RSA Security 5.2.2 manual There is no in generating a key pair, Break

Performing RSA Operations

keygenParams.modulusBits = 512; keygenParams.publicExponent.data = f4Data; keygenParams.publicExponent.len = 3;

if ((status = B_SetAlgorithmInfo (keypairGenerator, AI_RSAKeyGen, (POINTER)&keygenParams)) != 0)

break;

Step 3: Init

Look up the description and prototype for B_GenerateInit in Chapter 4 of the Reference Manual. For this example, you can use the following:

if ((status = B_GenerateInit (keypairGenerator, RSA_SAMPLE_CHOOSER, (A_SURRENDER_CTX *)NULL_PTR)) != 0)

break;

Here, you use NULL_PTR for the surrender context because B_GenerateInit is a speedy function. B_GenerateKeypair in Step 5 is the time-consuming function.

Step 4: Update

There is no Step 4 in generating a key pair.

Step 5: Generate

Find the description and prototype for B_GenerateKeypair in Chapter 4 of the Reference Manual. This function takes five arguments. The first is the algorithm object: for this example, it is keypairGenerator. The second and third are key objects. For this call, all you have to do is create the key objects; they will be set by B_GenerateKeypair. The fourth argument is a random algorithm. For this, complete Steps 1 through 4 of “Generating Random Numbers” on page 165. You do not need random bytes, only an algorithm that can generate them. The algorithm chooser you are using (defined in “Algorithm Choosers” on page 116) contains the AM for SHA1 random number generation.

The last argument is the surrender context. This function call can take a while, although the amount of time is not uniform. On slower machines, it may take over two or three minutes to generate a 512-bit key pair, or it may take only 17 seconds.

Crypto-C needs to find two primes of the proper size. To find a prime, Crypto-C

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