2010-03-27 Teodor Zlatanov <tzz@lifelogs.com>

 * auth-source.el (auth-sources): Change default to be simpler.  Explain
 about Secret Service API sources.  Improve Customize options.
 (auth-source-pick): Change to accept any number of search parameters.
 Implement fallbacks iteratively, not recursively.  Add scoring on the
 second pass and sort by score.  Call Secret Service API when needed.
 (auth-source-user-or-password): Use it.  Call Secret Service API
 directly when needed to get the user name and the password.

2 files changed, 200 insertions, 56 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 20a8cb63997..ecbce02ad85 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,13 @@
+2010-03-27  Teodor Zlatanov  <tzz@lifelogs.com>
+
+        * auth-source.el (auth-sources): Change default to be simpler.  Explain
+        about Secret Service API sources.  Improve Customize options.
+        (auth-source-pick): Change to accept any number of search parameters.
+        Implement fallbacks iteratively, not recursively.  Add scoring on the
+        second pass and sort by score.  Call Secret Service API when needed.
+        (auth-source-user-or-password): Use it.  Call Secret Service API
+        directly when needed to get the user name and the password.
+
 2010-03-24  Juanma Barranquero  <lekktu@gmail.com>
 
         * message.el (message-interactive): Doc fix.
diff --git a/lisp/gnus/auth-source.el b/lisp/gnus/auth-source.el
index 3b0d700a86f..8c59aee9714 100644
--- a/lisp/gnus/auth-source.el
+++ b/lisp/gnus/auth-source.el
@@ -38,6 +38,7 @@
 (autoload 'secrets-search-items "secrets")
 (autoload 'secrets-get-alias "secrets")
 (autoload 'secrets-get-attribute "secrets")
+(autoload 'secrets-get-secret "secrets")
 
 (defgroup auth-source nil
   "Authentication sources."
@@ -60,6 +61,7 @@
                                (string :tag "Name")))))
 
 ;;; generate all the protocols in a format Customize can use
+;;; TODO: generate on the fly from auth-source-protocols
 (defconst auth-source-protocols-customize
   (mapcar (lambda (a)
             (let ((p (car-safe a)))
@@ -102,9 +104,13 @@ Only relevant if `auth-source-debug' is not nil."
   :version "23.2" ;; No Gnus
   :type `boolean)
 
-(defcustom auth-sources '((:source "~/.authinfo.gpg" :host t :protocol t))
+(defcustom auth-sources '((:source "~/.authinfo.gpg"))
   "List of authentication sources.
 
+The default will get login and password information from a .gpg
+file, which you should set up with the EPA/EPG packages to be
+encrypted.  See the auth.info manual for details.
+
 Each entry is the authentication type with optional properties.
 
 It's best to customize this with `M-x customize-variable' because the choices
@@ -121,27 +127,24 @@ can get pretty complex."
                                      (choice :tag "Collection to use"
                                              (string :tag "Collection name")
                                              (const :tag "Default" 'default)
-                                             (const :tag "Any" t)
-                                             (const :tag "Temporary" "session")
-                                             (string :tag "Specific session name")
-                                             (const :tag "Fallback" nil))))
-                       (const :format "" :value :host)
-                       (choice :tag "Host (machine) choice"
-                               (const :tag "Any" t)
-                               (regexp :tag "Host (machine) regular expression (TODO)")
-                               (const :tag "Fallback" nil))
-                       (const :format "" :value :protocol)
-                       (choice :tag "Protocol"
-                               (const :tag "Any" t)
-                               (const :tag "Fallback" nil)
-                               ,@auth-source-protocols-customize)
+                                             (const :tag "Login" "login")
+                                             (const :tag "Temporary" "session"))))
                        (repeat :tag "Extra Parameters" :inline t
                                (choice :tag "Extra parameter"
-                                       (list :tag "Preferred username" :inline t
-                                             (const :format "" :value :preferred-username)
+                                       (list :tag "Host (omit to match as a fallback)"
+                                             (const :format "" :value :host)
+                                             (choice :tag "Host (machine) choice"
+                                                     (const :tag "Any" t)
+                                                     (regexp :tag "Host (machine) regular expression")))
+                                       (list :tag "Protocol (omit to match as a fallback)"
+                                             (const :format "" :value :protocol)
+                                             (choice :tag "Protocol"
+                                                     (const :tag "Any" t)
+                                                     ,@auth-source-protocols-customize))
+                                       (list :tag "User  (omit to match as a fallback)" :inline t
+                                             (const :format "" :value :user)
                                              (choice :tag "Personality or username"
                                                      (const :tag "Any" t)
-                                                     (const :tag "Fallback" nil)
                                                      (string :tag "Specific user name"))))))))
 
 ;; temp for debugging
@@ -153,7 +156,7 @@ can get pretty complex."
 ;; (customize-variable 'auth-source-protocols)
 ;; (setq auth-source-protocols nil)
 ;; (format "%S" auth-source-protocols)
-;; (auth-source-pick "a" 'imap)
+;; (auth-source-pick nil :host "a" :port 'imap)
 ;; (auth-source-user-or-password "login" "imap.myhost.com" 'imap)
 ;; (auth-source-user-or-password "password" "imap.myhost.com" 'imap)
 ;; (auth-source-user-or-password-imap "login" "imap.myhost.com")
@@ -173,27 +176,121 @@ can get pretty complex."
                     'message)))
       (apply logger msg))))
 
-(defun auth-source-pick (host protocol &optional fallback)
-  "Parse `auth-sources' for HOST, and PROTOCOL matches.
+;; (auth-source-pick nil :host "any" :protocol 'imap :user "joe")
+;; (auth-source-pick t :host "any" :protocol 'imap :user "joe")
+;; (setq auth-sources '((:source (:secrets default) :host t :protocol t :user "joe") 
+;;                   (:source (:secrets "session") :host t :protocol t :user "joe") 
+;;                   (:source (:secrets "login") :host t :protocol t)
+;;                   (:source "~/.authinfo.gpg" :host t :protocol t)))
+
+;; (setq auth-sources '((:source (:secrets default) :host t :protocol t :user "joe") 
+;;                   (:source (:secrets "session") :host t :protocol t :user "joe") 
+;;                   (:source (:secrets "login") :host t :protocol t)
+;;                   ))
+
+;; (setq auth-sources '((:source "~/.authinfo.gpg" :host t :protocol t)))
+
+(defun auth-source-pick (&rest spec)
+  "Parse `auth-sources' for matches of the SPEC plist.
+
+Common keys are :host, :protocol, and :user.  A value of t in
+SPEC means to always succeed in the match.  A string value is
+matched as a regex.
 
-Returns fallback choices (where PROTOCOL or HOST are nil) with FALLBACK t."
-  (interactive "sHost: \nsProtocol: \n") ;for testing
+The first pass skips fallback choices.  If no choices are found
+on the first pass, a second pass is made including the fallback
+choices.
+
+For string (filename) sources, fallback choices are those where
+PROTOCOL or HOST are nil.
+
+For secrets.el collections, the :host and :protocol keys are not
+checked for fallback choices."
   (let (choices)
-    (dolist (choice auth-sources)
-      (let ((h (plist-get choice :host))
-            (p (plist-get choice :protocol)))
-        (when (and
-               (or (equal t h)
-                   (and (stringp h) (string-match h host))
-                   (and fallback (equal h nil)))
-               (or (equal t p)
-                   (and (symbolp p) (equal p protocol))
-                   (and fallback (equal p nil))))
-          (push choice choices))))
-    (if choices
-        choices
-      (unless fallback
-        (auth-source-pick host protocol t)))))
+    (dolist (fallback '(nil t))
+      (let ((keys (loop for i below (length spec) by 2
+                        collect (nth i spec)))
+            (default-session-fallback "login"))
+        (dolist (choice auth-sources)
+          (let* ((s (plist-get choice :source))
+                 ;; this is only set for Secret Service API specs (see secrets.el)
+                 (coll (plist-get s :secrets))
+                 (score 0))
+            (cond
+             (coll                              ; use secrets.el here
+              (when (eq coll 'default)
+                (setq coll (secrets-get-alias "default"))
+                (unless coll 
+                  (auth-source-do-debug
+                   "No 'default' alias.  Trying collection '%s'."
+                   default-session-fallback)
+                  (setq coll default-session-fallback)))
+              (let* ((coll-search (cond
+                                   ((stringp coll) coll)
+                                   
+                                   ;; when the collection is nil:
+                                   ;; in fallback mode, accept it as any
+                                   ;; otherwise, hope to fail
+                                   ((null coll) (if fallback
+                                                    nil
+                                                  " *fallback-fail*"))))
+                     ;; assemble a search query for secrets-search-items
+                     ;; in fallback mode, host and protocol are not checked
+                     (other-search (loop for k
+                                         in (if fallback
+                                                (remove :host 
+                                                        (remove :protocol keys))
+                                              keys)
+                                         append (list
+                                                 k
+                                                 ;; convert symbols to a string
+                                                 (let ((v (plist-get spec k)))
+                                                   (if (stringp v)
+                                                       v
+                                                     (prin1-to-string v))))))
+                     ;; the score is based on how exact the search was, 
+                     ;; plus base score = 1 for any match
+                     (score (1+ (length other-search)))
+                     (results (apply 'secrets-search-items
+                                     coll-search
+                                     other-search)))
+                (auth-source-do-debug
+                 "auth-source-pick: got items %s in collection '%s' + %s"
+                 results coll-search other-search)
+                ;; put the results in the choices variable
+                (dolist (result results)
+                  (setq choices (cons (list score
+                                            `(:source secrets
+                                                      :item ,result
+                                                      :collection ,coll
+                                                      :search ,coll-search
+                                                      ,@other-search))
+                                      choices)))))
+             ;; this is any non-secrets spec (currently means a string filename)
+             (t
+              (let ((match t))
+                (dolist (k keys)
+                  (let* ((v (plist-get spec k))
+                         (choicev (plist-get choice k)))
+                    (setq match
+                          (and match
+                               (or (eq t choicev) ; source always matches spec key
+                                   ;; source key gives regex to match against spec
+                                   (and (stringp choicev) (string-match choicev v))
+                                   ;; source key gives symbol to match against spec
+                                   (and (symbolp choicev) (eq choicev v))
+                                   ;; in fallback mode, missing source key is OK
+                                   fallback)))
+                    (when match (incf score)))) ; increment the score for each match
+
+                ;; now if the whole iteration resulted in a match:
+                (when match
+                  (setq choices (cons (list score choice) choices))))))))
+        ;; when there were matches, skip the second pass
+        (when choices (return choices))))
+
+      ;; return the results sorted by score
+      (mapcar 'cadr (sort choices (lambda (x y) (> (car x) (car y)))))))
 
 (defun auth-source-forget-user-or-password (mode host protocol)
   (interactive "slogin/password: \nsHost: \nsProtocol: \n") ;for testing
@@ -204,44 +301,81 @@ Returns fallback choices (where PROTOCOL or HOST are nil) with FALLBACK t."
   (interactive)
   (setq auth-source-cache (make-hash-table :test 'equal)))
 
-(defun auth-source-user-or-password (mode host protocol)
+;; (progn
+;;   (auth-source-forget-all-cached)
+;;   (list
+;;    (auth-source-user-or-password '("login" "password") "imap.myhost.com" "other")
+;;    (auth-source-user-or-password '("login" "password") "imap.myhost.com" "other" "tzz")
+;;    (auth-source-user-or-password '("login" "password") "imap.myhost.com" "other" "joe")))
+
+(defun auth-source-user-or-password (mode host protocol &optional username)
   "Find MODE (string or list of strings) matching HOST and PROTOCOL.
+
+USERNAME is optional and will be used as \"login\" in a search
+across the Secret Service API (see secrets.el) if the resulting
+items don't have a username.  This means that if you search for
+username \"joe\" and it matches an item but the item doesn't have
+a :user attribute, the username \"joe\" will be returned.
+
 MODE can be \"login\" or \"password\" for example."
   (auth-source-do-debug
-   "auth-source-user-or-password: get %s for %s (%s)"
-   mode host protocol)
+   "auth-source-user-or-password: get %s for %s (%s) + user=%s"
+   mode host protocol username)
   (let* ((listy (listp mode))
          (mode (if listy mode (list mode)))
-         (cname (format "%s %s:%s" mode host protocol))
+         (extras (when username `(:user ,username)))
+         (cname (format "%s %s:%s %s" mode host protocol extras))
+         (search (list :host host :protocol protocol))
+         (search (if username (append search (list :user username)) search))
          (found (gethash cname auth-source-cache)))
     (if found
         (progn
           (auth-source-do-debug
-           "auth-source-user-or-password: cached %s=%s for %s (%s)"
+           "auth-source-user-or-password: cached %s=%s for %s (%s) + %s"
            mode
            ;; don't show the password
-           (if (and (member "password" mode) auth-source-hide-passwords) "SECRET" found)
-           host protocol)
-          found)
-      (dolist (choice (auth-source-pick host protocol))
-        (setq found (netrc-machine-user-or-password
-                     mode
-                     (plist-get choice :source)
-                     (list host)
-                     (list (format "%s" protocol))
-                     (auth-source-protocol-defaults protocol)))
+           (if (and (member "password" mode) auth-source-hide-passwords)
+               "SECRET"
+             found)
+           host protocol extras)
+          found)                        ; return the found data
+      ;; else, if not found
+      (dolist (choice (apply 'auth-source-pick search))
+        (setq found (cond
+                     ;; the secrets.el spec
+                     ((eq (plist-get choice :source) 'secrets)
+                      (let ((coll (plist-get choice :search))
+                            (item (plist-get choice :item)))
+                        (mapcar (lambda (m)
+                                  (if (equal "password" m)
+                                      (secrets-get-secret coll item)
+                                    ;; the user name is either
+                                    (or
+                                     ;; the secret's attribute :user, or
+                                     (secrets-get-attribute coll item :user)
+                                     ;; the originally requested :user
+                                     username
+                                     "unknown-user")))
+                                mode)))
+                     (t         ; anything else is netrc
+                      (netrc-machine-user-or-password
+                       mode
+                       (plist-get choice :source)
+                       (list host)
+                       (list (format "%s" protocol))
+                       (auth-source-protocol-defaults protocol)))))
         (when found
           (auth-source-do-debug
-           "auth-source-user-or-password: found %s=%s for %s (%s)"
+           "auth-source-user-or-password: found %s=%s for %s (%s) + %s"
            mode
            ;; don't show the password
            (if (and (member "password" mode) auth-source-hide-passwords) "SECRET" found)
-           host protocol)
+           host protocol extras)
           (setq found (if listy found (car-safe found)))
           (when auth-source-do-cache
             (puthash cname found auth-source-cache)))
         (return found)))))
-
+  
 (defun auth-source-protocol-defaults (protocol)
   "Return a list of default ports and names for PROTOCOL."
   (cdr-safe (assoc protocol auth-source-protocols)))