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diff --git a/api/2.6/Crypto.Cipher.blockalgo-module.html b/api/2.6/Crypto.Cipher.blockalgo-module.html new file mode 100644 index 0000000..4bf4ab5 --- /dev/null +++ b/api/2.6/Crypto.Cipher.blockalgo-module.html @@ -0,0 +1,385 @@ +<?xml version="1.0" encoding="ascii"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + <title>Crypto.Cipher.blockalgo</title> + <link rel="stylesheet" href="epydoc.css" type="text/css" /> + <script type="text/javascript" src="epydoc.js"></script> +</head> + +<body bgcolor="white" text="black" link="blue" vlink="#204080" + alink="#204080"> +<!-- ==================== NAVIGATION BAR ==================== --> +<table class="navbar" border="0" width="100%" cellpadding="0" + bgcolor="#a0c0ff" cellspacing="0"> + <tr valign="middle"> + <!-- Home link --> + <th> <a + href="Crypto-module.html">Home</a> </th> + + <!-- Tree link --> + <th> <a + href="module-tree.html">Trees</a> </th> + + <!-- Index link --> + <th> <a + href="identifier-index.html">Indices</a> </th> + + <!-- Help link --> + <th> <a + href="help.html">Help</a> </th> + + <!-- Project homepage --> + <th class="navbar" align="right" width="100%"> + <table border="0" cellpadding="0" cellspacing="0"> + <tr><th class="navbar" align="center" + ><a href="http://www.pycrypto.org/">PyCrypto.org</a></th> + </tr></table></th> + </tr> +</table> +<table width="100%" cellpadding="0" cellspacing="0"> + <tr valign="top"> + <td width="100%"> + <span class="breadcrumbs"> + <a href="Crypto-module.html">Package Crypto</a> :: + <a href="Crypto.Cipher-module.html">Package Cipher</a> :: + Module blockalgo + </span> + </td> + <td> + <table cellpadding="0" cellspacing="0"> + <!-- hide/show private --> + <tr><td align="right"><span class="options" + >[<a href="frames.html" target="_top">frames</a + >] | <a href="Crypto.Cipher.blockalgo-module.html" + target="_top">no frames</a>]</span></td></tr> + </table> + </td> + </tr> +</table> +<!-- ==================== MODULE DESCRIPTION ==================== --> +<h1 class="epydoc">Module blockalgo</h1><p class="nomargin-top"></p> +Module with definitions common to all block ciphers. + +<!-- ==================== CLASSES ==================== --> +<a name="section-Classes"></a> +<table class="summary" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Classes</span></td> +</tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo.BlockAlgo-class.html" class="summary-name">BlockAlgo</a><br /> + Class modelling an abstract block cipher. + </td> + </tr> +</table> +<!-- ==================== VARIABLES ==================== --> +<a name="section-Variables"></a> +<table class="summary" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Variables</span></td> +</tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_ECB" class="summary-name">MODE_ECB</a> = <code title="1">1</code><br /> + <em>Electronic Code Book (ECB)</em>. +This is the simplest encryption mode. Each of the plaintext blocks +is directly encrypted into a ciphertext block, independently of +any other block. This mode exposes frequency of symbols +in your plaintext. Other modes (e.g. <em>CBC</em>) should be used instead. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_CBC" class="summary-name">MODE_CBC</a> = <code title="2">2</code><br /> + <em>Cipher-Block Chaining (CBC)</em>. Each of the ciphertext blocks depends +on the current and all previous plaintext blocks. An Initialization Vector +(<em>IV</em>) is required. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_CFB" class="summary-name">MODE_CFB</a> = <code title="3">3</code><br /> + <em>Cipher FeedBack (CFB)</em>. This mode is similar to CBC, but it transforms +the underlying block cipher into a stream cipher. Plaintext and ciphertext +are processed in <em>segments</em> of <strong>s</strong> bits. The mode is therefore sometimes +labelled <strong>s</strong>-bit CFB. An Initialization Vector (<em>IV</em>) is required. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a name="MODE_PGP"></a><span class="summary-name">MODE_PGP</span> = <code title="4">4</code><br /> + This mode should not be used. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_OFB" class="summary-name">MODE_OFB</a> = <code title="5">5</code><br /> + <em>Output FeedBack (OFB)</em>. This mode is very similar to CBC, but it +transforms the underlying block cipher into a stream cipher. +The keystream is the iterated block encryption of an Initialization Vector (<em>IV</em>). + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_CTR" class="summary-name">MODE_CTR</a> = <code title="6">6</code><br /> + <em>CounTeR (CTR)</em>. This mode is very similar to ECB, in that +encryption of one block is done independently of all other blocks. +Unlike ECB, the block <em>position</em> contributes to the encryption and no +information leaks about symbol frequency. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a href="Crypto.Cipher.blockalgo-module.html#MODE_OPENPGP" class="summary-name">MODE_OPENPGP</a> = <code title="7">7</code><br /> + OpenPGP. This mode is a variant of CFB, and it is only used in PGP and <a class="rst-reference external" href="http://tools.ietf.org/html/rfc4880" target="_top">OpenPGP</a> applications. +An Initialization Vector (<em>IV</em>) is required. + </td> + </tr> +<tr> + <td width="15%" align="right" valign="top" class="summary"> + <span class="summary-type"> </span> + </td><td class="summary"> + <a name="__package__"></a><span class="summary-name">__package__</span> = <code title="'Crypto.Cipher'"><code class="variable-quote">'</code><code class="variable-string">Crypto.Cipher</code><code class="variable-quote">'</code></code> + </td> + </tr> +</table> +<!-- ==================== VARIABLES DETAILS ==================== --> +<a name="section-VariablesDetails"></a> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr bgcolor="#70b0f0" class="table-header"> + <td align="left" colspan="2" class="table-header"> + <span class="table-header">Variables Details</span></td> +</tr> +</table> +<a name="MODE_ECB"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_ECB</h3> + <p><em>Electronic Code Book (ECB)</em>. +This is the simplest encryption mode. Each of the plaintext blocks +is directly encrypted into a ciphertext block, independently of +any other block. This mode exposes frequency of symbols +in your plaintext. Other modes (e.g. <em>CBC</em>) should be used instead.</p> +<p>See <a class="rst-reference external" href="http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf" target="_top">NIST SP800-38A</a> , Section 6.1 .</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +1 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<a name="MODE_CBC"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_CBC</h3> + <p><em>Cipher-Block Chaining (CBC)</em>. Each of the ciphertext blocks depends +on the current and all previous plaintext blocks. An Initialization Vector +(<em>IV</em>) is required.</p> +<p>The <em>IV</em> is a data block to be transmitted to the receiver. +The <em>IV</em> can be made public, but it must be authenticated by the receiver and +it should be picked randomly.</p> +<p>See <a class="rst-reference external" href="http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf" target="_top">NIST SP800-38A</a> , Section 6.2 .</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +2 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<a name="MODE_CFB"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_CFB</h3> + <p><em>Cipher FeedBack (CFB)</em>. This mode is similar to CBC, but it transforms +the underlying block cipher into a stream cipher. Plaintext and ciphertext +are processed in <em>segments</em> of <strong>s</strong> bits. The mode is therefore sometimes +labelled <strong>s</strong>-bit CFB. An Initialization Vector (<em>IV</em>) is required.</p> +<p>When encrypting, each ciphertext segment contributes to the encryption of +the next plaintext segment.</p> +<p>This <em>IV</em> is a data block to be transmitted to the receiver. +The <em>IV</em> can be made public, but it should be picked randomly. +Reusing the same <em>IV</em> for encryptions done with the same key lead to +catastrophic cryptographic failures.</p> +<p>See <a class="rst-reference external" href="http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf" target="_top">NIST SP800-38A</a> , Section 6.3 .</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +3 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<a name="MODE_OFB"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_OFB</h3> + <p><em>Output FeedBack (OFB)</em>. This mode is very similar to CBC, but it +transforms the underlying block cipher into a stream cipher. +The keystream is the iterated block encryption of an Initialization Vector (<em>IV</em>).</p> +<p>The <em>IV</em> is a data block to be transmitted to the receiver. +The <em>IV</em> can be made public, but it should be picked randomly.</p> +<p>Reusing the same <em>IV</em> for encryptions done with the same key lead to +catastrophic cryptograhic failures.</p> +<p>See <a class="rst-reference external" href="http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf" target="_top">NIST SP800-38A</a> , Section 6.4 .</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +5 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<a name="MODE_CTR"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_CTR</h3> + <p><em>CounTeR (CTR)</em>. This mode is very similar to ECB, in that +encryption of one block is done independently of all other blocks. +Unlike ECB, the block <em>position</em> contributes to the encryption and no +information leaks about symbol frequency.</p> +<p>Each message block is associated to a <em>counter</em> which must be unique +across all messages that get encrypted with the same key (not just within +the same message). The counter is as big as the block size.</p> +<p>Counters can be generated in several ways. The most straightword one is +to choose an <em>initial counter block</em> (which can be made public, similarly +to the <em>IV</em> for the other modes) and increment its lowest <strong>m</strong> bits by +one (modulo <em>2^m</em>) for each block. In most cases, <strong>m</strong> is chosen to be half +the block size.</p> +<p>Reusing the same <em>initial counter block</em> for encryptions done with the same +key lead to catastrophic cryptograhic failures.</p> +<p>See <a class="rst-reference external" href="http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf" target="_top">NIST SP800-38A</a> , Section 6.5 (for the mode) and Appendix B (for how +to manage the <em>initial counter block</em>).</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +6 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<a name="MODE_OPENPGP"></a> +<div> +<table class="details" border="1" cellpadding="3" + cellspacing="0" width="100%" bgcolor="white"> +<tr><td> + <h3 class="epydoc">MODE_OPENPGP</h3> + <p>OpenPGP. This mode is a variant of CFB, and it is only used in PGP and <a class="rst-rst-reference external rst-reference external" href="http://tools.ietf.org/html/rfc4880" target="_top">OpenPGP</a> applications. +An Initialization Vector (<em>IV</em>) is required.</p> +<p>Unlike CFB, the IV is not transmitted to the receiver. Instead, the <em>encrypted</em> IV is. +The IV is a random data block. Two of its bytes are duplicated to act as a checksum +for the correctness of the key. The encrypted IV is therefore 2 bytes longer than +the clean IV.</p> + <dl class="fields"> + </dl> + <dl class="fields"> + <dt>Value:</dt> + <dd><table><tr><td><pre class="variable"> +7 +</pre></td></tr></table> +</dd> + </dl> +</td></tr></table> +</div> +<br /> +<!-- ==================== NAVIGATION BAR ==================== --> +<table class="navbar" border="0" width="100%" cellpadding="0" + bgcolor="#a0c0ff" cellspacing="0"> + <tr valign="middle"> + <!-- Home link --> + <th> <a + href="Crypto-module.html">Home</a> </th> + + <!-- Tree link --> + <th> <a + href="module-tree.html">Trees</a> </th> + + <!-- Index link --> + <th> <a + href="identifier-index.html">Indices</a> </th> + + <!-- Help link --> + <th> <a + href="help.html">Help</a> </th> + + <!-- Project homepage --> + <th class="navbar" align="right" width="100%"> + <table border="0" cellpadding="0" cellspacing="0"> + <tr><th class="navbar" align="center" + ><a href="http://www.pycrypto.org/">PyCrypto.org</a></th> + </tr></table></th> + </tr> +</table> +<table border="0" cellpadding="0" cellspacing="0" width="100%%"> + <tr> + <td align="left" class="footer"> + Generated by Epydoc 3.0.1 on Thu May 24 09:02:36 2012 + </td> + <td align="right" class="footer"> + <a target="mainFrame" href="http://epydoc.sourceforge.net" + >http://epydoc.sourceforge.net</a> + </td> + </tr> +</table> + +<script type="text/javascript"> + <!-- + // Private objects are initially displayed (because if + // javascript is turned off then we want them to be + // visible); but by default, we want to hide them. 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