status-go/vendor/github.com/minio/blake2b-simd/blake2b.go

302 lines
7.5 KiB
Go

// Written in 2012 by Dmitry Chestnykh.
//
// To the extent possible under law, the author have dedicated all copyright
// and related and neighboring rights to this software to the public domain
// worldwide. This software is distributed without any warranty.
// http://creativecommons.org/publicdomain/zero/1.0/
// Package blake2b implements BLAKE2b cryptographic hash function.
package blake2b
import (
"encoding/binary"
"errors"
"hash"
)
const (
BlockSize = 128 // block size of algorithm
Size = 64 // maximum digest size
SaltSize = 16 // maximum salt size
PersonSize = 16 // maximum personalization string size
KeySize = 64 // maximum size of key
)
type digest struct {
h [8]uint64 // current chain value
t [2]uint64 // message bytes counter
f [2]uint64 // finalization flags
x [BlockSize]byte // buffer for data not yet compressed
nx int // number of bytes in buffer
ih [8]uint64 // initial chain value (after config)
paddedKey [BlockSize]byte // copy of key, padded with zeros
isKeyed bool // indicates whether hash was keyed
size uint8 // digest size in bytes
isLastNode bool // indicates processing of the last node in tree hashing
}
// Initialization values.
var iv = [8]uint64{
0x6a09e667f3bcc908, 0xbb67ae8584caa73b,
0x3c6ef372fe94f82b, 0xa54ff53a5f1d36f1,
0x510e527fade682d1, 0x9b05688c2b3e6c1f,
0x1f83d9abfb41bd6b, 0x5be0cd19137e2179,
}
// Config is used to configure hash function parameters and keying.
// All parameters are optional.
type Config struct {
Size uint8 // digest size (if zero, default size of 64 bytes is used)
Key []byte // key for prefix-MAC
Salt []byte // salt (if < 16 bytes, padded with zeros)
Person []byte // personalization (if < 16 bytes, padded with zeros)
Tree *Tree // parameters for tree hashing
}
// Tree represents parameters for tree hashing.
type Tree struct {
Fanout uint8 // fanout
MaxDepth uint8 // maximal depth
LeafSize uint32 // leaf maximal byte length (0 for unlimited)
NodeOffset uint64 // node offset (0 for first, leftmost or leaf)
NodeDepth uint8 // node depth (0 for leaves)
InnerHashSize uint8 // inner hash byte length
IsLastNode bool // indicates processing of the last node of layer
}
var (
defaultConfig = &Config{Size: Size}
config256 = &Config{Size: 32}
)
func verifyConfig(c *Config) error {
if c.Size > Size {
return errors.New("digest size is too large")
}
if len(c.Key) > KeySize {
return errors.New("key is too large")
}
if len(c.Salt) > SaltSize {
// Smaller salt is okay: it will be padded with zeros.
return errors.New("salt is too large")
}
if len(c.Person) > PersonSize {
// Smaller personalization is okay: it will be padded with zeros.
return errors.New("personalization is too large")
}
if c.Tree != nil {
if c.Tree.Fanout == 1 {
return errors.New("fanout of 1 is not allowed in tree mode")
}
if c.Tree.MaxDepth < 2 {
return errors.New("incorrect tree depth")
}
if c.Tree.InnerHashSize < 1 || c.Tree.InnerHashSize > Size {
return errors.New("incorrect tree inner hash size")
}
}
return nil
}
// New returns a new hash.Hash configured with the given Config.
// Config can be nil, in which case the default one is used, calculating 64-byte digest.
// Returns non-nil error if Config contains invalid parameters.
func New(c *Config) (hash.Hash, error) {
if c == nil {
c = defaultConfig
} else {
if c.Size == 0 {
// Set default size if it's zero.
c.Size = Size
}
if err := verifyConfig(c); err != nil {
return nil, err
}
}
d := new(digest)
d.initialize(c)
return d, nil
}
// initialize initializes digest with the given
// config, which must be non-nil and verified.
func (d *digest) initialize(c *Config) {
// Create parameter block.
var p [BlockSize]byte
p[0] = c.Size
p[1] = uint8(len(c.Key))
if c.Salt != nil {
copy(p[32:], c.Salt)
}
if c.Person != nil {
copy(p[48:], c.Person)
}
if c.Tree != nil {
p[2] = c.Tree.Fanout
p[3] = c.Tree.MaxDepth
binary.LittleEndian.PutUint32(p[4:], c.Tree.LeafSize)
binary.LittleEndian.PutUint64(p[8:], c.Tree.NodeOffset)
p[16] = c.Tree.NodeDepth
p[17] = c.Tree.InnerHashSize
} else {
p[2] = 1
p[3] = 1
}
// Initialize.
d.size = c.Size
for i := 0; i < 8; i++ {
d.h[i] = iv[i] ^ binary.LittleEndian.Uint64(p[i*8:])
}
if c.Tree != nil && c.Tree.IsLastNode {
d.isLastNode = true
}
// Process key.
if c.Key != nil {
copy(d.paddedKey[:], c.Key)
d.Write(d.paddedKey[:])
d.isKeyed = true
}
// Save a copy of initialized state.
copy(d.ih[:], d.h[:])
}
// New512 returns a new hash.Hash computing the BLAKE2b 64-byte checksum.
func New512() hash.Hash {
d := new(digest)
d.initialize(defaultConfig)
return d
}
// New256 returns a new hash.Hash computing the BLAKE2b 32-byte checksum.
func New256() hash.Hash {
d := new(digest)
d.initialize(config256)
return d
}
// NewMAC returns a new hash.Hash computing BLAKE2b prefix-
// Message Authentication Code of the given size in bytes
// (up to 64) with the given key (up to 64 bytes in length).
func NewMAC(outBytes uint8, key []byte) hash.Hash {
d, err := New(&Config{Size: outBytes, Key: key})
if err != nil {
panic(err.Error())
}
return d
}
// Reset resets the state of digest to the initial state
// after configuration and keying.
func (d *digest) Reset() {
copy(d.h[:], d.ih[:])
d.t[0] = 0
d.t[1] = 0
d.f[0] = 0
d.f[1] = 0
d.nx = 0
if d.isKeyed {
d.Write(d.paddedKey[:])
}
}
// Size returns the digest size in bytes.
func (d *digest) Size() int { return int(d.size) }
// BlockSize returns the algorithm block size in bytes.
func (d *digest) BlockSize() int { return BlockSize }
func (d *digest) Write(p []byte) (nn int, err error) {
nn = len(p)
left := BlockSize - d.nx
if len(p) > left {
// Process buffer.
copy(d.x[d.nx:], p[:left])
p = p[left:]
compress(d, d.x[:])
d.nx = 0
}
// Process full blocks except for the last one.
if len(p) > BlockSize {
n := len(p) &^ (BlockSize - 1)
if n == len(p) {
n -= BlockSize
}
compress(d, p[:n])
p = p[n:]
}
// Fill buffer.
d.nx += copy(d.x[d.nx:], p)
return
}
// Sum returns the calculated checksum.
func (d *digest) Sum(in []byte) []byte {
// Make a copy of d so that caller can keep writing and summing.
d0 := *d
hash := d0.checkSum()
return append(in, hash[:d0.size]...)
}
func (d *digest) checkSum() [Size]byte {
// Do not create unnecessary copies of the key.
if d.isKeyed {
for i := 0; i < len(d.paddedKey); i++ {
d.paddedKey[i] = 0
}
}
dec := BlockSize - uint64(d.nx)
if d.t[0] < dec {
d.t[1]--
}
d.t[0] -= dec
// Pad buffer with zeros.
for i := d.nx; i < len(d.x); i++ {
d.x[i] = 0
}
// Set last block flag.
d.f[0] = 0xffffffffffffffff
if d.isLastNode {
d.f[1] = 0xffffffffffffffff
}
// Compress last block.
compress(d, d.x[:])
var out [Size]byte
j := 0
for _, s := range d.h[:(d.size-1)/8+1] {
out[j+0] = byte(s >> 0)
out[j+1] = byte(s >> 8)
out[j+2] = byte(s >> 16)
out[j+3] = byte(s >> 24)
out[j+4] = byte(s >> 32)
out[j+5] = byte(s >> 40)
out[j+6] = byte(s >> 48)
out[j+7] = byte(s >> 56)
j += 8
}
return out
}
// Sum512 returns a 64-byte BLAKE2b hash of data.
func Sum512(data []byte) [64]byte {
var d digest
d.initialize(defaultConfig)
d.Write(data)
return d.checkSum()
}
// Sum256 returns a 32-byte BLAKE2b hash of data.
func Sum256(data []byte) (out [32]byte) {
var d digest
d.initialize(config256)
d.Write(data)
sum := d.checkSum()
copy(out[:], sum[:32])
return
}