Support to sign a document with a specified signature

Change-Id: I92e392b315c9217b63db830dea1b2e91387b56c2
Reviewed-on: https://gerrit.libreoffice.org/61778
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

offapi/com/sun/star/security/XDocumentDigitalSignatures.idl

@@ -191,7 +191,15 @@ interface XDocumentDigitalSignatures : com::sun::star::uno::XInterface
      */
     com::sun::star::security::XCertificate chooseCertificateWithProps( [out] sequence<::com::sun::star::beans::PropertyValue> Properties);
 
-} ;
+    /** Signs the content of the document with the provided certificate.
+
+        @since LibreOffice 6.2
+     */
+    boolean signDocumentWithCertificate([in] ::com::sun::star::security::XCertificate xCertificate,
+                                        [in] ::com::sun::star::embed::XStorage xStorage,
+                                        [in] ::com::sun::star::io::XStream xStream);
+
+};
 
 } ; } ; } ; } ;
 

xmlsecurity/source/component/documentdigitalsignatures.cxx

@@ -168,6 +168,11 @@ public:
         SAL_CALL chooseEncryptionCertificate() override;
     css::uno::Reference<css::security::XCertificate> SAL_CALL chooseCertificateWithProps(
         css::uno::Sequence<::com::sun::star::beans::PropertyValue>& Properties) override;
+
+    sal_Bool SAL_CALL signDocumentWithCertificate(
+                            css::uno::Reference<css::security::XCertificate> const & xCertificate,
+                            css::uno::Reference<css::embed::XStorage> const & xStoragexStorage,
+                            css::uno::Reference<css::io::XStream> const & xStream) override;
 };
 
 DocumentDigitalSignatures::DocumentDigitalSignatures( const Reference< XComponentContext >& rxCtx ):
@@ -749,6 +754,42 @@ void DocumentDigitalSignatures::addLocationToTrustedSources( const OUString& Loc
     aSecOpt.SetSecureURLs( aSecURLs );
 }
 
+sal_Bool DocumentDigitalSignatures::signDocumentWithCertificate(
+            css::uno::Reference<css::security::XCertificate> const & xCertificate,
+            css::uno::Reference<css::embed::XStorage> const & xStorage,
+            css::uno::Reference<css::io::XStream> const & xStream)
+{
+    DocumentSignatureManager aSignatureManager(mxCtx, DocumentSignatureMode::Content);
+
+    if (!aSignatureManager.init())
+        return false;
+
+    aSignatureManager.mxStore = xStorage;
+    aSignatureManager.maSignatureHelper.SetStorage(xStorage, m_sODFVersion);
+    aSignatureManager.mxSignatureStream = xStream;
+
+    Reference<XXMLSecurityContext> xSecurityContext;
+    Reference<XServiceInfo> xServiceInfo(xCertificate, UNO_QUERY);
+    xSecurityContext = aSignatureManager.getSecurityContext();
+
+    sal_Int32 nSecurityId;
+
+    bool bSuccess = aSignatureManager.add(xCertificate, xSecurityContext, "", nSecurityId, true);
+    if (!bSuccess)
+        return false;
+
+    aSignatureManager.read(/*bUseTempStream=*/true, /*bCacheLastSignature=*/false);
+    aSignatureManager.write(true);
+
+    if (xStorage.is() && !xStream.is())
+    {
+        uno::Reference<embed::XTransactedObject> xTransaction(xStorage, uno::UNO_QUERY);
+        xTransaction->commit();
+    }
+
+    return true;
+}
+
 extern "C" SAL_DLLPUBLIC_EXPORT uno::XInterface*
 com_sun_star_security_DocumentDigitalSignatures_get_implementation(
     uno::XComponentContext* pCtx, uno::Sequence<uno::Any> const& /*rSeq*/)