From 38ee83e45b4de7edf89bf9f0ef629eb4c6ad0fa8 Mon Sep 17 00:00:00 2001 From: Christopher Speller Date: Thu, 12 May 2016 23:56:07 -0400 Subject: Moving to glide --- vendor/golang.org/x/crypto/tea/cipher.go | 109 +++++++++++++++++++++++++++++ vendor/golang.org/x/crypto/tea/tea_test.go | 93 ++++++++++++++++++++++++ 2 files changed, 202 insertions(+) create mode 100644 vendor/golang.org/x/crypto/tea/cipher.go create mode 100644 vendor/golang.org/x/crypto/tea/tea_test.go (limited to 'vendor/golang.org/x/crypto/tea') diff --git a/vendor/golang.org/x/crypto/tea/cipher.go b/vendor/golang.org/x/crypto/tea/cipher.go new file mode 100644 index 000000000..9c13d12a2 --- /dev/null +++ b/vendor/golang.org/x/crypto/tea/cipher.go @@ -0,0 +1,109 @@ +// Copyright 2015 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 tea implements the TEA algorithm, as defined in Needham and +// Wheeler's 1994 technical report, “TEA, a Tiny Encryption Algorithm”. See +// http://www.cix.co.uk/~klockstone/tea.pdf for details. + +package tea + +import ( + "crypto/cipher" + "encoding/binary" + "errors" +) + +const ( + // BlockSize is the size of a TEA block, in bytes. + BlockSize = 8 + + // KeySize is the size of a TEA key, in bytes. + KeySize = 16 + + // delta is the TEA key schedule constant. + delta = 0x9e3779b9 + + // numRounds is the standard number of rounds in TEA. + numRounds = 64 +) + +// tea is an instance of the TEA cipher with a particular key. +type tea struct { + key [16]byte + rounds int +} + +// NewCipher returns an instance of the TEA cipher with the standard number of +// rounds. The key argument must be 16 bytes long. +func NewCipher(key []byte) (cipher.Block, error) { + return NewCipherWithRounds(key, numRounds) +} + +// NewCipherWithRounds returns an instance of the TEA cipher with a given +// number of rounds, which must be even. The key argument must be 16 bytes +// long. +func NewCipherWithRounds(key []byte, rounds int) (cipher.Block, error) { + if len(key) != 16 { + return nil, errors.New("tea: incorrect key size") + } + + if rounds&1 != 0 { + return nil, errors.New("tea: odd number of rounds specified") + } + + c := &tea{ + rounds: rounds, + } + copy(c.key[:], key) + + return c, nil +} + +// BlockSize returns the TEA block size, which is eight bytes. It is necessary +// to satisfy the Block interface in the package "crypto/cipher". +func (*tea) BlockSize() int { + return BlockSize +} + +// Encrypt encrypts the 8 byte buffer src using the key in t 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 (t *tea) Encrypt(dst, src []byte) { + e := binary.BigEndian + v0, v1 := e.Uint32(src), e.Uint32(src[4:]) + k0, k1, k2, k3 := e.Uint32(t.key[0:]), e.Uint32(t.key[4:]), e.Uint32(t.key[8:]), e.Uint32(t.key[12:]) + + sum := uint32(0) + delta := uint32(delta) + + for i := 0; i < t.rounds/2; i++ { + sum += delta + v0 += ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1) + v1 += ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3) + } + + e.PutUint32(dst, v0) + e.PutUint32(dst[4:], v1) +} + +// Decrypt decrypts the 8 byte buffer src using the key in t and stores the +// result in dst. +func (t *tea) Decrypt(dst, src []byte) { + e := binary.BigEndian + v0, v1 := e.Uint32(src), e.Uint32(src[4:]) + k0, k1, k2, k3 := e.Uint32(t.key[0:]), e.Uint32(t.key[4:]), e.Uint32(t.key[8:]), e.Uint32(t.key[12:]) + + delta := uint32(delta) + sum := delta * uint32(t.rounds/2) // in general, sum = delta * n + + for i := 0; i < t.rounds/2; i++ { + v1 -= ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3) + v0 -= ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1) + sum -= delta + } + + e.PutUint32(dst, v0) + e.PutUint32(dst[4:], v1) +} diff --git a/vendor/golang.org/x/crypto/tea/tea_test.go b/vendor/golang.org/x/crypto/tea/tea_test.go new file mode 100644 index 000000000..eb98d1e0e --- /dev/null +++ b/vendor/golang.org/x/crypto/tea/tea_test.go @@ -0,0 +1,93 @@ +// Copyright 2015 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 tea + +import ( + "bytes" + "testing" +) + +// A sample test key for when we just want to initialize a cipher +var testKey = []byte{0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF} + +// Test that the block size for tea is correct +func TestBlocksize(t *testing.T) { + c, err := NewCipher(testKey) + if err != nil { + t.Fatalf("NewCipher returned error: %s", err) + } + + if result := c.BlockSize(); result != BlockSize { + t.Errorf("cipher.BlockSize returned %d, but expected %d", result, BlockSize) + } +} + +// Test that invalid key sizes return an error +func TestInvalidKeySize(t *testing.T) { + var key [KeySize + 1]byte + + if _, err := NewCipher(key[:]); err == nil { + t.Errorf("invalid key size %d didn't result in an error.", len(key)) + } + + if _, err := NewCipher(key[:KeySize-1]); err == nil { + t.Errorf("invalid key size %d didn't result in an error.", KeySize-1) + } +} + +// Test Vectors +type teaTest struct { + rounds int + key []byte + plaintext []byte + ciphertext []byte +} + +var teaTests = []teaTest{ + // These were sourced from https://github.com/froydnj/ironclad/blob/master/testing/test-vectors/tea.testvec + { + numRounds, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x41, 0xea, 0x3a, 0x0a, 0x94, 0xba, 0xa9, 0x40}, + }, + { + numRounds, + []byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, + []byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}, + []byte{0x31, 0x9b, 0xbe, 0xfb, 0x01, 0x6a, 0xbd, 0xb2}, + }, + { + 16, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, + []byte{0xed, 0x28, 0x5d, 0xa1, 0x45, 0x5b, 0x33, 0xc1}, + }, +} + +// Test encryption +func TestCipherEncrypt(t *testing.T) { + // Test encryption with standard 64 rounds + for i, test := range teaTests { + c, err := NewCipherWithRounds(test.key, test.rounds) + if err != nil { + t.Fatalf("#%d: NewCipher returned error: %s", i, err) + } + + var ciphertext [BlockSize]byte + c.Encrypt(ciphertext[:], test.plaintext) + + if !bytes.Equal(ciphertext[:], test.ciphertext) { + t.Errorf("#%d: incorrect ciphertext. Got %x, wanted %x", i, ciphertext, test.ciphertext) + } + + var plaintext2 [BlockSize]byte + c.Decrypt(plaintext2[:], ciphertext[:]) + + if !bytes.Equal(plaintext2[:], test.plaintext) { + t.Errorf("#%d: incorrect plaintext. Got %x, wanted %x", i, plaintext2, test.plaintext) + } + } +} -- cgit v1.2.3-1-g7c22