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authorTom Gundersen <teg@jklm.no>2015-10-03 20:09:43 +0200
committerTom Gundersen <teg@jklm.no>2015-10-05 17:33:58 +0200
commit708684ef227eadafc0a2e8dff04879d6cc29d0f1 (patch)
tree7d8ffd699613a792ee34175dba7e4ad0441cedb0 /src/basic/siphash24.c
parenta245d90a898c2e1a77258aeb4b8a189ec771e804 (diff)
siphash24: introduce state struct
Encapsulate the four state variables in a struct so we can more easily pass them around.
Diffstat (limited to 'src/basic/siphash24.c')
-rw-r--r--src/basic/siphash24.c96
1 files changed, 54 insertions, 42 deletions
diff --git a/src/basic/siphash24.c b/src/basic/siphash24.c
index f68bd283a1..66e5a6105b 100644
--- a/src/basic/siphash24.c
+++ b/src/basic/siphash24.c
@@ -44,49 +44,61 @@ typedef uint8_t u8;
((u64)((p)[6]) << 48) | \
((u64)((p)[7]) << 56))
-#define SIPROUND \
+#define SIPROUND(state) \
do { \
- v0 += v1; v1=ROTL(v1,13); v1 ^= v0; v0=ROTL(v0,32); \
- v2 += v3; v3=ROTL(v3,16); v3 ^= v2; \
- v0 += v3; v3=ROTL(v3,21); v3 ^= v0; \
- v2 += v1; v1=ROTL(v1,17); v1 ^= v2; v2=ROTL(v2,32); \
+ (state)->v0 += (state)->v1; (state)->v1=ROTL((state)->v1,13); (state)->v1 ^= (state)->v0; (state)->v0=ROTL((state)->v0,32); \
+ (state)->v2 += (state)->v3; (state)->v3=ROTL((state)->v3,16); (state)->v3 ^= (state)->v2; \
+ (state)->v0 += (state)->v3; (state)->v3=ROTL((state)->v3,21); (state)->v3 ^= (state)->v0; \
+ (state)->v2 += (state)->v1; (state)->v1=ROTL((state)->v1,17); (state)->v1 ^= (state)->v2; (state)->v2=ROTL((state)->v2,32); \
} while(0)
+struct siphash {
+ u64 v0;
+ u64 v1;
+ u64 v2;
+ u64 v3;
+};
+
+static void siphash_init(struct siphash *state, const uint8_t k[16]) {
+ u64 k0, k1;
+
+ k0 = U8TO64_LE( k );
+ k1 = U8TO64_LE( k + 8 );
+
+ /* "somepseudorandomlygeneratedbytes" */
+ state->v0 = 0x736f6d6570736575ULL ^ k0;
+ state->v1 = 0x646f72616e646f6dULL ^ k1;
+ state->v2 = 0x6c7967656e657261ULL ^ k0;
+ state->v3 = 0x7465646279746573ULL ^ k1;
+}
+
/* SipHash-2-4 */
void siphash24(uint8_t out[8], const void *_in, size_t inlen, const uint8_t k[16])
{
- /* "somepseudorandomlygeneratedbytes" */
- u64 v0 = 0x736f6d6570736575ULL;
- u64 v1 = 0x646f72616e646f6dULL;
- u64 v2 = 0x6c7967656e657261ULL;
- u64 v3 = 0x7465646279746573ULL;
+ struct siphash state;
u64 b;
- u64 k0 = U8TO64_LE( k );
- u64 k1 = U8TO64_LE( k + 8 );
u64 m;
const u8 *in = _in;
const u8 *end = in + inlen - ( inlen % sizeof( u64 ) );
const int left = inlen & 7;
b = ( ( u64 )inlen ) << 56;
- v3 ^= k1;
- v2 ^= k0;
- v1 ^= k1;
- v0 ^= k0;
+
+ siphash_init(&state, k);
for ( ; in != end; in += 8 )
{
m = U8TO64_LE( in );
#ifdef DEBUG
- printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( v0 >> 32 ), ( u32 )v0 );
- printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( v1 >> 32 ), ( u32 )v1 );
- printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( v2 >> 32 ), ( u32 )v2 );
- printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( v3 >> 32 ), ( u32 )v3 );
+ 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 );
#endif
- v3 ^= m;
- SIPROUND;
- SIPROUND;
- v0 ^= m;
+ state.v3 ^= m;
+ SIPROUND(&state);
+ SIPROUND(&state);
+ state.v0 ^= m;
}
switch( left )
@@ -109,27 +121,27 @@ void siphash24(uint8_t out[8], const void *_in, size_t inlen, const uint8_t k[16
}
#ifdef DEBUG
- printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( v0 >> 32 ), ( u32 )v0 );
- printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( v1 >> 32 ), ( u32 )v1 );
- printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( v2 >> 32 ), ( u32 )v2 );
- printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( v3 >> 32 ), ( u32 )v3 );
+ 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 );
#endif
- v3 ^= b;
- SIPROUND;
- SIPROUND;
- v0 ^= b;
+ state.v3 ^= b;
+ SIPROUND(&state);
+ SIPROUND(&state);
+ state.v0 ^= b;
#ifdef DEBUG
- printf( "(%3d) v0 %08x %08x\n", ( int )inlen, ( u32 )( v0 >> 32 ), ( u32 )v0 );
- printf( "(%3d) v1 %08x %08x\n", ( int )inlen, ( u32 )( v1 >> 32 ), ( u32 )v1 );
- printf( "(%3d) v2 %08x %08x\n", ( int )inlen, ( u32 )( v2 >> 32 ), ( u32 )v2 );
- printf( "(%3d) v3 %08x %08x\n", ( int )inlen, ( u32 )( v3 >> 32 ), ( u32 )v3 );
+ 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
- v2 ^= 0xff;
- SIPROUND;
- SIPROUND;
- SIPROUND;
- SIPROUND;
- b = v0 ^ v1 ^ v2 ^ v3;
+ state.v2 ^= 0xff;
+ SIPROUND(&state);
+ SIPROUND(&state);
+ SIPROUND(&state);
+ SIPROUND(&state);
+ b = state.v0 ^ state.v1 ^ state.v2 ^ state.v3;
U64TO8_LE( out, b );
}