Motivation:

At times we might need to get the raw elements of an RSA key, e.g when debugging.

Modifications:

Add a getKeyPrimitives method to the RSA (public and private) key structures that returns the elements.
To do this we leverage the built in BoringSSL methods (CCryptoBoringSSL_RSA_get0_n etc.) which return the raw elements of the key. In the Security version of the key we convert the key to a BoringSSL one and just call the BoringSSL method.

Once we get ASN.1 support in _CryptoExtras it might make sense switching the implementation of this method to decode the ASN.1 structure and returns the elements from there.

Result:

New APIs to fetch the key primitives.

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Co-authored-by: Cory Benfield <[email protected]>

This adds a _createFromNumbers API which creates an RSA key generating p and q primes based on n, e and d

Motivation:

There might be cases where private RSA keys have to be generated based on their raw elements (modulus n, exponent e and private exponent d) without p and q. These are random primes which are integral parts of the key but can be generated based on the former numbers, and are not always included when representing RSA keys, for example these parameters are not required in JWKs

Modifications:

This adds a static _createFromNumbers method which creates a new RSA key given its raw modulus, exponent and private exponent, generating the needed p and q primes without having to provide them as parameters. The algorithm to generate primes is based on a hybrid approach of the Miller Rabin primality test and the proof of Fact 1 in Dan Boneh's Twenty Years of Attacks on the RSA Cryptosystem paper. To write this algorithm, some additions had to be made to the ArbitraryPrecisionInteger

Result:

Private RSA keys can now be generated without providing p and q

Motivation:

The privacy manifest is only required on Darwin. It's currently included
on all platforms which results in build warnings.

Modifications:

- Only include manifest on Darwin
- Exclude the privacy manifest from the build on other platforms

Result:

- Fewer warnings
- Resolves #256

…ptoKitASN1Error (#266)