xref: /third_party/mbedtls/library/pkcs12.c (revision a8e1175b)
1/*
2 *  PKCS#12 Personal Information Exchange Syntax
3 *
4 *  Copyright The Mbed TLS Contributors
5 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7/*
8 *  The PKCS #12 Personal Information Exchange Syntax Standard v1.1
9 *
10 *  http://www.rsa.com/rsalabs/pkcs/files/h11301-wp-pkcs-12v1-1-personal-information-exchange-syntax.pdf
11 *  ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1-1.asn
12 */
13
14#include "common.h"
15
16#if defined(MBEDTLS_PKCS12_C)
17
18#include "mbedtls/pkcs12.h"
19#include "mbedtls/asn1.h"
20#if defined(MBEDTLS_CIPHER_C)
21#include "mbedtls/cipher.h"
22#endif /* MBEDTLS_CIPHER_C */
23#include "mbedtls/platform_util.h"
24#include "mbedtls/error.h"
25
26#include <string.h>
27
28#if defined(MBEDTLS_DES_C)
29#include "mbedtls/des.h"
30#endif
31
32#include "psa_util_internal.h"
33
34#if defined(MBEDTLS_ASN1_PARSE_C) && defined(MBEDTLS_CIPHER_C)
35
36static int pkcs12_parse_pbe_params(mbedtls_asn1_buf *params,
37                                   mbedtls_asn1_buf *salt, int *iterations)
38{
39    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
40    unsigned char **p = &params->p;
41    const unsigned char *end = params->p + params->len;
42
43    /*
44     *  pkcs-12PbeParams ::= SEQUENCE {
45     *    salt          OCTET STRING,
46     *    iterations    INTEGER
47     *  }
48     *
49     */
50    if (params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
51        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT,
52                                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
53    }
54
55    if ((ret = mbedtls_asn1_get_tag(p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
56        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret);
57    }
58
59    salt->p = *p;
60    *p += salt->len;
61
62    if ((ret = mbedtls_asn1_get_int(p, end, iterations)) != 0) {
63        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret);
64    }
65
66    if (*p != end) {
67        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT,
68                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
69    }
70
71    return 0;
72}
73
74#define PKCS12_MAX_PWDLEN 128
75
76static int pkcs12_pbe_derive_key_iv(mbedtls_asn1_buf *pbe_params, mbedtls_md_type_t md_type,
77                                    const unsigned char *pwd,  size_t pwdlen,
78                                    unsigned char *key, size_t keylen,
79                                    unsigned char *iv,  size_t ivlen)
80{
81    int ret, iterations = 0;
82    mbedtls_asn1_buf salt;
83    size_t i;
84    unsigned char unipwd[PKCS12_MAX_PWDLEN * 2 + 2];
85
86    if (pwdlen > PKCS12_MAX_PWDLEN) {
87        return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
88    }
89
90    memset(&salt, 0, sizeof(mbedtls_asn1_buf));
91    memset(&unipwd, 0, sizeof(unipwd));
92
93    if ((ret = pkcs12_parse_pbe_params(pbe_params, &salt,
94                                       &iterations)) != 0) {
95        return ret;
96    }
97
98    for (i = 0; i < pwdlen; i++) {
99        unipwd[i * 2 + 1] = pwd[i];
100    }
101
102    if ((ret = mbedtls_pkcs12_derivation(key, keylen, unipwd, pwdlen * 2 + 2,
103                                         salt.p, salt.len, md_type,
104                                         MBEDTLS_PKCS12_DERIVE_KEY, iterations)) != 0) {
105        return ret;
106    }
107
108    if (iv == NULL || ivlen == 0) {
109        return 0;
110    }
111
112    if ((ret = mbedtls_pkcs12_derivation(iv, ivlen, unipwd, pwdlen * 2 + 2,
113                                         salt.p, salt.len, md_type,
114                                         MBEDTLS_PKCS12_DERIVE_IV, iterations)) != 0) {
115        return ret;
116    }
117    return 0;
118}
119
120#undef PKCS12_MAX_PWDLEN
121
122#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
123int mbedtls_pkcs12_pbe_ext(mbedtls_asn1_buf *pbe_params, int mode,
124                           mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
125                           const unsigned char *pwd,  size_t pwdlen,
126                           const unsigned char *data, size_t len,
127                           unsigned char *output, size_t output_size,
128                           size_t *output_len);
129#endif
130
131#if !defined(MBEDTLS_DEPRECATED_REMOVED)
132int mbedtls_pkcs12_pbe(mbedtls_asn1_buf *pbe_params, int mode,
133                       mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
134                       const unsigned char *pwd,  size_t pwdlen,
135                       const unsigned char *data, size_t len,
136                       unsigned char *output)
137{
138    size_t output_len = 0;
139
140    /* We assume caller of the function is providing a big enough output buffer
141     * so we pass output_size as SIZE_MAX to pass checks, However, no guarantees
142     * for the output size actually being correct.
143     */
144    return mbedtls_pkcs12_pbe_ext(pbe_params, mode, cipher_type, md_type,
145                                  pwd, pwdlen, data, len, output, SIZE_MAX,
146                                  &output_len);
147}
148#endif
149
150int mbedtls_pkcs12_pbe_ext(mbedtls_asn1_buf *pbe_params, int mode,
151                           mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
152                           const unsigned char *pwd,  size_t pwdlen,
153                           const unsigned char *data, size_t len,
154                           unsigned char *output, size_t output_size,
155                           size_t *output_len)
156{
157    int ret, keylen = 0;
158    unsigned char key[32];
159    unsigned char iv[16];
160    const mbedtls_cipher_info_t *cipher_info;
161    mbedtls_cipher_context_t cipher_ctx;
162    size_t iv_len = 0;
163    size_t finish_olen = 0;
164    unsigned int padlen = 0;
165
166    if (pwd == NULL && pwdlen != 0) {
167        return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
168    }
169
170    cipher_info = mbedtls_cipher_info_from_type(cipher_type);
171    if (cipher_info == NULL) {
172        return MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE;
173    }
174
175    keylen = (int) mbedtls_cipher_info_get_key_bitlen(cipher_info) / 8;
176
177    if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
178        if (output_size < len) {
179            return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
180        }
181    }
182
183    if (mode == MBEDTLS_PKCS12_PBE_ENCRYPT) {
184        padlen = cipher_info->block_size - (len % cipher_info->block_size);
185        if (output_size < (len + padlen)) {
186            return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
187        }
188    }
189
190    iv_len = mbedtls_cipher_info_get_iv_size(cipher_info);
191    if ((ret = pkcs12_pbe_derive_key_iv(pbe_params, md_type, pwd, pwdlen,
192                                        key, keylen,
193                                        iv, iv_len)) != 0) {
194        return ret;
195    }
196
197    mbedtls_cipher_init(&cipher_ctx);
198
199    if ((ret = mbedtls_cipher_setup(&cipher_ctx, cipher_info)) != 0) {
200        goto exit;
201    }
202
203    if ((ret = mbedtls_cipher_setkey(&cipher_ctx, key, 8 * keylen,
204                                     (mbedtls_operation_t) mode)) != 0) {
205        goto exit;
206    }
207
208#if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
209    {
210        /* PKCS12 uses CBC with PKCS7 padding */
211        mbedtls_cipher_padding_t padding = MBEDTLS_PADDING_PKCS7;
212#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
213        /* For historical reasons, when decrypting, this function works when
214         * decrypting even when support for PKCS7 padding is disabled. In this
215         * case, it ignores the padding, and so will never report a
216         * password mismatch.
217         */
218        if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
219            padding = MBEDTLS_PADDING_NONE;
220        }
221#endif
222        if ((ret = mbedtls_cipher_set_padding_mode(&cipher_ctx, padding)) != 0) {
223            goto exit;
224        }
225    }
226#endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */
227
228    ret = mbedtls_cipher_crypt(&cipher_ctx, iv, iv_len, data, len, output, &finish_olen);
229    if (ret == MBEDTLS_ERR_CIPHER_INVALID_PADDING) {
230        ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;
231    }
232
233    *output_len += finish_olen;
234
235exit:
236    mbedtls_platform_zeroize(key, sizeof(key));
237    mbedtls_platform_zeroize(iv,  sizeof(iv));
238    mbedtls_cipher_free(&cipher_ctx);
239
240    return ret;
241}
242
243#endif /* MBEDTLS_ASN1_PARSE_C && MBEDTLS_CIPHER_C */
244
245static void pkcs12_fill_buffer(unsigned char *data, size_t data_len,
246                               const unsigned char *filler, size_t fill_len)
247{
248    unsigned char *p = data;
249    size_t use_len;
250
251    if (filler != NULL && fill_len != 0) {
252        while (data_len > 0) {
253            use_len = (data_len > fill_len) ? fill_len : data_len;
254            memcpy(p, filler, use_len);
255            p += use_len;
256            data_len -= use_len;
257        }
258    } else {
259        /* If either of the above are not true then clearly there is nothing
260         * that this function can do. The function should *not* be called
261         * under either of those circumstances, as you could end up with an
262         * incorrect output but for safety's sake, leaving the check in as
263         * otherwise we could end up with memory corruption.*/
264    }
265}
266
267
268static int calculate_hashes(mbedtls_md_type_t md_type, int iterations,
269                            unsigned char *diversifier, unsigned char *salt_block,
270                            unsigned char *pwd_block, unsigned char *hash_output, int use_salt,
271                            int use_password, size_t hlen, size_t v)
272{
273    int ret = -1;
274    size_t i;
275    const mbedtls_md_info_t *md_info;
276    mbedtls_md_context_t md_ctx;
277    md_info = mbedtls_md_info_from_type(md_type);
278    if (md_info == NULL) {
279        return MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE;
280    }
281
282    mbedtls_md_init(&md_ctx);
283
284    if ((ret = mbedtls_md_setup(&md_ctx, md_info, 0)) != 0) {
285        return ret;
286    }
287    // Calculate hash( diversifier || salt_block || pwd_block )
288    if ((ret = mbedtls_md_starts(&md_ctx)) != 0) {
289        goto exit;
290    }
291
292    if ((ret = mbedtls_md_update(&md_ctx, diversifier, v)) != 0) {
293        goto exit;
294    }
295
296    if (use_salt != 0) {
297        if ((ret = mbedtls_md_update(&md_ctx, salt_block, v)) != 0) {
298            goto exit;
299        }
300    }
301
302    if (use_password != 0) {
303        if ((ret = mbedtls_md_update(&md_ctx, pwd_block, v)) != 0) {
304            goto exit;
305        }
306    }
307
308    if ((ret = mbedtls_md_finish(&md_ctx, hash_output)) != 0) {
309        goto exit;
310    }
311
312    // Perform remaining ( iterations - 1 ) recursive hash calculations
313    for (i = 1; i < (size_t) iterations; i++) {
314        if ((ret = mbedtls_md(md_info, hash_output, hlen, hash_output))
315            != 0) {
316            goto exit;
317        }
318    }
319
320exit:
321    mbedtls_md_free(&md_ctx);
322    return ret;
323}
324
325
326int mbedtls_pkcs12_derivation(unsigned char *data, size_t datalen,
327                              const unsigned char *pwd, size_t pwdlen,
328                              const unsigned char *salt, size_t saltlen,
329                              mbedtls_md_type_t md_type, int id, int iterations)
330{
331    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
332    unsigned int j;
333
334    unsigned char diversifier[128];
335    unsigned char salt_block[128], pwd_block[128], hash_block[128] = { 0 };
336    unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
337    unsigned char *p;
338    unsigned char c;
339    int           use_password = 0;
340    int           use_salt = 0;
341
342    size_t hlen, use_len, v, i;
343
344    // This version only allows max of 64 bytes of password or salt
345    if (datalen > 128 || pwdlen > 64 || saltlen > 64) {
346        return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
347    }
348
349    if (pwd == NULL && pwdlen != 0) {
350        return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
351    }
352
353    if (salt == NULL && saltlen != 0) {
354        return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
355    }
356
357    use_password = (pwd && pwdlen != 0);
358    use_salt = (salt && saltlen != 0);
359
360    hlen = mbedtls_md_get_size_from_type(md_type);
361
362    if (hlen <= 32) {
363        v = 64;
364    } else {
365        v = 128;
366    }
367
368    memset(diversifier, (unsigned char) id, v);
369
370    if (use_salt != 0) {
371        pkcs12_fill_buffer(salt_block, v, salt, saltlen);
372    }
373
374    if (use_password != 0) {
375        pkcs12_fill_buffer(pwd_block,  v, pwd,  pwdlen);
376    }
377
378    p = data;
379    while (datalen > 0) {
380        if (calculate_hashes(md_type, iterations, diversifier, salt_block,
381                             pwd_block, hash_output, use_salt, use_password, hlen,
382                             v) != 0) {
383            goto exit;
384        }
385
386        use_len = (datalen > hlen) ? hlen : datalen;
387        memcpy(p, hash_output, use_len);
388        datalen -= use_len;
389        p += use_len;
390
391        if (datalen == 0) {
392            break;
393        }
394
395        // Concatenating copies of hash_output into hash_block (B)
396        pkcs12_fill_buffer(hash_block, v, hash_output, hlen);
397
398        // B += 1
399        for (i = v; i > 0; i--) {
400            if (++hash_block[i - 1] != 0) {
401                break;
402            }
403        }
404
405        if (use_salt != 0) {
406            // salt_block += B
407            c = 0;
408            for (i = v; i > 0; i--) {
409                j = salt_block[i - 1] + hash_block[i - 1] + c;
410                c = MBEDTLS_BYTE_1(j);
411                salt_block[i - 1] = MBEDTLS_BYTE_0(j);
412            }
413        }
414
415        if (use_password != 0) {
416            // pwd_block  += B
417            c = 0;
418            for (i = v; i > 0; i--) {
419                j = pwd_block[i - 1] + hash_block[i - 1] + c;
420                c = MBEDTLS_BYTE_1(j);
421                pwd_block[i - 1] = MBEDTLS_BYTE_0(j);
422            }
423        }
424    }
425
426    ret = 0;
427
428exit:
429    mbedtls_platform_zeroize(salt_block, sizeof(salt_block));
430    mbedtls_platform_zeroize(pwd_block, sizeof(pwd_block));
431    mbedtls_platform_zeroize(hash_block, sizeof(hash_block));
432    mbedtls_platform_zeroize(hash_output, sizeof(hash_output));
433
434    return ret;
435}
436
437#endif /* MBEDTLS_PKCS12_C */
438