That is exactly what I needed. Thanks.
On Feb 25, 12:57 am, "Wei Dai" <[EMAIL PROTECTED]> wrote:
> Once you've got the key parts into intn and inte, just do this:
>
> CryptoPP::RSASS<CryptoPP::PSS, CryptoPP::SHA>::Verifier pub(intn, inte);
>
> or:
>
> CryptoPP::RSASS<CryptoPP::PSS, CryptoPP::SHA>::Verifier pub;
> pub.AccessKey().Initialize(intn, inte);
>
> ----- Original Message -----
> From: "BlackEye" <[EMAIL PROTECTED]>
> To: "Crypto++ Users" <[EMAIL PROTECTED]>
> Sent: Sunday, February 25, 2007 2:38 AM
> Subject: Re: Load RSA Verifier with non-encoded key parts
>
> > I had looked at the wiki before, but everything I see assumes that the
> > public key is encoded. I've tried to encode the key parts myself, but
> > I'm doing something wrong and can't figure out what it is. Here is a
> > sample piece of code that shows what I've tried.
>
> > void Base64Encode(std::string &in, std::string &out)
> > {
> > CryptoPP::StringSource(in, true, new CryptoPP::Base64Encoder(new
> > CryptoPP::StringSink(out),false));
> > }
>
> > void Base64Decode(std::string &in, std::string &out)
> > {
> > CryptoPP::StringSource(in, true, new CryptoPP::Base64Decoder(new
> > CryptoPP::StringSink(out)));
> > }
>
> > void test()
> > {
>
> > // I have base64 encoded n and e public key parts
> > std::string strb64n="AKvhKNxRU/
> > +aXwJSoOSmCjldk2YT2mVoH6w1+fprfL8qZ51ZNVPjRSCYHaKtZXgxcCENbsPbUtoV7VL0Z
> > +dGBsYtWIbQqYGZjlXPgSDNl9BvSfHpJXFVH/HTLfYWKn59E
> > +CpggHezBsscw5G9xFryqJ7MyrReMtYgGYlAwLK8n8p";
> > std::string strb64e="EQ==";
> > std::string strn;
> > std::string stre;
>
> > // decode encoded key parts
> > Base64Decode(strb64n,strn);
> > Base64Decode(strb64e,stre);
>
> > // load 2 integers with decoded key parts
> > CryptoPP::Integer intn((byte
> > *)strn.c_str(),strn.size(),CryptoPP::Integer::SIGNED);
> > CryptoPP::Integer inte((byte
> > *)stre.c_str(),stre.size(),CryptoPP::Integer::SIGNED);
>
> > std::string encodedpubstr;
> > CryptoPP::Base64Encoder encout(new
> > CryptoPP::StringSink(encodedpubstr),false);
>
> > // start DER sequence
> > CryptoPP::DERSequenceEncoder derenc(encout);
>
> > // encode n and e - tried both DEREncode and BEREncode
> > intn.DEREncode(derenc);
> > inte.DEREncode(derenc);
>
> > derenc.MessageEnd();
>
> > // output the encoded key - seems to look OK
> > std::cout << encodedpubstr << std::endl;
>
> > // now try to load this DER encoded public key into RSA verifier
> > CryptoPP::StringSource inpsource(encodedpubstr,true,new
> > CryptoPP::Base64Decoder);
> > try
> > {
> > // throws BER decode error
> > CryptoPP::RSASS<CryptoPP::PSS, CryptoPP::SHA>::Verifier
> > pub(inpsource);
> > }
> > catch( CryptoPP::Exception& e )
> > {
> > std::cerr << "Error e: " << e.what() << std::endl;
> > }
> > catch(...)
> > {
> > std::cout << "An error occurred" << std::endl;
> > }
>
> > }
>
> > On Feb 24, 11:33 am, "Jeffrey Walton" <[EMAIL PROTECTED]> wrote:
> >> Hi BlackEye,
>
> >>http://www.cryptopp.com/wiki/RSA
>
> >> Jeff
>
> >> On 2/24/07, BlackEye <[EMAIL PROTECTED]> wrote:
>
> >> > I'm trying to verify a signature (PSS encoded) on a message that was
> >> > generated with a 3rd party program. I have the n and e parts of the
> >> > RSA
> >> > public key in hex format. How can I load this non-encoded public key
> >> > into
> >> > an RSA verifier? I've tried to load up two Integers with the numbers
> >> > and
> >> > DEREncode them together, but the verifier keeps throwing a BER decode
> >> > error
> >> > when it's initialized. All the examples I have seen have assumed
> >> > some
> >> > DER/BER encoding of the key. I'm sure there is some way I can easily
> >> > do
> >> > this. Does anyone have any ideas?
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the "Crypto++ Users"
Google Group.
To unsubscribe, send an email to [EMAIL PROTECTED]
More information about Crypto++ and this group is available at
http://www.cryptopp.com.
-~----------~----~----~----~------~----~------~--~---
