[PHP] Re: Is there a function can decrypt md5 ??
Brad Chow escreveu: Dear all: Is there a function can decrypt md5 ?? I don't have any bad ideas. I just want to know whether md5 can be decrypted or not. -- Brad -- The md5 hash is not a codification, but, yes, a validation key. In this way, it cannot be decoded! It only can be used to validate data, like a signature. - zerof -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: Is there a function can decrypt md5 ??
- Original Message - From: zerof [EMAIL PROTECTED] To: php-general@lists.php.net Sent: Tuesday, October 24, 2006 6:00 PM Subject: [PHP] Re: Is there a function can decrypt md5 ?? Brad Chow escreveu: Dear all: Is there a function can decrypt md5 ?? I don't have any bad ideas. I just want to know whether md5 can be decrypted or not. -- Brad -- The md5 hash is not a codification, but, yes, a validation key. In this way, it cannot be decoded! It only can be used to validate data, like a signature. - zerof I don't think this explains why it cannot be decodified, one thing does not result from the other. An analogy of why it cannot be decodified is thinking of the MD5 as the remainder of a division. Even if you know the divisor and the remainder, there are many numbers that could have produced that result. The remainder or modulo operation loses information thus the original cannot be reconstructed. It is a one way operation, while the same number will always produce the same MD5, many numbers can be the origin of that result and which one was it cannot be guessed. While dividing by 2 will only give you reminders of 0 and 1 for every number, the result of Md5 produces a very good variety of results with a good spread of values over the whole range of possible results. Satyam -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Re: Is there a function can decrypt md5 ??
Satyam escreveu: An analogy of why it cannot be decodified is thinking of the MD5 as the remainder of a division. Even if you know the divisor and the remainder, there are many numbers that could have produced that result. The remainder or modulo operation loses information thus the original cannot be reconstructed. It is a one way operation, while the same number will always produce the same MD5, many numbers can be the origin of that result and which one was it cannot be guessed. While dividing by 2 will only give you reminders of 0 and 1 for every number, the result of Md5 produces a very good variety of results with a good spread of values over the whole range of possible results. Satyam You are absolutely correct. What I wanted to say is that hash md5 does not have to be used to encrypt nothing, therefore, this is not its purpose. -- ex-corde, zerof -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
