#38986 [Opn->Bgs]: Wrong example 1 -> Hash values of Password

ID: 38986 Updated by: colder@php.net Reported By: charlie28u798r at web dot de -Status: Open +Status: Bogus Bug Type: Documentation problem PHP Version: Irrelevant New Comment: Because the salt is random, the resulting hash will be random. To test this hash against an user input, you'll use $hash as the salt: if(crypt($input, $hash) == $hash) The hash can always be used as the salt: crypt($p, crypt($p, $salt)) == crypt($p, $salt) // true Example1 looks perfectly clear to me. Example2 is correct, apache handles crypt()'ed passwords. Previous Comments: ------------------------------------------------------------------------ [2006-09-28 20:49:31] charlie28u798r at web dot de Description: ------------ There are 2 examples given in the documentation of crypt(), which cant work the way their shown. Example 2 will, as read in the documentation, give a different hash values each time its called. But it looks like its supposed to give the same hash for same passwords so a user given password can be compared with the one saved in a databank (or the on in htpasswd). <?php // Set the password $password = 'mypassword'; // Get the hash, letting the salt be automatically generated $hash = crypt($password); ?> Reproduce code: --------------- On the other hand example 1 is not clear. This wont work either, unless $user_input is given and it won't really state what it should do. From the code i would state it should be used to compare passwords, but like i said its not clear. <?php $password = crypt('mypassword'); // let the salt be automatically generated /* You should pass the entire results of crypt() as the salt for comparing a password, to avoid problems when different hashing algorithms are used. (As it says above, standard DES-based password hashing uses a 2-character salt, but MD5-based hashing uses 12.) */ if (crypt($user_input, $password) == $password) { echo "Password verified!"; } else echo "Wrong Password"; ?> Expected result: ---------------- Password verified Actual result: -------------- Wrong Password ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=38986&edit=1