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Diffstat (limited to 'examples/encrypt3.c')
-rw-r--r-- | examples/encrypt3.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/examples/encrypt3.c b/examples/encrypt3.c new file mode 100644 index 00000000..aa9465a2 --- /dev/null +++ b/examples/encrypt3.c @@ -0,0 +1,340 @@ +/** + * XML Security Library example: Encrypting XML file with a session key and dynamicaly created template. + * + * Encrypts XML file using a dynamicaly created template file and a session + * DES key (encrypted with an RSA key). + * + * Usage: + * ./encrypt3 <xml-doc> <rsa-pem-key-file> + * + * Example: + * ./encrypt3 encrypt3-doc.xml rsakey.pem > encrypt3-res.xml + * + * The result could be decrypted with decrypt3 example: + * ./decrypt3 encrypt3-res.xml + * + * This is free software; see Copyright file in the source + * distribution for preciese wording. + * + * Copyright (C) 2002-2003 Aleksey Sanin <aleksey@aleksey.com> + */ +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +#include <libxml/tree.h> +#include <libxml/xmlmemory.h> +#include <libxml/parser.h> + +#ifndef XMLSEC_NO_XSLT +#include <libxslt/xslt.h> +#include <libxslt/security.h> +#endif /* XMLSEC_NO_XSLT */ + +#include <xmlsec/xmlsec.h> +#include <xmlsec/xmltree.h> +#include <xmlsec/xmlenc.h> +#include <xmlsec/templates.h> +#include <xmlsec/crypto.h> + +xmlSecKeysMngrPtr load_rsa_keys(char* key_file); +int encrypt_file(xmlSecKeysMngrPtr mngr, const char* xml_file, const char* key_name); + +int +main(int argc, char **argv) { + xmlSecKeysMngrPtr mngr; +#ifndef XMLSEC_NO_XSLT + xsltSecurityPrefsPtr xsltSecPrefs = NULL; +#endif /* XMLSEC_NO_XSLT */ + + assert(argv); + + if(argc != 3) { + fprintf(stderr, "Error: wrong number of arguments.\n"); + fprintf(stderr, "Usage: %s <xml-file> <key-file>\n", argv[0]); + return(1); + } + + /* Init libxml and libxslt libraries */ + xmlInitParser(); + LIBXML_TEST_VERSION + xmlLoadExtDtdDefaultValue = XML_DETECT_IDS | XML_COMPLETE_ATTRS; + xmlSubstituteEntitiesDefault(1); +#ifndef XMLSEC_NO_XSLT + xmlIndentTreeOutput = 1; +#endif /* XMLSEC_NO_XSLT */ + + /* Init libxslt */ +#ifndef XMLSEC_NO_XSLT + /* disable everything */ + xsltSecPrefs = xsltNewSecurityPrefs(); + xsltSetSecurityPrefs(xsltSecPrefs, XSLT_SECPREF_READ_FILE, xsltSecurityForbid); + xsltSetSecurityPrefs(xsltSecPrefs, XSLT_SECPREF_WRITE_FILE, xsltSecurityForbid); + xsltSetSecurityPrefs(xsltSecPrefs, XSLT_SECPREF_CREATE_DIRECTORY, xsltSecurityForbid); + xsltSetSecurityPrefs(xsltSecPrefs, XSLT_SECPREF_READ_NETWORK, xsltSecurityForbid); + xsltSetSecurityPrefs(xsltSecPrefs, XSLT_SECPREF_WRITE_NETWORK, xsltSecurityForbid); + xsltSetDefaultSecurityPrefs(xsltSecPrefs); +#endif /* XMLSEC_NO_XSLT */ + + /* Init xmlsec library */ + if(xmlSecInit() < 0) { + fprintf(stderr, "Error: xmlsec initialization failed.\n"); + return(-1); + } + + /* Check loaded library version */ + if(xmlSecCheckVersion() != 1) { + fprintf(stderr, "Error: loaded xmlsec library version is not compatible.\n"); + return(-1); + } + + /* Load default crypto engine if we are supporting dynamic + * loading for xmlsec-crypto libraries. Use the crypto library + * name ("openssl", "nss", etc.) to load corresponding + * xmlsec-crypto library. + */ +#ifdef XMLSEC_CRYPTO_DYNAMIC_LOADING + if(xmlSecCryptoDLLoadLibrary(BAD_CAST XMLSEC_CRYPTO) < 0) { + fprintf(stderr, "Error: unable to load default xmlsec-crypto library. Make sure\n" + "that you have it installed and check shared libraries path\n" + "(LD_LIBRARY_PATH) envornment variable.\n"); + return(-1); + } +#endif /* XMLSEC_CRYPTO_DYNAMIC_LOADING */ + + /* Init crypto library */ + if(xmlSecCryptoAppInit(NULL) < 0) { + fprintf(stderr, "Error: crypto initialization failed.\n"); + return(-1); + } + + /* Init xmlsec-crypto library */ + if(xmlSecCryptoInit() < 0) { + fprintf(stderr, "Error: xmlsec-crypto initialization failed.\n"); + return(-1); + } + + /* create keys manager and load keys */ + mngr = load_rsa_keys(argv[2]); + if(mngr == NULL) { + return(-1); + } + + /* we use key filename as key name here */ + if(encrypt_file(mngr, argv[1], argv[2]) < 0) { + xmlSecKeysMngrDestroy(mngr); + return(-1); + } + + /* destroy keys manager */ + xmlSecKeysMngrDestroy(mngr); + + /* Shutdown xmlsec-crypto library */ + xmlSecCryptoShutdown(); + + /* Shutdown crypto library */ + xmlSecCryptoAppShutdown(); + + /* Shutdown xmlsec library */ + xmlSecShutdown(); + + /* Shutdown libxslt/libxml */ +#ifndef XMLSEC_NO_XSLT + xsltFreeSecurityPrefs(xsltSecPrefs); + xsltCleanupGlobals(); +#endif /* XMLSEC_NO_XSLT */ + xmlCleanupParser(); + + return(0); +} + +/** + * load_rsa_keys: + * @key_file: the key filename. + * + * Creates simple keys manager and load RSA key from #key_file in it. + * The caller is responsible for destroing returned keys manager using + * @xmlSecKeysMngrDestroy. + * + * Returns the pointer to newly created keys manager or NULL if an error + * occurs. + */ +xmlSecKeysMngrPtr +load_rsa_keys(char* key_file) { + xmlSecKeysMngrPtr mngr; + xmlSecKeyPtr key; + + assert(key_file); + + /* create and initialize keys manager, we use a simple list based + * keys manager, implement your own xmlSecKeysStore klass if you need + * something more sophisticated + */ + mngr = xmlSecKeysMngrCreate(); + if(mngr == NULL) { + fprintf(stderr, "Error: failed to create keys manager.\n"); + return(NULL); + } + if(xmlSecCryptoAppDefaultKeysMngrInit(mngr) < 0) { + fprintf(stderr, "Error: failed to initialize keys manager.\n"); + xmlSecKeysMngrDestroy(mngr); + return(NULL); + } + + /* load private RSA key */ + key = xmlSecCryptoAppKeyLoad(key_file, xmlSecKeyDataFormatPem, NULL, NULL, NULL); + if(key == NULL) { + fprintf(stderr,"Error: failed to load rsa key from file \"%s\"\n", key_file); + xmlSecKeysMngrDestroy(mngr); + return(NULL); + } + + /* set key name to the file name, this is just an example! */ + if(xmlSecKeySetName(key, BAD_CAST key_file) < 0) { + fprintf(stderr,"Error: failed to set key name for key from \"%s\"\n", key_file); + xmlSecKeyDestroy(key); + xmlSecKeysMngrDestroy(mngr); + return(NULL); + } + + /* add key to keys manager, from now on keys manager is responsible + * for destroying key + */ + if(xmlSecCryptoAppDefaultKeysMngrAdoptKey(mngr, key) < 0) { + fprintf(stderr,"Error: failed to add key from \"%s\" to keys manager\n", key_file); + xmlSecKeyDestroy(key); + xmlSecKeysMngrDestroy(mngr); + return(NULL); + } + + return(mngr); +} + +/** + * encrypt_file: + * @mngr: the pointer to keys manager. + * @xml_file: the encryption template file name. + * @key_name: the RSA key name. + * + * Encrypts #xml_file using a dynamicaly created template, a session DES key + * and an RSA key from keys manager. + * + * Returns 0 on success or a negative value if an error occurs. + */ +int +encrypt_file(xmlSecKeysMngrPtr mngr, const char* xml_file, const char* key_name) { + xmlDocPtr doc = NULL; + xmlNodePtr encDataNode = NULL; + xmlNodePtr keyInfoNode = NULL; + xmlNodePtr encKeyNode = NULL; + xmlNodePtr keyInfoNode2 = NULL; + xmlSecEncCtxPtr encCtx = NULL; + int res = -1; + + assert(mngr); + assert(xml_file); + assert(key_name); + + /* 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/> */ + keyInfoNode = xmlSecTmplEncDataEnsureKeyInfo(encDataNode, NULL); + if(keyInfoNode == NULL) { + fprintf(stderr, "Error: failed to add key info\n"); + goto done; + } + + /* add <enc:EncryptedKey/> to store the encrypted session key */ + encKeyNode = xmlSecTmplKeyInfoAddEncryptedKey(keyInfoNode, + xmlSecTransformRsaPkcs1Id, + NULL, NULL, NULL); + if(encKeyNode == NULL) { + fprintf(stderr, "Error: failed to add key info\n"); + goto done; + } + + /* we want to put encrypted key in the <enc:CipherValue/> node */ + if(xmlSecTmplEncDataEnsureCipherValue(encKeyNode) == NULL) { + fprintf(stderr, "Error: failed to add CipherValue node\n"); + goto done; + } + + /* add <dsig:KeyInfo/> and <dsig:KeyName/> nodes to <enc:EncryptedKey/> */ + keyInfoNode2 = xmlSecTmplEncDataEnsureKeyInfo(encKeyNode, NULL); + if(keyInfoNode2 == NULL) { + fprintf(stderr, "Error: failed to add key info\n"); + goto done; + } + + /* set key name so we can lookup key when needed */ + if(xmlSecTmplKeyInfoAddKeyName(keyInfoNode2, key_name) == NULL) { + fprintf(stderr, "Error: failed to add key name\n"); + goto done; + } + + /* create encryption context */ + encCtx = xmlSecEncCtxCreate(mngr); + if(encCtx == NULL) { + fprintf(stderr,"Error: failed to create encryption context\n"); + goto done; + } + + /* generate a Triple DES key */ + encCtx->encKey = xmlSecKeyGenerate(xmlSecKeyDataDesId, 192, xmlSecKeyDataTypeSession); + if(encCtx->encKey == NULL) { + fprintf(stderr,"Error: failed to generate session des key\n"); + 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); +} + |