diff options
Diffstat (limited to 'lib/random32.c')
| -rw-r--r-- | lib/random32.c | 195 |
1 files changed, 189 insertions, 6 deletions
diff --git a/lib/random32.c b/lib/random32.c index 27adb753180f..82da4f4c3489 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -38,6 +38,11 @@ #include <linux/export.h> #include <linux/jiffies.h> #include <linux/random.h> +#include <linux/sched.h> + +#ifdef CONFIG_RANDOM32_SELFTEST +static void __init prandom_state_selftest(void); +#endif static DEFINE_PER_CPU(struct rnd_state, net_rand_state); @@ -142,6 +147,23 @@ static void prandom_warmup(struct rnd_state *state) prandom_u32_state(state); } +static void prandom_seed_very_weak(struct rnd_state *state, u32 seed) +{ + /* Note: This sort of seeding is ONLY used in test cases and + * during boot at the time from core_initcall until late_initcall + * as we don't have a stronger entropy source available yet. + * After late_initcall, we reseed entire state, we have to (!), + * otherwise an attacker just needs to search 32 bit space to + * probe for our internal 128 bit state if he knows a couple + * of prandom32 outputs! + */ +#define LCG(x) ((x) * 69069U) /* super-duper LCG */ + state->s1 = __seed(LCG(seed), 2U); + state->s2 = __seed(LCG(state->s1), 8U); + state->s3 = __seed(LCG(state->s2), 16U); + state->s4 = __seed(LCG(state->s3), 128U); +} + /** * prandom_seed - add entropy to pseudo random number generator * @seed: seed value @@ -172,15 +194,14 @@ static int __init prandom_init(void) { int i; +#ifdef CONFIG_RANDOM32_SELFTEST + prandom_state_selftest(); +#endif + for_each_possible_cpu(i) { struct rnd_state *state = &per_cpu(net_rand_state,i); -#define LCG(x) ((x) * 69069U) /* super-duper LCG */ - state->s1 = __seed(LCG((i + jiffies) ^ random_get_entropy()), 2U); - state->s2 = __seed(LCG(state->s1), 8U); - state->s3 = __seed(LCG(state->s2), 16U); - state->s4 = __seed(LCG(state->s3), 128U); - + prandom_seed_very_weak(state, (i + jiffies) ^ random_get_entropy()); prandom_warmup(state); } return 0; @@ -253,3 +274,165 @@ static int __init prandom_reseed(void) return 0; } late_initcall(prandom_reseed); + +#ifdef CONFIG_RANDOM32_SELFTEST +static struct prandom_test1 { + u32 seed; + u32 result; +} test1[] = { + { 1U, 3484351685U }, + { 2U, 2623130059U }, + { 3U, 3125133893U }, + { 4U, 984847254U }, +}; + +static struct prandom_test2 { + u32 seed; + u32 iteration; + u32 result; +} test2[] = { + /* Test cases against taus113 from GSL library. */ + { 931557656U, 959U, 2975593782U }, + { 1339693295U, 876U, 3887776532U }, + { 1545556285U, 961U, 1615538833U }, + { 601730776U, 723U, 1776162651U }, + { 1027516047U, 687U, 511983079U }, + { 416526298U, 700U, 916156552U }, + { 1395522032U, 652U, 2222063676U }, + { 366221443U, 617U, 2992857763U }, + { 1539836965U, 714U, 3783265725U }, + { 556206671U, 994U, 799626459U }, + { 684907218U, 799U, 367789491U }, + { 2121230701U, 931U, 2115467001U }, + { 1668516451U, 644U, 3620590685U }, + { 768046066U, 883U, 2034077390U }, + { 1989159136U, 833U, 1195767305U }, + { 536585145U, 996U, 3577259204U }, + { 1008129373U, 642U, 1478080776U }, + { 1740775604U, 939U, 1264980372U }, + { 1967883163U, 508U, 10734624U }, + { 1923019697U, 730U, 3821419629U }, + { 442079932U, 560U, 3440032343U }, + { 1961302714U, 845U, 841962572U }, + { 2030205964U, 962U, 1325144227U }, + { 1160407529U, 507U, 240940858U }, + { 635482502U, 779U, 4200489746U }, + { 1252788931U, 699U, 867195434U }, + { 1961817131U, 719U, 668237657U }, + { 1071468216U, 983U, 917876630U }, + { 1281848367U, 932U, 1003100039U }, + { 582537119U, 780U, 1127273778U }, + { 1973672777U, 853U, 1071368872U }, + { 1896756996U, 762U, 1127851055U }, + { 847917054U, 500U, 1717499075U }, + { 1240520510U, 951U, 2849576657U }, + { 1685071682U, 567U, 1961810396U }, + { 1516232129U, 557U, 3173877U }, + { 1208118903U, 612U, 1613145022U }, + { 1817269927U, 693U, 4279122573U }, + { 1510091701U, 717U, 638191229U }, + { 365916850U, 807U, 600424314U }, + { 399324359U, 702U, 1803598116U }, + { 1318480274U, 779U, 2074237022U }, + { 697758115U, 840U, 1483639402U }, + { 1696507773U, 840U, 577415447U }, + { 2081979121U, 981U, 3041486449U }, + { 955646687U, 742U, 3846494357U }, + { 1250683506U, 749U, 836419859U }, + { 595003102U, 534U, 366794109U }, + { 47485338U, 558U, 3521120834U }, + { 619433479U, 610U, 3991783875U }, + { 704096520U, 518U, 4139493852U }, + { 1712224984U, 606U, 2393312003U }, + { 1318233152U, 922U, 3880361134U }, + { 855572992U, 761U, 1472974787U }, + { 64721421U, 703U, 683860550U }, + { 678931758U, 840U, 380616043U }, + { 692711973U, 778U, 1382361947U }, + { 677703619U, 530U, 2826914161U }, + { 92393223U, 586U, 1522128471U }, + { 1222592920U, 743U, 3466726667U }, + { 358288986U, 695U, 1091956998U }, + { 1935056945U, 958U, 514864477U }, + { 735675993U, 990U, 1294239989U }, + { 1560089402U, 897U, 2238551287U }, + { 70616361U, 829U, 22483098U }, + { 368234700U, 731U, 2913875084U }, + { 20221190U, 879U, 1564152970U }, + { 539444654U, 682U, 1835141259U }, + { 1314987297U, 840U, 1801114136U }, + { 2019295544U, 645U, 3286438930U }, + { 469023838U, 716U, 1637918202U }, + { 1843754496U, 653U, 2562092152U }, + { 400672036U, 809U, 4264212785U }, + { 404722249U, 965U, 2704116999U }, + { 600702209U, 758U, 584979986U }, + { 519953954U, 667U, 2574436237U }, + { 1658071126U, 694U, 2214569490U }, + { 420480037U, 749U, 3430010866U }, + { 690103647U, 969U, 3700758083U }, + { 1029424799U, 937U, 3787746841U }, + { 2012608669U, 506U, 3362628973U }, + { 1535432887U, 998U, 42610943U }, + { 1330635533U, 857U, 3040806504U }, + { 1223800550U, 539U, 3954229517U }, + { 1322411537U, 680U, 3223250324U }, + { 1877847898U, 945U, 2915147143U }, + { 1646356099U, 874U, 965988280U }, + { 805687536U, 744U, 4032277920U }, + { 1948093210U, 633U, 1346597684U }, + { 392609744U, 783U, 1636083295U }, + { 690241304U, 770U, 1201031298U }, + { 1360302965U, 696U, 1665394461U }, + { 1220090946U, 780U, 1316922812U }, + { 447092251U, 500U, 3438743375U }, + { 1613868791U, 592U, 828546883U }, + { 523430951U, 548U, 2552392304U }, + { 726692899U, 810U, 1656872867U }, + { 1364340021U, 836U, 3710513486U }, + { 1986257729U, 931U, 935013962U }, + { 407983964U, 921U, 728767059U }, +}; + +static void __init prandom_state_selftest(void) +{ + int i, j, errors = 0, runs = 0; + bool error = false; + + for (i = 0; i < ARRAY_SIZE(test1); i++) { + struct rnd_state state; + + prandom_seed_very_weak(&state, test1[i].seed); + prandom_warmup(&state); + + if (test1[i].result != prandom_u32_state(&state)) + error = true; + } + + if (error) + pr_warn("prandom: seed boundary self test failed\n"); + else + pr_info("prandom: seed boundary self test passed\n"); + + for (i = 0; i < ARRAY_SIZE(test2); i++) { + struct rnd_state state; + + prandom_seed_very_weak(&state, test2[i].seed); + prandom_warmup(&state); + + for (j = 0; j < test2[i].iteration - 1; j++) + prandom_u32_state(&state); + + if (test2[i].result != prandom_u32_state(&state)) + errors++; + + runs++; + cond_resched(); + } + + if (errors) + pr_warn("prandom: %d/%d self tests failed\n", errors, runs); + else + pr_info("prandom: %d self tests passed\n", runs); +} +#endif |