Lua Requires Chilkat v11.0.0+

IMAP Download and Verify Signed (S/MIME) Email

See more IMAP Examples

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

local chilkat = require("chilkat")

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

local imap = chilkat.Imap.new()

-- Connect to an IMAP server.
-- Use TLS
imap.ssl = true
imap.port = 993
local success = imap:connect("imap.example.com")
if not success then
    print(imap.last_error_text)
    return
end

success = imap:login("myLogin", "myPassword")
if not success then
    print(imap.last_error_text)
    return
end

-- Select an IMAP mailbox
success = imap:select_mailbox("Inbox")
if not success then
    print(imap.last_error_text)
    return
end

-- We can choose to fetch UIDs or sequence numbers.
local fetchUids = true

-- Get the message IDs of all the emails in the mailbox
local messageSet = chilkat.MessageSet.new()
success = imap:query_mbx("ALL", fetchUids, messageSet)
if not success then
    print(imap.last_error_text)
    return
end

local email = chilkat.Email.new()
local cert = chilkat.Cert.new()

local i = 0
while i < messageSet.count do
    local uid = messageSet:get_id(i)
    print("uid: " .. uid)

    success = imap:fetch_email(false, uid, true, email)
    if not success then
        print(imap.last_error_text)
        return
    end

    -- 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.received_signed then
        print("This email was signed.")

        -- Check to see if the signatures were verified.
        if email.signatures_valid then
            print("Digital signature(s) verified.")
            print("Signer: " .. email.signed_by)

            -- Get the certificate used for signing.
            success = email:last_signer_cert(0, cert)

            if not success then
                print("Failed to get signing certificate object.")
            else
                print("Signing cert: " .. cert.subject_cn)
            end
        else
            print("Digital signature verification failed.")
        end
    end

    i = i + 1
end

-- Disconnect from the IMAP server.
success = imap:disconnect()