2005-07-24 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
	* mml2015-pgg-sign(): determine the actual hash-algorithm instead
	  of using 'sha1' everytime. Else, signatures for non-sha1 hashes
	  can not be verified with Thunderbird/Enigmail.

          Currently, this change was applied to mml2015-pgg-sign()
          only. The other mml2015-*-sign() functions should get it
          also, but I did not get them to run and could not test the
          change therefore.

        * ensc/mml2015-pgg-signinfo(): added; it uses the specially
          formated SIG_CREATED lines of gnupg to determine the used
          algorithms plus some other (currently unused)
          information. Perhaps, this function should be moved into
          'pgg.el'.

--- gnus/lisp/mml2015.el.orig	2005-07-24 17:30:50.000000000 +0200
+++ gnus/lisp/mml2015.el	2005-07-24 17:32:05.000000000 +0200
@@ -74,6 +74,24 @@
        mml2015-pgg-clear-decrypt))
   "Alist of PGP/MIME functions.")
 
+(defconst mml2015-gpg-pubkeyalgo-alist
+  '(( "1"  .  "rsa")
+    ( "2"  .  "rsa-e")
+    ( "3"  .  "rsa-s")
+    ("16"  .  "elg-e")
+    ("17"  .  "dsa")
+    ("18"  .  "ecliptic-curve")
+    ("19"  .  "ecdsa")
+    ("21"  .  "dh")))
+
+(defconst mml2015-gpg-hashalgo-alist
+  '(( "1"  .  "md5")
+    ( "2"  .  "sha1")
+    ( "3"  .  "ripemd160")
+    ( "8"  .  "sha256")
+    ( "9"  .  "sha386")
+    ("10"  .  "sha512")))
+
 (defvar mml2015-result-buffer nil)
 
 (defcustom mml2015-unabbrev-trust-alist
@@ -558,6 +576,14 @@
 	(unless (> (point-max) (point-min))
 	  (pop-to-buffer mml2015-result-buffer)
 	  (error "Sign error")))
+
+      (goto-char (point-min mml2015-result-buffer) mml2015-result-buffer)
+      (setq gpg-sign-hash-algostr
+	    (or (if (re-search-forward "^\\[\\S-+:\\] SIG_CREATED \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\)"
+				       nil t 1 mml2015-result-buffer)
+		    (assoc (match-string 3) 'mml2015-gpg-algo-alist))
+		"sha1"))
+      
       (goto-char (point-min))
       (while (re-search-forward "\r+$" nil t)
 	(replace-match "" t t))
@@ -565,8 +591,8 @@
       (goto-char (point-min))
       (insert (format "Content-Type: multipart/signed; boundary=\"%s\";\n"
 		      boundary))
-      ;;; FIXME: what is the micalg?
-      (insert "\tmicalg=pgp-sha1; protocol=\"application/pgp-signature\"\n")
+      (insert (format "\tmicalg=pgp-%s; protocol=\"application/pgp-signature\"\n"
+		      gpg-sign-hash-algostr))
       (insert (format "\n--%s\n" boundary))
       (goto-char (point-max))
       (insert (format "\n--%s\n" boundary))
@@ -803,6 +829,36 @@
       (mm-set-handle-multipart-parameter
        mm-security-handle 'gnus-info "Failed"))))
 
+(defun ensc/match-buffer-string (num buf)
+  (buffer-substring (match-beginning num)
+		    (match-end num)
+		    buf))
+
+(defun ensc/mml2015-pgg-signinfo ()
+  "Returns a tuple consisting of [<pubkey algo>, <hash-algo>, <class>, <timestamp>,
+<fingerprint>, <pubkey algo raw>, <hash algo raw>]. It expects that
+the information in 'mml2015-result-buffer are using the encoding
+described in the DETAILS file of the gnupg package."
+  
+  (goto-char (point-min mml2015-result-buffer) mml2015-result-buffer)
+  (if (re-search-forward "^\\[\\S-+:\\] SIG_CREATED \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\) \\(\\S-+\\)"
+			 nil t 1 mml2015-result-buffer)
+      (list (or (cdr (assoc (ensc/match-buffer-string 2 mml2015-result-buffer)
+			    mml2015-gpg-pubkeyalgo-alist))
+		("rsa"))
+	    (or (cdr (assoc (ensc/match-buffer-string 3 mml2015-result-buffer)
+			     mml2015-gpg-hashalgo-alist))
+		("sha1"))
+	    (ensc/match-buffer-string 4 mml2015-result-buffer)	; class
+	    (ensc/match-buffer-string 5 mml2015-result-buffer)	; timestamp
+	    (ensc/match-buffer-string 6 mml2015-result-buffer)	; fingerprint
+	    (ensc/match-buffer-string 2 mml2015-result-buffer)	; raw pubkey-algo
+	    (ensc/match-buffer-string 3 mml2015-result-buffer)	; raw hash-algo
+	    )
+    (list "rsa" "sha1" "0" (current-time) nil "1" "2")))
+
+	    
+      
 (defun mml2015-pgg-sign (cont)
   (let ((pgg-errors-buffer mml2015-result-buffer)
 	(boundary (mml-compute-boundary cont))
@@ -814,8 +870,8 @@
     (goto-char (point-min))
     (insert (format "Content-Type: multipart/signed; boundary=\"%s\";\n"
 		    boundary))
-      ;;; FIXME: what is the micalg?
-    (insert "\tmicalg=pgp-sha1; protocol=\"application/pgp-signature\"\n")
+    (insert (format "\tmicalg=pgp-%s; protocol=\"application/pgp-signature\"\n"
+		      (nth 1 (ensc/mml2015-pgg-signinfo))))
     (insert (format "\n--%s\n" boundary))
     (goto-char (point-max))
     (insert (format "\n--%s\n" boundary))