(chicken process-context posix)
(chicken condition)
(chicken sort)
+ (chicken random)
srfi-1 srfi-13 matchable base64)
-(define lambdamail-version "LambdaMail v1.2.0")
+(define lambdamail-version "LambdaMail v1.7.0")
(define-record config host port spool-dir user group)
-(define-record message to from text user password)
-(define (make-empty-message) (make-message "" "" "" "" ""))
(define (time-stamp)
(time->string (seconds->local-time) "%d %b %Y %T %z"))
(server-loop listener config (deliver-messages config messages))))
+;;; Messages
+;;
+
+(define-record message to from text user password stamp)
+(define-record multi-message tos from text user password stamps)
+(define (make-empty-multi-message) (make-multi-message '() "" "" "" "" '()))
+
+
;;; Receiving messages
;;
messages))
(define (make-smtp-session in-port out-port config)
- (let ((user "")
- (password "")
- (helo ""))
+ (let ((helo ""))
(lambda command
(match command
(('get-line) (read-line in-port))
(('send strings ...) (write-line (conc (apply conc strings) "\r") out-port))
- (('set-user! u) (set! user u))
- (('set-password! p) (set! password p))
(('set-helo! h) (set! helo h))
- (('user) user)
- (('password) password)
(('helo) helo)))))
(define (smtp-command? cmd-string input-string)
(define (process-smtp smtp-session config)
(smtp-session 'send "220 " (config-host config) " " lambdamail-version)
- (let loop ((msg (make-empty-message))
+ (let loop ((mmsg (make-empty-multi-message))
(received-messages '()))
(let ((line (smtp-session 'get-line)))
(print "got " line)
((smtp-command? "helo" line)
(smtp-session 'set-helo! (smtp-command-args "helo" line))
(smtp-session 'send "250 ok")
- (loop msg received-messages))
+ (loop mmsg received-messages))
((smtp-command? "ehlo" line)
(smtp-session 'set-helo! (smtp-command-args "helo" line))
(smtp-session 'send
" Hello " (smtp-command-args "ehlo" line))
(smtp-session 'send "250 AUTH PLAIN")
;; (smtp-session 'send "250 STARTTLS")
- (loop msg received-messages))
+ (loop mmsg received-messages))
((smtp-command? "auth plain" line)
(let* ((auth-string (smtp-command-args "auth plain" line))
(auth-decoded (base64-decode auth-string))
(auth-list (string-split auth-decoded "\x00"))
(user (car auth-list))
(password (cadr auth-list)))
- (smtp-session 'set-user! user)
- (smtp-session 'set-password! password)
+ (multi-message-user-set! mmsg user)
+ (multi-message-password-set! mmsg password)
(print "Attempted login, user: " user ", password: " password)
(smtp-session 'send "235 authentication successful")
- (loop msg received-messages)))
+ (loop mmsg received-messages)))
((smtp-command? "mail from:" line)
- (message-from-set! msg (smtp-command-args "mail from:" line))
+ (multi-message-from-set! mmsg (smtp-command-args "mail from:" line))
(smtp-session 'send "250 ok")
- (loop msg received-messages))
+ (loop mmsg received-messages))
((smtp-command? "rcpt to:" line)
- (message-to-set! msg (smtp-command-args "rcpt to:" line))
- (smtp-session 'send "250 ok")
- (loop msg received-messages))
+ (let* ((to (smtp-command-args "rcpt to:" line))
+ (stamp (make-message-stamp to mmsg config)))
+ (print to)
+ (if (car stamp)
+ (begin
+ (multi-message-tos-set! mmsg (cons to (multi-message-tos mmsg)))
+ (multi-message-stamps-set! mmsg (cons stamp (multi-message-stamps mmsg)))
+ (smtp-session 'send "250 ok"))
+ (begin
+ (smtp-session 'send "551 relay forbidden"))))
+ (loop mmsg received-messages))
((smtp-command? "data" line)
(smtp-session 'send "354 intermediate")
- (let text-loop ((text (conc "Received: from " (smtp-session 'helo) "\n"
- "\tby " (config-host config) "\n"
- "\tfor " (message-to msg) ";\n"
- "\t" (time-stamp) "\n")))
+ (let text-loop ((text ""))
(let ((text-line (smtp-session 'get-line)))
(if (string=? "." text-line)
- (message-text-set! msg text)
+ (multi-message-text-set! mmsg text)
(text-loop (conc text text-line "\n")))))
- (message-user-set! msg (smtp-session 'user))
- (message-password-set! msg (smtp-session 'password))
(smtp-session 'send "250 ok")
- (loop (make-empty-message) (cons msg received-messages)))
+ (loop (make-empty-multi-message)
+ (append (make-single-recipient-messages mmsg smtp-session config)
+ received-messages)))
((smtp-command? "quit" line)
(smtp-session 'send "221 closing transmission channel")
received-messages)
((string=? "" (string-trim line))
- (loop msg received-messages))
+ (loop mmsg received-messages))
(else
(smtp-session 'send "502 command not implemented")
- (loop msg received-messages)))))))
+ (loop mmsg received-messages)))))))
+
+(define (make-single-recipient-messages mmsg smtp-session config)
+ (map
+ (lambda (to stamp)
+ (print "making singleton messages: " to " " stamp)
+ (make-message to (multi-message-from mmsg)
+ (conc "Received: from " (smtp-session 'helo) "\n"
+ "\tby " (config-host config) "\n"
+ "\tfor " to ";\n"
+ "\t" (time-stamp) "\n"
+ (multi-message-text mmsg))
+ (multi-message-user mmsg)
+ (multi-message-password mmsg)
+ stamp))
+ (multi-message-tos mmsg)
+ (multi-message-stamps mmsg)))
+
+
+;;; Message stamping and validation
+;;
+
+(define (get-local-addresses config)
+ (map (lambda (p) (cons
+ (conc "<" (car p) "@" (config-host config) ">")
+ (cdr p)))
+ (map (lambda (file)
+ (list (pathname-file file) file
+ (let ((password-file (conc file ".auth")))
+ (if (file-exists? password-file)
+ (with-input-from-file password-file read-line)
+ #f))))
+ (filter directory-exists?
+ (glob (conc (config-spool-dir config) "/*"))))))
+
+(define (make-message-stamp to mmsg config)
+ (let* ((local-addresses (get-local-addresses config))
+ (local-dest (assoc to local-addresses))
+ (local-src (assoc (multi-message-from mmsg) local-addresses)))
+ (cond
+ (local-dest
+ (list #t 'local (cadr local-dest)))
+ (local-src
+ (let ((host-password (caddr local-src)))
+ (if (and (string=? (conc "<" (multi-message-user mmsg) "@" (config-host config) ">")
+ (multi-message-from mmsg))
+ host-password
+ (string=? (multi-message-password mmsg) host-password))
+ (list #t 'remote)
+ (begin
+ (print "Provided password " (multi-message-password mmsg))
+ (print "Host password " host-password)
+ (list #f 'remote)))))
+ (else
+ (list #f 'relay)))))
;;; Sending/Delivering messages
(print "From: " (message-from msg))
(print "To: " (message-to msg))
(condition-case
- (let* ((local-addresses (get-local-addresses config))
- (dest (assoc (message-to msg) local-addresses))
- (orig (assoc (message-from msg) local-addresses)))
- (cond
- (dest
- (let ((dest-dir (cadr dest)))
- (deliver-message-local msg dest-dir)))
- (orig
- (let ((password (caddr orig)))
- (if (and (string=? (conc "<" (message-user msg) "@" (config-host config) ">")
- (message-from msg))
- password
- (string=? (message-password msg) password))
- (deliver-message-remote msg config)
- (begin
- (print "* REMOTE DELIVERY NOT ALLOWED (auth failure)")
- #t))))
- (else
- (print "* REMOTE DELIVERY REJECTED (relay forbidden)")
- #t)))
+ (match (message-stamp msg)
+ ((#t 'local dest-dir) (deliver-message-local msg dest-dir))
+ ((#t 'remote) (deliver-message-remote msg config))
+ ((#f 'remote)
+ (print "* REMOTE DELIVERY NOT ALLOWED (auth failure)")
+ #t)
+ (else
+ (print "* DELIVERY NOT ALLOWED (relay forbidden)")
+ #t))
(o (exn)
(print "* DELIVERY FAILED")
(print-error-message o)
#t)))
-
;; Local delivery
-(define (get-local-addresses config)
- (map (lambda (p) (cons
- (conc "<" (car p) "@" (config-host config) ">")
- (cdr p)))
- (map (lambda (file)
- (list (pathname-file file) file
- (let ((password-file (conc file ".auth")))
- (if (file-exists? password-file)
- (with-input-from-file password-file read-line)
- #f))))
- (filter directory-exists?
- (glob (conc (config-spool-dir config) "/*"))))))
+(define unique-file-name
+ (let ((counter 0))
+ (lambda ()
+ (set! counter (modulo (+ counter 1) 1000))
+ (conc (current-seconds) "_" counter))))
(define (deliver-message-local msg dest-dir)
- (with-output-to-file (conc dest-dir "/" (current-seconds))
+ (with-output-to-file (conc dest-dir "/" (unique-file-name))
(lambda ()
(print (message-text msg))))
(print "* MESSAGE DELIVERED (local)")
;; This is a hack - there's no built-in interface to res_query()
;; in chicken, so we have to resort to a system call to dig...
-(define (get-mail-server-for-domain domain)
+(define (get-mail-servers-for-domain domain)
(let* ((mx-lines (let-values (((in out id) (process (conc "dig " domain " mx +short"))))
(with-input-from-port in read-lines)))
(mx-entries (map (lambda (l)
(list (string->number (car s))
(string-drop-right (cadr s) 1)))) ; remove trailing "."
mx-lines))
- (sorted-mx-entries (sort mx-entries (lambda (e f) (< (car e) (car f))))))
+ (sorted-mx-entries (map cadr (sort mx-entries (lambda (e f) (< (car e) (car f)))))))
(if (null? sorted-mx-entries)
- domain ; fall-back to email address domain if no mx entries
- (cadar sorted-mx-entries)))) ; otherwise pick the highest priority server
+ (list domain) ; fall-back to email address domain if no mx entries
+ sorted-mx-entries))) ; otherwise pick the highest priority server
(define (deliver-message-remote msg config)
- (let* ((domain (get-domain-from-email (message-to msg)))
- (mail-server (get-mail-server-for-domain domain)))
- (print "Attempting delivery to " mail-server)
- (let-values (((tcp-in tcp-out) (tcp-connect mail-server 25)))
- (let ((smtp-session (make-outgoing-smtp-session tcp-in tcp-out)))
- (let ((result (and
- (smtp-session 'expect "2")
- (smtp-session 'send "helo " (config-host config))
- (smtp-session 'expect "2")
- (smtp-session 'send "mail from:" (message-from msg))
- (smtp-session 'expect "2")
- (smtp-session 'send "rcpt to:" (message-to msg))
- (smtp-session 'expect "2")
- (smtp-session 'send "data")
- (smtp-session 'expect "354")
- (smtp-session 'send (message-text msg))
- (smtp-session 'send ".")
- (smtp-session 'expect "2" "5") ;Do not try again on rejects.
- (smtp-session 'send "quit"))))
- (close-input-port tcp-in)
- (close-output-port tcp-out)
- (print "Connection closed.")
- (if result
- (print "* MESSAGE DELIVERED (remote)")
- (print "* REMOTE DELIVERY FAILED (unexpected server response)"))
- result)))))
+ (let ((domain (get-domain-from-email (message-to msg))))
+ (let loop ((mail-servers (get-mail-servers-for-domain domain)))
+ (if (null? mail-servers)
+ (begin
+ (print "* REMOTE DELIVERY FAILED (Could not connect to any mail server)")
+ #f)
+ (condition-case
+ (let ((mail-server (car mail-servers)))
+ (print "Attempting delivery to " mail-server)
+ (let-values (((tcp-in tcp-out) (tcp-connect mail-server 25)))
+ (let ((smtp-session (make-outgoing-smtp-session tcp-in tcp-out)))
+ (let ((result (and
+ (smtp-session 'expect "220")
+ (smtp-session 'send "helo " (config-host config))
+ (smtp-session 'expect "250")
+ (smtp-session 'send "mail from:" (message-from msg))
+ (smtp-session 'expect "250")
+ (smtp-session 'send "rcpt to:" (message-to msg))
+ (smtp-session 'expect "250")
+ (smtp-session 'send "data")
+ (smtp-session 'expect "354")
+ (smtp-session 'send (message-text msg))
+ (smtp-session 'send ".")
+ (smtp-session 'expect "250" "5") ;Do not try again on rejects.
+ (smtp-session 'send "quit"))))
+ (close-input-port tcp-in)
+ (close-output-port tcp-out)
+ (print "Connection closed.")
+ (if result
+ (print "* MESSAGE DELIVERED (remote)")
+ (print "* REMOTE DELIVERY FAILED (unexpected server response)"))
+ result))))
+ (o (exn)
+ (print-error-messsage o)
+ (print "* Failed to connect. Trying next server.")
+ (loop (cdr mail-servers))))))))
(define (or-list l)
(fold (lambda (a b) (or a b)) #f l))
(define ((make-outgoing-smtp-session tcp-in tcp-out) . command)
(match command
(('expect codes ...)
- (let ((result (read-line tcp-in)))
- (print "Expecting one of " codes " got " result)
- (or-list (map (lambda (code) (string-prefix? code result)) codes))))
+ (let loop ((result (read-line tcp-in)))
+ (if (and (> (string-length result) 3)
+ (eq? (string-ref result 3) #\-))
+ (loop (read-line tcp-in)) ;status continues on next line
+ (begin
+ (print "Expecting one of " codes " got " result)
+ (or-list (map (lambda (code)
+ (string-prefix? code result))
+ codes))))))
(('send strings ...)
(print "Sending " (if (> (string-length (car strings)) 30)
(string-take (car strings) 30)
(main)
;; (define (test)
- ;; (run-server (make-config "localhost" 2525 "spool" '() '())))
+;; (run-server (make-config "localhost" 2525 "spool" '() '())))
+
+;; (test)
The Lambda Lab / projects / lambdamail.git / blobdiff