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ModInv_BN

Computes multiplicative inverse of a positive integer big number with respect to specified modulus.

Syntax

IppStatus ippsModInv_BN(IppsBigNumState*
pA
, IppsBigNumState*
pM
, IppsBigNumState*
pInv
);
Include Files
ippcp.h
Parameters
pA
Pointer to the integer big number of
IppsBigNumState
.
pM
Pointer to the modulus integer of
IppsBigNumState
.
pInv
Pointer to the multiplicative inverse.
Description
The function uses the extended Euclidean algorithm to compute the multiplicative inverse of a given positive integer big number
pA
with respect to the modulus specified by another positive integer big number
pM
, where
gcd
(
pA
,
pM
) = 1
.
The following pseudocode represents this function:
compute
pInv
such that
pInv
*
pA
= 1
mod
pM
.
Return Values
ippStsNoErr
Indicates no error. Any other value indicates an error or warning.
ippStsBadArgErr
Indicates an error condition if
pA
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
pA
is greater than
pM
, or
gcd (pA,pM)
is greater than 1, or
pM
is less than or equal to 0.
ippStsOutOfRangeErr
Indicates an error condition if
IppsBigNumState *
pInv
is smaller than the length of
IppsBigNumState *
pM
.
ippStsContextMatchErr
Indicates an error condition if any of the context parameters does not match the operation.
ippStsScaleRangeErr
Indicates an error condition if
pA
is greater than or equal to
pM
The size of
IppsBigNumState *
pInv
should not be less than the length of
IppsBigNumState *
pM
.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.