Re: [c++] RE: CounterSignature or Multiple Signatures - is it possible?

[John Moore]

Berin,

I am still new at programming with this stuff (actually I am a manager type who 
only programs a bit to keep my hand in). I have been extending the toy program 
that I was working on and have found a more elegant solution to the problem of 
how to check multiple DSIGs. I have found a standard Xerces method that will 
search the DOM tree and return Named Nodes. So the whole routine that I sent to 
you is not really needed. The following code snippet shows how to check 
multiple DSIGs using the Xerces routine (instead of my routine). Again the 
variable "result" is true if all DSIGs verify and the variable "sigcnt" 
contains the index of the last DSIG that verified correctly. 

Ta John


        //Solution #2 (using Xerces methods)
        DomList = theDOM->getElementsByTagNameNS
(DSIGConstants::s_unicodeStrURIDSIG, MAKE_UNICODE_STRING("Signature"));
        sigNode = DomList->item(0);

        sigcnt = 0;
        result = true;

        while ((result) && (sigNode != NULL)) {

                sig = prov.newSignatureFromDOM(theDOM, sigNode);

                // use your favourite Resolver 
                xxxKeyResolver ires(NULL);
                sig->setKeyInfoResolver(&ires);

                try {
                        sig->load();
                        result = sig->verify();
                }

                catch (XSECException &e) {
                        char * msg = XMLString::transcode(e.getMsg());
                        cerr << "An error occured during signature 
verification"n   Message: "
                        << msg << endl;
                        XMLString::release(msg);
                        result = false;
                }
                catch (XSECCryptoException &e) {
                        cerr << "An error occured during signature 
verification"n   Message: "
                        << e.getMsg() << endl;
                        ERR_load_crypto_strings();
                        BIO * bio_err;
                        if ((bio_err=BIO_new(BIO_s_file())) != NULL)
                                BIO_set_fp
(bio_err,stderr,BIO_NOCLOSE|BIO_FP_TEXT);

                        ERR_print_errors(bio_err);
                        result = false;
                }

                sigcnt += 1;
                sigNode = DomList->item(sigcnt);
        }