Unified symbol table for shell variables.

Signed-off-by: Tom Eastep <teastep@shorewall.net>

Shorewall/Perl/Shorewall/Config.pm

@@ -122,6 +122,7 @@ our %EXPORT_TAGS = ( internal => [ qw( create_temp_script
 				       qt
 				       ensure_config_path
 				       add_param
+				       add_symbol
 				       export_params
 				       get_configuration
 				       report_capabilities
@@ -560,7 +561,10 @@ use constant { PLAIN_READ          => 0,     # No read_a_line options
                NORMAL_READ         => -1     # All options
 	   };
 
+my %symbols; # Symbol table for expanding shell variables
+
 sub process_shorewallrc($$);
+sub add_symbols( \% );
 #
 # Rather than initializing globals in an INIT block or during declaration,
 # we initialize them in a function. This is done for two reasons:
@@ -952,6 +956,8 @@ sub initialize( $;$$) {
 		    SHAREDIR => '/usr/share/',
 		    CONFDIR  => '/etc/',
 		    );
+
+    %symbols = %ENV;
     #
     # If we are compiling for export, process the shorewallrc from the remote system
     #
@@ -992,6 +998,8 @@ sub initialize( $;$$) {
     }
 
     %shorewallrc1 = %shorewallrc unless $shorewallrc1;
+
+    add_symbols %shorewallrc1;
 }
 
 my @abbr = qw( Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec );
@@ -1927,12 +1935,7 @@ sub evaluate_expression( $$$ ) {
     while ( $expression =~ m( ^(.*?) \$({)? (\d+|[a-zA-Z]\w*) (?(2)}) (.*)$ )x ) {
 	my ( $first, $var, $rest ) = ( $1, $3, $4);
 
-	$val = ( exists $ENV{$var}          ? $ENV{$var}    :
+	$val = ( exists $symbols{$var}      ? $symbols{$var}    :
-		 exists $params{$var}       ? $params{$var} :
-		 exists $config{$var}       ? $config{$var} :
-		 exists $renamed{$var}      ? $config{$renamed{$var}} :
-		 exists $shorewallrc1{$var} ? $shorewallrc1{$var} :
-		 exists $shorewallrc{$var}  ? $shorewallrc{$var} :
 		 exists $actparms{$var}     ? ( $var ? $actparms{$var} : $actparms{0}->{name} ) :
 		 exists $capdesc{$var}      ? have_capability( $var ) : 0 );
 	$val = 0 unless defined $val;
@@ -2554,17 +2557,31 @@ sub expand_variables( \$ ) {
 								  ( length( $var ) == 1 || $var !~ /^0/ ) ) );
 	    fatal_error "Undefined parameter (\$$var)" if ( ! defined $actparms{$var} ) || ( length( $var ) > 1 && $var =~ /^0/ );
 	    $val = $var ? $actparms{$var} : $actparms{0}->{name};
-	} elsif ( exists $params{$var} ) {
+	} elsif ( exists $symbols{$var} ) {
-	    $val = $params{$var};
+	    $val = $symbols{$var};
-	} elsif ( exists $shorewallrc1{$var} ) {
-	    $val = $shorewallrc1{$var}
-	} elsif ( exists $shorewallrc{$var} ) {
-	    $val = $shorewallrc{$var}
 	} elsif ( exists $actparms{$var} ) { 
 	    $val = $actparms{$var};
 	} else {
 	    fatal_error "Undefined shell variable (\$$var)" unless exists $config{$var};
-	    $val = $config{$var};
+	}
+
+	$val = '' unless defined $val;
+	$$lineref = join( '', $first , $val , $rest );
+	fatal_error "Variable Expansion Loop" if ++$count > 100;
+    }
+}
+
+sub expand_shorewallrc_variables( \$ ) {
+    my ( $lineref, $count ) = ( $_[0], 0 );
+    #                         $1      $2   $3                  -     $4
+    while ( $$lineref =~ m( ^(.*?) \$({)? (\d+|[a-zA-Z]\w*) (?(2)}) (.*)$ )x ) {
+
+	my ( $first, $var, $rest ) = ( $1, $3, $4);
+
+	my $val;
+
+	if ( exists $shorewallrc{$var} ) {
+	    $val = $shorewallrc{$var}
 	}
 
 	$val = '' unless defined $val;
@@ -2716,7 +2733,7 @@ sub process_shorewallrc( $$ ) {
 	    if ( $currentline =~ /^([a-zA-Z]\w*)=(.*)$/ ) {
 		my ($var, $val) = ($1, $2);
 		$val = $1 if $val =~ /^\"([^\"]*)\"$/;
-		expand_variables($val) if supplied $val;
+		expand_shorewallrc_variables($val) if supplied $val;
 		$shorewallrc{$var} = $val;
 	    } else {
 		fatal_error "Unrecognized shorewallrc entry";
@@ -4329,18 +4346,38 @@ sub get_params() {
 	    }
 	}
     }
+
+    add_symbols %params;
 }
 
 #
-# Add an entry to %params and to %compiler_params
+# Add an entry to %param, %symbols and to %compiler_params
 #
 sub add_param( $$ ) {
     my ( $param, $value ) = @_;
 
     $params{$param}   = $value;
+    $symbols{$param}  = $value;
     $compiler_params{$param} = 1;
 }
 
+#
+# Add an entry to %symbols
+#
+sub add_symbol( $$ ) {
+    $symbols{$_[0]} = $_[1];
+}
+
+#
+# Add symbols from a hash
+#
+
+sub add_symbols( \% ) {
+    while ( my ( $var, $val ) = each %{$_[0]} ) {
+	$symbols{$var} = $val;
+    }
+}
+
 #
 # emit param=value for each param set in the params file
 #
@@ -4914,8 +4951,13 @@ sub get_configuration( $$$ ) {
     require_capability( 'RECENT_MATCH'    , 'MACLIST_TTL' , 's' )           if $config{MACLIST_TTL};
     require_capability( 'XCONNMARK'       , 'HIGH_ROUTE_MARKS=Yes' , 's' )  if $config{PROVIDER_OFFSET} > 0;
     require_capability( 'MANGLE_ENABLED'  , 'Traffic Shaping' , 's'      )  if $config{TC_ENABLED};
-}
 
+    add_symbols %config;
+
+    while ( my ($var, $val ) = each %renamed ) {
+	$symbols{$var} = $config{$val};
+    }
+}
 #
 # The values of the options in @propagateconfig are copied to the script file in OPTION=<value> format.
 #