#ifndef _SECOTRMATH_H_
#define _SECOTRMATH_H_
#include <CoreFoundation/CFBase.h>
#include <corecrypto/ccn.h>
#include <corecrypto/ccaes.h>
#include <corecrypto/ccmode.h>
#define kOTRAuthKeyBytes 16
#define kOTRAuthMACKeyBytes 32
#define kOTRMessageKeyBytes 16
#define kOTRMessageMacKeyBytes 20
#define kExponentiationBits 1536
#define kExponentiationUnits ccn_nof(kExponentiationBits)
#define kExponentiationBytes ((kExponentiationBits+7)/8)
#define kSHA256HMAC160Bits 160
#define kSHA256HMAC160Bytes (kSHA256HMAC160Bits/8)
void OTRExponentiate(cc_unit* res, const cc_unit* base, const cc_unit* exponent);
void OTRGroupExponentiate(cc_unit* result, const cc_unit* exponent);
OSStatus GetRandomBytesInLSBs(size_t bytesOfRandomness, size_t n, cc_unit* place);
OSStatus FillWithRandomBytes(size_t n, cc_unit* place);
typedef enum {
kSSID = 0x00,
kCs = 0x01,
kM1 = 0x02,
kM2 = 0x03,
kM1Prime = 0x04,
kM2Prime = 0x05
} KeyType;
void DeriveOTR256BitsFromS(KeyType whichKey, size_t sSize, const cc_unit* s, size_t keySize, uint8_t* key);
void DeriveOTR128BitPairFromS(KeyType whichHalf, size_t sSize, const cc_unit* s,
size_t firstKeySize, uint8_t* firstKey,
size_t secondKeySize, uint8_t* secondKey);
void DeriveOTR64BitsFromS(KeyType whichKey, size_t sSize, const cc_unit* s,
size_t firstKeySize, uint8_t* firstKey);
void AES_CTR_HighHalf_Transform(size_t keySize, const uint8_t* key,
uint64_t highHalf,
size_t howMuch, const uint8_t* from,
uint8_t* to);
void AES_CTR_IV0_Transform(size_t keySize, const uint8_t* key,
size_t howMuch, const uint8_t* from,
uint8_t* to);
#endif