/* version 20080913 D. J. Bernstein Public domain. */ #include "crypto_core_salsa2012.h" #include "crypto_stream.h" typedef unsigned int uint32; static const unsigned char sigma[16] = "expand 32-byte k"; int crypto_stream_xor( unsigned char *c, const unsigned char *m,unsigned long long mlen, const unsigned char *n, const unsigned char *k ) { unsigned char in[16]; unsigned char block[64]; int i; unsigned int u; if (!mlen) return 0; for (i = 0;i < 8;++i) in[i] = n[i]; for (i = 8;i < 16;++i) in[i] = 0; while (mlen >= 64) { crypto_core_salsa2012(block,in,k,sigma); for (i = 0;i < 64;++i) c[i] = m[i] ^ block[i]; u = 1; for (i = 8;i < 16;++i) { u += (unsigned int) in[i]; in[i] = u; u >>= 8; } mlen -= 64; c += 64; m += 64; } if (mlen) { crypto_core_salsa2012(block,in,k,sigma); for (i = 0;i < mlen;++i) c[i] = m[i] ^ block[i]; } return 0; }