Difference between revisions of "Ns sha1"
(added additional links to alternative sha1 implementations (non-aolserver)) |
(additional information on salt usage -- perhaps here not the best place for it) |
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| − | Usually this function is used with a salt, as without a salt it is succeptible to dictionary-based attacks. | + | Usually this function is used with either a prefixed or postfixed salt, as without a salt it is succeptible to dictionary-based attacks. |
Example 2: | Example 2: | ||
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</pre> | </pre> | ||
| − | This function is provided by the [[nssha1]] module. | + | Good salts are at least of moderate length and consist of random characters. Take note, however, that you would need to be able to retrieve the same salt to perform a match against the previous hash given the same unsalted input. Hash functions for human-chosen alphanumeric passwords are usually succeptible to dictionary-based attacks. |
| + | |||
| + | This function is provided by the [[nssha1]] module, provided as a [http://packages.debian.org/stable/web/aolserver4-nssha1 Debian package] among others. | ||
Unfortunately, this implementation does not seem to be immediately compatible with [http://www.xml-dev.com/blog/sha1.php other] SHA1 [http://www.movable-type.co.uk/scripts/SHA-1.html implementations]. | Unfortunately, this implementation does not seem to be immediately compatible with [http://www.xml-dev.com/blog/sha1.php other] SHA1 [http://www.movable-type.co.uk/scripts/SHA-1.html implementations]. | ||
Revision as of 15:15, 3 December 2005
Function
ns_sha1 string
Description
Returns a 40-character, hex-encoded string containing the SHA1 hash of the first argument.
Usage
Example 1:
set sRawPassword "mypassword" set sPassword [ns_sha1 $sRawPassword] ns_adp_puts $sPassword # 04003622EB9D0F788CE7568C7EED23809534365A
Usually this function is used with either a prefixed or postfixed salt, as without a salt it is succeptible to dictionary-based attacks.
Example 2:
set sSalt "salty"
set sRawPassword "mypassword"
set sPassword [ns_sha1 ${sRawPassword}${sSalt}]
# B48FB74597C11FC609DBE912992085EB07847FB6
Good salts are at least of moderate length and consist of random characters. Take note, however, that you would need to be able to retrieve the same salt to perform a match against the previous hash given the same unsalted input. Hash functions for human-chosen alphanumeric passwords are usually succeptible to dictionary-based attacks.
This function is provided by the nssha1 module, provided as a Debian package among others.
Unfortunately, this implementation does not seem to be immediately compatible with other SHA1 implementations.
Postgresql:
template1=> select encode(digest('mypassword','SHA1'),'hex');
encode
------------------------------------------
91dfd9ddb4198affc5c194cd8ce6d338fde470e2
(1 row)
SEE ALSO
