1 /*
2 * WPA Supplicant / Crypto wrapper for internal crypto implementation
3 * Copyright (c) 2006-2007, Jouni Malinen <j@w1.fi>
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 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15 #include "includes.h"
16
17 #include "common.h"
18 #include "crypto.h"
19 #include "md5.h"
20 #include "sha1.h"
21 #include "rc4.h"
22 #include "aes.h"
23 #include "tls/rsa.h"
24 #include "tls/bignum.h"
25 #include "tls/asn1.h"
26
27
28 #ifdef CONFIG_CRYPTO_INTERNAL
29
30 #ifdef CONFIG_TLS_INTERNAL
31
32 /* from des.c */
33 struct des3_key_s {
34 u32 ek[3][32];
35 u32 dk[3][32];
36 };
37
38 void des3_key_setup(const u8 *key, struct des3_key_s *dkey);
39 void des3_encrypt(const u8 *plain, const struct des3_key_s *key, u8 *crypt);
40 void des3_decrypt(const u8 *crypt, const struct des3_key_s *key, u8 *plain);
41
42
43 struct MD5Context {
44 u32 buf[4];
45 u32 bits[2];
46 u8 in[64];
47 };
48
49 struct SHA1Context {
50 u32 state[5];
51 u32 count[2];
52 unsigned char buffer[64];
53 };
54
55
56 struct crypto_hash {
57 enum crypto_hash_alg alg;
58 union {
59 struct MD5Context md5;
60 struct SHA1Context sha1;
61 } u;
62 u8 key[64];
63 size_t key_len;
64 };
65
66
crypto_hash_init(enum crypto_hash_alg alg,const u8 * key,size_t key_len)67 struct crypto_hash * crypto_hash_init(enum crypto_hash_alg alg, const u8 *key,
68 size_t key_len)
69 {
70 struct crypto_hash *ctx;
71 u8 k_pad[64];
72 u8 tk[20];
73 size_t i;
74
75 ctx = os_zalloc(sizeof(*ctx));
76 if (ctx == NULL)
77 return NULL;
78
79 ctx->alg = alg;
80
81 switch (alg) {
82 case CRYPTO_HASH_ALG_MD5:
83 MD5Init(&ctx->u.md5);
84 break;
85 case CRYPTO_HASH_ALG_SHA1:
86 SHA1Init(&ctx->u.sha1);
87 break;
88 case CRYPTO_HASH_ALG_HMAC_MD5:
89 if (key_len > sizeof(k_pad)) {
90 MD5Init(&ctx->u.md5);
91 MD5Update(&ctx->u.md5, key, key_len);
92 MD5Final(tk, &ctx->u.md5);
93 key = tk;
94 key_len = 16;
95 }
96 os_memcpy(ctx->key, key, key_len);
97 ctx->key_len = key_len;
98
99 os_memcpy(k_pad, key, key_len);
100 os_memset(k_pad + key_len, 0, sizeof(k_pad) - key_len);
101 for (i = 0; i < sizeof(k_pad); i++)
102 k_pad[i] ^= 0x36;
103 MD5Init(&ctx->u.md5);
104 MD5Update(&ctx->u.md5, k_pad, sizeof(k_pad));
105 break;
106 case CRYPTO_HASH_ALG_HMAC_SHA1:
107 if (key_len > sizeof(k_pad)) {
108 SHA1Init(&ctx->u.sha1);
109 SHA1Update(&ctx->u.sha1, key, key_len);
110 SHA1Final(tk, &ctx->u.sha1);
111 key = tk;
112 key_len = 20;
113 }
114 os_memcpy(ctx->key, key, key_len);
115 ctx->key_len = key_len;
116
117 os_memcpy(k_pad, key, key_len);
118 os_memset(k_pad + key_len, 0, sizeof(k_pad) - key_len);
119 for (i = 0; i < sizeof(k_pad); i++)
120 k_pad[i] ^= 0x36;
121 SHA1Init(&ctx->u.sha1);
122 SHA1Update(&ctx->u.sha1, k_pad, sizeof(k_pad));
123 break;
124 default:
125 os_free(ctx);
126 return NULL;
127 }
128
129 return ctx;
130 }
131
132
crypto_hash_update(struct crypto_hash * ctx,const u8 * data,size_t len)133 void crypto_hash_update(struct crypto_hash *ctx, const u8 *data, size_t len)
134 {
135 if (ctx == NULL)
136 return;
137
138 switch (ctx->alg) {
139 case CRYPTO_HASH_ALG_MD5:
140 case CRYPTO_HASH_ALG_HMAC_MD5:
141 MD5Update(&ctx->u.md5, data, len);
142 break;
143 case CRYPTO_HASH_ALG_SHA1:
144 case CRYPTO_HASH_ALG_HMAC_SHA1:
145 SHA1Update(&ctx->u.sha1, data, len);
146 break;
147 }
148 }
149
150
crypto_hash_finish(struct crypto_hash * ctx,u8 * mac,size_t * len)151 int crypto_hash_finish(struct crypto_hash *ctx, u8 *mac, size_t *len)
152 {
153 u8 k_pad[64];
154 size_t i;
155
156 if (ctx == NULL)
157 return -2;
158
159 if (mac == NULL || len == NULL) {
160 os_free(ctx);
161 return 0;
162 }
163
164 switch (ctx->alg) {
165 case CRYPTO_HASH_ALG_MD5:
166 if (*len < 16) {
167 *len = 16;
168 os_free(ctx);
169 return -1;
170 }
171 *len = 16;
172 MD5Final(mac, &ctx->u.md5);
173 break;
174 case CRYPTO_HASH_ALG_SHA1:
175 if (*len < 20) {
176 *len = 20;
177 os_free(ctx);
178 return -1;
179 }
180 *len = 20;
181 SHA1Final(mac, &ctx->u.sha1);
182 break;
183 case CRYPTO_HASH_ALG_HMAC_MD5:
184 if (*len < 16) {
185 *len = 16;
186 os_free(ctx);
187 return -1;
188 }
189 *len = 16;
190
191 MD5Final(mac, &ctx->u.md5);
192
193 os_memcpy(k_pad, ctx->key, ctx->key_len);
194 os_memset(k_pad + ctx->key_len, 0,
195 sizeof(k_pad) - ctx->key_len);
196 for (i = 0; i < sizeof(k_pad); i++)
197 k_pad[i] ^= 0x5c;
198 MD5Init(&ctx->u.md5);
199 MD5Update(&ctx->u.md5, k_pad, sizeof(k_pad));
200 MD5Update(&ctx->u.md5, mac, 16);
201 MD5Final(mac, &ctx->u.md5);
202 break;
203 case CRYPTO_HASH_ALG_HMAC_SHA1:
204 if (*len < 20) {
205 *len = 20;
206 os_free(ctx);
207 return -1;
208 }
209 *len = 20;
210
211 SHA1Final(mac, &ctx->u.sha1);
212
213 os_memcpy(k_pad, ctx->key, ctx->key_len);
214 os_memset(k_pad + ctx->key_len, 0,
215 sizeof(k_pad) - ctx->key_len);
216 for (i = 0; i < sizeof(k_pad); i++)
217 k_pad[i] ^= 0x5c;
218 SHA1Init(&ctx->u.sha1);
219 SHA1Update(&ctx->u.sha1, k_pad, sizeof(k_pad));
220 SHA1Update(&ctx->u.sha1, mac, 20);
221 SHA1Final(mac, &ctx->u.sha1);
222 break;
223 }
224
225 os_free(ctx);
226
227 return 0;
228 }
229
230
231 struct crypto_cipher {
232 enum crypto_cipher_alg alg;
233 union {
234 struct {
235 size_t used_bytes;
236 u8 key[16];
237 size_t keylen;
238 } rc4;
239 struct {
240 u8 cbc[32];
241 size_t block_size;
242 void *ctx_enc;
243 void *ctx_dec;
244 } aes;
245 struct {
246 struct des3_key_s key;
247 u8 cbc[8];
248 } des3;
249 } u;
250 };
251
252
crypto_cipher_init(enum crypto_cipher_alg alg,const u8 * iv,const u8 * key,size_t key_len)253 struct crypto_cipher * crypto_cipher_init(enum crypto_cipher_alg alg,
254 const u8 *iv, const u8 *key,
255 size_t key_len)
256 {
257 struct crypto_cipher *ctx;
258
259 ctx = os_zalloc(sizeof(*ctx));
260 if (ctx == NULL)
261 return NULL;
262
263 ctx->alg = alg;
264
265 switch (alg) {
266 case CRYPTO_CIPHER_ALG_RC4:
267 if (key_len > sizeof(ctx->u.rc4.key)) {
268 os_free(ctx);
269 return NULL;
270 }
271 ctx->u.rc4.keylen = key_len;
272 os_memcpy(ctx->u.rc4.key, key, key_len);
273 break;
274 case CRYPTO_CIPHER_ALG_AES:
275 if (key_len > sizeof(ctx->u.aes.cbc)) {
276 os_free(ctx);
277 return NULL;
278 }
279 ctx->u.aes.ctx_enc = aes_encrypt_init(key, key_len);
280 if (ctx->u.aes.ctx_enc == NULL) {
281 os_free(ctx);
282 return NULL;
283 }
284 ctx->u.aes.ctx_dec = aes_decrypt_init(key, key_len);
285 if (ctx->u.aes.ctx_dec == NULL) {
286 aes_encrypt_deinit(ctx->u.aes.ctx_enc);
287 os_free(ctx);
288 return NULL;
289 }
290 ctx->u.aes.block_size = key_len;
291 os_memcpy(ctx->u.aes.cbc, iv, ctx->u.aes.block_size);
292 break;
293 case CRYPTO_CIPHER_ALG_3DES:
294 if (key_len != 24) {
295 os_free(ctx);
296 return NULL;
297 }
298 des3_key_setup(key, &ctx->u.des3.key);
299 os_memcpy(ctx->u.des3.cbc, iv, 8);
300 break;
301 default:
302 os_free(ctx);
303 return NULL;
304 }
305
306 return ctx;
307 }
308
309
crypto_cipher_encrypt(struct crypto_cipher * ctx,const u8 * plain,u8 * crypt,size_t len)310 int crypto_cipher_encrypt(struct crypto_cipher *ctx, const u8 *plain,
311 u8 *crypt, size_t len)
312 {
313 size_t i, j, blocks;
314
315 switch (ctx->alg) {
316 case CRYPTO_CIPHER_ALG_RC4:
317 if (plain != crypt)
318 os_memcpy(crypt, plain, len);
319 rc4_skip(ctx->u.rc4.key, ctx->u.rc4.keylen,
320 ctx->u.rc4.used_bytes, crypt, len);
321 ctx->u.rc4.used_bytes += len;
322 break;
323 case CRYPTO_CIPHER_ALG_AES:
324 if (len % ctx->u.aes.block_size)
325 return -1;
326 blocks = len / ctx->u.aes.block_size;
327 for (i = 0; i < blocks; i++) {
328 for (j = 0; j < ctx->u.aes.block_size; j++)
329 ctx->u.aes.cbc[j] ^= plain[j];
330 aes_encrypt(ctx->u.aes.ctx_enc, ctx->u.aes.cbc,
331 ctx->u.aes.cbc);
332 os_memcpy(crypt, ctx->u.aes.cbc,
333 ctx->u.aes.block_size);
334 plain += ctx->u.aes.block_size;
335 crypt += ctx->u.aes.block_size;
336 }
337 break;
338 case CRYPTO_CIPHER_ALG_3DES:
339 if (len % 8)
340 return -1;
341 blocks = len / 8;
342 for (i = 0; i < blocks; i++) {
343 for (j = 0; j < 8; j++)
344 ctx->u.des3.cbc[j] ^= plain[j];
345 des3_encrypt(ctx->u.des3.cbc, &ctx->u.des3.key,
346 ctx->u.des3.cbc);
347 os_memcpy(crypt, ctx->u.des3.cbc, 8);
348 plain += 8;
349 crypt += 8;
350 }
351 break;
352 default:
353 return -1;
354 }
355
356 return 0;
357 }
358
359
crypto_cipher_decrypt(struct crypto_cipher * ctx,const u8 * crypt,u8 * plain,size_t len)360 int crypto_cipher_decrypt(struct crypto_cipher *ctx, const u8 *crypt,
361 u8 *plain, size_t len)
362 {
363 size_t i, j, blocks;
364 u8 tmp[32];
365
366 switch (ctx->alg) {
367 case CRYPTO_CIPHER_ALG_RC4:
368 if (plain != crypt)
369 os_memcpy(plain, crypt, len);
370 rc4_skip(ctx->u.rc4.key, ctx->u.rc4.keylen,
371 ctx->u.rc4.used_bytes, plain, len);
372 ctx->u.rc4.used_bytes += len;
373 break;
374 case CRYPTO_CIPHER_ALG_AES:
375 if (len % ctx->u.aes.block_size)
376 return -1;
377 blocks = len / ctx->u.aes.block_size;
378 for (i = 0; i < blocks; i++) {
379 os_memcpy(tmp, crypt, ctx->u.aes.block_size);
380 aes_decrypt(ctx->u.aes.ctx_dec, crypt, plain);
381 for (j = 0; j < ctx->u.aes.block_size; j++)
382 plain[j] ^= ctx->u.aes.cbc[j];
383 os_memcpy(ctx->u.aes.cbc, tmp, ctx->u.aes.block_size);
384 plain += ctx->u.aes.block_size;
385 crypt += ctx->u.aes.block_size;
386 }
387 break;
388 case CRYPTO_CIPHER_ALG_3DES:
389 if (len % 8)
390 return -1;
391 blocks = len / 8;
392 for (i = 0; i < blocks; i++) {
393 os_memcpy(tmp, crypt, 8);
394 des3_decrypt(crypt, &ctx->u.des3.key, plain);
395 for (j = 0; j < 8; j++)
396 plain[j] ^= ctx->u.des3.cbc[j];
397 os_memcpy(ctx->u.des3.cbc, tmp, 8);
398 plain += 8;
399 crypt += 8;
400 }
401 break;
402 default:
403 return -1;
404 }
405
406 return 0;
407 }
408
409
crypto_cipher_deinit(struct crypto_cipher * ctx)410 void crypto_cipher_deinit(struct crypto_cipher *ctx)
411 {
412 switch (ctx->alg) {
413 case CRYPTO_CIPHER_ALG_AES:
414 aes_encrypt_deinit(ctx->u.aes.ctx_enc);
415 aes_decrypt_deinit(ctx->u.aes.ctx_dec);
416 break;
417 case CRYPTO_CIPHER_ALG_3DES:
418 break;
419 default:
420 break;
421 }
422 os_free(ctx);
423 }
424
425
426 /* Dummy structures; these are just typecast to struct crypto_rsa_key */
427 struct crypto_public_key;
428 struct crypto_private_key;
429
430
crypto_public_key_import(const u8 * key,size_t len)431 struct crypto_public_key * crypto_public_key_import(const u8 *key, size_t len)
432 {
433 return (struct crypto_public_key *)
434 crypto_rsa_import_public_key(key, len);
435 }
436
437
438 #ifdef EAP_TLS_FUNCS
439 static struct crypto_private_key *
crypto_pkcs8_key_import(const u8 * buf,size_t len)440 crypto_pkcs8_key_import(const u8 *buf, size_t len)
441 {
442 struct asn1_hdr hdr;
443 const u8 *pos, *end;
444 struct bignum *zero;
445 struct asn1_oid oid;
446 char obuf[80];
447
448 /* PKCS #8, Chapter 6 */
449
450 /* PrivateKeyInfo ::= SEQUENCE */
451 if (asn1_get_next(buf, len, &hdr) < 0 ||
452 hdr.class != ASN1_CLASS_UNIVERSAL ||
453 hdr.tag != ASN1_TAG_SEQUENCE) {
454 wpa_printf(MSG_DEBUG, "PKCS #8: Does not start with PKCS #8 "
455 "header (SEQUENCE); assume PKCS #8 not used");
456 return NULL;
457 }
458 pos = hdr.payload;
459 end = pos + hdr.length;
460
461 /* version Version (Version ::= INTEGER) */
462 if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
463 hdr.class != ASN1_CLASS_UNIVERSAL || hdr.tag != ASN1_TAG_INTEGER) {
464 wpa_printf(MSG_DEBUG, "PKCS #8: Expected INTEGER - found "
465 "class %d tag 0x%x; assume PKCS #8 not used",
466 hdr.class, hdr.tag);
467 return NULL;
468 }
469
470 zero = bignum_init();
471 if (zero == NULL)
472 return NULL;
473
474 if (bignum_set_unsigned_bin(zero, hdr.payload, hdr.length) < 0) {
475 wpa_printf(MSG_DEBUG, "PKCS #8: Failed to parse INTEGER");
476 bignum_deinit(zero);
477 return NULL;
478 }
479 pos = hdr.payload + hdr.length;
480
481 if (bignum_cmp_d(zero, 0) != 0) {
482 wpa_printf(MSG_DEBUG, "PKCS #8: Expected zero INTEGER in the "
483 "beginning of private key; not found; assume "
484 "PKCS #8 not used");
485 bignum_deinit(zero);
486 return NULL;
487 }
488 bignum_deinit(zero);
489
490 /* privateKeyAlgorithm PrivateKeyAlgorithmIdentifier
491 * (PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier) */
492 if (asn1_get_next(pos, len, &hdr) < 0 ||
493 hdr.class != ASN1_CLASS_UNIVERSAL ||
494 hdr.tag != ASN1_TAG_SEQUENCE) {
495 wpa_printf(MSG_DEBUG, "PKCS #8: Expected SEQUENCE "
496 "(AlgorithmIdentifier) - found class %d tag 0x%x; "
497 "assume PKCS #8 not used",
498 hdr.class, hdr.tag);
499 return NULL;
500 }
501
502 if (asn1_get_oid(hdr.payload, hdr.length, &oid, &pos)) {
503 wpa_printf(MSG_DEBUG, "PKCS #8: Failed to parse OID "
504 "(algorithm); assume PKCS #8 not used");
505 return NULL;
506 }
507
508 asn1_oid_to_str(&oid, obuf, sizeof(obuf));
509 wpa_printf(MSG_DEBUG, "PKCS #8: algorithm=%s", obuf);
510
511 if (oid.len != 7 ||
512 oid.oid[0] != 1 /* iso */ ||
513 oid.oid[1] != 2 /* member-body */ ||
514 oid.oid[2] != 840 /* us */ ||
515 oid.oid[3] != 113549 /* rsadsi */ ||
516 oid.oid[4] != 1 /* pkcs */ ||
517 oid.oid[5] != 1 /* pkcs-1 */ ||
518 oid.oid[6] != 1 /* rsaEncryption */) {
519 wpa_printf(MSG_DEBUG, "PKCS #8: Unsupported private key "
520 "algorithm %s", obuf);
521 return NULL;
522 }
523
524 pos = hdr.payload + hdr.length;
525
526 /* privateKey PrivateKey (PrivateKey ::= OCTET STRING) */
527 if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
528 hdr.class != ASN1_CLASS_UNIVERSAL ||
529 hdr.tag != ASN1_TAG_OCTETSTRING) {
530 wpa_printf(MSG_DEBUG, "PKCS #8: Expected OCTETSTRING "
531 "(privateKey) - found class %d tag 0x%x",
532 hdr.class, hdr.tag);
533 return NULL;
534 }
535 wpa_printf(MSG_DEBUG, "PKCS #8: Try to parse RSAPrivateKey");
536
537 return (struct crypto_private_key *)
538 crypto_rsa_import_private_key(hdr.payload, hdr.length);
539 }
540 #endif /* EAP_TLS_FUNCS */
541
542
crypto_private_key_import(const u8 * key,size_t len)543 struct crypto_private_key * crypto_private_key_import(const u8 *key,
544 size_t len)
545 {
546 struct crypto_private_key *res;
547
548 /* First, check for possible PKCS #8 encoding */
549 res = crypto_pkcs8_key_import(key, len);
550 if (res)
551 return res;
552
553 /* Not PKCS#8, so try to import PKCS #1 encoded RSA private key */
554 wpa_printf(MSG_DEBUG, "Trying to parse PKCS #1 encoded RSA private "
555 "key");
556 return (struct crypto_private_key *)
557 crypto_rsa_import_private_key(key, len);
558 }
559
560
crypto_public_key_from_cert(const u8 * buf,size_t len)561 struct crypto_public_key * crypto_public_key_from_cert(const u8 *buf,
562 size_t len)
563 {
564 /* No X.509 support in crypto_internal.c */
565 return NULL;
566 }
567
568
pkcs1_generate_encryption_block(u8 block_type,size_t modlen,const u8 * in,size_t inlen,u8 * out,size_t * outlen)569 static int pkcs1_generate_encryption_block(u8 block_type, size_t modlen,
570 const u8 *in, size_t inlen,
571 u8 *out, size_t *outlen)
572 {
573 size_t ps_len;
574 u8 *pos;
575
576 /*
577 * PKCS #1 v1.5, 8.1:
578 *
579 * EB = 00 || BT || PS || 00 || D
580 * BT = 00 or 01 for private-key operation; 02 for public-key operation
581 * PS = k-3-||D||; at least eight octets
582 * (BT=0: PS=0x00, BT=1: PS=0xff, BT=2: PS=pseudorandom non-zero)
583 * k = length of modulus in octets (modlen)
584 */
585
586 if (modlen < 12 || modlen > *outlen || inlen > modlen - 11) {
587 wpa_printf(MSG_DEBUG, "PKCS #1: %s - Invalid buffer "
588 "lengths (modlen=%lu outlen=%lu inlen=%lu)",
589 __func__, (unsigned long) modlen,
590 (unsigned long) *outlen,
591 (unsigned long) inlen);
592 return -1;
593 }
594
595 pos = out;
596 *pos++ = 0x00;
597 *pos++ = block_type; /* BT */
598 ps_len = modlen - inlen - 3;
599 switch (block_type) {
600 case 0:
601 os_memset(pos, 0x00, ps_len);
602 pos += ps_len;
603 break;
604 case 1:
605 os_memset(pos, 0xff, ps_len);
606 pos += ps_len;
607 break;
608 case 2:
609 if (os_get_random(pos, ps_len) < 0) {
610 wpa_printf(MSG_DEBUG, "PKCS #1: %s - Failed to get "
611 "random data for PS", __func__);
612 return -1;
613 }
614 while (ps_len--) {
615 if (*pos == 0x00)
616 *pos = 0x01;
617 pos++;
618 }
619 break;
620 default:
621 wpa_printf(MSG_DEBUG, "PKCS #1: %s - Unsupported block type "
622 "%d", __func__, block_type);
623 return -1;
624 }
625 *pos++ = 0x00;
626 os_memcpy(pos, in, inlen); /* D */
627
628 return 0;
629 }
630
631
crypto_rsa_encrypt_pkcs1(int block_type,struct crypto_rsa_key * key,int use_private,const u8 * in,size_t inlen,u8 * out,size_t * outlen)632 static int crypto_rsa_encrypt_pkcs1(int block_type, struct crypto_rsa_key *key,
633 int use_private,
634 const u8 *in, size_t inlen,
635 u8 *out, size_t *outlen)
636 {
637 size_t modlen;
638
639 modlen = crypto_rsa_get_modulus_len(key);
640
641 if (pkcs1_generate_encryption_block(block_type, modlen, in, inlen,
642 out, outlen) < 0)
643 return -1;
644
645 return crypto_rsa_exptmod(out, modlen, out, outlen, key, use_private);
646 }
647
648
crypto_public_key_encrypt_pkcs1_v15(struct crypto_public_key * key,const u8 * in,size_t inlen,u8 * out,size_t * outlen)649 int crypto_public_key_encrypt_pkcs1_v15(struct crypto_public_key *key,
650 const u8 *in, size_t inlen,
651 u8 *out, size_t *outlen)
652 {
653 return crypto_rsa_encrypt_pkcs1(2, (struct crypto_rsa_key *) key,
654 0, in, inlen, out, outlen);
655 }
656
657
crypto_private_key_decrypt_pkcs1_v15(struct crypto_private_key * key,const u8 * in,size_t inlen,u8 * out,size_t * outlen)658 int crypto_private_key_decrypt_pkcs1_v15(struct crypto_private_key *key,
659 const u8 *in, size_t inlen,
660 u8 *out, size_t *outlen)
661 {
662 struct crypto_rsa_key *rkey = (struct crypto_rsa_key *) key;
663 int res;
664 u8 *pos, *end;
665
666 res = crypto_rsa_exptmod(in, inlen, out, outlen, rkey, 1);
667 if (res)
668 return res;
669
670 if (*outlen < 2 || out[0] != 0 || out[1] != 2)
671 return -1;
672
673 /* Skip PS (pseudorandom non-zero octets) */
674 pos = out + 2;
675 end = out + *outlen;
676 while (*pos && pos < end)
677 pos++;
678 if (pos == end)
679 return -1;
680 pos++;
681
682 *outlen -= pos - out;
683
684 /* Strip PKCS #1 header */
685 os_memmove(out, pos, *outlen);
686
687 return 0;
688 }
689
690
crypto_private_key_sign_pkcs1(struct crypto_private_key * key,const u8 * in,size_t inlen,u8 * out,size_t * outlen)691 int crypto_private_key_sign_pkcs1(struct crypto_private_key *key,
692 const u8 *in, size_t inlen,
693 u8 *out, size_t *outlen)
694 {
695 return crypto_rsa_encrypt_pkcs1(1, (struct crypto_rsa_key *) key,
696 1, in, inlen, out, outlen);
697 }
698
699
crypto_public_key_free(struct crypto_public_key * key)700 void crypto_public_key_free(struct crypto_public_key *key)
701 {
702 crypto_rsa_free((struct crypto_rsa_key *) key);
703 }
704
705
crypto_private_key_free(struct crypto_private_key * key)706 void crypto_private_key_free(struct crypto_private_key *key)
707 {
708 crypto_rsa_free((struct crypto_rsa_key *) key);
709 }
710
711
crypto_public_key_decrypt_pkcs1(struct crypto_public_key * key,const u8 * crypt,size_t crypt_len,u8 * plain,size_t * plain_len)712 int crypto_public_key_decrypt_pkcs1(struct crypto_public_key *key,
713 const u8 *crypt, size_t crypt_len,
714 u8 *plain, size_t *plain_len)
715 {
716 size_t len;
717 u8 *pos;
718
719 len = *plain_len;
720 if (crypto_rsa_exptmod(crypt, crypt_len, plain, &len,
721 (struct crypto_rsa_key *) key, 0) < 0)
722 return -1;
723
724 /*
725 * PKCS #1 v1.5, 8.1:
726 *
727 * EB = 00 || BT || PS || 00 || D
728 * BT = 00 or 01
729 * PS = k-3-||D|| times (00 if BT=00) or (FF if BT=01)
730 * k = length of modulus in octets
731 */
732
733 if (len < 3 + 8 + 16 /* min hash len */ ||
734 plain[0] != 0x00 || (plain[1] != 0x00 && plain[1] != 0x01)) {
735 wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
736 "structure");
737 return -1;
738 }
739
740 pos = plain + 3;
741 if (plain[1] == 0x00) {
742 /* BT = 00 */
743 if (plain[2] != 0x00) {
744 wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature "
745 "PS (BT=00)");
746 return -1;
747 }
748 while (pos + 1 < plain + len && *pos == 0x00 && pos[1] == 0x00)
749 pos++;
750 } else {
751 /* BT = 01 */
752 if (plain[2] != 0xff) {
753 wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature "
754 "PS (BT=01)");
755 return -1;
756 }
757 while (pos < plain + len && *pos == 0xff)
758 pos++;
759 }
760
761 if (pos - plain - 2 < 8) {
762 /* PKCS #1 v1.5, 8.1: At least eight octets long PS */
763 wpa_printf(MSG_INFO, "LibTomCrypt: Too short signature "
764 "padding");
765 return -1;
766 }
767
768 if (pos + 16 /* min hash len */ >= plain + len || *pos != 0x00) {
769 wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
770 "structure (2)");
771 return -1;
772 }
773 pos++;
774 len -= pos - plain;
775
776 /* Strip PKCS #1 header */
777 os_memmove(plain, pos, len);
778 *plain_len = len;
779
780 return 0;
781 }
782
783
crypto_global_init(void)784 int crypto_global_init(void)
785 {
786 return 0;
787 }
788
789
crypto_global_deinit(void)790 void crypto_global_deinit(void)
791 {
792 }
793 #endif /* CONFIG_TLS_INTERNAL */
794
795
796 #if defined(EAP_FAST) || defined(CONFIG_WPS)
797
crypto_mod_exp(const u8 * base,size_t base_len,const u8 * power,size_t power_len,const u8 * modulus,size_t modulus_len,u8 * result,size_t * result_len)798 int crypto_mod_exp(const u8 *base, size_t base_len,
799 const u8 *power, size_t power_len,
800 const u8 *modulus, size_t modulus_len,
801 u8 *result, size_t *result_len)
802 {
803 struct bignum *bn_base, *bn_exp, *bn_modulus, *bn_result;
804 int ret = -1;
805
806 bn_base = bignum_init();
807 bn_exp = bignum_init();
808 bn_modulus = bignum_init();
809 bn_result = bignum_init();
810
811 if (bn_base == NULL || bn_exp == NULL || bn_modulus == NULL ||
812 bn_result == NULL)
813 goto error;
814
815 if (bignum_set_unsigned_bin(bn_base, base, base_len) < 0 ||
816 bignum_set_unsigned_bin(bn_exp, power, power_len) < 0 ||
817 bignum_set_unsigned_bin(bn_modulus, modulus, modulus_len) < 0)
818 goto error;
819
820 if (bignum_exptmod(bn_base, bn_exp, bn_modulus, bn_result) < 0)
821 goto error;
822
823 ret = bignum_get_unsigned_bin(bn_result, result, result_len);
824
825 error:
826 bignum_deinit(bn_base);
827 bignum_deinit(bn_exp);
828 bignum_deinit(bn_modulus);
829 bignum_deinit(bn_result);
830 return ret;
831 }
832
833 #endif /* EAP_FAST || CONFIG_WPS */
834
835
836 #endif /* CONFIG_CRYPTO_INTERNAL */
837