dcmsign: biblioteca de assinatura digital e aplicativos utilitários
Este módulo contém classes para criar assinaturas digitais em conjuntos de dados DICOM, verificá-las e removê-las. As assinaturas estão em conformidade com a extensão DICOM "Digital Signatures" (anteriormente Supplement 41). Este módulo requer a biblioteca externa OpenSSL.
As principais classes de interface são:
Ferramentas
Este módulo contém a seguinte ferramenta de linha de comando:
Exemplos
O exemplo a seguir mostra como verificar todas as assinaturas em um arquivo DICOM:
DcmFileFormat fileformat;
if (fileformat.loadFile("test.dcm").good())
{
// Load a root Certification Authority certificate from "ca_cert.pem"
// and declare it as trusted. All certificates issued by this CA will
// be considered trustworthy (if within their validity time).
SiCertificateVerifier certVerifier;
if (certVerifier.addTrustedCertificateFile("ca_cert.pem",
X509_FILETYPE_PEM).bad())
{
cerr << "unable to load CA certificate" << endl;
return;
}
// Verify all signatures in the dataset, and verify the signer
// certificate against the root CA defined above.
// Fail if no signature is present in the dataset, but do not require
// any specific DICOM signature profile. Verify a secure timestamp
// if present, but do not fail signature verification if no timestamp
// is there.
int result = DcmSignatureHelper::do_verify(fileformat.getDataset(),
certVerifier, ESVP_requireSignature, ETVP_verifyTSIfPresent);
if (result == 0)
std::cerr << "signature(s) found and successfully verified" << endl;
else
std::cerr << "signature absent or verification failed" << endl;
}
O exemplo a seguir mostra como assinar um arquivo DICOM:
DcmFileFormat fileformat;
if (fileformat.loadFile("test.dcm").good())
{
// dataset to be signed
DcmDataset *dataset = fileformat.getDataset();
// select transfer syntax in which digital signature will be created
E_TransferSyntax xfer = dataset->getOriginalXfer();
// use Little Endian Explicit for uncompressed files
if ((xfer == EXS_LittleEndianImplicit) ||
(xfer == EXS_BigEndianExplicit))
xfer = EXS_LittleEndianExplicit;
SiCreatorProfile profile; // use the "RSA Creator Profile"
SiRIPEMD160 mac; // use RIPEMD160 as MAC algorithm
SiCertificate cert; // our certificate
if (cert.loadCertificate("certificate.pem", X509_FILETYPE_PEM).bad())
{
cerr << "unable to load certificate" << endl;
return;
}
SiPrivateKey key; // private key, must be unencrypted here
if (key.loadPrivateKey("privkey.pem", X509_FILETYPE_PEM).bad())
{
cerr << "unable to load private key" << endl;
return;
}
// list of attributes to be signed. It can remain empty here
// since we're using the RSA Creator Profile to determine the
// list of attributes that needs to be signed
DcmAttributeTag tags;
// now create the signature
int result = DcmSignatureHelper::do_sign(dataset,
key, cert, &mac, &profile, &tags, xfer, NULL,
SiSignaturePurpose::ESP_none, NULL);
if (result == 0)
std::cerr << "signature successfully created" << endl;
else
std::cerr << "signature creation failed" << endl;
}