24{
@@ -293,122 +32,6 @@ static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
293 return cia->cia_setkey(tfm, key, keylen); 32 return cia->cia_setkey(tfm, key, keylen);
294} 33}
295 34
296static int ecb_encrypt(struct crypto_tfm *tfm,
297 struct scatterlist *dst,
298 struct scatterlist *src, unsigned int nbytes)
299{
300 struct cipher_desc desc;
301 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
302
303 desc.tfm = tfm;
304 desc.crfn = cipher->cia_encrypt;
305 desc.prfn = cipher->cia_encrypt_ecb ?: ecb_process;
306
307 return crypt(&desc, dst, src, nbytes);
308}
309
310static int ecb_decrypt(struct crypto_tfm *tfm,
311 struct scatterlist *dst,
312 struct scatterlist *src,
313 unsigned int nbytes)
314{
315 struct cipher_desc desc;
316 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
317
318 desc.tfm = tfm;
319 desc.crfn = cipher->cia_decrypt;
320 desc.prfn = cipher->cia_decrypt_ecb ?: ecb_process;
321
322 return crypt(&desc, dst, src, nbytes);
323}
324
325static int cbc_encrypt(struct crypto_tfm *tfm,
326 struct scatterlist *dst,
327 struct scatterlist *src,
328 unsigned int nbytes)
329{
330 struct cipher_desc desc;
331 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
332
333 desc.tfm = tfm;
334 desc.crfn = cipher->cia_encrypt;
335 desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
336 desc.info = tfm->crt_cipher.cit_iv;
337
338 return crypt(&desc, dst, src, nbytes);
339}
340
341static int cbc_encrypt_iv(struct crypto_tfm *tfm,
342 struct scatterlist *dst,
343 struct scatterlist *src,
344 unsigned int nbytes, u8 *iv)
345{
346 struct cipher_desc desc;
347 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
348
349 desc.tfm = tfm;
350 desc.crfn = cipher->cia_encrypt;
351 desc.prfn = cipher->cia_encrypt_cbc ?: cbc_process_encrypt;
352 desc.info = iv;
353
354 return crypt_iv_unaligned(&desc, dst, src, nbytes);
355}
356
357static int cbc_decrypt(struct crypto_tfm *tfm,
358 struct scatterlist *dst,
359 struct scatterlist *src,
360 unsigned int nbytes)
361{
362 struct cipher_desc desc;
363 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
364
365 desc.tfm = tfm;
366 desc.crfn = cipher->cia_decrypt;
367 desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
368 desc.info = tfm->crt_cipher.cit_iv;
369
370 return crypt(&desc, dst, src, nbytes);
371}
372
373static int cbc_decrypt_iv(struct crypto_tfm *tfm,
374 struct scatterlist *dst,
375 struct scatterlist *src,
376 unsigned int nbytes, u8 *iv)
377{
378 struct cipher_desc desc;
379 struct cipher_alg_compat *cipher = (void *)&tfm->__crt_alg->cra_cipher;
380
381 desc.tfm = tfm;
382 desc.crfn = cipher->cia_decrypt;
383 desc.prfn = cipher->cia_decrypt_cbc ?: cbc_process_decrypt;
384 desc.info = iv;
385
386 return crypt_iv_unaligned(&desc, dst, src, nbytes);
387}
388
389static int nocrypt(struct crypto_tfm *tfm,
390 struct scatterlist *dst,
391 struct scatterlist *src,
392 unsigned int nbytes)
393{
394 return -ENOSYS;
395}
396
397static int nocrypt_iv(struct crypto_tfm *tfm,
398 struct scatterlist *dst,
399 struct scatterlist *src,
400 unsigned int nbytes, u8 *iv)
401{
402 return -ENOSYS;
403}
404
405int crypto_init_cipher_flags(struct crypto_tfm *tfm, u32 flags)
406{
407 u32 mode = flags & CRYPTO_TFM_MODE_MASK;
408 tfm->crt_cipher.cit_mode = mode ? mode : CRYPTO_TFM_MODE_ECB;
409 return 0;
410}
411
412static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *, 35static void cipher_crypt_unaligned(void (*fn)(struct crypto_tfm *, u8 *,
413 const u8 *), 36 const u8 *),
414 struct crypto_tfm *tfm, 37 struct crypto_tfm *tfm,
@@ -454,7 +77,6 @@ static void cipher_decrypt_unaligned(struct crypto_tfm *tfm,
454 77
455int crypto_init_cipher_ops(struct crypto_tfm *tfm) 78int crypto_init_cipher_ops(struct crypto_tfm *tfm)
456{ 79{
457 int ret = 0;
458 struct cipher_tfm *ops = &tfm->crt_cipher; 80 struct cipher_tfm *ops = &tfm->crt_cipher;
459 struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher; 81 struct cipher_alg *cipher = &tfm->__crt_alg->cra_cipher;
460 82
@@ -464,70 +86,7 @@ int crypto_init_cipher_ops(struct crypto_tfm *tfm)
464 ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ? 86 ops->cit_decrypt_one = crypto_tfm_alg_alignmask(tfm) ?
465 cipher_decrypt_unaligned : cipher->cia_decrypt; 87 cipher_decrypt_unaligned : cipher->cia_decrypt;
466 88
467 switch (tfm->crt_cipher.cit_mode) { 89 return 0;
468 case CRYPTO_TFM_MODE_ECB:
469 ops->cit_encrypt = ecb_encrypt;
470 ops->cit_decrypt = ecb_decrypt;
471 ops->cit_encrypt_iv = nocrypt_iv;
472 ops->cit_decrypt_iv = nocrypt_iv;
473 break;
474
475 case CRYPTO_TFM_MODE_CBC:
476 ops->cit_encrypt = cbc_encrypt;
477 ops->cit_decrypt = cbc_decrypt;
478 ops->cit_encrypt_iv = cbc_encrypt_iv;
479 ops->cit_decrypt_iv = cbc_decrypt_iv;
480 break;
481
482 case CRYPTO_TFM_MODE_CFB:
483 ops->cit_encrypt = nocrypt;
484 ops->cit_decrypt = nocrypt;
485 ops->cit_encrypt_iv = nocrypt_iv;
486 ops->cit_decrypt_iv = nocrypt_iv;
487 break;
488
489 case CRYPTO_TFM_MODE_CTR:
490 ops->cit_encrypt = nocrypt;
491 ops->cit_decrypt = nocrypt;
492 ops->cit_encrypt_iv = nocrypt_iv;
493 ops->cit_decrypt_iv = nocrypt_iv;
494 break;
495
496 default:
497 BUG();
498 }
499
500 if (ops->cit_mode == CRYPTO_TFM_MODE_CBC) {
501 unsigned long align;
502 unsigned long addr;
503
504 switch (crypto_tfm_alg_blocksize(tfm)) {
505 case 8:
506 ops->cit_xor_block = xor_64;
507 break;
508
509 case 16:
510 ops->cit_xor_block = xor_128;
511 break;
512
513 default:
514 printk(KERN_WARNING "%s: block size %u not supported\n",
515 crypto_tfm_alg_name(tfm),
516 crypto_tfm_alg_blocksize(tfm));
517 ret = -EINVAL;
518 goto out;
519 }
520
521 ops->cit_ivsize = crypto_tfm_alg_blocksize(tfm);
522 align = crypto_tfm_alg_alignmask(tfm) + 1;
523 addr = (unsigned long)crypto_tfm_ctx(tfm);
524 addr = ALIGN(addr, align);
525 addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
526 ops->cit_iv = (void *)addr;
527 }
528
529out:
530 return ret;
531} 90}
532 91
533void crypto_exit_cipher_ops(struct crypto_tfm *tfm) 92void crypto_exit_cipher_ops(struct crypto_tfm *tfm)
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-23 19:28:46 -0500