Roman Ivanov wrote:
Ilia Alshanetsky wrote:
You cannot give it
an md5 and have it generate you a string with the same md5 hash, so md5
is still relatively safe.
http://www.google.com/search?q=md5+hash+lookup&start=0&start=0&ie=utf-8&oe=utf-8&client=firefox-a&rls=org.mozilla:en-US:official
I'd take that link with a grain of salt. :) Dictionary attack is
dangerous regardless of which hash function you use. That is when you
don't use a salt.
But md5 safeness depends on the purpose. It's use as a one way function
hasn't been compromised (yet), but the ability to generate collisions
means that it cannot be used to generate a fingerprint to detect
malicious tampering. In my country we have legally binding digital
signatures that currently use sha-1 to generate the fingerprint to sign
and the weakening of sha-1's collision generation resistance is a bit
unnerving. Fortunately the attacks are still too expensive to be useful,
but I'm currently lobbying to have better hashes implemented.
It would be nice to have the default PHP install be able to atleast
verifiy digitally signed files.
Ants Aasma
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
