Fix for #4070

- Add support for a new configuration option "dns-lookup" to
  control weither DNS lookups shall happen at all
- Find servers from DNS always if the dnslookup option is true. This
  way these servers can be used as fallback even if a server is
  configured. Otherwise DNS lookups do not happen if a server is
  configured in the client configuration.
- Support multiple servers in the configuration file.
- Use a global for tracking the registration tries, because
  otherwise the used server will not be exchanged, because
  the try counter gets reset everytime a new register event
  is yielded
- Minor bugfix: Do not try to compare $res to "0" if $res is not
  defined.

git-svn-id: https://oss.gonicus.de/repositories/gosa/branches/2.6-lhm@16397 594d385d-05f5-0310-b6e9-bd551577e9d8

diff --git a/trunk/gosa-si/gosa-si-client b/trunk/gosa-si/gosa-si-client
index 45a3b29389495b436906048905a35af8769e0b53..db4773b465f9018d0a5c793f0daea58cf82a991f 100755 (executable)
--- a/trunk/gosa-si/gosa-si-client
+++ b/trunk/gosa-si/gosa-si-client
@@ -60,6 +60,7 @@ my @servers;
 my $gotoHardwareChecksum;
 my $gosa_si_client_fifo;
 my %files_to_watch;
+my $servers_string;
 $verbose= 1;
 
 # globalise variables which are used in imported events
@@ -73,9 +74,13 @@ our $client_mac_address;
 our $client_dnsname;
 our $client_force_hostname;
 our $server_key;
+our $opts_dnslookup;
 
 # default variables
 our $REGISTERED = 0;
+our $REGISTRATION_IN_PROGRESS = 0;
+our $REGISTRATION_TRIES = 0;
+our $FAILED_CRYPTO = 0;
 
 # path to fifo for non-gosa-si-client messages to gosa-si-server
 $gosa_si_client_fifo = "/var/run/gosa-si-client.socket";
@@ -86,6 +91,10 @@ $gosa_si_client_fifo = "/var/run/gosa-si-client.socket";
 my $delay_set_time = 10;
 our $prg= basename($0);
 
+# Threshold for the max number of wrong crypted packages, when triggered
+# a new server is choosen
+my $max_failed_crypto_messages = 5;
+
 # all n seconds the client reports logged_in users to gosa-si-server
 my $trigger_logged_in_users_report_delay = 600;
 
@@ -114,11 +123,12 @@ my $fai_log_dir = "/var/log/fai";
      "force-hostname"    => [\$client_force_hostname, "false"],
     },
 "server" => {
-    "ip"          => [\$server_ip, "127.0.0.1"],
+    "ip"          => [\$servers_string, "127.0.0.1"],
     "port"         => [\$server_port, "20081"],
     "key"          => [\$server_key, ""],
     "timeout"      => [\$server_timeout, 10],
     "key-lifetime" => [\$server_key_lifetime, 600], 
+    "dns-lookup"           => [\$opts_dnslookup, "true"],
     },
 
 );
@@ -534,14 +544,15 @@ sub open_socket {
 #===============================================================================
 sub register_at_gosa_si_server {
   my ($kernel) = $_[KERNEL];
-  my $try_to_register = 0;
-  
+
        # if client is already registered, stop registration process    
        if ($REGISTERED) {
                $kernel->delay('register_at_gosa_si_server');
 
        # client is not registered, start registration process
        } else {
+        $REGISTRATION_IN_PROGRESS = 1;
+
                # clear all other triggered events and wait till registration was successful
        $kernel->delay('trigger_new_key');
 
@@ -550,21 +561,20 @@ sub register_at_gosa_si_server {
 
        my $events = join( ",", keys %{$event_hash} );
        while(1) {
-            $try_to_register++;
-
-                       # after one complete round through all server, stop trying to register           
-            if( $try_to_register > @servers )  { last; }
+            $REGISTRATION_TRIES++;
 
             # fetch first gosa-si-server from @servers
             # append shifted gosa-si-server at the end of @servers, so looking for servers never stop if
             # a registration never occured
             my $server = shift(@servers);
-            push( @servers, $server );
+            push(@servers, $server);
+            ($server_ip = $server) =~ s/:.*$//;
+            $server_address = $server;
 
             # Check if our ip is resolvable - if not: don't try to register
                        if(!(defined($server) && $server =~ m/^[0-9\.]*?:.*$/)) {
                                &main::daemon_log("ERROR: Server with address '".defined($server)?$server:""."' is invalid!", 1);
-                               if (length(@servers) == 1) {
+                               if (scalar(@servers) == 1) {
                                        &main::daemon_log("ERROR: No valid servers found!", 1);
                                        exit(1);
                                }
@@ -608,9 +618,9 @@ sub register_at_gosa_si_server {
                        my $res = &send_msg_hash_to_target($register_hash, $server, $default_server_key);
 
                        # if delivery of registration msg succeed
-                       if($res eq "0") {
+                       if(defined($res) and $res eq "0") {
                        # reset try_to_register
-                               $try_to_register = 0;
+                               $REGISTRATION_TRIES = 0;
 
                        # Set fixed client address and mac address
                                $client_ip= &get_local_ip_for_remote_ip(sprintf("%s", $server =~ /^([0-9\.]*?):.*$/));
@@ -628,7 +638,7 @@ sub register_at_gosa_si_server {
 
     } # end of while
        # one circle through all servers finished and no registration succeed
-       if ( $try_to_register >= @servers )  {
+       if ( $REGISTRATION_TRIES >= (scalar(@servers)) )  {
                        &write_to_file("gosa-si-no-server-available", $fai_logpath);
                        $kernel->delay_set('register_at_gosa_si_server', $delay_set_time);
        
@@ -1024,9 +1034,17 @@ sub server_input {
 
                        # if client is alread in a registration process, that means not registered, do nothing
                        # if not, cause re-registration
-                       if (not $REGISTERED) {
+                       if ($REGISTRATION_IN_PROGRESS) {
                                &daemon_log("WARNING: gosa-si-client is already in a registration process so ignore this message", 3);
                        } else {
+                if ($FAILED_CRYPTO > $max_failed_crypto_messages) {
+                    # Force usage of a new server
+                    daemon_log("Failed to decrypt a total of $max_failed_crypto_messages messages from the server. Trying to switch to another one", 3);
+                    $REGISTRATION_TRIES = $max_failed_crypto_messages;
+                    my $server = shift(@servers);
+                    push(@servers, $server);
+                }
+                $FAILED_CRYPTO++;
                                $REGISTERED = 0;
                                $kernel->post('client_session', 'register_at_gosa_si_server');
                        }
@@ -1038,6 +1056,9 @@ sub server_input {
     ######################
     # process incoming msg
     if( $error == 0 ) {
+        # Reset failed crypto messages state
+        $FAILED_CRYPTO = 0;
+
         my $header = @{$msg_hash->{header}}[0];
         my $source = @{$msg_hash->{source}}[0];
 
@@ -1067,6 +1088,7 @@ sub server_input {
             if( $answer =~ "<header>registered</header>") {
                 # set registered flag to true to stop sending further registered msgs
                 $REGISTERED = 1;
+                $REGISTRATION_IN_PROGRESS = 0;
             } 
             else {
                 $answer =~ /<header>(\S+)<\/header>/;
@@ -1087,6 +1109,91 @@ sub server_input {
     return;
 }
 
+sub find_servers {
+    # add gosa-si-server address from config file at first position of server list
+    my $server_check_cfg = Config::IniFiles->new( -file => $cfg_file );
+
+    # Parse servers string
+    my @conf_servers = split(',', $servers_string);
+
+    # Now search for fallback servers in the configuration
+    foreach my $cur_server (@conf_servers) {
+        # Remove spaces from the IP
+        $cur_server =~ s/\s//g;
+
+        my $ip = $cur_server;
+        if(not $cur_server =~ /^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/) {
+            my $ip_address = inet_ntoa(scalar gethostbyname($ip));
+            if(defined($ip_address) && $ip_address =~ /^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}/) {
+                # Write ip address to $server_ip variable
+                $ip = $ip_address;
+            }
+        }
+        
+        my $server_addr = sprintf("%s:%s", $ip, $server_port);
+        if (not grep { $_ eq $server_addr } @servers) {
+           push(@servers, $server_addr);
+        }
+    }
+
+    my $servers_string = join(", ", @servers);
+    daemon_log("INFO: found servers in configuration file: $servers_string", 1);
+
+    # Last but not least search for fallback servers in the DNS
+    if (defined($opts_dnslookup) and $opts_dnslookup eq "true") {
+        my @tmp_servers;
+        if ( !$server_domain) {
+            # Try our DNS Searchlist
+            my @domain_list = &get_dns_domains();
+            my $tmp_domains;
+            my $error_string;
+            for my $domain (@domain_list) {
+                chomp($domain);
+                ($tmp_domains, $error_string) = &get_server_addresses($domain);
+                if(@$tmp_domains) {
+                    for my $tmp_server(@$tmp_domains) {
+                        push @tmp_servers, $tmp_server;
+                    }
+                }
+            }
+
+            if (0 == @tmp_servers) {
+                daemon_log("INFO: No servers found in DNS.", 1);
+            }
+            else {
+                my $servers_string = join(", ", @tmp_servers);
+                daemon_log("INFO: found servers in DNS: $servers_string", 1);
+            }
+        } else {
+            @tmp_servers = &get_server_addresses($server_domain);
+            if( 0 == @tmp_servers ) {
+            daemon_log("INFO: No servers found in DNS for domain '$server_domain'",1);
+            } 
+        }
+
+        if ( 0 != @tmp_servers ) {
+            foreach my $server_addr (@tmp_servers) {
+                if (not grep { $_ eq $server_addr } @servers) {
+                   push(@servers, $server_addr);
+                }
+            }
+        }
+    }
+   
+    if (0 == scalar(@servers)) {
+        daemon_log("ERROR: No servers found in the configuration or DNS.", 1);
+        exit(1);
+    }
+
+    # Define first server as server_ip
+    $server_ip = $servers[0];
+
+    # prepare variables
+    if( inet_aton($server_ip) ){ $server_ip = inet_ntoa(inet_aton($server_ip)); }
+    if (defined $server_ip && defined $server_port) {
+        $server_address = $server_ip.":".$server_port;
+    }
+}
 
 #==== MAIN = main ==============================================================
 #  parse commandline options
@@ -1102,7 +1209,6 @@ GetOptions("h|help" => \&usage,
 &read_configfile($cfg_file, %cfg_defaults);
 &check_pid;
 
-
 # forward error messages to logfile
 if ( ! $foreground ) {
   open( STDIN,  '+>/dev/null' );
@@ -1196,64 +1302,11 @@ POE::Component::Server::TCP->new(
 );
 daemon_log("INFO: start socket for incoming xml messages at port '$client_port' ", 1);
 
-
-# prepare variables
-if( inet_aton($server_ip) ){ $server_ip = inet_ntoa(inet_aton($server_ip)); }
-if (defined $server_ip && defined $server_port) {
-    $server_address = $server_ip.":".$server_port;
-}
 $xml = new XML::Simple();
 $default_server_key = $server_key;
 
-
-# add gosa-si-server address from config file at first position of server list
-my $server_check_cfg = Config::IniFiles->new( -file => $cfg_file );
-my $server_check = (defined($server_check_cfg))?$server_check_cfg->val( "server", "ip"):undef;
-if( defined $server_check ) {
-       unshift(@servers, $server_address);
-       my $servers_string = join(", ", @servers);
-       daemon_log("INFO: found servers in configuration file: $servers_string", 1);
-} else {
-       my @tmp_servers;
-       if ( !$server_domain) {
-               # Try our DNS Searchlist
-               my @domain_list = &get_dns_domains();
-               my $tmp_domains;
-               my $error_string;
-               for my $domain (@domain_list) {
-                       chomp($domain);
-                       ($tmp_domains, $error_string) = &get_server_addresses($domain);
-                       if(@$tmp_domains) {
-                               for my $tmp_server(@$tmp_domains) {
-                                       push @tmp_servers, $tmp_server;
-                               }
-                       }
-               }
-               if (0 == @tmp_servers) {
-                       my $log_string = "no gosa-si-server found!";
-                       $log_string .= "\n\tdetermined domains out of /etc/resolv.conf: ".join(", ", @domain_list) if (@domain_list);
-                       $log_string .= "\n\tdetermined server addresses in domains: ".join(", ",@$tmp_domains) if (defined($tmp_domains));
-                       daemon_log("ERROR: $log_string", 1) if (defined($log_string));
-                       daemon_log("ERROR: $error_string", 1) if (defined($error_string));
-                       daemon_log("ERROR: please specify a gosa-si-server address or a domain in config file", 1);
-                       kill 2, $$;
-               }
-       } else {
-               @tmp_servers = &get_server_addresses($server_domain);
-               if( 0 == @tmp_servers ) {
-                       daemon_log("ERROR: no gosa-si-server found in DNS for domain '$server_domain'",1);
-                       daemon_log("ERROR: please specify a gosa-si-server address or a domain in config file", 1);
-                       kill 2, $$;
-               } 
-       }
-
-       foreach my $server (@tmp_servers) { 
-               unshift(@servers, $server); 
-       }
-       my $servers_string = join(", ", @servers);
-       daemon_log("INFO: found servers in DNS: $servers_string", 1);
-}
-
+# Find servers from config and DNS
+&find_servers;
 
 # open fifo for non-gosa-si-client-msgs to gosa-si-server
 POSIX::mkfifo("$gosa_si_client_fifo", "0600");