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 (defun url-cookie-clean-up (&optional secure)
  91   (let* (
  92          (var (if secure 'url-cookie-secure-storage 'url-cookie-storage))
  93          (val (symbol-value var))
  94          (cur nil)
  95          (new nil)
  96          (cookies nil)
  97          (cur-cookie nil)
  98          (new-cookies nil)
  99          )
 100     (while val
 101       (setq cur (car val)
 102             val (cdr val)
 103             new-cookies nil
 104             cookies (cdr cur))
 105       (while cookies
 106         (setq cur-cookie (car cookies)
 107               cookies (cdr cookies))
 108         (if (or (not (url-cookie-p cur-cookie))
 109                 (url-cookie-expired-p cur-cookie)
 110                 (null (url-cookie-expires cur-cookie)))
 111             nil
 112           (setq new-cookies (cons cur-cookie new-cookies))))
 113       (if (not new-cookies)
 114           nil
 115         (setcdr cur new-cookies)
 116         (setq new (cons cur new))))
 117     (set var new)))
 118
 119 (defun url-cookie-write-file (&optional fname)
 120   (setq fname (or fname url-cookie-file))
 121   (unless (file-directory-p (file-name-directory fname))
 122     (ignore-errors (make-directory (file-name-directory fname))))
 123   (cond
 124    ((not url-cookies-changed-since-last-save) nil)
 125    ((not (file-writable-p fname))
 126     (message "Cookies file %s (see variable `url-cookie-file') is unwritable." fname))
 127    (t
 128     (url-cookie-clean-up)
 129     (url-cookie-clean-up t)
 130     (with-current-buffer (get-buffer-create " *cookies*")
 131       (erase-buffer)
 132       (fundamental-mode)
 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       (kill-buffer (current-buffer))))))
 148
 149 (defun url-cookie-store (name value &optional expires domain localpart secure)
 150   "Store a netscape-style cookie."
 151   (let* ((storage (if secure url-cookie-secure-storage url-cookie-storage))
 152          (tmp storage)
 153          (cur nil)
 154          (found-domain nil))
 155
 156     ;; First, look for a matching domain
 157     (setq found-domain (assoc domain storage))
 158
 159     (if found-domain
 160         ;; Need to either stick the new cookie in existing domain storage
 161         ;; or possibly replace an existing cookie if the names match.
 162         (progn
 163           (setq storage (cdr found-domain)
 164                 tmp nil)
 165           (while storage
 166             (setq cur (car storage)
 167                   storage (cdr storage))
 168             (if (and (equal localpart (url-cookie-localpart cur))
 169                      (equal name (url-cookie-name cur)))
 170                 (progn
 171                   (setf (url-cookie-expires cur) expires)
 172                   (setf (url-cookie-value cur) value)
 173                   (setq tmp t))))
 174           (if (not tmp)
 175               ;; New cookie
 176               (setcdr found-domain (cons
 177                                     (url-cookie-create :name name
 178                                                        :value value
 179                                                        :expires expires
 180                                                        :domain domain
 181                                                        :localpart localpart
 182                                                        :secure secure)
 183                                     (cdr found-domain)))))
 184       ;; Need to add a new top-level domain
 185       (setq tmp (url-cookie-create :name name
 186                                    :value value
 187                                    :expires expires
 188                                    :domain domain
 189                                    :localpart localpart
 190                                    :secure secure))
 191       (cond
 192        (storage
 193         (setcdr storage (cons (list domain tmp) (cdr storage))))
 194        (secure
 195         (setq url-cookie-secure-storage (list (list domain tmp))))
 196        (t
 197         (setq url-cookie-storage (list (list domain tmp))))))))
 198
 199 (defun url-cookie-expired-p (cookie)
 200   (let* (
 201          (exp (url-cookie-expires cookie))
 202          (cur-date (and exp (timezone-parse-date (current-time-string))))
 203          (exp-date (and exp (timezone-parse-date exp)))
 204          (cur-greg (and cur-date (timezone-absolute-from-gregorian
 205                                   (string-to-number (aref cur-date 1))
 206                                   (string-to-number (aref cur-date 2))
 207                                   (string-to-number (aref cur-date 0)))))
 208          (exp-greg (and exp (timezone-absolute-from-gregorian
 209                              (string-to-number (aref exp-date 1))
 210                              (string-to-number (aref exp-date 2))
 211                              (string-to-number (aref exp-date 0)))))
 212          (diff-in-days (and exp (- cur-greg exp-greg)))
 213          )
 214     (cond
 215      ((not exp) nil)                    ; No expiry == expires at browser quit
 216      ((< diff-in-days 0) nil)           ; Expires sometime after today
 217      ((> diff-in-days 0) t)             ; Expired before today
 218      (t                                 ; Expires sometime today, check times
 219       (let* ((cur-time (timezone-parse-time (aref cur-date 3)))
 220              (exp-time (timezone-parse-time (aref exp-date 3)))
 221              (cur-norm (+ (* 360 (string-to-number (aref cur-time 2)))
 222                           (*  60 (string-to-number (aref cur-time 1)))
 223                           (*   1 (string-to-number (aref cur-time 0)))))
 224              (exp-norm (+ (* 360 (string-to-number (aref exp-time 2)))
 225                           (*  60 (string-to-number (aref exp-time 1)))
 226                           (*   1 (string-to-number (aref exp-time 0))))))
 227         (> (- cur-norm exp-norm) 1))))))
 228
 229 (defun url-cookie-retrieve (host localpart &optional secure)
 230   "Retrieve all the netscape-style cookies for a specified HOST and LOCALPART."
 231   (let ((storage (if secure
 232                      (append url-cookie-secure-storage url-cookie-storage)
 233                    url-cookie-storage))
 234         (case-fold-search t)
 235         (cookies nil)
 236         (cur nil)
 237         (retval nil)
 238         (localpart-regexp nil))
 239     (while storage
 240       (setq cur (car storage)
 241             storage (cdr storage)
 242             cookies (cdr cur))
 243       (if (and (car cur)
 244                (string-match
 245                 (concat "^.*"
 246                         (regexp-quote
 247                          ;; Remove the dot from wildcard domains
 248                          ;; before matching.
 249                          (if (eq ?. (aref (car cur) 0))
 250                              (substring (car cur) 1)
 251                            (car cur)))
 252                         "$") host))
 253           ;; The domains match - a possible hit!
 254           (while cookies
 255             (setq cur (car cookies)
 256                   cookies (cdr cookies)
 257                   localpart-regexp (concat "^" (regexp-quote
 258                                                 (url-cookie-localpart cur))))
 259             (if (and (string-match localpart-regexp localpart)
 260                      (not (url-cookie-expired-p cur)))
 261                 (setq retval (cons cur retval))))))
 262     retval))
 263
 264 (defun url-cookie-generate-header-lines (host localpart secure)
 265   (let* ((cookies (url-cookie-retrieve host localpart secure))
 266          (retval nil)
 267          (cur nil)
 268          (chunk nil))
 269     ;; Have to sort this for sending most specific cookies first
 270     (setq cookies (and cookies
 271                        (sort cookies
 272                              (function
 273                               (lambda (x y)
 274                                 (> (length (url-cookie-localpart x))
 275                                    (length (url-cookie-localpart y))))))))
 276     (while cookies
 277       (setq cur (car cookies)
 278             cookies (cdr cookies)
 279             chunk (format "%s=%s" (url-cookie-name cur) (url-cookie-value cur))
 280             retval (if (and url-cookie-multiple-line
 281                             (< 80 (+ (length retval) (length chunk) 4)))
 282                        (concat retval "\r\nCookie: " chunk)
 283                      (if retval
 284                          (concat retval "; " chunk)
 285                        (concat "Cookie: " chunk)))))
 286     (if retval
 287         (concat retval "\r\n")
 288       "")))
 289
 290 (defvar url-cookie-two-dot-domains
 291   (concat "\\.\\("
 292    (mapconcat 'identity (list "com" "edu" "net" "org" "gov" "mil" "int")
 293               "\\|")
 294    "\\)$")
 295   "A regexp of top level domains that only require two matching
 296 '.'s in the domain name in order to set a cookie.")
 297
 298 (defcustom url-cookie-trusted-urls nil
 299   "A list of regular expressions matching URLs to always accept cookies from."
 300   :type '(repeat regexp)
 301   :group 'url-cookie)
 302
 303 (defcustom url-cookie-untrusted-urls nil
 304   "A list of regular expressions matching URLs to never accept cookies from."
 305   :type '(repeat regexp)
 306   :group 'url-cookie)
 307
 308 (defun url-cookie-host-can-set-p (host domain)
 309   (let ((numdots 0)
 310         (last nil)
 311         (case-fold-search t)
 312         (mindots 3))
 313     (while (setq last (string-match "\\." domain last))
 314       (setq numdots (1+ numdots)
 315             last (1+ last)))
 316     (if (string-match url-cookie-two-dot-domains domain)
 317         (setq mindots 2))
 318     (cond
 319      ((string= host domain)             ; Apparently netscape lets you do this
 320       t)
 321      ((>= numdots mindots)              ; We have enough dots in domain name
 322       ;; Need to check and make sure the host is actually _in_ the
 323       ;; domain it wants to set a cookie for though.
 324       (string-match (concat (regexp-quote
 325                              ;; Remove the dot from wildcard domains
 326                              ;; before matching.
 327                              (if (eq ?. (aref domain 0))
 328                                  (substring domain 1)
 329                                domain))
 330                             "$") host))
 331      (t
 332       nil))))
 333
 334 (defun url-cookie-handle-set-cookie (str)
 335   (setq url-cookies-changed-since-last-save t)
 336   (let* ((args (url-parse-args str t))
 337          (case-fold-search t)
 338          (secure (and (assoc-string "secure" args t) t))
 339          (domain (or (cdr-safe (assoc-string "domain" args t))
 340                      (url-host url-current-object)))
 341          (current-url (url-view-url t))
 342          (trusted url-cookie-trusted-urls)
 343          (untrusted url-cookie-untrusted-urls)
 344          (expires (cdr-safe (assoc-string "expires" args t)))
 345          (localpart (or (cdr-safe (assoc-string "path" args t))
 346                         (file-name-directory
 347                          (url-filename url-current-object))))
 348          (rest nil))
 349     (while args
 350       (if (not (member (downcase (car (car args)))
 351                        '("secure" "domain" "expires" "path")))
 352           (setq rest (cons (car args) rest)))
 353       (setq args (cdr args)))
 354
 355     ;; Sometimes we get dates that the timezone package cannot handle very
 356     ;; gracefully - take care of this here, instead of in url-cookie-expired-p
 357     ;; to speed things up.
 358     (if (and expires
 359              (string-match
 360               (concat "^[^,]+, +\\(..\\)-\\(...\\)-\\(..\\) +"
 361                       "\\(..:..:..\\) +\\[*\\([^\]]+\\)\\]*$")
 362               expires))
 363         (setq expires (concat (match-string 1 expires) " "
 364                               (match-string 2 expires) " "
 365                               (match-string 3 expires) " "
 366                               (match-string 4 expires) " ["
 367                               (match-string 5 expires) "]")))
 368
 369     ;; This one is for older Emacs/XEmacs variants that don't
 370     ;; understand this format without tenths of a second in it.
 371     ;; Wednesday, 30-Dec-2037 16:00:00 GMT
 372     ;;       - vs -
 373     ;; Wednesday, 30-Dec-2037 16:00:00.00 GMT
 374     (if (and expires
 375              (string-match
 376               "\\([0-9]+\\)-\\([A-Za-z]+\\)-\\([0-9]+\\)[ \t]+\\([0-9]+:[0-9]+:[0-9]+\\)\\(\\.[0-9]+\\)*[ \t]+\\([-+a-zA-Z0-9]+\\)"
 377               expires))
 378         (setq expires (concat (match-string 1 expires) "-"      ; day
 379                               (match-string 2 expires) "-"      ; month
 380                               (match-string 3 expires) " "      ; year
 381                               (match-string 4 expires) ".00 " ; hour:minutes:seconds
 382                               (match-string 6 expires)))) ":" ; timezone
 383
 384     (while (consp trusted)
 385       (if (string-match (car trusted) current-url)
 386           (setq trusted (- (match-end 0) (match-beginning 0)))
 387         (pop trusted)))
 388     (while (consp untrusted)
 389       (if (string-match (car untrusted) current-url)
 390           (setq untrusted (- (match-end 0) (match-beginning 0)))
 391         (pop untrusted)))
 392     (if (and trusted untrusted)
 393         ;; Choose the more specific match
 394         (if (> trusted untrusted)
 395             (setq untrusted nil)
 396           (setq trusted nil)))
 397     (cond
 398      (untrusted
 399       ;; The site was explicity marked as untrusted by the user
 400       nil)
 401      ((or (eq url-privacy-level 'paranoid)
 402           (and (listp url-privacy-level) (memq 'cookies url-privacy-level)))
 403       ;; user never wants cookies
 404       nil)
 405      ((and url-cookie-confirmation
 406            (not trusted)
 407            (save-window-excursion
 408              (with-output-to-temp-buffer "*Cookie Warning*"
 409                (mapcar
 410                 (function
 411                  (lambda (x)
 412                    (princ (format "%s - %s" (car x) (cdr x))))) rest))
 413              (prog1
 414                  (not (funcall url-confirmation-func
 415                                (format "Allow %s to set these cookies? "
 416                                        (url-host url-current-object))))
 417                (if (get-buffer "*Cookie Warning*")
 418                    (kill-buffer "*Cookie Warning*")))))
 419       ;; user wants to be asked, and declined.
 420       nil)
 421      ((url-cookie-host-can-set-p (url-host url-current-object) domain)
 422       ;; Cookie is accepted by the user, and passes our security checks
 423       (let ((cur nil))
 424         (while rest
 425           (setq cur (pop rest))
 426           (url-cookie-store (car cur) (cdr cur)
 427                             expires domain localpart secure))))
 428      (t
 429       (message "%s tried to set a cookie for domain %s - rejected."
 430                (url-host url-current-object) domain)))))
 431
 432 (defvar url-cookie-timer nil)
 433
 434 (defcustom url-cookie-save-interval 3600
 435   "The number of seconds between automatic saves of cookies.
 436 Default is 1 hour.  Note that if you change this variable outside of
 437 the `customize' interface after `url-do-setup' has been run, you need
 438 to run the `url-cookie-setup-save-timer' function manually."
 439   :set #'(lambda (var val)
 440            (set-default var val)
 441            (if (bound-and-true-p url-setup-done)
 442                (url-cookie-setup-save-timer)))
 443   :type 'integer
 444   :group 'url-cookie)
 445
 446 (defun url-cookie-setup-save-timer ()
 447   "Reset the cookie saver timer."
 448   (interactive)
 449   (ignore-errors (cancel-timer url-cookie-timer))
 450   (setq url-cookie-timer nil)
 451   (if url-cookie-save-interval
 452       (setq url-cookie-timer (run-at-time url-cookie-save-interval
 453                                           url-cookie-save-interval
 454                                           #'url-cookie-write-file))))
 455
 456 (provide 'url-cookie)
 457
 458 ;; arch-tag: 2568751b-6452-4398-aa2d-303edadb54d7
 459 ;;; url-cookie.el ends here