HMAC md5 encryption/decryption in PHP

Question

I have the php code for making HMAC md5 encryption

$input = 'foo';
$output = hash_hmac('md5', $input, $secretKey);

After making the hash,is there anyway I could get the $input back to text form.

score 1 · Answer 1 · answered May 14 '14 at 14:41

1

The difference between encryption (which MD5 is not) and hashing is that hashing is unidirectional. The answer is no.

answered May 14 '14 at 14:41

lafor

So why actually hashing is used?And why does key is used? – user3637105 May 14 '14 at 14:43
1

@user3637105 http://en.wikipedia.org/wiki/Cryptographic_hash_function#Applications – lafor May 14 '14 at 14:45

1 Answers1