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C

Canonicalize XML Fragment

See more XML Digital Signatures Examples

Demonstrates how to canonicalize a fragment of an XML document. The fragment is identified by the element having an Id attribute equal to a specified value. (The Id attribute can have any namespace, and the attribute name is case-insensitive (thus "ID", "Id", "id", etc. match).

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C
#include <C_CkHttp.h>
#include <C_CkStringBuilder.h>
#include <C_CkXmlDSig.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkHttp http;
    HCkStringBuilder sbXml;
    HCkXmlDSig canon;
    const char *canonVersion;
    BOOL withComments;
    const char *prefixList;
    const char *url;
    const char *xmlCanonFrag;

    success = FALSE;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.

    http = CkHttp_Create();
    sbXml = CkStringBuilder_Create();
    canon = CkXmlDSig_Create();

    //  Use exclusive XML canonicalization.
    canonVersion = "EXCL_C14N";
    withComments = FALSE;
    //  The optional inclusive namespaces prefix list if using exclusive canonicalization.
    prefixList = "";

    url = "https://www.chilkatsoft.com/exampleData/canonicalizeFragmentTest.xml";
    success = CkHttp_QuickGetSb(http,url,sbXml);

    //  This is the input XML:

    //  <?xml version="1.0" encoding="UTF-8"?>
    //  <Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
    //  <SignedInfo>
    //    <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" />
    //    <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1" />
    //    <Reference URI="#object">
    //      <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
    //      <DigestValue>OPnpF/ZNLDxJ/I+1F3iHhlmSwgo=</DigestValue>
    //    </Reference>
    //  </SignedInfo>
    //  <SignatureValue>nihUFQg4mDhLgecvhIcKb9Gz8VRTOlw+adiZOBBXgK4JodEe5aFfCqm8WcRIT8GL
    //  LXSk8PsUP4//SsKqUBQkpotcAqQAhtz2v9kCWdoUDnAOtFZkd/CnsZ1sge0ndha4
    //  0wWDV+nOWyJxkYgicvB8POYtSmldLLepPGMz+J7/Uws=</SignatureValue>
    //  <KeyInfo>
    //    <KeyValue>
    //      <RSAKeyValue>
    //        <Modulus>4IlzOY3Y9fXoh3Y5f06wBbtTg94Pt6vcfcd1KQ0FLm0S36aGJtTSb6pYKfyX7PqC
    //        UQ8wgL6xUJ5GRPEsu9gyz8ZobwfZsGCsvu40CWoT9fcFBZPfXro1Vtlh/xl/yYHm
    //        +Gzqh0Bw76xtLHSfLfpVOrmZdwKmSFKMTvNXOFd0V18=</Modulus>
    //        <Exponent>AQAB</Exponent>
    //      </RSAKeyValue>
    //    </KeyValue>
    //  </KeyInfo>
    //  <Object Id="object">some text
    //    with spaces and CR-LF.</Object>
    //  </Signature>

    //  Canonicalize and return the fragment of XML starting at the element where the Id attribute equals "object".
    xmlCanonFrag = CkXmlDSig_canonicalizeFragment(canon,CkStringBuilder_getAsString(sbXml),"object",canonVersion,prefixList,withComments);
    printf("%s\n",xmlCanonFrag);

    //  The output is:
    //  
    //  <Object xmlns="http://www.w3.org/2000/09/xmldsig#" Id="object">some text
    //    with spaces and CR-LF.</Object>
    //  


    CkHttp_Dispose(http);
    CkStringBuilder_Dispose(sbXml);
    CkXmlDSig_Dispose(canon);

    }