Strongswan compiled without kdf module fails with "KDF_PRF with PRF_HMAC_SHA1 not supported" for openssl 3.5.1

[japc]

Output of brew config

HOMEBREW_VERSION: 4.5.9
ORIGIN: https://github.com/Homebrew/brew
HEAD: 700d67a85e0129ab8a893ff69246943479e33df1
Last commit: 3 days ago
Branch: stable
Core tap JSON: 10 Jul 11:49 UTC
Core cask tap JSON: 10 Jul 11:49 UTC
HOMEBREW_PREFIX: /opt/homebrew
HOMEBREW_CASK_OPTS: []
HOMEBREW_MAKE_JOBS: 8
Homebrew Ruby: 3.4.4 => /opt/homebrew/Library/Homebrew/vendor/portable-ruby/3.4.4/bin/ruby
CPU: octa-core 64-bit arm_blizzard_avalanche
Clang: 17.0.0 build 1700
Git: 2.39.5 => /Library/Developer/CommandLineTools/usr/bin/git
Curl: 8.7.1 => /usr/bin/curl
macOS: 15.5-arm64
CLT: 16.4.0.0.1.1747106510
Xcode: N/A
Rosetta 2: false

Output of brew doctor

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Description of issue

Current compilation of Strongswan, without the 'kdf' plugin fails when the key derivation is sha1. It seems to be unsupported on openssl 3.5.1. With 'kdf' enabled PRF_HMAC_SHA1 works.

The kdf plugin shows as enabled by default on the stronswan docs but gets disabled on compilation with the --disable-defaults.

Is there any reason for this?

[carlocab]

--disable-defaults originates from when the formula was first introduced, likely to give the formula better control over what is and isn't enabled.

If the kdf plugin doesn't add any additional dependencies then we'll almost certainly accept a PR that enables it in the formula.

[japc]

Thank you.

There's no dependencies (did test on multiple MacOS). Did a PR. Don't know if I got it right though.