mirror of
https://github.com/didyouexpectthat/zerotierone.git
synced 2024-11-13 19:50:07 -08:00
121 lines
2.4 KiB
C++
121 lines
2.4 KiB
C++
/*
|
|
* Based on public domain code available at: http://cr.yp.to/snuffle.html
|
|
*
|
|
* This therefore is public domain.
|
|
*/
|
|
|
|
#ifndef ZT_SALSA20_HPP
|
|
#define ZT_SALSA20_HPP
|
|
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "Constants.hpp"
|
|
#include "Utils.hpp"
|
|
|
|
#if (!defined(ZT_SALSA20_SSE)) && (defined(__SSE2__) || defined(__WINDOWS__))
|
|
#define ZT_SALSA20_SSE 1
|
|
#endif
|
|
|
|
#ifdef ZT_SALSA20_SSE
|
|
#include <emmintrin.h>
|
|
#endif // ZT_SALSA20_SSE
|
|
|
|
namespace ZeroTier {
|
|
|
|
/**
|
|
* Salsa20 stream cipher
|
|
*/
|
|
class Salsa20
|
|
{
|
|
public:
|
|
Salsa20() {}
|
|
~Salsa20() { Utils::burn(&_state,sizeof(_state)); }
|
|
|
|
/**
|
|
* XOR d with s
|
|
*
|
|
* This is done efficiently using e.g. SSE if available. It's used when
|
|
* alternative Salsa20 implementations are used in Packet and is here
|
|
* since this is where all the SSE stuff is already included.
|
|
*
|
|
* @param d Destination to XOR
|
|
* @param s Source bytes to XOR with destination
|
|
* @param len Length of s and d
|
|
*/
|
|
static inline void memxor(uint8_t *d,const uint8_t *s,unsigned int len)
|
|
{
|
|
#ifdef ZT_SALSA20_SSE
|
|
while (len >= 16) {
|
|
_mm_storeu_si128(reinterpret_cast<__m128i *>(d),_mm_xor_si128(_mm_loadu_si128(reinterpret_cast<__m128i *>(d)),_mm_loadu_si128(reinterpret_cast<const __m128i *>(s))));
|
|
s += 16;
|
|
d += 16;
|
|
len -= 16;
|
|
}
|
|
#else
|
|
#ifndef ZT_NO_TYPE_PUNNING
|
|
while (len >= 16) {
|
|
(*reinterpret_cast<uint64_t *>(d)) ^= (*reinterpret_cast<const uint64_t *>(s));
|
|
s += 8;
|
|
d += 8;
|
|
(*reinterpret_cast<uint64_t *>(d)) ^= (*reinterpret_cast<const uint64_t *>(s));
|
|
s += 8;
|
|
d += 8;
|
|
len -= 16;
|
|
}
|
|
#endif
|
|
#endif
|
|
while (len--)
|
|
*(d++) ^= *(s++);
|
|
}
|
|
|
|
/**
|
|
* @param key 256-bit (32 byte) key
|
|
* @param iv 64-bit initialization vector
|
|
*/
|
|
Salsa20(const void *key,const void *iv)
|
|
{
|
|
init(key,iv);
|
|
}
|
|
|
|
/**
|
|
* Initialize cipher
|
|
*
|
|
* @param key Key bits
|
|
* @param iv 64-bit initialization vector
|
|
*/
|
|
void init(const void *key,const void *iv);
|
|
|
|
/**
|
|
* Encrypt/decrypt data using Salsa20/12
|
|
*
|
|
* @param in Input data
|
|
* @param out Output buffer
|
|
* @param bytes Length of data
|
|
*/
|
|
void crypt12(const void *in,void *out,unsigned int bytes);
|
|
|
|
/**
|
|
* Encrypt/decrypt data using Salsa20/20
|
|
*
|
|
* @param in Input data
|
|
* @param out Output buffer
|
|
* @param bytes Length of data
|
|
*/
|
|
void crypt20(const void *in,void *out,unsigned int bytes);
|
|
|
|
private:
|
|
union {
|
|
#ifdef ZT_SALSA20_SSE
|
|
__m128i v[4];
|
|
#endif // ZT_SALSA20_SSE
|
|
uint32_t i[16];
|
|
} _state;
|
|
};
|
|
|
|
} // namespace ZeroTier
|
|
|
|
#endif
|