Uh-oh! Random number generator is not pseudorandom™

$rand  = $this->psl['crypt/rand'];
for ($i=0; $i<10000; $i++) {
  $num = floor($rand->int(0, 1000000) / 1000);
  if (isset($used[$num])) {
    $used[$num]++;
  }
  else {
    $used[$num] = 1;
  }
}
ksort($used);
print_r($used);

Here is the output. As you can see it is pretty much a standard normal distribution curve right in the middle of the range:

Array
(
    [479] => 1
    [480] => 2
    [481] => 1
    [482] => 1
    [483] => 4
    [484] => 11
    [485] => 26
    [486] => 26
    [487] => 63
    [488] => 89
    [489] => 162
    [490] => 225
    [491] => 345
    [492] => 401
    [493] => 509
    [494] => 617
    [495] => 770
    [496] => 792
    [497] => 853
    [498] => 896
    [499] => 830
    [500] => 738
    [501] => 675
    [502] => 489
    [503] => 411
    [504] => 333
    [505] => 253
    [506] => 212
    [507] => 91
    [508] => 73
    [509] => 51
    [510] => 25
    [511] => 12
    [512] => 5
    [513] => 6
    [514] => 1
    [518] => 1
)

Why not just use mt_rand()?

By the way, the current RNG is ridiculously slow for large ranges while mt_rand() is almost instant.

Oh, and here's the output for the same code using mt_rand():

Array
(
    [0] => 9
    [1] => 8
    [2] => 15
    [3] => 10
    [4] => 7
    [5] => 9
    [6] => 6
    [7] => 7
    [8] => 8
    [9] => 11
    [10] => 15
    [11] => 8
    [12] => 9
    [13] => 13
    [14] => 10
    [15] => 8
    [16] => 13
    [17] => 10
    [18] => 12
    [19] => 10
    [20] => 10
    [21] => 6
    [22] => 9
    [23] => 13
    [24] => 15
    [25] => 8
    [26] => 14
    [27] => 8
    [28] => 7
    [29] => 10
    [30] => 7
    [31] => 10
    [32] => 8
    [33] => 12
    [34] => 9
    [35] => 4
    [36] => 6
    [37] => 8
    [38] => 6
    [39] => 11
    [40] => 4
    [41] => 13
    [42] => 11
    [43] => 5
    [44] => 8
    [45] => 10
    [46] => 15
    [47] => 10
    [48] => 9
    [49] => 10
    [50] => 10
    [51] => 10
    [52] => 11
    [53] => 10
    [54] => 11
    [55] => 10
    [56] => 11
    [57] => 16
    [58] => 8
    [59] => 9
    [60] => 8
    [61] => 11
    [62] => 12
    [63] => 9
    [64] => 7
    [65] => 11
    [66] => 10
    [67] => 9
    [68] => 12
    [69] => 8
    [70] => 12
    [71] => 13
    [72] => 13
    [73] => 12
    [74] => 7
    [75] => 13
    [76] => 8
    [77] => 7
    [78] => 8
    [79] => 10
    [80] => 8
    [81] => 12
    [82] => 11
    [83] => 8
    [84] => 10
    [85] => 8
    [86] => 10
    [87] => 12
    [88] => 7
    [89] => 18
    [90] => 12
    [91] => 4
    [92] => 10
    [93] => 4
    [94] => 9
    [95] => 7
    [96] => 12
    [97] => 7
    [98] => 11
    [99] => 10
    [100] => 2
    [101] => 7
    [102] => 16
    [103] => 12
    [104] => 11
    [105] => 9
    [106] => 6
    [107] => 12
    [108] => 16
    [109] => 7
    [110] => 10
    [111] => 9
    [112] => 10
    [113] => 10
    [114] => 14
    [115] => 10
    [116] => 13
    [117] => 8
    [118] => 10
    [119] => 10
    [120] => 10
    [121] => 10
    [122] => 13
    [123] => 8
    [124] => 7
    [125] => 3
    [126] => 11
    [127] => 7
    [128] => 10
    [129] => 14
    [130] => 10
    [131] => 13
    [132] => 10
    [133] => 8
    [134] => 6
    [135] => 8
    [136] => 15
    [137] => 8
    [138] => 6
    [139] => 14
    [140] => 12
    [141] => 8
    [142] => 8
    [143] => 14
    [144] => 12
    [145] => 9
    [146] => 8
    [147] => 8
    [148] => 9
    [149] => 11
    [150] => 8
    [151] => 10
    [152] => 10
    [153] => 13
    [154] => 8
    [155] => 13
    [156] => 14
    [157] => 11
    [158] => 10
    [159] => 6
    [160] => 9
    [161] => 15
    [162] => 9
    [163] => 9
    [164] => 10
    [165] => 12
    [166] => 12
    [167] => 7
    [168] => 12
    [169] => 13
    [170] => 10
    [171] => 8
    [172] => 13
    [173] => 12
    [174] => 7
    [175] => 10
    [176] => 18
    [177] => 14
    [178] => 13
    [179] => 13
    [180] => 9
    [181] => 8
    [182] => 8
    [183] => 11
    [184] => 5
    [185] => 12
    [186] => 13
    [187] => 15
    [188] => 10
    [189] => 12
    [190] => 8
    [191] => 9
    [192] => 10
    [193] => 7
    [194] => 9
    [195] => 8
    [196] => 13
    [197] => 10
    [198] => 12
    [199] => 8
    [200] => 5
    [201] => 12
    [202] => 13
    [203] => 13
    [204] => 7
    [205] => 6
    [206] => 7
    [207] => 7
    [208] => 9
    [209] => 11
    [210] => 8
    [211] => 14
    [212] => 11
    [213] => 11
    [214] => 6
    [215] => 10
    [216] => 9
    [217] => 12
    [218] => 13
    [219] => 7
    [220] => 10
    [221] => 10
    [222] => 5
    [223] => 6
    [224] => 6
    [225] => 7
    [226] => 3
    [227] => 8
    [228] => 5
    [229] => 8
    [230] => 9
    [231] => 9
    [232] => 16
    [233] => 11
    [234] => 8
    [235] => 12
    [236] => 11
    [237] => 7
    [238] => 11
    [239] => 15
    [240] => 8
    [241] => 8
    [242] => 3
    [243] => 9
    [244] => 9
    [245] => 5
    [246] => 8
    [247] => 4
    [248] => 11
    [249] => 10
    [250] => 8
    [251] => 12
    [252] => 8
    [253] => 15
    [254] => 7
    [255] => 12
    [256] => 16
    [257] => 7
    [258] => 10
    [259] => 10
    [260] => 7
    [261] => 13
    [262] => 11
    [263] => 13
    [264] => 11
    [265] => 8
    [266] => 8
    [267] => 9
    [268] => 13
    [269] => 12
    [270] => 13
    [271] => 9
    [272] => 19
    [273] => 15
    [274] => 12
    [275] => 7
    [276] => 8
    [277] => 18
    [278] => 10
    [279] => 5
    [280] => 7
    [281] => 11
    [282] => 13
    [283] => 6
    [284] => 7
    [285] => 8
    [286] => 10
    [287] => 7
    [288] => 10
    [289] => 3
    [290] => 11
    [291] => 8
    [292] => 15
    [293] => 10
    [294] => 8
    [295] => 9
    [296] => 11
    [297] => 12
    [298] => 10
    [299] => 5
    [300] => 12
    [301] => 12
    [302] => 12
    [303] => 11
    [304] => 11
    [305] => 13
    [306] => 11
    [307] => 7
    [308] => 5
    [309] => 13
    [310] => 8
    [311] => 10
    [312] => 9
    [313] => 7
    [314] => 9
    [315] => 16
    [316] => 15
    [317] => 10
    [318] => 5
    [319] => 11
    [320] => 12
    [321] => 8
    [322] => 7
    [323] => 6
    [324] => 13
    [325] => 9
    [326] => 12
    [327] => 14
    [328] => 12
    [329] => 14
    [330] => 12
    [331] => 7
    [332] => 11
    [333] => 9
    [334] => 5
    [335] => 11
    [336] => 9
    [337] => 3
    [338] => 16
    [339] => 10
    [340] => 9
    [341] => 14
    [342] => 6
    [343] => 8
    [344] => 9
    [345] => 14
    [346] => 8
    [347] => 7
    [348] => 11
    [349] => 7
    [350] => 9
    [351] => 14
    [352] => 13
    [353] => 8
    [354] => 10
    [355] => 10
    [356] => 11
    [357] => 15
    [358] => 10
    [359] => 12
    [360] => 6
    [361] => 4
    [362] => 7
    [363] => 8
    [364] => 7
    [365] => 12
    [366] => 13
    [367] => 13
    [368] => 12
    [369] => 7
    [370] => 12
    [371] => 8
    [372] => 9
    [373] => 10
    [374] => 10
    [375] => 17
    [376] => 9
    [377] => 6
    [378] => 6
    [379] => 8
    [380] => 8
    [381] => 7
    [382] => 13
    [383] => 13
    [384] => 8
    [385] => 11
    [386] => 8
    [387] => 18
    [388] => 13
    [389] => 8
    [390] => 7
    [391] => 8
    [392] => 5
    [393] => 5
    [394] => 10
    [395] => 17
    [396] => 4
    [397] => 12
    [398] => 11
    [399] => 11
    [400] => 7
    [401] => 10
    [402] => 13
    [403] => 7
    [404] => 15
    [405] => 17
    [406] => 13
    [407] => 7
    [408] => 14
    [409] => 8
    [410] => 6
    [411] => 6
    [412] => 12
    [413] => 6
    [414] => 9
    [415] => 6
    [416] => 16
    [417] => 12
    [418] => 5
    [419] => 10
    [420] => 7
    [421] => 12
    [422] => 8
    [423] => 11
    [424] => 8
    [425] => 11
    [426] => 6
    [427] => 11
    [428] => 8
    [429] => 8
    [430] => 8
    [431] => 12
    [432] => 7
    [433] => 10
    [434] => 6
    [435] => 12
    [436] => 13
    [437] => 9
    [438] => 9
    [439] => 11
    [440] => 8
    [441] => 5
    [442] => 13
    [443] => 5
    [444] => 10
    [445] => 9
    [446] => 12
    [447] => 10
    [448] => 5
    [449] => 8
    [450] => 8
    [451] => 14
    [452] => 8
    [453] => 6
    [454] => 10
    [455] => 10
    [456] => 17
    [457] => 7
    [458] => 10
    [459] => 11
    [460] => 6
    [461] => 8
    [462] => 6
    [463] => 8
    [464] => 10
    [465] => 8
    [466] => 9
    [467] => 8
    [468] => 8
    [469] => 7
    [470] => 10
    [471] => 9
    [472] => 11
    [473] => 9
    [474] => 10
    [475] => 11
    [476] => 14
    [477] => 11
    [478] => 11
    [479] => 15
    [480] => 6
    [481] => 9
    [482] => 7
    [483] => 21
    [484] => 7
    [485] => 11
    [486] => 8
    [487] => 11
    [488] => 10
    [489] => 17
    [490] => 7
    [491] => 15
    [492] => 12
    [493] => 15
    [494] => 9
    [495] => 9
    [496] => 8
    [497] => 13
    [498] => 13
    [499] => 10
    [500] => 9
    [501] => 14
    [502] => 8
    [503] => 8
    [504] => 14
    [505] => 18
    [506] => 8
    [507] => 10
    [508] => 8
    [509] => 11
    [510] => 9
    [511] => 11
    [512] => 4
    [513] => 15
    [514] => 11
    [515] => 8
    [516] => 6
    [517] => 6
    [518] => 10
    [519] => 10
    [520] => 11
    [521] => 11
    [522] => 8
    [523] => 15
    [524] => 9
    [525] => 12
    [526] => 7
    [527] => 12
    [528] => 10
    [529] => 9
    [530] => 10
    [531] => 11
    [532] => 9
    [533] => 7
    [534] => 14
    [535] => 9
    [536] => 9
    [537] => 9
    [538] => 7
    [539] => 12
    [540] => 14
    [541] => 18
    [542] => 13
    [543] => 6
    [544] => 12
    [545] => 5
    [546] => 14
    [547] => 15
    [548] => 7
    [549] => 8
    [550] => 11
    [551] => 7
    [552] => 11
    [553] => 14
    [554] => 11
    [555] => 15
    [556] => 7
    [557] => 9
    [558] => 9
    [559] => 6
    [560] => 9
    [561] => 11
    [562] => 14
    [563] => 7
    [564] => 12
    [565] => 11
    [566] => 10
    [567] => 6
    [568] => 9
    [569] => 8
    [570] => 11
    [571] => 11
    [572] => 18
    [573] => 9
    [574] => 10
    [575] => 7
    [576] => 11
    [577] => 11
    [578] => 13
    [579] => 9
    [580] => 6
    [581] => 10
    [582] => 7
    [583] => 9
    [584] => 10
    [585] => 6
    [586] => 10
    [587] => 8
    [588] => 18
    [589] => 14
    [590] => 8
    [591] => 9
    [592] => 13
    [593] => 16
    [594] => 7
    [595] => 8
    [596] => 10
    [597] => 12
    [598] => 12
    [599] => 13
    [600] => 9
    [601] => 7
    [602] => 11
    [603] => 9
    [604] => 10
    [605] => 11
    [606] => 15
    [607] => 12
    [608] => 9
    [609] => 13
    [610] => 9
    [611] => 6
    [612] => 9
    [613] => 11
    [614] => 11
    [615] => 5
    [616] => 15
    [617] => 11
    [618] => 9
    [619] => 9
    [620] => 12
    [621] => 13
    [622] => 9
    [623] => 9
    [624] => 9
    [625] => 10
    [626] => 6
    [627] => 8
    [628] => 12
    [629] => 12
    [630] => 11
    [631] => 9
    [632] => 10
    [633] => 12
    [634] => 13
    [635] => 15
    [636] => 4
    [637] => 15
    [638] => 8
    [639] => 9
    [640] => 10
    [641] => 9
    [642] => 14
    [643] => 12
    [644] => 13
    [645] => 12
    [646] => 5
    [647] => 9
    [648] => 9
    [649] => 7
    [650] => 7
    [651] => 16
    [652] => 12
    [653] => 17
    [654] => 6
    [655] => 6
    [656] => 14
    [657] => 9
    [658] => 8
    [659] => 7
    [660] => 12
    [661] => 12
    [662] => 11
    [663] => 4
    [664] => 11
    [665] => 15
    [666] => 20
    [667] => 10
    [668] => 14
    [669] => 10
    [670] => 7
    [671] => 10
    [672] => 6
    [673] => 12
    [674] => 10
    [675] => 11
    [676] => 6
    [677] => 10
    [678] => 7
    [679] => 8
    [680] => 13
    [681] => 13
    [682] => 11
    [683] => 16
    [684] => 14
    [685] => 11
    [686] => 16
    [687] => 13
    [688] => 4
    [689] => 9
    [690] => 11
    [691] => 14
    [692] => 14
    [693] => 8
    [694] => 9
    [695] => 13
    [696] => 9
    [697] => 2
    [698] => 14
    [699] => 16
    [700] => 11
    [701] => 7
    [702] => 10
    [703] => 11
    [704] => 10
    [705] => 13
    [706] => 10
    [707] => 10
    [708] => 13
    [709] => 7
    [710] => 17
    [711] => 7
    [712] => 9
    [713] => 10
    [714] => 10
    [715] => 12
    [716] => 12
    [717] => 10
    [718] => 15
    [719] => 9
    [720] => 7
    [721] => 11
    [722] => 8
    [723] => 7
    [724] => 8
    [725] => 12
    [726] => 9
    [727] => 9
    [728] => 12
    [729] => 9
    [730] => 15
    [731] => 11
    [732] => 5
    [733] => 3
    [734] => 11
    [735] => 12
    [736] => 20
    [737] => 3
    [738] => 7
    [739] => 9
    [740] => 12
    [741] => 10
    [742] => 10
    [743] => 6
    [744] => 10
    [745] => 7
    [746] => 10
    [747] => 11
    [748] => 7
    [749] => 13
    [750] => 13
    [751] => 11
    [752] => 13
    [753] => 14
    [754] => 12
    [755] => 8
    [756] => 13
    [757] => 10
    [758] => 6
    [759] => 11
    [760] => 10
    [761] => 13
    [762] => 8
    [763] => 12
    [764] => 9
    [765] => 8
    [766] => 7
    [767] => 8
    [768] => 13
    [769] => 12
    [770] => 10
    [771] => 15
    [772] => 7
    [773] => 10
    [774] => 9
    [775] => 15
    [776] => 11
    [777] => 6
    [778] => 8
    [779] => 7
    [780] => 11
    [781] => 9
    [782] => 9
    [783] => 7
    [784] => 13
    [785] => 12
    [786] => 15
    [787] => 9
    [788] => 6
    [789] => 16
    [790] => 8
    [791] => 8
    [792] => 16
    [793] => 11
    [794] => 10
    [795] => 11
    [796] => 10
    [797] => 8
    [798] => 11
    [799] => 8
    [800] => 11
    [801] => 4
    [802] => 11
    [803] => 15
    [804] => 13
    [805] => 9
    [806] => 14
    [807] => 10
    [808] => 10
    [809] => 7
    [810] => 8
    [811] => 8
    [812] => 8
    [813] => 14
    [814] => 6
    [815] => 6
    [816] => 11
    [817] => 9
    [818] => 8
    [819] => 7
    [820] => 7
    [821] => 8
    [822] => 2
    [823] => 5
    [824] => 15
    [825] => 4
    [826] => 12
    [827] => 11
    [828] => 8
    [829] => 6
    [830] => 5
    [831] => 9
    [832] => 13
    [833] => 12
    [834] => 11
    [835] => 6
    [836] => 14
    [837] => 9
    [838] => 12
    [839] => 6
    [840] => 4
    [841] => 11
    [842] => 7
    [843] => 9
    [844] => 9
    [845] => 7
    [846] => 7
    [847] => 18
    [848] => 11
    [849] => 8
    [850] => 12
    [851] => 6
    [852] => 14
    [853] => 12
    [854] => 9
    [855] => 13
    [856] => 12
    [857] => 7
    [858] => 9
    [859] => 12
    [860] => 9
    [861] => 8
    [862] => 5
    [863] => 13
    [864] => 11
    [865] => 8
    [866] => 8
    [867] => 7
    [868] => 10
    [869] => 13
    [870] => 11
    [871] => 9
    [872] => 10
    [873] => 8
    [874] => 10
    [875] => 16
    [876] => 10
    [877] => 12
    [878] => 14
    [879] => 4
    [880] => 9
    [881] => 10
    [882] => 10
    [883] => 17
    [884] => 13
    [885] => 6
    [886] => 8
    [887] => 12
    [888] => 14
    [889] => 9
    [890] => 12
    [891] => 6
    [892] => 7
    [893] => 16
    [894] => 8
    [895] => 14
    [896] => 11
    [897] => 20
    [898] => 7
    [899] => 11
    [900] => 10
    [901] => 8
    [902] => 9
    [903] => 13
    [904] => 9
    [905] => 12
    [906] => 14
    [907] => 8
    [908] => 10
    [909] => 13
    [910] => 10
    [911] => 5
    [912] => 7
    [913] => 8
    [914] => 12
    [915] => 10
    [916] => 17
    [917] => 9
    [918] => 8
    [919] => 6
    [920] => 8
    [921] => 12
    [922] => 9
    [923] => 10
    [924] => 5
    [925] => 11
    [926] => 13
    [927] => 9
    [928] => 11
    [929] => 8
    [930] => 9
    [931] => 9
    [932] => 7
    [933] => 10
    [934] => 13
    [935] => 15
    [936] => 12
    [937] => 10
    [938] => 12
    [939] => 10
    [940] => 11
    [941] => 6
    [942] => 8
    [943] => 5
    [944] => 17
    [945] => 9
    [946] => 12
    [947] => 9
    [948] => 14
    [949] => 11
    [950] => 10
    [951] => 13
    [952] => 10
    [953] => 10
    [954] => 10
    [955] => 6
    [956] => 8
    [957] => 18
    [958] => 8
    [959] => 6
    [960] => 13
    [961] => 10
    [962] => 12
    [963] => 11
    [964] => 14
    [965] => 10
    [966] => 8
    [967] => 9
    [968] => 14
    [969] => 17
    [970] => 11
    [971] => 7
    [972] => 11
    [973] => 15
    [974] => 11
    [975] => 11
    [976] => 16
    [977] => 7
    [978] => 12
    [979] => 7
    [980] => 10
    [981] => 8
    [982] => 9
    [983] => 6
    [984] => 11
    [985] => 13
    [986] => 10
    [987] => 11
    [988] => 9
    [989] => 7
    [990] => 12
    [991] => 7
    [992] => 7
    [993] => 11
    [994] => 8
    [995] => 13
    [996] => 12
    [997] => 9
    [998] => 16
    [999] => 13
)

Is this generated with OpenSSL available on the system?

Yes it is:

$ php -i | grep -i openssl
SSL Version => OpenSSL/1.0.1f
openssl
OpenSSL support => enabled
OpenSSL Library Version => OpenSSL 1.0.1f 6 Jan 2014
OpenSSL Header Version => OpenSSL 1.0.1f 6 Jan 2014
OpenSSL support => enabled

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Uh-oh! Random number generator is not pseudorandom™ #130

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Uh-oh! Random number generator is not pseudorandom™ #130

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multiwebinc commented on Sep 9, 2014

xqus commented on Nov 3, 2014

multiwebinc commented on Nov 3, 2014

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