Timbre Fiscal Digital (TFD) element

The TFD option operates on the tfd:TimbreFiscalDigital (TFD) element instead of the cfdi:Comprobante. Use to create the TFD pipestring (cadena original del timbre fiscal digital del SAT) and verify the selloSAT signature.
La opción de TFD actúa sobre el elemento de tfd:TimbreFiscalDigital (TFD) en lugar del elemento cfdi:Comprobante. Se utiliza para crear la cadena original del timbre fiscal digital del SAT y verificar la firma selloSAT.

Use the "-f" option in the commands PIPESTRING, VERIFYSIG, EXTRACTDIGEST, FORMDIGEST and MAKESIG.

For example, the following command will output the TFD pipestring (cadena original del timbre fiscal digital del SAT) from the tfd element (provided the element exists).

FirmaSAT PIPESTRING -f cfdv33a-signed-tfd.xml

||1.1|b2e2c132-01d6-4c62-a158-7ac932d0ec36|...

Use the SAT_TFD option in the VB6/C functions

• SAT_MakePipeStringFromXml
• SAT_VerifySignature
• SAT_ExtractDigestFromSignature
• SAT_MakeDigestFromXml
• SAT_MakeSignatureFromXmlEx

nchars = SAT_MakePipeStringFromXml(buf, nchars, fname, SAT_TFD);

Use the "tfd" wrapper functions in VBA/VB6:

• tfdMakePipeStringFromXml
• tfdMakeDigestFromXml
• tfdExtractDigestFromSignature
• tfdMakeSignatureFromXml
• tfdVerifySignature

Use the Tfd Class in C# and VB.NET with the methods

• Tfd.MakePipeStringFromXml
• Tfd.MakeDigestFromXml
• Tfd.MakeSignatureFromXml
• Tfd.ExtractDigestFromSignature
• Tfd.VerifySignature

These methods work in exactly the same way as the equivalent methods in the Sat Class, except they operate on an existing TFD element, not the Comprobante. The certificate parameter is compulsory for the VerifySignature and ExtractDigestFromSignature methods.

Adding a new TFD element

If you want to add a new signed TFD element to a signed CFDI document, see Adding a TFD element and the Tfd.AddSignedTfd method.