Fork open file descriptors

* Add O_CLOEXEC to all open(...) calls
  * Add "e" to all fopen(...) calls
  * Prevents passing open file descriptors to child
    processes.  Leaving psid's available to the child
    could cause unwanted i/o problems and possibly a
    security leak.

configure.ac

@@ -123,6 +123,8 @@ AC_FUNC_STRFTIME
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([getaddrinfo gethostbyname hstrerror gmtime_r localtime_r memmove memset mkdir select setenv snprintf socket socketpair strcasecmp strcasestr strchr strdup strerror strlcpy strncasecmp strrchr strstr strtol uname unsetenv vsnprintf])
 
+# Check for O_CLOEXEC
+AC_FCNTL_FLAGS
 
 AC_PRESERVE_HELP_ORDER
 

m4/funcs.m4

@@ -13,3 +13,25 @@ AC_DEFINE_UNQUOTED([HAVE_]FUNC_NAME_UC, $ac_cv_have_func_[]$1, [Define to 1 if w
 LIBS="$LIBS_search_libs_save"
 
 ])
+
+# ---------------------------------------------------------------------------
+# Macro: FCNTL_FLAGS
+# ---------------------------------------------------------------------------
+
+AC_DEFUN([AC_FCNTL_FLAGS],
+[
+  AC_CACHE_CHECK([for O_CLOEXEC], [ac_cv_o_cloexec], [
+    AC_LANG_PUSH([C])
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$CFLAGS -I${srcdir}"
+
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <fcntl.h>], [ int flags= O_CLOEXEC])], [ac_cv_o_cloexec="yes"], [ac_cv_o_cloexec="no"])
+    AC_LANG_POP
+  ])
+
+  AS_IF([test "x$ac_cv_o_cloexec" = "xyes"],[ AC_DEFINE(HAVE_O_CLOEXEC, 1, [Define to 1 if you have O_CLOEXEC defined])])
+])
+
+# ---------------------------------------------------------------------------
+# End Macro: FCNTL_FLAGS
+# ---------------------------------------------------------------------------

src/misc/configuration.cxx

@@ -886,7 +886,7 @@ static bool open_serial(const char* dev)
 {
 	bool ret = false;
 #ifdef __CYGWIN__
-	int fd = open(dev, O_RDWR | O_NOCTTY | O_NDELAY);
+	int fd = open(dev, O_RDWR | O_NOCTTY | O_NDELAY | O_CLOEXEC);
 	if (fd != -1) {
 		close(fd);
 		ret = true;

src/rigcontrol/ptt.cxx

@@ -204,7 +204,12 @@ void PTT::open_tty(void)
 	com_to_tty(pttdevName);
 #    endif
 
-	if ((pttfd = open(pttdevName.c_str(), O_RDWR | O_NOCTTY | O_NDELAY)) < 0) {
+	int oflags = O_RDWR | O_NOCTTY | O_NDELAY;
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+	if ((pttfd = open(pttdevName.c_str(), oflags)) < 0) {
 		LOG_ERROR("Could not open \"%s\": %s", pttdevName.c_str(), strerror(errno));
 		return;
 	}
@@ -295,8 +300,13 @@ void PTT::set_tty(bool ptt)
 void PTT::open_parport(void)
 {
     if (progdefaults.PTTdev.find("tty") != string::npos) return;
-    
-	if ((pttfd = open(progdefaults.PTTdev.c_str(), O_RDWR | O_NDELAY)) == -1) {
+
+	int oflags = O_RDWR | O_NDELAY;
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+	if ((pttfd = open(progdefaults.PTTdev.c_str(),  oflags)) == -1) {
 		LOG_ERROR("Could not open %s: %s", progdefaults.PTTdev.c_str(), strerror(errno));
 		return;
 	}
@@ -417,7 +427,13 @@ static bool open_fifos(const char* base, int fd[2])
 		LOG_ERROR("%s is not a fifo", fifo.c_str());
 		return false;
 	}
-	if ((fd[0] = open(fifo.c_str(), O_RDONLY | O_NONBLOCK)) == -1) {
+
+	int oflags = O_RDONLY | O_NONBLOCK;
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+	if ((fd[0] = open(fifo.c_str(), oflags)) == -1) {
 		LOG_ERROR("Could not open %s: %s", fifo.c_str(), strerror(errno));
 		return false;
 	}
@@ -428,7 +444,13 @@ static bool open_fifos(const char* base, int fd[2])
 		LOG_ERROR("%s is not a fifo", fifo.c_str());
 		return false;
 	}
-	if ((fd[1] = open(fifo.c_str(), O_WRONLY | O_NONBLOCK)) == -1) {
+	oflags = O_WRONLY | O_NONBLOCK;
+
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+	if ((fd[1] = open(fifo.c_str(), oflags)) == -1) {
 		LOG_ERROR("Could not open %s: %s", fifo.c_str(), strerror(errno));
 		return false;
 	}

src/rigcontrol/rigMEM.cxx

@@ -301,7 +301,7 @@ static void *rigMEM_loop(void *args)
 			break;
 
 		if (TogglePTT || rig_qsy || change_mode) {
-			IOout = fopen("c:/RIGCTL/ptt", "w");
+			IOout = fopen("c:/RIGCTL/ptt", "we");
 			if (IOout) {
 				LOG_VERBOSE("sent %d, %c, %s",
 					 (int)qsy_f,
@@ -318,7 +318,7 @@ static void *rigMEM_loop(void *args)
 			}
 		}
 
-		IOin = fopen("c:/RIGCTL/rig", "r");
+		IOin = fopen("c:/RIGCTL/rig", "re");
 		if (IOin) {
 			fscanf(IOin, "%ld\n", &IOfreq);
 			fscanf(IOin, "%s", szmode);

src/rigcontrol/serial.cxx

@@ -71,7 +71,13 @@ bool Cserial::OpenPort()  {
 #ifdef __CYGWIN__
 	com_to_tty(device);
 #endif
-	if ((fd = open( device.c_str(), O_RDWR | O_NOCTTY | O_NDELAY)) < 0)
+
+	int oflags = O_RDWR | O_NOCTTY | O_NDELAY;
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+	if ((fd = open( device.c_str(), oflags)) < 0)
 		return false;
 // save current port settings
 	tcflush (fd, TCIFLUSH);

src/soundcard/mixer.cxx

@@ -73,7 +73,13 @@ void MixerOSS::openMixer(const char *dev)
 	if (mixer_fd != -1) closeMixer();
 	mixer = dev;
 	try {
-		mixer_fd =  open(mixer.c_str(), O_RDWR);
+
+	int oflags = O_RDWR;
+#	ifdef HAVE_O_CLOEXEC
+		oflags = oflags | O_CLOEXEC;
+#	endif
+
+		mixer_fd =  open(mixer.c_str(), oflags);
 		if (mixer_fd == -1)
 			throw MixerException(errno);
 		if ((err = initMask()) != 0)
@@ -144,7 +150,12 @@ void MixerOSS::findNumMixers()
 			szDevice[10] = 0;
 		else
 			szDevice[10] = '0'+(i-1);
-		fd = open(szDevice, O_RDWR);
+		int oflags = O_RDWR;
+#		ifdef HAVE_O_CLOEXEC
+			oflags = oflags | O_CLOEXEC;
+#		endif
+
+		fd = open(szDevice, oflags);
 		if (fd >= 0) {
 			Devices[NumMixers] = i;
 			NumMixers++;

src/soundcard/sound.cxx

@@ -399,7 +399,12 @@ int SoundOSS::Open(int md, int freq)
 
 	mode = md;
 	try {
-		device_fd = open(device.c_str(), mode, 0);
+		int oflags = md;
+#		ifdef HAVE_O_CLOEXEC
+			oflags = oflags | O_CLOEXEC;
+#		endif
+
+		device_fd = open(device.c_str(), oflags, 0);
 		if (device_fd == -1)
 			throw SndException(errno);
 		Format(AFMT_S16_LE);	// default: 16 bit little endian