RSA_GenerateKeys

RSA_GenerateKeys#

Generates key components for the desired RSA cryptographic system.

Syntax#

IppStatus ippsRSA_GenerateKeys(const IppsBigNumState* pSrcPublicExp, IppsBigNumState* pModulus, IppsBigNumState* pPublicExp, IppsBigNumState* pPrivateExp, IppsRSAPrivateKeyState* pPrivateKeyType2, Ipp8u* pScratchBuffer, int nTrials, IppsPrimeState* pPrimeGen, IppBitSupplier rndFunc, void* pRndParam);

Include Files#

ippcp.h

Parameters#

pSrcPublicExp

Pointer to the IppsBigNumState context of the initial value for searching an RSA public exponent.

pModulus

Pointer to the generated RSA modulus.

pPublicExp

Pointer to the generated RSA public exponent.

pPrivateExp

Pointer to the generated RSA private exponent.

pPrivateKeyType2

Pointer to the generated RSA private key type 2.

pScratchBuffer

Pointer to the temporary buffer of size not less than returned by the RSA_GetBufferSizePrivateKey function.

nTrials

Security parameter specified for the Miller-Rabin test for probable primality.

pPrimeGen

Ignored (pass NULL). Prime number generation uses rndFunc directly.

rndFunc

Pseudorandom number generator.

pRndParam

Pointer to the context of the pseudorandom number generator.

Description#

This function generates public and private keys of the desired RSA cryptographic system.

This function sequentially performs the following computations:

  1. Generates random probable prime numbers p and q using the specified pseudorandom number generator rndFunc.

  2. Computes the RSA composite modulus n = (p*q).

  3. Based on the generated p and q factors, computes all the other CRT-related RSA components: dP = d mod (p-1), dQ = d mod (q-1) and qInv = 1/q mod p.

To generate RSA keys using the RSA_GenerateKeys function, call it in the following sequence of steps:

  1. Establish the pseudorandom number generator.

  2. Define the RSA private key type 2 in successive calls to the RSA_GetSizePrivateKeyType2 and RSA_InitPrivateKeyType2 functions with desired values of factorPBitSize and factorQBitSize parameters.

  3. Allocate a temporary buffer of a suitable size.

  4. Set up the initial value of the public exponent pSrcPublicExp.

  5. Call RSA_GenerateKeys.

    • If RSA_GenerateKeys returns IppNoErr, the key pair is generated.

    • If RSA_GenerateKeys returns ippStsInsufficientEntropy, repeat this step.

Return Values#

ippStsNoErr

Indicates no error. Any other value indicates an error or warning.

ippStsNullPtrErr

Indicates an error condition if any of the specified pointers is NULL.

ippStsContextMatchErr

Indicates an error condition if the context parameter does not match the operation.

ippStsSizeErr

Indicates an error condition if the bit length of any key component specified by pModulus, pPublicExp or pPrivateExp is not sufficient to hold the value.

ippStsOutOfRangeErr

Indicates an error condition if the initial value for searching the public exponent, specified by pSrcPublicExp, is not positive.

ippStsBadArgErr

Indicates an error condition if the public exponent specified by pSrcPublicExp is an even value or is less than 3.

ippStsErr

Indicates an internal error condition.

ippStsInsufficientEntropy

Indicates a warning condition if the prime number generation fails due to a poor choice of entropy.

Related Information

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