lisp/url/url-gw.el

   1 ;;; url-gw.el --- Gateway munging for URL loading
   2
   3 ;; Copyright (C) 1997, 1998, 2004, 2005, 2006 Free Software Foundation, Inc.
   4
   5 ;; Author: Bill Perry <wmperry@gnu.org>
   6 ;; Keywords: comm, data, processes
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 2, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23 ;; Boston, MA 02110-1301, USA.
  24
  25 ;;; Code:
  26
  27 (eval-when-compile (require 'cl))
  28 (require 'url-vars)
  29
  30 ;; Fixme: support SSH explicitly or via a url-gateway-rlogin-program?
  31
  32 (autoload 'socks-open-network-stream "socks")
  33 (autoload 'open-ssl-stream "ssl")
  34 (autoload 'open-tls-stream "tls")
  35
  36 (defgroup url-gateway nil
  37   "URL gateway variables."
  38   :group 'url)
  39
  40 (defcustom url-gateway-local-host-regexp nil
  41   "*A regular expression specifying local hostnames/machines."
  42   :type '(choice (const nil) regexp)
  43   :group 'url-gateway)
  44
  45 (defcustom url-gateway-prompt-pattern
  46   "^[^#$%>;]*[#$%>;] *" ;; "bash\\|\$ *\r?$\\|> *\r?"
  47   "*A regular expression matching a shell prompt."
  48   :type 'regexp
  49   :group 'url-gateway)
  50
  51 (defcustom url-gateway-rlogin-host nil
  52   "*What hostname to actually rlog into before doing a telnet."
  53   :type '(choice (const nil) string)
  54   :group 'url-gateway)
  55
  56 (defcustom url-gateway-rlogin-user-name nil
  57   "*Username to log into the remote machine with when using rlogin."
  58   :type '(choice (const nil) string)
  59   :group 'url-gateway)
  60
  61 (defcustom url-gateway-rlogin-parameters '("telnet" "-8")
  62   "*Parameters to `url-open-rlogin'.
  63 This list will be used as the parameter list given to rsh."
  64   :type '(repeat string)
  65   :group 'url-gateway)
  66
  67 (defcustom url-gateway-telnet-host nil
  68   "*What hostname to actually login to before doing a telnet."
  69   :type '(choice (const nil) string)
  70   :group 'url-gateway)
  71
  72 (defcustom url-gateway-telnet-parameters '("exec" "telnet" "-8")
  73   "*Parameters to `url-open-telnet'.
  74 This list will be executed as a command after logging in via telnet."
  75   :type '(repeat string)
  76   :group 'url-gateway)
  77
  78 (defcustom url-gateway-telnet-login-prompt "^\r*.?login:"
  79   "*Prompt that tells us we should send our username when loggin in w/telnet."
  80   :type 'regexp
  81   :group 'url-gateway)
  82
  83 (defcustom url-gateway-telnet-password-prompt "^\r*.?password:"
  84   "*Prompt that tells us we should send our password when loggin in w/telnet."
  85   :type 'regexp
  86   :group 'url-gateway)
  87
  88 (defcustom url-gateway-telnet-user-name nil
  89   "User name to log in via telnet with."
  90   :type '(choice (const nil) string)
  91   :group 'url-gateway)
  92
  93 (defcustom url-gateway-telnet-password nil
  94   "Password to use to log in via telnet with."
  95   :type '(choice (const nil) string)
  96   :group 'url-gateway)
  97
  98 (defcustom url-gateway-broken-resolution nil
  99   "*Whether to use nslookup to resolve hostnames.
 100 This should be used when your version of Emacs cannot correctly use DNS,
 101 but your machine can.  This usually happens if you are running a statically
 102 linked Emacs under SunOS 4.x"
 103   :type 'boolean
 104   :group 'url-gateway)
 105
 106 (defcustom url-gateway-nslookup-program "nslookup"
 107   "*If non-NIL then a string naming nslookup program."
 108   :type '(choice (const :tag "None" :value nil) string)
 109   :group 'url-gateway)
 110
 111 ;; Stolen from ange-ftp
 112 ;;;###autoload
 113 (defun url-gateway-nslookup-host (host)
 114   "Attempt to resolve the given HOST using nslookup if possible."
 115   (interactive "sHost:  ")
 116   (if url-gateway-nslookup-program
 117       (let ((proc (start-process " *nslookup*" " *nslookup*"
 118                                  url-gateway-nslookup-program host))
 119             (res host))
 120         (set-process-query-on-exit-flag proc nil)
 121         (with-current-buffer (process-buffer proc)
 122           (while (memq (process-status proc) '(run open))
 123             (accept-process-output proc))
 124           (goto-char (point-min))
 125           (if (re-search-forward "Name:.*\nAddress: *\\(.*\\)$" nil t)
 126               (setq res (buffer-substring (match-beginning 1)
 127                                           (match-end 1))))
 128           (kill-buffer (current-buffer)))
 129         res)
 130     host))
 131
 132 ;; Stolen from red gnus nntp.el
 133 (defun url-wait-for-string (regexp proc)
 134   "Wait until string matching REGEXP arrives in process PROC's buffer."
 135   (let ((buf (current-buffer)))
 136     (goto-char (point-min))
 137     (while (not (re-search-forward regexp nil t))
 138       (accept-process-output proc)
 139       (set-buffer buf)
 140       (goto-char (point-min)))))
 141
 142 ;; Stolen from red gnus nntp.el
 143 (defun url-open-rlogin (name buffer host service)
 144   "Open a connection using rsh."
 145   (if (not (stringp service))
 146       (setq service (int-to-string service)))
 147   (let ((proc (if url-gateway-rlogin-user-name
 148                   (start-process
 149                    name buffer "rsh"
 150                    url-gateway-rlogin-host "-l" url-gateway-rlogin-user-name
 151                    (mapconcat 'identity
 152                               (append url-gateway-rlogin-parameters
 153                                       (list host service)) " "))
 154                 (start-process
 155                  name buffer "rsh" url-gateway-rlogin-host
 156                  (mapconcat 'identity
 157                             (append url-gateway-rlogin-parameters
 158                                     (list host service))
 159                             " ")))))
 160     (set-buffer buffer)
 161     (url-wait-for-string "^\r*200" proc)
 162     (beginning-of-line)
 163     (delete-region (point-min) (point))
 164     proc))
 165
 166 ;; Stolen from red gnus nntp.el
 167 (defun url-open-telnet (name buffer host service)
 168   (if (not (stringp service))
 169       (setq service (int-to-string service)))
 170   (with-current-buffer (get-buffer-create buffer)
 171     (erase-buffer)
 172     (let ((proc (start-process name buffer "telnet" "-8"))
 173           (case-fold-search t))
 174       (when (memq (process-status proc) '(open run))
 175         (process-send-string proc "set escape \^X\n")
 176         (process-send-string proc (concat
 177                                    "open " url-gateway-telnet-host "\n"))
 178         (url-wait-for-string url-gateway-telnet-login-prompt proc)
 179         (process-send-string
 180          proc (concat
 181                (or url-gateway-telnet-user-name
 182                    (setq url-gateway-telnet-user-name (read-string "login: ")))
 183                "\n"))
 184         (url-wait-for-string url-gateway-telnet-password-prompt proc)
 185         (process-send-string
 186          proc (concat
 187                (or url-gateway-telnet-password
 188                    (setq url-gateway-telnet-password
 189                          (read-passwd "Password: ")))
 190                "\n"))
 191         (erase-buffer)
 192         (url-wait-for-string url-gateway-prompt-pattern proc)
 193         (process-send-string
 194          proc (concat (mapconcat 'identity
 195                                  (append url-gateway-telnet-parameters
 196                                          (list host service)) " ") "\n"))
 197         (url-wait-for-string "^\r*Escape character.*\r*\n+" proc)
 198         (delete-region (point-min) (match-end 0))
 199         (process-send-string proc "\^]\n")
 200         (url-wait-for-string "^telnet" proc)
 201         (process-send-string proc "mode character\n")
 202         (accept-process-output proc 1)
 203         (sit-for 1)
 204         (goto-char (point-min))
 205         (forward-line 1)
 206         (delete-region (point) (point-max)))
 207       proc)))
 208
 209 ;;;###autoload
 210 (defun url-open-stream (name buffer host service)
 211   "Open a stream to HOST, possibly via a gateway.
 212 Args per `open-network-stream'.
 213 Will not make a connection if `url-gateway-unplugged' is non-nil.
 214 Might do a non-blocking connection; use `process-status' to check."
 215   (unless url-gateway-unplugged
 216     (let ((gw-method (if (and url-gateway-local-host-regexp
 217                               (not (eq 'tls url-gateway-method))
 218                               (not (eq 'ssl url-gateway-method))
 219                               (string-match
 220                                url-gateway-local-host-regexp
 221                                host))
 222                          'native
 223                        url-gateway-method))
 224 ;;;     ;; This hack is for OS/2 Emacs so that it will not do bogus CRLF
 225 ;;;     ;; conversions while trying to be 'helpful'
 226 ;;;     (tcp-binary-process-output-services (if (stringp service)
 227 ;;;                                             (list service)
 228 ;;;                                           (list service
 229 ;;;                                                 (int-to-string service))))
 230
 231           ;; An attempt to deal with denied connections, and attempt
 232           ;; to reconnect
 233           (cur-retries 0)
 234           (retry t)
 235           (errobj nil)
 236           (conn nil))
 237
 238       ;; If the user told us to do DNS for them, do it.
 239       (if url-gateway-broken-resolution
 240           (setq host (url-gateway-nslookup-host host)))
 241
 242       (condition-case errobj
 243           ;; This is a clean way to ensure the new process inherits the
 244           ;; right coding systems in both Emacs and XEmacs.
 245           (let ((coding-system-for-read 'binary)
 246                 (coding-system-for-write 'binary))
 247             (setq conn (case gw-method
 248                          (tls
 249                           (open-tls-stream name buffer host service))
 250                          (ssl
 251                           (open-ssl-stream name buffer host service))
 252                          ((native)
 253                           ;; Use non-blocking socket if we can.
 254                           (make-network-process :name name :buffer buffer
 255                                                 :host host :service service
 256                                                 :nowait
 257                                                 (featurep 'make-network-process '(:nowait t))))
 258                          (socks
 259                           (socks-open-network-stream name buffer host service))
 260                          (telnet
 261                           (url-open-telnet name buffer host service))
 262                          (rlogin
 263                           (url-open-rlogin name buffer host service))
 264                          (otherwise
 265                           (error "Bad setting of url-gateway-method: %s"
 266                                  url-gateway-method)))))
 267         ;; Ignoring errors here seems wrong.  E.g. it'll throw away the
 268         ;; error signalled two lines above.  It was also found inconvenient
 269         ;; during debugging.
 270         ;; (error
 271         ;;  (setq conn nil))
 272         )
 273       conn)))
 274
 275 (provide 'url-gw)
 276
 277 ;; arch-tag: 1c4c0317-6d03-45b8-b3f3-838bd8f9d838
 278 ;;; url-gw.el ends here