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c++crypto++onvif

Generating an ONVIF authentication digest using Crypto++?


The ONVIF authentication spec section 6.1.1.3 has what looks like a straight forward description of how to generate a digest. However, when using Crypto++ for Base64 and SHA1 operations, I cannot generate the same hash as the specification. I must be doing something wrong but cannot see what.

std::string nonce = "LKqI6G/AikKCQrN0zqZFlg==";
std::string dt = "2010-09-16T07:50:45Z";
std::string pwd = "userpassword";

{
    // result should be tuOSpGlFlIXsozq4HFNeeGeFLEI=
    // as per spec. This approach is also used here:
    // https://github.com/agsh/onvif/blob/master/lib/cam.js

    CryptoPP::Base64Decoder decoder;
    decoder.Put((byte*)nonce.data(), nonce.size());
    std::vector<uint8_t> bytes(decoder.MaxRetrievable(),0);
    decoder.Get(&bytes[0],bytes.size());

    //
    CryptoPP::SHA1 hash;
    byte digest[CryptoPP::SHA1::DIGESTSIZE];
    hash.Update(bytes.data(), bytes.size());
    hash.Update((const byte*)dt.c_str(), dt.size());
    hash.Update((const byte*)pwd.c_str(), pwd.size());
    hash.Final(digest);

    CryptoPP::Base64Encoder encoder;
    encoder.Put(digest, CryptoPP::SHA1::DIGESTSIZE);
    std::string hash64(encoder.MaxRetrievable(), 0);
    encoder.Get((byte*)hash64.data(), hash64.size());
    // generates woEIuU+ryXxcwkTZ9ktbKGeQ
    std::cout << hash64 << std::endl;
}

Any thoughts on this one much appreciated.

[edit: remove C# references]


Solution

  • CryptoPP::Base64Decoder decoder;
    decoder.Put((byte*)nonce.data(), nonce.size());
    std::vector<uint8_t> bytes(decoder.MaxRetrievable(),0);
    decoder.Get(&bytes[0],bytes.size());
    

    Call MessageEnd:

    Base64Decoder decoder;
    decoder.Put((byte*)nonce.data(), nonce.size());
    decoder.MessageEnd();
    
    vector<uint8_t> bytes(decoder.MaxRetrievable(),0);
    decoder.Get(&bytes[0],bytes.size());
    

    Ditto:

    Base64Encoder encoder;
    encoder.Put(digest, 20);
    encoder.MessageEnd();
    
    string hash64(encoder.MaxRetrievable(), 0);
    encoder.Get((byte*)hash64.data(), hash64.size());
    

    Also see Base64Encoder | Missing Data and Base64Decoder | Missing Data on the Crypto++ wiki.


    Nor indeed can I duplicate the result using any other approaches, like a full C# test bed using all of the .NET crypto resources.

    I don't know C# as well as Crypto++, so I can't help with a C# example that works as expected with ONVIF authentication.


    Here's the result I get:

    $ g++ test.cxx -I. ./libcryptopp.a -o test.exe
    $ ./test.exe 
    tuOSpGlFlIXsozq4HFNeeGeFLEI=
    

    And the cat test.cxx:

    #include <iostream>
    #include <string>
    #include <vector>
    
    #include "base64.h"
    #include "sha.h"
    
    std::string nonce = "LKqI6G/AikKCQrN0zqZFlg==";
    std::string dt = "2010-09-16T07:50:45Z";
    std::string pwd = "userpassword";
    
    int main(int argc, char* argv[])
    {
        CryptoPP::Base64Decoder decoder;
        decoder.Put((byte*)nonce.data(), nonce.size());
        decoder.MessageEnd();    
        std::vector<uint8_t> bytes(decoder.MaxRetrievable(),0);
        decoder.Get(&bytes[0],bytes.size());
    
        CryptoPP::SHA1 hash;
        byte digest[CryptoPP::SHA1::DIGESTSIZE];
        hash.Update(bytes.data(), bytes.size());
        hash.Update((const byte*)dt.c_str(), dt.size());
        hash.Update((const byte*)pwd.c_str(), pwd.size());
        hash.Final(digest);
    
        CryptoPP::Base64Encoder encoder;
        encoder.Put(digest, 20);
        encoder.MessageEnd();    
        std::string hash64(encoder.MaxRetrievable(), 0);
        encoder.Get((byte*)hash64.data(), hash64.size());
    
        std::cout << hash64 << std::endl;
    
        return 0;
    }