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authorGregory P. Smith <greg@mad-scientist.com>2005-08-21 18:45:59 +0000
committerGregory P. Smith <greg@mad-scientist.com>2005-08-21 18:45:59 +0000
commitf21a5f773964d34c7b6deb7e3d753fae2b9c70e2 (patch)
treeba3b66cea11da1d8e930555aa5a10f775a285d84 /Doc/lib/libhmac.tex
parent33a5f2af59ddcf3f1b0447a8dbd0576fd78de303 (diff)
downloadcpython-git-f21a5f773964d34c7b6deb7e3d753fae2b9c70e2.tar.gz
[ sf.net patch # 1121611 ]
A new hashlib module to replace the md5 and sha modules. It adds support for additional secure hashes such as SHA-256 and SHA-512. The hashlib module uses OpenSSL for fast platform optimized implementations of algorithms when available. The old md5 and sha modules still exist as wrappers around hashlib to preserve backwards compatibility.
Diffstat (limited to 'Doc/lib/libhmac.tex')
-rw-r--r--Doc/lib/libhmac.tex20
1 files changed, 13 insertions, 7 deletions
diff --git a/Doc/lib/libhmac.tex b/Doc/lib/libhmac.tex
index 1d49417853..5ca24d1c28 100644
--- a/Doc/lib/libhmac.tex
+++ b/Doc/lib/libhmac.tex
@@ -14,8 +14,10 @@ This module implements the HMAC algorithm as described by \rfc{2104}.
\begin{funcdesc}{new}{key\optional{, msg\optional{, digestmod}}}
Return a new hmac object. If \var{msg} is present, the method call
\code{update(\var{msg})} is made. \var{digestmod} is the digest
- module for the HMAC object to use. It defaults to the
- \refmodule{md5} module.
+ constructor or module for the HMAC object to use. It defaults to
+ the \code{\refmodule{hashlib}.md5} constructor. \note{The md5 hash
+ has known weaknesses but remains the default for backwards compatibility.
+ Choose a better one for your application.}
\end{funcdesc}
An HMAC object has the following methods:
@@ -29,14 +31,14 @@ An HMAC object has the following methods:
\begin{methoddesc}[hmac]{digest}{}
Return the digest of the strings passed to the \method{update()}
- method so far. This is a 16-byte string (for \refmodule{md5}) or a
- 20-byte string (for \refmodule{sha}) which may contain non-\ASCII{}
- characters, including NUL bytes.
+ method so far. This string will be the same length as the
+ \var{digest_size} of the digest given to the constructor. It
+ may contain non-\ASCII{} characters, including NUL bytes.
\end{methoddesc}
\begin{methoddesc}[hmac]{hexdigest}{}
- Like \method{digest()} except the digest is returned as a string of
- length 32 for \refmodule{md5} (40 for \refmodule{sha}), containing
+ Like \method{digest()} except the digest is returned as a string
+ twice the length containing
only hexadecimal digits. This may be used to exchange the value
safely in email or other non-binary environments.
\end{methoddesc}
@@ -46,3 +48,7 @@ An HMAC object has the following methods:
efficiently compute the digests of strings that share a common
initial substring.
\end{methoddesc}
+
+\begin{seealso}
+ \seemodule{hashlib}{The python module providing secure hash functions.}
+\end{seealso}