diff options
Diffstat (limited to 'util.c')
| -rw-r--r-- | util.c | 26 |
1 files changed, 24 insertions, 2 deletions
@@ -5676,6 +5676,13 @@ Perl_get_hash_seed(pTHX_ unsigned char *seed_buffer) { while (isSPACE(*s)) s++; +#ifdef USE_PERL_PERTURB_KEYS + if (s[0] == '0' && s[1] == 0) { + PL_hash_rand_bits_enabled= 0; + } else { + PL_hash_rand_bits_enabled= 2; + } +#endif if (s[0] == '0' && s[1] == 'x') s += 2; @@ -5703,16 +5710,31 @@ Perl_get_hash_seed(pTHX_ unsigned char *seed_buffer) *ptr++ = (unsigned char)(Drand01() * (U8_MAX+1)); } } +#ifdef USE_PERL_PERTURB_KEYS { /* initialize PL_hash_rand_bits from the hash seed. * This value is highly volatile, it is updated every * hash insert, and is used as part of hash bucket chain * randomization and hash iterator randomization. */ unsigned long i; - PL_hash_rand_bits= 0; + PL_hash_rand_bits= 0xee49d17f; for( i = 0; i < sizeof(UV) ; i++ ) { - PL_hash_rand_bits = (PL_hash_rand_bits << 8) | seed_buffer[i % PERL_HASH_SEED_BYTES]; + PL_hash_rand_bits += seed_buffer[i % PERL_HASH_SEED_BYTES]; + PL_hash_rand_bits = ROTL_UV(PL_hash_rand_bits,8); } } + s= PerlEnv_getenv("PERL_PERTURB_KEYS"); + if (s) { + if (strEQ(s,"0") || strEQ(s,"NO")) { + PL_hash_rand_bits_enabled= 0; + } else if (strEQ(s,"1") || strEQ(s,"RANDOM")) { + PL_hash_rand_bits_enabled= 1; + } else if (strEQ(s,"2") || strEQ(s,"DETERMINISTIC")) { + PL_hash_rand_bits_enabled= 2; + } else { + Perl_warn(aTHX_ "perl: warning: strange setting in '$ENV{PERL_PERTURB_KEYS}': '%s'\n",s); + } + } +#endif } #ifdef PERL_GLOBAL_STRUCT |