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14.14.4 Hash Functions

Cryptographic hash functions are essential for many cryptographic applications, and are also useful in other contexts. The Toolkit includes the two most common, MD5 and SHA1. They have the same methods.

METHOD
update

SYNTAX
object o->update(string data);

DESCRIPTION
Processes some more data. For convenience, this method returns the object itself.

METHOD
digest

SYNTAX
string o->digest();

DESCRIPTION
Returns the hash value, or message digest, corresponding to all the data that was previously passed to the update method. Also resets the hash object, so that it can be used to process a new message.

METHOD
query_digest_size

SYNTAX
int o->query_digest_size();

DESCRIPTION
Returns the size, in octets, of the digests produced by this hash function.
To get the md5 hash of a string s, you would use
Crypto.md5()->update(s)->digest()

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