int decrypt_final(riv_context_t* ctx,
const unsigned char* ciphertext,
const unsigned long long ciphertext_length,
const unsigned char* header,
const unsigned long long header_length,
const unsigned char tag[TAGLEN],
unsigned char* plaintext)
{
ALIGN(16) uint8_t iv[TAGLEN];
ALIGN(16) uint8_t iv_prime[TAGLEN];
clhash(&(ctx->prf_context),
header, header_length, DOMAIN_1, ciphertext, ciphertext_length, iv);
cdms(iv, iv, ctx->expanded_key);
xor_bytes(iv, iv, tag, TAGLEN);
cdms(iv_prime, iv, ctx->expanded_key);
sct_mode(ctx, iv_prime, (const __m128i*)ciphertext,
ciphertext_length, (__m128i*)plaintext);
clhash(&(ctx->prf_context),
header, header_length, DOMAIN_0, plaintext, ciphertext_length, iv_prime);
cdms(iv_prime, iv_prime, ctx->expanded_key);
return (_mm_testc_si128(load(iv), load(iv_prime)) - 1)
| (_mm_testc_si128(load((iv+BLOCKLEN)), load((iv_prime+BLOCKLEN))) - 1);
}
void encrypt_final(riv_context_t* ctx,
const unsigned char* plaintext,
const unsigned long long plaintext_length,
const unsigned char* header,
const unsigned long long header_length,
unsigned char* ciphertext,
unsigned char tag[TAGLEN])
{
ALIGN(16) uint8_t iv[TAGLEN];
ALIGN(16) uint8_t s[TAGLEN];
clhash(&(ctx->prf_context), header, header_length, DOMAIN_0,
plaintext, plaintext_length, iv);
cdms(iv, iv, ctx->expanded_key);
ALIGN(16) uint8_t iv_prime[TAGLEN];
cdms(iv_prime, iv, ctx->expanded_key);
sct_mode(ctx, iv_prime, (const __m128i*)plaintext,
plaintext_length, (__m128i*)ciphertext);
clhash(&(ctx->prf_context),
header, header_length, DOMAIN_1, ciphertext, plaintext_length, s);
cdms(s, s, ctx->expanded_key);
xor_bytes(tag, s, iv, TAGLEN);
}
int main() {
void * random = get_random_key_for_clhash(UINT64_C(0x23a23cf5033c3c81),UINT64_C(0xb3816f6a2c68e530));
uint64_t hashvalue1 = clhash(random,"my dog",6);
uint64_t hashvalue2 = clhash(random,"my cat",6);
uint64_t hashvalue3 = clhash(random,"my dog",6);
assert(hashvalue1 == hashvalue3);
assert(hashvalue1 != hashvalue2);// very likely to be true
free(random);
return 0;
}
void encrypt_final(riv_context_t* ctx,
const unsigned char* plaintext,
const unsigned long long plaintext_length,
const unsigned char* header,
const unsigned long long header_length,
unsigned char* ciphertext,
unsigned char tag[TAGLEN])
{
ALIGN(16)
uint8_t iv[BLOCKLEN];
clhash(&(ctx->prf_context),
header, header_length, DOMAIN_0, plaintext, plaintext_length, iv);
const __m128i iv_ = aes_encrypt(load(iv), ctx->expanced_enc_key);
encrypt(ctx, iv_, plaintext, plaintext_length, ciphertext);
storeu(tag, iv_);
}
int decrypt_final(riv_context_t* ctx,
const unsigned char* ciphertext,
const unsigned long long ciphertext_length,
const unsigned char* header,
const unsigned long long header_length,
const unsigned char tag[TAGLEN],
unsigned char* plaintext)
{
const __m128i iv = loadu(tag);
decrypt(ctx, iv, plaintext, ciphertext_length, ciphertext);
ALIGN(16)
uint8_t iv_prime[BLOCKLEN];
clhash(&(ctx->prf_context),
header, header_length, DOMAIN_0, plaintext, ciphertext_length, iv_prime);
const __m128i iv_prime_ = aes_encrypt(load(iv_prime), ctx->expanced_enc_key);
return _mm_testc_si128(iv, iv_prime_) - 1;
}
