Add support for PKCS12_set_mac

[samuel40791765]

Issues:

Addresses CryptoAlg-2821

Description of changes:

Ruby has added a binding for an additional function called PKCS12_set_mac in it's master branch: ruby/ruby@c79b435 This was discovered prior to the PR for Ruby's CI integration with the master branch being merged: #2071

OpenSSL's implementation of the function directly sets a designated mac field within the PKCS12 structure. Our PKCS12 structure is folded into a string of bytes along with its length and there aren't any available fields for us to directly set. This means that AWS-LC's implementation of PKCS12_set_mac has to parse the proper contents from PKCS12 and rerun the key and mac generation with the new parameters provided.

Call-outs:

1. The parsing logic is similar to PKCS12_get_key_and_certs, but the logic can't be shared. This is because we need to maintain pointers to certain parts of the CBS parsers in PKCS12_set_mac, so that we can properly rewrite the contents later.
2. I've abstracted the key and mac generation in PKCS12_create and PKCS12_set_mac to a single function called pkcs12_gen_and_write_mac.
3. OpenSSL 3.0 uses SHA-256 as the default hash, yet OpenSSL 1.1.1 uses SHA1. TODO: Make a decision

Testing:

New Tests

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 85.71429% with 16 lines in your changes missing coverage. Please review.

Project coverage is 78.96%. Comparing base (81f138a) to head (72a0f41).

Files with missing lines	Patch %	Lines
crypto/pkcs8/pkcs8_x509.c	78.94%	16 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2128      +/-   ##
==========================================
+ Coverage   78.95%   78.96%   +0.01%     
==========================================
  Files         610      610              
  Lines      105293   105372      +79     
  Branches    14919    14921       +2     
==========================================
+ Hits        83136    83211      +75     
- Misses      21505    21510       +5     
+ Partials      652      651       -1     

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[skmcgrail]

Minor style feedback on tests, non-blocking.

[skmcgrail]

Suggested change

	static bool PKCS12CreateVector(bssl::UniquePtr<PKCS12> *p12, EVP_PKEY *pkey,
	static bool PKCS12CreateVector(bssl::UniquePtr<PKCS12> & p12, EVP_PKEY *pkey,

You can just pass this by C++ reference right? Then you don't have to take the address of the UniquePtr every time you pass it in.

[samuel40791765]

Agree with both comments, this was mostly me trying to hack something together while allowing the original code to use the same function.