--- a/Makefile
+++ b/Makefile
@@ -2,11 +2,26 @@
 # (c) 2004-2009 Daniel Stoedle, daniels@cs.uit.no
 # ptunnel.exe target added by Mike Miller, mike@mikeage.net
 
-CC	 		= gcc
-CFLAGS		= -Wall -g
-LDOPTS		= -lpthread -lpcap
+# set to 1 to enable debug symbols
+DEBUG=0
+
+# set to 1 to enable selinux support
+SELINUX=0
+
+CC         ?= gcc
+CFLAGS		+= -Wall
+LIBS		+= -lpthread -lpcap
 PT_OBJS		= ptunnel.o md5.o
 
+ifeq ($(DEBUG),1)
+CFLAGS += -g
+endif
+
+ifeq ($(SELINUX),1)
+CPPFLAGS += -DHAVE_SELINUX
+LIBS += -lselinux
+endif
+
 WIN32_CC    = mingw32-gcc
 WIN32_CFLAGS = -g -Wall -DWIN32 -I"c:\Program Files\WpdPack\Include"
 WIN32_LDOPTS = -lwpcap -lwsock32 -L"c:\Program Files\WpdPack\Lib"
@@ -26,13 +41,13 @@
 	
 
 install: ptunnel
-	install -d $(bindir)/
-	install -d $(mandir)/
-	install ./ptunnel $(bindir)/ptunnel
-	install ./ptunnel.8 $(mandir)/ptunnel.8
+	install -d "$(DESTDIR)/$(bindir)/"
+	install -d "$(DESTDIR)/$(mandir)/"
+	install -m755 ./ptunnel "$(DESTDIR)/$(bindir)/ptunnel"
+	install -m644 ./ptunnel.8 "$(DESTDIR)/$(mandir)/ptunnel.8"
 
 ptunnel: $(PT_OBJS)
-	$(CC) -o $@ $^ $(LDOPTS) `[ -e /usr/include/selinux/selinux.h ] && echo -lselinux`
+	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS) $(LIBS)
 
 ptunnel.exe: $(WIN32_PT_OBJS)
 	$(CC) -o $@ $^ $(WIN32_LDOPTS)
@@ -47,7 +62,7 @@
 	$(CC) $(CFLAGS) -MM *.c > $@
 
 %.o:%.c
-	$(CC) $(CFLAGS) `[ -e /usr/include/selinux/selinux.h ] && echo -DHAVE_SELINUX` -c -o $@ $<
+	$(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
 
 %.obj:%.c
 	$(WIN32_CC) $(WIN32_CFLAGS) -c -o $@ $<