PHP Function Hash_PBKDF2
Hashing function is used to check if two strings are equal. The string is divided into a number of segments and each segment is compared with the target string. If the string is not equal to the target it will return FALSE. This is a common method used in web application security to protect against attacks and vulnerabilities.
The php function hash_pbkdf2 takes a password and generates a binary key which is double the size of the original password. The algorithm takes into account a salt and the number of iterations so that if the password is known then it will be hard to decipher the key using brute force methods. This is a great solution for applications that require passwords to be encrypted because it prevents unauthorized access to the database.
This function uses the openssl_pbkdf2 adapter which is part of the pgp library. The pgp library is a library of functions that provide cryptographical services to PHP programs.
openssl_pbkdf2 computes PBKDF2 (Password-Based Key Derivation Function 2), a key derivation function defined in PKCS5 v2. It recommends a crytographic salt and a number of iterations. The derived key is returned as a raw binary string or false on failure.
The hash_pbkdf2() function takes six parameters, as follows: $algo – name of the selected hashing algorithm (like "md5", "sha256", "sha1"). $password – the password that will be used to create the PBKDF2 key derivation. $salt – a salt value that is a random per-session secret. $itr – the number of internal iterations to be performed. The derived key is returned as hex data or, if $raw_output is set to TRUE, in raw binary form.