diff options
| -rw-r--r-- | ChangeLog | 14 | ||||
| -rw-r--r-- | random.c | 62 | ||||
| -rw-r--r-- | test/ruby/test_rand.rb | 9 |
3 files changed, 56 insertions, 29 deletions
@@ -1,3 +1,17 @@ +Thu Oct 22 06:20:48 2015 KOSAKI Motohiro <kosaki.motohiro@gmail.com> + + * random.c (Init_RandomSeed): move all Random::DEFAULT + construction bits to Init_RandomSeed2. Random::DEFAULT + and Ruby internal hashes are no longer shared their seed. + * random.c (Init_RandomSeed2): ditto. And, kill evil + rb_obj_reveal() stuff. + + * random.c (init_hashseed): add MT argument. + * random.c: (init_siphash): ditto. + + * test/ruby/test_rand.rb (TestRand#test_default_seed): new + test for Random::DEFAULT::seed. + Thu Oct 22 05:23:48 2015 KOSAKI Motohiro <kosaki.motohiro@gmail.com> * random.c (init_hashseed, init_siphash): extract initialize @@ -1452,24 +1452,9 @@ static union { uint32_t u32[(16 * sizeof(uint8_t) - 1) / sizeof(uint32_t)]; } sipseed; -static VALUE -init_randomseed(struct MT *mt) -{ - uint32_t initial[DEFAULT_SEED_CNT]; - VALUE seed; - - fill_random_seed(initial); - init_by_array(mt, initial, DEFAULT_SEED_CNT); - seed = make_seed_value(initial); - explicit_bzero(initial, DEFAULT_SEED_LEN); - return seed; -} - static void -init_hashseed(void) +init_hashseed(struct MT *mt) { - struct MT *mt = default_mt(); - hashseed = genrand_int32(mt); #if SIZEOF_ST_INDEX_T*CHAR_BIT > 4*8 hashseed <<= 32; @@ -1486,9 +1471,8 @@ init_hashseed(void) } static void -init_siphash(void) +init_siphash(struct MT *mt) { - struct MT *mt = default_mt(); int i; for (i = 0; i < numberof(sipseed.u32); ++i) @@ -1512,28 +1496,48 @@ rb_memhash(const void *ptr, long len) #endif } +/* Initialize Ruby internal seeds */ void Init_RandomSeed(void) { - rb_random_t *r = &default_rand; - struct MT *mt = &r->mt; - VALUE seed = init_randomseed(mt); + /* + Don't reuse this MT for Random::DEFAULT. Random::DEFAULT::seed shouldn't + provide a hint that an attacker guess siphash's seed. + */ + struct MT mt; + uint32_t initial_seed[DEFAULT_SEED_CNT]; - init_hashseed(); - init_siphash(); + fill_random_seed(initial_seed); + init_by_array(&mt, initial_seed, DEFAULT_SEED_CNT); - rb_global_variable(&r->seed); - r->seed = seed; + init_hashseed(&mt); + init_siphash(&mt); + + explicit_bzero(initial_seed, DEFAULT_SEED_LEN); +} + +static VALUE +init_randomseed(struct MT *mt) +{ + uint32_t initial[DEFAULT_SEED_CNT]; + VALUE seed; + + fill_random_seed(initial); + init_by_array(mt, initial, DEFAULT_SEED_CNT); + seed = make_seed_value(initial); + explicit_bzero(initial, DEFAULT_SEED_LEN); + return seed; } +/* construct Random::DEFAULT bits */ static void Init_RandomSeed2(void) { - VALUE seed = default_rand.seed; + rb_random_t *r = &default_rand; + struct MT *mt = &r->mt; - if (RB_TYPE_P(seed, T_BIGNUM)) { - rb_obj_reveal(seed, rb_cBignum); - } + r->seed = init_randomseed(mt); + rb_global_variable(&r->seed); } void diff --git a/test/ruby/test_rand.rb b/test/ruby/test_rand.rb index d2a1244b0b..db2d4578b8 100644 --- a/test/ruby/test_rand.rb +++ b/test/ruby/test_rand.rb @@ -524,4 +524,13 @@ END [1, 2].sample(1, random: gen) assert_equal(2, gen.limit, bug7935) end + + def test_default_seed + assert_separately([], <<-End) + seed = Random::DEFAULT::seed + rand1 = Random::DEFAULT::rand + rand2 = Random.new(seed).rand + assert_equal(rand1, rand2) + End + end end |