From b4af0ab4cf8795dca57e48eb1b78d69359a874c3 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fw@deneb.enyo.de>
Date: Sun, 18 May 2008 15:13:11 +0200
Subject: [PATCH] Keep track of the SSH key type and report it

---
 dowkd.in | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/dowkd.in b/dowkd.in
index 801d77c..1339e79 100644
--- a/dowkd.in
+++ b/dowkd.in
@@ -145,16 +145,20 @@ sub ssh_fprint_file ($) {
     return ();
 }
 
-sub ssh_fprint_check ($$$) {
-    my ($name, $length, $hash) = @_;
-    if ($length == 1024 || $length == 2048) {
+sub ssh_fprint_check ($$$$) {
+    my ($name, $type, $length, $hash) = @_;
+    $type =~ /^(?:rsa1?|dsa)\z/ or die;
+    if (($type eq 'rsa' && ($length == 1024 || $length == 2048))
+	|| ($type eq 'dsa' && $length == 1024)) {
 	$hash =~ y/://d;
 	$hash =~ s/(..)/chr(hex($1))/ge;
-	check_hash $name, $hash, "OpenSSH/$length";
+	check_hash $name, $hash, "OpenSSH/$type/$length";
+    } elsif ($type eq 'dsa') {
+	print "$name: $length bits DSA key not recommended\n";
     } else {
-	warn "$name: warning: no suitable blacklist\n";
+	warn "$name: warning: no suitable blacklist for $type/$length\n";
     }
-		      }
+}
 
 sub clear_tmp ($) {
     my $tmp = shift;
@@ -215,6 +219,14 @@ sub cleanup_ssh_auth_line ($) {
     return undef;
 }
 
+sub derive_ssh_auth_type ($) {
+    my $line = shift;
+    $line =~ /^ssh-rsa\s/ and return 'rsa';
+    $line =~ /^ssh-dss\s/ and return 'dsa';
+    $line =~ /^\d+\s/ and return 'rsa1';
+    return undef;
+}
+
 sub from_ssh_auth_line ($$$) {
     my ($tmp, $name, $line) = @_;
     chomp $line;
@@ -225,13 +237,14 @@ sub from_ssh_auth_line ($$$) {
 	$l or goto ERROR;
 	$line = $l;
     }
+    my $type = derive_ssh_auth_type $line;
 
     clear_tmp $tmp;
     print $tmp "$line\n" or die "print: $!";
     $tmp->flush or die "flush: $!";
     my ($length, $hash) = ssh_fprint_file "$tmp";
     if ($length && $hash) {
-	ssh_fprint_check "$name", $length, $hash;
+	ssh_fprint_check "$name", $type, $length, $hash;
 	return;
     }
 
-- 
2.11.4.GIT