(Chilkat2-Python) IMAP Download and Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

Chilkat2 Python Downloads install with pip pip3 install chilkat2 or download... Python Module for Windows, Linux, Alpine Linux, MacOS

import sys
import chilkat2

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

imap = chilkat2.Imap()

# Connect to an IMAP server.
# Use TLS
imap.Ssl = True
imap.Port = 993
success = imap.Connect("imap.someMailServer.com")
if (success != True):
    print(imap.LastErrorText)
    sys.exit()

success = imap.Login("myLogin","myPassword")
if (success != True):
    print(imap.LastErrorText)
    sys.exit()

# Select an IMAP mailbox
success = imap.SelectMailbox("Inbox")
if (success != True):
    print(imap.LastErrorText)
    sys.exit()

# We can choose to fetch UIDs or sequence numbers.
fetchUids = True

# Get the message IDs of all the emails in the mailbox
# messageSet is a CkMessageSet
messageSet = imap.Search("ALL",fetchUids)
if (imap.LastMethodSuccess != True):
    print(imap.LastErrorText)
    sys.exit()

# Scan for emails with attachments, and save the attachments
# to a sub-directory.
i = 0
while i < messageSet.Count :

    uid = messageSet.GetId(i)
    print("uid: " + uid)

    # email is a CkEmail
    email = imap.FetchSingle(uid,True)

    # The security layers of signed and/or encrypted emails
    # are automatically "unwrapped" when loaded into
    # a Chilkat email object.
    # An application only needs to check to see if an email
    # was received signed or encrypted, and then examine
    # the success/failure.  For example:
    if (email.ReceivedSigned == True):

        print("This email was signed.")

        # Check to see if the signatures were verified.
        if (email.SignaturesValid == True):
            print("Digital signature(s) verified.")

            print("Signer: " + email.SignedBy)

            # The certificate used for signing may be obtained
            # by calling email.GetSignedByCert.
            # cert is a CkCert
            cert = email.GetSignedByCert()
            if (email.LastMethodSuccess != True):
                print("Failed to get signing certificate object.")
            else:
                print("Signing cert: " + cert.SubjectCN)

        else:
            print("Digital signature verification failed.")

    i = i + 1

# Disconnect from the IMAP server.
success = imap.Disconnect()