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Diffstat (limited to 'libgo/go/crypto/xtea/block.go')
-rw-r--r--libgo/go/crypto/xtea/block.go66
1 files changed, 0 insertions, 66 deletions
diff --git a/libgo/go/crypto/xtea/block.go b/libgo/go/crypto/xtea/block.go
deleted file mode 100644
index bf5d245..0000000
--- a/libgo/go/crypto/xtea/block.go
+++ /dev/null
@@ -1,66 +0,0 @@
-// Copyright 2009 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.
-
-/*
- Implementation adapted from Needham and Wheeler's paper:
- http://www.cix.co.uk/~klockstone/xtea.pdf
-
- A precalculated look up table is used during encryption/decryption for values that are based purely on the key.
-*/
-
-package xtea
-
-// XTEA is based on 64 rounds.
-const numRounds = 64
-
-// blockToUint32 reads an 8 byte slice into two uint32s.
-// The block is treated as big endian.
-func blockToUint32(src []byte) (uint32, uint32) {
- r0 := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
- r1 := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
- return r0, r1
-}
-
-// uint32ToBlock writes two uint32s into an 8 byte data block.
-// Values are written as big endian.
-func uint32ToBlock(v0, v1 uint32, dst []byte) {
- dst[0] = byte(v0 >> 24)
- dst[1] = byte(v0 >> 16)
- dst[2] = byte(v0 >> 8)
- dst[3] = byte(v0)
- dst[4] = byte(v1 >> 24)
- dst[5] = byte(v1 >> 16)
- dst[6] = byte(v1 >> 8)
- dst[7] = byte(v1 >> 0)
-}
-
-// encryptBlock encrypts a single 8 byte block using XTEA.
-func encryptBlock(c *Cipher, dst, src []byte) {
- v0, v1 := blockToUint32(src)
-
- // Two rounds of XTEA applied per loop
- for i := 0; i < numRounds; {
- v0 += ((v1<<4 ^ v1>>5) + v1) ^ c.table[i]
- i++
- v1 += ((v0<<4 ^ v0>>5) + v0) ^ c.table[i]
- i++
- }
-
- uint32ToBlock(v0, v1, dst)
-}
-
-// decryptBlock decrypt a single 8 byte block using XTEA.
-func decryptBlock(c *Cipher, dst, src []byte) {
- v0, v1 := blockToUint32(src)
-
- // Two rounds of XTEA applied per loop
- for i := numRounds; i > 0; {
- i--
- v1 -= ((v0<<4 ^ v0>>5) + v0) ^ c.table[i]
- i--
- v0 -= ((v1<<4 ^ v1>>5) + v1) ^ c.table[i]
- }
-
- uint32ToBlock(v0, v1, dst)
-}