X-Git-Url: https://cgit.sxemacs.org/?a=blobdiff_plain;f=lisp%2Fmml2015.el;h=1b1ba0d855b3802875ab88ecdc0b3459e46ab942;hb=c358f44b1670d12d5eff5fe5a447a19afd34a252;hp=71c4ee624a24d073e398ef4b0de6ac76cdf0b535;hpb=22f7dc0931bb416a9520d4792f81a7a820e71db1;p=gnus

diff --git a/lisp/mml2015.el b/lisp/mml2015.el
index 71c4ee624..1b1ba0d85 100644
--- a/lisp/mml2015.el
+++ b/lisp/mml2015.el
@@ -1,7 +1,7 @@
 ;;; mml2015.el --- MIME Security with Pretty Good Privacy (PGP)
 
 ;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007 Free Software Foundation, Inc.
+;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
 
 ;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
 ;; Keywords: PGP MIME MML
@@ -10,7 +10,7 @@
 
 ;; GNU Emacs is free software; you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published
-;; by the Free Software Foundation; either version 2, or (at your
+;; by the Free Software Foundation; either version 3, or (at your
 ;; option) any later version.
 
 ;; GNU Emacs is distributed in the hope that it will be useful, but
@@ -30,6 +30,10 @@
 
 ;;; Code:
 
+;; For Emacs < 22.2.
+(eval-and-compile
+  (unless (fboundp 'declare-function) (defmacro declare-function (&rest r))))
+
 (eval-when-compile (require 'cl))
 (require 'mm-decode)
 (require 'mm-util)
@@ -38,6 +42,10 @@
 
 (defvar mc-pgp-always-sign)
 
+(declare-function epg-check-configuration "ext:epg-config"
+                  (config &optional minimum-version))
+(declare-function epg-configuration "ext:epg-config" ())
+
 (defvar mml2015-use (or
 		     (condition-case nil
 			 (progn
@@ -141,6 +149,28 @@ Whether the passphrase is cached at all is controlled by
   :group 'mime-security
   :type 'boolean)
 
+;; Extract plaintext from cleartext signature.  IMO, this kind of task
+;; should be done by GnuPG rather than Elisp, but older PGP backends
+;; (such as Mailcrypt, PGG, and gpg.el) discard the output from GnuPG.
+(defun mml2015-extract-cleartext-signature ()
+  (goto-char (point-min))
+  (forward-line)
+  ;; We need to be careful not to strip beyond the armor headers.
+  ;; Previously, an attacker could replace the text inside our
+  ;; markup with trailing garbage by injecting whitespace into the
+  ;; message.
+  (while (looking-at "Hash:")		; The only header allowed in cleartext
+    (forward-line))			; signatures according to RFC2440.
+  (when (looking-at "[\t ]*$")
+    (forward-line))
+  (delete-region (point-min) (point))
+  (if (re-search-forward "^-----BEGIN PGP SIGNATURE-----" nil t)
+      (delete-region (match-beginning 0) (point-max)))
+  (goto-char (point-min))
+  (while (re-search-forward "^- " nil t)
+    (replace-match "" t t)
+    (forward-line 1)))
+
 ;;; mailcrypt wrapper
 
 (eval-and-compile
@@ -151,9 +181,8 @@ Whether the passphrase is cached at all is controlled by
   (autoload 'mc-cleanup-recipient-headers "mc-toplev")
   (autoload 'mc-sign-generic "mc-toplev"))
 
-(eval-when-compile
-  (defvar mc-default-scheme)
-  (defvar mc-schemes))
+(defvar mc-default-scheme)
+(defvar mc-schemes)
 
 (defvar mml2015-decrypt-function 'mailcrypt-decrypt)
 (defvar mml2015-verify-function 'mailcrypt-verify)
@@ -327,7 +356,8 @@ Whether the passphrase is cached at all is controlled by
 	(mm-set-handle-multipart-parameter
 	 mm-security-handle 'gnus-info "OK")
       (mm-set-handle-multipart-parameter
-       mm-security-handle 'gnus-info "Failed"))))
+       mm-security-handle 'gnus-info "Failed")))
+  (mml2015-extract-cleartext-signature))
 
 (defun mml2015-mailcrypt-sign (cont)
   (mc-sign-generic (message-options-get 'message-sender)
@@ -374,6 +404,10 @@ Whether the passphrase is cached at all is controlled by
     (insert (format "--%s--\n" boundary))
     (goto-char (point-max))))
 
+;; We require mm-decode, which requires mm-bodies, which autoloads
+;; message-options-get (!).
+(declare-function message-options-set "message" (symbol value))
+
 (defun mml2015-mailcrypt-encrypt (cont &optional sign)
   (let ((mc-pgp-always-sign
 	 (or mc-pgp-always-sign
@@ -593,7 +627,8 @@ Whether the passphrase is cached at all is controlled by
        (with-current-buffer mml2015-result-buffer
 	 (mml2015-gpg-extract-signature-details)))
     (mm-set-handle-multipart-parameter
-     mm-security-handle 'gnus-info "Failed")))
+     mm-security-handle 'gnus-info "Failed"))
+  (mml2015-extract-cleartext-signature))
 
 (defun mml2015-gpg-sign (cont)
   (let ((boundary (mml-compute-boundary cont))
@@ -683,10 +718,9 @@ Whether the passphrase is cached at all is controlled by
 
 ;;; pgg wrapper
 
-(eval-when-compile
-  (defvar pgg-default-user-id)
-  (defvar pgg-errors-buffer)
-  (defvar pgg-output-buffer))
+(defvar pgg-default-user-id)
+(defvar pgg-errors-buffer)
+(defvar pgg-output-buffer)
 
 (eval-and-compile
   (autoload 'pgg-decrypt-region "pgg")
@@ -856,7 +890,8 @@ Whether the passphrase is cached at all is controlled by
 	 (with-current-buffer pgg-errors-buffer
 	   (mml2015-gpg-extract-signature-details)))
       (mm-set-handle-multipart-parameter
-       mm-security-handle 'gnus-info "Failed"))))
+       mm-security-handle 'gnus-info "Failed")))
+  (mml2015-extract-cleartext-signature))
 
 (defun mml2015-pgg-sign (cont)
   (let ((pgg-errors-buffer mml2015-result-buffer)
@@ -920,13 +955,12 @@ Whether the passphrase is cached at all is controlled by
 
 ;;; epg wrapper
 
-(eval-and-compile
-  (autoload 'epg-make-context "epg"))
+(defvar epg-user-id-alist)
+(defvar epg-digest-algorithm-alist)
+(defvar inhibit-redisplay)
 
-(eval-when-compile
-  (defvar epg-user-id-alist)
-  (defvar epg-digest-algorithm-alist)
-  (defvar inhibit-redisplay)
+(eval-and-compile
+  (autoload 'epg-make-context "epg")
   (autoload 'epg-context-set-armor "epg")
   (autoload 'epg-context-set-textmode "epg")
   (autoload 'epg-context-set-signers "epg")
@@ -940,15 +974,14 @@ Whether the passphrase is cached at all is controlled by
   (autoload 'epg-encrypt-string "epg")
   (autoload 'epg-passphrase-callback-function "epg")
   (autoload 'epg-context-set-passphrase-callback "epg")
+  (autoload 'epg-key-sub-key-list "epg")
+  (autoload 'epg-sub-key-capability "epg")
+  (autoload 'epg-sub-key-validity "epg")
   (autoload 'epg-configuration "epg-config")
   (autoload 'epg-expand-group "epg-config")
   (autoload 'epa-select-keys "epa"))
 
-(eval-when-compile
-  (defvar password-cache-expiry)
-  (autoload 'password-read "password")
-  (autoload 'password-cache-add "password")
-  (autoload 'password-cache-remove "password"))
+(defvar password-cache-expiry)
 
 (defvar mml2015-epg-secret-key-id-list nil)
 
@@ -973,6 +1006,18 @@ Whether the passphrase is cached at all is controlled by
 	      (cons key-id mml2015-epg-secret-key-id-list))
 	(copy-sequence passphrase)))))
 
+(defun mml2015-epg-find-usable-key (keys usage)
+  (catch 'found
+    (while keys
+      (let ((pointer (epg-key-sub-key-list (car keys))))
+	(while pointer
+	  (if (and (memq usage (epg-sub-key-capability (car pointer)))
+		   (not (memq (epg-sub-key-validity (car pointer))
+			      '(revoked expired))))
+	      (throw 'found (car keys)))
+	  (setq pointer (cdr pointer))))
+      (setq keys (cdr keys)))))
+
 (defun mml2015-epg-decrypt (handle ctl)
   (catch 'error
     (let ((inhibit-redisplay t)
@@ -1069,7 +1114,7 @@ Whether the passphrase is cached at all is controlled by
 (defun mml2015-epg-verify (handle ctl)
   (catch 'error
     (let ((inhibit-redisplay t)
-	  context plain signature-file part signature (index 0))
+	  context plain signature-file part signature)
       (when (or (null (setq part (mm-find-raw-part-by-type
 				  ctl (or (mm-handle-multipart-ctl-parameter
 					   ctl 'protocol)
@@ -1081,14 +1126,11 @@ Whether the passphrase is cached at all is controlled by
 	(mm-set-handle-multipart-parameter
 	 mm-security-handle 'gnus-info "Corrupted")
 	(throw 'error handle))
-      (while (string-match "\r?\n" part index)
-	(if (eq (aref part (match-beginning 0)) ?\r)
-	    (setq index (match-end 0))
-	  (setq part (replace-match "\r\n" t t part)
-		index (1+ (match-end 0)))))
-      (setq context (epg-make-context))
+      (setq part (mm-replace-in-string part "\n" "\r\n" t)
+	    signature (mm-get-part signature)
+	    context (epg-make-context))
       (condition-case error
-	  (setq plain (epg-verify-string context (mm-get-part signature) part))
+	  (setq plain (epg-verify-string context signature part))
 	(error
 	 (mm-set-handle-multipart-parameter
 	  mm-security-handle 'gnus-info "Failed")
@@ -1107,7 +1149,7 @@ Whether the passphrase is cached at all is controlled by
   (let ((inhibit-redisplay t)
 	(context (epg-make-context))
 	(signature (mm-encode-coding-string (buffer-string)
-					    buffer-file-coding-system))
+					    coding-system-for-write))
 	plain)
     (condition-case error
 	(setq plain (epg-verify-string context signature))
@@ -1120,40 +1162,43 @@ Whether the passphrase is cached at all is controlled by
 	 (mm-set-handle-multipart-parameter
 	  mm-security-handle 'gnus-details (mml2015-format-error error)))))
     (if plain
-	(mm-set-handle-multipart-parameter
-	 mm-security-handle 'gnus-info
-	 (epg-verify-result-to-string
-	  (epg-context-result-for context 'verify))))))
+	(progn
+	  (mm-set-handle-multipart-parameter
+	   mm-security-handle 'gnus-info
+	   (epg-verify-result-to-string
+	    (epg-context-result-for context 'verify)))
+	  (delete-region (point-min) (point-max))
+	  (insert (mm-decode-coding-string plain coding-system-for-read)))
+      (mml2015-extract-cleartext-signature))))
 
 (defun mml2015-epg-sign (cont)
   (let* ((inhibit-redisplay t)
-	(context (epg-make-context))
-	(boundary (mml-compute-boundary cont))
-	signer-keys
-	(signers
-	 (or (message-options-get 'mml2015-epg-signers)
-	     (message-options-set
-	      'mml2015-epg-signers
-	      (if mml2015-verbose
-		  (epa-select-keys context "\
+	 (context (epg-make-context))
+	 (boundary (mml-compute-boundary cont))
+	 signer-key
+	 (signers
+	  (or (message-options-get 'mml2015-epg-signers)
+	      (message-options-set
+	       'mml2015-epg-signers
+	       (if mml2015-verbose
+		   (epa-select-keys context "\
 Select keys for signing.
 If no one is selected, default secret key is used.  "
-				   mml2015-signers t)
-		(if mml2015-signers
-		    (apply #'nconc
-			   (mapcar
-			    (lambda (signer)
-			      (setq signer-keys
-				    (epg-list-keys context signer t))
-			      (unless (or signer-keys
-					  (y-or-n-p
-					   (format
-					    "No secret key for %s; skip it? "
-					    signer)))
-				(error "No secret key for %s" signer))
-			      signer-keys)
-			    mml2015-signers)))))))
-	signature micalg)
+				    mml2015-signers t)
+		 (if mml2015-signers
+		     (mapcar
+		      (lambda (signer)
+			(setq signer-key (mml2015-epg-find-usable-key
+					  (epg-list-keys context signer t)
+					  'sign))
+			(unless (or signer-key
+				    (y-or-n-p
+				     (format "No secret key for %s; skip it? "
+					     signer)))
+			  (error "No secret key for %s" signer))
+			signer-key)
+		      mml2015-signers))))))
+	 signature micalg)
     (epg-context-set-armor context t)
     (epg-context-set-textmode context t)
     (epg-context-set-signers context signers)
@@ -1198,7 +1243,7 @@ If no one is selected, default secret key is used.  "
 	(recipients (message-options-get 'mml2015-epg-recipients))
 	cipher signers
 	(boundary (mml-compute-boundary cont))
-	recipient-keys signer-keys)
+	recipient-key signer-key)
     (unless recipients
       (setq recipients
 	    (apply #'nconc
@@ -1222,17 +1267,18 @@ Select recipients for encryption.
 If no one is selected, symmetric encryption will be performed.  "
 				 recipients))
 	(setq recipients
-	      (apply #'nconc
-		     (mapcar
-		      (lambda (recipient)
-			(setq recipient-keys (epg-list-keys context recipient))
-			(unless (or recipient-keys
-				    (y-or-n-p
-				     (format "No public key for %s; skip it? "
-					     recipient)))
-			  (error "No public key for %s" recipient))
-			recipient-keys)
-		      recipients)))
+	      (mapcar
+	       (lambda (recipient)
+		 (setq recipient-key (mml2015-epg-find-usable-key
+				      (epg-list-keys context recipient)
+				      'encrypt))
+		 (unless (or recipient-key
+			     (y-or-n-p
+			      (format "No public key for %s; skip it? "
+				      recipient)))
+		   (error "No public key for %s" recipient))
+		 recipient-key)
+	       recipients))
 	(unless recipients
 	  (error "No recipient specified")))
       (message-options-set 'mml2015-epg-recipients recipients))
@@ -1247,19 +1293,19 @@ Select keys for signing.
 If no one is selected, default secret key is used.  "
 				      mml2015-signers t)
 		   (if mml2015-signers
-		       (apply #'nconc
-			      (mapcar
-			       (lambda (signer)
-				 (setq signer-keys
-				       (epg-list-keys context signer t))
-				 (unless (or signer-keys
-					     (y-or-n-p
-					      (format
-					       "No secret key for %s; skip it? "
-					       signer)))
-				   (error "No secret key for %s" signer))
-				 signer-keys)
-			       mml2015-signers)))))))
+		       (mapcar
+			(lambda (signer)
+			  (setq signer-key (mml2015-epg-find-usable-key
+					    (epg-list-keys context signer t)
+					    'sign))
+			  (unless (or signer-key
+				      (y-or-n-p
+				       (format
+					"No secret key for %s; skip it? "
+					signer)))
+			    (error "No secret key for %s" signer))
+			  signer-key)
+			mml2015-signers))))))
       (epg-context-set-signers context signers))
     (epg-context-set-armor context t)
     (epg-context-set-textmode context t)
@@ -1295,6 +1341,9 @@ If no one is selected, default secret key is used.  "
 
 ;;; General wrapper
 
+(autoload 'gnus-buffer-live-p "gnus-util")
+(autoload 'gnus-get-buffer-create "gnus")
+
 (defun mml2015-clean-buffer ()
   (if (gnus-buffer-live-p mml2015-result-buffer)
       (with-current-buffer mml2015-result-buffer