Rafael
27 de Noviembre del 2003

Porfavor necesito saber como puedo crear password aleatorios en Php de forma segura

crash
27 de Noviembre del 2003

puedes usar el rand
ademas usar un arreglo de letras ,para generar letras y numero
for($i="a";$i<="z";$i++){
$arreglo[$cont]=$i;
$cont++}
espero te de una idea

Rafael
27 de Noviembre del 2003

Muchas gracias por tu ayuda.

Rub?
27 de Noviembre del 2003

Usa la funcion md5 con microtime. Si los quieres mas cortos, usa substr para cortarlo.

Zerokiller
27 de Noviembre del 2003

randchar.php
<?php

/**
* randchar() - generate arbitrary length string of random characters
* or random, decimal/hexadecimal rgb/gray color values
* Copyright (C) 2003 Erich Spencer <[email protected]>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License (http://www.gnu.org/licenses/gpl.txt)
* for more details.
*
*
* Description:
*
* mixed randchar ( [int length, string range, string case] )
*
* randchar() returns a string or number with $length number of
* characters or digits, from a $range set of possible character
* values, in $case character case.
*
* If arguments are invalid or missing, $length defaults to 8,
* $range defaults to alphanumeric, and $case defaults to mixed.
*
* Four special instances of $range are provided to produce decimal
* or hexadecimal rgb, or grayscale color values for $length bit
* color depth. Currently, randchar() supports 24 bit color depth
* maximum, so $length defaults to 8 if greater than 24.
*
* Possible values for $range are
*
* abc = alphabetic
* anc = alphanumeric
* hxd = hexadecimal
* nmc = numeric
*
* dmc = color: decimal
* dmg = gray : decimal
* hxc = color: hexadecimal
* hxg = gray : hexadecimal
*
* Possible values for $case are
*
* l = lower
* u = upper
* m = mixed
*
* -------------------------------------------------------------
*
* CREATED 2003-04-30
* REVISED 2003-05-28
* VERSION 0.5.20030528
*
*/

function randchar($length, $range, $case)
{
$str = NULL;
if (gettype($length) != 'integer')
$length = 8;
switch ($range) {
case 'abc': // alphabetic
$minval = 2; $maxval = 3;
break;
case 'dmc': // color: decimal
case 'hxc': // color: hexadecimal
$minval = 5; $maxval = 5;
if ($length > 24) $length = 24;
$depth = $length;
$length = 6;
break;
case 'dmg': // gray: decimal
case 'hxg': // gray: hexadecimal
$minval = 5; $maxval = 5;
if ($length > 24) $length = 24;
$depth = $length;
$length = 2;
break;
case 'hxd': // hexadecimal
$minval = 5; $maxval = 5;
break;
case 'nmc': // numeric
$minval = 1; $maxval = 1;
break;
case 'anc': // alphanumeric
default : // alphanumeric
$minval = 1; $maxval = 4;
break;
}
for($i = 0;$i < $length;$i++) {
switch (@rand($minval, $maxval)) {
case 1: $str .= chr(rand(48, 57)); // 0-9
break;
case 2: $str .= chr(rand(97, 122)); // a-z
break;
case 3: $str .= chr(rand(65, 90)); // A-Z
break;
case 4: $str .= chr(rand(48, 57)); // 0-9
break;
case 5: $str .= dechex(rand(0,15)); // 0-16
break;
}
}
switch ($range) { // procedure for color values
case 'dmc':
case 'dmg':
case 'hxc':
case 'hxg':
$clrs = chunk_split($str,2,' '); // space delimit color value pairs
$clrs = explode(' ',trim($clrs)); // load color value pairs into array
$bpclr = floor($depth/3); // set number of bits per color value
$step = (256/pow(2,$bpclr)); // calculate step value for quantizing
foreach($clrs as $key => $clr) {
$clrs[$key] = hexdec($clr); // convert to decimal for manipulation
$clr = round($clrs[$key] / $step); // calculate quantizing (Q) factor
$clr = $clr * $step; // multiply color value by Q factor
$clr = $clr - floor($clr/256); // adjust to maintain bounds 0-256
$clrs[$key] = $clr; // replace original color value pair
}
switch ($range) { // triple gray value
case 'dmg':
case 'hxg':
$clrs = array_pad($clrs,3,$clrs[0]);
break;
}
switch ($range) {
case 'dmc': // rrr,ggg,bbb
case 'dmg': // rrr,ggg,bbb
$str = (
$clrs[0].","
.$clrs[1].","
.$clrs[2]
);
break;
case 'hxc': // rrggbb
case 'hxg': // rrggbb
$str = (
sprintf("%02s",dechex($clrs[0]))
.sprintf("%02s",dechex($clrs[1]))
.sprintf("%02s",dechex($clrs[2]))
);
break;
}
break;
}
switch ($case) {
case 'l': // lower case
$str = strtolower($str);
break;
case 'u': // upper case
$str = strtoupper($str);
break;
}
return $str;
}

?>

----------

el llamado lo haces asi:
<?php
require_once('randchar.php');
$largo = 8; #8 caracteres.
$rango = anc; #Alfanumérico.
$case = m; #Mezcla minúsculas y mayúsculas.

$lost_pass = randchar($largo, $rango, $case);
?>

Los valores para el rango y el case están descritos más arriba.

Suerte.