| // SPDX-License-Identifier: BSD-2-Clause |
| /* LibTomCrypt, modular cryptographic library -- Tom St Denis |
| * |
| * LibTomCrypt is a library that provides various cryptographic |
| * algorithms in a highly modular and flexible manner. |
| * |
| * The library is free for all purposes without any express |
| * guarantee it works. |
| */ |
| #include "tomcrypt_private.h" |
| |
| /** |
| @file ecb_decrypt.c |
| ECB implementation, decrypt a block, Tom St Denis |
| */ |
| |
| #ifdef LTC_ECB_MODE |
| |
| /** |
| ECB decrypt |
| @param ct Ciphertext |
| @param pt [out] Plaintext |
| @param len The number of octets to process (must be multiple of the cipher block size) |
| @param ecb ECB state |
| @return CRYPT_OK if successful |
| */ |
| int ecb_decrypt(const unsigned char *ct, unsigned char *pt, unsigned long len, symmetric_ECB *ecb) |
| { |
| int err; |
| LTC_ARGCHK(pt != NULL); |
| LTC_ARGCHK(ct != NULL); |
| LTC_ARGCHK(ecb != NULL); |
| if ((err = cipher_is_valid(ecb->cipher)) != CRYPT_OK) { |
| return err; |
| } |
| if (len % cipher_descriptor[ecb->cipher]->block_length) { |
| return CRYPT_INVALID_ARG; |
| } |
| |
| /* check for accel */ |
| if (cipher_descriptor[ecb->cipher]->accel_ecb_decrypt != NULL) { |
| return cipher_descriptor[ecb->cipher]->accel_ecb_decrypt(ct, pt, len / cipher_descriptor[ecb->cipher]->block_length, &ecb->key); |
| } |
| while (len) { |
| if ((err = cipher_descriptor[ecb->cipher]->ecb_decrypt(ct, pt, &ecb->key)) != CRYPT_OK) { |
| return err; |
| } |
| pt += cipher_descriptor[ecb->cipher]->block_length; |
| ct += cipher_descriptor[ecb->cipher]->block_length; |
| len -= cipher_descriptor[ecb->cipher]->block_length; |
| } |
| return CRYPT_OK; |
| } |
| |
| #endif |
| |
| /* ref: $Format:%D$ */ |
| /* git commit: $Format:%H$ */ |
| /* commit time: $Format:%ai$ */ |