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siphash24: move last compression iteration from compression step to finalization step

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The last compression is special as it deals with the length byte, and padding. Move
it to the finalization step in preparation for making compression decomposable.
This commit is contained in:
Tom Gundersen 2015-10-03 21:27:25 +02:00
parent c7b68d84e4
commit f2936011c5
1 changed files with 33 additions and 27 deletions
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60
src/basic/siphash24.c
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@ -57,6 +57,8 @@ struct siphash {
u64 v1;
u64 v2;
u64 v3;
u64 padding;
size_t inlen;
};
static void siphash_init(struct siphash *state, const uint8_t k[16]) {
@ -70,26 +72,27 @@ static void siphash_init(struct siphash *state, const uint8_t k[16]) {
state->v1 = 0x646f72616e646f6dULL ^ k1;
state->v2 = 0x6c7967656e657261ULL ^ k0;
state->v3 = 0x7465646279746573ULL ^ k1;
state->padding = 0;
state->inlen = 0;
}
static void siphash24_compress(const void *_in, size_t inlen, struct siphash *state) {
u64 b;
u64 m;
const u8 *in = _in;
const u8 *end = in + inlen - ( inlen % sizeof( u64 ) );
const int left = inlen & 7;
b = ( ( u64 )inlen ) << 56;
state->inlen = inlen;
for ( ; in != end; in += 8 )
{
m = U8TO64_LE( in );
#ifdef DEBUG
printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
printf( "(%3d) compress %08x %08x\n", ( int )inlen, ( u32 )( m >> 32 ), ( u32 )m );
printf( "(%3d) v0 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
printf( "(%3d) compress %08x %08x\n", ( int )state->inlen, ( u32 )( m >> 32 ), ( u32 )m );
#endif
state->v3 ^= m;
SIPROUND(state);
@ -99,43 +102,46 @@ static void siphash24_compress(const void *_in, size_t inlen, struct siphash *st
switch( left )
{
case 7: b |= ( ( u64 )in[ 6] ) << 48;
case 7: state->padding |= ( ( u64 )in[ 6] ) << 48;
case 6: b |= ( ( u64 )in[ 5] ) << 40;
case 6: state->padding |= ( ( u64 )in[ 5] ) << 40;
case 5: b |= ( ( u64 )in[ 4] ) << 32;
case 5: state->padding |= ( ( u64 )in[ 4] ) << 32;
case 4: b |= ( ( u64 )in[ 3] ) << 24;
case 4: state->padding |= ( ( u64 )in[ 3] ) << 24;
case 3: b |= ( ( u64 )in[ 2] ) << 16;
case 3: state->padding |= ( ( u64 )in[ 2] ) << 16;
case 2: b |= ( ( u64 )in[ 1] ) << 8;
case 2: state->padding |= ( ( u64 )in[ 1] ) << 8;
case 1: b |= ( ( u64 )in[ 0] ); break;
case 1: state->padding |= ( ( u64 )in[ 0] ); break;
case 0: break;
}
}
static u64 siphash24_finalize(struct siphash *state) {
u64 b;
b = state->padding | (( ( u64 )state->inlen ) << 56);
#ifdef DEBUG
printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
printf( "(%3d) padding %08x %08x\n", ( int )inlen, ( u32 )( b >> 32 ), ( u32 )b );
printf( "(%3d) v0 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
printf( "(%3d) padding %08x %08x\n", ( int )state->inlen, ( u32 )( state->padding >> 32 ), ( u32 )state->padding );
#endif
state->v3 ^= b;
SIPROUND(state);
SIPROUND(state);
state->v0 ^= b;
#ifdef DEBUG
printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
#endif
}
static u64 siphash24_finalize(struct siphash *state) {
#ifdef DEBUG
printf( "(%3d) v0 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v0 >> 32 ), ( u32 )state->v0 );
printf( "(%3d) v1 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v1 >> 32 ), ( u32 )state->v1 );
printf( "(%3d) v2 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v2 >> 32 ), ( u32 )state->v2 );
printf( "(%3d) v3 %08x %08x\n", ( int )state->inlen, ( u32 )( state->v3 >> 32 ), ( u32 )state->v3 );
#endif
state->v2 ^= 0xff;
SIPROUND(state);
SIPROUND(state);