xref: /optee_os/lib/libutee/tee_api_operations.c (revision 91fc6bd89309eebdfbe3d7203a046958b8c5a3eb)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2014, STMicroelectronics International N.V.
4  */
5 #include <stdlib.h>
6 #include <string.h>
7 #include <string_ext.h>
8 
9 #include <tee_api.h>
10 #include <tee_api_defines_extensions.h>
11 #include <tee_internal_api_extensions.h>
12 #include <utee_syscalls.h>
13 #include <utee_defines.h>
14 #include <util.h>
15 #include "tee_api_private.h"
16 
17 struct __TEE_OperationHandle {
18 	TEE_OperationInfo info;
19 	TEE_ObjectHandle key1;
20 	TEE_ObjectHandle key2;
21 	uint32_t operationState;/* Operation state : INITIAL or ACTIVE */
22 	uint8_t *buffer;	/* buffer to collect complete blocks */
23 	bool buffer_two_blocks;	/* True if two blocks need to be buffered */
24 	size_t block_size;	/* Block size of cipher */
25 	size_t buffer_offs;	/* Offset in buffer */
26 	uint32_t state;		/* Handle to state in TEE Core */
27 	uint32_t ae_tag_len;	/*
28 				 * tag_len in bytes for AE operation else unused
29 				 */
30 };
31 
32 /* Cryptographic Operations API - Generic Operation Functions */
33 
34 TEE_Result TEE_AllocateOperation(TEE_OperationHandle *operation,
35 				 uint32_t algorithm, uint32_t mode,
36 				 uint32_t maxKeySize)
37 {
38 	TEE_Result res;
39 	TEE_OperationHandle op = TEE_HANDLE_NULL;
40 	uint32_t handle_state = 0;
41 	size_t block_size = 1;
42 	uint32_t req_key_usage;
43 	bool with_private_key = false;
44 	bool buffer_two_blocks = false;
45 
46 	if (!operation)
47 		TEE_Panic(0);
48 
49 	if (algorithm == TEE_ALG_AES_XTS)
50 		handle_state = TEE_HANDLE_FLAG_EXPECT_TWO_KEYS;
51 
52 	/* Check algorithm max key size */
53 	switch (algorithm) {
54 	case TEE_ALG_DSA_SHA1:
55 		if (maxKeySize < 512)
56 			return TEE_ERROR_NOT_SUPPORTED;
57 		if (maxKeySize > 1024)
58 			return TEE_ERROR_NOT_SUPPORTED;
59 		if (maxKeySize % 64 != 0)
60 			return TEE_ERROR_NOT_SUPPORTED;
61 		break;
62 
63 	case TEE_ALG_DSA_SHA224:
64 		if (maxKeySize != 2048)
65 			return TEE_ERROR_NOT_SUPPORTED;
66 		break;
67 
68 	case TEE_ALG_DSA_SHA256:
69 		if (maxKeySize != 2048 && maxKeySize != 3072)
70 			return TEE_ERROR_NOT_SUPPORTED;
71 		break;
72 
73 	case TEE_ALG_ECDSA_P192:
74 	case TEE_ALG_ECDH_P192:
75 		if (maxKeySize != 192)
76 			return TEE_ERROR_NOT_SUPPORTED;
77 		break;
78 
79 	case TEE_ALG_ECDSA_P224:
80 	case TEE_ALG_ECDH_P224:
81 		if (maxKeySize != 224)
82 			return TEE_ERROR_NOT_SUPPORTED;
83 		break;
84 
85 	case TEE_ALG_ECDSA_P256:
86 	case TEE_ALG_ECDH_P256:
87 	case TEE_ALG_SM2_PKE:
88 		if (maxKeySize != 256)
89 			return TEE_ERROR_NOT_SUPPORTED;
90 		break;
91 
92 	case TEE_ALG_ECDSA_P384:
93 	case TEE_ALG_ECDH_P384:
94 		if (maxKeySize != 384)
95 			return TEE_ERROR_NOT_SUPPORTED;
96 		break;
97 
98 	case TEE_ALG_ECDSA_P521:
99 	case TEE_ALG_ECDH_P521:
100 		if (maxKeySize != 521)
101 			return TEE_ERROR_NOT_SUPPORTED;
102 		break;
103 
104 	default:
105 		break;
106 	}
107 
108 	/* Check algorithm mode */
109 	switch (algorithm) {
110 	case TEE_ALG_AES_CTS:
111 	case TEE_ALG_AES_XTS:
112 		buffer_two_blocks = true;
113 		/* FALLTHROUGH */
114 	case TEE_ALG_AES_ECB_NOPAD:
115 	case TEE_ALG_AES_CBC_NOPAD:
116 	case TEE_ALG_AES_CCM:
117 	case TEE_ALG_DES_ECB_NOPAD:
118 	case TEE_ALG_DES_CBC_NOPAD:
119 	case TEE_ALG_DES3_ECB_NOPAD:
120 	case TEE_ALG_DES3_CBC_NOPAD:
121 	case TEE_ALG_SM4_ECB_NOPAD:
122 	case TEE_ALG_SM4_CBC_NOPAD:
123 	case TEE_ALG_SM4_CTR:
124 		if (TEE_ALG_GET_MAIN_ALG(algorithm) == TEE_MAIN_ALGO_AES)
125 			block_size = TEE_AES_BLOCK_SIZE;
126 		else if (TEE_ALG_GET_MAIN_ALG(algorithm) == TEE_MAIN_ALGO_SM4)
127 			block_size = TEE_SM4_BLOCK_SIZE;
128 		else
129 			block_size = TEE_DES_BLOCK_SIZE;
130 		/* FALLTHROUGH */
131 	case TEE_ALG_AES_CTR:
132 	case TEE_ALG_AES_GCM:
133 		if (mode == TEE_MODE_ENCRYPT)
134 			req_key_usage = TEE_USAGE_ENCRYPT;
135 		else if (mode == TEE_MODE_DECRYPT)
136 			req_key_usage = TEE_USAGE_DECRYPT;
137 		else
138 			return TEE_ERROR_NOT_SUPPORTED;
139 		break;
140 
141 #if defined(CFG_CRYPTO_RSASSA_NA1)
142 	case TEE_ALG_RSASSA_PKCS1_V1_5:
143 #endif
144 	case TEE_ALG_RSASSA_PKCS1_V1_5_MD5:
145 	case TEE_ALG_RSASSA_PKCS1_V1_5_SHA1:
146 	case TEE_ALG_RSASSA_PKCS1_V1_5_SHA224:
147 	case TEE_ALG_RSASSA_PKCS1_V1_5_SHA256:
148 	case TEE_ALG_RSASSA_PKCS1_V1_5_SHA384:
149 	case TEE_ALG_RSASSA_PKCS1_V1_5_SHA512:
150 	case TEE_ALG_RSASSA_PKCS1_PSS_MGF1_SHA1:
151 	case TEE_ALG_RSASSA_PKCS1_PSS_MGF1_SHA224:
152 	case TEE_ALG_RSASSA_PKCS1_PSS_MGF1_SHA256:
153 	case TEE_ALG_RSASSA_PKCS1_PSS_MGF1_SHA384:
154 	case TEE_ALG_RSASSA_PKCS1_PSS_MGF1_SHA512:
155 	case TEE_ALG_DSA_SHA1:
156 	case TEE_ALG_DSA_SHA224:
157 	case TEE_ALG_DSA_SHA256:
158 	case TEE_ALG_ECDSA_P192:
159 	case TEE_ALG_ECDSA_P224:
160 	case TEE_ALG_ECDSA_P256:
161 	case TEE_ALG_ECDSA_P384:
162 	case TEE_ALG_ECDSA_P521:
163 		if (mode == TEE_MODE_SIGN) {
164 			with_private_key = true;
165 			req_key_usage = TEE_USAGE_SIGN;
166 		} else if (mode == TEE_MODE_VERIFY) {
167 			req_key_usage = TEE_USAGE_VERIFY;
168 		} else {
169 			return TEE_ERROR_NOT_SUPPORTED;
170 		}
171 		break;
172 
173 	case TEE_ALG_RSAES_PKCS1_V1_5:
174 	case TEE_ALG_RSAES_PKCS1_OAEP_MGF1_SHA1:
175 	case TEE_ALG_RSAES_PKCS1_OAEP_MGF1_SHA224:
176 	case TEE_ALG_RSAES_PKCS1_OAEP_MGF1_SHA256:
177 	case TEE_ALG_RSAES_PKCS1_OAEP_MGF1_SHA384:
178 	case TEE_ALG_RSAES_PKCS1_OAEP_MGF1_SHA512:
179 	case TEE_ALG_SM2_PKE:
180 		if (mode == TEE_MODE_ENCRYPT) {
181 			req_key_usage = TEE_USAGE_ENCRYPT;
182 		} else if (mode == TEE_MODE_DECRYPT) {
183 			with_private_key = true;
184 			req_key_usage = TEE_USAGE_DECRYPT;
185 		} else {
186 			return TEE_ERROR_NOT_SUPPORTED;
187 		}
188 		break;
189 
190 	case TEE_ALG_RSA_NOPAD:
191 		if (mode == TEE_MODE_ENCRYPT) {
192 			req_key_usage = TEE_USAGE_ENCRYPT | TEE_USAGE_VERIFY;
193 		} else if (mode == TEE_MODE_DECRYPT) {
194 			with_private_key = true;
195 			req_key_usage = TEE_USAGE_DECRYPT | TEE_USAGE_SIGN;
196 		} else {
197 			return TEE_ERROR_NOT_SUPPORTED;
198 		}
199 		break;
200 
201 	case TEE_ALG_DH_DERIVE_SHARED_SECRET:
202 	case TEE_ALG_ECDH_P192:
203 	case TEE_ALG_ECDH_P224:
204 	case TEE_ALG_ECDH_P256:
205 	case TEE_ALG_ECDH_P384:
206 	case TEE_ALG_ECDH_P521:
207 	case TEE_ALG_HKDF_MD5_DERIVE_KEY:
208 	case TEE_ALG_HKDF_SHA1_DERIVE_KEY:
209 	case TEE_ALG_HKDF_SHA224_DERIVE_KEY:
210 	case TEE_ALG_HKDF_SHA256_DERIVE_KEY:
211 	case TEE_ALG_HKDF_SHA384_DERIVE_KEY:
212 	case TEE_ALG_HKDF_SHA512_DERIVE_KEY:
213 	case TEE_ALG_CONCAT_KDF_SHA1_DERIVE_KEY:
214 	case TEE_ALG_CONCAT_KDF_SHA224_DERIVE_KEY:
215 	case TEE_ALG_CONCAT_KDF_SHA256_DERIVE_KEY:
216 	case TEE_ALG_CONCAT_KDF_SHA384_DERIVE_KEY:
217 	case TEE_ALG_CONCAT_KDF_SHA512_DERIVE_KEY:
218 	case TEE_ALG_PBKDF2_HMAC_SHA1_DERIVE_KEY:
219 		if (mode != TEE_MODE_DERIVE)
220 			return TEE_ERROR_NOT_SUPPORTED;
221 		with_private_key = true;
222 		req_key_usage = TEE_USAGE_DERIVE;
223 		break;
224 
225 	case TEE_ALG_MD5:
226 	case TEE_ALG_SHA1:
227 	case TEE_ALG_SHA224:
228 	case TEE_ALG_SHA256:
229 	case TEE_ALG_SHA384:
230 	case TEE_ALG_SHA512:
231 	case TEE_ALG_SM3:
232 		if (mode != TEE_MODE_DIGEST)
233 			return TEE_ERROR_NOT_SUPPORTED;
234 		/* v1.1: flags always set for digest operations */
235 		handle_state |= TEE_HANDLE_FLAG_KEY_SET;
236 		req_key_usage = 0;
237 		break;
238 
239 	case TEE_ALG_DES_CBC_MAC_NOPAD:
240 	case TEE_ALG_AES_CBC_MAC_NOPAD:
241 	case TEE_ALG_AES_CBC_MAC_PKCS5:
242 	case TEE_ALG_AES_CMAC:
243 	case TEE_ALG_DES_CBC_MAC_PKCS5:
244 	case TEE_ALG_DES3_CBC_MAC_NOPAD:
245 	case TEE_ALG_DES3_CBC_MAC_PKCS5:
246 	case TEE_ALG_HMAC_MD5:
247 	case TEE_ALG_HMAC_SHA1:
248 	case TEE_ALG_HMAC_SHA224:
249 	case TEE_ALG_HMAC_SHA256:
250 	case TEE_ALG_HMAC_SHA384:
251 	case TEE_ALG_HMAC_SHA512:
252 	case TEE_ALG_HMAC_SM3:
253 		if (mode != TEE_MODE_MAC)
254 			return TEE_ERROR_NOT_SUPPORTED;
255 		req_key_usage = TEE_USAGE_MAC;
256 		break;
257 
258 	default:
259 		return TEE_ERROR_NOT_SUPPORTED;
260 	}
261 
262 	op = TEE_Malloc(sizeof(*op), TEE_MALLOC_FILL_ZERO);
263 	if (!op)
264 		return TEE_ERROR_OUT_OF_MEMORY;
265 
266 	op->info.algorithm = algorithm;
267 	op->info.operationClass = TEE_ALG_GET_CLASS(algorithm);
268 #ifdef CFG_CRYPTO_RSASSA_NA1
269 	if (algorithm == TEE_ALG_RSASSA_PKCS1_V1_5)
270 		op->info.operationClass = TEE_OPERATION_ASYMMETRIC_SIGNATURE;
271 #endif
272 	op->info.mode = mode;
273 	op->info.maxKeySize = maxKeySize;
274 	op->info.requiredKeyUsage = req_key_usage;
275 	op->info.handleState = handle_state;
276 
277 	if (block_size > 1) {
278 		size_t buffer_size = block_size;
279 
280 		if (buffer_two_blocks)
281 			buffer_size *= 2;
282 
283 		op->buffer = TEE_Malloc(buffer_size,
284 					TEE_USER_MEM_HINT_NO_FILL_ZERO);
285 		if (op->buffer == NULL) {
286 			res = TEE_ERROR_OUT_OF_MEMORY;
287 			goto out;
288 		}
289 	}
290 	op->block_size = block_size;
291 	op->buffer_two_blocks = buffer_two_blocks;
292 
293 	if (TEE_ALG_GET_CLASS(algorithm) != TEE_OPERATION_DIGEST) {
294 		uint32_t mks = maxKeySize;
295 		TEE_ObjectType key_type = TEE_ALG_GET_KEY_TYPE(algorithm,
296 						       with_private_key);
297 
298 		/*
299 		 * If two keys are expected the max key size is the sum of
300 		 * the size of both keys.
301 		 */
302 		if (op->info.handleState & TEE_HANDLE_FLAG_EXPECT_TWO_KEYS)
303 			mks /= 2;
304 
305 		res = TEE_AllocateTransientObject(key_type, mks, &op->key1);
306 		if (res != TEE_SUCCESS)
307 			goto out;
308 
309 		if (op->info.handleState & TEE_HANDLE_FLAG_EXPECT_TWO_KEYS) {
310 			res = TEE_AllocateTransientObject(key_type, mks,
311 							  &op->key2);
312 			if (res != TEE_SUCCESS)
313 				goto out;
314 		}
315 	}
316 
317 	res = utee_cryp_state_alloc(algorithm, mode, (unsigned long)op->key1,
318 				    (unsigned long)op->key2, &op->state);
319 	if (res != TEE_SUCCESS)
320 		goto out;
321 
322 	/*
323 	 * Initialize digest operations
324 	 * Other multi-stage operations initialized w/ TEE_xxxInit functions
325 	 * Non-applicable on asymmetric operations
326 	 */
327 	if (TEE_ALG_GET_CLASS(algorithm) == TEE_OPERATION_DIGEST) {
328 		res = utee_hash_init(op->state, NULL, 0);
329 		if (res != TEE_SUCCESS)
330 			goto out;
331 		/* v1.1: flags always set for digest operations */
332 		op->info.handleState |= TEE_HANDLE_FLAG_INITIALIZED;
333 	}
334 
335 	op->operationState = TEE_OPERATION_STATE_INITIAL;
336 
337 	*operation = op;
338 
339 out:
340 	if (res != TEE_SUCCESS) {
341 		if (res != TEE_ERROR_OUT_OF_MEMORY &&
342 		    res != TEE_ERROR_NOT_SUPPORTED)
343 			TEE_Panic(res);
344 		if (op) {
345 			if (op->state) {
346 				TEE_FreeOperation(op);
347 			} else {
348 				TEE_Free(op->buffer);
349 				TEE_FreeTransientObject(op->key1);
350 				TEE_FreeTransientObject(op->key2);
351 				TEE_Free(op);
352 			}
353 		}
354 	}
355 
356 	return res;
357 }
358 
359 void TEE_FreeOperation(TEE_OperationHandle operation)
360 {
361 	TEE_Result res;
362 
363 	if (operation == TEE_HANDLE_NULL)
364 		TEE_Panic(0);
365 
366 	/*
367 	 * Note that keys should not be freed here, since they are
368 	 * claimed by the operation they will be freed by
369 	 * utee_cryp_state_free().
370 	 */
371 	res = utee_cryp_state_free(operation->state);
372 	if (res != TEE_SUCCESS)
373 		TEE_Panic(res);
374 
375 	TEE_Free(operation->buffer);
376 	TEE_Free(operation);
377 }
378 
379 void TEE_GetOperationInfo(TEE_OperationHandle operation,
380 			  TEE_OperationInfo *operationInfo)
381 {
382 	if (operation == TEE_HANDLE_NULL)
383 		TEE_Panic(0);
384 
385 	if (!operationInfo)
386 		TEE_Panic(0);
387 
388 	*operationInfo = operation->info;
389 }
390 
391 TEE_Result TEE_GetOperationInfoMultiple(TEE_OperationHandle operation,
392 			  TEE_OperationInfoMultiple *operationInfoMultiple,
393 			  uint32_t *operationSize)
394 {
395 	TEE_Result res = TEE_SUCCESS;
396 	TEE_ObjectInfo key_info1;
397 	TEE_ObjectInfo key_info2;
398 	uint32_t num_of_keys;
399 	size_t n;
400 
401 	if (operation == TEE_HANDLE_NULL) {
402 		res = TEE_ERROR_BAD_PARAMETERS;
403 		goto out;
404 	}
405 
406 	if (!operationInfoMultiple) {
407 		res = TEE_ERROR_BAD_PARAMETERS;
408 		goto out;
409 	}
410 
411 	if (!operationSize) {
412 		res = TEE_ERROR_BAD_PARAMETERS;
413 		goto out;
414 	}
415 
416 	num_of_keys = (*operationSize-sizeof(TEE_OperationInfoMultiple))/
417 			sizeof(TEE_OperationInfoKey);
418 
419 	if (num_of_keys > 2) {
420 		res = TEE_ERROR_BAD_PARAMETERS;
421 		goto out;
422 	}
423 
424 	/* Two keys flag (TEE_ALG_AES_XTS only) */
425 	if ((operation->info.handleState & TEE_HANDLE_FLAG_EXPECT_TWO_KEYS) !=
426 	    0 &&
427 	    (num_of_keys != 2)) {
428 		res = TEE_ERROR_SHORT_BUFFER;
429 		goto out;
430 	}
431 
432 	/* Clear */
433 	for (n = 0; n < num_of_keys; n++) {
434 		operationInfoMultiple->keyInformation[n].keySize = 0;
435 		operationInfoMultiple->keyInformation[n].requiredKeyUsage = 0;
436 	}
437 
438 	if (num_of_keys == 2) {
439 		res = TEE_GetObjectInfo1(operation->key2, &key_info2);
440 		/* Key2 is not a valid handle */
441 		if (res != TEE_SUCCESS)
442 			goto out;
443 
444 		operationInfoMultiple->keyInformation[1].keySize =
445 			key_info2.keySize;
446 		operationInfoMultiple->keyInformation[1].requiredKeyUsage =
447 			operation->info.requiredKeyUsage;
448 	}
449 
450 	if (num_of_keys >= 1) {
451 		res = TEE_GetObjectInfo1(operation->key1, &key_info1);
452 		/* Key1 is not a valid handle */
453 		if (res != TEE_SUCCESS) {
454 			if (num_of_keys == 2) {
455 				operationInfoMultiple->keyInformation[1].
456 							keySize = 0;
457 				operationInfoMultiple->keyInformation[1].
458 							requiredKeyUsage = 0;
459 			}
460 			goto out;
461 		}
462 
463 		operationInfoMultiple->keyInformation[0].keySize =
464 			key_info1.keySize;
465 		operationInfoMultiple->keyInformation[0].requiredKeyUsage =
466 			operation->info.requiredKeyUsage;
467 	}
468 
469 	/* No key */
470 	operationInfoMultiple->algorithm = operation->info.algorithm;
471 	operationInfoMultiple->operationClass = operation->info.operationClass;
472 	operationInfoMultiple->mode = operation->info.mode;
473 	operationInfoMultiple->digestLength = operation->info.digestLength;
474 	operationInfoMultiple->maxKeySize = operation->info.maxKeySize;
475 	operationInfoMultiple->handleState = operation->info.handleState;
476 	operationInfoMultiple->operationState = operation->operationState;
477 	operationInfoMultiple->numberOfKeys = num_of_keys;
478 
479 out:
480 	if (res != TEE_SUCCESS &&
481 	    res != TEE_ERROR_SHORT_BUFFER)
482 		TEE_Panic(res);
483 
484 	return res;
485 }
486 
487 void TEE_ResetOperation(TEE_OperationHandle operation)
488 {
489 	TEE_Result res;
490 
491 	if (operation == TEE_HANDLE_NULL)
492 		TEE_Panic(0);
493 
494 	if (!(operation->info.handleState & TEE_HANDLE_FLAG_KEY_SET))
495 			TEE_Panic(0);
496 
497 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
498 
499 	if (operation->info.operationClass == TEE_OPERATION_DIGEST) {
500 		res = utee_hash_init(operation->state, NULL, 0);
501 		if (res != TEE_SUCCESS)
502 			TEE_Panic(res);
503 		operation->info.handleState |= TEE_HANDLE_FLAG_INITIALIZED;
504 	} else {
505 		operation->info.handleState &= ~TEE_HANDLE_FLAG_INITIALIZED;
506 	}
507 }
508 
509 TEE_Result TEE_SetOperationKey(TEE_OperationHandle operation,
510 			       TEE_ObjectHandle key)
511 {
512 	TEE_Result res;
513 	uint32_t key_size = 0;
514 	TEE_ObjectInfo key_info;
515 
516 	if (operation == TEE_HANDLE_NULL) {
517 		res = TEE_ERROR_BAD_PARAMETERS;
518 		goto out;
519 	}
520 
521 	if (operation->operationState != TEE_OPERATION_STATE_INITIAL) {
522 		res = TEE_ERROR_BAD_PARAMETERS;
523 		goto out;
524 	}
525 
526 	if (key == TEE_HANDLE_NULL) {
527 		/* Operation key cleared */
528 		TEE_ResetTransientObject(operation->key1);
529 		res = TEE_ERROR_BAD_PARAMETERS;
530 		goto out;
531 	}
532 
533 	/* No key for digest operation */
534 	if (operation->info.operationClass == TEE_OPERATION_DIGEST) {
535 		res = TEE_ERROR_BAD_PARAMETERS;
536 		goto out;
537 	}
538 
539 	/* Two keys flag not expected (TEE_ALG_AES_XTS excluded) */
540 	if ((operation->info.handleState & TEE_HANDLE_FLAG_EXPECT_TWO_KEYS) !=
541 	    0) {
542 		res = TEE_ERROR_BAD_PARAMETERS;
543 		goto out;
544 	}
545 
546 	res = TEE_GetObjectInfo1(key, &key_info);
547 	/* Key is not a valid handle */
548 	if (res != TEE_SUCCESS)
549 		goto out;
550 
551 	/* Supplied key has to meet required usage */
552 	if ((key_info.objectUsage & operation->info.requiredKeyUsage) !=
553 	    operation->info.requiredKeyUsage) {
554 		res = TEE_ERROR_BAD_PARAMETERS;
555 		goto out;
556 	}
557 
558 	if (operation->info.maxKeySize < key_info.keySize) {
559 		res = TEE_ERROR_BAD_PARAMETERS;
560 		goto out;
561 	}
562 
563 	key_size = key_info.keySize;
564 
565 	TEE_ResetTransientObject(operation->key1);
566 	operation->info.handleState &= ~TEE_HANDLE_FLAG_KEY_SET;
567 
568 	res = TEE_CopyObjectAttributes1(operation->key1, key);
569 	if (res != TEE_SUCCESS)
570 		goto out;
571 
572 	operation->info.handleState |= TEE_HANDLE_FLAG_KEY_SET;
573 
574 	operation->info.keySize = key_size;
575 
576 out:
577 	if (res != TEE_SUCCESS  &&
578 	    res != TEE_ERROR_CORRUPT_OBJECT &&
579 	    res != TEE_ERROR_STORAGE_NOT_AVAILABLE)
580 		TEE_Panic(res);
581 
582 	return res;
583 }
584 
585 TEE_Result TEE_SetOperationKey2(TEE_OperationHandle operation,
586 				TEE_ObjectHandle key1, TEE_ObjectHandle key2)
587 {
588 	TEE_Result res;
589 	uint32_t key_size = 0;
590 	TEE_ObjectInfo key_info1;
591 	TEE_ObjectInfo key_info2;
592 
593 	if (operation == TEE_HANDLE_NULL) {
594 		res = TEE_ERROR_BAD_PARAMETERS;
595 		goto out;
596 	}
597 
598 	if (operation->operationState != TEE_OPERATION_STATE_INITIAL) {
599 		res = TEE_ERROR_BAD_PARAMETERS;
600 		goto out;
601 	}
602 
603 	/*
604 	 * Key1/Key2 and/or are not initialized and
605 	 * Either both keys are NULL or both are not NULL
606 	 */
607 	if (key1 == TEE_HANDLE_NULL || key2 == TEE_HANDLE_NULL) {
608 		/* Clear operation key1 (if needed) */
609 		if (key1 == TEE_HANDLE_NULL)
610 			TEE_ResetTransientObject(operation->key1);
611 		/* Clear operation key2 (if needed) */
612 		if (key2 == TEE_HANDLE_NULL)
613 			TEE_ResetTransientObject(operation->key2);
614 		res = TEE_ERROR_BAD_PARAMETERS;
615 		goto out;
616 	}
617 
618 	/* No key for digest operation */
619 	if (operation->info.operationClass == TEE_OPERATION_DIGEST) {
620 		res = TEE_ERROR_BAD_PARAMETERS;
621 		goto out;
622 	}
623 
624 	/* Two keys flag expected (TEE_ALG_AES_XTS only) */
625 	if ((operation->info.handleState & TEE_HANDLE_FLAG_EXPECT_TWO_KEYS) ==
626 	    0) {
627 		res = TEE_ERROR_BAD_PARAMETERS;
628 		goto out;
629 	}
630 
631 	res = TEE_GetObjectInfo1(key1, &key_info1);
632 	/* Key1 is not a valid handle */
633 	if (res != TEE_SUCCESS)
634 		goto out;
635 
636 	/* Supplied key has to meet required usage */
637 	if ((key_info1.objectUsage & operation->info.
638 	     requiredKeyUsage) != operation->info.requiredKeyUsage) {
639 		res = TEE_ERROR_BAD_PARAMETERS;
640 		goto out;
641 	}
642 
643 	res = TEE_GetObjectInfo1(key2, &key_info2);
644 	/* Key2 is not a valid handle */
645 	if (res != TEE_SUCCESS) {
646 		if (res == TEE_ERROR_CORRUPT_OBJECT)
647 			res = TEE_ERROR_CORRUPT_OBJECT_2;
648 		goto out;
649 	}
650 
651 	/* Supplied key has to meet required usage */
652 	if ((key_info2.objectUsage & operation->info.
653 	     requiredKeyUsage) != operation->info.requiredKeyUsage) {
654 		res = TEE_ERROR_BAD_PARAMETERS;
655 		goto out;
656 	}
657 
658 	/*
659 	 * AES-XTS (the only multi key algorithm supported, requires the
660 	 * keys to be of equal size.
661 	 */
662 	if (operation->info.algorithm == TEE_ALG_AES_XTS &&
663 	    key_info1.keySize != key_info2.keySize) {
664 		res = TEE_ERROR_BAD_PARAMETERS;
665 		goto out;
666 
667 	}
668 
669 	if (operation->info.maxKeySize < key_info1.keySize) {
670 		res = TEE_ERROR_BAD_PARAMETERS;
671 		goto out;
672 	}
673 
674 	/*
675 	 * Odd that only the size of one key should be reported while
676 	 * size of two key are used when allocating the operation.
677 	 */
678 	key_size = key_info1.keySize;
679 
680 	TEE_ResetTransientObject(operation->key1);
681 	TEE_ResetTransientObject(operation->key2);
682 	operation->info.handleState &= ~TEE_HANDLE_FLAG_KEY_SET;
683 
684 	res = TEE_CopyObjectAttributes1(operation->key1, key1);
685 	if (res != TEE_SUCCESS)
686 		goto out;
687 
688 	res = TEE_CopyObjectAttributes1(operation->key2, key2);
689 	if (res != TEE_SUCCESS) {
690 		if (res == TEE_ERROR_CORRUPT_OBJECT)
691 			res = TEE_ERROR_CORRUPT_OBJECT_2;
692 		goto out;
693 	}
694 
695 	operation->info.handleState |= TEE_HANDLE_FLAG_KEY_SET;
696 
697 	operation->info.keySize = key_size;
698 
699 out:
700 	if (res != TEE_SUCCESS  &&
701 	    res != TEE_ERROR_CORRUPT_OBJECT &&
702 	    res != TEE_ERROR_CORRUPT_OBJECT_2 &&
703 	    res != TEE_ERROR_STORAGE_NOT_AVAILABLE &&
704 	    res != TEE_ERROR_STORAGE_NOT_AVAILABLE_2)
705 		TEE_Panic(res);
706 
707 	return res;
708 }
709 
710 void TEE_CopyOperation(TEE_OperationHandle dst_op, TEE_OperationHandle src_op)
711 {
712 	TEE_Result res;
713 
714 	if (dst_op == TEE_HANDLE_NULL || src_op == TEE_HANDLE_NULL)
715 		TEE_Panic(0);
716 	if (dst_op->info.algorithm != src_op->info.algorithm)
717 		TEE_Panic(0);
718 	if (src_op->info.operationClass != TEE_OPERATION_DIGEST) {
719 		TEE_ObjectHandle key1 = TEE_HANDLE_NULL;
720 		TEE_ObjectHandle key2 = TEE_HANDLE_NULL;
721 
722 		if (src_op->info.handleState & TEE_HANDLE_FLAG_KEY_SET) {
723 			key1 = src_op->key1;
724 			key2 = src_op->key2;
725 		}
726 
727 		if ((src_op->info.handleState &
728 		     TEE_HANDLE_FLAG_EXPECT_TWO_KEYS) == 0) {
729 			TEE_SetOperationKey(dst_op, key1);
730 		} else {
731 			TEE_SetOperationKey2(dst_op, key1, key2);
732 		}
733 	}
734 	dst_op->info.handleState = src_op->info.handleState;
735 	dst_op->info.keySize = src_op->info.keySize;
736 	dst_op->operationState = src_op->operationState;
737 
738 	if (dst_op->buffer_two_blocks != src_op->buffer_two_blocks ||
739 	    dst_op->block_size != src_op->block_size)
740 		TEE_Panic(0);
741 
742 	if (dst_op->buffer != NULL) {
743 		if (src_op->buffer == NULL)
744 			TEE_Panic(0);
745 
746 		memcpy(dst_op->buffer, src_op->buffer, src_op->buffer_offs);
747 		dst_op->buffer_offs = src_op->buffer_offs;
748 	} else if (src_op->buffer != NULL) {
749 		TEE_Panic(0);
750 	}
751 
752 	res = utee_cryp_state_copy(dst_op->state, src_op->state);
753 	if (res != TEE_SUCCESS)
754 		TEE_Panic(res);
755 }
756 
757 /* Cryptographic Operations API - Message Digest Functions */
758 
759 static void init_hash_operation(TEE_OperationHandle operation, const void *IV,
760 				uint32_t IVLen)
761 {
762 	TEE_Result res;
763 
764 	/*
765 	 * Note : IV and IVLen are never used in current implementation
766 	 * This is why coherent values of IV and IVLen are not checked
767 	 */
768 	res = utee_hash_init(operation->state, IV, IVLen);
769 	if (res != TEE_SUCCESS)
770 		TEE_Panic(res);
771 	operation->buffer_offs = 0;
772 	operation->info.handleState |= TEE_HANDLE_FLAG_INITIALIZED;
773 }
774 
775 void TEE_DigestUpdate(TEE_OperationHandle operation,
776 		      const void *chunk, uint32_t chunkSize)
777 {
778 	TEE_Result res = TEE_ERROR_GENERIC;
779 
780 	if (operation == TEE_HANDLE_NULL ||
781 	    operation->info.operationClass != TEE_OPERATION_DIGEST)
782 		TEE_Panic(0);
783 
784 	operation->operationState = TEE_OPERATION_STATE_ACTIVE;
785 
786 	res = utee_hash_update(operation->state, chunk, chunkSize);
787 	if (res != TEE_SUCCESS)
788 		TEE_Panic(res);
789 }
790 
791 TEE_Result TEE_DigestDoFinal(TEE_OperationHandle operation, const void *chunk,
792 			     uint32_t chunkLen, void *hash, uint32_t *hashLen)
793 {
794 	TEE_Result res;
795 	uint64_t hl;
796 
797 	if ((operation == TEE_HANDLE_NULL) ||
798 	    (!chunk && chunkLen) ||
799 	    !hash ||
800 	    !hashLen ||
801 	    (operation->info.operationClass != TEE_OPERATION_DIGEST)) {
802 		res = TEE_ERROR_BAD_PARAMETERS;
803 		goto out;
804 	}
805 
806 	hl = *hashLen;
807 	res = utee_hash_final(operation->state, chunk, chunkLen, hash, &hl);
808 	*hashLen = hl;
809 	if (res != TEE_SUCCESS)
810 		goto out;
811 
812 	/* Reset operation state */
813 	init_hash_operation(operation, NULL, 0);
814 
815 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
816 
817 out:
818 	if (res != TEE_SUCCESS &&
819 	    res != TEE_ERROR_SHORT_BUFFER)
820 		TEE_Panic(res);
821 
822 	return res;
823 }
824 
825 /* Cryptographic Operations API - Symmetric Cipher Functions */
826 
827 void TEE_CipherInit(TEE_OperationHandle operation, const void *IV,
828 		    uint32_t IVLen)
829 {
830 	TEE_Result res;
831 
832 	if (operation == TEE_HANDLE_NULL)
833 		TEE_Panic(0);
834 
835 	if (operation->info.operationClass != TEE_OPERATION_CIPHER)
836 		TEE_Panic(0);
837 
838 	if (!(operation->info.handleState & TEE_HANDLE_FLAG_KEY_SET) ||
839 	    !(operation->key1))
840 		TEE_Panic(0);
841 
842 	if (operation->operationState != TEE_OPERATION_STATE_INITIAL)
843 		TEE_ResetOperation(operation);
844 
845 	operation->operationState = TEE_OPERATION_STATE_ACTIVE;
846 
847 	res = utee_cipher_init(operation->state, IV, IVLen);
848 	if (res != TEE_SUCCESS)
849 		TEE_Panic(res);
850 
851 	operation->buffer_offs = 0;
852 	operation->info.handleState |= TEE_HANDLE_FLAG_INITIALIZED;
853 }
854 
855 static TEE_Result tee_buffer_update(
856 		TEE_OperationHandle op,
857 		TEE_Result(*update_func)(unsigned long state, const void *src,
858 				size_t slen, void *dst, uint64_t *dlen),
859 		const void *src_data, size_t src_len,
860 		void *dest_data, uint64_t *dest_len)
861 {
862 	TEE_Result res;
863 	const uint8_t *src = src_data;
864 	size_t slen = src_len;
865 	uint8_t *dst = dest_data;
866 	size_t dlen = *dest_len;
867 	size_t acc_dlen = 0;
868 	uint64_t tmp_dlen;
869 	size_t l;
870 	size_t buffer_size;
871 	size_t buffer_left;
872 
873 	if (!src) {
874 		if (slen)
875 			TEE_Panic(0);
876 		goto out;
877 	}
878 
879 	if (op->buffer_two_blocks) {
880 		buffer_size = op->block_size * 2;
881 		buffer_left = 1;
882 	} else {
883 		buffer_size = op->block_size;
884 		buffer_left = 0;
885 	}
886 
887 	if (op->buffer_offs > 0) {
888 		/* Fill up complete block */
889 		if (op->buffer_offs < op->block_size)
890 			l = MIN(slen, op->block_size - op->buffer_offs);
891 		else
892 			l = MIN(slen, buffer_size - op->buffer_offs);
893 		memcpy(op->buffer + op->buffer_offs, src, l);
894 		op->buffer_offs += l;
895 		src += l;
896 		slen -= l;
897 		if ((op->buffer_offs % op->block_size) != 0)
898 			goto out;	/* Nothing left to do */
899 	}
900 
901 	/* If we can feed from buffer */
902 	if ((op->buffer_offs > 0) &&
903 	    ((op->buffer_offs + slen) >= (buffer_size + buffer_left))) {
904 		l = ROUNDUP(op->buffer_offs + slen - buffer_size,
905 				op->block_size);
906 		l = MIN(op->buffer_offs, l);
907 		tmp_dlen = dlen;
908 		res = update_func(op->state, op->buffer, l, dst, &tmp_dlen);
909 		if (res != TEE_SUCCESS)
910 			TEE_Panic(res);
911 		dst += tmp_dlen;
912 		dlen -= tmp_dlen;
913 		acc_dlen += tmp_dlen;
914 		op->buffer_offs -= l;
915 		if (op->buffer_offs > 0) {
916 			/*
917 			 * Slen is small enough to be contained in rest buffer.
918 			 */
919 			memcpy(op->buffer, op->buffer + l, buffer_size - l);
920 			memcpy(op->buffer + op->buffer_offs, src, slen);
921 			op->buffer_offs += slen;
922 			goto out;	/* Nothing left to do */
923 		}
924 	}
925 
926 	if (slen >= (buffer_size + buffer_left)) {
927 		/* Buffer is empty, feed as much as possible from src */
928 		if (op->info.algorithm == TEE_ALG_AES_CTS)
929 			l = ROUNDUP(slen - buffer_size, op->block_size);
930 		else
931 			l = ROUNDUP(slen - buffer_size + 1, op->block_size);
932 
933 		tmp_dlen = dlen;
934 		res = update_func(op->state, src, l, dst, &tmp_dlen);
935 		if (res != TEE_SUCCESS)
936 			TEE_Panic(res);
937 		src += l;
938 		slen -= l;
939 		dst += tmp_dlen;
940 		dlen -= tmp_dlen;
941 		acc_dlen += tmp_dlen;
942 	}
943 
944 	/* Slen is small enough to be contained in buffer. */
945 	memcpy(op->buffer + op->buffer_offs, src, slen);
946 	op->buffer_offs += slen;
947 
948 out:
949 	*dest_len = acc_dlen;
950 	return TEE_SUCCESS;
951 }
952 
953 TEE_Result TEE_CipherUpdate(TEE_OperationHandle operation, const void *srcData,
954 			    uint32_t srcLen, void *destData, uint32_t *destLen)
955 {
956 	TEE_Result res;
957 	size_t req_dlen;
958 	uint64_t dl;
959 
960 	if (operation == TEE_HANDLE_NULL ||
961 	    (srcData == NULL && srcLen != 0) ||
962 	    destLen == NULL ||
963 	    (destData == NULL && *destLen != 0)) {
964 		res = TEE_ERROR_BAD_PARAMETERS;
965 		goto out;
966 	}
967 
968 	if (operation->info.operationClass != TEE_OPERATION_CIPHER) {
969 		res = TEE_ERROR_BAD_PARAMETERS;
970 		goto out;
971 	}
972 
973 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
974 		res = TEE_ERROR_BAD_PARAMETERS;
975 		goto out;
976 	}
977 
978 	if (operation->operationState != TEE_OPERATION_STATE_ACTIVE) {
979 		res = TEE_ERROR_BAD_PARAMETERS;
980 		goto out;
981 	}
982 
983 	if (!srcData && !srcLen) {
984 		*destLen = 0;
985 		res = TEE_SUCCESS;
986 		goto out;
987 	}
988 
989 	/* Calculate required dlen */
990 	if (operation->block_size > 1) {
991 		req_dlen = ((operation->buffer_offs + srcLen) /
992 			    operation->block_size) * operation->block_size;
993 	} else {
994 		req_dlen = srcLen;
995 	}
996 	if (operation->buffer_two_blocks) {
997 		if (req_dlen > operation->block_size * 2)
998 			req_dlen -= operation->block_size * 2;
999 		else
1000 			req_dlen = 0;
1001 	}
1002 	/*
1003 	 * Check that required destLen is big enough before starting to feed
1004 	 * data to the algorithm. Errors during feeding of data are fatal as we
1005 	 * can't restore sync with this API.
1006 	 */
1007 	if (*destLen < req_dlen) {
1008 		*destLen = req_dlen;
1009 		res = TEE_ERROR_SHORT_BUFFER;
1010 		goto out;
1011 	}
1012 
1013 	dl = *destLen;
1014 	if (operation->block_size > 1) {
1015 		res = tee_buffer_update(operation, utee_cipher_update, srcData,
1016 					srcLen, destData, &dl);
1017 	} else {
1018 		if (srcLen > 0) {
1019 			res = utee_cipher_update(operation->state, srcData,
1020 						 srcLen, destData, &dl);
1021 		} else {
1022 			res = TEE_SUCCESS;
1023 			dl = 0;
1024 		}
1025 	}
1026 	*destLen = dl;
1027 
1028 out:
1029 	if (res != TEE_SUCCESS &&
1030 	    res != TEE_ERROR_SHORT_BUFFER)
1031 		TEE_Panic(res);
1032 
1033 	return res;
1034 }
1035 
1036 TEE_Result TEE_CipherDoFinal(TEE_OperationHandle operation,
1037 			     const void *srcData, uint32_t srcLen,
1038 			     void *destData, uint32_t *destLen)
1039 {
1040 	TEE_Result res;
1041 	uint8_t *dst = destData;
1042 	size_t acc_dlen = 0;
1043 	uint64_t tmp_dlen;
1044 	size_t req_dlen;
1045 
1046 	if (operation == TEE_HANDLE_NULL ||
1047 	    (srcData == NULL && srcLen != 0) ||
1048 	    destLen == NULL ||
1049 	    (destData == NULL && *destLen != 0)) {
1050 		res = TEE_ERROR_BAD_PARAMETERS;
1051 		goto out;
1052 	}
1053 
1054 	if (operation->info.operationClass != TEE_OPERATION_CIPHER) {
1055 		res = TEE_ERROR_BAD_PARAMETERS;
1056 		goto out;
1057 	}
1058 
1059 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1060 		res = TEE_ERROR_BAD_PARAMETERS;
1061 		goto out;
1062 	}
1063 
1064 	if (operation->operationState != TEE_OPERATION_STATE_ACTIVE) {
1065 		res = TEE_ERROR_BAD_PARAMETERS;
1066 		goto out;
1067 	}
1068 
1069 	/*
1070 	 * Check that the final block doesn't require padding for those
1071 	 * algorithms that requires client to supply padding.
1072 	 */
1073 	if (operation->info.algorithm == TEE_ALG_AES_ECB_NOPAD ||
1074 	    operation->info.algorithm == TEE_ALG_AES_CBC_NOPAD ||
1075 	    operation->info.algorithm == TEE_ALG_DES_ECB_NOPAD ||
1076 	    operation->info.algorithm == TEE_ALG_DES_CBC_NOPAD ||
1077 	    operation->info.algorithm == TEE_ALG_DES3_ECB_NOPAD ||
1078 	    operation->info.algorithm == TEE_ALG_DES3_CBC_NOPAD ||
1079 	    operation->info.algorithm == TEE_ALG_SM4_ECB_NOPAD ||
1080 	    operation->info.algorithm == TEE_ALG_SM4_CBC_NOPAD) {
1081 		if (((operation->buffer_offs + srcLen) % operation->block_size)
1082 		    != 0) {
1083 			res = TEE_ERROR_BAD_PARAMETERS;
1084 			goto out;
1085 		}
1086 	}
1087 
1088 	/*
1089 	 * Check that required destLen is big enough before starting to feed
1090 	 * data to the algorithm. Errors during feeding of data are fatal as we
1091 	 * can't restore sync with this API.
1092 	 */
1093 	if (operation->block_size > 1) {
1094 		req_dlen = operation->buffer_offs + srcLen;
1095 	} else {
1096 		req_dlen = srcLen;
1097 	}
1098 	if (*destLen < req_dlen) {
1099 		*destLen = req_dlen;
1100 		res = TEE_ERROR_SHORT_BUFFER;
1101 		goto out;
1102 	}
1103 
1104 	tmp_dlen = *destLen - acc_dlen;
1105 	if (operation->block_size > 1) {
1106 		res = tee_buffer_update(operation, utee_cipher_update,
1107 					srcData, srcLen, dst, &tmp_dlen);
1108 		if (res != TEE_SUCCESS)
1109 			goto out;
1110 
1111 		dst += tmp_dlen;
1112 		acc_dlen += tmp_dlen;
1113 
1114 		tmp_dlen = *destLen - acc_dlen;
1115 		res = utee_cipher_final(operation->state, operation->buffer,
1116 					operation->buffer_offs, dst, &tmp_dlen);
1117 	} else {
1118 		res = utee_cipher_final(operation->state, srcData,
1119 					srcLen, dst, &tmp_dlen);
1120 	}
1121 	if (res != TEE_SUCCESS)
1122 		goto out;
1123 
1124 	acc_dlen += tmp_dlen;
1125 	*destLen = acc_dlen;
1126 
1127 	operation->info.handleState &= ~TEE_HANDLE_FLAG_INITIALIZED;
1128 
1129 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
1130 
1131 out:
1132 	if (res != TEE_SUCCESS &&
1133 	    res != TEE_ERROR_SHORT_BUFFER)
1134 		TEE_Panic(res);
1135 
1136 	return res;
1137 }
1138 
1139 /* Cryptographic Operations API - MAC Functions */
1140 
1141 void TEE_MACInit(TEE_OperationHandle operation, const void *IV, uint32_t IVLen)
1142 {
1143 	if (operation == TEE_HANDLE_NULL)
1144 		TEE_Panic(0);
1145 
1146 	if (operation->info.operationClass != TEE_OPERATION_MAC)
1147 		TEE_Panic(0);
1148 
1149 	if (!(operation->info.handleState & TEE_HANDLE_FLAG_KEY_SET) ||
1150 	    !(operation->key1))
1151 		TEE_Panic(0);
1152 
1153 	if (operation->operationState != TEE_OPERATION_STATE_INITIAL)
1154 		TEE_ResetOperation(operation);
1155 
1156 	operation->operationState = TEE_OPERATION_STATE_ACTIVE;
1157 
1158 	init_hash_operation(operation, IV, IVLen);
1159 }
1160 
1161 void TEE_MACUpdate(TEE_OperationHandle operation, const void *chunk,
1162 		   uint32_t chunkSize)
1163 {
1164 	TEE_Result res;
1165 
1166 	if (operation == TEE_HANDLE_NULL || (chunk == NULL && chunkSize != 0))
1167 		TEE_Panic(0);
1168 
1169 	if (operation->info.operationClass != TEE_OPERATION_MAC)
1170 		TEE_Panic(0);
1171 
1172 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0)
1173 		TEE_Panic(0);
1174 
1175 	if (operation->operationState != TEE_OPERATION_STATE_ACTIVE)
1176 		TEE_Panic(0);
1177 
1178 	res = utee_hash_update(operation->state, chunk, chunkSize);
1179 	if (res != TEE_SUCCESS)
1180 		TEE_Panic(res);
1181 }
1182 
1183 TEE_Result TEE_MACComputeFinal(TEE_OperationHandle operation,
1184 			       const void *message, uint32_t messageLen,
1185 			       void *mac, uint32_t *macLen)
1186 {
1187 	TEE_Result res;
1188 	uint64_t ml;
1189 
1190 	if (operation == TEE_HANDLE_NULL ||
1191 	    (message == NULL && messageLen != 0) ||
1192 	    mac == NULL ||
1193 	    macLen == NULL) {
1194 		res = TEE_ERROR_BAD_PARAMETERS;
1195 		goto out;
1196 	}
1197 
1198 	if (operation->info.operationClass != TEE_OPERATION_MAC) {
1199 		res = TEE_ERROR_BAD_PARAMETERS;
1200 		goto out;
1201 	}
1202 
1203 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1204 		res = TEE_ERROR_BAD_PARAMETERS;
1205 		goto out;
1206 	}
1207 
1208 	if (operation->operationState != TEE_OPERATION_STATE_ACTIVE) {
1209 		res = TEE_ERROR_BAD_PARAMETERS;
1210 		goto out;
1211 	}
1212 
1213 	ml = *macLen;
1214 	res = utee_hash_final(operation->state, message, messageLen, mac, &ml);
1215 	*macLen = ml;
1216 	if (res != TEE_SUCCESS)
1217 		goto out;
1218 
1219 	operation->info.handleState &= ~TEE_HANDLE_FLAG_INITIALIZED;
1220 
1221 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
1222 
1223 out:
1224 	if (res != TEE_SUCCESS &&
1225 	    res != TEE_ERROR_SHORT_BUFFER)
1226 		TEE_Panic(res);
1227 
1228 	return res;
1229 }
1230 
1231 TEE_Result TEE_MACCompareFinal(TEE_OperationHandle operation,
1232 			       const void *message, uint32_t messageLen,
1233 			       const void *mac, uint32_t macLen)
1234 {
1235 	TEE_Result res;
1236 	uint8_t computed_mac[TEE_MAX_HASH_SIZE];
1237 	uint32_t computed_mac_size = TEE_MAX_HASH_SIZE;
1238 
1239 	if (operation->info.operationClass != TEE_OPERATION_MAC) {
1240 		res = TEE_ERROR_BAD_PARAMETERS;
1241 		goto out;
1242 	}
1243 
1244 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1245 		res = TEE_ERROR_BAD_PARAMETERS;
1246 		goto out;
1247 	}
1248 
1249 	if (operation->operationState != TEE_OPERATION_STATE_ACTIVE) {
1250 		res = TEE_ERROR_BAD_PARAMETERS;
1251 		goto out;
1252 	}
1253 
1254 	res = TEE_MACComputeFinal(operation, message, messageLen, computed_mac,
1255 				  &computed_mac_size);
1256 	if (res != TEE_SUCCESS)
1257 		goto out;
1258 
1259 	if (computed_mac_size != macLen) {
1260 		res = TEE_ERROR_MAC_INVALID;
1261 		goto out;
1262 	}
1263 
1264 	if (consttime_memcmp(mac, computed_mac, computed_mac_size) != 0) {
1265 		res = TEE_ERROR_MAC_INVALID;
1266 		goto out;
1267 	}
1268 
1269 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
1270 
1271 out:
1272 	if (res != TEE_SUCCESS &&
1273 	    res != TEE_ERROR_MAC_INVALID)
1274 		TEE_Panic(res);
1275 
1276 	return res;
1277 }
1278 
1279 /* Cryptographic Operations API - Authenticated Encryption Functions */
1280 
1281 TEE_Result TEE_AEInit(TEE_OperationHandle operation, const void *nonce,
1282 		      uint32_t nonceLen, uint32_t tagLen, uint32_t AADLen,
1283 		      uint32_t payloadLen)
1284 {
1285 	TEE_Result res;
1286 
1287 	if (operation == TEE_HANDLE_NULL || nonce == NULL) {
1288 		res = TEE_ERROR_BAD_PARAMETERS;
1289 		goto out;
1290 	}
1291 
1292 	if (operation->info.operationClass != TEE_OPERATION_AE) {
1293 		res = TEE_ERROR_BAD_PARAMETERS;
1294 		goto out;
1295 	}
1296 
1297 	if (operation->operationState != TEE_OPERATION_STATE_INITIAL) {
1298 		res = TEE_ERROR_BAD_PARAMETERS;
1299 		goto out;
1300 	}
1301 
1302 	/*
1303 	 * AES-CCM tag len is specified by AES-CCM spec and handled in TEE Core
1304 	 * in the implementation. But AES-GCM spec doesn't specify the tag len
1305 	 * according to the same principle so we have to check here instead to
1306 	 * be GP compliant.
1307 	 */
1308 	if (operation->info.algorithm == TEE_ALG_AES_GCM) {
1309 		/*
1310 		 * From GP spec: For AES-GCM, can be 128, 120, 112, 104, or 96
1311 		 */
1312 		if (tagLen < 96 || tagLen > 128 || (tagLen % 8 != 0)) {
1313 			res = TEE_ERROR_NOT_SUPPORTED;
1314 			goto out;
1315 		}
1316 	}
1317 
1318 	res = utee_authenc_init(operation->state, nonce, nonceLen,
1319 				tagLen / 8, AADLen, payloadLen);
1320 	if (res != TEE_SUCCESS)
1321 		goto out;
1322 
1323 	operation->ae_tag_len = tagLen / 8;
1324 	operation->info.handleState |= TEE_HANDLE_FLAG_INITIALIZED;
1325 
1326 out:
1327 	if (res != TEE_SUCCESS &&
1328 	    res != TEE_ERROR_NOT_SUPPORTED)
1329 			TEE_Panic(res);
1330 
1331 	return res;
1332 }
1333 
1334 void TEE_AEUpdateAAD(TEE_OperationHandle operation, const void *AADdata,
1335 		     uint32_t AADdataLen)
1336 {
1337 	TEE_Result res;
1338 
1339 	if (operation == TEE_HANDLE_NULL ||
1340 	    (AADdata == NULL && AADdataLen != 0))
1341 		TEE_Panic(0);
1342 
1343 	if (operation->info.operationClass != TEE_OPERATION_AE)
1344 		TEE_Panic(0);
1345 
1346 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0)
1347 		TEE_Panic(0);
1348 
1349 	res = utee_authenc_update_aad(operation->state, AADdata, AADdataLen);
1350 
1351 	operation->operationState = TEE_OPERATION_STATE_ACTIVE;
1352 
1353 	if (res != TEE_SUCCESS)
1354 		TEE_Panic(res);
1355 }
1356 
1357 TEE_Result TEE_AEUpdate(TEE_OperationHandle operation, const void *srcData,
1358 			uint32_t srcLen, void *destData, uint32_t *destLen)
1359 {
1360 	TEE_Result res;
1361 	size_t req_dlen;
1362 	uint64_t dl;
1363 
1364 	if (operation == TEE_HANDLE_NULL ||
1365 	    (srcData == NULL && srcLen != 0) ||
1366 	    destLen == NULL ||
1367 	    (destData == NULL && *destLen != 0)) {
1368 		res = TEE_ERROR_BAD_PARAMETERS;
1369 		goto out;
1370 	}
1371 
1372 	if (operation->info.operationClass != TEE_OPERATION_AE) {
1373 		res = TEE_ERROR_BAD_PARAMETERS;
1374 		goto out;
1375 	}
1376 
1377 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1378 		res = TEE_ERROR_BAD_PARAMETERS;
1379 		goto out;
1380 	}
1381 
1382 	if (!srcData && !srcLen) {
1383 		*destLen = 0;
1384 		res = TEE_SUCCESS;
1385 		goto out;
1386 	}
1387 
1388 	/*
1389 	 * Check that required destLen is big enough before starting to feed
1390 	 * data to the algorithm. Errors during feeding of data are fatal as we
1391 	 * can't restore sync with this API.
1392 	 */
1393 	if (operation->block_size > 1) {
1394 		req_dlen = ROUNDDOWN(operation->buffer_offs + srcLen,
1395 				     operation->block_size);
1396 	} else {
1397 		req_dlen = srcLen;
1398 	}
1399 
1400 	if (*destLen < req_dlen) {
1401 		*destLen = req_dlen;
1402 		res = TEE_ERROR_SHORT_BUFFER;
1403 		goto out;
1404 	}
1405 
1406 	dl = *destLen;
1407 	if (operation->block_size > 1) {
1408 		res = tee_buffer_update(operation, utee_authenc_update_payload,
1409 					srcData, srcLen, destData, &dl);
1410 	} else {
1411 		if (srcLen > 0) {
1412 			res = utee_authenc_update_payload(operation->state,
1413 							  srcData, srcLen,
1414 							  destData, &dl);
1415 		} else {
1416 			dl = 0;
1417 			res = TEE_SUCCESS;
1418 		}
1419 	}
1420 	if (res != TEE_SUCCESS)
1421 		goto out;
1422 
1423 	*destLen = dl;
1424 
1425 	operation->operationState = TEE_OPERATION_STATE_ACTIVE;
1426 
1427 out:
1428 	if (res != TEE_SUCCESS &&
1429 	    res != TEE_ERROR_SHORT_BUFFER)
1430 			TEE_Panic(res);
1431 
1432 	return res;
1433 }
1434 
1435 TEE_Result TEE_AEEncryptFinal(TEE_OperationHandle operation,
1436 			      const void *srcData, uint32_t srcLen,
1437 			      void *destData, uint32_t *destLen, void *tag,
1438 			      uint32_t *tagLen)
1439 {
1440 	TEE_Result res;
1441 	uint8_t *dst = destData;
1442 	size_t acc_dlen = 0;
1443 	uint64_t tmp_dlen;
1444 	size_t req_dlen;
1445 	uint64_t tl;
1446 
1447 	if (operation == TEE_HANDLE_NULL ||
1448 	    (srcData == NULL && srcLen != 0) ||
1449 	    destLen == NULL ||
1450 	    (destData == NULL && *destLen != 0) ||
1451 	    tag == NULL || tagLen == NULL) {
1452 		res = TEE_ERROR_BAD_PARAMETERS;
1453 		goto out;
1454 	}
1455 
1456 	if (operation->info.operationClass != TEE_OPERATION_AE) {
1457 		res = TEE_ERROR_BAD_PARAMETERS;
1458 		goto out;
1459 	}
1460 
1461 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1462 		res = TEE_ERROR_BAD_PARAMETERS;
1463 		goto out;
1464 	}
1465 
1466 	/*
1467 	 * Check that required destLen is big enough before starting to feed
1468 	 * data to the algorithm. Errors during feeding of data are fatal as we
1469 	 * can't restore sync with this API.
1470 	 *
1471 	 * Need to check this before update_payload since sync would be lost if
1472 	 * we return short buffer after that.
1473 	 */
1474 	res = TEE_ERROR_GENERIC;
1475 
1476 	req_dlen = operation->buffer_offs + srcLen;
1477 	if (*destLen < req_dlen) {
1478 		*destLen = req_dlen;
1479 		res = TEE_ERROR_SHORT_BUFFER;
1480 	}
1481 
1482 	if (*tagLen < operation->ae_tag_len) {
1483 		*tagLen = operation->ae_tag_len;
1484 		res = TEE_ERROR_SHORT_BUFFER;
1485 	}
1486 
1487 	if (res == TEE_ERROR_SHORT_BUFFER)
1488 		goto out;
1489 
1490 	tl = *tagLen;
1491 	tmp_dlen = *destLen - acc_dlen;
1492 	if (operation->block_size > 1) {
1493 		res = tee_buffer_update(operation, utee_authenc_update_payload,
1494 					srcData, srcLen, dst, &tmp_dlen);
1495 		if (res != TEE_SUCCESS)
1496 			goto out;
1497 
1498 		dst += tmp_dlen;
1499 		acc_dlen += tmp_dlen;
1500 
1501 		tmp_dlen = *destLen - acc_dlen;
1502 		res = utee_authenc_enc_final(operation->state,
1503 					     operation->buffer,
1504 					     operation->buffer_offs, dst,
1505 					     &tmp_dlen, tag, &tl);
1506 	} else {
1507 		res = utee_authenc_enc_final(operation->state, srcData,
1508 					     srcLen, dst, &tmp_dlen,
1509 					     tag, &tl);
1510 	}
1511 	*tagLen = tl;
1512 	if (res != TEE_SUCCESS)
1513 		goto out;
1514 
1515 	acc_dlen += tmp_dlen;
1516 	*destLen = acc_dlen;
1517 
1518 	operation->info.handleState &= ~TEE_HANDLE_FLAG_INITIALIZED;
1519 
1520 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
1521 
1522 out:
1523 	if (res != TEE_SUCCESS &&
1524 	    res != TEE_ERROR_SHORT_BUFFER)
1525 			TEE_Panic(res);
1526 
1527 	return res;
1528 }
1529 
1530 TEE_Result TEE_AEDecryptFinal(TEE_OperationHandle operation,
1531 			      const void *srcData, uint32_t srcLen,
1532 			      void *destData, uint32_t *destLen, void *tag,
1533 			      uint32_t tagLen)
1534 {
1535 	TEE_Result res;
1536 	uint8_t *dst = destData;
1537 	size_t acc_dlen = 0;
1538 	uint64_t tmp_dlen;
1539 	size_t req_dlen;
1540 
1541 	if (operation == TEE_HANDLE_NULL ||
1542 	    (srcData == NULL && srcLen != 0) ||
1543 	    destLen == NULL ||
1544 	    (destData == NULL && *destLen != 0) ||
1545 	    (tag == NULL && tagLen != 0)) {
1546 		res = TEE_ERROR_BAD_PARAMETERS;
1547 		goto out;
1548 	}
1549 
1550 	if (operation->info.operationClass != TEE_OPERATION_AE) {
1551 		res = TEE_ERROR_BAD_PARAMETERS;
1552 		goto out;
1553 	}
1554 
1555 	if ((operation->info.handleState & TEE_HANDLE_FLAG_INITIALIZED) == 0) {
1556 		res = TEE_ERROR_BAD_PARAMETERS;
1557 		goto out;
1558 	}
1559 
1560 	/*
1561 	 * Check that required destLen is big enough before starting to feed
1562 	 * data to the algorithm. Errors during feeding of data are fatal as we
1563 	 * can't restore sync with this API.
1564 	 */
1565 	req_dlen = operation->buffer_offs + srcLen;
1566 	if (*destLen < req_dlen) {
1567 		*destLen = req_dlen;
1568 		res = TEE_ERROR_SHORT_BUFFER;
1569 		goto out;
1570 	}
1571 
1572 	tmp_dlen = *destLen - acc_dlen;
1573 	if (operation->block_size > 1) {
1574 		res = tee_buffer_update(operation, utee_authenc_update_payload,
1575 					srcData, srcLen, dst, &tmp_dlen);
1576 		if (res != TEE_SUCCESS)
1577 			goto out;
1578 
1579 		dst += tmp_dlen;
1580 		acc_dlen += tmp_dlen;
1581 
1582 		tmp_dlen = *destLen - acc_dlen;
1583 		res = utee_authenc_dec_final(operation->state,
1584 					     operation->buffer,
1585 					     operation->buffer_offs, dst,
1586 					     &tmp_dlen, tag, tagLen);
1587 	} else {
1588 		res = utee_authenc_dec_final(operation->state, srcData,
1589 					     srcLen, dst, &tmp_dlen,
1590 					     tag, tagLen);
1591 	}
1592 	if (res != TEE_SUCCESS)
1593 		goto out;
1594 
1595 	/* Supplied tagLen should match what we initiated with */
1596 	if (tagLen != operation->ae_tag_len)
1597 		res = TEE_ERROR_MAC_INVALID;
1598 
1599 	acc_dlen += tmp_dlen;
1600 	*destLen = acc_dlen;
1601 
1602 	operation->info.handleState &= ~TEE_HANDLE_FLAG_INITIALIZED;
1603 
1604 	operation->operationState = TEE_OPERATION_STATE_INITIAL;
1605 
1606 out:
1607 	if (res != TEE_SUCCESS &&
1608 	    res != TEE_ERROR_SHORT_BUFFER &&
1609 	    res != TEE_ERROR_MAC_INVALID)
1610 			TEE_Panic(res);
1611 
1612 	return res;
1613 }
1614 
1615 /* Cryptographic Operations API - Asymmetric Functions */
1616 
1617 TEE_Result TEE_AsymmetricEncrypt(TEE_OperationHandle operation,
1618 				 const TEE_Attribute *params,
1619 				 uint32_t paramCount, const void *srcData,
1620 				 uint32_t srcLen, void *destData,
1621 				 uint32_t *destLen)
1622 {
1623 	TEE_Result res;
1624 	struct utee_attribute ua[paramCount];
1625 	uint64_t dl;
1626 
1627 	if (operation == TEE_HANDLE_NULL || (srcData == NULL && srcLen != 0) ||
1628 	    destLen == NULL || (destData == NULL && *destLen != 0))
1629 		TEE_Panic(0);
1630 	if (params == NULL && paramCount != 0)
1631 		TEE_Panic(0);
1632 	if (!operation->key1)
1633 		TEE_Panic(0);
1634 	if (operation->info.operationClass != TEE_OPERATION_ASYMMETRIC_CIPHER)
1635 		TEE_Panic(0);
1636 	if (operation->info.mode != TEE_MODE_ENCRYPT)
1637 		TEE_Panic(0);
1638 
1639 	__utee_from_attr(ua, params, paramCount);
1640 	dl = *destLen;
1641 	res = utee_asymm_operate(operation->state, ua, paramCount, srcData,
1642 				 srcLen, destData, &dl);
1643 	*destLen = dl;
1644 
1645 	if (res != TEE_SUCCESS &&
1646 	    res != TEE_ERROR_SHORT_BUFFER &&
1647 	    res != TEE_ERROR_BAD_PARAMETERS)
1648 		TEE_Panic(res);
1649 
1650 	return res;
1651 }
1652 
1653 TEE_Result TEE_AsymmetricDecrypt(TEE_OperationHandle operation,
1654 				 const TEE_Attribute *params,
1655 				 uint32_t paramCount, const void *srcData,
1656 				 uint32_t srcLen, void *destData,
1657 				 uint32_t *destLen)
1658 {
1659 	TEE_Result res;
1660 	struct utee_attribute ua[paramCount];
1661 	uint64_t dl;
1662 
1663 	if (operation == TEE_HANDLE_NULL || (srcData == NULL && srcLen != 0) ||
1664 	    destLen == NULL || (destData == NULL && *destLen != 0))
1665 		TEE_Panic(0);
1666 	if (params == NULL && paramCount != 0)
1667 		TEE_Panic(0);
1668 	if (!operation->key1)
1669 		TEE_Panic(0);
1670 	if (operation->info.operationClass != TEE_OPERATION_ASYMMETRIC_CIPHER)
1671 		TEE_Panic(0);
1672 	if (operation->info.mode != TEE_MODE_DECRYPT)
1673 		TEE_Panic(0);
1674 
1675 	__utee_from_attr(ua, params, paramCount);
1676 	dl = *destLen;
1677 	res = utee_asymm_operate(operation->state, ua, paramCount, srcData,
1678 				 srcLen, destData, &dl);
1679 	*destLen = dl;
1680 
1681 	if (res != TEE_SUCCESS &&
1682 	    res != TEE_ERROR_SHORT_BUFFER &&
1683 	    res != TEE_ERROR_BAD_PARAMETERS)
1684 		TEE_Panic(res);
1685 
1686 	return res;
1687 }
1688 
1689 TEE_Result TEE_AsymmetricSignDigest(TEE_OperationHandle operation,
1690 				    const TEE_Attribute *params,
1691 				    uint32_t paramCount, const void *digest,
1692 				    uint32_t digestLen, void *signature,
1693 				    uint32_t *signatureLen)
1694 {
1695 	TEE_Result res;
1696 	struct utee_attribute ua[paramCount];
1697 	uint64_t sl;
1698 
1699 	if (operation == TEE_HANDLE_NULL ||
1700 	    (digest == NULL && digestLen != 0) ||
1701 	    signature == NULL || signatureLen == NULL)
1702 		TEE_Panic(0);
1703 	if (params == NULL && paramCount != 0)
1704 		TEE_Panic(0);
1705 	if (!operation->key1)
1706 		TEE_Panic(0);
1707 	if (operation->info.operationClass !=
1708 	    TEE_OPERATION_ASYMMETRIC_SIGNATURE)
1709 		TEE_Panic(0);
1710 	if (operation->info.mode != TEE_MODE_SIGN)
1711 		TEE_Panic(0);
1712 
1713 	__utee_from_attr(ua, params, paramCount);
1714 	sl = *signatureLen;
1715 	res = utee_asymm_operate(operation->state, ua, paramCount, digest,
1716 				 digestLen, signature, &sl);
1717 	*signatureLen = sl;
1718 
1719 	if (res != TEE_SUCCESS && res != TEE_ERROR_SHORT_BUFFER)
1720 		TEE_Panic(res);
1721 
1722 	return res;
1723 }
1724 
1725 TEE_Result TEE_AsymmetricVerifyDigest(TEE_OperationHandle operation,
1726 				      const TEE_Attribute *params,
1727 				      uint32_t paramCount, const void *digest,
1728 				      uint32_t digestLen,
1729 				      const void *signature,
1730 				      uint32_t signatureLen)
1731 {
1732 	TEE_Result res;
1733 	struct utee_attribute ua[paramCount];
1734 
1735 	if (operation == TEE_HANDLE_NULL ||
1736 	    (digest == NULL && digestLen != 0) ||
1737 	    (signature == NULL && signatureLen != 0))
1738 		TEE_Panic(0);
1739 	if (params == NULL && paramCount != 0)
1740 		TEE_Panic(0);
1741 	if (!operation->key1)
1742 		TEE_Panic(0);
1743 	if (operation->info.operationClass !=
1744 	    TEE_OPERATION_ASYMMETRIC_SIGNATURE)
1745 		TEE_Panic(0);
1746 	if (operation->info.mode != TEE_MODE_VERIFY)
1747 		TEE_Panic(0);
1748 
1749 	__utee_from_attr(ua, params, paramCount);
1750 	res = utee_asymm_verify(operation->state, ua, paramCount, digest,
1751 				digestLen, signature, signatureLen);
1752 
1753 	if (res != TEE_SUCCESS && res != TEE_ERROR_SIGNATURE_INVALID)
1754 		TEE_Panic(res);
1755 
1756 	return res;
1757 }
1758 
1759 /* Cryptographic Operations API - Key Derivation Functions */
1760 
1761 void TEE_DeriveKey(TEE_OperationHandle operation,
1762 		   const TEE_Attribute *params, uint32_t paramCount,
1763 		   TEE_ObjectHandle derivedKey)
1764 {
1765 	TEE_Result res;
1766 	TEE_ObjectInfo key_info;
1767 	struct utee_attribute ua[paramCount];
1768 
1769 	if (operation == TEE_HANDLE_NULL || derivedKey == 0)
1770 		TEE_Panic(0);
1771 	if (params == NULL && paramCount != 0)
1772 		TEE_Panic(0);
1773 	if (TEE_ALG_GET_CLASS(operation->info.algorithm) !=
1774 	    TEE_OPERATION_KEY_DERIVATION)
1775 		TEE_Panic(0);
1776 
1777 	if (operation->info.operationClass != TEE_OPERATION_KEY_DERIVATION)
1778 		TEE_Panic(0);
1779 	if (!operation->key1)
1780 		TEE_Panic(0);
1781 	if (operation->info.mode != TEE_MODE_DERIVE)
1782 		TEE_Panic(0);
1783 	if ((operation->info.handleState & TEE_HANDLE_FLAG_KEY_SET) == 0)
1784 		TEE_Panic(0);
1785 
1786 	res = utee_cryp_obj_get_info((unsigned long)derivedKey, &key_info);
1787 	if (res != TEE_SUCCESS)
1788 		TEE_Panic(res);
1789 
1790 	if (key_info.objectType != TEE_TYPE_GENERIC_SECRET)
1791 		TEE_Panic(0);
1792 	if ((key_info.handleFlags & TEE_HANDLE_FLAG_INITIALIZED) != 0)
1793 		TEE_Panic(0);
1794 
1795 	__utee_from_attr(ua, params, paramCount);
1796 	res = utee_cryp_derive_key(operation->state, ua, paramCount,
1797 				   (unsigned long)derivedKey);
1798 	if (res != TEE_SUCCESS)
1799 		TEE_Panic(res);
1800 }
1801 
1802 /* Cryptographic Operations API - Random Number Generation Functions */
1803 
1804 void TEE_GenerateRandom(void *randomBuffer, uint32_t randomBufferLen)
1805 {
1806 	TEE_Result res;
1807 
1808 	res = utee_cryp_random_number_generate(randomBuffer, randomBufferLen);
1809 	if (res != TEE_SUCCESS)
1810 		TEE_Panic(res);
1811 }
1812 
1813 int rand(void)
1814 {
1815 	int rc;
1816 
1817 	TEE_GenerateRandom(&rc, sizeof(rc));
1818 
1819 	/*
1820 	 * RAND_MAX is the larges int, INT_MAX which is all bits but the
1821 	 * highest bit set.
1822 	 */
1823 	return rc & RAND_MAX;
1824 }
1825