Computes multiplicative inverse of a positive integer big number with respect to specified modulus.
Syntax
IppStatus ippsModInv_BN(IppsBigNumState *e, IppsBigNumState *m, IppsBigNumState * d);
Parameters
e |
Integer big number of IppsBigNumState. |
m |
Modulus integer of IppsBigNumState. |
d |
Multiplicative inverse. |
Description
This function is declared in the ippcp.h file. The function uses the extended Euclidean algorithm to compute the multiplicative inverse of a given positive integer big number e with respect to the modulus specified by another positive integer big number m, where gcd (e, m) = 1.
The following pseudocode represents this function:
compute d such that d * e = 1 mod m.
Return Values
ippStsNoErr |
Indicates no error. Any other value indicates an error or warning. |
ippStsBadArgErr |
Indicates an error condition if e is less than or equal to 0. |
ippStsNullPtrErr |
Indicates an error condition if any of the specified pointers is NULL. |
ippStsBadModulusErr |
Indicates an error condition if the modulus e is more than m, or gcd (e,m) is more than 1, or m is less than or equal to 0. |
ippStsOutOfRangeErr |
Indicates an error condition if IppsBigNumState *d is smaller than the length of IppsBigNumState *m. |
Note
The size of IppsBigNumState *d should not be less than the length of IppsBigNumState *m.