Commit 4a740451 authored by Nick Mathewson's avatar Nick Mathewson 🦞
Browse files

Merge remote-tracking branch 'public/bug11750'

parents 5cea500c e9c1c3ff

changes/bug11750

0 → 100644
+5 −0
Original line number Diff line number Diff line 
  o Minor features (security):

    - Apply the secure SipHash-2-4 function to the hash table mapping

      circuit IDs and channels to circuits. We missed this one when we

      were converting all the other hash functions to use SipHash back

      in 0.2.5.3-alpha. Resolves ticket 11750.

src/or/circuitlist.c

+9 −1
Original line number Diff line number Diff line
@@ -76,7 +76,15 @@ chan_circid_entries_eq_(chan_circid_circuit_map_t *a, 
static INLINE unsigned int

chan_circid_entry_hash_(chan_circid_circuit_map_t *a)

{

  return ((unsigned)a->circ_id) ^ (unsigned)(uintptr_t)(a->chan);

  /* Try to squeze the siphash input into 8 bytes to save any extra siphash

   * rounds.  This hash function is in the critical path. */

  uintptr_t chan = (uintptr_t) (void*) a->chan;

  uint32_t array[2];

  array[0] = a->circ_id;

  /* The low bits of the channel pointer are uninteresting, since the channel

   * is a pretty big structure. */

  array[1] = (uint32_t) (chan >> 6);

  return (unsigned) siphash24g(array, sizeof(array));

}



/** Map from [chan,circid] to circuit. */

src/test/bench.c

+25 −0
Original line number Diff line number Diff line
@@ -337,6 +337,30 @@ bench_dmap(void) 
  smartlist_free(sl2);

}



static void

bench_siphash(void)

{

  char buf[128];

  int lens[] = { 7, 8, 15, 16, 20, 32, 111, 128, -1 };

  int i, j;

  uint64_t total;

  uint64_t start, end;

  const int N = 300000;

  crypto_rand(buf, sizeof(buf));



  for (i = 0; lens[i] > 0; ++i) {

    total = 0;

    reset_perftime();

    start = perftime();

    for (j = 0; j < N; ++j) {

      total += siphash24g(buf, lens[i]);

    }

    end = perftime();

    printf("siphash24g(%d): %.2f ns per call\n",

           lens[i], NANOCOUNT(start,end,N));

  }

}



static void

bench_cell_ops(void)

{
@@ -487,6 +511,7 @@ typedef struct benchmark_t { 


static struct benchmark_t benchmarks[] = {

  ENT(dmap),

  ENT(siphash),

  ENT(aes),

  ENT(onion_TAP),

#ifdef CURVE25519_ENABLED