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diff --git a/docs/api/xmlsec-notes-transforms.html b/docs/api/xmlsec-notes-transforms.html new file mode 100644 index 00000000..3bda65e1 --- /dev/null +++ b/docs/api/xmlsec-notes-transforms.html @@ -0,0 +1,154 @@ +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>Transforms and transforms chain.</title> +<meta name="GENERATOR" content="Modular DocBook HTML Stylesheet Version 1.79"> +<link rel="HOME" title="XML Security Library Reference Manual" href="index.html"> +<link rel="UP" title="XML Security Library Tutorial" href="xmlsec-notes.html"> +<link rel="PREVIOUS" title="Verifing document signed with X509 certificates." href="xmlsec-notes-verify-x509.html"> +<link rel="NEXT" title="Using context objects." href="xmlsec-notes-contexts.html"> +<style type="text/css">.synopsis, .classsynopsis { + background: #eeeeee; + border: solid 1px #aaaaaa; + padding: 0.5em; +} +.programlisting { + background: #eeeeff; + border: solid 1px #aaaaff; + padding: 0.5em; +} +.variablelist { + padding: 4px; + margin-left: 3em; +} +.navigation { + background: #ffeeee; + border: solid 1px #ffaaaa; + margin-top: 0.5em; + margin-bottom: 0.5em; +} +.navigation a { + color: #770000; +} +.navigation a:visited { + color: #550000; +} +.navigation .title { + font-size: 200%; +}</style> +</head> +<body><table witdh="100%" valign="top"><tr valign="top"> +<td valign="top" align="left" width="210"> +<img src="../images/logo.gif" alt="XML Security Library" border="0"><p></p> +<ul> +<li><a href="../index.html">Home</a></li> +<li><a href="../download.html">Download</a></li> +<li><a href="../news.html">News</a></li> +<li><a href="../documentation.html">Documentation</a></li> +<ul> +<li><a href="../faq.html">FAQ</a></li> +<li><a href="../api/xmlsec-notes.html">Tutorial</a></li> +<li><a href="../api/xmlsec-reference.html">API reference</a></li> +<li><a href="../api/xmlsec-examples.html">Examples</a></li> +</ul> +<li><a href="../xmldsig.html">XML Digital Signature</a></li> +<ul><li><a href="http://www.aleksey.com/xmlsec/xmldsig-verifier.html">Online Verifier</a></li></ul> +<li><a href="../xmlenc.html">XML Encryption</a></li> +<li><a href="../c14n.html">XML Canonicalization</a></li> +<li><a href="../bugs.html">Reporting Bugs</a></li> +<li><a href="http://www.aleksey.com/pipermail/xmlsec">Mailing list</a></li> +<li><a href="../related.html">Related</a></li> +<li><a href="../authors.html">Authors</a></li> +</ul> +<table width="100%"> +<tr> +<td width="15"></td> +<td><a href="http://xmlsoft.org/"><img src="../images/libxml2-logo.png" alt="LibXML2" border="0"></a></td> +</tr> +<tr> +<td width="15"></td> +<td><a href="http://xmlsoft.org/XSLT"><img src="../images/libxslt-logo.png" alt="LibXSLT" border="0"></a></td> +</tr> +<tr> +<td width="15"></td> +<td><a href="http://www.openssl.org/"><img src="../images/openssl-logo.png" alt="OpenSSL" border="0"></a></td> +</tr> +<!--Links - start--><!--Links - end--> +</table> +</td> +<td valign="top"><table width="100%" valign="top"><tr><td valign="top" align="left" id="xmlsecContent"> +<table width="100%" class="navigation" summary="Navigation header" cellpadding="2" cellspacing="2"><tr valign="middle"> +<td><a accesskey="p" href="xmlsec-notes-verify-x509.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td> +<td><a accesskey="u" href="xmlsec-notes.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td> +<td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td> +<th width="100%" align="center">XML Security Library Reference Manual</th> +<td><a accesskey="n" href="xmlsec-notes-contexts.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td> +</tr></table> +<div class="CHAPTER"> +<h1> +<a name="XMLSEC-NOTES-TRANSFORMS"></a>Transforms and transforms chain.</h1> +<p>XML Digital Signature and XML Encryption standards are + very flexible and provide an XML developer many different ways to + sign or encrypt any part (or even parts) of an XML document. + The key for such great flexibility is the "transforms" model. + Transform is defined as a method of pre-processing binary or XML data + before calculating digest or signature. XML Security Library extends + this definition and names "transform" any operation performed on + the data: reading data from an URI, xml parsing, xml transformation, + calculation digest, encrypting or decrypting. Each XML Security Library + transform provides at least one of the following callbacks: + </p> +<p></p> +<ul> +<li><p> <a href="xmlsec-transforms.html#XMLSECTRANSFORMPUSHBINMETHOD">push binary data</a>; + </p></li> +<li><p> <a href="xmlsec-transforms.html#XMLSECTRANSFORMPUSHXMLMETHOD">push xml data</a>; + </p></li> +<li><p> <a href="xmlsec-transforms.html#XMLSECTRANSFORMPOPBINMETHOD">pop binary data</a>; + </p></li> +<li><p> <a href="xmlsec-transforms.html#XMLSECTRANSFORMPOPXMLMETHOD">pop xml data</a>. + </p></li> +</ul> +<p>One additional <a href="xmlsec-transforms.html#XMLSECTRANSFORMEXECUTEMETHOD">execute</a> + callback was added to simplify the development and reduce code size. + This callback is used by default + implementations of the four external callbacks from the list above. + For example, most of the crypto transforms could be implemented by + just implementing one "execute" callback and using default push/pop + binary data callbacks. However, in some cases using push/pop callbacks + directly is more efficient. + </p> +<div class="FIGURE"> +<a name="AEN470"></a><p><b>Figure 1. The XML Security Library transform.</b></p> +<p><img src="images/transform.png" align="CENTER"></p> +</div> +<p>XML Security Library constructs transforms chain according to the + signature/encryption template or signed/encrypted document. + If necessary, XML Security Library inserts XML parser or defaul + canonicalization to ensure that the output data type (binary or XML) + of previous transform matches the input of the next transform. + </p> +<p>The data are processed by pushing through or poping from the chain + depending on the transforms in the chain. For example, then binary + data chunk is pushed through a binary-to-binary transform, it + processes this chunk and pushes the result to the next transform + in the chain. + </p> +<div class="FIGURE"> +<a name="AEN475"></a><p><b>Figure 2. Transforms chain created for <dsig:Reference/> element processing.</b></p> +<p><img src="images/transforms-chain.png" align="CENTER"></p> +</div> +<p> </p> +<div class="EXAMPLE"> +<a name="AEN479"></a><p><b>Example 1. Walking through transforms chain.</b></p> +<pre class="PROGRAMLISTING">TODO + </pre> +</div> + </div> +<table class="navigation" width="100%" summary="Navigation footer" cellpadding="2" cellspacing="2"><tr valign="middle"> +<td align="left"><a accesskey="p" href="xmlsec-notes-verify-x509.html"><b><<< Verifing document signed with X509 certificates.</b></a></td> +<td align="right"><a accesskey="n" href="xmlsec-notes-contexts.html"><b>Using context objects. >>></b></a></td> +</tr></table> +</td></tr></table></td> +</tr></table></body> +</html> |