Hash()

edit

Returns the one-way hash of a variable-length input string based on the algorithm, producing a fixed-length string.

A one-way hash cannot be reversed back to the original input except by a brute force attack.

Hash( input=any, algorithm=string, encoding=string, numIterations=number );

Returns: String

Argument Description
input
any, required 		edit

String to hash.

Alias: string
algorithm
string, optional 		edit

The algorithm to use for hashing your input. The following values are supported:

  • QUICK: Generates a 15 or 16-character, hexadecimal string. This algorithm provides fast hashing but offers no cryptographic security.
  • MD5: Generates a 32-character string using the MD5 algorithm. This algorithm is considered cryptographically broken and unsuitable for further cryptographical use.
  • CFMX_COMPAT: Deprecated. Lucee uses the MD5 algorithm instead.
  • SHA: Generates a 40-character string using the Secure Hash Algorithm, SHA-1, specified by National Institute of Standards and Technology (NIST) in the FIPS-180-2 standard. Cryptographic weaknesses were discovered in SHA-1, and the standard is no longer approved for most cryptographic uses.
  • SHA-256: Generates a 64-character string using the SHA-256 algorithm specified by the FIPS-180-2 standard.
  • SHA-384: Generates a 96-character string using the SHA-384 algorithm specified by the FIPS-180-2 standard.
  • SHA-512: Generates an 128-character string using the SHA-512 algorithm specified by the FIPS-180-2 standard.

The default value is MD5.
encoding
string, optional 		edit

The encoding to use when converting the input string to byte data.
numIterations
number, optional 		edit

The number of times to iterate hashing. A greater number of iterations will result in a cryptographically stronger hash but will also take more time to generate that hash.

The default value is 1.

Examples

edit 
// Variable-length strings produce fixed-length hashes.
input = 'Hello World';
dump( hash( input ) ); // B10A8DB164E0754105B7A99BE72E3FE5

input = 'Mary had a little lamb.';
dump( hash( input ) ); // CA964B1677D5476EA11EED1E1837C342


// Different algorithms are supported.
input = 'Hello World';
dump( hash( input ) ); // B10A8DB164E0754105B7A99BE72E3FE5
dump( hash( input, 'QUICK' ) ); // 6b736ba1c9a95606
dump( hash( input, 'MD5' ) ); // B10A8DB164E0754105B7A99BE72E3FE5
dump( hash( input, 'CFMX_COMPAT' ) ); // B10A8DB164E0754105B7A99BE72E3FE5
dump( hash( input, 'SHA' ) ); // 0A4D55A8D778E5022FAB701977C5D840BBC486D0
dump( hash( input, 'SHA-256' ) ); // A591A6D40BF420404A011733CFB7B190D62C65BF0BCDA32B57B277D9AD9F146E
dump( hash( input, 'SHA-384' ) ); // 99514329186B2F6AE4A1329E7EE6C610A729636335174AC6B740F9028396FCC803D0E93863A7C3D90F86BEEE782F4F3F
dump( hash( input, 'SHA-512' ) ); // 2C74FD17EDAFD80E8447B0D46741EE243B7EB74DD2149A0AB1B9246FB30382F27E853D8585719E0E67CBDA0DAA8F51671064615D645AE27ACB15BFB1447F459B

// The default, MD5 and CFMX_COMPAT algorithms are all MD5.
dump( hash( input ) == hash( input, 'MD5' ) && hash( input, 'MD5' ) == hash( input, 'CFMX_COMPAT' ) ); // true


input = 'Hello World';

// The number of iterations change the hash
dump( hash( input = input, numIterations = 1 ) ); // B10A8DB164E0754105B7A99BE72E3FE5
dump( hash( input = input, numIterations = 9 ) ); // 5E1C304FD939BBE1378ED977E2AD26B5

// numIterations less than 1 are set to 1
dump( hash( input = input, numIterations = 0 ) == hash( input = input, numIterations = 1 ) ); // true

// More iterations take more time
timer type='inline' label='1000 SHA-512s, 1 iteration each' {
    for ( i = 0; i < 1000; i++ ) {
        hash( input = input, algorithm = 'SHA-512', numIterations = 1 );
    }
    // 1000 SHA-512s, 1 iteration each: 5ms
};

writeOutput('<br>');

timer type='inline' label='1000 SHA-512s, 10 iterations each' {
    for ( i = 0; i < 1000; i++ ) {
        hash( input = input, algorithm = 'SHA-512', numIterations = 10 );
    }
    // 1000 SHA-512s, 10 iterations each: 21ms
};

See also