mirror of
https://github.com/zerotier/ZeroTierOne.git
synced 2024-12-27 16:28:52 +00:00
126 lines
2.8 KiB
C++
126 lines
2.8 KiB
C++
/*
|
|
20080912
|
|
D. J. Bernstein
|
|
Public domain.
|
|
*/
|
|
|
|
#include "Constants.hpp"
|
|
#include "Poly1305.hpp"
|
|
|
|
#ifdef __WINDOWS__
|
|
#pragma warning(disable: 4146)
|
|
#endif
|
|
|
|
namespace ZeroTier {
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
|
|
static inline void add(unsigned int h[17],const unsigned int c[17])
|
|
{
|
|
unsigned int j;
|
|
unsigned int u;
|
|
u = 0;
|
|
for (j = 0;j < 17;++j) { u += h[j] + c[j]; h[j] = u & 255; u >>= 8; }
|
|
}
|
|
|
|
static inline void squeeze(unsigned int h[17])
|
|
{
|
|
unsigned int j;
|
|
unsigned int u;
|
|
u = 0;
|
|
for (j = 0;j < 16;++j) { u += h[j]; h[j] = u & 255; u >>= 8; }
|
|
u += h[16]; h[16] = u & 3;
|
|
u = 5 * (u >> 2);
|
|
for (j = 0;j < 16;++j) { u += h[j]; h[j] = u & 255; u >>= 8; }
|
|
u += h[16]; h[16] = u;
|
|
}
|
|
|
|
static const unsigned int minusp[17] = {
|
|
5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 252
|
|
} ;
|
|
|
|
static inline void freeze(unsigned int h[17])
|
|
{
|
|
unsigned int horig[17];
|
|
unsigned int j;
|
|
unsigned int negative;
|
|
for (j = 0;j < 17;++j) horig[j] = h[j];
|
|
add(h,minusp);
|
|
negative = -(h[16] >> 7);
|
|
for (j = 0;j < 17;++j) h[j] ^= negative & (horig[j] ^ h[j]);
|
|
}
|
|
|
|
static inline void mulmod(unsigned int h[17],const unsigned int r[17])
|
|
{
|
|
unsigned int hr[17];
|
|
unsigned int i;
|
|
unsigned int j;
|
|
unsigned int u;
|
|
|
|
for (i = 0;i < 17;++i) {
|
|
u = 0;
|
|
for (j = 0;j <= i;++j) u += h[j] * r[i - j];
|
|
for (j = i + 1;j < 17;++j) u += 320 * h[j] * r[i + 17 - j];
|
|
hr[i] = u;
|
|
}
|
|
for (i = 0;i < 17;++i) h[i] = hr[i];
|
|
squeeze(h);
|
|
}
|
|
|
|
static inline int crypto_onetimeauth(unsigned char *out,const unsigned char *in,unsigned long long inlen,const unsigned char *k)
|
|
{
|
|
unsigned int j;
|
|
unsigned int r[17];
|
|
unsigned int h[17];
|
|
unsigned int c[17];
|
|
|
|
r[0] = k[0];
|
|
r[1] = k[1];
|
|
r[2] = k[2];
|
|
r[3] = k[3] & 15;
|
|
r[4] = k[4] & 252;
|
|
r[5] = k[5];
|
|
r[6] = k[6];
|
|
r[7] = k[7] & 15;
|
|
r[8] = k[8] & 252;
|
|
r[9] = k[9];
|
|
r[10] = k[10];
|
|
r[11] = k[11] & 15;
|
|
r[12] = k[12] & 252;
|
|
r[13] = k[13];
|
|
r[14] = k[14];
|
|
r[15] = k[15] & 15;
|
|
r[16] = 0;
|
|
|
|
for (j = 0;j < 17;++j) h[j] = 0;
|
|
|
|
while (inlen > 0) {
|
|
for (j = 0;j < 17;++j) c[j] = 0;
|
|
for (j = 0;(j < 16) && (j < inlen);++j) c[j] = in[j];
|
|
c[j] = 1;
|
|
in += j; inlen -= j;
|
|
add(h,c);
|
|
mulmod(h,r);
|
|
}
|
|
|
|
freeze(h);
|
|
|
|
for (j = 0;j < 16;++j) c[j] = k[j + 16];
|
|
c[16] = 0;
|
|
add(h,c);
|
|
for (j = 0;j < 16;++j) out[j] = h[j];
|
|
return 0;
|
|
}
|
|
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
//////////////////////////////////////////////////////////////////////////////
|
|
|
|
void Poly1305::compute(void *auth,const void *data,unsigned int len,const void *key)
|
|
throw()
|
|
{
|
|
crypto_onetimeauth((unsigned char *)auth,(const unsigned char *)data,len,(const unsigned char *)key);
|
|
}
|
|
|
|
} // namespace ZeroTier
|