<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Encrypting data.</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="Signing and encrypting documents." href="xmlsec-notes-sign-encrypt.html"> <link rel="PREVIOUS" title="Signing a document." href="xmlsec-notes-sign.html"> <link rel="NEXT" title="Creating dynamic templates." href="xmlsec-notes-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%; 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Encrypting binary data with a template.</b></p> <pre class="PROGRAMLISTING">/** * encrypt_file: * @tmpl_file: the encryption template file name. * @key_file: the Triple DES key file. * @data: the binary data to encrypt. * @dataSize: the binary data size. * * Encrypts binary #data using template from #tmpl_file and DES key from * #key_file. * * Returns 0 on success or a negative value if an error occurs. */ int encrypt_file(const char* tmpl_file, const char* key_file, const unsigned char* data, size_t dataSize) { xmlDocPtr doc = NULL; xmlNodePtr node = NULL; xmlSecEncCtxPtr encCtx = NULL; int res = -1; assert(tmpl_file); assert(key_file); assert(data); /* load template */ doc = xmlParseFile(tmpl_file); if ((doc == NULL) || (xmlDocGetRootElement(doc) == NULL)){ fprintf(stderr, "Error: unable to parse file \"%s\"\n", tmpl_file); goto done; } /* find start node */ node = xmlSecFindNode(xmlDocGetRootElement(doc), xmlSecNodeEncryptedData, xmlSecEncNs); if(node == NULL) { fprintf(stderr, "Error: start node not found in \"%s\"\n", tmpl_file); 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 */ 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(xmlSecEncCtxBinaryEncrypt(encCtx, node, data, dataSize) < 0) { fprintf(stderr,"Error: encryption failed\n"); goto done; } /* print encrypted data with document to stdout */ xmlDocDump(stdout, doc); /* success */ res = 0; done: /* cleanup */ if(encCtx != NULL) { xmlSecEncCtxDestroy(encCtx); } if(doc != NULL) { xmlFreeDoc(doc); } return(res); } </pre> <p><a href="xmlsec-encrypt-template-file.html#XMLSEC-EXAMPLE-ENCRYPT1">Full program listing</a></p> <p><a href="xmlsec-encrypt-template-file.html#XMLSEC-EXAMPLE-ENCRYPT1-TMPL">Simple encryption template file</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-sign.html"><b><<< Signing a document.</b></a></td> <td align="right"><a accesskey="n" href="xmlsec-notes-templates.html"><b>Creating dynamic templates. >>></b></a></td> </tr></table> </td></tr></table></td> </tr></table></body> </html>