xref: /optee_os/lib/libmbedtls/mbedtls/library/cipher.c (revision 19116a65b6728f04be40b827236dce7a34da49e1)
1 /**
2  * \file cipher.c
3  *
4  * \brief Generic cipher wrapper for Mbed TLS
5  *
6  * \author Adriaan de Jong <dejong@fox-it.com>
7  *
8  *  Copyright The Mbed TLS Contributors
9  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
10  */
11 
12 #include "common.h"
13 
14 #if defined(MBEDTLS_CIPHER_C)
15 
16 #include "mbedtls/cipher.h"
17 #include "cipher_invasive.h"
18 #include "cipher_wrap.h"
19 #include "mbedtls/platform_util.h"
20 #include "mbedtls/error.h"
21 #include "mbedtls/constant_time.h"
22 #include "constant_time_internal.h"
23 
24 #include <stdlib.h>
25 #include <string.h>
26 
27 #if defined(MBEDTLS_CHACHAPOLY_C)
28 #include "mbedtls/chachapoly.h"
29 #endif
30 
31 #if defined(MBEDTLS_GCM_C)
32 #include "mbedtls/gcm.h"
33 #endif
34 
35 #if defined(MBEDTLS_CCM_C)
36 #include "mbedtls/ccm.h"
37 #endif
38 
39 #if defined(MBEDTLS_CHACHA20_C)
40 #include "mbedtls/chacha20.h"
41 #endif
42 
43 #if defined(MBEDTLS_CMAC_C)
44 #include "mbedtls/cmac.h"
45 #endif
46 
47 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
48 #include "psa/crypto.h"
49 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
50 
51 #if defined(MBEDTLS_NIST_KW_C)
52 #include "mbedtls/nist_kw.h"
53 #endif
54 
55 #include "mbedtls/platform.h"
56 
57 static int supported_init = 0;
58 
mbedtls_cipher_get_base(const mbedtls_cipher_info_t * info)59 static inline const mbedtls_cipher_base_t *mbedtls_cipher_get_base(
60     const mbedtls_cipher_info_t *info)
61 {
62     return mbedtls_cipher_base_lookup_table[info->base_idx];
63 }
64 
mbedtls_cipher_list(void)65 const int *mbedtls_cipher_list(void)
66 {
67     const mbedtls_cipher_definition_t *def;
68     int *type;
69 
70     if (!supported_init) {
71         def = mbedtls_cipher_definitions;
72         type = mbedtls_cipher_supported;
73 
74         while (def->type != 0) {
75             *type++ = (*def++).type;
76         }
77 
78         *type = 0;
79 
80         supported_init = 1;
81     }
82 
83     return mbedtls_cipher_supported;
84 }
85 
mbedtls_cipher_info_from_type(const mbedtls_cipher_type_t cipher_type)86 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_type(
87     const mbedtls_cipher_type_t cipher_type)
88 {
89     const mbedtls_cipher_definition_t *def;
90 
91     for (def = mbedtls_cipher_definitions; def->info != NULL; def++) {
92         if (def->type == cipher_type) {
93             return def->info;
94         }
95     }
96 
97     return NULL;
98 }
99 
mbedtls_cipher_info_from_string(const char * cipher_name)100 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_string(
101     const char *cipher_name)
102 {
103     const mbedtls_cipher_definition_t *def;
104 
105     if (NULL == cipher_name) {
106         return NULL;
107     }
108 
109     for (def = mbedtls_cipher_definitions; def->info != NULL; def++) {
110         if (!strcmp(def->info->name, cipher_name)) {
111             return def->info;
112         }
113     }
114 
115     return NULL;
116 }
117 
mbedtls_cipher_info_from_values(const mbedtls_cipher_id_t cipher_id,int key_bitlen,const mbedtls_cipher_mode_t mode)118 const mbedtls_cipher_info_t *mbedtls_cipher_info_from_values(
119     const mbedtls_cipher_id_t cipher_id,
120     int key_bitlen,
121     const mbedtls_cipher_mode_t mode)
122 {
123     const mbedtls_cipher_definition_t *def;
124 
125     for (def = mbedtls_cipher_definitions; def->info != NULL; def++) {
126         if (mbedtls_cipher_get_base(def->info)->cipher == cipher_id &&
127             mbedtls_cipher_info_get_key_bitlen(def->info) == (unsigned) key_bitlen &&
128             def->info->mode == mode) {
129             return def->info;
130         }
131     }
132 
133     return NULL;
134 }
135 
136 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
mbedtls_psa_translate_cipher_type(mbedtls_cipher_type_t cipher)137 static inline psa_key_type_t mbedtls_psa_translate_cipher_type(
138     mbedtls_cipher_type_t cipher)
139 {
140     switch (cipher) {
141         case MBEDTLS_CIPHER_AES_128_CCM:
142         case MBEDTLS_CIPHER_AES_192_CCM:
143         case MBEDTLS_CIPHER_AES_256_CCM:
144         case MBEDTLS_CIPHER_AES_128_CCM_STAR_NO_TAG:
145         case MBEDTLS_CIPHER_AES_192_CCM_STAR_NO_TAG:
146         case MBEDTLS_CIPHER_AES_256_CCM_STAR_NO_TAG:
147         case MBEDTLS_CIPHER_AES_128_GCM:
148         case MBEDTLS_CIPHER_AES_192_GCM:
149         case MBEDTLS_CIPHER_AES_256_GCM:
150         case MBEDTLS_CIPHER_AES_128_CBC:
151         case MBEDTLS_CIPHER_AES_192_CBC:
152         case MBEDTLS_CIPHER_AES_256_CBC:
153         case MBEDTLS_CIPHER_AES_128_ECB:
154         case MBEDTLS_CIPHER_AES_192_ECB:
155         case MBEDTLS_CIPHER_AES_256_ECB:
156             return PSA_KEY_TYPE_AES;
157 
158         /* ARIA not yet supported in PSA. */
159         /* case MBEDTLS_CIPHER_ARIA_128_CCM:
160            case MBEDTLS_CIPHER_ARIA_192_CCM:
161            case MBEDTLS_CIPHER_ARIA_256_CCM:
162            case MBEDTLS_CIPHER_ARIA_128_CCM_STAR_NO_TAG:
163            case MBEDTLS_CIPHER_ARIA_192_CCM_STAR_NO_TAG:
164            case MBEDTLS_CIPHER_ARIA_256_CCM_STAR_NO_TAG:
165            case MBEDTLS_CIPHER_ARIA_128_GCM:
166            case MBEDTLS_CIPHER_ARIA_192_GCM:
167            case MBEDTLS_CIPHER_ARIA_256_GCM:
168            case MBEDTLS_CIPHER_ARIA_128_CBC:
169            case MBEDTLS_CIPHER_ARIA_192_CBC:
170            case MBEDTLS_CIPHER_ARIA_256_CBC:
171                return( PSA_KEY_TYPE_ARIA ); */
172 
173         default:
174             return 0;
175     }
176 }
177 
mbedtls_psa_translate_cipher_mode(mbedtls_cipher_mode_t mode,size_t taglen)178 static inline psa_algorithm_t mbedtls_psa_translate_cipher_mode(
179     mbedtls_cipher_mode_t mode, size_t taglen)
180 {
181     switch (mode) {
182         case MBEDTLS_MODE_ECB:
183             return PSA_ALG_ECB_NO_PADDING;
184         case MBEDTLS_MODE_GCM:
185             return PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM, taglen);
186         case MBEDTLS_MODE_CCM:
187             return PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_CCM, taglen);
188         case MBEDTLS_MODE_CCM_STAR_NO_TAG:
189             return PSA_ALG_CCM_STAR_NO_TAG;
190         case MBEDTLS_MODE_CBC:
191             if (taglen == 0) {
192                 return PSA_ALG_CBC_NO_PADDING;
193             } else {
194                 return 0;
195             }
196         default:
197             return 0;
198     }
199 }
200 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
201 
mbedtls_cipher_init(mbedtls_cipher_context_t * ctx)202 void mbedtls_cipher_init(mbedtls_cipher_context_t *ctx)
203 {
204     memset(ctx, 0, sizeof(mbedtls_cipher_context_t));
205 }
206 
mbedtls_cipher_free(mbedtls_cipher_context_t * ctx)207 void mbedtls_cipher_free(mbedtls_cipher_context_t *ctx)
208 {
209     if (ctx == NULL) {
210         return;
211     }
212 
213 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
214     if (ctx->psa_enabled == 1) {
215         if (ctx->cipher_ctx != NULL) {
216             mbedtls_cipher_context_psa * const cipher_psa =
217                 (mbedtls_cipher_context_psa *) ctx->cipher_ctx;
218 
219             if (cipher_psa->slot_state == MBEDTLS_CIPHER_PSA_KEY_OWNED) {
220                 /* xxx_free() doesn't allow to return failures. */
221                 (void) psa_destroy_key(cipher_psa->slot);
222             }
223 
224             mbedtls_zeroize_and_free(cipher_psa, sizeof(*cipher_psa));
225         }
226 
227         mbedtls_platform_zeroize(ctx, sizeof(mbedtls_cipher_context_t));
228         return;
229     }
230 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
231 
232 #if defined(MBEDTLS_CMAC_C)
233     if (ctx->cmac_ctx) {
234         mbedtls_zeroize_and_free(ctx->cmac_ctx,
235                                  sizeof(mbedtls_cmac_context_t));
236     }
237 #endif
238 
239     if (ctx->cipher_ctx) {
240         mbedtls_cipher_get_base(ctx->cipher_info)->ctx_free_func(ctx->cipher_ctx);
241     }
242 
243     mbedtls_platform_zeroize(ctx, sizeof(mbedtls_cipher_context_t));
244 }
245 
mbedtls_cipher_clone(mbedtls_cipher_context_t * dst,const mbedtls_cipher_context_t * src)246 int mbedtls_cipher_clone(mbedtls_cipher_context_t *dst,
247                          const mbedtls_cipher_context_t *src)
248 {
249     if (dst == NULL || dst->cipher_info == NULL ||
250         src == NULL || src->cipher_info == NULL) {
251         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
252     }
253 
254     dst->cipher_info = src->cipher_info;
255     dst->key_bitlen = src->key_bitlen;
256     dst->operation = src->operation;
257 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
258     dst->add_padding = src->add_padding;
259     dst->get_padding = src->get_padding;
260 #endif
261     memcpy(dst->unprocessed_data, src->unprocessed_data, MBEDTLS_MAX_BLOCK_LENGTH);
262     dst->unprocessed_len = src->unprocessed_len;
263     memcpy(dst->iv, src->iv, MBEDTLS_MAX_IV_LENGTH);
264     dst->iv_size = src->iv_size;
265     if (mbedtls_cipher_get_base(dst->cipher_info)->ctx_clone_func)
266         mbedtls_cipher_get_base(dst->cipher_info)->ctx_clone_func(dst->cipher_ctx, src->cipher_ctx);
267 
268 #if defined(MBEDTLS_CMAC_C)
269     if (dst->cmac_ctx != NULL && src->cmac_ctx != NULL)
270         memcpy(dst->cmac_ctx, src->cmac_ctx, sizeof(mbedtls_cmac_context_t));
271 #endif
272     return 0;
273 }
274 
mbedtls_cipher_setup(mbedtls_cipher_context_t * ctx,const mbedtls_cipher_info_t * cipher_info)275 int mbedtls_cipher_setup(mbedtls_cipher_context_t *ctx,
276                          const mbedtls_cipher_info_t *cipher_info)
277 {
278     if (cipher_info == NULL) {
279         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
280     }
281 
282     memset(ctx, 0, sizeof(mbedtls_cipher_context_t));
283 
284     if (mbedtls_cipher_get_base(cipher_info)->ctx_alloc_func != NULL) {
285         ctx->cipher_ctx = mbedtls_cipher_get_base(cipher_info)->ctx_alloc_func();
286         if (ctx->cipher_ctx == NULL) {
287             return MBEDTLS_ERR_CIPHER_ALLOC_FAILED;
288         }
289     }
290 
291     ctx->cipher_info = cipher_info;
292 
293     return 0;
294 }
295 
296 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
mbedtls_cipher_setup_psa(mbedtls_cipher_context_t * ctx,const mbedtls_cipher_info_t * cipher_info,size_t taglen)297 int mbedtls_cipher_setup_psa(mbedtls_cipher_context_t *ctx,
298                              const mbedtls_cipher_info_t *cipher_info,
299                              size_t taglen)
300 {
301     psa_algorithm_t alg;
302     mbedtls_cipher_context_psa *cipher_psa;
303 
304     if (NULL == cipher_info || NULL == ctx) {
305         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
306     }
307 
308     /* Check that the underlying cipher mode and cipher type are
309      * supported by the underlying PSA Crypto implementation. */
310     alg = mbedtls_psa_translate_cipher_mode(((mbedtls_cipher_mode_t) cipher_info->mode), taglen);
311     if (alg == 0) {
312         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
313     }
314     if (mbedtls_psa_translate_cipher_type(((mbedtls_cipher_type_t) cipher_info->type)) == 0) {
315         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
316     }
317 
318     memset(ctx, 0, sizeof(mbedtls_cipher_context_t));
319 
320     cipher_psa = mbedtls_calloc(1, sizeof(mbedtls_cipher_context_psa));
321     if (cipher_psa == NULL) {
322         return MBEDTLS_ERR_CIPHER_ALLOC_FAILED;
323     }
324     cipher_psa->alg  = alg;
325     ctx->cipher_ctx  = cipher_psa;
326     ctx->cipher_info = cipher_info;
327     ctx->psa_enabled = 1;
328     return 0;
329 }
330 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
331 
mbedtls_cipher_setup_info(mbedtls_cipher_context_t * ctx,const mbedtls_cipher_info_t * cipher_info)332 int mbedtls_cipher_setup_info(mbedtls_cipher_context_t *ctx,
333                               const mbedtls_cipher_info_t *cipher_info)
334 {
335     if (NULL == cipher_info || NULL == ctx)
336         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
337 
338     ctx->cipher_info = cipher_info;
339     return 0;
340 }
341 
mbedtls_cipher_setkey(mbedtls_cipher_context_t * ctx,const unsigned char * key,int key_bitlen,const mbedtls_operation_t operation)342 int mbedtls_cipher_setkey(mbedtls_cipher_context_t *ctx,
343                           const unsigned char *key,
344                           int key_bitlen,
345                           const mbedtls_operation_t operation)
346 {
347     if (operation != MBEDTLS_ENCRYPT && operation != MBEDTLS_DECRYPT) {
348         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
349     }
350     if (ctx->cipher_info == NULL) {
351         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
352     }
353 #if defined(MBEDTLS_BLOCK_CIPHER_NO_DECRYPT)
354     if (MBEDTLS_MODE_ECB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) &&
355         MBEDTLS_DECRYPT == operation) {
356         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
357     }
358 #endif
359 
360 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
361     if (ctx->psa_enabled == 1) {
362         mbedtls_cipher_context_psa * const cipher_psa =
363             (mbedtls_cipher_context_psa *) ctx->cipher_ctx;
364 
365         size_t const key_bytelen = ((size_t) key_bitlen + 7) / 8;
366 
367         psa_status_t status;
368         psa_key_type_t key_type;
369         psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
370 
371         /* PSA Crypto API only accepts byte-aligned keys. */
372         if (key_bitlen % 8 != 0) {
373             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
374         }
375 
376         /* Don't allow keys to be set multiple times. */
377         if (cipher_psa->slot_state != MBEDTLS_CIPHER_PSA_KEY_UNSET) {
378             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
379         }
380 
381         key_type = mbedtls_psa_translate_cipher_type(
382             ((mbedtls_cipher_type_t) ctx->cipher_info->type));
383         if (key_type == 0) {
384             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
385         }
386         psa_set_key_type(&attributes, key_type);
387 
388         /* Mbed TLS' cipher layer doesn't enforce the mode of operation
389          * (encrypt vs. decrypt): it is possible to setup a key for encryption
390          * and use it for AEAD decryption. Until tests relying on this
391          * are changed, allow any usage in PSA. */
392         psa_set_key_usage_flags(&attributes,
393                                 PSA_KEY_USAGE_ENCRYPT | PSA_KEY_USAGE_DECRYPT);
394         psa_set_key_algorithm(&attributes, cipher_psa->alg);
395 
396         status = psa_import_key(&attributes, key, key_bytelen,
397                                 &cipher_psa->slot);
398         switch (status) {
399             case PSA_SUCCESS:
400                 break;
401             case PSA_ERROR_INSUFFICIENT_MEMORY:
402                 return MBEDTLS_ERR_CIPHER_ALLOC_FAILED;
403             case PSA_ERROR_NOT_SUPPORTED:
404                 return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
405             default:
406                 return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
407         }
408         /* Indicate that we own the key slot and need to
409          * destroy it in mbedtls_cipher_free(). */
410         cipher_psa->slot_state = MBEDTLS_CIPHER_PSA_KEY_OWNED;
411 
412         ctx->key_bitlen = key_bitlen;
413         ctx->operation = operation;
414         return 0;
415     }
416 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
417 
418     if ((ctx->cipher_info->flags & MBEDTLS_CIPHER_VARIABLE_KEY_LEN) == 0 &&
419         (int) mbedtls_cipher_info_get_key_bitlen(ctx->cipher_info) != key_bitlen) {
420         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
421     }
422 
423     ctx->key_bitlen = key_bitlen;
424     ctx->operation = operation;
425 
426 #if !defined(MBEDTLS_BLOCK_CIPHER_NO_DECRYPT)
427     /*
428      * For OFB, CFB and CTR mode always use the encryption key schedule
429      */
430     if (MBEDTLS_ENCRYPT == operation ||
431         MBEDTLS_MODE_CFB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
432         MBEDTLS_MODE_OFB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
433         MBEDTLS_MODE_CTR == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
434         return mbedtls_cipher_get_base(ctx->cipher_info)->setkey_enc_func(ctx->cipher_ctx, key,
435                                                                           ctx->key_bitlen);
436     }
437 
438     if (MBEDTLS_DECRYPT == operation) {
439         return mbedtls_cipher_get_base(ctx->cipher_info)->setkey_dec_func(ctx->cipher_ctx, key,
440                                                                           ctx->key_bitlen);
441     }
442 #else
443     if (operation == MBEDTLS_ENCRYPT || operation == MBEDTLS_DECRYPT) {
444         return mbedtls_cipher_get_base(ctx->cipher_info)->setkey_enc_func(ctx->cipher_ctx, key,
445                                                                           ctx->key_bitlen);
446     }
447 #endif
448 
449     return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
450 }
451 
mbedtls_cipher_set_iv(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len)452 int mbedtls_cipher_set_iv(mbedtls_cipher_context_t *ctx,
453                           const unsigned char *iv,
454                           size_t iv_len)
455 {
456     size_t actual_iv_size;
457 
458     if (ctx->cipher_info == NULL) {
459         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
460     }
461 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
462     if (ctx->psa_enabled == 1) {
463         /* While PSA Crypto has an API for multipart
464          * operations, we currently don't make it
465          * accessible through the cipher layer. */
466         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
467     }
468 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
469 
470     /* avoid buffer overflow in ctx->iv */
471     if (iv_len > MBEDTLS_MAX_IV_LENGTH) {
472         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
473     }
474 
475     if ((ctx->cipher_info->flags & MBEDTLS_CIPHER_VARIABLE_IV_LEN) != 0) {
476         actual_iv_size = iv_len;
477     } else {
478         actual_iv_size = mbedtls_cipher_info_get_iv_size(ctx->cipher_info);
479 
480         /* avoid reading past the end of input buffer */
481         if (actual_iv_size > iv_len) {
482             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
483         }
484     }
485 
486 #if defined(MBEDTLS_CHACHA20_C)
487     if (((mbedtls_cipher_type_t) ctx->cipher_info->type) == MBEDTLS_CIPHER_CHACHA20) {
488         /* Even though the actual_iv_size is overwritten with a correct value
489          * of 12 from the cipher info, return an error to indicate that
490          * the input iv_len is wrong. */
491         if (iv_len != 12) {
492             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
493         }
494 
495         if (0 != mbedtls_chacha20_starts((mbedtls_chacha20_context *) ctx->cipher_ctx,
496                                          iv,
497                                          0U)) {   /* Initial counter value */
498             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
499         }
500     }
501 #if defined(MBEDTLS_CHACHAPOLY_C)
502     if (((mbedtls_cipher_type_t) ctx->cipher_info->type) == MBEDTLS_CIPHER_CHACHA20_POLY1305 &&
503         iv_len != 12) {
504         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
505     }
506 #endif
507 #endif
508 
509 #if defined(MBEDTLS_GCM_C)
510     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
511         return mbedtls_gcm_starts((mbedtls_gcm_context *) ctx->cipher_ctx,
512                                   ctx->operation,
513                                   iv, iv_len);
514     }
515 #endif
516 
517 #if defined(MBEDTLS_CCM_C)
518     if (MBEDTLS_MODE_CCM_STAR_NO_TAG == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
519         int set_lengths_result;
520         int ccm_star_mode;
521 
522         set_lengths_result = mbedtls_ccm_set_lengths(
523             (mbedtls_ccm_context *) ctx->cipher_ctx,
524             0, 0, 0);
525         if (set_lengths_result != 0) {
526             return set_lengths_result;
527         }
528 
529         if (ctx->operation == MBEDTLS_DECRYPT) {
530             ccm_star_mode = MBEDTLS_CCM_STAR_DECRYPT;
531         } else if (ctx->operation == MBEDTLS_ENCRYPT) {
532             ccm_star_mode = MBEDTLS_CCM_STAR_ENCRYPT;
533         } else {
534             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
535         }
536 
537         return mbedtls_ccm_starts((mbedtls_ccm_context *) ctx->cipher_ctx,
538                                   ccm_star_mode,
539                                   iv, iv_len);
540     }
541 #endif
542 
543     if (actual_iv_size != 0) {
544         memcpy(ctx->iv, iv, actual_iv_size);
545         ctx->iv_size = actual_iv_size;
546     }
547 
548     return 0;
549 }
550 
mbedtls_cipher_reset(mbedtls_cipher_context_t * ctx)551 int mbedtls_cipher_reset(mbedtls_cipher_context_t *ctx)
552 {
553     if (ctx->cipher_info == NULL) {
554         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
555     }
556 
557 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
558     if (ctx->psa_enabled == 1) {
559         /* We don't support resetting PSA-based
560          * cipher contexts, yet. */
561         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
562     }
563 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
564 
565     ctx->unprocessed_len = 0;
566 
567     return 0;
568 }
569 
570 #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CHACHAPOLY_C)
mbedtls_cipher_update_ad(mbedtls_cipher_context_t * ctx,const unsigned char * ad,size_t ad_len)571 int mbedtls_cipher_update_ad(mbedtls_cipher_context_t *ctx,
572                              const unsigned char *ad, size_t ad_len)
573 {
574     if (ctx->cipher_info == NULL) {
575         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
576     }
577 
578 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
579     if (ctx->psa_enabled == 1) {
580         /* While PSA Crypto has an API for multipart
581          * operations, we currently don't make it
582          * accessible through the cipher layer. */
583         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
584     }
585 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
586 
587 #if defined(MBEDTLS_GCM_C)
588     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
589         return mbedtls_gcm_update_ad((mbedtls_gcm_context *) ctx->cipher_ctx,
590                                      ad, ad_len);
591     }
592 #endif
593 
594 #if defined(MBEDTLS_CHACHAPOLY_C)
595     if (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) {
596         int result;
597         mbedtls_chachapoly_mode_t mode;
598 
599         mode = (ctx->operation == MBEDTLS_ENCRYPT)
600                 ? MBEDTLS_CHACHAPOLY_ENCRYPT
601                 : MBEDTLS_CHACHAPOLY_DECRYPT;
602 
603         result = mbedtls_chachapoly_starts((mbedtls_chachapoly_context *) ctx->cipher_ctx,
604                                            ctx->iv,
605                                            mode);
606         if (result != 0) {
607             return result;
608         }
609 
610         return mbedtls_chachapoly_update_aad((mbedtls_chachapoly_context *) ctx->cipher_ctx,
611                                              ad, ad_len);
612     }
613 #endif
614 
615     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
616 }
617 #endif /* MBEDTLS_GCM_C || MBEDTLS_CHACHAPOLY_C */
618 
mbedtls_cipher_update(mbedtls_cipher_context_t * ctx,const unsigned char * input,size_t ilen,unsigned char * output,size_t * olen)619 int mbedtls_cipher_update(mbedtls_cipher_context_t *ctx, const unsigned char *input,
620                           size_t ilen, unsigned char *output, size_t *olen)
621 {
622     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
623     size_t block_size;
624 
625     if (ctx->cipher_info == NULL) {
626         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
627     }
628 
629 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
630     if (ctx->psa_enabled == 1) {
631         /* While PSA Crypto has an API for multipart
632          * operations, we currently don't make it
633          * accessible through the cipher layer. */
634         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
635     }
636 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
637 
638     *olen = 0;
639     block_size = mbedtls_cipher_get_block_size(ctx);
640     if (0 == block_size) {
641         return MBEDTLS_ERR_CIPHER_INVALID_CONTEXT;
642     }
643 
644     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_ECB) {
645         if (ilen != block_size) {
646             return MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED;
647         }
648 
649         *olen = ilen;
650 
651         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->ecb_func(ctx->cipher_ctx,
652                                                                             ctx->operation, input,
653                                                                             output))) {
654             return ret;
655         }
656 
657         return 0;
658     }
659 
660 #if defined(MBEDTLS_GCM_C)
661     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_GCM) {
662         return mbedtls_gcm_update((mbedtls_gcm_context *) ctx->cipher_ctx,
663                                   input, ilen,
664                                   output, ilen, olen);
665     }
666 #endif
667 
668 #if defined(MBEDTLS_CCM_C)
669     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_CCM_STAR_NO_TAG) {
670         return mbedtls_ccm_update((mbedtls_ccm_context *) ctx->cipher_ctx,
671                                   input, ilen,
672                                   output, ilen, olen);
673     }
674 #endif
675 
676 #if defined(MBEDTLS_CHACHAPOLY_C)
677     if (((mbedtls_cipher_type_t) ctx->cipher_info->type) == MBEDTLS_CIPHER_CHACHA20_POLY1305) {
678         *olen = ilen;
679         return mbedtls_chachapoly_update((mbedtls_chachapoly_context *) ctx->cipher_ctx,
680                                          ilen, input, output);
681     }
682 #endif
683 
684     if (input == output &&
685         (ctx->unprocessed_len != 0 || ilen % block_size)) {
686         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
687     }
688 
689 #if defined(MBEDTLS_CIPHER_MODE_CBC)
690     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_CBC) {
691         size_t copy_len = 0;
692 
693         /*
694          * If there is not enough data for a full block, cache it.
695          */
696         if ((ctx->operation == MBEDTLS_DECRYPT && NULL != ctx->add_padding &&
697              ilen <= block_size - ctx->unprocessed_len) ||
698             (ctx->operation == MBEDTLS_DECRYPT && NULL == ctx->add_padding &&
699              ilen < block_size - ctx->unprocessed_len) ||
700             (ctx->operation == MBEDTLS_ENCRYPT &&
701              ilen < block_size - ctx->unprocessed_len)) {
702             memcpy(&(ctx->unprocessed_data[ctx->unprocessed_len]), input,
703                    ilen);
704 
705             ctx->unprocessed_len += ilen;
706             return 0;
707         }
708 
709         /*
710          * Process cached data first
711          */
712         if (0 != ctx->unprocessed_len) {
713             copy_len = block_size - ctx->unprocessed_len;
714 
715             memcpy(&(ctx->unprocessed_data[ctx->unprocessed_len]), input,
716                    copy_len);
717 
718             if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->cbc_func(ctx->cipher_ctx,
719                                                                                 ctx->operation,
720                                                                                 block_size, ctx->iv,
721                                                                                 ctx->
722                                                                                 unprocessed_data,
723                                                                                 output))) {
724                 return ret;
725             }
726 
727             *olen += block_size;
728             output += block_size;
729             ctx->unprocessed_len = 0;
730 
731             input += copy_len;
732             ilen -= copy_len;
733         }
734 
735         /*
736          * Cache final, incomplete block
737          */
738         if (0 != ilen) {
739             /* Encryption: only cache partial blocks
740              * Decryption w/ padding: always keep at least one whole block
741              * Decryption w/o padding: only cache partial blocks
742              */
743             copy_len = ilen % block_size;
744             if (copy_len == 0 &&
745                 ctx->operation == MBEDTLS_DECRYPT &&
746                 NULL != ctx->add_padding) {
747                 copy_len = block_size;
748             }
749 
750             memcpy(ctx->unprocessed_data, &(input[ilen - copy_len]),
751                    copy_len);
752 
753             ctx->unprocessed_len += copy_len;
754             ilen -= copy_len;
755         }
756 
757         /*
758          * Process remaining full blocks
759          */
760         if (ilen) {
761             if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->cbc_func(ctx->cipher_ctx,
762                                                                                 ctx->operation,
763                                                                                 ilen, ctx->iv,
764                                                                                 input,
765                                                                                 output))) {
766                 return ret;
767             }
768 
769             *olen += ilen;
770         }
771 
772         return 0;
773     }
774 #endif /* MBEDTLS_CIPHER_MODE_CBC */
775 
776 #if defined(MBEDTLS_CIPHER_MODE_CFB)
777     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_CFB) {
778         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->cfb_func(ctx->cipher_ctx,
779                                                                             ctx->operation, ilen,
780                                                                             &ctx->unprocessed_len,
781                                                                             ctx->iv,
782                                                                             input, output))) {
783             return ret;
784         }
785 
786         *olen = ilen;
787 
788         return 0;
789     }
790 #endif /* MBEDTLS_CIPHER_MODE_CFB */
791 
792 #if defined(MBEDTLS_CIPHER_MODE_OFB)
793     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_OFB) {
794         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->ofb_func(ctx->cipher_ctx,
795                                                                             ilen,
796                                                                             &ctx->unprocessed_len,
797                                                                             ctx->iv,
798                                                                             input, output))) {
799             return ret;
800         }
801 
802         *olen = ilen;
803 
804         return 0;
805     }
806 #endif /* MBEDTLS_CIPHER_MODE_OFB */
807 
808 #if defined(MBEDTLS_CIPHER_MODE_CTR)
809     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_CTR) {
810         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->ctr_func(ctx->cipher_ctx,
811                                                                             ilen,
812                                                                             &ctx->unprocessed_len,
813                                                                             ctx->iv,
814                                                                             ctx->unprocessed_data,
815                                                                             input, output))) {
816             return ret;
817         }
818 
819         *olen = ilen;
820 
821         return 0;
822     }
823 #endif /* MBEDTLS_CIPHER_MODE_CTR */
824 
825 #if defined(MBEDTLS_CIPHER_MODE_XTS)
826     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_XTS) {
827         if (ctx->unprocessed_len > 0) {
828             /* We can only process an entire data unit at a time. */
829             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
830         }
831 
832         ret = mbedtls_cipher_get_base(ctx->cipher_info)->xts_func(ctx->cipher_ctx,
833                                                                   ctx->operation,
834                                                                   ilen,
835                                                                   ctx->iv,
836                                                                   input,
837                                                                   output);
838         if (ret != 0) {
839             return ret;
840         }
841 
842         *olen = ilen;
843 
844         return 0;
845     }
846 #endif /* MBEDTLS_CIPHER_MODE_XTS */
847 
848 #if defined(MBEDTLS_CIPHER_MODE_STREAM)
849     if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) == MBEDTLS_MODE_STREAM) {
850         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->stream_func(ctx->cipher_ctx,
851                                                                                ilen, input,
852                                                                                output))) {
853             return ret;
854         }
855 
856         *olen = ilen;
857 
858         return 0;
859     }
860 #endif /* MBEDTLS_CIPHER_MODE_STREAM */
861 
862     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
863 }
864 
865 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
866 #if defined(MBEDTLS_CIPHER_PADDING_PKCS7)
867 /*
868  * PKCS7 (and PKCS5) padding: fill with ll bytes, with ll = padding_len
869  */
add_pkcs_padding(unsigned char * output,size_t output_len,size_t data_len)870 static void add_pkcs_padding(unsigned char *output, size_t output_len,
871                              size_t data_len)
872 {
873     size_t padding_len = output_len - data_len;
874     unsigned char i;
875 
876     for (i = 0; i < padding_len; i++) {
877         output[data_len + i] = (unsigned char) padding_len;
878     }
879 }
880 
881 /*
882  * Get the length of the PKCS7 padding.
883  *
884  * Note: input_len must be the block size of the cipher.
885  */
mbedtls_get_pkcs_padding(unsigned char * input,size_t input_len,size_t * data_len,size_t * invalid_padding)886 MBEDTLS_STATIC_TESTABLE int mbedtls_get_pkcs_padding(unsigned char *input,
887                                                      size_t input_len,
888                                                      size_t *data_len,
889                                                      size_t *invalid_padding)
890 {
891     size_t i, pad_idx;
892     unsigned char padding_len;
893 
894     if (NULL == input || NULL == data_len) {
895         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
896     }
897 
898     padding_len = input[input_len - 1];
899 
900     mbedtls_ct_condition_t bad = mbedtls_ct_uint_gt(padding_len, input_len);
901     bad = mbedtls_ct_bool_or(bad, mbedtls_ct_uint_eq(padding_len, 0));
902 
903     /* The number of bytes checked must be independent of padding_len,
904      * so pick input_len, which is usually 8 or 16 (one block) */
905     pad_idx = input_len - padding_len;
906     for (i = 0; i < input_len; i++) {
907         mbedtls_ct_condition_t in_padding = mbedtls_ct_uint_ge(i, pad_idx);
908         mbedtls_ct_condition_t different  = mbedtls_ct_uint_ne(input[i], padding_len);
909         bad = mbedtls_ct_bool_or(bad, mbedtls_ct_bool_and(in_padding, different));
910     }
911 
912     /* If the padding is invalid, set the output length to 0 */
913     *data_len = mbedtls_ct_if(bad, 0, input_len - padding_len);
914 
915     *invalid_padding = mbedtls_ct_size_if_else_0(bad, SIZE_MAX);
916     return 0;
917 }
918 #endif /* MBEDTLS_CIPHER_PADDING_PKCS7 */
919 
920 #if defined(MBEDTLS_CIPHER_PADDING_ONE_AND_ZEROS)
921 /*
922  * One and zeros padding: fill with 80 00 ... 00
923  */
add_one_and_zeros_padding(unsigned char * output,size_t output_len,size_t data_len)924 static void add_one_and_zeros_padding(unsigned char *output,
925                                       size_t output_len, size_t data_len)
926 {
927     size_t padding_len = output_len - data_len;
928     unsigned char i = 0;
929 
930     output[data_len] = 0x80;
931     for (i = 1; i < padding_len; i++) {
932         output[data_len + i] = 0x00;
933     }
934 }
935 
get_one_and_zeros_padding(unsigned char * input,size_t input_len,size_t * data_len,size_t * invalid_padding)936 static int get_one_and_zeros_padding(unsigned char *input, size_t input_len,
937                                      size_t *data_len, size_t *invalid_padding)
938 {
939     if (NULL == input || NULL == data_len) {
940         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
941     }
942 
943     mbedtls_ct_condition_t in_padding = MBEDTLS_CT_TRUE;
944     mbedtls_ct_condition_t bad = MBEDTLS_CT_TRUE;
945 
946     *data_len = 0;
947 
948     for (ptrdiff_t i = (ptrdiff_t) (input_len) - 1; i >= 0; i--) {
949         mbedtls_ct_condition_t is_nonzero = mbedtls_ct_bool(input[i]);
950 
951         mbedtls_ct_condition_t hit_first_nonzero = mbedtls_ct_bool_and(is_nonzero, in_padding);
952 
953         *data_len = mbedtls_ct_size_if(hit_first_nonzero, i, *data_len);
954 
955         bad = mbedtls_ct_bool_if(hit_first_nonzero, mbedtls_ct_uint_ne(input[i], 0x80), bad);
956 
957         in_padding = mbedtls_ct_bool_and(in_padding, mbedtls_ct_bool_not(is_nonzero));
958     }
959 
960     *invalid_padding = mbedtls_ct_size_if_else_0(bad, SIZE_MAX);
961     return 0;
962 }
963 #endif /* MBEDTLS_CIPHER_PADDING_ONE_AND_ZEROS */
964 
965 #if defined(MBEDTLS_CIPHER_PADDING_ZEROS_AND_LEN)
966 /*
967  * Zeros and len padding: fill with 00 ... 00 ll, where ll is padding length
968  */
add_zeros_and_len_padding(unsigned char * output,size_t output_len,size_t data_len)969 static void add_zeros_and_len_padding(unsigned char *output,
970                                       size_t output_len, size_t data_len)
971 {
972     size_t padding_len = output_len - data_len;
973     unsigned char i = 0;
974 
975     for (i = 1; i < padding_len; i++) {
976         output[data_len + i - 1] = 0x00;
977     }
978     output[output_len - 1] = (unsigned char) padding_len;
979 }
980 
get_zeros_and_len_padding(unsigned char * input,size_t input_len,size_t * data_len,size_t * invalid_padding)981 static int get_zeros_and_len_padding(unsigned char *input, size_t input_len,
982                                      size_t *data_len, size_t *invalid_padding)
983 {
984     size_t i, pad_idx;
985     unsigned char padding_len;
986     mbedtls_ct_condition_t bad;
987 
988     if (NULL == input || NULL == data_len) {
989         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
990     }
991 
992     padding_len = input[input_len - 1];
993     *data_len = input_len - padding_len;
994 
995     /* Avoid logical || since it results in a branch */
996     bad = mbedtls_ct_uint_gt(padding_len, input_len);
997     bad = mbedtls_ct_bool_or(bad, mbedtls_ct_uint_eq(padding_len, 0));
998 
999     /* The number of bytes checked must be independent of padding_len */
1000     pad_idx = input_len - padding_len;
1001     for (i = 0; i < input_len - 1; i++) {
1002         mbedtls_ct_condition_t is_padding = mbedtls_ct_uint_ge(i, pad_idx);
1003         mbedtls_ct_condition_t nonzero_pad_byte;
1004         nonzero_pad_byte = mbedtls_ct_bool_if_else_0(is_padding, mbedtls_ct_bool(input[i]));
1005         bad = mbedtls_ct_bool_or(bad, nonzero_pad_byte);
1006     }
1007 
1008     *invalid_padding = mbedtls_ct_size_if_else_0(bad, SIZE_MAX);
1009     return 0;
1010 }
1011 #endif /* MBEDTLS_CIPHER_PADDING_ZEROS_AND_LEN */
1012 
1013 #if defined(MBEDTLS_CIPHER_PADDING_ZEROS)
1014 /*
1015  * Zero padding: fill with 00 ... 00
1016  */
add_zeros_padding(unsigned char * output,size_t output_len,size_t data_len)1017 static void add_zeros_padding(unsigned char *output,
1018                               size_t output_len, size_t data_len)
1019 {
1020     memset(output + data_len, 0, output_len - data_len);
1021 }
1022 
get_zeros_padding(unsigned char * input,size_t input_len,size_t * data_len,size_t * invalid_padding)1023 static int get_zeros_padding(unsigned char *input, size_t input_len,
1024                              size_t *data_len, size_t *invalid_padding)
1025 {
1026     size_t i;
1027     mbedtls_ct_condition_t done = MBEDTLS_CT_FALSE, prev_done;
1028 
1029     if (NULL == input || NULL == data_len) {
1030         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1031     }
1032 
1033     *data_len = 0;
1034     for (i = input_len; i > 0; i--) {
1035         prev_done = done;
1036         done = mbedtls_ct_bool_or(done, mbedtls_ct_uint_ne(input[i-1], 0));
1037         *data_len = mbedtls_ct_size_if(mbedtls_ct_bool_ne(done, prev_done), i, *data_len);
1038     }
1039 
1040     *invalid_padding = 0;
1041     return 0;
1042 }
1043 #endif /* MBEDTLS_CIPHER_PADDING_ZEROS */
1044 
1045 /*
1046  * No padding: don't pad :)
1047  *
1048  * There is no add_padding function (check for NULL in mbedtls_cipher_finish)
1049  * but a trivial get_padding function
1050  */
get_no_padding(unsigned char * input,size_t input_len,size_t * data_len,size_t * invalid_padding)1051 static int get_no_padding(unsigned char *input, size_t input_len,
1052                           size_t *data_len, size_t *invalid_padding)
1053 {
1054     if (NULL == input || NULL == data_len) {
1055         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1056     }
1057 
1058     *data_len = input_len;
1059     *invalid_padding = 0;
1060     return 0;
1061 }
1062 #endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */
1063 
mbedtls_cipher_finish_padded(mbedtls_cipher_context_t * ctx,unsigned char * output,size_t * olen,size_t * invalid_padding)1064 int mbedtls_cipher_finish_padded(mbedtls_cipher_context_t *ctx,
1065                                  unsigned char *output, size_t *olen,
1066                                  size_t *invalid_padding)
1067 {
1068     if (ctx->cipher_info == NULL) {
1069         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1070     }
1071 
1072 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1073     if (ctx->psa_enabled == 1) {
1074         /* While PSA Crypto has an API for multipart
1075          * operations, we currently don't make it
1076          * accessible through the cipher layer. */
1077         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1078     }
1079 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1080 
1081     *olen = 0;
1082     *invalid_padding = 0;
1083 
1084 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
1085     /* CBC mode requires padding so we make sure a call to
1086      * mbedtls_cipher_set_padding_mode has been done successfully. */
1087     if (MBEDTLS_MODE_CBC == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1088         if (ctx->get_padding == NULL) {
1089             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1090         }
1091     }
1092 #endif
1093 
1094     if (MBEDTLS_MODE_CFB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1095         MBEDTLS_MODE_OFB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1096         MBEDTLS_MODE_CTR == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1097         MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1098         MBEDTLS_MODE_CCM_STAR_NO_TAG == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1099         MBEDTLS_MODE_XTS == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1100         MBEDTLS_MODE_STREAM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1101         return 0;
1102     }
1103 
1104     if ((MBEDTLS_CIPHER_CHACHA20          == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) ||
1105         (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type))) {
1106         return 0;
1107     }
1108 
1109     if (MBEDTLS_MODE_ECB == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1110         if (ctx->unprocessed_len != 0) {
1111             return MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED;
1112         }
1113 
1114         return 0;
1115     }
1116 
1117 #if defined(MBEDTLS_CIPHER_MODE_CBC)
1118     if (MBEDTLS_MODE_CBC == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1119         int ret = 0;
1120 
1121         if (MBEDTLS_ENCRYPT == ctx->operation) {
1122             /* check for 'no padding' mode */
1123             if (NULL == ctx->add_padding) {
1124                 if (0 != ctx->unprocessed_len) {
1125                     return MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED;
1126                 }
1127 
1128                 return 0;
1129             }
1130 
1131             ctx->add_padding(ctx->unprocessed_data, mbedtls_cipher_get_iv_size(ctx),
1132                              ctx->unprocessed_len);
1133         } else if (mbedtls_cipher_get_block_size(ctx) != ctx->unprocessed_len) {
1134             /*
1135              * For decrypt operations, expect a full block,
1136              * or an empty block if no padding
1137              */
1138             if (NULL == ctx->add_padding && 0 == ctx->unprocessed_len) {
1139                 return 0;
1140             }
1141 
1142             return MBEDTLS_ERR_CIPHER_FULL_BLOCK_EXPECTED;
1143         }
1144 
1145         /* cipher block */
1146         if (0 != (ret = mbedtls_cipher_get_base(ctx->cipher_info)->cbc_func(ctx->cipher_ctx,
1147                                                                             ctx->operation,
1148                                                                             mbedtls_cipher_get_block_size(
1149                                                                                 ctx),
1150                                                                             ctx->iv,
1151                                                                             ctx->unprocessed_data,
1152                                                                             output))) {
1153             return ret;
1154         }
1155 
1156         /* Set output size for decryption */
1157         if (MBEDTLS_DECRYPT == ctx->operation) {
1158             return ctx->get_padding(output, mbedtls_cipher_get_block_size(ctx),
1159                                     olen, invalid_padding);
1160         }
1161 
1162         /* Set output size for encryption */
1163         *olen = mbedtls_cipher_get_block_size(ctx);
1164         return 0;
1165     }
1166 #else
1167     ((void) output);
1168 #endif /* MBEDTLS_CIPHER_MODE_CBC */
1169 
1170     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1171 }
1172 
mbedtls_cipher_finish(mbedtls_cipher_context_t * ctx,unsigned char * output,size_t * olen)1173 int mbedtls_cipher_finish(mbedtls_cipher_context_t *ctx,
1174                           unsigned char *output, size_t *olen)
1175 {
1176     size_t invalid_padding = 0;
1177     int ret = mbedtls_cipher_finish_padded(ctx, output, olen,
1178                                            &invalid_padding);
1179     if (ret == 0) {
1180         ret = mbedtls_ct_error_if_else_0(invalid_padding,
1181                                          MBEDTLS_ERR_CIPHER_INVALID_PADDING);
1182     }
1183     return ret;
1184 }
1185 
1186 #if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
mbedtls_cipher_set_padding_mode(mbedtls_cipher_context_t * ctx,mbedtls_cipher_padding_t mode)1187 int mbedtls_cipher_set_padding_mode(mbedtls_cipher_context_t *ctx,
1188                                     mbedtls_cipher_padding_t mode)
1189 {
1190     if (NULL == ctx->cipher_info ||
1191         MBEDTLS_MODE_CBC != ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1192         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1193     }
1194 
1195 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1196     if (ctx->psa_enabled == 1) {
1197         /* While PSA Crypto knows about CBC padding
1198          * schemes, we currently don't make them
1199          * accessible through the cipher layer. */
1200         if (mode != MBEDTLS_PADDING_NONE) {
1201             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1202         }
1203 
1204         return 0;
1205     }
1206 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1207 
1208     switch (mode) {
1209 #if defined(MBEDTLS_CIPHER_PADDING_PKCS7)
1210         case MBEDTLS_PADDING_PKCS7:
1211             ctx->add_padding = add_pkcs_padding;
1212             ctx->get_padding = mbedtls_get_pkcs_padding;
1213             break;
1214 #endif
1215 #if defined(MBEDTLS_CIPHER_PADDING_ONE_AND_ZEROS)
1216         case MBEDTLS_PADDING_ONE_AND_ZEROS:
1217             ctx->add_padding = add_one_and_zeros_padding;
1218             ctx->get_padding = get_one_and_zeros_padding;
1219             break;
1220 #endif
1221 #if defined(MBEDTLS_CIPHER_PADDING_ZEROS_AND_LEN)
1222         case MBEDTLS_PADDING_ZEROS_AND_LEN:
1223             ctx->add_padding = add_zeros_and_len_padding;
1224             ctx->get_padding = get_zeros_and_len_padding;
1225             break;
1226 #endif
1227 #if defined(MBEDTLS_CIPHER_PADDING_ZEROS)
1228         case MBEDTLS_PADDING_ZEROS:
1229             ctx->add_padding = add_zeros_padding;
1230             ctx->get_padding = get_zeros_padding;
1231             break;
1232 #endif
1233         case MBEDTLS_PADDING_NONE:
1234             ctx->add_padding = NULL;
1235             ctx->get_padding = get_no_padding;
1236             break;
1237 
1238         default:
1239             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1240     }
1241 
1242     return 0;
1243 }
1244 #endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */
1245 
1246 #if defined(MBEDTLS_GCM_C) || defined(MBEDTLS_CHACHAPOLY_C)
mbedtls_cipher_write_tag(mbedtls_cipher_context_t * ctx,unsigned char * tag,size_t tag_len)1247 int mbedtls_cipher_write_tag(mbedtls_cipher_context_t *ctx,
1248                              unsigned char *tag, size_t tag_len)
1249 {
1250     if (ctx->cipher_info == NULL) {
1251         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1252     }
1253 
1254     if (MBEDTLS_ENCRYPT != ctx->operation) {
1255         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1256     }
1257 
1258 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1259     if (ctx->psa_enabled == 1) {
1260         /* While PSA Crypto has an API for multipart
1261          * operations, we currently don't make it
1262          * accessible through the cipher layer. */
1263         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1264     }
1265 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1266 
1267 #if defined(MBEDTLS_GCM_C)
1268     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1269         size_t output_length;
1270         /* The code here doesn't yet support alternative implementations
1271          * that can delay up to a block of output. */
1272         return mbedtls_gcm_finish((mbedtls_gcm_context *) ctx->cipher_ctx,
1273                                   NULL, 0, &output_length,
1274                                   tag, tag_len);
1275     }
1276 #endif
1277 
1278 #if defined(MBEDTLS_CHACHAPOLY_C)
1279     if (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) {
1280         /* Don't allow truncated MAC for Poly1305 */
1281         if (tag_len != 16U) {
1282             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1283         }
1284 
1285         return mbedtls_chachapoly_finish(
1286             (mbedtls_chachapoly_context *) ctx->cipher_ctx, tag);
1287     }
1288 #endif
1289 
1290     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1291 }
1292 
mbedtls_cipher_check_tag(mbedtls_cipher_context_t * ctx,const unsigned char * tag,size_t tag_len)1293 int mbedtls_cipher_check_tag(mbedtls_cipher_context_t *ctx,
1294                              const unsigned char *tag, size_t tag_len)
1295 {
1296     unsigned char check_tag[16];
1297     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1298 
1299     if (ctx->cipher_info == NULL) {
1300         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1301     }
1302 
1303     if (MBEDTLS_DECRYPT != ctx->operation) {
1304         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1305     }
1306 
1307 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1308     if (ctx->psa_enabled == 1) {
1309         /* While PSA Crypto has an API for multipart
1310          * operations, we currently don't make it
1311          * accessible through the cipher layer. */
1312         return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1313     }
1314 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1315 
1316     /* Status to return on a non-authenticated algorithm. */
1317     ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1318 
1319 #if defined(MBEDTLS_GCM_C)
1320     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1321         size_t output_length;
1322         /* The code here doesn't yet support alternative implementations
1323          * that can delay up to a block of output. */
1324 
1325         if (tag_len > sizeof(check_tag)) {
1326             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1327         }
1328 
1329         if (0 != (ret = mbedtls_gcm_finish(
1330                       (mbedtls_gcm_context *) ctx->cipher_ctx,
1331                       NULL, 0, &output_length,
1332                       check_tag, tag_len))) {
1333             return ret;
1334         }
1335 
1336         /* Check the tag in "constant-time" */
1337         if (mbedtls_ct_memcmp(tag, check_tag, tag_len) != 0) {
1338             ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1339             goto exit;
1340         }
1341     }
1342 #endif /* MBEDTLS_GCM_C */
1343 
1344 #if defined(MBEDTLS_CHACHAPOLY_C)
1345     if (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) {
1346         /* Don't allow truncated MAC for Poly1305 */
1347         if (tag_len != sizeof(check_tag)) {
1348             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1349         }
1350 
1351         ret = mbedtls_chachapoly_finish(
1352             (mbedtls_chachapoly_context *) ctx->cipher_ctx, check_tag);
1353         if (ret != 0) {
1354             return ret;
1355         }
1356 
1357         /* Check the tag in "constant-time" */
1358         if (mbedtls_ct_memcmp(tag, check_tag, tag_len) != 0) {
1359             ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1360             goto exit;
1361         }
1362     }
1363 #endif /* MBEDTLS_CHACHAPOLY_C */
1364 
1365 exit:
1366     mbedtls_platform_zeroize(check_tag, tag_len);
1367     return ret;
1368 }
1369 #endif /* MBEDTLS_GCM_C || MBEDTLS_CHACHAPOLY_C */
1370 
1371 /*
1372  * Packet-oriented wrapper for non-AEAD modes
1373  */
mbedtls_cipher_crypt(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len,const unsigned char * input,size_t ilen,unsigned char * output,size_t * olen)1374 int mbedtls_cipher_crypt(mbedtls_cipher_context_t *ctx,
1375                          const unsigned char *iv, size_t iv_len,
1376                          const unsigned char *input, size_t ilen,
1377                          unsigned char *output, size_t *olen)
1378 {
1379     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1380     size_t finish_olen;
1381 
1382 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1383     if (ctx->psa_enabled == 1) {
1384         /* As in the non-PSA case, we don't check that
1385          * a key has been set. If not, the key slot will
1386          * still be in its default state of 0, which is
1387          * guaranteed to be invalid, hence the PSA-call
1388          * below will gracefully fail. */
1389         mbedtls_cipher_context_psa * const cipher_psa =
1390             (mbedtls_cipher_context_psa *) ctx->cipher_ctx;
1391 
1392         psa_status_t status;
1393         psa_cipher_operation_t cipher_op = PSA_CIPHER_OPERATION_INIT;
1394         size_t part_len;
1395 
1396         if (ctx->operation == MBEDTLS_DECRYPT) {
1397             status = psa_cipher_decrypt_setup(&cipher_op,
1398                                               cipher_psa->slot,
1399                                               cipher_psa->alg);
1400         } else if (ctx->operation == MBEDTLS_ENCRYPT) {
1401             status = psa_cipher_encrypt_setup(&cipher_op,
1402                                               cipher_psa->slot,
1403                                               cipher_psa->alg);
1404         } else {
1405             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1406         }
1407 
1408         /* In the following, we can immediately return on an error,
1409          * because the PSA Crypto API guarantees that cipher operations
1410          * are terminated by unsuccessful calls to psa_cipher_update(),
1411          * and by any call to psa_cipher_finish(). */
1412         if (status != PSA_SUCCESS) {
1413             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1414         }
1415 
1416         if (((mbedtls_cipher_mode_t) ctx->cipher_info->mode) != MBEDTLS_MODE_ECB) {
1417             status = psa_cipher_set_iv(&cipher_op, iv, iv_len);
1418             if (status != PSA_SUCCESS) {
1419                 return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1420             }
1421         }
1422 
1423         status = psa_cipher_update(&cipher_op,
1424                                    input, ilen,
1425                                    output, ilen, olen);
1426         if (status != PSA_SUCCESS) {
1427             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1428         }
1429 
1430         status = psa_cipher_finish(&cipher_op,
1431                                    output + *olen, ilen - *olen,
1432                                    &part_len);
1433         if (status != PSA_SUCCESS) {
1434             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1435         }
1436 
1437         *olen += part_len;
1438         return 0;
1439     }
1440 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1441 
1442     if ((ret = mbedtls_cipher_set_iv(ctx, iv, iv_len)) != 0) {
1443         return ret;
1444     }
1445 
1446     if ((ret = mbedtls_cipher_reset(ctx)) != 0) {
1447         return ret;
1448     }
1449 
1450     if ((ret = mbedtls_cipher_update(ctx, input, ilen,
1451                                      output, olen)) != 0) {
1452         return ret;
1453     }
1454 
1455     size_t invalid_padding = 0;
1456     if ((ret = mbedtls_cipher_finish_padded(ctx, output + *olen,
1457                                             &finish_olen,
1458                                             &invalid_padding)) != 0) {
1459         return ret;
1460     }
1461     *olen += finish_olen;
1462 
1463     ret = mbedtls_ct_error_if_else_0(invalid_padding,
1464                                      MBEDTLS_ERR_CIPHER_INVALID_PADDING);
1465     return ret;
1466 }
1467 
1468 #if defined(MBEDTLS_CIPHER_MODE_AEAD)
1469 /*
1470  * Packet-oriented encryption for AEAD modes: internal function used by
1471  * mbedtls_cipher_auth_encrypt_ext().
1472  */
mbedtls_cipher_aead_encrypt(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len,const unsigned char * ad,size_t ad_len,const unsigned char * input,size_t ilen,unsigned char * output,size_t * olen,unsigned char * tag,size_t tag_len)1473 static int mbedtls_cipher_aead_encrypt(mbedtls_cipher_context_t *ctx,
1474                                        const unsigned char *iv, size_t iv_len,
1475                                        const unsigned char *ad, size_t ad_len,
1476                                        const unsigned char *input, size_t ilen,
1477                                        unsigned char *output, size_t *olen,
1478                                        unsigned char *tag, size_t tag_len)
1479 {
1480 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1481     if (ctx->psa_enabled == 1) {
1482         /* As in the non-PSA case, we don't check that
1483          * a key has been set. If not, the key slot will
1484          * still be in its default state of 0, which is
1485          * guaranteed to be invalid, hence the PSA-call
1486          * below will gracefully fail. */
1487         mbedtls_cipher_context_psa * const cipher_psa =
1488             (mbedtls_cipher_context_psa *) ctx->cipher_ctx;
1489 
1490         psa_status_t status;
1491 
1492         /* PSA Crypto API always writes the authentication tag
1493          * at the end of the encrypted message. */
1494         if (output == NULL || tag != output + ilen) {
1495             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1496         }
1497 
1498         status = psa_aead_encrypt(cipher_psa->slot,
1499                                   cipher_psa->alg,
1500                                   iv, iv_len,
1501                                   ad, ad_len,
1502                                   input, ilen,
1503                                   output, ilen + tag_len, olen);
1504         if (status != PSA_SUCCESS) {
1505             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1506         }
1507 
1508         *olen -= tag_len;
1509         return 0;
1510     }
1511 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1512 
1513 #if defined(MBEDTLS_GCM_C)
1514     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1515         *olen = ilen;
1516         return mbedtls_gcm_crypt_and_tag(ctx->cipher_ctx, MBEDTLS_GCM_ENCRYPT,
1517                                          ilen, iv, iv_len, ad, ad_len,
1518                                          input, output, tag_len, tag);
1519     }
1520 #endif /* MBEDTLS_GCM_C */
1521 #if defined(MBEDTLS_CCM_C)
1522     if (MBEDTLS_MODE_CCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1523         *olen = ilen;
1524         return mbedtls_ccm_encrypt_and_tag(ctx->cipher_ctx, ilen,
1525                                            iv, iv_len, ad, ad_len, input, output,
1526                                            tag, tag_len);
1527     }
1528 #endif /* MBEDTLS_CCM_C */
1529 #if defined(MBEDTLS_CHACHAPOLY_C)
1530     if (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) {
1531         /* ChachaPoly has fixed length nonce and MAC (tag) */
1532         if ((iv_len != mbedtls_cipher_info_get_iv_size(ctx->cipher_info)) ||
1533             (tag_len != 16U)) {
1534             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1535         }
1536 
1537         *olen = ilen;
1538         return mbedtls_chachapoly_encrypt_and_tag(ctx->cipher_ctx,
1539                                                   ilen, iv, ad, ad_len, input, output, tag);
1540     }
1541 #endif /* MBEDTLS_CHACHAPOLY_C */
1542 
1543     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1544 }
1545 
1546 /*
1547  * Packet-oriented encryption for AEAD modes: internal function used by
1548  * mbedtls_cipher_auth_encrypt_ext().
1549  */
mbedtls_cipher_aead_decrypt(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len,const unsigned char * ad,size_t ad_len,const unsigned char * input,size_t ilen,unsigned char * output,size_t * olen,const unsigned char * tag,size_t tag_len)1550 static int mbedtls_cipher_aead_decrypt(mbedtls_cipher_context_t *ctx,
1551                                        const unsigned char *iv, size_t iv_len,
1552                                        const unsigned char *ad, size_t ad_len,
1553                                        const unsigned char *input, size_t ilen,
1554                                        unsigned char *output, size_t *olen,
1555                                        const unsigned char *tag, size_t tag_len)
1556 {
1557 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1558     if (ctx->psa_enabled == 1) {
1559         /* As in the non-PSA case, we don't check that
1560          * a key has been set. If not, the key slot will
1561          * still be in its default state of 0, which is
1562          * guaranteed to be invalid, hence the PSA-call
1563          * below will gracefully fail. */
1564         mbedtls_cipher_context_psa * const cipher_psa =
1565             (mbedtls_cipher_context_psa *) ctx->cipher_ctx;
1566 
1567         psa_status_t status;
1568 
1569         /* PSA Crypto API always writes the authentication tag
1570          * at the end of the encrypted message. */
1571         if (input == NULL || tag != input + ilen) {
1572             return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1573         }
1574 
1575         status = psa_aead_decrypt(cipher_psa->slot,
1576                                   cipher_psa->alg,
1577                                   iv, iv_len,
1578                                   ad, ad_len,
1579                                   input, ilen + tag_len,
1580                                   output, ilen, olen);
1581         if (status == PSA_ERROR_INVALID_SIGNATURE) {
1582             return MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1583         } else if (status != PSA_SUCCESS) {
1584             return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
1585         }
1586 
1587         return 0;
1588     }
1589 #endif /* MBEDTLS_USE_PSA_CRYPTO && !MBEDTLS_DEPRECATED_REMOVED */
1590 
1591 #if defined(MBEDTLS_GCM_C)
1592     if (MBEDTLS_MODE_GCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1593         int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1594 
1595         *olen = ilen;
1596         ret = mbedtls_gcm_auth_decrypt(ctx->cipher_ctx, ilen,
1597                                        iv, iv_len, ad, ad_len,
1598                                        tag, tag_len, input, output);
1599 
1600         if (ret == MBEDTLS_ERR_GCM_AUTH_FAILED) {
1601             ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1602         }
1603 
1604         return ret;
1605     }
1606 #endif /* MBEDTLS_GCM_C */
1607 #if defined(MBEDTLS_CCM_C)
1608     if (MBEDTLS_MODE_CCM == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) {
1609         int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1610 
1611         *olen = ilen;
1612         ret = mbedtls_ccm_auth_decrypt(ctx->cipher_ctx, ilen,
1613                                        iv, iv_len, ad, ad_len,
1614                                        input, output, tag, tag_len);
1615 
1616         if (ret == MBEDTLS_ERR_CCM_AUTH_FAILED) {
1617             ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1618         }
1619 
1620         return ret;
1621     }
1622 #endif /* MBEDTLS_CCM_C */
1623 #if defined(MBEDTLS_CHACHAPOLY_C)
1624     if (MBEDTLS_CIPHER_CHACHA20_POLY1305 == ((mbedtls_cipher_type_t) ctx->cipher_info->type)) {
1625         int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1626 
1627         /* ChachaPoly has fixed length nonce and MAC (tag) */
1628         if ((iv_len != mbedtls_cipher_info_get_iv_size(ctx->cipher_info)) ||
1629             (tag_len != 16U)) {
1630             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1631         }
1632 
1633         *olen = ilen;
1634         ret = mbedtls_chachapoly_auth_decrypt(ctx->cipher_ctx, ilen,
1635                                               iv, ad, ad_len, tag, input, output);
1636 
1637         if (ret == MBEDTLS_ERR_CHACHAPOLY_AUTH_FAILED) {
1638             ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
1639         }
1640 
1641         return ret;
1642     }
1643 #endif /* MBEDTLS_CHACHAPOLY_C */
1644 
1645     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1646 }
1647 #endif /* MBEDTLS_CIPHER_MODE_AEAD */
1648 
1649 #if defined(MBEDTLS_CIPHER_MODE_AEAD) || defined(MBEDTLS_NIST_KW_C)
1650 /*
1651  * Packet-oriented encryption for AEAD/NIST_KW: public function.
1652  */
mbedtls_cipher_auth_encrypt_ext(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len,const unsigned char * ad,size_t ad_len,const unsigned char * input,size_t ilen,unsigned char * output,size_t output_len,size_t * olen,size_t tag_len)1653 int mbedtls_cipher_auth_encrypt_ext(mbedtls_cipher_context_t *ctx,
1654                                     const unsigned char *iv, size_t iv_len,
1655                                     const unsigned char *ad, size_t ad_len,
1656                                     const unsigned char *input, size_t ilen,
1657                                     unsigned char *output, size_t output_len,
1658                                     size_t *olen, size_t tag_len)
1659 {
1660 #if defined(MBEDTLS_NIST_KW_C)
1661     if (
1662 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1663         ctx->psa_enabled == 0 &&
1664 #endif
1665         (MBEDTLS_MODE_KW == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1666          MBEDTLS_MODE_KWP == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode))) {
1667         mbedtls_nist_kw_mode_t mode =
1668             (MBEDTLS_MODE_KW == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) ?
1669             MBEDTLS_KW_MODE_KW : MBEDTLS_KW_MODE_KWP;
1670 
1671         /* There is no iv, tag or ad associated with KW and KWP,
1672          * so these length should be 0 as documented. */
1673         if (iv_len != 0 || tag_len != 0 || ad_len != 0) {
1674             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1675         }
1676 
1677         (void) iv;
1678         (void) ad;
1679 
1680         return mbedtls_nist_kw_wrap(ctx->cipher_ctx, mode, input, ilen,
1681                                     output, olen, output_len);
1682     }
1683 #endif /* MBEDTLS_NIST_KW_C */
1684 
1685 #if defined(MBEDTLS_CIPHER_MODE_AEAD)
1686     /* AEAD case: check length before passing on to shared function */
1687     if (output_len < ilen + tag_len) {
1688         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1689     }
1690 
1691     int ret = mbedtls_cipher_aead_encrypt(ctx, iv, iv_len, ad, ad_len,
1692                                           input, ilen, output, olen,
1693                                           output + ilen, tag_len);
1694     *olen += tag_len;
1695     return ret;
1696 #else
1697     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1698 #endif /* MBEDTLS_CIPHER_MODE_AEAD */
1699 }
1700 
1701 /*
1702  * Packet-oriented decryption for AEAD/NIST_KW: public function.
1703  */
mbedtls_cipher_auth_decrypt_ext(mbedtls_cipher_context_t * ctx,const unsigned char * iv,size_t iv_len,const unsigned char * ad,size_t ad_len,const unsigned char * input,size_t ilen,unsigned char * output,size_t output_len,size_t * olen,size_t tag_len)1704 int mbedtls_cipher_auth_decrypt_ext(mbedtls_cipher_context_t *ctx,
1705                                     const unsigned char *iv, size_t iv_len,
1706                                     const unsigned char *ad, size_t ad_len,
1707                                     const unsigned char *input, size_t ilen,
1708                                     unsigned char *output, size_t output_len,
1709                                     size_t *olen, size_t tag_len)
1710 {
1711 #if defined(MBEDTLS_NIST_KW_C)
1712     if (
1713 #if defined(MBEDTLS_USE_PSA_CRYPTO) && !defined(MBEDTLS_DEPRECATED_REMOVED)
1714         ctx->psa_enabled == 0 &&
1715 #endif
1716         (MBEDTLS_MODE_KW == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode) ||
1717          MBEDTLS_MODE_KWP == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode))) {
1718         mbedtls_nist_kw_mode_t mode =
1719             (MBEDTLS_MODE_KW == ((mbedtls_cipher_mode_t) ctx->cipher_info->mode)) ?
1720             MBEDTLS_KW_MODE_KW : MBEDTLS_KW_MODE_KWP;
1721 
1722         /* There is no iv, tag or ad associated with KW and KWP,
1723          * so these length should be 0 as documented. */
1724         if (iv_len != 0 || tag_len != 0 || ad_len != 0) {
1725             return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1726         }
1727 
1728         (void) iv;
1729         (void) ad;
1730 
1731         return mbedtls_nist_kw_unwrap(ctx->cipher_ctx, mode, input, ilen,
1732                                       output, olen, output_len);
1733     }
1734 #endif /* MBEDTLS_NIST_KW_C */
1735 
1736 #if defined(MBEDTLS_CIPHER_MODE_AEAD)
1737     /* AEAD case: check length before passing on to shared function */
1738     if (ilen < tag_len || output_len < ilen - tag_len) {
1739         return MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
1740     }
1741 
1742     return mbedtls_cipher_aead_decrypt(ctx, iv, iv_len, ad, ad_len,
1743                                        input, ilen - tag_len, output, olen,
1744                                        input + ilen - tag_len, tag_len);
1745 #else
1746     return MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
1747 #endif /* MBEDTLS_CIPHER_MODE_AEAD */
1748 }
1749 #endif /* MBEDTLS_CIPHER_MODE_AEAD || MBEDTLS_NIST_KW_C */
1750 
1751 #endif /* MBEDTLS_CIPHER_C */
1752