39 lines
1.3 KiB
Markdown
39 lines
1.3 KiB
Markdown
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# Contractless PHP Crypto Interoperability
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This harness verifies that the native libraries packaged by
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`contractless-php-crypto` produce data compatible with Contractless.
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## Results
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- The C implementation wrapped by `jedisct1/PHP-Skein-Hash` produces the
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same 32-byte Skein-256 output as the Rust `skein` crate used by
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Contractless.
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- Unmodified `Falcon-padded-512` message handling is not compatible with
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Contractless `fn-dsa 0.3.0`.
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- `Falcon-padded-512` keys and fixed signatures use the same Contractless
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sizes: 897-byte public keys, 1,281-byte private keys, and 666-byte
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signatures.
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- Both signing implementations are compatible when liboqs receives the
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message framing used by Contractless:
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```text
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SHAKE256(public_key, 64 bytes) || 0x00 || 0x00 || original_message
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```
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The two zero bytes represent raw-message mode and an empty domain context.
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With that adapter:
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- Contractless Rust signatures verify through liboqs.
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- Liboqs signatures verify through Contractless Rust.
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## Required liboqs algorithm
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Use `Falcon-padded-512`. Do not use variable-length `Falcon-512`.
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## Regression requirement
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Run these tests whenever Contractless changes its `fn-dsa`, `skein`, or
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signature-framing dependencies. Matching key and signature lengths alone
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does not establish compatibility.
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