/* Decrypt an encrypted DSA private key. Then use that key to sign a message. Written by Jack Lloyd (lloyd@randombit.net), August 5, 2002 Updated to use X.509 and PKCS #8 format keys, October 21, 2002 This file is in the public domain */ #include #include #include #include #include #include #include #include using namespace Botan; const std::string SUFFIX = ".sig"; int main(int argc, char* argv[]) { if(argc != 4) { std::cout << "Usage: " << argv[0] << " keyfile messagefile passphrase" << std::endl; return 1; } Botan::LibraryInitializer init; try { std::string passphrase(argv[3]); std::ifstream message(argv[2]); if(!message) { std::cout << "Couldn't read the message file." << std::endl; return 1; } std::string outfile = argv[2] + SUFFIX; std::ofstream sigfile(outfile.c_str()); if(!sigfile) { std::cout << "Couldn't write the signature to " << outfile << std::endl; return 1; } AutoSeeded_RNG rng; std::auto_ptr key( PKCS8::load_key(argv[1], rng, passphrase) ); DSA_PrivateKey* dsakey = dynamic_cast(key.get()); if(!dsakey) { std::cout << "The loaded key is not a DSA key!\n"; return 1; } PK_Signer signer(*dsakey, get_emsa("EMSA1(SHA-1)")); DataSource_Stream in(message); byte buf[4096] = { 0 }; while(u32bit got = in.read(buf, sizeof(buf))) signer.update(buf, got); Pipe pipe(new Base64_Encoder); pipe.process_msg(signer.signature(rng)); sigfile << pipe.read_all_as_string() << std::endl; } catch(std::exception& e) { std::cout << "Exception caught: " << e.what() << std::endl; } return 0; }