Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
branch: master
Fetching contributors…

Cannot retrieve contributors at this time

423 lines (353 sloc) 13.955 kb
;;; A basic XMPP library which should conform to RFCs 3920 and 3921
;;;
;;; Copyright (C) 2009 FoAM vzw.
;;;
;;; This package is free software: you can redistribute it and/or
;;; modify it under the terms of the GNU Lesser General Public
;;; License as published by the Free Software Foundation, either
;;; version 3 of the License, or (at your option) any later version.
;;;
;;; This program is distributed in the hope that it will be useful,
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;; Lesser General Public License for more details.
;;;
;;; You can find a copy of the GNU Lesser General Public License at
;;; http://www.gnu.org/licenses/lgpl-3.0.html.
;;;
;;; Authors
;;;
;;; nik gaffney <nik@fo.am>
;;;
;;; Requirements
;;;
;;; PLT for now. TLS requires a version of PLT > 4.1.5.3
;;;
;;; Commentary
;;;
;;; Still a long way from implementing even a minimal subset of XMPP
;;;
;;; features implemented
;;; - plaintext sessions on port 5222
;;; - "old sytle" ssl sessions on port 5223 (default)
;;; - authenticate using an existing account
;;; - send messages (rfc 3921 sec.4)
;;; - send presence (rfc 3921 sec.5)
;;; - parse (some) xml reponses from server
;;; - handlers for responses
;;; - basic roster handling (rfc 3921 sec.7)
;;;
;;; features to implement
;;; - account creation
;;; - managing subscriptions & rosters (rfc 3921 sec.6 & 8)
;;; - error handling for rosters (rfc 3921 sec.7)
;;; - plaintext/tls/sasl negotiation (rfc 3920 sec.5 & 6)
;;; - encrypted connections using tls on port 5222
;;; - correct namespaces in sxml
;;; - message types
;;; - maintain session ids
;;; - maintain threads
;;; - error handling
;;; - events
;;; - [...]
;;; - rfc 3920
;;; - rfc 3921
;;;
;;; bugs and/or improvements
;;; - start & stop functions for multiple sessions
;;; - pubsub (XEP-0060) & group chats (XEP-0045)
;;; - 'send' using call/cc & parameterize'd i/o ports
;;; - coroutines for sasl negotiation
;;; - read-async & repsonse-handler
;;; - ssax:xml->sxml or lazy:xml->sxml
;;; - default handlers
;;; - syntax for defining sxpath based handlers
;;; - improve parsing
;;; - chatbot exmples
;;;
(module xmpp scheme
(require (planet lizorkin/sxml:2:1/sxml)) ;; encoding xml
(require (planet lizorkin/ssax:2:0/ssax)) ;; decoding xml
(require mzlib/os) ;; hostname
(require scheme/tcp) ;; networking
(require openssl) ;; ssl/tls
(require srfi/13) ;; jid decoding
(provide (all-defined-out))
;;;; ; ;; ;
;;
;; debugging
;;
;;;; ; ;
(define debug? #t)
(define debugf
(case-lambda
((str) (when debug? (printf str)))
((str . dir) (when debug? (apply printf (cons str dir))))))
;;;;;;;;;;; ; ;;;; ; ;;; ; ; ;; ;
;;
;; networking
;;
;;;;;; ;; ;; ; ; ; ;
(define port 5222)
(define ssl-port 5223)
(define (open-connection machine port handler)
(let-values (((in out)
(tcp-connect machine port)))
(handler in out)
(close-output-port out)
(close-input-port in)))
(define (open-ssl-connection machine port handler)
(let-values (((in out)
(ssl-connect machine port 'tls)))
(handler in out)
(close-output-port out)
(close-input-port in)))
(define (read-async in)
(bytes->string/utf-8 (list->bytes (read-async-bytes in))))
(define (read-async-bytes in)
(let ((bstr '()))
(when (sync/timeout 0 in)
(set! bstr (cons (read-byte in) (read-async-bytes in)))) bstr))
(define ssxml srl:sxml->xml-noindent)
;;;;;; ; ; ; ; ;; ;;;;;; ;
;;
;; XMPP stanzas
;;
;;;;;;;;;; ;;; ; ;; ; ;
;; intialization
(define (xmpp-stream host)
(string-append "<?xml version='1.0'?>" ;; version='1.0' is a MUST for SASL on 5222 but NOT for ssl on 5223
"<stream:stream xmlns:stream='http://etherx.jabber.org/streams' to='"
host
"' xmlns='jabber:client' >"))
;; authentication
(define (xmpp-auth username password resource)
(ssxml `(iq (@ (type "set") (id "auth"))
(query (@ (xmlns "jabber:iq:auth"))
(username ,username)
(password ,password)
(resource ,resource)))))
(define (xmpp-session host)
(ssxml `(iq (@ (to ,host) (type "set") (id "session"))
(session (@ (xmlns "urn:ietf:params:xml:ns:xmpp-session"))))))
;; messages
(define (message to body)
(ssxml `(message (@ (to ,to)) (body ,body))))
;; presence
(define (presence #:from (from "")
#:to (to "")
#:type (type "")
#:show (show "")
#:status (status ""))
(cond ((not (string=? status ""))
(ssxml `(presence (@ (type "probe")) (status ,status))))
((string=? type "") "<presence/>")
(else (ssxml `(presence (@ (type ,type)))))))
;; queries
(define (iq body
#:from (from "")
#:to (to "")
#:type (type "")
#:id (id ""))
(ssxml `(iq (@ (to ,to) (type ,type) ,body))))
;; curried stanza disection (sxml stanza -> string)
(define ((sxpath-element xpath (ns "")) stanza)
(let ((node ((sxpath xpath (list (cons 'ns ns))) stanza)))
(if (empty? node) "" (car node))))
;; message
(define message-from (sxpath-element "message/@from/text()"))
(define message-to (sxpath-element "message/@to/text()"))
(define message-id (sxpath-element "message/@id/text()"))
(define message-type (sxpath-element "message/@type/text()"))
(define message-body (sxpath-element "message/body/text()"))
(define message-subject (sxpath-element "message/subject/text()"))
;; info/query
(define iq-type (sxpath-element "iq/@type/text()"))
(define iq-id (sxpath-element "iq/@id/text()"))
(define iq-error-type (sxpath-element "iq/error/@type/text()"))
(define iq-error-text (sxpath-element "iq/error/text()"))
(define iq-error (sxpath-element "iq/error"))
;; presence
(define presence-show (sxpath-element "presence/show/text()"))
(define presence-from (sxpath-element "presence/@from/text()"))
(define presence-status (sxpath-element "presence/status/text()"))
;;;;;;;;;; ; ; ; ;; ;
;;
;; rosters
;;
;;;;;; ; ;; ;
;; request the roster from server
(define (request-roster from)
(ssxml `(iq (@ (from ,from) (type "get") (id "roster_1"))
(query (@ (xmlns "jabber:iq:roster"))))))
;; add an item to the roster
(define (add-to-roster from jid name group)
(ssxml `(iq (@ (from ,from) (type "set") (id "roster_2"))
(query (@ (xmlns "jabber:iq:roster"))
(item (@ (jid ,jid) (name ,name))
(group ,group))))))
;; update an item in the roster
(define (update-roster from jid name group)
(ssxml `(iq (@ (from ,from) (type "set") (id "roster_3"))
(query (@ (xmlns "jabber:iq:roster"))
(item (@ (jid ,jid) (name ,name))
(group ,group))))))
;; remove an item from the roster
(define (remove-from-roster from jid)
(ssxml `(iq (@ (from ,from) (type "set") (id "roster_4"))
(query (@ (xmlns "jabber:iq:roster"))
(item (@ (jid ,jid) (subscription "remove")))))))
;;;;; ; ; ;; ; ;
;;
;; in-band registration
;;
;;;;;; ;; ;; ;
(define (reg1)
(ssxml `(iq (@ (type "get") (id "reg1"))
(query (@ (xmlns "jabber:iq:register"))))))
;;;; ;; ; ;;; ;
;;
;; tls & sasl
;; - http://xmpp.org/rfcs/rfc3920.html#tls
;; - http://xmpp.org/rfcs/rfc3920.html#sasl
;;
;;;; ;;
(define session->tls? #f) ;; changes state when a tls proceed is recived
;; moved to xmpp-sasl until it 'works'
;;;;;;;;; ; ;; ; ; ;; ;; ; ;
;;
;; parsing & message/iq/error handlers
;; - minimal parsing
;; - handlers match on a tag (eg. 'message)
;; - handlers are called with a single relevant xmpp stanza
;;
;;;;;; ;; ; ; ;; ;
(define xmpp-handlers (make-hash)) ;; a hash of tags and functions (possibly extend to using sxpaths and multiple handlers)
(define (set-xmpp-handler type fcn)
(dict-set! xmpp-handlers type fcn))
(define (remove-xmpp-handler type fcn)
(dict-remove! xmpp-handlers type fcn))
(define (run-xmpp-handler type sz)
(let ((fcn (dict-ref xmpp-handlers type #f)))
(when fcn (begin
(debugf "attempting to run handler ~a.~%" fcn)
(fcn sz)))))
;; no real parsing yet. dispatches any received xml stanzas as sxml
(define (parse-xmpp-response str)
(when (> (string-length str) 0)
(let ((sz (ssax:xml->sxml (open-input-string (clean str)) '())))
;;(let ((sz (lazy:xml->sxml (open-input-string str) '())))
(cond
((equal? '(null) (cadr sz))
(newline))
((equal? 'message (caadr sz))
(run-xmpp-handler 'message sz))
((equal? 'iq (caadr sz))
(run-xmpp-handler 'iq sz))
((equal? 'presence (caadr sz))
(run-xmpp-handler 'presence sz))
(else (run-xmpp-handler 'other sz))))))
;; example handlers to print stanzas or their contents
(define (print-message sz)
(printf "a ~a message from ~a which says '~a.'~%" (message-type sz) (message-from sz) (message-body sz)))
(define (print-iq sz)
(printf "an iq response of type '~a' with id '~a.'~%" (iq-type sz) (iq-id sz)))
(define (print-presence sz)
(printf " p-r-e-s-e-n-e-c--> ~a is ~a" (presence-from sz) (presence-status)))
(define (print-stanza sz)
(printf "? ?? -> ~%~a~%" sz))
;; handler to print roster
(define (roster-jids sz)
((sxpath "iq/ns:query/ns:item/@jid/text()" '(( ns . "jabber:iq:roster"))) sz))
(define (roster-items sz)
((sxpath-element "iq/ns:query/ns:item" '(( ns . "jabber:iq:roster"))) sz))
(define (print-roster sz)
(when (and (string=? (iq-type sz) "result")
(string=? (iq-id sz) "roster_1"))
(printf "~a~%" (roster-jids sz))))
;; QND hack to filter out anything not a message, iq or presence
(define (clean str)
(let ((test (substring str 0 3)))
(cond ((string-ci=? test "<me") str)
((string-ci=? test "<iq") str)
((string-ci=? test "<pr") str)
((string-ci=? test "<ur") str)
(else
(debugf "~%recieved: ~a ~%parsed as <null/>~%~%" str)
"<null/>"))))
;; response handler
(define (xmpp-response-handler in)
(thread (lambda ()
(let loop ()
(parse-xmpp-response (read-async in))
(sleep 0.1) ;; slight delay to avoid a tight loop
(loop)))))
;; jid splicing (assuming the jid is in the format user@host/resource)
(define (jid-user jid)
(string-take jid (string-index jid #\@)))
(define (jid-host jid)
(let* ((s (string-take-right jid (- (string-length jid) (string-index jid #\@) 1)))
(v (string-index s #\/)))
(if v (string-take s v) s )))
(define (jid-resource jid)
(let ((r (jid-resource-0 jid)))
(if (void? r) (gethostname) r)))
(define (jid-resource-0 jid)
(let ((v (string-index jid #\/)))
(when v (string-take-right jid (- (string-length jid) v 1)))))
;;;; ;; ; ; ;; ;; ;;;; ;
;;
;; interfaces
;;
;;;;; ;; ;;;; ; ;; ;
(define xmpp-in-port (make-parameter #f))
(define xmpp-out-port (make-parameter #F))
(define (send str)
(debugf "sending: ~a ~%~%" str)
(let* ((p-out (xmpp-out-port))
(out (if p-out p-out xmpp-out-port-v)))
(fprintf out "~A~%" str) (flush-output out)))
(define-syntax with-xmpp-session
(syntax-rules ()
((_ jid pass form . forms)
(let ((host (jid-host jid))
(user (jid-user jid))
(resource (jid-resource jid)))
(let-values (((in out)
(ssl-connect host ssl-port 'tls)))
;;(tcp-connect host port)))
(parameterize ((xmpp-in-port in)
(xmpp-out-port out))
(file-stream-buffer-mode out 'line)
(xmpp-response-handler in)
(send (xmpp-stream host))
(send (xmpp-session host))
;(starttls in out)
(send (xmpp-auth user pass resource))
(send (presence))
(begin form . forms)
(close-output-port out)
(close-input-port in)))))))
;; NOTE: this will only work with a single connection to a host, however multiple sessions to that host may be possible
(define xmpp-in-port-v (current-input-port))
(define xmpp-out-port-v (current-output-port))
(define (start-xmpp-session jid pass)
(let ((host (jid-host jid))
(user (jid-user jid))
(resource (jid-resource jid)))
(let-values (((in out)
(ssl-connect host ssl-port 'tls)))
;;(tcp-connect host port)))
(set! xmpp-in-port-v in)
(set! xmpp-out-port-v out)
(file-stream-buffer-mode out 'line)
(xmpp-response-handler in)
(send (xmpp-stream host))
(send (xmpp-session host))
;;(starttls in out)
(send (xmpp-auth user pass resource))
(send (presence)))))
(define (close-xmpp-session)
(close-output-port xmpp-out-port-v)
(close-input-port xmpp-in-port-v))
) ;; end module
Jump to Line
Something went wrong with that request. Please try again.