1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2014-2019, Linaro Limited 4 */ 5 6 #include <assert.h> 7 #include <crypto/crypto.h> 8 #include <crypto/crypto_impl.h> 9 #include <stdlib.h> 10 #include <tee_api_types.h> 11 #include <tomcrypt_private.h> 12 #include <util.h> 13 14 struct ltc_ctr_ctx { 15 struct crypto_cipher_ctx ctx; 16 int cipher_idx; 17 int (*update)(const unsigned char *src, unsigned char *dst, 18 unsigned long len, symmetric_CTR *ctr); 19 symmetric_CTR state; 20 }; 21 22 static const struct crypto_cipher_ops ltc_ctr_ops; 23 24 static struct ltc_ctr_ctx *to_ctr_ctx(struct crypto_cipher_ctx *ctx) 25 { 26 assert(ctx && ctx->ops == <c_ctr_ops); 27 28 return container_of(ctx, struct ltc_ctr_ctx, ctx); 29 } 30 31 static TEE_Result ltc_ctr_init(struct crypto_cipher_ctx *ctx, 32 TEE_OperationMode mode, const uint8_t *key1, 33 size_t key1_len, const uint8_t *key2 __unused, 34 size_t key2_len __unused, 35 const uint8_t *iv __unused, 36 size_t iv_len __unused) 37 { 38 struct ltc_ctr_ctx *c = to_ctr_ctx(ctx); 39 40 if ((int)iv_len != cipher_descriptor[c->cipher_idx]->block_length) 41 return TEE_ERROR_BAD_PARAMETERS; 42 43 if (mode == TEE_MODE_ENCRYPT) 44 c->update = ctr_encrypt; 45 else 46 c->update = ctr_decrypt; 47 48 if (ctr_start(c->cipher_idx, iv, key1, key1_len, 0, 49 CTR_COUNTER_BIG_ENDIAN, &c->state) == CRYPT_OK) 50 return TEE_SUCCESS; 51 else 52 return TEE_ERROR_BAD_STATE; 53 } 54 55 static TEE_Result ltc_ctr_update(struct crypto_cipher_ctx *ctx, 56 bool last_block __unused, 57 const uint8_t *data, size_t len, uint8_t *dst) 58 { 59 struct ltc_ctr_ctx *c = to_ctr_ctx(ctx); 60 61 if (c->update && c->update(data, dst, len, &c->state) == CRYPT_OK) 62 return TEE_SUCCESS; 63 else 64 return TEE_ERROR_BAD_STATE; 65 } 66 67 static void ltc_ctr_final(struct crypto_cipher_ctx *ctx) 68 { 69 ctr_done(&to_ctr_ctx(ctx)->state); 70 } 71 72 static void ltc_ctr_free_ctx(struct crypto_cipher_ctx *ctx) 73 { 74 free(to_ctr_ctx(ctx)); 75 } 76 77 static void ltc_ctr_copy_state(struct crypto_cipher_ctx *dst_ctx, 78 struct crypto_cipher_ctx *src_ctx) 79 { 80 struct ltc_ctr_ctx *src = to_ctr_ctx(src_ctx); 81 struct ltc_ctr_ctx *dst = to_ctr_ctx(dst_ctx); 82 83 assert(src->cipher_idx == dst->cipher_idx); 84 dst->update = src->update; 85 dst->state = src->state; 86 } 87 88 static const struct crypto_cipher_ops ltc_ctr_ops = { 89 .init = ltc_ctr_init, 90 .update = ltc_ctr_update, 91 .final = ltc_ctr_final, 92 .free_ctx = ltc_ctr_free_ctx, 93 .copy_state = ltc_ctr_copy_state, 94 }; 95 96 TEE_Result crypto_aes_ctr_alloc_ctx(struct crypto_cipher_ctx **ctx_ret) 97 { 98 struct ltc_ctr_ctx *c = NULL; 99 int cipher_idx = find_cipher("aes"); 100 101 if (cipher_idx < 0) 102 return TEE_ERROR_NOT_SUPPORTED; 103 104 c = calloc(1, sizeof(*c)); 105 if (!c) 106 return TEE_ERROR_OUT_OF_MEMORY; 107 108 c->ctx.ops = <c_ctr_ops; 109 c->cipher_idx = cipher_idx; 110 *ctx_ret = &c->ctx; 111 112 return TEE_SUCCESS; 113 } 114