CkPython

Sign PDF using PAdES-Baseline-B

See more PDF Signatures Examples

PAdES-Baseline-B is the most basic, entry-level profile of the PDF Advanced Electronic Signatures (PAdES) standard.

It means:

• A PDF contains a CMS/PKCS#7 detached signature over the document’s byte range.
• /SubFilter must be ETSI.CAdES.detached.
• The signer’s X.509 certificate is included inside the signature.
• The signature uses recognized secure algorithms (e.g., SHA-256 with RSA/ECDSA).
• It proves document integrity (no changes since signing) and signer authenticity (certificate identifies who signed).
• It does not include time-stamps, revocation data (CRL/OCSP), or long-term validation information — those appear only in higher levels (PAdES-Baseline-T, -LT, -LTA).

In short: Baseline-B = a standard PDF digital signature that ensures integrity and origin, but without time or revocation guarantees.

CkPython

import sys
import chilkat

success = False

pdf = chilkat.CkPdf()

# Load a PDF to be signed.
success = pdf.LoadFile("c:/someDir/my.pdf")
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

# Options for signing are specified in JSON.
json = chilkat.CkJsonObject()

json.UpdateString("subFilter","/ETSI.CAdES.detached")
json.UpdateBool("signingCertificateV2",True)
json.UpdateBool("signingTime",True)
json.UpdateString("signingAlgorithm","pkcs")
json.UpdateString("hashAlgorithm","sha256")

# -----------------------------------------------------------
# The following JSON settings define the signature appearance.
json.UpdateInt("page",1)
json.UpdateString("appearance.y","top")
json.UpdateString("appearance.x","left")
json.UpdateString("appearance.fontScale","10.0")
json.UpdateString("appearance.text[0]","Digitally signed by: cert_cn")
json.UpdateString("appearance.text[1]","current_dt")
json.UpdateString("appearance.text[2]","Hello 123 ABC")

# --------------------------------------------------------------
# Load the signing certificate. (Use your own certificate.)
# Note: There are other methods for using a certificate on an HSM (smartcard or token)
# or from other sources, such as a cloud HSM, a Windows installed certificate,
# or other file formats.
cert = chilkat.CkCert()
success = cert.LoadPfxFile("c:/myPfxFiles/myPdfSigningCert.pfx","pfxPassword")
if (success == False):
    print(cert.lastErrorText())
    sys.exit()

# Once we have the certificate object, tell the PDF object to use it for signing
success = pdf.SetSigningCert(cert)
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

# Sign the PDF, creating the output file.
outFilePath = "c:/someDir/mySigned.pdf"
success = pdf.SignPdf(json,outFilePath)
if (success == False):
    print(pdf.lastErrorText())
    sys.exit()

print("Success.")