From 2c6e956e0a8e4153b09df7fa2543dbf6d5f183a3 Mon Sep 17 00:00:00 2001
From: Dominik Csapak <d.csapak@proxmox.com>
Date: Fri, 13 Mar 2020 13:18:45 +0100
Subject: [PATCH] Auth/LDAP: add get_{users, groups} subs for syncing

this adds the subs which actually query the LDAP for users/groups
and returns the value in format which makes it easy to insert
in our parsed user.cfg

when we find a user/groupname which cannot be in our config,
we warn the verification error

for groups, we append "-$realm" to the groupname, to lower the chance of
accidental overwriting of existing groups (this will be documented
in the api call since it technically does not prevent overwriting, just
makes it more unlikely)

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 PVE/Auth/LDAP.pm | 132 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)

diff --git a/PVE/Auth/LDAP.pm b/PVE/Auth/LDAP.pm
index bcd90d7..3dd4ae6 100755
--- a/PVE/Auth/LDAP.pm
+++ b/PVE/Auth/LDAP.pm
@@ -190,6 +190,138 @@ sub connect_and_bind {
     return $ldap;
 }
 
+# returns:
+# {
+#     'username@realm' => {
+# 	'attr1' => 'value1',
+# 	'attr2' => 'value2',
+# 	...
+#     },
+#     ...
+# }
+#
+# or in list context:
+# (
+#     {
+# 	'username@realm' => {
+# 	    'attr1' => 'value1',
+# 	    'attr2' => 'value2',
+# 	    ...
+# 	},
+# 	...
+#     },
+#     {
+# 	'uid=username,dc=....' => 'username@realm',
+# 	...
+#     }
+# )
+# the map of dn->username is needed for group membership sync
+sub get_users {
+    my ($class, $config, $realm) = @_;
+
+    my $ldap = $class->connect_and_bind($config, $realm);
+
+    my $user_name_attr = $config->{user_attr} // 'uid';
+    my $ldap_attribute_map = {
+	$user_name_attr => 'username',
+	enable => 'enable',
+	expire => 'expire',
+	firstname => 'firstname',
+	lastname => 'lastname',
+	email => 'email',
+	comment => 'comment',
+	keys => 'keys',
+    };
+
+    foreach my $attr (PVE::Tools::split_list($config->{sync_attributes})) {
+	my ($ours, $ldap) = ($attr =~ m/^\s*(\w+)=(.*)\s*$/);
+	$ldap_attribute_map->{$ldap} = $ours;
+    }
+
+    my $filter = $config->{filter};
+    my $basedn = $config->{base_dn};
+
+    $config->{user_classes} //= 'inetorgperson, posixaccount, person, user';
+    my $classes = [PVE::Tools::split_list($config->{user_classes})];
+
+    my $users = PVE::LDAP::query_users($ldap, $filter, [keys %$ldap_attribute_map], $basedn, $classes);
+
+    my $ret = {};
+    my $dnmap = {};
+
+    foreach my $user (@$users) {
+	my $user_attributes = $user->{attributes};
+	my $userid = $user_attributes->{$user_name_attr}->[0];
+	my $username = "$userid\@$realm";
+
+	# we cannot sync usernames that do not meet our criteria
+	eval { PVE::Auth::Plugin::verify_username($username) };
+	if (my $err = $@) {
+	    warn "$err";
+	    next;
+	}
+
+	$ret->{$username} = {};
+
+	foreach my $attr (keys %$user_attributes) {
+	    if (my $ours = $ldap_attribute_map->{$attr}) {
+		$ret->{$username}->{$ours} = $user_attributes->{$attr}->[0];
+	    }
+	}
+
+	if (wantarray) {
+	    my $dn = $user->{dn};
+	    $dnmap->{$dn} = $username;
+	}
+    }
+
+    return wantarray ? ($ret, $dnmap) : $ret;
+}
+
+# needs a map for dn -> username, we get this from the get_users call
+# otherwise we cannot determine the group membership
+sub get_groups {
+    my ($class, $config, $realm, $dnmap) = @_;
+
+    my $filter = $config->{group_filter};
+    my $basedn = $config->{group_dn} // $config->{base_dn};
+    my $attr = $config->{group_name_attr};
+    $config->{group_classes} //= 'groupOfNames, group, univentionGroup, ipausergroup';
+    my $classes = [PVE::Tools::split_list($config->{group_classes})];
+
+    my $ldap = $class->connect_and_bind($config, $realm);
+
+    my $groups = PVE::LDAP::query_groups($ldap, $basedn, $classes, $filter, $attr);
+
+    my $ret = {};
+
+    foreach my $group (@$groups) {
+	my $name = $group->{name};
+	if (!$name && $group->{dn} =~ m/^[^=]+=([^,]+),/){
+	    $name = PVE::Tools::trim($1);
+	}
+	if ($name) {
+	    $name .= "-$realm";
+
+	    # we cannot sync groups that do not meet our criteria
+	    eval { PVE::AccessControl::verify_groupname($name) };
+	    if (my $err = $@) {
+		warn "$err";
+		next;
+	    }
+
+	    $ret->{$name} = { users => {} };
+	    foreach my $member (@{$group->{members}}) {
+		if (my $user = $dnmap->{$member}) {
+		    $ret->{$name}->{users}->{$user} = 1;
+		}
+	    }
+	}
+    }
+
+    return $ret;
+}
+
 sub authenticate_user {
     my ($class, $config, $realm, $username, $password) = @_;
 
-- 
2.39.2