distribution/vendor/golang.org/x/crypto/blowfish/cipher.go
Derek McGowan a685e3fc98
Replace godep with vndr
Vndr has a simpler configuration and allows pointing to forked
packages. Additionally other docker projects are now using
vndr making vendoring in distribution more consistent.

Updates letsencrypt to use fork.
No longer uses sub-vendored packages.

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
2016-11-23 15:07:06 -08:00

91 lines
3 KiB
Go

// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package blowfish implements Bruce Schneier's Blowfish encryption algorithm.
package blowfish // import "golang.org/x/crypto/blowfish"
// The code is a port of Bruce Schneier's C implementation.
// See http://www.schneier.com/blowfish.html.
import "strconv"
// The Blowfish block size in bytes.
const BlockSize = 8
// A Cipher is an instance of Blowfish encryption using a particular key.
type Cipher struct {
p [18]uint32
s0, s1, s2, s3 [256]uint32
}
type KeySizeError int
func (k KeySizeError) Error() string {
return "crypto/blowfish: invalid key size " + strconv.Itoa(int(k))
}
// NewCipher creates and returns a Cipher.
// The key argument should be the Blowfish key, from 1 to 56 bytes.
func NewCipher(key []byte) (*Cipher, error) {
var result Cipher
if k := len(key); k < 1 || k > 56 {
return nil, KeySizeError(k)
}
initCipher(&result)
ExpandKey(key, &result)
return &result, nil
}
// NewSaltedCipher creates a returns a Cipher that folds a salt into its key
// schedule. For most purposes, NewCipher, instead of NewSaltedCipher, is
// sufficient and desirable. For bcrypt compatiblity, the key can be over 56
// bytes.
func NewSaltedCipher(key, salt []byte) (*Cipher, error) {
if len(salt) == 0 {
return NewCipher(key)
}
var result Cipher
if k := len(key); k < 1 {
return nil, KeySizeError(k)
}
initCipher(&result)
expandKeyWithSalt(key, salt, &result)
return &result, nil
}
// BlockSize returns the Blowfish block size, 8 bytes.
// It is necessary to satisfy the Block interface in the
// package "crypto/cipher".
func (c *Cipher) BlockSize() int { return BlockSize }
// Encrypt encrypts the 8-byte buffer src using the key k
// and stores the result in dst.
// Note that for amounts of data larger than a block,
// it is not safe to just call Encrypt on successive blocks;
// instead, use an encryption mode like CBC (see crypto/cipher/cbc.go).
func (c *Cipher) Encrypt(dst, src []byte) {
l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
l, r = encryptBlock(l, r, c)
dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
}
// Decrypt decrypts the 8-byte buffer src using the key k
// and stores the result in dst.
func (c *Cipher) Decrypt(dst, src []byte) {
l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
l, r = decryptBlock(l, r, c)
dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
}
func initCipher(c *Cipher) {
copy(c.p[0:], p[0:])
copy(c.s0[0:], s0[0:])
copy(c.s1[0:], s1[0:])
copy(c.s2[0:], s2[0:])
copy(c.s3[0:], s3[0:])
}