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, 2008 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   (when url-cookies-changed-since-last-save
 123     (or fname (setq fname (expand-file-name url-cookie-file)))
 124     (if (condition-case nil
 125             (progn
 126               (url-make-private-file fname)
 127               nil)
 128           (error t))
 129         (message "Error accessing cookie file `%s'" fname)
 130     (url-cookie-clean-up)
 131     (url-cookie-clean-up t)
 132     (with-temp-buffer
 133       (insert ";; Emacs-W3 HTTP cookies file\n"
 134               ";; Automatically generated file!!! DO NOT EDIT!!!\n\n"
 135               "(setq url-cookie-storage\n '")
 136       (pp url-cookie-storage (current-buffer))
 137       (insert ")\n(setq url-cookie-secure-storage\n '")
 138       (pp url-cookie-secure-storage (current-buffer))
 139       (insert ")\n")
 140       (insert "\f\n;; Local Variables:\n"
 141               ";; version-control: never\n"
 142               ";; no-byte-compile: t\n"
 143               ";; End:\n")
 144       (set (make-local-variable 'version-control) 'never)
 145       (write-file fname))
 146     (setq url-cookies-changed-since-last-save nil))))
 147
 148 (defun url-cookie-store (name value &optional expires domain localpart secure)
 149   "Store a netscape-style cookie."
 150   (let* ((storage (if secure url-cookie-secure-storage url-cookie-storage))
 151          (tmp storage)
 152          (cur nil)
 153          (found-domain nil))
 154
 155     ;; First, look for a matching domain
 156     (setq found-domain (assoc domain storage))
 157
 158     (if found-domain
 159         ;; Need to either stick the new cookie in existing domain storage
 160         ;; or possibly replace an existing cookie if the names match.
 161         (progn
 162           (setq storage (cdr found-domain)
 163                 tmp nil)
 164           (while storage
 165             (setq cur (car storage)
 166                   storage (cdr storage))
 167             (if (and (equal localpart (url-cookie-localpart cur))
 168                      (equal name (url-cookie-name cur)))
 169                 (progn
 170                   (setf (url-cookie-expires cur) expires)
 171                   (setf (url-cookie-value cur) value)
 172                   (setq tmp t))))
 173           (if (not tmp)
 174               ;; New cookie
 175               (setcdr found-domain (cons
 176                                     (url-cookie-create :name name
 177                                                        :value value
 178                                                        :expires expires
 179                                                        :domain domain
 180                                                        :localpart localpart
 181                                                        :secure secure)
 182                                     (cdr found-domain)))))
 183       ;; Need to add a new top-level domain
 184       (setq tmp (url-cookie-create :name name
 185                                    :value value
 186                                    :expires expires
 187                                    :domain domain
 188                                    :localpart localpart
 189                                    :secure secure))
 190       (cond
 191        (storage
 192         (setcdr storage (cons (list domain tmp) (cdr storage))))
 193        (secure
 194         (setq url-cookie-secure-storage (list (list domain tmp))))
 195        (t
 196         (setq url-cookie-storage (list (list domain tmp))))))))
 197
 198 (defun url-cookie-expired-p (cookie)
 199   (let* (
 200          (exp (url-cookie-expires cookie))
 201          (cur-date (and exp (timezone-parse-date (current-time-string))))
 202          (exp-date (and exp (timezone-parse-date exp)))
 203          (cur-greg (and cur-date (timezone-absolute-from-gregorian
 204                                   (string-to-number (aref cur-date 1))
 205                                   (string-to-number (aref cur-date 2))
 206                                   (string-to-number (aref cur-date 0)))))
 207          (exp-greg (and exp (timezone-absolute-from-gregorian
 208                              (string-to-number (aref exp-date 1))
 209                              (string-to-number (aref exp-date 2))
 210                              (string-to-number (aref exp-date 0)))))
 211          (diff-in-days (and exp (- cur-greg exp-greg)))
 212          )
 213     (cond
 214      ((not exp) nil)                    ; No expiry == expires at browser quit
 215      ((< diff-in-days 0) nil)           ; Expires sometime after today
 216      ((> diff-in-days 0) t)             ; Expired before today
 217      (t                                 ; Expires sometime today, check times
 218       (let* ((cur-time (timezone-parse-time (aref cur-date 3)))
 219              (exp-time (timezone-parse-time (aref exp-date 3)))
 220              (cur-norm (+ (* 360 (string-to-number (aref cur-time 2)))
 221                           (*  60 (string-to-number (aref cur-time 1)))
 222                           (*   1 (string-to-number (aref cur-time 0)))))
 223              (exp-norm (+ (* 360 (string-to-number (aref exp-time 2)))
 224                           (*  60 (string-to-number (aref exp-time 1)))
 225                           (*   1 (string-to-number (aref exp-time 0))))))
 226         (> (- cur-norm exp-norm) 1))))))
 227
 228 (defun url-cookie-retrieve (host localpart &optional secure)
 229   "Retrieve all the netscape-style cookies for a specified HOST and LOCALPART."
 230   (let ((storage (if secure
 231                      (append url-cookie-secure-storage url-cookie-storage)
 232                    url-cookie-storage))
 233         (case-fold-search t)
 234         (cookies nil)
 235         (cur nil)
 236         (retval nil)
 237         (localpart-regexp nil))
 238     (while storage
 239       (setq cur (car storage)
 240             storage (cdr storage)
 241             cookies (cdr cur))
 242       (if (and (car cur)
 243                (string-match
 244                 (concat "^.*"
 245                         (regexp-quote
 246                          ;; Remove the dot from wildcard domains
 247                          ;; before matching.
 248                          (if (eq ?. (aref (car cur) 0))
 249                              (substring (car cur) 1)
 250                            (car cur)))
 251                         "$") host))
 252           ;; The domains match - a possible hit!
 253           (while cookies
 254             (setq cur (car cookies)
 255                   cookies (cdr cookies)
 256                   localpart-regexp (concat "^" (regexp-quote
 257                                                 (url-cookie-localpart cur))))
 258             (if (and (string-match localpart-regexp localpart)
 259                      (not (url-cookie-expired-p cur)))
 260                 (setq retval (cons cur retval))))))
 261     retval))
 262
 263 (defun url-cookie-generate-header-lines (host localpart secure)
 264   (let* ((cookies (url-cookie-retrieve host localpart secure))
 265          (retval nil)
 266          (cur nil)
 267          (chunk nil))
 268     ;; Have to sort this for sending most specific cookies first
 269     (setq cookies (and cookies
 270                        (sort cookies
 271                              (function
 272                               (lambda (x y)
 273                                 (> (length (url-cookie-localpart x))
 274                                    (length (url-cookie-localpart y))))))))
 275     (while cookies
 276       (setq cur (car cookies)
 277             cookies (cdr cookies)
 278             chunk (format "%s=%s" (url-cookie-name cur) (url-cookie-value cur))
 279             retval (if (and url-cookie-multiple-line
 280                             (< 80 (+ (length retval) (length chunk) 4)))
 281                        (concat retval "\r\nCookie: " chunk)
 282                      (if retval
 283                          (concat retval "; " chunk)
 284                        (concat "Cookie: " chunk)))))
 285     (if retval
 286         (concat retval "\r\n")
 287       "")))
 288
 289 (defvar url-cookie-two-dot-domains
 290   (concat "\\.\\("
 291    (mapconcat 'identity (list "com" "edu" "net" "org" "gov" "mil" "int")
 292               "\\|")
 293    "\\)$")
 294   "A regexp of top level domains that only require two matching
 295 '.'s in the domain name in order to set a cookie.")
 296
 297 (defcustom url-cookie-trusted-urls nil
 298   "A list of regular expressions matching URLs to always accept cookies from."
 299   :type '(repeat regexp)
 300   :group 'url-cookie)
 301
 302 (defcustom url-cookie-untrusted-urls nil
 303   "A list of regular expressions matching URLs to never accept cookies from."
 304   :type '(repeat regexp)
 305   :group 'url-cookie)
 306
 307 (defun url-cookie-host-can-set-p (host domain)
 308   (let ((numdots 0)
 309         (last nil)
 310         (case-fold-search t)
 311         (mindots 3))
 312     (while (setq last (string-match "\\." domain last))
 313       (setq numdots (1+ numdots)
 314             last (1+ last)))
 315     (if (string-match url-cookie-two-dot-domains domain)
 316         (setq mindots 2))
 317     (cond
 318      ((string= host domain)             ; Apparently netscape lets you do this
 319       t)
 320      ((>= numdots mindots)              ; We have enough dots in domain name
 321       ;; Need to check and make sure the host is actually _in_ the
 322       ;; domain it wants to set a cookie for though.
 323       (string-match (concat (regexp-quote
 324                              ;; Remove the dot from wildcard domains
 325                              ;; before matching.
 326                              (if (eq ?. (aref domain 0))
 327                                  (substring domain 1)
 328                                domain))
 329                             "$") host))
 330      (t
 331       nil))))
 332
 333 (defun url-cookie-handle-set-cookie (str)
 334   (setq url-cookies-changed-since-last-save t)
 335   (let* ((args (url-parse-args str t))
 336          (case-fold-search t)
 337          (secure (and (assoc-string "secure" args t) t))
 338          (domain (or (cdr-safe (assoc-string "domain" args t))
 339                      (url-host url-current-object)))
 340          (current-url (url-view-url t))
 341          (trusted url-cookie-trusted-urls)
 342          (untrusted url-cookie-untrusted-urls)
 343          (expires (cdr-safe (assoc-string "expires" args t)))
 344          (localpart (or (cdr-safe (assoc-string "path" args t))
 345                         (file-name-directory
 346                          (url-filename url-current-object))))
 347          (rest nil))
 348     (while args
 349       (if (not (member (downcase (car (car args)))
 350                        '("secure" "domain" "expires" "path")))
 351           (setq rest (cons (car args) rest)))
 352       (setq args (cdr args)))
 353
 354     ;; Sometimes we get dates that the timezone package cannot handle very
 355     ;; gracefully - take care of this here, instead of in url-cookie-expired-p
 356     ;; to speed things up.
 357     (if (and expires
 358              (string-match
 359               (concat "^[^,]+, +\\(..\\)-\\(...\\)-\\(..\\) +"
 360                       "\\(..:..:..\\) +\\[*\\([^\]]+\\)\\]*$")
 361               expires))
 362         (setq expires (concat (match-string 1 expires) " "
 363                               (match-string 2 expires) " "
 364                               (match-string 3 expires) " "
 365                               (match-string 4 expires) " ["
 366                               (match-string 5 expires) "]")))
 367
 368     ;; This one is for older Emacs/XEmacs variants that don't
 369     ;; understand this format without tenths of a second in it.
 370     ;; Wednesday, 30-Dec-2037 16:00:00 GMT
 371     ;;       - vs -
 372     ;; Wednesday, 30-Dec-2037 16:00:00.00 GMT
 373     (if (and expires
 374              (string-match
 375               "\\([0-9]+\\)-\\([A-Za-z]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)\\(\\.[0-9]+\\)*[ \t]+\\([-+a-zA-Z0-9]+\\)"
 376               expires))
 377         (setq expires (concat (match-string 1 expires) "-"      ; day
 378                               (match-string 2 expires) "-"      ; month
 379                               (match-string 3 expires) " "      ; year
 380                               (match-string 4 expires) ".00 " ; hour:minutes:seconds
 381                               (match-string 6 expires)))) ":" ; timezone
 382
 383     (while (consp trusted)
 384       (if (string-match (car trusted) current-url)
 385           (setq trusted (- (match-end 0) (match-beginning 0)))
 386         (pop trusted)))
 387     (while (consp untrusted)
 388       (if (string-match (car untrusted) current-url)
 389           (setq untrusted (- (match-end 0) (match-beginning 0)))
 390         (pop untrusted)))
 391     (if (and trusted untrusted)
 392         ;; Choose the more specific match
 393         (if (> trusted untrusted)
 394             (setq untrusted nil)
 395           (setq trusted nil)))
 396     (cond
 397      (untrusted
 398       ;; The site was explicity marked as untrusted by the user
 399       nil)
 400      ((or (eq url-privacy-level 'paranoid)
 401           (and (listp url-privacy-level) (memq 'cookies url-privacy-level)))
 402       ;; user never wants cookies
 403       nil)
 404      ((and url-cookie-confirmation
 405            (not trusted)
 406            (save-window-excursion
 407              (with-output-to-temp-buffer "*Cookie Warning*"
 408                (mapcar
 409                 (function
 410                  (lambda (x)
 411                    (princ (format "%s - %s" (car x) (cdr x))))) rest))
 412              (prog1
 413                  (not (funcall url-confirmation-func
 414                                (format "Allow %s to set these cookies? "
 415                                        (url-host url-current-object))))
 416                (if (get-buffer "*Cookie Warning*")
 417                    (kill-buffer "*Cookie Warning*")))))
 418       ;; user wants to be asked, and declined.
 419       nil)
 420      ((url-cookie-host-can-set-p (url-host url-current-object) domain)
 421       ;; Cookie is accepted by the user, and passes our security checks
 422       (let ((cur nil))
 423         (while rest
 424           (setq cur (pop rest))
 425           (url-cookie-store (car cur) (cdr cur)
 426                             expires domain localpart secure))))
 427      (t
 428       (message "%s tried to set a cookie for domain %s - rejected."
 429                (url-host url-current-object) domain)))))
 430
 431 (defvar url-cookie-timer nil)
 432
 433 (defcustom url-cookie-save-interval 3600
 434   "The number of seconds between automatic saves of cookies.
 435 Default is 1 hour.  Note that if you change this variable outside of
 436 the `customize' interface after `url-do-setup' has been run, you need
 437 to run the `url-cookie-setup-save-timer' function manually."
 438   :set #'(lambda (var val)
 439            (set-default var val)
 440            (if (bound-and-true-p url-setup-done)
 441                (url-cookie-setup-save-timer)))
 442   :type 'integer
 443   :group 'url-cookie)
 444
 445 (defun url-cookie-setup-save-timer ()
 446   "Reset the cookie saver timer."
 447   (interactive)
 448   (ignore-errors (cancel-timer url-cookie-timer))
 449   (setq url-cookie-timer nil)
 450   (if url-cookie-save-interval
 451       (setq url-cookie-timer (run-at-time url-cookie-save-interval
 452                                           url-cookie-save-interval
 453                                           #'url-cookie-write-file))))
 454
 455 (provide 'url-cookie)
 456
 457 ;; arch-tag: 2568751b-6452-4398-aa2d-303edadb54d7
 458 ;;; url-cookie.el ends here