diff options
Diffstat (limited to 'doc/plugins/contrib/unixauth.mdwn')
| -rw-r--r-- | doc/plugins/contrib/unixauth.mdwn | 68 |
1 files changed, 60 insertions, 8 deletions
diff --git a/doc/plugins/contrib/unixauth.mdwn b/doc/plugins/contrib/unixauth.mdwn index 12f885c33..2de6fc51f 100644 --- a/doc/plugins/contrib/unixauth.mdwn +++ b/doc/plugins/contrib/unixauth.mdwn @@ -3,9 +3,36 @@ This plugin authenticates users against the Unix user database. It presents a similar UI to [[plugins/passwordauth]], but simpler, as there's no need to be able to register or change one's password. -[pwauth](http://www.unixpapa.com/pwauth/) must be installed and working. In particular, it must be configured to recognize the UID of the calling web server, or authentication will always fail. Set `pwauth_path` to the full path of your pwauth binary. +To authenticate, either [checkpassword](http://cr.yp.to/checkpwd.html) or [pwauth](http://www.unixpapa.com/pwauth/) must be installed and configured. `checkpassword` is strongly preferred. If your web server runs as an unprivileged user -- as it darn well should! -- then `checkpassword` needs to be setuid root. (Or your ikiwiki CGI wrapper, I guess, but don't do that.) Other checkpassword implementations are available, notably [checkpassword-pam](http://checkpasswd-pam.sourceforge.net/). -As [with passwordauth](/security/#index14h2), be wary of sending usernames and passwords in cleartext. Unlike with passwordauth, sniffing these credentials can get an attacker much further than mere wiki access. SSL with this plugin is a __must__. +Config variables that affect the behavior of `unixauth`: + +* `unixauth_type`: defaults to unset, can be "checkpassword" or "pwauth" +* `unixauth_command`: defaults to unset, should contain the full path and any arguments +* `unixauth_requiressl`: defaults to 1, can be 0 +* `sslcookie`: needs to be 1 if `unixauth_requiressl` is 1 (perhaps this should be done automatically?) + +__Security__: [As with passwordauth](/security/#index14h2), be wary of sending usernames and passwords in cleartext. Unlike passwordauth, sniffing `unixauth` credentials can get an attacker much further than mere wiki access. Therefore, this plugin defaults to not even _displaying_ the login form fields unless we're running under SSL. Nobody should be able to do anything remotely dumb until the admin has done at least a little thinking. After that, dumb things are always possible. ;-) + +`unixauth` tests for the presence of the `HTTPS` environment variable. `Wrapper.pm` needs to be tweaked to pass it through; without that, the plugin fails closed. + +[[!toggle id="diff" text="Wrapper.pm.diff"]] + +[[!toggleable id="diff" text=""" + + --- Wrapper.pm.orig 2008-07-29 00:09:10.000000000 -0400 + +++ Wrapper.pm + @@ -28,7 +28,7 @@ sub gen_wrapper () { #{{{ + my @envsave; + push @envsave, qw{REMOTE_ADDR QUERY_STRING REQUEST_METHOD REQUEST_URI + CONTENT_TYPE CONTENT_LENGTH GATEWAY_INTERFACE + - HTTP_COOKIE REMOTE_USER} if $config{cgi}; + + HTTP_COOKIE REMOTE_USER HTTPS} if $config{cgi}; + my $envsave=""; + foreach my $var (@envsave) { + $envsave.=<<"EOF" + +"""]] [[!toggle id="code" text="unixauth.pm"]] @@ -40,13 +67,26 @@ As [with passwordauth](/security/#index14h2), be wary of sending usernames and p } my $ret=0; - if (! exists $config{pwauth_path}) { - $config{pwauth_path}="/usr/libexec/pwauth"; + if (! exists $config{unixauth_type}) { + # admin needs to carefully think over his configuration + return 0; + } + elsif ($config{unixauth_type} eq "checkpassword") { + open UNIXAUTH, "|$config{unixauth_command} true 3<&0" or die("Could not run $config{unixauth_type}"); + print UNIXAUTH "$user\0$password\0Y123456\0"; + close UNIXAUTH; + $ret=!($?>>8); + } + elsif ($config{unixauth_type} eq "pwauth") { + open UNIXAUTH, "|$config{unixauth_command}" or die("Could not run $config{unixauth_type}"); + print UNIXAUTH "$user\n$password\n"; + close UNIXAUTH; + $ret=!($?>>8); + } + else { + # no such authentication type + return 0; } - open PWAUTH, "|$config{pwauth_path}" or die("Could not run pwauth"); - print PWAUTH "$user\n$password\n"; - close PWAUTH; - $ret=!($?>>8); if ($ret) { my $userinfo=IkiWiki::userinfo_retrieve(); @@ -69,6 +109,17 @@ As [with passwordauth](/security/#index14h2), be wary of sending usernames and p my $session=$params{session}; my $cgi=$params{cgi}; + # if not under SSL, die before even showing a login form, + # unless the admin explicitly says it's fine + if (! exists $config{unixauth_requiressl}) { + $config{unixauth_requiressl} = 1; + } + if ($config{unixauth_requiressl}) { + if ((! $config{sslcookie}) || (! exists $ENV{'HTTPS'})) { + die("SSL required to login. Contact your administrator.<br>"); + } + } + if ($form->title eq "signin") { $form->field(name => "name", required => 0); $form->field(name => "password", type => "password", required => 0); @@ -93,6 +144,7 @@ As [with passwordauth](/security/#index14h2), be wary of sending usernames and p ); } + # XXX is this reachable? looks like no elsif ($submittype eq "Login") { $form->field( name => "name", |