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Author image Felipe Gasper
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Crypt::Perl - Cryptography in pure Perl


Just as it sounds: cryptography with no non-core XS dependencies! This is useful if you don’t have access to other tools that do this work like OpenSSL, CryptX, etc. Of course, if you do have access to one of those tools, they may suit your purpose better.

See submodules for usage examples of:



Random number generation here comes from Bytes::Random::Secure::Tiny. See that module’s documentation for details of its reliability.

An extensive test suite is included that compares against OpenSSL and LibTomCrypt (i.e., CryptX), when available.

That said: NO GUARANTEES!!! It’s best to restrict use of this library to contexts where more “visible” cryptography libraries like the ones mentioned elsewhere here are unavailable.

And of course, OpenSSL has not been trouble-free, either …

Caveat emptor.



RSA key generation is slow—too slow, probably, unless you have Math::BigInt::GMP or Math::BigInt::Pari (either of which requires XS). It’s one application where pure-Perl cryptography just doesn’t seem feasible. :-( Everything else, though, including all ECDSA and Ed25519 operations, should be fine even in pure Perl.

Note that this distribution’s test suite is also pretty slow without an XS backend.


There are TODO items listed in the submodules; the following are general to the entire distribution.

  • Document the exception system so that applications can use it.

  • Add more tests, e.g., against CryptX.

  • Some formal security audit would be nice.

  • Make it faster :)


Much of the logic here comes from Kenji Urushima’s jsrsasign.

Most of the tests depend on the near-ubiquitous OpenSSL, without which the Internet would be a very, very different reality from what we know!

The Ed25519 logic is ported from forge.js.

Deterministic ECDSA logic derived in part from python-ecdsa.

Other parts are ported from LibTomCrypt.

Special thanks to Antonio de la Piedra for having submitted multiple high-quality, in-depth bug reports.


This library is licensed under the same license as Perl.


Felipe Gasper (FELIPE)