diff --git a/reference/strings/functions/crypt.xml b/reference/strings/functions/crypt.xml index 258e130e8d..5c57176c23 100644 --- a/reference/strings/functions/crypt.xml +++ b/reference/strings/functions/crypt.xml @@ -3,7 +3,7 @@ crypt - One-way string encryption (hashing) + One-way string hashing @@ -14,25 +14,23 @@ stringsalt - crypt will return an encrypted string using the - standard Unix DES-based encryption algorithm or + crypt will return a hashed string using the + standard Unix DES-based algorithm or alternative algorithms that may be available on the system. - Some operating systems support more than one type of encryption. In - fact, sometimes the standard DES-based encryption is replaced by an - MD5-based encryption algorithm. The encryption type is triggered by the - salt argument. At install time, PHP determines the capabilities of the - crypt function and will accept salts for other encryption types. If no - salt is provided, PHP will auto-generate a standard two character salt by - default, unless the default encryption type on the system is MD5, in - which case a random MD5-compatible salt is generated. PHP sets a - constant named CRYPT_SALT_LENGTH which tells you - whether a regular two character salt applies to your system or the longer - twelve character salt is applicable. + Some operating systems support more than one type of hash. In + fact, sometimes the standard DES-based algorithm is replaced by an + MD5-based algorithm. The hash type is triggered by the salt argument. + Prior to 5.3, PHP would determine the available algorithms at install-time + based on the system's crypt(). If no salt is provided, PHP will + auto-generate either a standard two character (DES) salt, or a twelve + character (MD5), depending on the availability of MD5 crypt(). PHP sets a + constant named CRYPT_SALT_LENGTH which indicates the + longest valid salt allowed by the available hashes. - The standard DES-based encryption crypt returns the + The standard DES-based crypt returns the salt as the first two characters of the output. It also only uses the first eight characters of str, so longer strings that start with the same eight characters will generate the same result @@ -40,18 +38,18 @@ On systems where the crypt() function supports multiple - encryption types, the following constants are set to 0 or 1 + hash types, the following constants are set to 0 or 1 depending on whether the given type is available: - CRYPT_STD_DES - Standard DES-based encryption with a two character salt + CRYPT_STD_DES - Standard DES-based hash with a two character salt - CRYPT_EXT_DES - Extended DES-based encryption. The "salt" is a + CRYPT_EXT_DES - Extended DES-based hash. The "salt" is a 9-character string consisting of an underscore followed by 4 bytes of iteration count and 4 bytes of salt. These are encoded as printable characters, 6 bits per character, least significant character first. The values 0 to 63 are encoded as "./0-9A-Za-z". @@ -59,37 +57,37 @@ - CRYPT_MD5 - MD5 encryption with a twelve character salt starting with + CRYPT_MD5 - MD5 hashing with a twelve character salt starting with $1$ - CRYPT_BLOWFISH - Blowfish encryption with a salt as follows: + CRYPT_BLOWFISH - Blowfish hashing with a salt as follows: "$2a$", a two digit cost parameter, "$", and 22 base 64 digits from the alphabet "./0-9A-Za-z". Using characters outside of this range in the salt will cause crypt() to return a zero-length string. The two digit cost parameter is the base-2 logarithm of the iteration count for the underlying Blowfish-based hashing algorithmeter and must be in - range 04-31, values outside this range will cause crypt() to select DES-based encryption - instead, with a salt of '$2'. + range 04-31, values outside this range will cause crypt() to select DES instead, with a salt + of '$2'. - CRYPT_SHA256 - SHA-256 encryption with a sixteen character salt + CRYPT_SHA256 - SHA-256 hash with a sixteen character salt prefixed with $5$. If the salt string starts with 'rounds=<N>$', the numeric value of N is used to indicate how many times the hashing loop should be executed, much like the cost - parameter on Blowfish encryption. The default number of rounds is 5000, there is a minimum of + parameter on Blowfish. The default number of rounds is 5000, there is a minimum of 1000 and a maximum of 999,999,999. Any selection of N outside this range will be truncated to the nearest limit. - CRYPT_SHA512 - SHA-512 encryption with a sixteen character salt + CRYPT_SHA512 - SHA-512 hash with a sixteen character salt prefixed with $6$. If the salt string starts with 'rounds=<N>$', the numeric value of N is used to indicate how many times the hashing loop should be executed, much like the cost - parameter on Blowfish encryption. The default number of rounds is 5000, there is a minimum of + parameter on Blowfish. The default number of rounds is 5000, there is a minimum of 1000 and a maximum of 999,999,999. Any selection of N outside this range will be truncated to the nearest limit. @@ -111,7 +109,7 @@ str - The string to be encrypted. + The string to be hashed. @@ -119,7 +117,7 @@ salt - An optional salt string to base the encryption on. If not provided, + An optional salt string to base the hashing on. If not provided, one will be randomly generated by PHP each time you call this function. @@ -136,7 +134,7 @@ &reftitle.returnvalues; - Returns the encrypted string. + Returns the hashed string. @@ -213,7 +211,7 @@ $hash = crypt($password); - Using <function>crypt</function> with different encryption types + Using <function>crypt</function> with different hash types