Only SHA3/SHAKE Init Updates via FIPS202 API layer

[manastasova]

Issues:

Resolves (some of) #CryptoAlg-2810

Description of changes:

AWS-LC supports SHA3 and SHAKE algorithms though low level SHA3_Init, SHA3_Update, SHA3_Final and SHAKE_init, SHAKE_Final APIs. Currently, there are two issues with the implementation and usage of SHA3 and SHAKE:

• There is no support for SHAKE_Update function. SHAKE is implemented by calling SHAKE_Init, SHA3_Update and SHAKE_Final.
• SHAKE_Final allows multiple consecutive calls to enable incremental XOF output generation.

This PR introduces the APIs that need changes in the function parameter list. Particularly, SHA3_Init used a parameter |pad_char|, which was used for differentiating SHA3_Init from SHAKE_Init functions.

This PR introduces only the changes in the Init functions (FIPS202_Init, FIPS202_Reset, SHA3_Init, and SHAKE_Init):

• Introduce (partially) new API layers - FIPS202, SHA3 and SHAKE.
  • Keccak1600 layer (Keccak1600_Squeeze/Absorb Layer (rename) #2097) implements KeccakF1600 Absorb and Squeeze functions; Keccak1600 layer does not manage internal input/output buffers.
  • FIPS202 layer implements (so far) Reset and Init functions. (Update and Finalize functionalities are to be introduced in following PRs); FIPS202 layer manages the internal input/output buffers, allowing incremental requests (not necessarily multiple of block size) to Update (Absorb) and Squeeze for input/output processing. (Other functionalities, such as zero-ing of bitstate, block size checks, etc. are also handled by FIPS202 API layer).
    • FIPS202 layer implements (so far) Reset and Init common behavior between SHA3 and SHAKE algorithms.
    • FIPS202 layer checks/updates the |ctx->padded| flag when handling a common behavior between SHA3 and SHAKE algorithms.
  • SHA3 layer implements (so far) Init functionality (Update, and Final are to be introduced in following PRs);
  • SHAKE layer implements XOF SHAKE algorithm, therefore, offers (so far) Init functionality (Absorb, Squeeze, and Final functionalities are to be introduced in following PRs);

Call-outs:

All SHA3_Init calls are updated:

• digests.c
• sha3_test.cc

Testing:

./crypto/crypto_test --gtest_filter="KeccakInternalTest.*"
./crypto/crypto_test --gtest_filter="SHA3Test.*"
./crypto/crypto_test --gtest_filter="SHAKETest.*"

./crypto/crypto_test --gtest_filter="All/PerKEMTest.*"
./crypto/crypto_test --gtest_filter="All/PQDSAParameterTest.*"

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 91.17647% with 3 lines in your changes missing coverage. Please review.

Project coverage is 78.91%. Comparing base (94daeb2) to head (f7479d5).

Files with missing lines	Patch %	Lines
crypto/fipsmodule/sha/sha3.c	90.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2101      +/-   ##
==========================================
- Coverage   78.92%   78.91%   -0.02%     
==========================================
  Files         610      610              
  Lines      105137   105145       +8     
  Branches    14911    14903       -8     
==========================================
- Hits        82983    82977       -6     
- Misses      21503    21517      +14     
  Partials      651      651              

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