GFpECSetPointOctString¶
Sets the coordinates of a point on an elliptic curve defined over GF(p).
Syntax¶
IppStatus ippsGFpECSetPointOctString(const Ipp8u* pStr, int strLen, IppsGFpECPoint* pPoint, IppsGFpECState* pEC);
Include Files¶
ippcp.h
Parameters¶
pStr |
Pointer octet string containing |
strLen |
Length of the input pStr string, in bytes. |
pPoint |
Pointer to the context of the elliptic curve point. |
pEC |
Pointer to the context of the elliptic cryptosystem. |
Description¶
This function sets the coordinates of a point onthe elliptic curve
defined over a prime finite field GF(p). The input data is the octet
string containing the pair (X, Y) ofcoordinates. The left half
of the pStr stringrepresents an X-coordinate and the right half
represents a Y-coordinate.The left byte in X and Y
representations corresponds to the mostsignificant byte of coordinates.
Length of each part is equal tothe length of the GF(p) field element
in bytes. Before using this function, you need to:
Define the elliptic curve domain parameters using the GFpECSet or GFpECSetStd and GFpECSetSubgroup functions
Create the context of the point on the elliptic curve using the GFpECPointGetSize and GFpECPointInit functions
Return Values¶
ippStsNoErr |
Indicates no error. Any other value indicates an error or warning. |
ippStsNullPtrErr |
Indicates an error when any of the specified pointers is NULL. |
ippStsContextMatchErr |
Indicates an error when one of the contexts pointed bypPoint orpEC is not valid or not a definedsubgroup. |
ippStsNotSupportedModeErr |
Indicates an error when the finite field over which the elliptic curve is initialized is not prime. |