152 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			V
		
	
	
			
		
		
	
	
			152 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			V
		
	
	
// Copyright (c) 2019-2020 Alexander Medvednikov. All rights reserved.
 | 
						|
// Use of this source code is governed by an MIT license
 | 
						|
// that can be found in the LICENSE file.
 | 
						|
 | 
						|
// Package sha1 implements the SHA-1 hash algorithm as defined in RFC 3174.
 | 
						|
 | 
						|
// SHA-1 is cryptographically broken and should not be used for secure
 | 
						|
// applications.
 | 
						|
 | 
						|
// Based off:   https://github.com/golang/go/blob/master/src/crypto/sha1
 | 
						|
// Last commit: https://github.com/golang/go/commit/3ce865d7a0b88714cc433454ae2370a105210c01
 | 
						|
 | 
						|
module sha1
 | 
						|
 | 
						|
import encoding.binary
 | 
						|
 | 
						|
pub const(
 | 
						|
	// The size of a SHA-1 checksum in bytes.
 | 
						|
	size     = 20
 | 
						|
	// The blocksize of SHA-1 in bytes.
 | 
						|
	block_size = 64
 | 
						|
)
 | 
						|
 | 
						|
const (
 | 
						|
	chunk = 64
 | 
						|
	init0 = 0x67452301
 | 
						|
	init1 = 0xEFCDAB89
 | 
						|
	init2 = 0x98BADCFE
 | 
						|
	init3 = 0x10325476
 | 
						|
	init4 = 0xC3D2E1F0
 | 
						|
)
 | 
						|
 | 
						|
// digest represents the partial evaluation of a checksum.
 | 
						|
struct Digest {
 | 
						|
mut:
 | 
						|
	h   []u32
 | 
						|
	x   []byte
 | 
						|
	nx  int
 | 
						|
	len u64
 | 
						|
}
 | 
						|
 | 
						|
fn (mut d Digest) reset() {
 | 
						|
	d.x = []byte{len:(chunk)}
 | 
						|
	d.h = []u32{len:(5)}
 | 
						|
	d.h[0] = u32(init0)
 | 
						|
	d.h[1] = u32(init1)
 | 
						|
	d.h[2] = u32(init2)
 | 
						|
	d.h[3] = u32(init3)
 | 
						|
	d.h[4] = u32(init4)
 | 
						|
	d.nx = 0
 | 
						|
	d.len = 0
 | 
						|
}
 | 
						|
 | 
						|
// new returns a new Digest (implementing hash.Hash) computing the SHA1 checksum.
 | 
						|
pub fn new() &Digest {
 | 
						|
	mut d := &Digest{}
 | 
						|
	d.reset()
 | 
						|
	return d
 | 
						|
}
 | 
						|
 | 
						|
pub fn (mut d Digest) write(p_ []byte) int {
 | 
						|
	mut p := p_
 | 
						|
	nn := p.len
 | 
						|
	d.len += u64(nn)
 | 
						|
 | 
						|
	if d.nx > 0 {
 | 
						|
		n := copy(d.x[d.nx..], p)
 | 
						|
		d.nx += n
 | 
						|
		if d.nx == chunk {
 | 
						|
			block(mut d, d.x)
 | 
						|
			d.nx = 0
 | 
						|
		}
 | 
						|
		if n >= p.len {
 | 
						|
			p = []
 | 
						|
		} else {
 | 
						|
			p = p[n..]
 | 
						|
		}
 | 
						|
	}
 | 
						|
	if p.len >= chunk {
 | 
						|
		n := p.len &~ (chunk - 1)
 | 
						|
		block(mut d, p[..n])
 | 
						|
		if n >= p.len {
 | 
						|
			p = []
 | 
						|
		} else {
 | 
						|
			p = p[n..]
 | 
						|
		}
 | 
						|
	}
 | 
						|
	if p.len > 0 {
 | 
						|
		d.nx = copy(d.x, p)
 | 
						|
	}
 | 
						|
	return nn
 | 
						|
}
 | 
						|
 | 
						|
pub fn (d &Digest) sum(b_in []byte) []byte {
 | 
						|
	// Make a copy of d so that caller can keep writing and summing.
 | 
						|
	mut d0 := *d
 | 
						|
	hash := d0.checksum()
 | 
						|
	mut b_out := b_in.clone()
 | 
						|
	for b in hash {
 | 
						|
		b_out << b
 | 
						|
	}
 | 
						|
	return b_out
 | 
						|
}
 | 
						|
 | 
						|
fn (mut d Digest) checksum() []byte {
 | 
						|
	mut len := d.len
 | 
						|
	// Padding.  Add a 1 bit and 0 bits until 56 bytes mod 64.
 | 
						|
	mut tmp := []byte{len:(64)}
 | 
						|
 | 
						|
	tmp[0] = 0x80
 | 
						|
 | 
						|
	if int(len)%64 < 56 {
 | 
						|
		d.write(tmp[..56-int(len)%64])
 | 
						|
	} else {
 | 
						|
		d.write(tmp[..64+56-int(len)%64])
 | 
						|
	}
 | 
						|
 | 
						|
	// Length in bits.
 | 
						|
	len <<= 3
 | 
						|
	binary.big_endian_put_u64(mut tmp, len)
 | 
						|
	d.write(tmp[..8])
 | 
						|
 | 
						|
	mut digest := []byte{len:(size)}
 | 
						|
 | 
						|
	binary.big_endian_put_u32(mut digest, d.h[0])
 | 
						|
	binary.big_endian_put_u32(mut digest[4..], d.h[1])
 | 
						|
	binary.big_endian_put_u32(mut digest[8..], d.h[2])
 | 
						|
	binary.big_endian_put_u32(mut digest[12..], d.h[3])
 | 
						|
	binary.big_endian_put_u32(mut digest[16..], d.h[4])
 | 
						|
 | 
						|
	return digest
 | 
						|
}
 | 
						|
 | 
						|
// Sum returns the SHA-1 checksum of the data.
 | 
						|
pub fn sum(data []byte) []byte {
 | 
						|
	mut d := new()
 | 
						|
	d.write(data)
 | 
						|
	return d.checksum()
 | 
						|
}
 | 
						|
 | 
						|
fn block(mut dig Digest, p []byte) {
 | 
						|
	// For now just use block_generic until we have specific
 | 
						|
	// architecture optimized versions
 | 
						|
	block_generic(mut dig, p)
 | 
						|
}
 | 
						|
 | 
						|
pub fn (d &Digest) size() int { return size }
 | 
						|
 | 
						|
pub fn (d &Digest) block_size() int { return block_size }
 | 
						|
 | 
						|
pub fn hexhash(s string) string { return sum(s.bytes()).hex() }
 |