ff5f50c52c
Update to current version of Go library. Update testsuite for removed types. * go-lang.c (go_langhook_init): Omit float_type_size when calling go_create_gogo. * go-c.h: Update declaration of go_create_gogo. From-SVN: r169098
45 lines
885 B
Go
45 lines
885 B
Go
// Copyright 2011 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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// OFB (Output Feedback) Mode.
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package cipher
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type ofb struct {
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b Block
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out []byte
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outUsed int
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}
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// NewOFB returns a Stream that encrypts or decrypts using the block cipher b
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// in output feedback mode. The initialization vector iv's length must be equal
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// to b's block size.
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func NewOFB(b Block, iv []byte) Stream {
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blockSize := b.BlockSize()
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if len(iv) != blockSize {
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return nil
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}
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x := &ofb{
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b: b,
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out: make([]byte, blockSize),
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outUsed: 0,
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}
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b.Encrypt(x.out, iv)
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return x
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}
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func (x *ofb) XORKeyStream(dst, src []byte) {
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for i, s := range src {
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if x.outUsed == len(x.out) {
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x.b.Encrypt(x.out, x.out)
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x.outUsed = 0
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}
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dst[i] = s ^ x.out[x.outUsed]
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x.outUsed++
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}
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}
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