sha256

Documentation

Overview

The API for SHA256-2 according to https://en.wikipedia.org/wiki/SHA-2.

Index

• Variables
• func Hash(api builder.API, in []vars.Byte) [32]vars.Byte
• func HashAndTruncate(api builder.API, in []vars.Byte, nbBits int) vars.Variable

Variables

var H = []uint32{
	0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A, 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19,
}

First 32 bits of the fractional parts of the square roots of the first 8 primes. Reference: https://en.wikipedia.org/wiki/SHA-2

var K = []uint32{
	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
}

First 32 bits of the fractional parts of the cube roots of the first 64 primes. Reference: https://en.wikipedia.org/wiki/SHA-2

Functions

func Hash

func Hash(api builder.API, in []vars.Byte) [32]vars.Byte

Computes the SHA256-2 hash of the input bytes. Note that at compile time of the circuit, len(in) must be a constant.

func HashAndTruncate

func HashAndTruncate(api builder.API, in []vars.Byte, nbBits int) vars.Variable

Computes sha256(in) && ((1 << nbBits) - 1).