lisp/url/url-cookie.el

   1 ;;; url-cookie.el --- Netscape Cookie support
   2
   3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2004,
   4 ;;   2005, 2006, 2007 Free Software Foundation, Inc.
   5
   6 ;; Keywords: comm, data, processes, hypermedia
   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 3, 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 ;;; Commentary:
  26
  27 ;;; Code:
  28
  29 (require 'timezone)
  30 (require 'url-util)
  31 (require 'url-parse)
  32 (eval-when-compile (require 'cl))
  33
  34 ;; See http://home.netscape.com/newsref/std/cookie_spec.html for the
  35 ;; 'open standard' defining this crap.
  36
  37 (defgroup url-cookie nil
  38   "URL cookies."
  39   :prefix "url-"
  40   :prefix "url-cookie-"
  41   :group 'url)
  42
  43 ;; A cookie is stored internally as a vector of 7 slots
  44 ;; [ cookie NAME VALUE EXPIRES LOCALPART DOMAIN SECURE ]
  45
  46 (defstruct (url-cookie
  47             (:constructor url-cookie-create)
  48             (:copier nil)
  49             ;; For compatibility with a previous version which did not use
  50             ;; defstruct, and also in order to make sure that the printed
  51             ;; representation does not depend on CL internals, we use an
  52             ;; explicitly managed tag.
  53             (:type vector))
  54   (tag 'cookie :read-only t)
  55   name value expires localpart domain secure)
  56
  57 (defvar url-cookie-storage nil         "Where cookies are stored.")
  58 (defvar url-cookie-secure-storage nil  "Where secure cookies are stored.")
  59 (defcustom url-cookie-file nil
  60   "File where cookies are stored on disk."
  61   :type '(choice (const :tag "Default" :value nil) file)
  62   :group 'url-file
  63   :group 'url-cookie)
  64
  65 (defcustom url-cookie-confirmation nil
  66   "If non-nil, confirmation by the user is required to accept HTTP cookies."
  67   :type 'boolean
  68   :group 'url-cookie)
  69
  70 (defcustom url-cookie-multiple-line nil
  71   "If nil, HTTP requests put all cookies for the server on one line.
  72 Some web servers, such as http://www.hotmail.com/, only accept cookies
  73 when they are on one line.  This is broken behavior, but just try
  74 telling Microsoft that."
  75   :type 'boolean
  76   :group 'url-cookie)
  77
  78 (defvar url-cookies-changed-since-last-save nil
  79   "Whether the cookies list has changed since the last save operation.")
  80
  81 (defun url-cookie-parse-file (&optional fname)
  82   (setq fname (or fname url-cookie-file))
  83   (condition-case ()
  84       (load fname nil t)
  85     (error
  86      ;; It's completely normal for the cookies file not to exist yet.
  87      ;; (message "Could not load cookie file %s" fname)
  88      )))
  89
  90 (declare-function url-cookie-p "url-cookie" t t) ; defstruct
  91
  92 (defun url-cookie-clean-up (&optional secure)
  93   (let* (
  94          (var (if secure 'url-cookie-secure-storage 'url-cookie-storage))
  95          (val (symbol-value var))
  96          (cur nil)
  97          (new nil)
  98          (cookies nil)
  99          (cur-cookie nil)
 100          (new-cookies nil)
 101          )
 102     (while val
 103       (setq cur (car val)
 104             val (cdr val)
 105             new-cookies nil
 106             cookies (cdr cur))
 107       (while cookies
 108         (setq cur-cookie (car cookies)
 109               cookies (cdr cookies))
 110         (if (or (not (url-cookie-p cur-cookie))
 111                 (url-cookie-expired-p cur-cookie)
 112                 (null (url-cookie-expires cur-cookie)))
 113             nil
 114           (setq new-cookies (cons cur-cookie new-cookies))))
 115       (if (not new-cookies)
 116           nil
 117         (setcdr cur new-cookies)
 118         (setq new (cons cur new))))
 119     (set var new)))
 120
 121 (defun url-cookie-write-file (&optional fname)
 122   (setq fname (or fname url-cookie-file))
 123   (unless (file-directory-p (file-name-directory fname))
 124     (ignore-errors (make-directory (file-name-directory fname))))
 125   (cond
 126    ((not url-cookies-changed-since-last-save) nil)
 127    ((not (file-writable-p fname))
 128     (message "Cookies file %s (see variable `url-cookie-file') is unwritable." fname))
 129    (t
 130     (url-cookie-clean-up)
 131     (url-cookie-clean-up t)
 132     (with-current-buffer (get-buffer-create " *cookies*")
 133       (erase-buffer)
 134       (fundamental-mode)
 135       (insert ";; Emacs-W3 HTTP cookies file\n"
 136               ";; Automatically generated file!!! DO NOT EDIT!!!\n\n"
 137               "(setq url-cookie-storage\n '")
 138       (pp url-cookie-storage (current-buffer))
 139       (insert ")\n(setq url-cookie-secure-storage\n '")
 140       (pp url-cookie-secure-storage (current-buffer))
 141       (insert ")\n")
 142       (insert "\f\n;; Local Variables:\n"
 143               ";; version-control: never\n"
 144               ";; no-byte-compile: t\n"
 145               ";; End:\n")
 146       (set (make-local-variable 'version-control) 'never)
 147       (write-file fname)
 148       (setq url-cookies-changed-since-last-save nil)
 149       (kill-buffer (current-buffer))))))
 150
 151 (defun url-cookie-store (name value &optional expires domain localpart secure)
 152   "Store a netscape-style cookie."
 153   (let* ((storage (if secure url-cookie-secure-storage url-cookie-storage))
 154          (tmp storage)
 155          (cur nil)
 156          (found-domain nil))
 157
 158     ;; First, look for a matching domain
 159     (setq found-domain (assoc domain storage))
 160
 161     (if found-domain
 162         ;; Need to either stick the new cookie in existing domain storage
 163         ;; or possibly replace an existing cookie if the names match.
 164         (progn
 165           (setq storage (cdr found-domain)
 166                 tmp nil)
 167           (while storage
 168             (setq cur (car storage)
 169                   storage (cdr storage))
 170             (if (and (equal localpart (url-cookie-localpart cur))
 171                      (equal name (url-cookie-name cur)))
 172                 (progn
 173                   (setf (url-cookie-expires cur) expires)
 174                   (setf (url-cookie-value cur) value)
 175                   (setq tmp t))))
 176           (if (not tmp)
 177               ;; New cookie
 178               (setcdr found-domain (cons
 179                                     (url-cookie-create :name name
 180                                                        :value value
 181                                                        :expires expires
 182                                                        :domain domain
 183                                                        :localpart localpart
 184                                                        :secure secure)
 185                                     (cdr found-domain)))))
 186       ;; Need to add a new top-level domain
 187       (setq tmp (url-cookie-create :name name
 188                                    :value value
 189                                    :expires expires
 190                                    :domain domain
 191                                    :localpart localpart
 192                                    :secure secure))
 193       (cond
 194        (storage
 195         (setcdr storage (cons (list domain tmp) (cdr storage))))
 196        (secure
 197         (setq url-cookie-secure-storage (list (list domain tmp))))
 198        (t
 199         (setq url-cookie-storage (list (list domain tmp))))))))
 200
 201 (defun url-cookie-expired-p (cookie)
 202   (let* (
 203          (exp (url-cookie-expires cookie))
 204          (cur-date (and exp (timezone-parse-date (current-time-string))))
 205          (exp-date (and exp (timezone-parse-date exp)))
 206          (cur-greg (and cur-date (timezone-absolute-from-gregorian
 207                                   (string-to-number (aref cur-date 1))
 208                                   (string-to-number (aref cur-date 2))
 209                                   (string-to-number (aref cur-date 0)))))
 210          (exp-greg (and exp (timezone-absolute-from-gregorian
 211                              (string-to-number (aref exp-date 1))
 212                              (string-to-number (aref exp-date 2))
 213                              (string-to-number (aref exp-date 0)))))
 214          (diff-in-days (and exp (- cur-greg exp-greg)))
 215          )
 216     (cond
 217      ((not exp) nil)                    ; No expiry == expires at browser quit
 218      ((< diff-in-days 0) nil)           ; Expires sometime after today
 219      ((> diff-in-days 0) t)             ; Expired before today
 220      (t                                 ; Expires sometime today, check times
 221       (let* ((cur-time (timezone-parse-time (aref cur-date 3)))
 222              (exp-time (timezone-parse-time (aref exp-date 3)))
 223              (cur-norm (+ (* 360 (string-to-number (aref cur-time 2)))
 224                           (*  60 (string-to-number (aref cur-time 1)))
 225                           (*   1 (string-to-number (aref cur-time 0)))))
 226              (exp-norm (+ (* 360 (string-to-number (aref exp-time 2)))
 227                           (*  60 (string-to-number (aref exp-time 1)))
 228                           (*   1 (string-to-number (aref exp-time 0))))))
 229         (> (- cur-norm exp-norm) 1))))))
 230
 231 (defun url-cookie-retrieve (host localpart &optional secure)
 232   "Retrieve all the netscape-style cookies for a specified HOST and LOCALPART."
 233   (let ((storage (if secure
 234                      (append url-cookie-secure-storage url-cookie-storage)
 235                    url-cookie-storage))
 236         (case-fold-search t)
 237         (cookies nil)
 238         (cur nil)
 239         (retval nil)
 240         (localpart-regexp nil))
 241     (while storage
 242       (setq cur (car storage)
 243             storage (cdr storage)
 244             cookies (cdr cur))
 245       (if (and (car cur)
 246                (string-match
 247                 (concat "^.*"
 248                         (regexp-quote
 249                          ;; Remove the dot from wildcard domains
 250                          ;; before matching.
 251                          (if (eq ?. (aref (car cur) 0))
 252                              (substring (car cur) 1)
 253                            (car cur)))
 254                         "$") host))
 255           ;; The domains match - a possible hit!
 256           (while cookies
 257             (setq cur (car cookies)
 258                   cookies (cdr cookies)
 259                   localpart-regexp (concat "^" (regexp-quote
 260                                                 (url-cookie-localpart cur))))
 261             (if (and (string-match localpart-regexp localpart)
 262                      (not (url-cookie-expired-p cur)))
 263                 (setq retval (cons cur retval))))))
 264     retval))
 265
 266 (defun url-cookie-generate-header-lines (host localpart secure)
 267   (let* ((cookies (url-cookie-retrieve host localpart secure))
 268          (retval nil)
 269          (cur nil)
 270          (chunk nil))
 271     ;; Have to sort this for sending most specific cookies first
 272     (setq cookies (and cookies
 273                        (sort cookies
 274                              (function
 275                               (lambda (x y)
 276                                 (> (length (url-cookie-localpart x))
 277                                    (length (url-cookie-localpart y))))))))
 278     (while cookies
 279       (setq cur (car cookies)
 280             cookies (cdr cookies)
 281             chunk (format "%s=%s" (url-cookie-name cur) (url-cookie-value cur))
 282             retval (if (and url-cookie-multiple-line
 283                             (< 80 (+ (length retval) (length chunk) 4)))
 284                        (concat retval "\r\nCookie: " chunk)
 285                      (if retval
 286                          (concat retval "; " chunk)
 287                        (concat "Cookie: " chunk)))))
 288     (if retval
 289         (concat retval "\r\n")
 290       "")))
 291
 292 (defvar url-cookie-two-dot-domains
 293   (concat "\\.\\("
 294    (mapconcat 'identity (list "com" "edu" "net" "org" "gov" "mil" "int")
 295               "\\|")
 296    "\\)$")
 297   "A regexp of top level domains that only require two matching
 298 '.'s in the domain name in order to set a cookie.")
 299
 300 (defcustom url-cookie-trusted-urls nil
 301   "A list of regular expressions matching URLs to always accept cookies from."
 302   :type '(repeat regexp)
 303   :group 'url-cookie)
 304
 305 (defcustom url-cookie-untrusted-urls nil
 306   "A list of regular expressions matching URLs to never accept cookies from."
 307   :type '(repeat regexp)
 308   :group 'url-cookie)
 309
 310 (defun url-cookie-host-can-set-p (host domain)
 311   (let ((numdots 0)
 312         (last nil)
 313         (case-fold-search t)
 314         (mindots 3))
 315     (while (setq last (string-match "\\." domain last))
 316       (setq numdots (1+ numdots)
 317             last (1+ last)))
 318     (if (string-match url-cookie-two-dot-domains domain)
 319         (setq mindots 2))
 320     (cond
 321      ((string= host domain)             ; Apparently netscape lets you do this
 322       t)
 323      ((>= numdots mindots)              ; We have enough dots in domain name
 324       ;; Need to check and make sure the host is actually _in_ the
 325       ;; domain it wants to set a cookie for though.
 326       (string-match (concat (regexp-quote
 327                              ;; Remove the dot from wildcard domains
 328                              ;; before matching.
 329                              (if (eq ?. (aref domain 0))
 330                                  (substring domain 1)
 331                                domain))
 332                             "$") host))
 333      (t
 334       nil))))
 335
 336 (defun url-cookie-handle-set-cookie (str)
 337   (setq url-cookies-changed-since-last-save t)
 338   (let* ((args (url-parse-args str t))
 339          (case-fold-search t)
 340          (secure (and (assoc-string "secure" args t) t))
 341          (domain (or (cdr-safe (assoc-string "domain" args t))
 342                      (url-host url-current-object)))
 343          (current-url (url-view-url t))
 344          (trusted url-cookie-trusted-urls)
 345          (untrusted url-cookie-untrusted-urls)
 346          (expires (cdr-safe (assoc-string "expires" args t)))
 347          (localpart (or (cdr-safe (assoc-string "path" args t))
 348                         (file-name-directory
 349                          (url-filename url-current-object))))
 350          (rest nil))
 351     (while args
 352       (if (not (member (downcase (car (car args)))
 353                        '("secure" "domain" "expires" "path")))
 354           (setq rest (cons (car args) rest)))
 355       (setq args (cdr args)))
 356
 357     ;; Sometimes we get dates that the timezone package cannot handle very
 358     ;; gracefully - take care of this here, instead of in url-cookie-expired-p
 359     ;; to speed things up.
 360     (if (and expires
 361              (string-match
 362               (concat "^[^,]+, +\\(..\\)-\\(...\\)-\\(..\\) +"
 363                       "\\(..:..:..\\) +\\[*\\([^\]]+\\)\\]*$")
 364               expires))
 365         (setq expires (concat (match-string 1 expires) " "
 366                               (match-string 2 expires) " "
 367                               (match-string 3 expires) " "
 368                               (match-string 4 expires) " ["
 369                               (match-string 5 expires) "]")))
 370
 371     ;; This one is for older Emacs/XEmacs variants that don't
 372     ;; understand this format without tenths of a second in it.
 373     ;; Wednesday, 30-Dec-2037 16:00:00 GMT
 374     ;;       - vs -
 375     ;; Wednesday, 30-Dec-2037 16:00:00.00 GMT
 376     (if (and expires
 377              (string-match
 378               "\\([0-9]+\\)-\\([A-Za-z]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)\\(\\.[0-9]+\\)*[ \t]+\\([-+a-zA-Z0-9]+\\)"
 379               expires))
 380         (setq expires (concat (match-string 1 expires) "-"      ; day
 381                               (match-string 2 expires) "-"      ; month
 382                               (match-string 3 expires) " "      ; year
 383                               (match-string 4 expires) ".00 " ; hour:minutes:seconds
 384                               (match-string 6 expires)))) ":" ; timezone
 385
 386     (while (consp trusted)
 387       (if (string-match (car trusted) current-url)
 388           (setq trusted (- (match-end 0) (match-beginning 0)))
 389         (pop trusted)))
 390     (while (consp untrusted)
 391       (if (string-match (car untrusted) current-url)
 392           (setq untrusted (- (match-end 0) (match-beginning 0)))
 393         (pop untrusted)))
 394     (if (and trusted untrusted)
 395         ;; Choose the more specific match
 396         (if (> trusted untrusted)
 397             (setq untrusted nil)
 398           (setq trusted nil)))
 399     (cond
 400      (untrusted
 401       ;; The site was explicity marked as untrusted by the user
 402       nil)
 403      ((or (eq url-privacy-level 'paranoid)
 404           (and (listp url-privacy-level) (memq 'cookies url-privacy-level)))
 405       ;; user never wants cookies
 406       nil)
 407      ((and url-cookie-confirmation
 408            (not trusted)
 409            (save-window-excursion
 410              (with-output-to-temp-buffer "*Cookie Warning*"
 411                (mapcar
 412                 (function
 413                  (lambda (x)
 414                    (princ (format "%s - %s" (car x) (cdr x))))) rest))
 415              (prog1
 416                  (not (funcall url-confirmation-func
 417                                (format "Allow %s to set these cookies? "
 418                                        (url-host url-current-object))))
 419                (if (get-buffer "*Cookie Warning*")
 420                    (kill-buffer "*Cookie Warning*")))))
 421       ;; user wants to be asked, and declined.
 422       nil)
 423      ((url-cookie-host-can-set-p (url-host url-current-object) domain)
 424       ;; Cookie is accepted by the user, and passes our security checks
 425       (let ((cur nil))
 426         (while rest
 427           (setq cur (pop rest))
 428           (url-cookie-store (car cur) (cdr cur)
 429                             expires domain localpart secure))))
 430      (t
 431       (message "%s tried to set a cookie for domain %s - rejected."
 432                (url-host url-current-object) domain)))))
 433
 434 (defvar url-cookie-timer nil)
 435
 436 (defcustom url-cookie-save-interval 3600
 437   "The number of seconds between automatic saves of cookies.
 438 Default is 1 hour.  Note that if you change this variable outside of
 439 the `customize' interface after `url-do-setup' has been run, you need
 440 to run the `url-cookie-setup-save-timer' function manually."
 441   :set #'(lambda (var val)
 442            (set-default var val)
 443            (if (bound-and-true-p url-setup-done)
 444                (url-cookie-setup-save-timer)))
 445   :type 'integer
 446   :group 'url-cookie)
 447
 448 (defun url-cookie-setup-save-timer ()
 449   "Reset the cookie saver timer."
 450   (interactive)
 451   (ignore-errors (cancel-timer url-cookie-timer))
 452   (setq url-cookie-timer nil)
 453   (if url-cookie-save-interval
 454       (setq url-cookie-timer (run-at-time url-cookie-save-interval
 455                                           url-cookie-save-interval
 456                                           #'url-cookie-write-file))))
 457
 458 (provide 'url-cookie)
 459
 460 ;; arch-tag: 2568751b-6452-4398-aa2d-303edadb54d7
 461 ;;; url-cookie.el ends here