;;; mml2015.el --- MIME Security with Pretty Good Privacy (PGP)
-;; Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
-;; 2008, 2009, 2010 Free Software Foundation, Inc.
+;; Copyright (C) 2000-2013 Free Software Foundation, Inc.
;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
;; Keywords: PGP MIME MML
(config &optional minimum-version))
(declare-function epg-configuration "ext:epg-config" ())
+;; Maybe this should be in eg mml-sec.el (and have a different name).
+;; Then mml1991 would not need to require mml2015, and mml1991-use
+;; could be removed.
(defvar mml2015-use (or
(condition-case nil
(progn
'epg)
(error))
(progn
- (ignore-errors (require 'pgg))
- (and (fboundp 'pgg-sign-region)
- 'pgg))
+ (let ((abs-file (locate-library "pgg")))
+ ;; Don't load PGG if it is marked as obsolete
+ ;; (Emacs 24).
+ (when (and abs-file
+ (not (string-match "/obsolete/[^/]*\\'"
+ abs-file)))
+ (ignore-errors (require 'pgg))
+ (and (fboundp 'pgg-sign-region)
+ 'pgg))))
(progn (ignore-errors
(load "mc-toplev"))
(and (fboundp 'mc-encrypt-generic)
:type 'integer)
(defcustom mml2015-signers nil
- "A list of your own key ID which will be used to sign a message."
+ "A list of your own key ID(s) which will be used to sign a message.
+If set, it overrides the setting of `mml2015-sign-with-sender'."
:group 'mime-security
:type '(repeat (string :tag "Key ID")))
+(defcustom mml2015-sign-with-sender nil
+ "If t, use message sender so find a key to sign with."
+ :group 'mime-security
+ :type 'boolean
+ :version "24.1")
+
(defcustom mml2015-encrypt-to-self nil
"If t, add your own key ID to recipient list when encryption."
:group 'mime-security
:group 'mime-security
:type 'boolean)
+(defcustom mml2015-maximum-key-image-dimension 64
+ "The maximum dimension (width or height) of any key images."
+ :version "24.4"
+ :group 'mime-security
+ :type 'integer)
+
;; 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, and PGG) discard the output from GnuPG.
(defvar epg-user-id-alist)
(defvar epg-digest-algorithm-alist)
+(defvar epg-gpg-program)
(defvar inhibit-redisplay)
(autoload 'epg-make-context "epg")
(autoload 'epg-context-set-signers "epg")
(autoload 'epg-context-result-for "epg")
(autoload 'epg-new-signature-digest-algorithm "epg")
-(autoload 'epg-verify-result-to-string "epg")
(autoload 'epg-list-keys "epg")
(autoload 'epg-decrypt-string "epg")
(autoload 'epg-verify-string "epg")
(autoload 'epg-key-sub-key-list "epg")
(autoload 'epg-sub-key-capability "epg")
(autoload 'epg-sub-key-validity "epg")
+(autoload 'epg-sub-key-fingerprint "epg")
+(autoload 'epg-signature-key-id "epg")
+(autoload 'epg-signature-to-string "epg")
+(autoload 'epg-key-user-id-list "epg")
+(autoload 'epg-user-id-string "epg")
+(autoload 'epg-user-id-validity "epg")
(autoload 'epg-configuration "epg-config")
(autoload 'epg-expand-group "epg-config")
(autoload 'epa-select-keys "epa")
(cons password-cache-key-id mml2015-epg-secret-key-id-list))
(copy-sequence passphrase)))))
-(defun mml2015-epg-find-usable-key (keys usage)
- (catch 'found
+(defun mml2015-epg-check-user-id (key recipient)
+ (let ((pointer (epg-key-user-id-list key))
+ result)
+ (while pointer
+ (if (and (equal (car (mail-header-parse-address
+ (epg-user-id-string (car pointer))))
+ (car (mail-header-parse-address
+ recipient)))
+ (not (memq (epg-user-id-validity (car pointer))
+ '(revoked expired))))
+ (setq result t
+ pointer nil)
+ (setq pointer (cdr pointer))))
+ result))
+
+(defun mml2015-epg-check-sub-key (key usage)
+ (let ((pointer (epg-key-sub-key-list key))
+ result)
+ ;; The primary key will be marked as disabled, when the entire
+ ;; key is disabled (see 12 Field, Format of colon listings, in
+ ;; gnupg/doc/DETAILS)
+ (unless (memq 'disabled (epg-sub-key-capability (car pointer)))
+ (while pointer
+ (if (and (memq usage (epg-sub-key-capability (car pointer)))
+ (not (memq (epg-sub-key-validity (car pointer))
+ '(revoked expired))))
+ (setq result t
+ pointer nil)
+ (setq pointer (cdr pointer)))))
+ result))
+
+(defun mml2015-epg-find-usable-key (context name usage
+ &optional name-is-key-id)
+ (let ((keys (epg-list-keys context name))
+ key)
(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 'disabled (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)))))
+ (if (and (or name-is-key-id
+ ;; Non email user-id can be supplied through
+ ;; mml2015-signers if mml2015-encrypt-to-self is set.
+ ;; Treat it as valid, as it is user's intention.
+ (not (string-match "\\`<" name))
+ (mml2015-epg-check-user-id (car keys) name))
+ (mml2015-epg-check-sub-key (car keys) usage))
+ (setq key (car keys)
+ keys nil)
+ (setq keys (cdr keys))))
+ key))
+
+;; XXX: since gpg --list-secret-keys does not return validity of each
+;; key, `mml2015-epg-find-usable-key' defined above is not enough for
+;; secret keys. The function `mml2015-epg-find-usable-secret-key'
+;; below looks at appropriate public keys to check usability.
+(defun mml2015-epg-find-usable-secret-key (context name usage)
+ (let ((secret-keys (epg-list-keys context name t))
+ secret-key)
+ (while (and (not secret-key) secret-keys)
+ (if (mml2015-epg-find-usable-key
+ context
+ (epg-sub-key-fingerprint
+ (car (epg-key-sub-key-list
+ (car secret-keys))))
+ usage
+ t)
+ (setq secret-key (car secret-keys)
+ secret-keys nil)
+ (setq secret-keys (cdr secret-keys))))
+ secret-key))
+
+(defun mml2015-epg-key-image (key-id)
+ "Return the image of a key, if any"
+ (with-temp-buffer
+ (mm-set-buffer-multibyte nil)
+ (let* ((coding-system-for-write 'binary)
+ (coding-system-for-read 'binary)
+ (data (shell-command-to-string
+ (format "%s --list-options no-show-photos --attribute-fd 3 --list-keys %s 3>&1 >/dev/null 2>&1"
+ (shell-quote-argument epg-gpg-program) key-id))))
+ (when (> (length data) 0)
+ (insert (substring data 16))
+ (condition-case nil
+ (gnus-create-image (buffer-string) nil t)
+ (error))))))
+
+(autoload 'gnus-rescale-image "gnus-util")
+
+(defun mml2015-epg-key-image-to-string (key-id)
+ "Return a string with the image of a key, if any"
+ (let* ((result "")
+ (key-image (mml2015-epg-key-image key-id)))
+ (when key-image
+ (setq result " ")
+ (put-text-property
+ 1 2 'display
+ (gnus-rescale-image key-image
+ (cons mml2015-maximum-key-image-dimension
+ mml2015-maximum-key-image-dimension))
+ result))
+ result))
+
+(defun mml2015-epg-signature-to-string (signature)
+ (concat (epg-signature-to-string signature)
+ (mml2015-epg-key-image-to-string (epg-signature-key-id signature))))
+
+(defun mml2015-epg-verify-result-to-string (verify-result)
+ (mapconcat #'mml2015-epg-signature-to-string verify-result "\n"))
(defun mml2015-epg-decrypt (handle ctl)
(catch 'error
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-info
(concat "OK\n"
- (epg-verify-result-to-string
+ (mml2015-epg-verify-result-to-string
(epg-context-result-for context 'verify))))
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-info "OK"))
(if (epg-context-result-for context 'verify)
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-details
- (epg-verify-result-to-string
+ (mml2015-epg-verify-result-to-string
(epg-context-result-for context 'verify)))))))
(defun mml2015-epg-verify (handle ctl)
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-info "Corrupted")
(throw 'error handle))
- (setq part (mm-replace-in-string part "\n" "\r\n" t)
+ (setq part (mm-replace-in-string part "\n" "\r\n")
signature (mm-get-part signature)
context (epg-make-context))
(condition-case error
(throw 'error handle)))
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-info
- (epg-verify-result-to-string (epg-context-result-for context 'verify)))
+ (mml2015-epg-verify-result-to-string
+ (epg-context-result-for context 'verify)))
handle)))
(defun mml2015-epg-clear-verify ()
(progn
(mm-set-handle-multipart-parameter
mm-security-handle 'gnus-info
- (epg-verify-result-to-string
+ (mml2015-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)))
(context (epg-make-context))
(boundary (mml-compute-boundary cont))
(sender (message-options-get 'message-sender))
+ (signer-names (or mml2015-signers
+ (if (and mml2015-sign-with-sender sender)
+ (list (concat "<" sender ">")))))
signer-key
(signers
(or (message-options-get 'mml2015-epg-signers)
(epa-select-keys context "\
Select keys for signing.
If no one is selected, default secret key is used. "
- (if sender
- (cons (concat "<" sender ">")
- mml2015-signers)
- mml2015-signers)
+ signer-names
t)
(if (or sender mml2015-signers)
(delq nil
(mapcar
(lambda (signer)
- (setq signer-key (mml2015-epg-find-usable-key
- (epg-list-keys context signer t)
- 'sign))
+ (setq signer-key
+ (mml2015-epg-find-usable-secret-key
+ context signer 'sign))
(unless (or signer-key
(y-or-n-p
(format
signer)))
(error "No secret key for %s" signer))
signer-key)
- (if sender
- (cons (concat "<" sender ">")
- mml2015-signers)
- mml2015-signers))))))))
+ signer-names)))))))
signature micalg)
(epg-context-set-armor context t)
(epg-context-set-textmode context t)
(epg-context-set-passphrase-callback
context
#'mml2015-epg-passphrase-callback))
+ ;; Signed data must end with a newline (RFC 3156, 5).
+ (goto-char (point-max))
+ (unless (bolp)
+ (insert "\n"))
(condition-case error
(setq signature (epg-sign-string context (buffer-string) t)
mml2015-epg-secret-key-id-list nil)
(insert (format "\n--%s\n" boundary))
(goto-char (point-max))
(insert (format "\n--%s\n" boundary))
- (insert "Content-Type: application/pgp-signature\n\n")
+ (insert "Content-Type: application/pgp-signature; name=\"signature.asc\"\n\n")
(insert signature)
(goto-char (point-max))
(insert (format "--%s--\n" boundary))
(goto-char (point-max))))
(defun mml2015-epg-encrypt (cont &optional sign)
- (let ((inhibit-redisplay t)
- (context (epg-make-context))
- (config (epg-configuration))
- (sender (message-options-get 'message-sender))
- (recipients (message-options-get 'mml2015-epg-recipients))
- cipher signers
- (boundary (mml-compute-boundary cont))
- recipient-key signer-key)
+ (let* ((inhibit-redisplay t)
+ (context (epg-make-context))
+ (boundary (mml-compute-boundary cont))
+ (config (epg-configuration))
+ (recipients (message-options-get 'mml2015-epg-recipients))
+ cipher
+ (sender (message-options-get 'message-sender))
+ (signer-names (or mml2015-signers
+ (if (and mml2015-sign-with-sender sender)
+ (list (concat "<" sender ">")))))
+ signers
+ recipient-key signer-key)
(unless recipients
(setq recipients
(apply #'nconc
(read-string "Recipients: ")))
"[ \f\t\n\r\v,]+"))))
(when mml2015-encrypt-to-self
- (unless (or sender mml2015-signers)
- (error "Message sender and mml2015-signers not set"))
- (setq recipients (nconc recipients (if sender
- (cons (concat "<" sender ">")
- mml2015-signers)
- mml2015-signers))))
+ (unless signer-names
+ (error "Neither message sender nor mml2015-signers are set"))
+ (setq recipients (nconc recipients signer-names)))
(if (eq mm-encrypt-option 'guided)
(setq recipients
(epa-select-keys context "\
(mapcar
(lambda (recipient)
(setq recipient-key (mml2015-epg-find-usable-key
- (epg-list-keys context recipient)
- 'encrypt))
+ context recipient 'encrypt))
(unless (or recipient-key
(y-or-n-p
(format "No public key for %s; skip it? "
(epa-select-keys context "\
Select keys for signing.
If no one is selected, default secret key is used. "
- (if sender
- (cons (concat "<" sender ">")
- mml2015-signers)
- mml2015-signers)
+ signer-names
t)
(if (or sender mml2015-signers)
(delq nil
(mapcar
(lambda (signer)
- (setq signer-key (mml2015-epg-find-usable-key
- (epg-list-keys context signer t)
- 'sign))
+ (setq signer-key
+ (mml2015-epg-find-usable-secret-key
+ context signer 'sign))
(unless (or signer-key
(y-or-n-p
(format
signer)))
(error "No secret key for %s" signer))
signer-key)
- (if sender
- (cons (concat "<" sender ">") mml2015-signers)
- mml2015-signers))))))))
+ signer-names)))))))
(epg-context-set-signers context signers))
(epg-context-set-armor context t)
(epg-context-set-textmode context t)
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