Tcl

POP3 Verify Signed (S/MIME) Email

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

load ./chilkat.dll

set success 0

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

set mailman [new_CkMailMan]

# Set the POP3 server's hostname
CkMailMan_put_MailHost $mailman "pop.example.com"

# Set the POP3 login/password.
CkMailMan_put_PopUsername $mailman "myLogin"
CkMailMan_put_PopPassword $mailman "myPassword"

set stUidls [new_CkStringTable]

set success [CkMailMan_FetchUidls $mailman $stUidls]
if {$success == 0} then {
    puts [CkMailMan_lastErrorText $mailman]
    delete_CkMailMan $mailman
    delete_CkStringTable $stUidls
    exit
}

set email [new_CkEmail]

set cert [new_CkCert]

set count [CkStringTable_get_Count $stUidls]
set i 0
while {$i < $count} {
    # Download the full email.
    set success [CkMailMan_FetchByUidl $mailman [CkStringTable_stringAt $stUidls $i] 0 0 $email]
    if {$success == 0} then {
        puts [CkMailMan_lastErrorText $mailman]
        delete_CkMailMan $mailman
        delete_CkStringTable $stUidls
        delete_CkEmail $email
        delete_CkCert $cert
        exit
    }

    puts "$i"
    puts "From: [CkEmail_from $email]"
    puts "Subject: [CkEmail_subject $email]"

    # 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 {[CkEmail_get_ReceivedSigned $email] == 1} then {

        puts "This email was signed."

        # Check to see if the signatures were verified.
        if {[CkEmail_get_SignaturesValid $email] == 1} then {
            puts "Digital signature(s) verified."
            puts "Signer: [CkEmail_signedBy $email]"

            set success [CkEmail_LastSignerCert $email 0 $cert]
            if {$success == 0} then {
                puts [CkEmail_lastErrorText $email]
                delete_CkMailMan $mailman
                delete_CkStringTable $stUidls
                delete_CkEmail $email
                delete_CkCert $cert
                exit
            }

            puts "Signing cert: [CkCert_subjectCN $cert]"
        }

    }     else {
        puts "Digital signature verification failed."
    }

    set i [expr $i + 1]
}

CkMailMan_Pop3EndSession $mailman

delete_CkMailMan $mailman
delete_CkStringTable $stUidls
delete_CkEmail $email
delete_CkCert $cert