mirror of
https://github.com/python/cpython.git
synced 2025-10-31 21:51:50 +00:00
66 lines
2.1 KiB
TeX
66 lines
2.1 KiB
TeX
\section{Built-in Module \sectcode{md5}}
|
|
\label{module-md5}
|
|
\rfcindex{1321}
|
|
\bimodindex{md5}
|
|
|
|
This module implements the interface to RSA's MD5 message digest
|
|
algorithm (see also Internet \rfc{1321}). Its use is quite
|
|
straightforward:\ use the \code{md5.new()} to create an md5 object.
|
|
You can now feed this object with arbitrary strings using the
|
|
\code{update()} method, and at any point you can ask it for the
|
|
\dfn{digest} (a strong kind of 128-bit checksum,
|
|
a.k.a. ``fingerprint'') of the contatenation of the strings fed to it
|
|
so far using the \code{digest()} method.
|
|
|
|
For example, to obtain the digest of the string {\tt"Nobody inspects
|
|
the spammish repetition"}:
|
|
|
|
\bcode\begin{verbatim}
|
|
>>> import md5
|
|
>>> m = md5.new()
|
|
>>> m.update("Nobody inspects")
|
|
>>> m.update(" the spammish repetition")
|
|
>>> m.digest()
|
|
'\273d\234\203\335\036\245\311\331\336\311\241\215\360\377\351'
|
|
\end{verbatim}\ecode
|
|
%
|
|
More condensed:
|
|
|
|
\bcode\begin{verbatim}
|
|
>>> md5.new("Nobody inspects the spammish repetition").digest()
|
|
'\273d\234\203\335\036\245\311\331\336\311\241\215\360\377\351'
|
|
\end{verbatim}\ecode
|
|
%
|
|
\renewcommand{\indexsubitem}{(in module md5)}
|
|
|
|
\begin{funcdesc}{new}{\optional{arg}}
|
|
Return a new md5 object. If \var{arg} is present, the method call
|
|
\code{update(\var{arg})} is made.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{md5}{\optional{arg}}
|
|
For backward compatibility reasons, this is an alternative name for the
|
|
\code{new()} function.
|
|
\end{funcdesc}
|
|
|
|
An md5 object has the following methods:
|
|
|
|
\renewcommand{\indexsubitem}{(md5 method)}
|
|
\begin{funcdesc}{update}{arg}
|
|
Update the md5 object with the string \var{arg}. Repeated calls are
|
|
equivalent to a single call with the concatenation of all the
|
|
arguments, i.e.\ \code{m.update(a); m.update(b)} is equivalent to
|
|
\code{m.update(a+b)}.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{digest}{}
|
|
Return the digest of the strings passed to the \code{update()}
|
|
method so far. This is an 16-byte string which may contain
|
|
non-\ASCII{} characters, including null bytes.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{copy}{}
|
|
Return a copy (``clone'') of the md5 object. This can be used to
|
|
efficiently compute the digests of strings that share a common initial
|
|
substring.
|
|
\end{funcdesc}
|