package nocrypto

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nocrypto - Simpler crypto


nocrypto is a small cryptographic library that puts emphasis on the applicative style and ease of use. It includes basic ciphers (AES, 3DES, RC4), hashes (MD5, SHA1, SHA2), public-key primitives (RSA, DSA, DH) and a strong RNG (Fortuna).

RSA timing attacks are countered by blinding. AES timing attacks are avoided by delegating to AES-NI.


Interface is documented. Also online.


  --with-unix BOOL
  --with-lwt BOOL
  --xen BOOL
  --freestanding BOOL

./pkg/ test


RNG seeding

If RNG fails with Fatal error: exception Uncommon.Boot.Unseeded_generator, you need to seed it.


let () = Nocrypto_entropy_unix.initialize ()


let () = Nocrypto_entropy_lwt.initialize () |> ignore
Illegal instructions
Program terminated with signal SIGILL, Illegal instruction.
#0  _mm_aeskeygenassist_si128 (__C=<optimized out>, __X=...)

Nocrypto has CPU acceleration support (SSE2+AES-NI), but no run-time autodetection yet. You compiled the library with acceleration, but you are using it on a machine that does not support it.

pkg/ build --accelerate false force-disables non-portable code.

pkg/ build --accelerate true force-enables non-portable code.

The flag can also be set via the NOCRYPTO_ACCELERATE environment variable. When unset, it maches the capabilities of the build machine.