Skip to content

Latest commit

 

History

History
153 lines (142 loc) · 4.04 KB

cppapi.md

File metadata and controls

153 lines (142 loc) · 4.04 KB
Raw

C++ API Documentation

class BigNumber

class BigNumber

This class is a wrap of OpenSSL BIGNUM structure with additional methods

Fields:
BIGNUM* bn;

OpenSSL BIGNUM variable to be wrapped

Constructors:
BigNumber(unsigned char * x, int n);

Creates object from unsigned char buffer of n size

BigNumber(int x);

Creates object from int number

BigNumber(const BigNumber& bn);

Copy constructor

BigNumber(BIGNUM* x);

Creates object from OpenSSL BIGNUM

Methods:
int decimal();

Returns decimal value of bn field

char* toDecString();

Returns pointer to a char representation of bn field

class Curve

class Curve

This class is a wrap of OpenSSL EC_POINT structure with additional fields and methods

Constructor:
Curve(BigNumber a, BigNumber b, BigNumber p, BigNumber order, BigNumber gx, BigNumber gy)
  • [in] a - a parameter of elliptic curve
  • [in] b - p parameter of elliptic curve
  • [in] p - field of elliptic cupve
  • [in] order - Number of points of elliptic curve
  • [in] gx - x-coordinate of group generator
  • [in] gy - y-coordinate of group generator

mul

EC_POINT* mul(BigNumber n, EC_POINT *P, Curve *crv);

Multiply point by number

  • [in] n - number
  • [in] P - point
  • [in] crv - Elliptic curve
  • return - Result of multiplication

createMPK

EC_POINT* createMPK(BigNumber msk, EC_POINT *P, Curve *crv);

Creates Master Public Key. Wrapper of mul() function.

  • [in] msk - number
  • [in] P - point
  • [in] crv - Elliptic curve
  • return - Master Public Key

getRandom

BigNumber getRandom(BigNumber max);

Generates non-zero random number in range from 1 to max

  • [in] max - Range upper bound
  • return - Random number

shamir

vector<BigNumber> shamir(BigNumber secretM, int participantN, int sufficientK, BigNumber q);

Shamir's secret key sharing scheme.

  • [in] secretM - SecretKey to be shared
  • [in] participantN - total number of parts
  • [in] sufficientK - min number of participants
  • [in] q - Finite field order
  • return - vector of SecretKey shadows

keyProj

vector<EC_POINT*> keyProj(vector<int> coalition, vector<BigNumber> shares, EC_POINT *Q, Curve *crv);

Creates vector of Public Keys. Multiply elements of shares by Q

  • [in] coalition - vector of participant's ID's involved in Shamir's secret key sharing scheme
  • [in] shares - vector of secret key shares
  • [in] Q - point of elliptic curve
  • [in] crv - Elliptic curve
  • return - vector of Public keys

keyRecovery

EC_POINT* keyRecovery(std::vector<EC_POINT*> proj, vector<int> coalition, BigNumber q, Curve *crv);

SecretKey recovery. Gets session SecretKey SK from participants key shadows

  • [in] proj - vector of participant's Public keys
  • [in] coalition - vector of participant's ID's involved in secret key sharing scheme
  • [in] q - Finite field order
  • return - SecretKey SK - point of EC. SK = msk * Q; (Q - Public key of LPoS)

weilPairing

BigNumber weilPairing(EC_POINT *P, EC_POINT *Q, EC_POINT *S, Curve *crv);
  • [in] P -
  • [in] Q -
  • [in] S -
  • [in] crv - Elliptic curve

Operators

BigNumber operator * (const BigNumber &a, const BigNumber &b);
BigNumber operator % (const BigNumber &a, const BigNumber &b);
BigNumber operator - (const BigNumber &a, const BigNumber &b);
BigNumber operator + (const BigNumber &a, const BigNumber &b);

Operators overloading for BigNumber class