pmirror: Add option --unix-socket

pmirror/pmirror

@@ -172,7 +172,7 @@ our ($debug,$quiet,$fileop_noop,$fileop_debug,$delete);
 our ($slave_mode,$local_slave,$slave_unprivileged,
 	$lockident,$safety,$identity_file,$mkdir_slave,
 	$reduce,$force_status,$bandwidth,$allowremotefs,
-	$ssh_opt , $cksum , $nice );
+	$ssh_opt , $cksum , $nice , $unix_socket, $unix_socket_name);
 
 # globals
 
@@ -598,6 +598,7 @@ sub master
 		$allowremotefs and push @remote_opts,'--allowremotefs';
 		$cksum and push @remote_opts,'--cksum';
 		$nice and push @remote_opts,'--nice';
+		$unix_socket_name and push @remote_opts,'--socket-name',$unix_socket_name;
 
 		($slave_unprivileged or ($slave_user ne 'root')) and push @remote_opts,'--unprivileged';
 
@@ -609,6 +610,7 @@ sub master
 				,'-x',
 				'-l',$slave_user,
 				'-oFallBackToRsh=no','-oStrictHostKeyChecking=no',
+				$unix_socket_name ? ('-L',"$unix_socket_name:$unix_socket_name") : (),
 				$ssh_opt ? $ssh_opt : (),
 				$slave,
 				'/usr/local/bin/pmirror','--slave',@remote_opts,$slave_path
@@ -621,6 +623,7 @@ sub master
 		}
 
 		$debug and warn "executing @l\n";
+		$unix_socket_name and -e $unix_socket_name and unlink($unix_socket_name);
 		exec @l;
 		die "ssh: exec failed: $!\n";
 	}
@@ -634,12 +637,20 @@ sub master
 	local($, , $\)=(' ',"\n");
 
 	if ($slave) {
+		my $s_data;
 		$_=$in->getline;
 		defined $_ or die "client disconnected\n";
-		/^LISTEN (\d+)$/ or die "protokoll error; expected LISTEN got $_\n";
-		my $port=$1;
-		$debug and warn "connecting data port $slave:$port\n";
-		my $s_data=new IO::Socket::INET (PeerHost=>$slave,PeerPort=>$port,Proto=>'tcp') or die "connect to slave data port: $!\n";
+		if ($unix_socket_name) {
+			/^LISTEN (\S+)$/ or die "protocol error; expected 'LISTEN path' got '$_'\n";
+			$debug and warn "connecting to slave data port via $unix_socket_name\n";
+			$s_data=new IO::Socket::UNIX (Peer=>$unix_socket_name) or die "connect to slave data port: $!\n";
+			unlink($unix_socket_name);
+		} else {
+			/^LISTEN (\d+)$/ or die "protocol error; expected 'LISTEN port' got '$_'\n";
+			my $port=$1;
+			$debug and warn "connecting to slave data port at $slave:$port\n";
+			$s_data=new IO::Socket::INET (PeerHost=>$slave,PeerPort=>$port,Proto=>'tcp') or die "connect to slave data port: $!\n";
+		}
 		($in,$out)=($s_data,$s_data);
 	}
 
@@ -793,13 +804,21 @@ sub slave
 	chdir $slave_path or die "$slave_path: $!\n";
 
 	unless ($local_slave) {
-		my $s_listen=IO::Socket::INET->new(Listen=>1) or die "$0: $!\n";
-		my $port=$s_listen->sockport;
-
-		$out->print("LISTEN $port");
+		my $s_listen;
+		if ($unix_socket_name) {
+			-e $unix_socket_name && unlink($unix_socket_name);
+			$s_listen=IO::Socket::UNIX->new(Listen=>1,Local=>$unix_socket_name) or die "$unix_socket_name: $!\n";
+			$out->print("LISTEN $unix_socket_name");
+		} else {
+			$s_listen=IO::Socket::INET->new(Listen=>1) or die "$0: $!\n";
+			my $port=$s_listen->sockport;
+			$out->print("LISTEN $port");
+		}
 
 		my $s_data = $s_listen->accept;
-		defined $s_data or die "$!\n";
+		my $err=$!;
+		$unix_socket_name and unlink($unix_socket_name);
+		defined $s_data or die "$err\n";
 
 		($in,$out)=($s_data,$s_data);
 	}
@@ -1005,7 +1024,7 @@ INDEX_RECORD:
 use constant USAGE => <<"__EOF__";
 
 usage: $0 [options] path [node:]path
-       $0 --slave [--local-slave] path [options]
+       $0 --slave [--local-slave] [--socket-name path] path [options]
 
  options:
    --noop               dont change anything
@@ -1026,6 +1045,8 @@ usage: $0 [options] path [node:]path
    --cksum		compare existing files with CRC checksum
    --unprivileged       do not attempt to set file ownership, even if root
    --nice		EXPERIMENTAL nice
+   --unix-socket        EXPERIMENTAL establish data channel over ssh via AF unix sockets
+   --socket-name PATH   EXPERIMENTAL use PATH as name for AF unix sockets
 
 __EOF__
 
@@ -1052,6 +1073,8 @@ use constant OPTIONS => (
 	'ssh-opt=s'       => \$ssh_opt,
 	'cksum'           => \$cksum,
 	'nice'            => \$nice,
+	'unix-socket'     => \$unix_socket,
+	'socket-name=s'   => \$unix_socket_name,
 );
 
 if ($ENV{SSH_ORIGINAL_COMMAND}) {
@@ -1094,5 +1117,9 @@ if ($slave_mode) {
 		$>==0 or $slave_user='whatever';	# if we are not root, the local slave will also no be root
 	}
 
+	if ($unix_socket && !defined $unix_socket_name) {
+		$unix_socket_name=sprintf '%s/pmirror_setup_%s_%05d',($ENV{'TMPDIR'}||'/tmp'),$ENV{'USER'},int(rand(100000));
+	}
+
 	master($master_path,$slave_user,$slave,$slave_path);
 }