aes_rval aes_decrypt_key(const unsigned char *key, int key_len, aes_decrypt_ctx cx[1])
{
switch(key_len)
{
#if defined( AES_ERR_CHK )
case 16: case 128: return aes_decrypt_key128(key, cx);
case 24: case 192: return aes_decrypt_key192(key, cx);
case 32: case 256: return aes_decrypt_key256(key, cx);
default: return aes_error;
#else
case 16: case 128: aes_decrypt_key128(key, cx); return;
case 24: case 192: aes_decrypt_key192(key, cx); return;
case 32: case 256: aes_decrypt_key256(key, cx); return;
#endif
}
}
aes_rval aes_decrypt_key(const void *in_key, int key_len, aes_decrypt_ctx cx[1])
{
switch(key_len)
{
#ifdef AES_ERR_CHK
case 16: case 128: return aes_decrypt_key128(in_key, cx);
case 24: case 192: return aes_decrypt_key192(in_key, cx);
case 32: case 256: return aes_decrypt_key256(in_key, cx);
default: return aes_error;
#else
case 16: case 128: aes_decrypt_key128(in_key, cx); return;
case 24: case 192: aes_decrypt_key192(in_key, cx); return;
case 32: case 256: aes_decrypt_key256(in_key, cx); return;
#endif
}
}
AES_RETURN aes_decrypt_key(const unsigned char *key, int key_len, aes_decrypt_ctx cx[1])
{
switch(key_len)
{
case 16: case 128: return aes_decrypt_key128(key, cx);
case 24: case 192: return aes_decrypt_key192(key, cx);
case 32: case 256: return aes_decrypt_key256(key, cx);
default: return EXIT_FAILURE;
}
}
/*
* Expand the cipher key into the decryption key schedule.
*
* Return the number of rounds for the given cipher key size.
* The size of the key schedule depends on the number of rounds
* (which can be computed from the size of the key), i.e. 4 * (Nr + 1).
*
* Parameters:
* rk AES key schedule 32-bit array to be initialized
* cipherKey User key
* keyBits AES key size (128, 192, or 256 bits)
*/
int
rijndael_key_setup_dec_amd64(uint32_t rk[], const uint32_t cipherKey[],
int keyBits)
{
switch (keyBits) {
case 128:
aes_decrypt_key128((unsigned char *)&cipherKey[0], rk);
return (10);
case 192:
aes_decrypt_key192((unsigned char *)&cipherKey[0], rk);
return (12);
case 256:
aes_decrypt_key256((unsigned char *)&cipherKey[0], rk);
return (14);
default: /* should never get here */
break;
}
return (0);
}
static bool
aes_operation(bool encrypt, const uint8_t *kek, size_t kek_len, uint8_t *block)
{
uint64_t iv[2] = { 0 };
if (encrypt) {
aes_encrypt_ctx encrypt_ctx[1];
switch(kek_len) {
#if AES128_KEK
case 16: aes_encrypt_key128(kek, encrypt_ctx); break;
#endif
#if AES192_KEK
case 24: aes_encrypt_key192(kek, encrypt_ctx); break;
#endif
#if AES256_KEK
case 32: aes_encrypt_key256(kek, encrypt_ctx); break;
#endif
default: return false;
}
aes_encrypt_cbc(block, (uint8_t*)iv, 1, block, encrypt_ctx);
} else {
aes_decrypt_ctx decrypt_ctx[1];
switch(kek_len) {
#if AES128_KEK
case 16: aes_decrypt_key128(kek, decrypt_ctx); break;
#endif
#if AES192_KEK
case 24: aes_decrypt_key192(kek, decrypt_ctx); break;
#endif
#if AES256_KEK
case 32: aes_decrypt_key256(kek, decrypt_ctx); break;
#endif
default: return false;
}
aes_decrypt_cbc(block, (uint8_t*)iv, 1, block, decrypt_ctx);
}
return true;
}