36 lines
961 B
C
36 lines
961 B
C
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#include "aes256.h"
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void cbc256_encrypt(uint8_t* in, size_t length, uint8_t* key, uint8_t* iv, uint8_t* out) {
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uint32_t expandedKey[EXPANDED_KEY_SIZE];
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uint32_t i, j;
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uint8_t* currentIv = iv;
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aes256_set_encryption_key(key, expandedKey);
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for (i = 0; i < length; i += AES_BLOCK_SIZE) {
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for (j = 0; j < AES_BLOCK_SIZE; ++j)
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out[i + j] = in[i + j] ^ currentIv[j];
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aes256_encrypt(&out[i], &out[i], expandedKey);
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currentIv = &out[i];
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}
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}
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void cbc256_decrypt(uint8_t* in, size_t length, uint8_t* key, uint8_t* iv, uint8_t* out) {
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uint32_t expandedKey[EXPANDED_KEY_SIZE];
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uint32_t i, j;
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uint8_t* currentIv = iv;
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aes256_set_decryption_key(key, expandedKey);
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for (i = 0; i < length; i += AES_BLOCK_SIZE) {
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aes256_decrypt(&in[i], &out[i], expandedKey);
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for (j = 0; j < AES_BLOCK_SIZE; ++j)
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out[i + j] ^= currentIv[j];
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currentIv = &in[i];
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}
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}
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