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ChaCha stream cipher

This commit is contained in:
Rhys Weatherley 2015-01-02 08:51:46 +10:00
parent 46fe4e52fd
commit 07a47cdcf1
7 changed files with 928 additions and 2 deletions

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* AES192, or AES256 to create an AES block cipher with a specific
* key size.
*
* \note This AES implementation does not have constant cache behaviour due
* to the use of table lookups. It may not be safe to use this implementation
* in an environment where the attacker can observe the timing of encryption
* and decryption operations. Unless AES compatibility is required,
* it is recommended that the ChaCha stream cipher be used instead.
*
* Reference: http://en.wikipedia.org/wiki/Advanced_Encryption_Standard
*
* \sa AES128, AES192, AES256
* \sa ChaCha, AES128, AES192, AES256
*/
// AES S-box (http://en.wikipedia.org/wiki/Rijndael_S-box)

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* \note While fast and small on 8-bit platforms, Arcfour is a very weak
* algorithm when used incorrectly. Security can be improved slightly using
* drop() and good key generation. Never reuse the same key with Arcfour.
* ChaCha will almost always be a better option than Arcfour.
*
* The default key size is 128 bits, but any key size between 40 and
* 256 bits (5 to 32 bytes) can be used with setKey().
@ -41,7 +42,7 @@
*
* Reference: http://en.wikipedia.org/wiki/RC4
*
* \sa Cipher
* \sa ChaCha
*/
/**

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libraries/Crypto/ChaCha.cpp Normal file
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/*
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include "ChaCha.h"
#include "Crypto.h"
#include "RotateUtil.h"
#include "EndianUtil.h"
#include <string.h>
/**
* \class ChaCha ChaCha.h <ChaCha.h>
* \brief ChaCha stream cipher.
*
* ChaCha is a stream cipher that takes a key, an 8-byte nonce/IV, and a
* counter and hashes them to generate a keystream to XOR with the plaintext.
* Variations on the ChaCha cipher use 8, 12, or 20 rounds of hashing
* operations with either 128-bit or 256-bit keys.
*
* Reference: http://cr.yp.to/chacha.html
*/
/**
* \brief Constructs a new ChaCha stream cipher.
*
* \param numRounds Number of encryption rounds to use; usually 8, 12, or 20.
*/
ChaCha::ChaCha(uint8_t numRounds)
: rounds(numRounds)
, posn(64)
{
}
ChaCha::~ChaCha()
{
clean(block);
clean(stream);
}
size_t ChaCha::keySize() const
{
// Default key size is 128-bit, but any key size is allowed.
return 16;
}
size_t ChaCha::ivSize() const
{
// We return 8 but we also support 12-byte nonces in setIV().
return 8;
}
/**
* \fn uint8_t ChaCha::numRounds() const
* \brief Returns the number of encryption rounds; usually 8, 12, or 20.
*
* \sa setNumRounds()
*/
/**
* \fn void ChaCha::setNumRounds(uint8_t numRounds)
* \brief Sets the number of encryption rounds.
*
* \param numRounds The number of encryption rounds; usually 8, 12, or 20.
*
* \sa numRounds()
*/
bool ChaCha::setKey(const uint8_t *key, size_t len)
{
static const char tag128[] = "expand 16-byte k";
static const char tag256[] = "expand 32-byte k";
if (len <= 16) {
memcpy(block, tag128, 16);
memcpy(block + 16, key, len);
memcpy(block + 32, key, len);
if (len < 16) {
memset(block + 16 + len, 0, 16 - len);
memset(block + 32 + len, 0, 16 - len);
}
} else {
if (len > 32)
len = 32;
memcpy(block, tag256, 16);
memcpy(block + 16, key, len);
if (len < 32)
memset(block + 16 + len, 0, 32 - len);
}
posn = 64;
return true;
}
bool ChaCha::setIV(const uint8_t *iv, size_t len)
{
// From draft-nir-cfrg-chacha20-poly1305-04.txt, we can use either
// 64-bit or 96-bit nonces. The 96-bit nonce consists of the high
// word of the counter prepended to a regular 64-bit nonce for ChaCha.
if (len == 8) {
memset(block + 48, 0, 8);
memcpy(block + 56, iv, len);
posn = 64;
return true;
} else if (len == 12) {
memset(block + 48, 0, 4);
memcpy(block + 52, iv, len);
posn = 64;
return true;
} else {
return false;
}
}
/**
* \brief Sets the starting counter for encryption.
*
* \param counter A 4-byte or 8-byte value to use for the starting counter
* instead of the default value of zero.
* \param len The length of the counter, which must be 4 or 8.
* \return Returns false if \a len is not 4 or 8.
*
* This function must be called after setIV() and before the first call
* to encrypt(). It is used to specify a different starting value than
* zero for the counter portion of the hash input.
*
* \sa setIV()
*/
bool ChaCha::setCounter(const uint8_t *counter, size_t len)
{
// Normally both the IV and the counter are 8 bytes in length.
// However, if the IV was 12 bytes, then a 4 byte counter can be used.
if (len == 4 || len == 8) {
memcpy(block + 48, counter, len);
posn = 64;
return true;
} else {
return false;
}
}
void ChaCha::encrypt(uint8_t *output, const uint8_t *input, size_t len)
{
while (len > 0) {
if (posn >= 64) {
// Generate a new encrypted counter block.
hashCore((uint32_t *)stream, (const uint32_t *)block, rounds);
posn = 0;
// Increment the counter, taking care not to reveal
// any timing information about the starting value.
// We iterate through the entire counter region even
// if we could stop earlier because a byte is non-zero.
uint16_t temp = 1;
uint8_t index = 48;
while (index < 56) {
temp += block[index];
block[index] = (uint8_t)temp;
temp >>= 8;
++index;
}
}
uint8_t templen = 64 - posn;
if (templen > len)
templen = len;
len -= templen;
while (templen > 0) {
*output++ = *input++ ^ stream[posn++];
--templen;
}
}
}
void ChaCha::decrypt(uint8_t *output, const uint8_t *input, size_t len)
{
encrypt(output, input, len);
}
void ChaCha::clear()
{
clean(block);
clean(stream);
posn = 64;
}
// On AVR it is faster to rotate left by 16 bits and then right by 4 bits
// one at a time than to rotate left by 12 bits in a single step.
#define leftRotate12(a) \
(__extension__ ({ \
uint32_t temp = (a); \
temp = (temp << 16) | (temp >> 16); \
temp = rightRotate(temp, 1); \
temp = rightRotate(temp, 1); \
temp = rightRotate(temp, 1); \
rightRotate(temp, 1); \
}))
// Perform a ChaCha quarter round operation.
#define quarterRound(a, b, c, d) \
do { \
uint32_t _b = (b); \
uint32_t _a = (a) + _b; \
uint32_t _d = leftRotate((d) ^ _a, 16); \
uint32_t _c = (c) + _d; \
_b = leftRotate12(_b ^ _c); \
_a += _b; \
(d) = _d = leftRotate(_d ^ _a, 8); \
_c += _d; \
(a) = _a; \
(b) = leftRotate7(_b ^ _c); \
(c) = _c; \
} while (0)
/**
* \brief Executes the ChaCha hash core on an input memory block.
*
* \param output Output memory block, must be at least 16 words in length
* and must not overlap with \a input.
* \param input Input memory block, must be at least 16 words in length.
* \param rounds Number of ChaCha rounds to perform; usually 8, 12, or 20.
*
* This function is provided for the convenience of applications that need
* access to the ChaCha hash core without the higher-level processing that
* turns the core into a stream cipher.
*/
void ChaCha::hashCore(uint32_t *output, const uint32_t *input, uint8_t rounds)
{
uint8_t posn;
// Copy the input buffer to the output prior to the first round
// and convert from little-endian to host byte order.
for (posn = 0; posn < 16; ++posn)
output[posn] = le32toh(input[posn]);
// Perform the ChaCha rounds in sets of two.
for (; rounds >= 2; rounds -= 2) {
// Column round.
quarterRound(output[0], output[4], output[8], output[12]);
quarterRound(output[1], output[5], output[9], output[13]);
quarterRound(output[2], output[6], output[10], output[14]);
quarterRound(output[3], output[7], output[11], output[15]);
// Diagonal round.
quarterRound(output[0], output[5], output[10], output[15]);
quarterRound(output[1], output[6], output[11], output[12]);
quarterRound(output[2], output[7], output[8], output[13]);
quarterRound(output[3], output[4], output[9], output[14]);
}
// Add the original input to the final output, convert back to
// little-endian, and return the result.
for (posn = 0; posn < 16; ++posn)
output[posn] = htole32(output[posn] + le32toh(input[posn]));
}

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libraries/Crypto/ChaCha.h Normal file
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/*
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef CRYPTO_CHACHA_h
#define CRYPTO_CHACHA_h
#include "Cipher.h"
class ChaCha : public Cipher
{
public:
explicit ChaCha(uint8_t numRounds = 20);
virtual ~ChaCha();
size_t keySize() const;
size_t ivSize() const;
uint8_t numRounds() const { return rounds; }
void setNumRounds(uint8_t numRounds) { rounds = numRounds; }
bool setKey(const uint8_t *key, size_t len);
bool setIV(const uint8_t *iv, size_t len);
bool setCounter(const uint8_t *counter, size_t len);
void encrypt(uint8_t *output, const uint8_t *input, size_t len);
void decrypt(uint8_t *output, const uint8_t *input, size_t len);
void clear();
static void hashCore(uint32_t *output, const uint32_t *input, uint8_t rounds);
private:
uint8_t block[64];
uint8_t stream[64];
uint8_t rounds;
uint8_t posn;
};
#endif

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/*
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef CRYPTO_ENDIANUTIL_H
#define CRYPTO_ENDIANUTIL_H
#include <inttypes.h>
// CPU is assumed to be little endian. Edit this file if you
// need to port this library to a big endian CPU.
#define htole32(x) (x)
#define le32toh(x) (x)
#define htobe32(x) \
(__extension__ ({ \
uint32_t _temp = (x); \
((_temp >> 24) & 0x000000FF) | \
((_temp >> 8) & 0x0000FF00) | \
((_temp << 8) & 0x00FF0000) | \
((_temp << 24) & 0xFF000000); \
}))
#define be32toh(x) (htobe32((x)))
#endif

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/*
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef CRYPTO_ROTATEUTIL_H
#define CRYPTO_ROTATEUTIL_H
#include <inttypes.h>
// Rotation functions that are optimised for best performance on AVR.
// The most efficient rotations are where the number of bits is 1 or a
// multiple of 8, so we compose the efficient rotations to produce all
// other rotation counts of interest. All macros below assume arguments
// of 32 bits in size.
// Generic left rotate - best performance when "bits" is 1 or a multiple of 8.
#define leftRotate(a, bits) \
(__extension__ ({ \
uint32_t _temp = (a); \
(_temp << (bits)) | (_temp >> (32 - (bits))); \
}))
// Generic right rotate - best performance when "bits" is 1 or a multiple of 8.
#define rightRotate(a, bits) \
(__extension__ ({ \
uint32_t _temp = (a); \
(_temp >> (bits)) | (_temp << (32 - (bits))); \
}))
// Left rotate by 1.
#define leftRotate1(a) (leftRotate((a), 1))
// Left rotate by 2.
#define leftRotate2(a) (leftRotate(leftRotate((a), 1), 1))
// Left rotate by 3.
#define leftRotate3(a) (leftRotate(leftRotate(leftRotate((a), 1), 1), 1))
// Left rotate by 4.
#define leftRotate4(a) (leftRotate(leftRotate(leftRotate(leftRotate((a), 1), 1), 1), 1))
// Left rotate by 5: Rotate left by 8, then right by 3.
#define leftRotate5(a) (rightRotate(rightRotate(rightRotate(leftRotate((a), 8), 1), 1), 1))
// Left rotate by 6: Rotate left by 8, then right by 2.
#define leftRotate6(a) (rightRotate(rightRotate(leftRotate((a), 8), 1), 1))
// Left rotate by 7: Rotate left by 8, then right by 1.
#define leftRotate7(a) (rightRotate(leftRotate((a), 8), 1))
// Left rotate by 8.
#define leftRotate8(a) (leftRotate((a), 8))
// Left rotate by 9: Rotate left by 8, then left by 1.
#define leftRotate9(a) (leftRotate(leftRotate((a), 8), 1))
// Left rotate by 10: Rotate left by 8, then left by 2.
#define leftRotate10(a) (leftRotate(leftRotate(leftRotate((a), 8), 1), 1))
// Left rotate by 11: Rotate left by 8, then left by 3.
#define leftRotate11(a) (leftRotate(leftRotate(leftRotate(leftRotate((a), 8), 1), 1), 1))
// Left rotate by 12: Rotate left by 8, then left by 4.
#define leftRotate12(a) (leftRotate(leftRotate(leftRotate(leftRotate(leftRotate((a), 8), 1), 1), 1), 1))
// Left rotate by 13: Rotate left by 16, then right by 3.
#define leftRotate13(a) (rightRotate(rightRotate(rightRotate(leftRotate((a), 16), 1), 1), 1))
// Left rotate by 14: Rotate left by 16, then right by 2.
#define leftRotate14(a) (rightRotate(rightRotate(leftRotate((a), 16), 1), 1))
// Left rotate by 15: Rotate left by 16, then right by 1.
#define leftRotate15(a) (rightRotate(leftRotate((a), 16), 1))
// Left rotate by 16.
#define leftRotate16(a) (leftRotate((a), 16))
// Left rotate by 17: Rotate left by 16, then left by 1.
#define leftRotate17(a) (leftRotate(leftRotate((a), 16), 1))
// Left rotate by 18: Rotate left by 16, then left by 2.
#define leftRotate18(a) (leftRotate(leftRotate(leftRotate((a), 16), 1), 1))
// Left rotate by 19: Rotate left by 16, then left by 3.
#define leftRotate19(a) (leftRotate(leftRotate(leftRotate(leftRotate((a), 16), 1), 1), 1))
// Left rotate by 20: Rotate left by 16, then left by 4.
#define leftRotate20(a) (leftRotate(leftRotate(leftRotate(leftRotate(leftRotate((a), 16), 1), 1), 1), 1))
// Left rotate by 21: Rotate left by 24, then right by 3.
#define leftRotate21(a) (rightRotate(rightRotate(rightRotate(leftRotate((a), 24), 1), 1), 1))
// Left rotate by 22: Rotate left by 24, then right by 2.
#define leftRotate22(a) (rightRotate(rightRotate(leftRotate((a), 24), 1), 1))
// Left rotate by 23: Rotate left by 24, then right by 1.
#define leftRotate23(a) (rightRotate(leftRotate((a), 24), 1))
// Left rotate by 24.
#define leftRotate24(a) (leftRotate((a), 24))
// Left rotate by 25: Rotate left by 24, then left by 1.
#define leftRotate25(a) (leftRotate(leftRotate((a), 24), 1))
// Left rotate by 26: Rotate left by 24, then left by 2.
#define leftRotate26(a) (leftRotate(leftRotate(leftRotate((a), 24), 1), 1))
// Left rotate by 27: Rotate left by 24, then left by 3.
#define leftRotate27(a) (leftRotate(leftRotate(leftRotate(leftRotate((a), 24), 1), 1), 1))
// Left rotate by 28: Rotate right by 4.
#define leftRotate28(a) (rightRotate(rightRotate(rightRotate(rightRotate((a), 1), 1), 1), 1))
// Left rotate by 29: Rotate right by 3.
#define leftRotate29(a) (rightRotate(rightRotate(rightRotate((a), 1), 1), 1))
// Left rotate by 30: Rotate right by 2.
#define leftRotate30(a) (rightRotate(rightRotate((a), 1), 1))
// Left rotate by 31: Rotate right by 1.
#define leftRotate31(a) (rightRotate((a), 1))
// Define the right rotations in terms of left rotations.
#define rightRotate1(a) (leftRotate31((a)))
#define rightRotate2(a) (leftRotate30((a)))
#define rightRotate3(a) (leftRotate29((a)))
#define rightRotate4(a) (leftRotate28((a)))
#define rightRotate5(a) (leftRotate27((a)))
#define rightRotate6(a) (leftRotate26((a)))
#define rightRotate7(a) (leftRotate25((a)))
#define rightRotate8(a) (leftRotate24((a)))
#define rightRotate9(a) (leftRotate23((a)))
#define rightRotate10(a) (leftRotate22((a)))
#define rightRotate11(a) (leftRotate21((a)))
#define rightRotate12(a) (leftRotate20((a)))
#define rightRotate13(a) (leftRotate19((a)))
#define rightRotate14(a) (leftRotate18((a)))
#define rightRotate15(a) (leftRotate17((a)))
#define rightRotate16(a) (leftRotate16((a)))
#define rightRotate17(a) (leftRotate15((a)))
#define rightRotate18(a) (leftRotate14((a)))
#define rightRotate19(a) (leftRotate13((a)))
#define rightRotate20(a) (leftRotate12((a)))
#define rightRotate21(a) (leftRotate11((a)))
#define rightRotate22(a) (leftRotate10((a)))
#define rightRotate23(a) (leftRotate9((a)))
#define rightRotate24(a) (leftRotate8((a)))
#define rightRotate25(a) (leftRotate7((a)))
#define rightRotate26(a) (leftRotate6((a)))
#define rightRotate27(a) (leftRotate5((a)))
#define rightRotate28(a) (leftRotate4((a)))
#define rightRotate29(a) (leftRotate3((a)))
#define rightRotate30(a) (leftRotate2((a)))
#define rightRotate31(a) (leftRotate1((a)))
#endif

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/*
* Copyright (C) 2015 Southern Storm Software, Pty Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
/*
This example runs tests on the ChaCha implementation to verify correct behaviour.
*/
#include <Crypto.h>
#include <ChaCha.h>
#include <string.h>
#define MAX_PLAINTEXT_SIZE 64
#define MAX_CIPHERTEXT_SIZE 64
struct TestVector
{
const char *name;
byte key[32];
size_t keySize;
uint8_t rounds;
byte plaintext[MAX_PLAINTEXT_SIZE];
byte ciphertext[MAX_CIPHERTEXT_SIZE];
byte iv[8];
byte counter[8];
size_t size;
};
// Use the test vectors from section 9 of the Salsa20 specification,
// http://cr.yp.to/snuffle/spec.pdf, but modify the ciphertext to
// the expected output from ChaCha20/12/8. Unfortunately the ChaCha
// specification doesn't contain test vectors - these were generated
// using the reference implementation from http://cr.yp.to/chacha.html.
static TestVector const testVectorChaCha20_128 = {
.name = "ChaCha20 128-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
.keySize = 16,
.rounds = 20,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0x1C, 0x91, 0xE7, 0x99, 0x71, 0xC0, 0x1C, 0x2A,
0xEC, 0xE9, 0x24, 0x35, 0xB1, 0x6E, 0xBF, 0xFD,
0x33, 0x05, 0xCC, 0x17, 0x24, 0x9D, 0x66, 0xA7,
0xA0, 0xCA, 0xB8, 0x36, 0x03, 0xA6, 0x9D, 0x93,
0x9A, 0x4C, 0x10, 0x40, 0xD9, 0x2A, 0x86, 0x78,
0x3A, 0xAD, 0x71, 0x87, 0x55, 0x9F, 0x5B, 0x9A,
0x68, 0x52, 0xA0, 0xAD, 0x59, 0xAE, 0x04, 0x10,
0x25, 0x74, 0x5C, 0x05, 0x62, 0x78, 0xF4, 0x8A},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
static TestVector const testVectorChaCha20_256 = {
.name = "ChaCha20 256-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210,
211, 212, 213, 214, 215, 216},
.keySize = 32,
.rounds = 20,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0x2A, 0x7E, 0x73, 0xC2, 0x2A, 0xE5, 0xCF, 0x4E,
0x21, 0x75, 0xB1, 0x26, 0x38, 0x3F, 0x60, 0x84,
0x11, 0x25, 0xFC, 0xAD, 0xFD, 0x16, 0x54, 0xF2,
0xD7, 0x8C, 0x5D, 0x49, 0x8D, 0x96, 0xBE, 0x15,
0xC9, 0x00, 0x12, 0x09, 0x14, 0x43, 0x2D, 0x6D,
0x64, 0x33, 0x88, 0xA6, 0x16, 0x39, 0x86, 0xFD,
0xD8, 0x85, 0x4D, 0x76, 0x42, 0xEC, 0x0A, 0x0C,
0x8A, 0xF2, 0x99, 0x2E, 0x54, 0xAE, 0xB4, 0xD9},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
static TestVector const testVectorChaCha12_128 = {
.name = "ChaCha12 128-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
.keySize = 16,
.rounds = 12,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0xCB, 0xC1, 0xCF, 0x63, 0xE8, 0xD0, 0x62, 0x83,
0xFC, 0x12, 0x87, 0x8C, 0x62, 0x09, 0x5B, 0xF8,
0x84, 0x93, 0x30, 0xC6, 0xE6, 0x26, 0x87, 0x99,
0xB0, 0xD9, 0xC1, 0xE1, 0xD7, 0x58, 0xCA, 0x05,
0xFE, 0x46, 0x40, 0xD1, 0xDC, 0x14, 0x68, 0x3C,
0xFF, 0x25, 0xF7, 0x70, 0x5F, 0xBF, 0x37, 0xC5,
0x29, 0x8F, 0x3C, 0x55, 0x74, 0xDF, 0xF7, 0x49,
0x8D, 0xD8, 0xE9, 0xBA, 0x5D, 0xF1, 0x9F, 0xA5},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
static TestVector const testVectorChaCha12_256 = {
.name = "ChaCha12 256-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210,
211, 212, 213, 214, 215, 216},
.keySize = 32,
.rounds = 12,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0xB8, 0x49, 0xD4, 0x70, 0xE0, 0xFF, 0x57, 0x12,
0x95, 0xBF, 0xD9, 0xCD, 0x26, 0xFD, 0x4D, 0x6E,
0x70, 0xA2, 0xBC, 0x58, 0x63, 0xF6, 0x2C, 0xC3,
0xC7, 0x1C, 0x9B, 0x1A, 0x54, 0xDC, 0xF9, 0xF8,
0xFD, 0x59, 0xEA, 0xC9, 0xC3, 0x10, 0xA1, 0xDE,
0xD1, 0x53, 0x84, 0xD6, 0x8D, 0xC6, 0x61, 0x09,
0x2E, 0x62, 0x14, 0xC5, 0x77, 0x4B, 0x6B, 0x5B,
0x0D, 0x35, 0xE6, 0x17, 0x41, 0x51, 0xA6, 0xA4},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
static TestVector const testVectorChaCha8_128 = {
.name = "ChaCha8 128-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16},
.keySize = 16,
.rounds = 8,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0x76, 0x42, 0x84, 0xB4, 0x87, 0x1F, 0x54, 0xAE,
0x33, 0xBF, 0x79, 0x3C, 0xE2, 0x78, 0x5B, 0x4D,
0xE7, 0x90, 0xF3, 0x8C, 0xB8, 0xF4, 0xA1, 0x56,
0x87, 0x8B, 0x54, 0x06, 0xBE, 0x5A, 0x1B, 0x1C,
0x30, 0x31, 0xD3, 0xCD, 0x90, 0x34, 0xC8, 0x93,
0x2C, 0x0A, 0x5E, 0xC9, 0x4A, 0x1A, 0x66, 0x4C,
0x28, 0x94, 0xA9, 0x61, 0xBB, 0xB4, 0xF0, 0x2D,
0x59, 0x73, 0x9F, 0xC9, 0xF1, 0xF0, 0x66, 0x05},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
static TestVector const testVectorChaCha8_256 = {
.name = "ChaCha8 256-bit",
.key = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
201, 202, 203, 204, 205, 206, 207, 208, 209, 210,
211, 212, 213, 214, 215, 216},
.keySize = 32,
.rounds = 8,
.plaintext = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
.ciphertext = {0x38, 0x0F, 0x75, 0xD6, 0x32, 0xF8, 0xBB, 0x2C,
0x44, 0x81, 0xF4, 0x27, 0x90, 0xB8, 0xAA, 0xE3,
0x09, 0xD1, 0xB9, 0x55, 0xC2, 0xF5, 0x85, 0x27,
0xBB, 0x8F, 0x43, 0x00, 0x68, 0x2B, 0x2A, 0x1B,
0x7A, 0xC1, 0x5B, 0xC3, 0xA3, 0xFF, 0x29, 0xC9,
0xD2, 0x95, 0x98, 0xF6, 0x3C, 0xAC, 0x9B, 0x2C,
0xA3, 0xF1, 0x40, 0x1E, 0xFA, 0x7C, 0xAC, 0xA3,
0xB1, 0x61, 0x27, 0x50, 0xBB, 0x03, 0x24, 0x36},
.iv = {101,102,103,104,105,106,107,108},
.counter = {109, 110, 111, 112, 113, 114, 115, 116},
.size = 64
};
ChaCha chacha;
byte buffer[128];
bool testCipher_N(ChaCha *cipher, const struct TestVector *test, size_t inc)
{
byte output[MAX_CIPHERTEXT_SIZE];
size_t posn, len;
cipher->clear();
if (!cipher->setKey(test->key, test->keySize)) {
Serial.print("setKey ");
return false;
}
if (!cipher->setIV(test->iv, cipher->ivSize())) {
Serial.print("setIV ");
return false;
}
if (!cipher->setCounter(test->counter, 8)) {
Serial.print("setCounter ");
return false;
}
memset(output, 0xBA, sizeof(output));
for (posn = 0; posn < test->size; posn += inc) {
len = test->size - posn;
if (len > inc)
len = inc;
cipher->encrypt(output + posn, test->plaintext + posn, len);
}
if (memcmp(output, test->ciphertext, test->size) != 0) {
Serial.print(output[0], HEX);
Serial.print("->");
Serial.print(test->ciphertext[0], HEX);
return false;
}
cipher->setKey(test->key, test->keySize);
cipher->setIV(test->iv, cipher->ivSize());
cipher->setCounter(test->counter, 8);
for (posn = 0; posn < test->size; posn += inc) {
len = test->size - posn;
if (len > inc)
len = inc;
cipher->decrypt(output + posn, test->ciphertext + posn, len);
}
if (memcmp(output, test->plaintext, test->size) != 0)
return false;
return true;
}
void testCipher(ChaCha *cipher, const struct TestVector *test)
{
bool ok;
Serial.print(test->name);
Serial.print(" ... ");
cipher->setNumRounds(test->rounds);
ok = testCipher_N(cipher, test, test->size);
ok &= testCipher_N(cipher, test, 1);
ok &= testCipher_N(cipher, test, 2);
ok &= testCipher_N(cipher, test, 5);
ok &= testCipher_N(cipher, test, 8);
ok &= testCipher_N(cipher, test, 13);
ok &= testCipher_N(cipher, test, 16);
if (ok)
Serial.println("Passed");
else
Serial.println("Failed");
}
void perfCipherEncrypt(ChaCha *cipher, const struct TestVector *test)
{
unsigned long start;
unsigned long elapsed;
int count;
Serial.print(test->name);
Serial.print(" Encrypt ... ");
cipher->setNumRounds(test->rounds);
cipher->setKey(test->key, test->keySize);
cipher->setIV(test->iv, cipher->ivSize());
start = micros();
for (count = 0; count < 500; ++count) {
cipher->encrypt(buffer, buffer, sizeof(buffer));
}
elapsed = micros() - start;
Serial.print(elapsed / (sizeof(buffer) * 500.0));
Serial.print("us per byte, ");
Serial.print((sizeof(buffer) * 500.0 * 1000000.0) / elapsed);
Serial.println(" bytes per second");
}
void perfCipherDecrypt(ChaCha *cipher, const struct TestVector *test)
{
unsigned long start;
unsigned long elapsed;
int count;
Serial.print(test->name);
Serial.print(" Decrypt ... ");
cipher->setNumRounds(test->rounds);
cipher->setKey(test->key, test->keySize);
cipher->setIV(test->iv, cipher->ivSize());
start = micros();
for (count = 0; count < 500; ++count) {
cipher->decrypt(buffer, buffer, sizeof(buffer));
}
elapsed = micros() - start;
Serial.print(elapsed / (sizeof(buffer) * 500.0));
Serial.print("us per byte, ");
Serial.print((sizeof(buffer) * 500.0 * 1000000.0) / elapsed);
Serial.println(" bytes per second");
}
void perfCipher(ChaCha *cipher, const struct TestVector *test)
{
perfCipherEncrypt(cipher, test);
perfCipherDecrypt(cipher, test);
}
void setup()
{
Serial.begin(9600);
Serial.println();
Serial.println("Test Vectors:");
testCipher(&chacha, &testVectorChaCha20_128);
testCipher(&chacha, &testVectorChaCha20_256);
testCipher(&chacha, &testVectorChaCha12_128);
testCipher(&chacha, &testVectorChaCha12_256);
testCipher(&chacha, &testVectorChaCha8_128);
testCipher(&chacha, &testVectorChaCha8_256);
Serial.println();
Serial.println("Performance Tests:");
perfCipher(&chacha, &testVectorChaCha20_128);
perfCipher(&chacha, &testVectorChaCha20_256);
perfCipher(&chacha, &testVectorChaCha12_128);
perfCipher(&chacha, &testVectorChaCha12_256);
perfCipher(&chacha, &testVectorChaCha8_128);
perfCipher(&chacha, &testVectorChaCha8_256);
}
void loop()
{
}