1;;; gnus-nocem.el --- NoCeM pseudo-cancellation treatment 2 3;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 4;; 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org> 7;; Keywords: news 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., 51 Franklin Street, Fifth Floor, 24;; Boston, MA 02110-1301, USA. 25 26;;; Commentary: 27 28;;; Code: 29 30(eval-when-compile (require 'cl)) 31 32(require 'gnus) 33(require 'nnmail) 34(require 'gnus-art) 35(require 'gnus-sum) 36(require 'gnus-range) 37 38(defgroup gnus-nocem nil 39 "NoCeM pseudo-cancellation treatment." 40 :group 'gnus-score) 41 42(defcustom gnus-nocem-groups 43 '("news.lists.filters" "news.admin.net-abuse.bulletins" 44 "alt.nocem.misc" "news.admin.net-abuse.announce") 45 "*List of groups that will be searched for NoCeM messages." 46 :group 'gnus-nocem 47 :type '(repeat (string :tag "Group"))) 48 49(defcustom gnus-nocem-issuers 50 '("AutoMoose-1" ; CancelMoose[tm] 51 "clewis@ferret.ocunix" ; Chris Lewis 52 "cosmo.roadkill" 53 "SpamHippo" 54 "hweede@snafu.de") 55 "*List of NoCeM issuers to pay attention to. 56 57This can also be a list of `(ISSUER CONDITION ...)' elements. 58 59See <URL:http://www.xs4all.nl/~rosalind/nocemreg/nocemreg.html> for an 60issuer registry." 61 :group 'gnus-nocem 62 :link '(url-link "http://www.xs4all.nl/~rosalind/nocemreg/nocemreg.html") 63 :type '(repeat (choice string sexp))) 64 65(defcustom gnus-nocem-directory 66 (nnheader-concat gnus-article-save-directory "NoCeM/") 67 "*Directory where NoCeM files will be stored." 68 :group 'gnus-nocem 69 :type 'directory) 70 71(defcustom gnus-nocem-expiry-wait 15 72 "*Number of days to keep NoCeM headers in the cache." 73 :group 'gnus-nocem 74 :type 'integer) 75 76(defcustom gnus-nocem-verifyer 'pgg-verify 77 "*Function called to verify that the NoCeM message is valid. 78One likely value is `pgg-verify'. If the function in this variable 79isn't bound, the message will be used unconditionally." 80 :group 'gnus-nocem 81 :type '(radio (function-item pgg-verify) 82 (function-item mc-verify) 83 (function :tag "other"))) 84 85(defcustom gnus-nocem-liberal-fetch nil 86 "*If t try to fetch all messages which have @@NCM in the subject. 87Otherwise don't fetch messages which have references or whose message-id 88matches a previously scanned and verified nocem message." 89 :group 'gnus-nocem 90 :type 'boolean) 91 92(defcustom gnus-nocem-check-article-limit 500 93 "*If non-nil, the maximum number of articles to check in any NoCeM group." 94 :group 'gnus-nocem 95 :version "21.1" 96 :type '(choice (const :tag "unlimited" nil) 97 (integer 1000))) 98 99(defcustom gnus-nocem-check-from t 100 "Non-nil means check for valid issuers in message bodies. 101Otherwise don't bother fetching articles unless their author matches a 102valid issuer, which is much faster if you are selective about the issuers." 103 :group 'gnus-nocem 104 :version "21.1" 105 :type 'boolean) 106 107;;; Internal variables 108 109(defvar gnus-nocem-active nil) 110(defvar gnus-nocem-alist nil) 111(defvar gnus-nocem-touched-alist nil) 112(defvar gnus-nocem-hashtb nil) 113(defvar gnus-nocem-seen-message-ids nil) 114 115;;; Functions 116 117(defun gnus-nocem-active-file () 118 (concat (file-name-as-directory gnus-nocem-directory) "active")) 119 120(defun gnus-nocem-cache-file () 121 (concat (file-name-as-directory gnus-nocem-directory) "cache")) 122 123;; 124;; faster lookups for group names: 125;; 126 127(defvar gnus-nocem-real-group-hashtb nil 128 "Real-name mappings of subscribed groups.") 129 130(defun gnus-fill-real-hashtb () 131 "Fill up a hash table with the real-name mappings from the user's active file." 132 (setq gnus-nocem-real-group-hashtb (gnus-make-hashtable 133 (length gnus-newsrc-alist))) 134 (mapcar (lambda (group) 135 (setq group (gnus-group-real-name (car group))) 136 (gnus-sethash group t gnus-nocem-real-group-hashtb)) 137 gnus-newsrc-alist)) 138 139;;;###autoload 140(defun gnus-nocem-scan-groups () 141 "Scan all NoCeM groups for new NoCeM messages." 142 (interactive) 143 (let ((groups gnus-nocem-groups) 144 (gnus-inhibit-demon t) 145 group active gactive articles check-headers) 146 (gnus-make-directory gnus-nocem-directory) 147 ;; Load any previous NoCeM headers. 148 (gnus-nocem-load-cache) 149 ;; Get the group name mappings: 150 (gnus-fill-real-hashtb) 151 ;; Read the active file if it hasn't been read yet. 152 (and (file-exists-p (gnus-nocem-active-file)) 153 (not gnus-nocem-active) 154 (ignore-errors 155 (load (gnus-nocem-active-file) t t t))) 156 ;; Go through all groups and see whether new articles have 157 ;; arrived. 158 (while (setq group (pop groups)) 159 (if (not (setq gactive (gnus-activate-group group))) 160 () ; This group doesn't exist. 161 (setq active (nth 1 (assoc group gnus-nocem-active))) 162 (when (and (not (< (cdr gactive) (car gactive))) ; Empty group. 163 (or (not active) 164 (< (cdr active) (cdr gactive)))) 165 ;; Ok, there are new articles in this group, se we fetch the 166 ;; headers. 167 (save-excursion 168 (let ((dependencies (make-vector 10 nil)) 169 headers header) 170 (with-temp-buffer 171 (setq headers 172 (if (eq 'nov 173 (gnus-retrieve-headers 174 (setq articles 175 (gnus-uncompress-range 176 (cons 177 (if active (1+ (cdr active)) 178 (car gactive)) 179 (cdr gactive)))) 180 group)) 181 (gnus-get-newsgroup-headers-xover 182 articles nil dependencies) 183 (gnus-get-newsgroup-headers dependencies))) 184 (while (setq header (pop headers)) 185 ;; We take a closer look on all articles that have 186 ;; "@@NCM" in the subject. Unless we already read 187 ;; this cross posted message. Nocem messages 188 ;; are not allowed to have references, so we can 189 ;; ignore scanning followups. 190 (and (string-match "@@NCM" (mail-header-subject header)) 191 (and gnus-nocem-check-from 192 (let ((case-fold-search t)) 193 (catch 'ok 194 (mapcar 195 (lambda (author) 196 (if (consp author) 197 (setq author (car author))) 198 (if (string-match 199 author (mail-header-from header)) 200 (throw 'ok t))) 201 gnus-nocem-issuers) 202 nil))) 203 (or gnus-nocem-liberal-fetch 204 (and (or (string= "" (mail-header-references 205 header)) 206 (null (mail-header-references header))) 207 (not (member (mail-header-message-id header) 208 gnus-nocem-seen-message-ids)))) 209 (push header check-headers))) 210 (setq check-headers (last (nreverse check-headers) 211 gnus-nocem-check-article-limit)) 212 (let ((i 0) 213 (len (length check-headers))) 214 (dolist (h check-headers) 215 (gnus-message 216 7 "Checking article %d in %s for NoCeM (%d of %d)..." 217 (mail-header-number h) group (incf i) len) 218 (gnus-nocem-check-article group h))))))) 219 (setq gnus-nocem-active 220 (cons (list group gactive) 221 (delq (assoc group gnus-nocem-active) 222 gnus-nocem-active))))) 223 ;; Save the results, if any. 224 (gnus-nocem-save-cache) 225 (gnus-nocem-save-active))) 226 227(defun gnus-nocem-check-article (group header) 228 "Check whether the current article is an NCM article and that we want it." 229 ;; Get the article. 230 (let ((date (mail-header-date header)) 231 (gnus-newsgroup-name group) 232 issuer b e type) 233 (when (or (not date) 234 (time-less-p 235 (time-since (date-to-time date)) 236 (days-to-time gnus-nocem-expiry-wait))) 237 (gnus-request-article-this-buffer (mail-header-number header) group) 238 (goto-char (point-min)) 239 (when (re-search-forward 240 "-----BEGIN PGP\\( SIGNED\\)? MESSAGE-----" 241 nil t) 242 (delete-region (point-min) (match-beginning 0))) 243 (when (re-search-forward 244 "-----END PGP \\(MESSAGE\\|SIGNATURE\\)-----\n?" 245 nil t) 246 (delete-region (match-end 0) (point-max))) 247 (goto-char (point-min)) 248 ;; The article has to have proper NoCeM headers. 249 (when (and (setq b (search-forward "\n@@BEGIN NCM HEADERS\n" nil t)) 250 (setq e (search-forward "\n@@BEGIN NCM BODY\n" nil t))) 251 ;; We get the name of the issuer. 252 (narrow-to-region b e) 253 (setq issuer (mail-fetch-field "issuer") 254 type (mail-fetch-field "type")) 255 (widen) 256 (if (not (gnus-nocem-message-wanted-p issuer type)) 257 (message "invalid NoCeM issuer: %s" issuer) 258 (and (gnus-nocem-verify-issuer issuer) ; She is who she says she is. 259 (gnus-nocem-enter-article) ; We gobble the message. 260 (push (mail-header-message-id header) ; But don't come back for 261 gnus-nocem-seen-message-ids))))))) ; second helpings. 262 263(defun gnus-nocem-message-wanted-p (issuer type) 264 (let ((issuers gnus-nocem-issuers) 265 wanted conditions condition) 266 (cond 267 ;; Do the quick check first. 268 ((member issuer issuers) 269 t) 270 ((setq conditions (cdr (assoc issuer issuers))) 271 ;; Check whether we want this type. 272 (while (setq condition (pop conditions)) 273 (cond 274 ((stringp condition) 275 (when (string-match condition type) 276 (setq wanted t))) 277 ((and (consp condition) 278 (eq (car condition) 'not) 279 (stringp (cadr condition))) 280 (when (string-match (cadr condition) type) 281 (setq wanted nil))) 282 (t 283 (error "Invalid NoCeM condition: %S" condition)))) 284 wanted)))) 285 286(defun gnus-nocem-verify-issuer (person) 287 "Verify using PGP that the canceler is who she says she is." 288 (if (functionp gnus-nocem-verifyer) 289 (ignore-errors 290 (funcall gnus-nocem-verifyer)) 291 ;; If we don't have Mailcrypt, then we use the message anyway. 292 t)) 293 294(defun gnus-nocem-enter-article () 295 "Enter the current article into the NoCeM cache." 296 (goto-char (point-min)) 297 (let ((b (search-forward "\n@@BEGIN NCM BODY\n" nil t)) 298 (e (search-forward "\n@@END NCM BODY\n" nil t)) 299 (buf (current-buffer)) 300 ncm id group) 301 (when (and b e) 302 (narrow-to-region b (1+ (match-beginning 0))) 303 (goto-char (point-min)) 304 (while (search-forward "\t" nil t) 305 (cond 306 ((not (ignore-errors 307 (setq group (let ((obarray gnus-nocem-real-group-hashtb)) 308 (read buf))))) 309 ;; An error. 310 ) 311 ((not (symbolp group)) 312 ;; Ignore invalid entries. 313 ) 314 ((not (boundp group)) 315 ;; Make sure all entries in the hashtb are bound. 316 (set group nil)) 317 (t 318 (when (gnus-gethash (gnus-group-real-name (symbol-name group)) 319 gnus-nocem-real-group-hashtb) 320 ;; Valid group. 321 (beginning-of-line) 322 (while (eq (char-after) ?\t) 323 (forward-line -1)) 324 (setq id (buffer-substring (point) (1- (search-forward "\t")))) 325 (unless (if gnus-nocem-hashtb 326 (gnus-gethash id gnus-nocem-hashtb) 327 (setq gnus-nocem-hashtb (gnus-make-hashtable)) 328 nil) 329 ;; only store if not already present 330 (gnus-sethash id t gnus-nocem-hashtb) 331 (push id ncm)) 332 (forward-line 1) 333 (while (eq (char-after) ?\t) 334 (forward-line 1)))))) 335 (when ncm 336 (setq gnus-nocem-touched-alist t) 337 (push (cons (let ((time (current-time))) (setcdr (cdr time) nil) time) 338 ncm) 339 gnus-nocem-alist)) 340 t))) 341 342;;;###autoload 343(defun gnus-nocem-load-cache () 344 "Load the NoCeM cache." 345 (interactive) 346 (unless gnus-nocem-alist 347 ;; The buffer doesn't exist, so we create it and load the NoCeM 348 ;; cache. 349 (when (file-exists-p (gnus-nocem-cache-file)) 350 (load (gnus-nocem-cache-file) t t t) 351 (gnus-nocem-alist-to-hashtb)))) 352 353(defun gnus-nocem-save-cache () 354 "Save the NoCeM cache." 355 (when (and gnus-nocem-alist 356 gnus-nocem-touched-alist) 357 (with-temp-file (gnus-nocem-cache-file) 358 (gnus-prin1 `(setq gnus-nocem-alist ',gnus-nocem-alist))) 359 (setq gnus-nocem-touched-alist nil))) 360 361(defun gnus-nocem-save-active () 362 "Save the NoCeM active file." 363 (with-temp-file (gnus-nocem-active-file) 364 (gnus-prin1 `(setq gnus-nocem-active ',gnus-nocem-active)))) 365 366(defun gnus-nocem-alist-to-hashtb () 367 "Create a hashtable from the Message-IDs we have." 368 (let* ((alist gnus-nocem-alist) 369 (pprev (cons nil alist)) 370 (prev pprev) 371 (expiry (days-to-time gnus-nocem-expiry-wait)) 372 entry) 373 (setq gnus-nocem-hashtb (gnus-make-hashtable (* (length alist) 51))) 374 (while (setq entry (car alist)) 375 (if (not (time-less-p (time-since (car entry)) expiry)) 376 ;; This entry has expired, so we remove it. 377 (setcdr prev (cdr alist)) 378 (setq prev alist) 379 ;; This is ok, so we enter it into the hashtable. 380 (setq entry (cdr entry)) 381 (while entry 382 (gnus-sethash (car entry) t gnus-nocem-hashtb) 383 (setq entry (cdr entry)))) 384 (setq alist (cdr alist))))) 385 386(gnus-add-shutdown 'gnus-nocem-close 'gnus) 387 388(defun gnus-nocem-close () 389 "Clear internal NoCeM variables." 390 (setq gnus-nocem-alist nil 391 gnus-nocem-hashtb nil 392 gnus-nocem-active nil 393 gnus-nocem-touched-alist nil 394 gnus-nocem-seen-message-ids nil 395 gnus-nocem-real-group-hashtb nil)) 396 397(defun gnus-nocem-unwanted-article-p (id) 398 "Say whether article ID in the current group is wanted." 399 (and gnus-nocem-hashtb 400 (gnus-gethash id gnus-nocem-hashtb))) 401 402(provide 'gnus-nocem) 403 404;;; arch-tag: 0e0c74ea-2f8e-4f3e-8fff-09f767c1adef 405;;; gnus-nocem.el ends here 406