Question

What is difference in CodeIgniter sha1 and normal PHP sha1?
For example:

$codeigniter_hashed = $this -> encrypt -> sha1( "test" );

And

$normal_hashed = sha1("test");

Both will return same values.
Where does CodeIgniter uses encryption_key?

Answer 1

If your PHP installation doesn’t have sha1 installed, you can use the CI version. If your PHP installation already has it, you don’t need to use the CI function.

From the user guide:

$this->encrypt->sha1();

SHA1 encoding function. Provide a
string and it will return a 160 bit
one way hash. Note: SHA1, just like
MD5 is non-decodable. Example: $hash =
$this->encrypt->sha1('Some string');

Many PHP installations have SHA1
support by default so if all you need
is to encode a hash it’s simpler to
use the native function: $hash =
sha1('Some string');

If your server does not support SHA1
you can use the provided function.

More info: http://codeigniter.com/user_guide/libraries/encryption.html