lisp/gnus/pop3.el

   1 ;;; pop3.el --- Post Office Protocol (RFC 1460) interface
   2
   3 ;; Copyright (C) 1996,1997,1998 Free Software Foundation, Inc.
   4
   5 ;; Author: Richard L. Pieri <ratinox@peorth.gweep.net>
   6 ;; Keywords: mail, pop3
   7 ;; Version: 1.3m
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; Most of the standard Post Office Protocol version 3 (RFC 1460) commands
  29 ;; are implemented.  The LIST command has not been implemented due to lack
  30 ;; of actual usefulness.
  31 ;; The optional POP3 command TOP has not been implemented.
  32
  33 ;; This program was inspired by Kyle E. Jones's vm-pop program.
  34
  35 ;;; Code:
  36
  37 (require 'mail-utils)
  38 (provide 'pop3)
  39
  40 (defconst pop3-version "1.3m")
  41
  42 (defvar pop3-maildrop (or (user-login-name) (getenv "LOGNAME") (getenv "USER") nil)
  43   "*POP3 maildrop.")
  44 (defvar pop3-mailhost (or (getenv "MAILHOST") nil)
  45   "*POP3 mailhost.")
  46 (defvar pop3-port 110
  47   "*POP3 port.")
  48
  49 (defvar pop3-password-required t
  50   "*Non-nil if a password is required when connecting to POP server.")
  51 (defvar pop3-password nil
  52   "*Password to use when connecting to POP server.")
  53
  54 (defvar pop3-authentication-scheme 'pass
  55   "*POP3 authentication scheme.
  56 Defaults to 'pass, for the standard USER/PASS authentication.  Other valid
  57 values are 'apop.")
  58
  59 (defvar pop3-timestamp nil
  60   "Timestamp returned when initially connected to the POP server.
  61 Used for APOP authentication.")
  62
  63 (defvar pop3-movemail-file-coding-system nil
  64   "Crashbox made by pop3-movemail with this coding system.")
  65
  66 (defvar pop3-read-point nil)
  67 (defvar pop3-debug nil)
  68
  69 (defun pop3-movemail (&optional crashbox)
  70   "Transfer contents of a maildrop to the specified CRASHBOX."
  71   (or crashbox (setq crashbox (expand-file-name "~/.crashbox")))
  72   (let* ((process (pop3-open-server pop3-mailhost pop3-port))
  73          (crashbuf (get-buffer-create " *pop3-retr*"))
  74          (n 1)
  75          message-count
  76          (pop3-password pop3-password)
  77          )
  78     ;; for debugging only
  79     (if pop3-debug (switch-to-buffer (process-buffer process)))
  80     ;; query for password
  81     (if (and pop3-password-required (not pop3-password))
  82         (setq pop3-password
  83               (pop3-read-passwd (format "Password for %s: " pop3-maildrop))))
  84     (cond ((equal 'apop pop3-authentication-scheme)
  85            (pop3-apop process pop3-maildrop))
  86           ((equal 'pass pop3-authentication-scheme)
  87            (pop3-user process pop3-maildrop)
  88            (pop3-pass process))
  89           (t (error "Invalid POP3 authentication scheme.")))
  90     (setq message-count (car (pop3-stat process)))
  91     (while (<= n message-count)
  92       (message (format "Retrieving message %d of %d from %s..."
  93                        n message-count pop3-mailhost))
  94       (pop3-retr process n crashbuf)
  95       (save-excursion
  96         (set-buffer crashbuf)
  97         (let ((coding-system-for-write pop3-movemail-file-coding-system))
  98           (append-to-file (point-min) (point-max) crashbox))
  99         (set-buffer (process-buffer process))
 100         (while (> (buffer-size) 5000)
 101           (goto-char (point-min))
 102           (forward-line 50)
 103           (delete-region (point-min) (point))))
 104       (pop3-dele process n)
 105       (setq n (+ 1 n))
 106       (if pop3-debug (sit-for 1) (sit-for 0.1))
 107       )
 108     (pop3-quit process)
 109     (kill-buffer crashbuf)
 110     )
 111   )
 112
 113 (defun pop3-open-server (mailhost port)
 114   "Open TCP connection to MAILHOST.
 115 Returns the process associated with the connection."
 116   (let ((process-buffer
 117          (get-buffer-create (format "trace of POP session to %s" mailhost)))
 118         (process)
 119         (coding-system-for-read 'binary)
 120         (coding-system-for-write 'binary)
 121     )
 122     (save-excursion
 123       (set-buffer process-buffer)
 124       (erase-buffer)
 125       (setq pop3-read-point (point-min))
 126       )
 127     (setq process
 128           (open-network-stream "POP" process-buffer mailhost port))
 129     (let ((response (pop3-read-response process t)))
 130       (setq pop3-timestamp
 131             (substring response (or (string-match "<" response) 0)
 132                        (+ 1 (or (string-match ">" response) -1)))))
 133     process
 134     ))
 135
 136 ;; Support functions
 137
 138 (defun pop3-process-filter (process output)
 139   (save-excursion
 140     (set-buffer (process-buffer process))
 141     (goto-char (point-max))
 142     (insert output)))
 143
 144 (defun pop3-send-command (process command)
 145     (set-buffer (process-buffer process))
 146     (goto-char (point-max))
 147 ;;    (if (= (aref command 0) ?P)
 148 ;;      (insert "PASS <omitted>\r\n")
 149 ;;      (insert command "\r\n"))
 150     (setq pop3-read-point (point))
 151     (goto-char (point-max))
 152     (process-send-string process command)
 153     (process-send-string process "\r\n")
 154     )
 155
 156 (defun pop3-read-response (process &optional return)
 157   "Read the response from the server.
 158 Return the response string if optional second argument is non-nil."
 159   (let ((case-fold-search nil)
 160         match-end)
 161     (save-excursion
 162       (set-buffer (process-buffer process))
 163       (goto-char pop3-read-point)
 164       (while (not (search-forward "\r\n" nil t))
 165         (accept-process-output process 3)
 166         (goto-char pop3-read-point))
 167       (setq match-end (point))
 168       (goto-char pop3-read-point)
 169       (if (looking-at "-ERR")
 170           (error (buffer-substring (point) (- match-end 2)))
 171         (if (not (looking-at "+OK"))
 172             (progn (setq pop3-read-point match-end) nil)
 173           (setq pop3-read-point match-end)
 174           (if return
 175               (buffer-substring (point) match-end)
 176             t)
 177           )))))
 178
 179 (defun pop3-string-to-list (string &optional regexp)
 180   "Chop up a string into a list."
 181   (let ((list)
 182         (regexp (or regexp " "))
 183         (string (if (string-match "\r" string)
 184                     (substring string 0 (match-beginning 0))
 185                   string)))
 186     (store-match-data nil)
 187     (while string
 188       (if (string-match regexp string)
 189           (setq list (cons (substring string 0 (- (match-end 0) 1)) list)
 190                 string (substring string (match-end 0)))
 191         (setq list (cons string list)
 192               string nil)))
 193     (nreverse list)))
 194
 195 (defvar pop3-read-passwd nil)
 196 (defun pop3-read-passwd (prompt)
 197   (if (not pop3-read-passwd)
 198       (if (fboundp 'read-passwd)
 199           (setq pop3-read-passwd 'read-passwd)
 200         (if (load "passwd" t)
 201             (setq pop3-read-passwd 'read-passwd)
 202           (autoload 'ange-ftp-read-passwd "ange-ftp")
 203           (setq pop3-read-passwd 'ange-ftp-read-passwd))))
 204   (funcall pop3-read-passwd prompt))
 205
 206 (defun pop3-clean-region (start end)
 207   (setq end (set-marker (make-marker) end))
 208   (save-excursion
 209     (goto-char start)
 210     (while (and (< (point) end) (search-forward "\r\n" end t))
 211       (replace-match "\n" t t))
 212     (goto-char start)
 213     (while (and (< (point) end) (re-search-forward "^\\." end t))
 214       (replace-match "" t t)
 215       (forward-char)))
 216   (set-marker end nil))
 217
 218 (defun pop3-munge-message-separator (start end)
 219   "Check to see if a message separator exists.  If not, generate one."
 220   (if (not (fboundp 'message-make-date)) (autoload 'message-make-date "message"))
 221   (save-excursion
 222     (save-restriction
 223       (narrow-to-region start end)
 224       (goto-char (point-min))
 225       (if (not (or (looking-at "From .?") ; Unix mail
 226                    (looking-at "\001\001\001\001\n") ; MMDF
 227                    (looking-at "BABYL OPTIONS:") ; Babyl
 228                    ))
 229           (let ((from (mail-strip-quoted-names (mail-fetch-field "From")))
 230                 (date (pop3-string-to-list (or (mail-fetch-field "Date")
 231                                                (message-make-date))))
 232                 (From_))
 233             ;; sample date formats I have seen
 234             ;; Date: Tue, 9 Jul 1996 09:04:21 -0400 (EDT)
 235             ;; Date: 08 Jul 1996 23:22:24 -0400
 236             ;; should be
 237             ;; Tue Jul 9 09:04:21 1996
 238             (setq date
 239                   (cond ((string-match "[A-Z]" (nth 0 date))
 240                          (format "%s %s %s %s %s"
 241                                  (nth 0 date) (nth 2 date) (nth 1 date)
 242                                  (nth 4 date) (nth 3 date)))
 243                         (t
 244                          ;; this really needs to be better but I don't feel
 245                          ;; like writing a date to day converter.
 246                          (format "Sun %s %s %s %s"
 247                                  (nth 1 date) (nth 0 date)
 248                                  (nth 3 date) (nth 2 date)))
 249                         ))
 250             (setq From_ (format "\nFrom %s  %s\n" from date))
 251             (while (string-match "," From_)
 252               (setq From_ (concat (substring From_ 0 (match-beginning 0))
 253                                   (substring From_ (match-end 0)))))
 254             (goto-char (point-min))
 255             (insert From_))))))
 256
 257 ;; The Command Set
 258
 259 ;; AUTHORIZATION STATE
 260
 261 (defun pop3-user (process user)
 262   "Send USER information to POP3 server."
 263   (pop3-send-command process (format "USER %s" user))
 264   (let ((response (pop3-read-response process t)))
 265     (if (not (and response (string-match "+OK" response)))
 266         (error (format "USER %s not valid." user)))))
 267
 268 (defun pop3-pass (process)
 269   "Send authentication information to the server."
 270   (pop3-send-command process (format "PASS %s" pop3-password))
 271   (let ((response (pop3-read-response process t)))
 272     (if (not (and response (string-match "+OK" response)))
 273         (pop3-quit process))))
 274
 275 (defun pop3-apop (process user)
 276   "Send alternate authentication information to the server."
 277   (let ((pass pop3-password))
 278     (if (and pop3-password-required (not pass))
 279         (setq pass
 280               (pop3-read-passwd (format "Password for %s: " pop3-maildrop))))
 281     (if pass
 282         (let ((hash (pop3-md5 (concat pop3-timestamp pass))))
 283           (pop3-send-command process (format "APOP %s %s" user hash))
 284           (let ((response (pop3-read-response process t)))
 285             (if (not (and response (string-match "+OK" response)))
 286                 (pop3-quit process)))))
 287     ))
 288
 289 ;; TRANSACTION STATE
 290
 291 (defvar pop3-md5-program "md5"
 292   "*Program to encode its input in MD5.")
 293
 294 (defun pop3-md5 (string)
 295   (with-temp-buffer
 296     (insert string)
 297     (call-process-region (point-min) (point-max)
 298                          (or shell-file-name "/bin/sh")
 299                          t (current-buffer) nil
 300                          "-c" pop3-md5-program)
 301     ;; The meaningful output is the first 32 characters.
 302     ;; Don't return the newline that follows them!
 303     (buffer-substring (point-min) (+ (point-min) 32))))
 304
 305 (defun pop3-stat (process)
 306   "Return the number of messages in the maildrop and the maildrop's size."
 307   (pop3-send-command process "STAT")
 308   (let ((response (pop3-read-response process t)))
 309     (list (string-to-int (nth 1 (pop3-string-to-list response)))
 310           (string-to-int (nth 2 (pop3-string-to-list response))))
 311     ))
 312
 313 (defun pop3-list (process &optional msg)
 314   "Scan listing of available messages.
 315 This function currently does nothing.")
 316
 317 (defun pop3-retr (process msg crashbuf)
 318   "Retrieve message-id MSG to buffer CRASHBUF."
 319   (pop3-send-command process (format "RETR %s" msg))
 320   (pop3-read-response process)
 321   (let ((start pop3-read-point) end)
 322     (save-excursion
 323       (set-buffer (process-buffer process))
 324       (while (not (re-search-forward "^\\.\r\n" nil t))
 325         (accept-process-output process 3)
 326         ;; bill@att.com ... to save wear and tear on the heap
 327         ;; uncommented because the condensed version below is a problem for
 328         ;; some.
 329         (if (> (buffer-size)  20000) (sleep-for 1))
 330         (if (> (buffer-size)  50000) (sleep-for 1))
 331         (if (> (buffer-size) 100000) (sleep-for 1))
 332         (if (> (buffer-size) 200000) (sleep-for 1))
 333         (if (> (buffer-size) 500000) (sleep-for 1))
 334         ;; bill@att.com
 335         ;; condensed into:
 336         ;; (sometimes causes problems for really large messages.)
 337 ;       (if (> (buffer-size) 20000) (sleep-for (/ (buffer-size) 20000)))
 338         (goto-char start))
 339       (setq pop3-read-point (point-marker))
 340 ;; this code does not seem to work for some POP servers...
 341 ;; and I cannot figure out why not.
 342 ;      (goto-char (match-beginning 0))
 343 ;      (backward-char 2)
 344 ;      (if (not (looking-at "\r\n"))
 345 ;         (insert "\r\n"))
 346 ;      (re-search-forward "\\.\r\n")
 347       (goto-char (match-beginning 0))
 348       (setq end (point-marker))
 349       (pop3-clean-region start end)
 350       (pop3-munge-message-separator start end)
 351       (save-excursion
 352         (set-buffer crashbuf)
 353         (erase-buffer))
 354       (copy-to-buffer crashbuf start end)
 355       (delete-region start end)
 356       )))
 357
 358 (defun pop3-dele (process msg)
 359   "Mark message-id MSG as deleted."
 360   (pop3-send-command process (format "DELE %s" msg))
 361   (pop3-read-response process))
 362
 363 (defun pop3-noop (process msg)
 364   "No-operation."
 365   (pop3-send-command process "NOOP")
 366   (pop3-read-response process))
 367
 368 (defun pop3-last (process)
 369   "Return highest accessed message-id number for the session."
 370   (pop3-send-command process "LAST")
 371   (let ((response (pop3-read-response process t)))
 372     (string-to-int (nth 1 (pop3-string-to-list response)))
 373     ))
 374
 375 (defun pop3-rset (process)
 376   "Remove all delete marks from current maildrop."
 377   (pop3-send-command process "RSET")
 378   (pop3-read-response process))
 379
 380 ;; UPDATE
 381
 382 (defun pop3-quit (process)
 383   "Close connection to POP3 server.
 384 Tell server to remove all messages marked as deleted, unlock the maildrop,
 385 and close the connection."
 386   (pop3-send-command process "QUIT")
 387   (pop3-read-response process t)
 388   (if process
 389       (save-excursion
 390         (set-buffer (process-buffer process))
 391         (goto-char (point-max))
 392         (delete-process process))))
 393 \f
 394 ;; Summary of POP3 (Post Office Protocol version 3) commands and responses
 395
 396 ;;; AUTHORIZATION STATE
 397
 398 ;; Initial TCP connection
 399 ;; Arguments: none
 400 ;; Restrictions: none
 401 ;; Possible responses:
 402 ;;  +OK [POP3 server ready]
 403
 404 ;; USER name
 405 ;; Arguments: a server specific user-id (required)
 406 ;; Restrictions: authorization state [after unsuccessful USER or PASS
 407 ;; Possible responses:
 408 ;;  +OK [valid user-id]
 409 ;;  -ERR [invalid user-id]
 410
 411 ;; PASS string
 412 ;; Arguments: a server/user-id specific password (required)
 413 ;; Restrictions: authorization state, after successful USER
 414 ;; Possible responses:
 415 ;;  +OK [maildrop locked and ready]
 416 ;;  -ERR [invalid password]
 417 ;;  -ERR [unable to lock maildrop]
 418
 419 ;;; TRANSACTION STATE
 420
 421 ;; STAT
 422 ;; Arguments: none
 423 ;; Restrictions: transaction state
 424 ;; Possible responses:
 425 ;;  +OK nn mm [# of messages, size of maildrop]
 426
 427 ;; LIST [msg]
 428 ;; Arguments: a message-id (optional)
 429 ;; Restrictions: transaction state; msg must not be deleted
 430 ;; Possible responses:
 431 ;;  +OK [scan listing follows]
 432 ;;  -ERR [no such message]
 433
 434 ;; RETR msg
 435 ;; Arguments: a message-id (required)
 436 ;; Restrictions: transaction state; msg must not be deleted
 437 ;; Possible responses:
 438 ;;  +OK [message contents follow]
 439 ;;  -ERR [no such message]
 440
 441 ;; DELE msg
 442 ;; Arguments: a message-id (required)
 443 ;; Restrictions: transaction state; msg must not be deleted
 444 ;; Possible responses:
 445 ;;  +OK [message deleted]
 446 ;;  -ERR [no such message]
 447
 448 ;; NOOP
 449 ;; Arguments: none
 450 ;; Restrictions: transaction state
 451 ;; Possible responses:
 452 ;;  +OK
 453
 454 ;; LAST
 455 ;; Arguments: none
 456 ;; Restrictions: transaction state
 457 ;; Possible responses:
 458 ;;  +OK nn [highest numbered message accessed]
 459
 460 ;; RSET
 461 ;; Arguments: none
 462 ;; Restrictions: transaction state
 463 ;; Possible responses:
 464 ;;  +OK [all delete marks removed]
 465
 466 ;;; UPDATE STATE
 467
 468 ;; QUIT
 469 ;; Arguments: none
 470 ;; Restrictions: none
 471 ;; Possible responses:
 472 ;;  +OK [TCP connection closed]