<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Creating dynamic signature templates.</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="Creating dynamic templates." href="xmlsec-notes-templates.html">
<link rel="PREVIOUS" title="Creating dynamic templates." href="xmlsec-notes-templates.html">
<link rel="NEXT" title="Creating dynamic encryption templates." href="xmlsec-notes-dynamic-encryption-templates.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-templates.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td>
<td><a accesskey="u" href="xmlsec-notes-templates.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-dynamic-encryption-templates.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td>
</tr></table>
<br clear="all"><div class="SECT1">
<h1 class="SECT1"><a name="XMLSEC-NOTES-DYNAMIC-SIGNATURE-TEMPLATES">Creating dynamic signature templates.</a></h1>
<p>The signature template has structure similar
to the XML Digital Signature structure as it is described in
<a href="http://www.w3.org/TR/xmldsig-core" target="_top">specification</a>.
The only difference is that some nodes (for example,
<dsig:DigestValue/> or <SignatureValue/>)
are empty. The XML Security Library sets the content of these
nodes after doing necessary calculations.
</p>
<div class="FIGURE">
<a name="AEN243"></a><p><b>Figure 1. XML Digital Signature structure</b></p>
<pre class="PROGRAMLISTING"><dsig:Signature ID?>
<dsig:SignedInfo>
<dsig:CanonicalizationMethod Algorithm />
<dsig:SignatureMethod Algorithm />
(<dsig:Reference URI? >
(<dsig:Transforms>
(<dsig:Transform Algorithm />)+
</dsig:Transforms>)?
<dsig:DigestMethod Algorithm >
<dsig:DigestValue>
</dsig:Reference>)+
</dsig:SignedInfo>
<dsig:SignatureValue>
(<dsig:KeyInfo>
<dsig:KeyName>?
<dsig:KeyValue>?
<dsig:RetrievalMethod>?
<dsig:X509Data>?
<dsig:PGPData>?
<enc:EncryptedKey>?
<enc:AgreementMethod>?
<dsig:KeyName>?
<dsig:RetrievalMethod>?
<*>?
</dsig:KeyInfo>)?
(<dsig:Object ID?>)*
</dsig:Signature>
</pre>
</div>
<p> </p>
<div class="EXAMPLE">
<a name="AEN247"></a><p><b>Example 1. Creating dynamic signature template.</b></p>
<pre class="PROGRAMLISTING">/**
* sign_file:
* @xml_file: the XML file name.
* @key_file: the PEM private key file name.
*
* Signs the #xml_file using private key from #key_file and dynamicaly
* created enveloped signature template.
*
* Returns 0 on success or a negative value if an error occurs.
*/
int
sign_file(const char* xml_file, const char* key_file) {
xmlDocPtr doc = NULL;
xmlNodePtr signNode = NULL;
xmlNodePtr refNode = NULL;
xmlNodePtr keyInfoNode = NULL;
xmlSecDSigCtxPtr dsigCtx = NULL;
int res = -1;
assert(xml_file);
assert(key_file);
/* load doc file */
doc = xmlParseFile(xml_file);
if ((doc == NULL) || (xmlDocGetRootElement(doc) == NULL)){
fprintf(stderr, "Error: unable to parse file \"%s\"\n", xml_file);
goto done;
}
/* create signature template for RSA-SHA1 enveloped signature */
signNode = xmlSecTmplSignatureCreate(doc, xmlSecTransformExclC14NId,
xmlSecTransformRsaSha1Id, NULL);
if(signNode == NULL) {
fprintf(stderr, "Error: failed to create signature template\n");
goto done;
}
/* add <dsig:Signature/> node to the doc */
xmlAddChild(xmlDocGetRootElement(doc), signNode);
/* add reference */
refNode = xmlSecTmplSignatureAddReference(signNode, xmlSecTransformSha1Id,
NULL, NULL, NULL);
if(refNode == NULL) {
fprintf(stderr, "Error: failed to add reference to signature template\n");
goto done;
}
/* add enveloped transform */
if(xmlSecTmplReferenceAddTransform(refNode, xmlSecTransformEnvelopedId) == NULL) {
fprintf(stderr, "Error: failed to add enveloped transform to reference\n");
goto done;
}
/* add <dsig:KeyInfo/> and <dsig:KeyName/> nodes to put key name in the signed document */
keyInfoNode = xmlSecTmplSignatureEnsureKeyInfo(signNode, NULL);
if(keyInfoNode == NULL) {
fprintf(stderr, "Error: failed to add key info\n");
goto done;
}
if(xmlSecTmplKeyInfoAddKeyName(keyInfoNode, NULL) == NULL) {
fprintf(stderr, "Error: failed to add key name\n");
goto done;
}
/* create signature context, we don't need keys manager in this example */
dsigCtx = xmlSecDSigCtxCreate(NULL);
if(dsigCtx == NULL) {
fprintf(stderr,"Error: failed to create signature context\n");
goto done;
}
/* load private key, assuming that there is not password */
dsigCtx->signKey = xmlSecCryptoAppKeyLoad(key_file, xmlSecKeyDataFormatPem, NULL, NULL, NULL);
if(dsigCtx->signKey == NULL) {
fprintf(stderr,"Error: failed to load private pem key from \"%s\"\n", key_file);
goto done;
}
/* set key name to the file name, this is just an example! */
if(xmlSecKeySetName(dsigCtx->signKey, key_file) < 0) {
fprintf(stderr,"Error: failed to set key name for key from \"%s\"\n", key_file);
goto done;
}
/* sign the template */
if(xmlSecDSigCtxSign(dsigCtx, signNode) < 0) {
fprintf(stderr,"Error: signature failed\n");
goto done;
}
/* print signed document to stdout */
xmlDocDump(stdout, doc);
/* success */
res = 0;
done:
/* cleanup */
if(dsigCtx != NULL) {
xmlSecDSigCtxDestroy(dsigCtx);
}
if(doc != NULL) {
xmlFreeDoc(doc);
}
return(res);
}
</pre>
<p><a href="xmlsec-examples-sign-dynamimc-template.html#XMLSEC-EXAMPLE-SIGN2">Full program listing</a></p>
</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-templates.html"><b><<< Creating dynamic templates.</b></a></td>
<td align="right"><a accesskey="n" href="xmlsec-notes-dynamic-encryption-templates.html"><b>Creating dynamic encryption templates. >>></b></a></td>
</tr></table>
</td></tr></table></td>
</tr></table></body>
</html>
