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diff --git a/docs/api/src/chapters/creating-templates.sgml b/docs/api/src/chapters/creating-templates.sgml new file mode 100644 index 00000000..4d6088f3 --- /dev/null +++ b/docs/api/src/chapters/creating-templates.sgml @@ -0,0 +1,325 @@ +<chapter id="xmlsec-notes-templates"> + <title>Creating dynamic templates.</title> + <sect1 id="xmlsec-notes-templates-overview"> + <title>Overview.</title> + <para>The XML Security Library uses templates to describe + how and what data should be signed or encrypted. The template + is a regular XML file. You can create templates in advance + using your favorite XML files editor, load them from a file + and use for creating signature or encrypting data. You can + also create templates dynamicaly. The XML Security Library + provides helper functions to quickly create dynamic templates + inside your application.</para> + </sect1> + <sect1 id="xmlsec-notes-dynamic-signature-templates"> + <title>Creating dynamic signature templates.</title> + <para>The signature template has structure similar + to the XML Digital Signature structure as it is described in + <ulink URL="http://www.w3.org/TR/xmldsig-core">specification</ulink>. + 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. + </para> + <figure> + <title>XML Digital Signature structure</title> + <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> + </programlisting> + </figure> + <para> + <example> + <title>Creating dynamic signature template.</title> + <programlisting><![CDATA[ +/** + * 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); +} + ]]></programlisting> + <simpara><link linkend="xmlsec-example-sign2">Full program listing</link></simpara> + </example> + </para> + </sect1> + + <sect1 id="xmlsec-notes-dynamic-encryption-templates"> + <title>Creating dynamic encryption templates.</title> + <para>The encryption template has structure similar + to the XML Encryption structure as it is described in + <ulink URL="http://www.w3.org/TR/xmlenc-core">specification</ulink>. + The only difference is that some nodes (for example, + <enc:CipherValue/>) + are empty. The XML Security Library sets the content of these + nodes after doing necessary calculations. + </para> + <figure> + <title>XML Encryption structure</title> + <programlisting> +<enc:EncryptedData Id? Type? MimeType? Encoding?> + <enc:EncryptionMethod Algorithm />? + (<dsig:KeyInfo> + <dsig:KeyName>? + <dsig:KeyValue>? + <dsig:RetrievalMethod>? + <dsig:X509Data>? + <dsig:PGPData>? + <enc:EncryptedKey>? + <enc:AgreementMethod>? + <dsig:KeyName>? + <dsig:RetrievalMethod>? + <*>? + </dsig:KeyInfo>)? + <enc:CipherData> + <enc:CipherValue>? + <enc:CipherReference URI?>? + </enc:CipherData> + <enc:EncryptionProperties>? +</enc:EncryptedData> + </programlisting> + </figure> + <para> + <example> + <title>Creating dynamic encrytion template.</title> + <programlisting><![CDATA[ +/** + * encrypt_file: + * @xml_file: the encryption template file name. + * @key_file: the Triple DES key file. + * + * Encrypts #xml_file using a dynamicaly created template and DES key from + * #key_file. + * + * Returns 0 on success or a negative value if an error occurs. + */ +int +encrypt_file(const char* xml_file, const char* key_file) { + xmlDocPtr doc = NULL; + xmlNodePtr encDataNode = NULL; + xmlNodePtr keyInfoNode = NULL; + xmlSecEncCtxPtr encCtx = NULL; + int res = -1; + + assert(xml_file); + assert(key_file); + + /* load template */ + doc = xmlParseFile(xml_file); + if ((doc == NULL) || (xmlDocGetRootElement(doc) == NULL)){ + fprintf(stderr, "Error: unable to parse file \"%s\"\n", xml_file); + goto done; + } + + /* create encryption template to encrypt XML file and replace + * its content with encryption result */ + encDataNode = xmlSecTmplEncDataCreate(doc, xmlSecTransformDes3CbcId, + NULL, xmlSecTypeEncElement, NULL, NULL); + if(encDataNode == NULL) { + fprintf(stderr, "Error: failed to create encryption template\n"); + goto done; + } + + /* we want to put encrypted data in the <enc:CipherValue/> node */ + if(xmlSecTmplEncDataEnsureCipherValue(encDataNode) == NULL) { + fprintf(stderr, "Error: failed to add CipherValue node\n"); + goto done; + } + + /* add <dsig:KeyInfo/> and <dsig:KeyName/> nodes to put key name in the signed document */ + keyInfoNode = xmlSecTmplEncDataEnsureKeyInfo(encDataNode, 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 encryption context, we don't need keys manager in this example */ + encCtx = xmlSecEncCtxCreate(NULL); + if(encCtx == NULL) { + fprintf(stderr,"Error: failed to create encryption context\n"); + goto done; + } + + /* load DES key, assuming that there is not password */ + encCtx->encKey = xmlSecKeyReadBinaryFile(xmlSecKeyDataDesId, key_file); + if(encCtx->encKey == NULL) { + fprintf(stderr,"Error: failed to load des key from binary file \"%s\"\n", key_file); + goto done; + } + + /* set key name to the file name, this is just an example! */ + if(xmlSecKeySetName(encCtx->encKey, key_file) < 0) { + fprintf(stderr,"Error: failed to set key name for key from \"%s\"\n", key_file); + goto done; + } + + /* encrypt the data */ + if(xmlSecEncCtxXmlEncrypt(encCtx, encDataNode, xmlDocGetRootElement(doc)) < 0) { + fprintf(stderr,"Error: encryption failed\n"); + goto done; + } + + /* we template is inserted in the doc */ + encDataNode = NULL; + + /* print encrypted data with document to stdout */ + xmlDocDump(stdout, doc); + + /* success */ + res = 0; + +done: + + /* cleanup */ + if(encCtx != NULL) { + xmlSecEncCtxDestroy(encCtx); + } + + if(encDataNode != NULL) { + xmlFreeNode(encDataNode); + } + + if(doc != NULL) { + xmlFreeDoc(doc); + } + return(res); +} + ]]></programlisting> + <simpara><link linkend="xmlsec-example-encrypt2">Full program listing</link></simpara> + </example> + </para> + </sect1> +</chapter> |