1/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
2 * project 1999.
3 */
4/* ====================================================================
5 * Copyright (c) 1999 The OpenSSL Project. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 *
19 * 3. All advertising materials mentioning features or use of this
20 * software must display the following acknowledgment:
21 * "This product includes software developed by the OpenSSL Project
22 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
23 *
24 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25 * endorse or promote products derived from this software without
26 * prior written permission. For written permission, please contact
27 * licensing@OpenSSL.org.
28 *
29 * 5. Products derived from this software may not be called "OpenSSL"
30 * nor may "OpenSSL" appear in their names without prior written
31 * permission of the OpenSSL Project.
32 *
33 * 6. Redistributions of any form whatsoever must retain the following
34 * acknowledgment:
35 * "This product includes software developed by the OpenSSL Project
36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
37 *
38 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
42 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49 * OF THE POSSIBILITY OF SUCH DAMAGE.
50 * ====================================================================
51 *
52 * This product includes cryptographic software written by Eric Young
53 * (eay@cryptsoft.com). This product includes software written by Tim
54 * Hudson (tjh@cryptsoft.com). */
55
56#include <openssl/pkcs8.h>
57
58#include <assert.h>
59#include <limits.h>
60#include <string.h>
61
62#include <openssl/bytestring.h>
63#include <openssl/cipher.h>
64#include <openssl/digest.h>
65#include <openssl/err.h>
66#include <openssl/mem.h>
67#include <openssl/nid.h>
68#include <openssl/rand.h>
69
70#include "internal.h"
71#include "../bytestring/internal.h"
72#include "../internal.h"
73
74
75static int pkcs12_encode_password(const char *in, size_t in_len, uint8_t **out,
76 size_t *out_len) {
77 CBB cbb;
78 if (!CBB_init(&cbb, in_len * 2)) {
79 OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
80 return 0;
81 }
82
83 // Convert the password to BMPString, or UCS-2. See
84 // https://tools.ietf.org/html/rfc7292#appendix-B.1.
85 CBS cbs;
86 CBS_init(&cbs, (const uint8_t *)in, in_len);
87 while (CBS_len(&cbs) != 0) {
88 uint32_t c;
89 if (!cbs_get_utf8(&cbs, &c) ||
90 !cbb_add_ucs2_be(&cbb, c)) {
91 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_INVALID_CHARACTERS);
92 goto err;
93 }
94 }
95
96 // Terminate the result with a UCS-2 NUL.
97 if (!cbb_add_ucs2_be(&cbb, 0) ||
98 !CBB_finish(&cbb, out, out_len)) {
99 goto err;
100 }
101
102 return 1;
103
104err:
105 CBB_cleanup(&cbb);
106 return 0;
107}
108
109int pkcs12_key_gen(const char *pass, size_t pass_len, const uint8_t *salt,
110 size_t salt_len, uint8_t id, unsigned iterations,
111 size_t out_len, uint8_t *out, const EVP_MD *md) {
112 // See https://tools.ietf.org/html/rfc7292#appendix-B. Quoted parts of the
113 // specification have errata applied and other typos fixed.
114
115 if (iterations < 1) {
116 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_ITERATION_COUNT);
117 return 0;
118 }
119
120 int ret = 0;
121 EVP_MD_CTX ctx;
122 EVP_MD_CTX_init(&ctx);
123 uint8_t *pass_raw = NULL, *I = NULL;
124 size_t pass_raw_len = 0, I_len = 0;
125 // If |pass| is NULL, we use the empty string rather than {0, 0} as the raw
126 // password.
127 if (pass != NULL &&
128 !pkcs12_encode_password(pass, pass_len, &pass_raw, &pass_raw_len)) {
129 goto err;
130 }
131
132 // In the spec, |block_size| is called "v", but measured in bits.
133 size_t block_size = EVP_MD_block_size(md);
134
135 // 1. Construct a string, D (the "diversifier"), by concatenating v/8 copies
136 // of ID.
137 uint8_t D[EVP_MAX_MD_BLOCK_SIZE];
138 OPENSSL_memset(D, id, block_size);
139
140 // 2. Concatenate copies of the salt together to create a string S of length
141 // v(ceiling(s/v)) bits (the final copy of the salt may be truncated to
142 // create S). Note that if the salt is the empty string, then so is S.
143 //
144 // 3. Concatenate copies of the password together to create a string P of
145 // length v(ceiling(p/v)) bits (the final copy of the password may be
146 // truncated to create P). Note that if the password is the empty string,
147 // then so is P.
148 //
149 // 4. Set I=S||P to be the concatenation of S and P.
150 if (salt_len + block_size - 1 < salt_len ||
151 pass_raw_len + block_size - 1 < pass_raw_len) {
152 OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
153 goto err;
154 }
155 size_t S_len = block_size * ((salt_len + block_size - 1) / block_size);
156 size_t P_len = block_size * ((pass_raw_len + block_size - 1) / block_size);
157 I_len = S_len + P_len;
158 if (I_len < S_len) {
159 OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
160 goto err;
161 }
162
163 I = OPENSSL_malloc(I_len);
164 if (I_len != 0 && I == NULL) {
165 OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
166 goto err;
167 }
168
169 for (size_t i = 0; i < S_len; i++) {
170 I[i] = salt[i % salt_len];
171 }
172 for (size_t i = 0; i < P_len; i++) {
173 I[i + S_len] = pass_raw[i % pass_raw_len];
174 }
175
176 while (out_len != 0) {
177 // A. Set A_i=H^r(D||I). (i.e., the r-th hash of D||I,
178 // H(H(H(... H(D||I))))
179 uint8_t A[EVP_MAX_MD_SIZE];
180 unsigned A_len;
181 if (!EVP_DigestInit_ex(&ctx, md, NULL) ||
182 !EVP_DigestUpdate(&ctx, D, block_size) ||
183 !EVP_DigestUpdate(&ctx, I, I_len) ||
184 !EVP_DigestFinal_ex(&ctx, A, &A_len)) {
185 goto err;
186 }
187 for (unsigned iter = 1; iter < iterations; iter++) {
188 if (!EVP_DigestInit_ex(&ctx, md, NULL) ||
189 !EVP_DigestUpdate(&ctx, A, A_len) ||
190 !EVP_DigestFinal_ex(&ctx, A, &A_len)) {
191 goto err;
192 }
193 }
194
195 size_t todo = out_len < A_len ? out_len : A_len;
196 OPENSSL_memcpy(out, A, todo);
197 out += todo;
198 out_len -= todo;
199 if (out_len == 0) {
200 break;
201 }
202
203 // B. Concatenate copies of A_i to create a string B of length v bits (the
204 // final copy of A_i may be truncated to create B).
205 uint8_t B[EVP_MAX_MD_BLOCK_SIZE];
206 for (size_t i = 0; i < block_size; i++) {
207 B[i] = A[i % A_len];
208 }
209
210 // C. Treating I as a concatenation I_0, I_1, ..., I_(k-1) of v-bit blocks,
211 // where k=ceiling(s/v)+ceiling(p/v), modify I by setting I_j=(I_j+B+1) mod
212 // 2^v for each j.
213 assert(I_len % block_size == 0);
214 for (size_t i = 0; i < I_len; i += block_size) {
215 unsigned carry = 1;
216 for (size_t j = block_size - 1; j < block_size; j--) {
217 carry += I[i + j] + B[j];
218 I[i + j] = (uint8_t)carry;
219 carry >>= 8;
220 }
221 }
222 }
223
224 ret = 1;
225
226err:
227 OPENSSL_free(I);
228 OPENSSL_free(pass_raw);
229 EVP_MD_CTX_cleanup(&ctx);
230 return ret;
231}
232
233static int pkcs12_pbe_cipher_init(const struct pbe_suite *suite,
234 EVP_CIPHER_CTX *ctx, unsigned iterations,
235 const char *pass, size_t pass_len,
236 const uint8_t *salt, size_t salt_len,
237 int is_encrypt) {
238 const EVP_CIPHER *cipher = suite->cipher_func();
239 const EVP_MD *md = suite->md_func();
240
241 uint8_t key[EVP_MAX_KEY_LENGTH];
242 uint8_t iv[EVP_MAX_IV_LENGTH];
243 if (!pkcs12_key_gen(pass, pass_len, salt, salt_len, PKCS12_KEY_ID, iterations,
244 EVP_CIPHER_key_length(cipher), key, md) ||
245 !pkcs12_key_gen(pass, pass_len, salt, salt_len, PKCS12_IV_ID, iterations,
246 EVP_CIPHER_iv_length(cipher), iv, md)) {
247 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEY_GEN_ERROR);
248 return 0;
249 }
250
251 int ret = EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, is_encrypt);
252 OPENSSL_cleanse(key, EVP_MAX_KEY_LENGTH);
253 OPENSSL_cleanse(iv, EVP_MAX_IV_LENGTH);
254 return ret;
255}
256
257static int pkcs12_pbe_decrypt_init(const struct pbe_suite *suite,
258 EVP_CIPHER_CTX *ctx, const char *pass,
259 size_t pass_len, CBS *param) {
260 CBS pbe_param, salt;
261 uint64_t iterations;
262 if (!CBS_get_asn1(param, &pbe_param, CBS_ASN1_SEQUENCE) ||
263 !CBS_get_asn1(&pbe_param, &salt, CBS_ASN1_OCTETSTRING) ||
264 !CBS_get_asn1_uint64(&pbe_param, &iterations) ||
265 CBS_len(&pbe_param) != 0 ||
266 CBS_len(param) != 0) {
267 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
268 return 0;
269 }
270
271 if (!pkcs12_iterations_acceptable(iterations)) {
272 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_BAD_ITERATION_COUNT);
273 return 0;
274 }
275
276 return pkcs12_pbe_cipher_init(suite, ctx, (unsigned)iterations, pass,
277 pass_len, CBS_data(&salt), CBS_len(&salt),
278 0 /* decrypt */);
279}
280
281static const struct pbe_suite kBuiltinPBE[] = {
282 {
283 NID_pbe_WithSHA1And40BitRC2_CBC,
284 // 1.2.840.113549.1.12.1.6
285 {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x06},
286 10,
287 EVP_rc2_40_cbc,
288 EVP_sha1,
289 pkcs12_pbe_decrypt_init,
290 },
291 {
292 NID_pbe_WithSHA1And128BitRC4,
293 // 1.2.840.113549.1.12.1.1
294 {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x01},
295 10,
296 EVP_rc4,
297 EVP_sha1,
298 pkcs12_pbe_decrypt_init,
299 },
300 {
301 NID_pbe_WithSHA1And3_Key_TripleDES_CBC,
302 // 1.2.840.113549.1.12.1.3
303 {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x0c, 0x01, 0x03},
304 10,
305 EVP_des_ede3_cbc,
306 EVP_sha1,
307 pkcs12_pbe_decrypt_init,
308 },
309 {
310 NID_pbes2,
311 // 1.2.840.113549.1.5.13
312 {0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x05, 0x0d},
313 9,
314 NULL,
315 NULL,
316 PKCS5_pbe2_decrypt_init,
317 },
318};
319
320static const struct pbe_suite *get_pkcs12_pbe_suite(int pbe_nid) {
321 for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(kBuiltinPBE); i++) {
322 if (kBuiltinPBE[i].pbe_nid == pbe_nid &&
323 // If |cipher_func| or |md_func| are missing, this is a PBES2 scheme.
324 kBuiltinPBE[i].cipher_func != NULL &&
325 kBuiltinPBE[i].md_func != NULL) {
326 return &kBuiltinPBE[i];
327 }
328 }
329
330 return NULL;
331}
332
333int pkcs12_pbe_encrypt_init(CBB *out, EVP_CIPHER_CTX *ctx, int alg,
334 unsigned iterations, const char *pass,
335 size_t pass_len, const uint8_t *salt,
336 size_t salt_len) {
337 const struct pbe_suite *suite = get_pkcs12_pbe_suite(alg);
338 if (suite == NULL) {
339 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_ALGORITHM);
340 return 0;
341 }
342
343 // See RFC 2898, appendix A.3.
344 CBB algorithm, oid, param, salt_cbb;
345 if (!CBB_add_asn1(out, &algorithm, CBS_ASN1_SEQUENCE) ||
346 !CBB_add_asn1(&algorithm, &oid, CBS_ASN1_OBJECT) ||
347 !CBB_add_bytes(&oid, suite->oid, suite->oid_len) ||
348 !CBB_add_asn1(&algorithm, &param, CBS_ASN1_SEQUENCE) ||
349 !CBB_add_asn1(&param, &salt_cbb, CBS_ASN1_OCTETSTRING) ||
350 !CBB_add_bytes(&salt_cbb, salt, salt_len) ||
351 !CBB_add_asn1_uint64(&param, iterations) ||
352 !CBB_flush(out)) {
353 return 0;
354 }
355
356 return pkcs12_pbe_cipher_init(suite, ctx, iterations, pass, pass_len, salt,
357 salt_len, 1 /* encrypt */);
358}
359
360int pkcs8_pbe_decrypt(uint8_t **out, size_t *out_len, CBS *algorithm,
361 const char *pass, size_t pass_len, const uint8_t *in,
362 size_t in_len) {
363 int ret = 0;
364 uint8_t *buf = NULL;;
365 EVP_CIPHER_CTX ctx;
366 EVP_CIPHER_CTX_init(&ctx);
367
368 CBS obj;
369 if (!CBS_get_asn1(algorithm, &obj, CBS_ASN1_OBJECT)) {
370 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
371 goto err;
372 }
373
374 const struct pbe_suite *suite = NULL;
375 for (unsigned i = 0; i < OPENSSL_ARRAY_SIZE(kBuiltinPBE); i++) {
376 if (CBS_mem_equal(&obj, kBuiltinPBE[i].oid, kBuiltinPBE[i].oid_len)) {
377 suite = &kBuiltinPBE[i];
378 break;
379 }
380 }
381 if (suite == NULL) {
382 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_UNKNOWN_ALGORITHM);
383 goto err;
384 }
385
386 if (!suite->decrypt_init(suite, &ctx, pass, pass_len, algorithm)) {
387 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_KEYGEN_FAILURE);
388 goto err;
389 }
390
391 buf = OPENSSL_malloc(in_len);
392 if (buf == NULL) {
393 OPENSSL_PUT_ERROR(PKCS8, ERR_R_MALLOC_FAILURE);
394 goto err;
395 }
396
397 if (in_len > INT_MAX) {
398 OPENSSL_PUT_ERROR(PKCS8, ERR_R_OVERFLOW);
399 goto err;
400 }
401
402 int n1, n2;
403 if (!EVP_DecryptUpdate(&ctx, buf, &n1, in, (int)in_len) ||
404 !EVP_DecryptFinal_ex(&ctx, buf + n1, &n2)) {
405 goto err;
406 }
407
408 *out = buf;
409 *out_len = n1 + n2;
410 ret = 1;
411 buf = NULL;
412
413err:
414 OPENSSL_free(buf);
415 EVP_CIPHER_CTX_cleanup(&ctx);
416 return ret;
417}
418
419EVP_PKEY *PKCS8_parse_encrypted_private_key(CBS *cbs, const char *pass,
420 size_t pass_len) {
421 // See RFC 5208, section 6.
422 CBS epki, algorithm, ciphertext;
423 if (!CBS_get_asn1(cbs, &epki, CBS_ASN1_SEQUENCE) ||
424 !CBS_get_asn1(&epki, &algorithm, CBS_ASN1_SEQUENCE) ||
425 !CBS_get_asn1(&epki, &ciphertext, CBS_ASN1_OCTETSTRING) ||
426 CBS_len(&epki) != 0) {
427 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_DECODE_ERROR);
428 return 0;
429 }
430
431 uint8_t *out;
432 size_t out_len;
433 if (!pkcs8_pbe_decrypt(&out, &out_len, &algorithm, pass, pass_len,
434 CBS_data(&ciphertext), CBS_len(&ciphertext))) {
435 return 0;
436 }
437
438 CBS pki;
439 CBS_init(&pki, out, out_len);
440 EVP_PKEY *ret = EVP_parse_private_key(&pki);
441 OPENSSL_free(out);
442 return ret;
443}
444
445int PKCS8_marshal_encrypted_private_key(CBB *out, int pbe_nid,
446 const EVP_CIPHER *cipher,
447 const char *pass, size_t pass_len,
448 const uint8_t *salt, size_t salt_len,
449 int iterations, const EVP_PKEY *pkey) {
450 int ret = 0;
451 uint8_t *plaintext = NULL, *salt_buf = NULL;
452 size_t plaintext_len = 0;
453 EVP_CIPHER_CTX ctx;
454 EVP_CIPHER_CTX_init(&ctx);
455
456 // Generate a random salt if necessary.
457 if (salt == NULL) {
458 if (salt_len == 0) {
459 salt_len = PKCS5_SALT_LEN;
460 }
461
462 salt_buf = OPENSSL_malloc(salt_len);
463 if (salt_buf == NULL ||
464 !RAND_bytes(salt_buf, salt_len)) {
465 goto err;
466 }
467
468 salt = salt_buf;
469 }
470
471 if (iterations <= 0) {
472 iterations = PKCS5_DEFAULT_ITERATIONS;
473 }
474
475 // Serialize the input key.
476 CBB plaintext_cbb;
477 if (!CBB_init(&plaintext_cbb, 128) ||
478 !EVP_marshal_private_key(&plaintext_cbb, pkey) ||
479 !CBB_finish(&plaintext_cbb, &plaintext, &plaintext_len)) {
480 CBB_cleanup(&plaintext_cbb);
481 goto err;
482 }
483
484 CBB epki;
485 if (!CBB_add_asn1(out, &epki, CBS_ASN1_SEQUENCE)) {
486 goto err;
487 }
488
489 // TODO(davidben): OpenSSL has since extended |pbe_nid| to control either the
490 // PBES1 scheme or the PBES2 PRF. E.g. passing |NID_hmacWithSHA256| will
491 // select PBES2 with HMAC-SHA256 as the PRF. Implement this if anything uses
492 // it. See 5693a30813a031d3921a016a870420e7eb93ec90 in OpenSSL.
493 int alg_ok;
494 if (pbe_nid == -1) {
495 alg_ok = PKCS5_pbe2_encrypt_init(&epki, &ctx, cipher, (unsigned)iterations,
496 pass, pass_len, salt, salt_len);
497 } else {
498 alg_ok = pkcs12_pbe_encrypt_init(&epki, &ctx, pbe_nid, (unsigned)iterations,
499 pass, pass_len, salt, salt_len);
500 }
501 if (!alg_ok) {
502 goto err;
503 }
504
505 size_t max_out = plaintext_len + EVP_CIPHER_CTX_block_size(&ctx);
506 if (max_out < plaintext_len) {
507 OPENSSL_PUT_ERROR(PKCS8, PKCS8_R_TOO_LONG);
508 goto err;
509 }
510
511 CBB ciphertext;
512 uint8_t *ptr;
513 int n1, n2;
514 if (!CBB_add_asn1(&epki, &ciphertext, CBS_ASN1_OCTETSTRING) ||
515 !CBB_reserve(&ciphertext, &ptr, max_out) ||
516 !EVP_CipherUpdate(&ctx, ptr, &n1, plaintext, plaintext_len) ||
517 !EVP_CipherFinal_ex(&ctx, ptr + n1, &n2) ||
518 !CBB_did_write(&ciphertext, n1 + n2) ||
519 !CBB_flush(out)) {
520 goto err;
521 }
522
523 ret = 1;
524
525err:
526 OPENSSL_free(plaintext);
527 OPENSSL_free(salt_buf);
528 EVP_CIPHER_CTX_cleanup(&ctx);
529 return ret;
530}
531