-;;; plstore.el --- searchable, partially encrypted, persistent plist store -*- lexical-binding: t -*-
-;; Copyright (C) 2011 Free Software Foundation, Inc.
+;;; plstore.el --- secure plist store -*- lexical-binding: t -*-
+;; Copyright (C) 2011-2012 Free Software Foundation, Inc.
;; Author: Daiki Ueno <ueno@unixuser.org>
;; Keywords: PGP, GnuPG
;;; Commentary
+;; Plist based data store providing search and partial encryption.
+;;
;; Creating:
;;
+;; ;; Open a new store associated with ~/.emacs.d/auth.plist.
;; (setq store (plstore-open (expand-file-name "~/.emacs.d/auth.plist")))
+;; ;; Both `:host' and `:port' are public property.
;; (plstore-put store "foo" '(:host "foo.example.org" :port 80) nil)
+;; ;; No encryption will be needed.
;; (plstore-save store)
-;; ;; :user property is secret
+;;
+;; ;; `:user' is marked as secret.
;; (plstore-put store "bar" '(:host "bar.example.org") '(:user "test"))
-;; (plstore-put store "baz" '(:host "baz.example.org") '(:user "test"))
-;; (plstore-save store) ;<= will ask passphrase via GPG
+;; ;; `:password' is marked as secret.
+;; (plstore-put store "baz" '(:host "baz.example.org") '(:password "test"))
+;; ;; Those secret properties are encrypted together.
+;; (plstore-save store)
+;;
+;; ;; Kill the buffer visiting ~/.emacs.d/auth.plist.
;; (plstore-close store)
;;
;; Searching:
;;
;; (setq store (plstore-open (expand-file-name "~/.emacs.d/auth.plist")))
+;;
+;; ;; As the entry "foo" associated with "foo.example.org" has no
+;; ;; secret properties, no need to decryption.
;; (plstore-find store '(:host ("foo.example.org")))
-;; (plstore-find store '(:host ("bar.example.org"))) ;<= will ask passphrase via GPG
+;;
+;; ;; As the entry "bar" associated with "bar.example.org" has a
+;; ;; secret property `:user', Emacs tries to decrypt the secret (and
+;; ;; thus you will need to input passphrase).
+;; (plstore-find store '(:host ("bar.example.org")))
+;;
+;; ;; While the entry "baz" associated with "baz.example.org" has also
+;; ;; a secret property `:password', it is encrypted together with
+;; ;; `:user' of "bar", so no need to decrypt the secret.
+;; (plstore-find store '(:host ("bar.example.org")))
+;;
;; (plstore-close store)
;;
+;; Editing:
+;;
+;; Currently not supported but in the future plstore will provide a
+;; major mode to edit PLSTORE files.
;;; Code:
(require 'epg)
+(defgroup plstore nil
+ "Searchable, partially encrypted, persistent plist store"
+ :version "24.1"
+ :group 'files)
+
+(defcustom plstore-select-keys 'silent
+ "Control whether or not to pop up the key selection dialog.
+
+If t, always asks user to select recipients.
+If nil, query user only when a file's default recipients are not
+known (i.e. `plstore-encrypt-to' is not locally set in the buffer
+visiting a plstore file).
+If neither t nor nil, doesn't ask user."
+ :type '(choice (const :tag "Ask always" t)
+ (const :tag "Ask when recipients are not set" nil)
+ (const :tag "Don't ask" silent))
+ :group 'plstore)
+
+(defvar plstore-encrypt-to nil
+ "*Recipient(s) used for encrypting secret entries.
+May either be a string or a list of strings. If it is nil,
+symmetric encryption will be used.")
+
+(put 'plstore-encrypt-to 'safe-local-variable
+ (lambda (val)
+ (or (stringp val)
+ (and (listp val)
+ (catch 'safe
+ (mapc (lambda (elt)
+ (unless (stringp elt)
+ (throw 'safe nil)))
+ val)
+ t)))))
+
+(put 'plstore-encrypt-to 'permanent-local t)
+
(defvar plstore-cache-passphrase-for-symmetric-encryption nil)
(defvar plstore-passphrase-alist nil)
(message "%s...%d%%" handback
(if (> total 0) (floor (* (/ current (float total)) 100)) 0))))
-(defun plstore--get-buffer (this)
- (aref this 0))
+(defun plstore--get-buffer (arg)
+ (aref arg 0))
-(defun plstore--get-alist (this)
- (aref this 1))
+(defun plstore--get-alist (arg)
+ (aref arg 1))
-(defun plstore--get-encrypted-data (this)
- (aref this 2))
+(defun plstore--get-encrypted-data (arg)
+ (aref arg 2))
-(defun plstore--get-secret-alist (this)
- (aref this 3))
+(defun plstore--get-secret-alist (arg)
+ (aref arg 3))
-(defun plstore--get-merged-alist (this)
- (aref this 4))
+(defun plstore--get-merged-alist (arg)
+ (aref arg 4))
-(defun plstore--set-file (this file)
- (aset this 0 file))
+(defun plstore--set-buffer (arg buffer)
+ (aset arg 0 buffer))
-(defun plstore--set-alist (this plist)
- (aset this 1 plist))
+(defun plstore--set-alist (arg plist)
+ (aset arg 1 plist))
-(defun plstore--set-encrypted-data (this encrypted-data)
- (aset this 2 encrypted-data))
+(defun plstore--set-encrypted-data (arg encrypted-data)
+ (aset arg 2 encrypted-data))
-(defun plstore--set-secret-alist (this secret-alist)
- (aset this 3 secret-alist))
+(defun plstore--set-secret-alist (arg secret-alist)
+ (aset arg 3 secret-alist))
-(defun plstore--set-merged-alist (this merged-alist)
- (aset this 4 merged-alist))
+(defun plstore--set-merged-alist (arg merged-alist)
+ (aset arg 4 merged-alist))
-(defun plstore-get-file (this)
- (buffer-file-name (plstore--get-buffer this)))
+(defun plstore-get-file (arg)
+ (buffer-file-name (plstore--get-buffer arg)))
+
+(defun plstore--make (&optional buffer alist encrypted-data secret-alist
+ merged-alist)
+ (vector buffer alist encrypted-data secret-alist merged-alist))
+
+(defun plstore--init-from-buffer (plstore)
+ (goto-char (point-min))
+ (when (looking-at ";;; public entries")
+ (forward-line)
+ (plstore--set-alist plstore (read (point-marker)))
+ (forward-sexp)
+ (forward-char)
+ (when (looking-at ";;; secret entries")
+ (forward-line)
+ (plstore--set-encrypted-data plstore (read (point-marker))))
+ (plstore--merge-secret plstore)))
;;;###autoload
(defun plstore-open (file)
"Create a plstore instance associated with FILE."
- (let ((store (vector
- (find-file-noselect file)
- nil ;plist (plist)
- nil ;encrypted data (string)
- nil ;secret plist (plist)
- nil ;merged plist (plist)
- )))
- (plstore-revert store)
- store))
+ (let* ((filename (file-truename file))
+ (buffer (or (find-buffer-visiting filename)
+ (generate-new-buffer (format " plstore %s" filename))))
+ (store (plstore--make buffer)))
+ (with-current-buffer buffer
+ ;; In the future plstore will provide a major mode called
+ ;; `plstore-mode' to edit PLSTORE files.
+ (if (eq major-mode 'plstore-mode)
+ (error "%s is opened for editing; kill the buffer first" file))
+ (erase-buffer)
+ (condition-case nil
+ (insert-file-contents-literally file)
+ (error))
+ (setq buffer-file-name (file-truename file))
+ (set-buffer-modified-p nil)
+ (plstore--init-from-buffer store)
+ store)))
(defun plstore-revert (plstore)
"Replace current data in PLSTORE with the file on disk."
(with-current-buffer (plstore--get-buffer plstore)
- ;; make the buffer invisible from user
- (rename-buffer (format " plstore %s" (buffer-file-name)))
- (goto-char (point-min))
- (when (looking-at ";;; public entries\n")
- (forward-line)
- (plstore--set-alist plstore (read (point-marker)))
- (forward-sexp)
- (forward-char)
- (when (looking-at ";;; secret entries\n")
- (forward-line)
- (plstore--set-encrypted-data plstore (read (point-marker))))
- (plstore--merge-secret plstore))))
+ (revert-buffer t t)
+ (plstore--init-from-buffer plstore)))
(defun plstore-close (plstore)
"Destroy a plstore instance PLSTORE."
(cons (cons name secret-plist) (plstore--get-secret-alist plstore)))))
(plstore--merge-secret plstore)))
+(defun plstore-delete (plstore name)
+ "Delete an entry with NAME from PLSTORE."
+ (let ((entry (assoc name (plstore--get-alist plstore))))
+ (if entry
+ (plstore--set-alist
+ plstore
+ (delq entry (plstore--get-alist plstore))))
+ (setq entry (assoc name (plstore--get-secret-alist plstore)))
+ (if entry
+ (plstore--set-secret-alist
+ plstore
+ (delq entry (plstore--get-secret-alist plstore))))
+ (setq entry (assoc name (plstore--get-merged-alist plstore)))
+ (if entry
+ (plstore--set-merged-alist
+ plstore
+ (delq entry (plstore--get-merged-alist plstore))))))
+
(defvar pp-escape-newlines)
+(defun plstore--insert-buffer (plstore)
+ (insert ";;; public entries -*- mode: plstore -*- \n"
+ (pp-to-string (plstore--get-alist plstore)))
+ (if (plstore--get-secret-alist plstore)
+ (let ((context (epg-make-context 'OpenPGP))
+ (pp-escape-newlines nil)
+ (recipients
+ (cond
+ ((listp plstore-encrypt-to) plstore-encrypt-to)
+ ((stringp plstore-encrypt-to) (list plstore-encrypt-to))))
+ cipher)
+ (epg-context-set-armor context t)
+ (epg-context-set-passphrase-callback
+ context
+ (cons #'plstore-passphrase-callback-function
+ plstore))
+ (setq cipher (epg-encrypt-string
+ context
+ (pp-to-string
+ (plstore--get-secret-alist plstore))
+ (if (or (eq plstore-select-keys t)
+ (and (null plstore-select-keys)
+ (not (local-variable-p 'plstore-encrypt-to
+ (current-buffer)))))
+ (epa-select-keys
+ context
+ "Select recipients for encryption.
+If no one is selected, symmetric encryption will be performed. "
+ recipients)
+ (if plstore-encrypt-to
+ (epg-list-keys context recipients)))))
+ (goto-char (point-max))
+ (insert ";;; secret entries\n" (pp-to-string cipher)))))
+
(defun plstore-save (plstore)
"Save the contents of PLSTORE associated with a FILE."
(with-current-buffer (plstore--get-buffer plstore)
(erase-buffer)
- (insert ";;; public entries\n" (pp-to-string (plstore--get-alist plstore)))
- (if (plstore--get-secret-alist plstore)
- (let ((context (epg-make-context 'OpenPGP))
- (pp-escape-newlines nil)
- cipher)
- (epg-context-set-armor context t)
- (epg-context-set-passphrase-callback
- context
- (cons #'plstore-passphrase-callback-function
- plstore))
- (setq cipher (epg-encrypt-string context
- (pp-to-string
- (plstore--get-secret-alist plstore))
- nil))
- (insert ";;; secret entries\n" (pp-to-string cipher))))
+ (plstore--insert-buffer plstore)
(save-buffer)))
(provide 'plstore)