php help: decrypting

[Rammer]

i DID search this forum for this topic. nothing of interest came up.

i was wondering, is there a built-in php function that could decrypt an md5-encrypted string, or would i have to write some weird algorithm to decode one? if it is the latter, don't bother explaining it if you know how, because i don't want to bother you.

[DFox]

No, there's no built in function.

It's a very hard thing to do, and if the decrypted string was formed from a well made password, at best you'll find a collision, but you're not going to be able to decrypt it.

[Rammer]

At 8/26/06 09:02 PM, DFox2 wrote: No, there's no built in function.

It's a very hard thing to do, and if the decrypted string was formed from a well made password, at best you'll find a collision, but you're not going to be able to decrypt it.

ah, well, thank you for that.

i wouldn't have to guess the string, in fact, it is on a database on my site.

[DFox]

At 8/26/06 09:04 PM, 2k_rammerizkool wrote: i wouldn't have to guess the string, in fact, it is on a database on my site.

What do you mean?

If you just want to compare a non-encrypted string to an encrypted one, just do an md5() on the non encrypted, and they can be compared. If that's what you mean.

[JeremysFilms]

This holds some relevance, so if you want to decrypt an md5 hash, you could check out this site:
http://www.md5decrypter.com/

[Taylor]

Rainbow tables.

[Rammer]

At 8/26/06 11:39 PM, JeremysFilms wrote: This holds some relevance, so if you want to decrypt an md5 hash, you could check out this site:
http://www.md5decrypter.com/

i tried it...i would think that it only works for single characters. these hashes are words, though.

DFox2
What do you mean?

i meant, the md5-encrypted string is on a database. i should have clarified that.

[DFox]

At 8/27/06 12:12 AM, 2k_rammerizkool wrote: i tried it...i would think that it only works for single characters. these hashes are words, though.

Yeah that decrypted only uses strings that people have entered in it's database before. It's not actually decrypting the hash, it's just trying to see if someone submitted that encrypted hash before.

[Rammer]

At 8/27/06 12:08 AM, taylorwilsdon wrote: Rainbow tables.

*cough*, what is a rainbow table?

[DFox]

At 8/27/06 12:19 AM, 2k_rammerizkool wrote:

At 8/27/06 12:08 AM, taylorwilsdon wrote: Rainbow tables.

*cough*, what is a rainbow table?

http://en.wikipedia.org/wiki/Rainbow_table

[Rammer]

At 8/27/06 12:20 AM, DFox2 wrote:

At 8/27/06 12:19 AM, 2k_rammerizkool wrote:

At 8/27/06 12:08 AM, taylorwilsdon wrote: Rainbow tables.

*cough*, what is a rainbow table?

http://en.wikipedia.org/wiki/Rainbow_table

i figured that's what it was. it doesn't seem very useful in this case...one letter can be a whole hash, and i have no clue how the encryption works for md5, despite wikipedia's explanation. so i wouldn't be able to find what i needed, especially when changing "the quick red fox jumped over the lazy brown dog" to "the quick red fox jumped over the lazy brown cog" changes the entire hash.

[WoogieNoogie]

Could I ask what you're wanting this for? Like, is it for a user seeing their password in their control panel or whatever?