v/vlib/crypto/md5/md5.v

147 lines
3.3 KiB
V
Raw Normal View History

2019-07-16 14:20:51 +02:00
// Copyright (c) 2019 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 md5 implements the MD5 hash algorithm as defined in RFC 1321.
// MD5 is cryptographically broken and should not be used for secure
// applications.
// Based off: https://github.com/golang/go/blob/master/src/crypto/md5
// Last commit: https://github.com/golang/go/commit/ed7f323c8f4f6bc61a75146bf34f5b8f73063a17
2019-07-16 14:20:51 +02:00
module md5
import encoding.binary
const (
// The size of an MD5 checksum in bytes.
2019-10-24 13:48:20 +02:00
size = 16
2019-07-16 14:20:51 +02:00
// The blocksize of MD5 in bytes.
2019-10-24 13:48:20 +02:00
block_size = 64
2019-07-16 14:20:51 +02:00
)
const (
2019-10-24 13:48:20 +02:00
init0 = 0x67452301
init1 = 0xEFCDAB89
init2 = 0x98BADCFE
init3 = 0x10325476
2019-07-16 14:20:51 +02:00
)
// Digest represents the partial evaluation of a checksum.
struct Digest {
mut:
s []u32
x []byte
nx int
len u64
}
fn (d mut Digest) reset() {
d.s = [u32(0)].repeat(4)
2019-10-24 13:48:20 +02:00
d.x = [byte(0)].repeat(block_size)
d.s[0] = u32(init0)
d.s[1] = u32(init1)
d.s[2] = u32(init2)
d.s[3] = u32(init3)
2019-07-16 14:20:51 +02:00
d.nx = 0
d.len = 0
2019-07-16 14:20:51 +02:00
}
// new returns a new Digest (implementing hash.Hash) computing the MD5 checksum.
2019-09-02 19:22:19 +02:00
pub fn new() &Digest {
2019-07-16 14:20:51 +02:00
mut d := &Digest{}
d.reset()
return d
}
2019-08-07 13:37:07 +02:00
pub fn (d mut Digest) write(p_ []byte) ?int {
mut p := p_
2019-07-16 14:20:51 +02:00
nn := p.len
d.len += u64(nn)
if d.nx > 0 {
n := copy(d.x[d.nx..], p)
2019-07-16 14:20:51 +02:00
d.nx += n
2019-10-24 13:48:20 +02:00
if d.nx == block_size {
2019-08-07 13:37:07 +02:00
block(mut d, d.x)
2019-07-16 14:20:51 +02:00
d.nx = 0
}
if n >= p.len {
p = []byte
} else {
p = p[n..]
2019-07-16 14:20:51 +02:00
}
}
2019-10-24 13:48:20 +02:00
if p.len >= block_size {
n := p.len &~ (block_size - 1)
block(mut d, p[..n])
2019-07-16 14:20:51 +02:00
if n >= p.len {
p = []byte
} else {
p = p[n..]
2019-07-16 14:20:51 +02:00
}
}
if p.len > 0 {
2019-07-29 16:33:35 +02:00
d.nx = copy(d.x, p)
2019-07-16 14:20:51 +02:00
}
return nn
}
2019-09-29 15:44:52 +02:00
pub fn (d &Digest) sum(b_in []byte) []byte {
2019-07-16 14:20:51 +02:00
// Make a copy of d so that caller can keep writing and summing.
mut d0 := *d
hash := d0.checksum()
2019-09-29 15:44:52 +02:00
mut b_out := b_in.clone()
2019-07-16 14:20:51 +02:00
for b in hash {
2019-09-29 15:44:52 +02:00
b_out << b
2019-07-16 14:20:51 +02:00
}
2019-09-29 15:44:52 +02:00
return b_out
2019-07-16 14:20:51 +02:00
}
pub fn (d mut Digest) checksum() []byte {
// Append 0x80 to the end of the message and then append zeros
// until the length is a multiple of 56 bytes. Finally append
// 8 bytes representing the message length in bits.
//
// 1 byte end marker :: 0-63 padding bytes :: 8 byte length
// tmp := [1 + 63 + 8]byte{0x80}
mut tmp := [byte(0)].repeat(1 + 63 + 8)
2019-07-16 14:20:51 +02:00
tmp[0] = 0x80
2019-09-28 13:02:57 +02:00
pad := int((55 - int(d.len)) % u64(64)) // calculate number of padding bytes
binary.little_endian_put_u64(mut tmp[1+pad..], d.len<<u64(3)) // append length in bits
d.write(tmp[..1+pad+8])
2019-07-16 14:20:51 +02:00
// The previous write ensures that a whole number of
// blocks (i.e. a multiple of 64 bytes) have been hashed.
if d.nx != 0 {
panic('d.nx != 0')
}
2019-10-24 13:48:20 +02:00
digest := [byte(0)].repeat(size)
2019-07-16 14:20:51 +02:00
binary.little_endian_put_u32(mut digest, d.s[0])
binary.little_endian_put_u32(mut digest[4..], d.s[1])
binary.little_endian_put_u32(mut digest[8..], d.s[2])
binary.little_endian_put_u32(mut digest[12..], d.s[3])
2019-07-16 14:20:51 +02:00
return digest
}
2019-07-17 11:00:15 +02:00
// sum returns the MD5 checksum of the data.
2019-07-16 14:20:51 +02:00
pub fn sum(data []byte) []byte {
mut d := new()
2019-08-07 13:37:07 +02:00
d.write(data)
2019-07-16 14:20:51 +02:00
return d.checksum()
}
2019-08-07 09:53:33 +02:00
fn block(dig mut Digest, p []byte) {
2019-07-17 11:00:15 +02:00
// For now just use block_generic until we have specific
// architecture optimized versions
2019-08-07 09:53:33 +02:00
block_generic(mut dig, p)
2019-07-17 11:00:15 +02:00
}
2019-10-24 13:48:20 +02:00
pub fn (d &Digest) size() int { return size }
2019-07-16 14:20:51 +02:00
2019-10-24 13:48:20 +02:00
pub fn (d &Digest) block_size() int { return block_size }
2019-09-02 19:22:19 +02:00
pub fn hexhash(s string) string { return sum(s.bytes()).hex() }