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76 lines
1.7 KiB
76 lines
1.7 KiB
// Copyright 2013 The Go Authors. All rights reserved. |
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// Use of this source code is governed by a BSD-style |
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// license that can be found in the LICENSE file. |
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// Electronic Code Book (ECB) mode. |
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// ECB provides confidentiality by assigning a fixed ciphertext block to each |
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// plaintext block. |
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// See NIST SP 800-38A, pp 08-09 |
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package cipher |
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import ( |
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"crypto/cipher" |
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) |
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type ecb struct { |
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b cipher.Block |
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blockSize int |
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} |
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func newECB(b cipher.Block) *ecb { |
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return &ecb{ |
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b: b, |
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blockSize: b.BlockSize(), |
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} |
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} |
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type ecbEncrypter ecb |
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// NewECBEncrypter returns a BlockMode which encrypts in electronic code book |
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// mode, using the given Block. |
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func NewECBEncrypter(b cipher.Block) cipher.BlockMode { |
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return (*ecbEncrypter)(newECB(b)) |
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} |
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func (x *ecbEncrypter) BlockSize() int { return x.blockSize } |
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func (x *ecbEncrypter) CryptBlocks(dst, src []byte) { |
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if len(src)%x.blockSize != 0 { |
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panic("crypto/cipher: input not full blocks") |
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} |
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if len(dst) < len(src) { |
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panic("crypto/cipher: output smaller than input") |
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} |
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for len(src) > 0 { |
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x.b.Encrypt(dst, src[:x.blockSize]) |
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src = src[x.blockSize:] |
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dst = dst[x.blockSize:] |
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} |
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} |
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type ecbDecrypter ecb |
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// NewECBDecrypter returns a BlockMode which decrypts in electronic code book |
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// mode, using the given Block. |
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func NewECBDecrypter(b cipher.Block) cipher.BlockMode { |
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return (*ecbDecrypter)(newECB(b)) |
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} |
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func (x *ecbDecrypter) BlockSize() int { return x.blockSize } |
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func (x *ecbDecrypter) CryptBlocks(dst, src []byte) { |
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if len(src)%x.blockSize != 0 { |
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panic("crypto/cipher: input not full blocks") |
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} |
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if len(dst) < len(src) { |
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panic("crypto/cipher: output smaller than input") |
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} |
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for len(src) > 0 { |
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x.b.Decrypt(dst, src[:x.blockSize]) |
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src = src[x.blockSize:] |
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dst = dst[x.blockSize:] |
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} |
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}
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