From: Nikos Mavrogiannopoulos <nmav@redhat.com>
Date: Wed, 22 Oct 2014 10:19:25 +0000 (+0200)
Subject: added gnutls_fd_in_use() to check whether a file descriptor is in use
X-Git-Tag: gnutls_3_4_0~764
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2c12530bacc89485e807ec18ae455f4e190b383f;p=thirdparty%2Fgnutls.git

added gnutls_fd_in_use() to check whether a file descriptor is in use
---

diff --git a/lib/gnutls_state.c b/lib/gnutls_state.c
index 40be26e847..4f06ea4b5b 100644
--- a/lib/gnutls_state.c
+++ b/lib/gnutls_state.c
@@ -1162,6 +1162,28 @@ int gnutls_session_is_resumed(gnutls_session_t session)
 	return 0;
 }
 
+/**
+ * gnutls_fd_in_use:
+ * @fd: is a file descriptor to check against
+ *
+ * Check whether the provided file descriptor is used by
+ * gnutls internally. That is whether is used for /dev/urandom
+ * etc. That function is to be used by applications that close()
+ * all file descriptors on application startup.
+ *
+ * Returns: non zero if this fd is in use, or a zero otherwise.
+ **/
+unsigned gnutls_fd_in_use(int fd)
+{
+#ifdef _WIN32
+	return 0;
+#else
+	if (fd >= 0 && fd == _gnutls_urandom_fd)
+		return 1;
+	return 0;
+#endif
+}
+
 /**
  * gnutls_session_resumption_requested:
  * @session: is a #gnutls_session_t structure.
diff --git a/lib/includes/gnutls/gnutls.h.in b/lib/includes/gnutls/gnutls.h.in
index 7ddc5738ac..158aaed10c 100644
--- a/lib/includes/gnutls/gnutls.h.in
+++ b/lib/includes/gnutls/gnutls.h.in
@@ -2163,6 +2163,9 @@ void gnutls_certificate_set_pin_function(gnutls_certificate_credentials_t,
 					 gnutls_pin_callback_t fn,
 					 void *userdata);
 
+/* FD-related functions */
+unsigned gnutls_fd_in_use(int fd);
+
 /* FIPS140-2 related functions */
 int gnutls_fips140_mode_enabled(void);
 
diff --git a/lib/nettle/rnd-common.c b/lib/nettle/rnd-common.c
index 1ea52ad80f..26d4c31440 100644
--- a/lib/nettle/rnd-common.c
+++ b/lib/nettle/rnd-common.c
@@ -126,7 +126,7 @@ void _rnd_system_entropy_deinit(void)
 #include <locks.h>
 #include "egd.h"
 
-static int device_fd = -1;
+int _gnutls_urandom_fd = -1;
 
 static int _rnd_get_system_entropy_urandom(void* _rnd, size_t size)
 {
@@ -136,7 +136,7 @@ static int _rnd_get_system_entropy_urandom(void* _rnd, size_t size)
 	for (done = 0; done < size;) {
 		int res;
 		do {
-			res = read(device_fd, rnd + done, size - done);
+			res = read(_gnutls_urandom_fd, rnd + done, size - done);
 		} while (res < 0 && errno == EINTR);
 
 		if (res <= 0) {
@@ -167,7 +167,7 @@ int _rnd_get_system_entropy_egd(void* _rnd, size_t size)
 
 	for (done = 0; done < size;) {
 		res =
-		    _rndegd_read(&device_fd, rnd + done, size - done);
+		    _rndegd_read(&_gnutls_urandom_fd, rnd + done, size - done);
 		if (res <= 0) {
 			if (res < 0) {
 				_gnutls_debug_log("Failed to read egd.\n");
@@ -189,22 +189,22 @@ int _rnd_system_entropy_init(void)
 {
 int old;
 
-	device_fd = open("/dev/urandom", O_RDONLY);
-	if (device_fd < 0) {
+	_gnutls_urandom_fd = open("/dev/urandom", O_RDONLY);
+	if (_gnutls_urandom_fd < 0) {
 		_gnutls_debug_log("Cannot open urandom!\n");
 		goto fallback;
 	}
 
-	old = fcntl(device_fd, F_GETFD);
+	old = fcntl(_gnutls_urandom_fd, F_GETFD);
 	if (old != -1)
-		fcntl(device_fd, F_SETFD, old | FD_CLOEXEC);
+		fcntl(_gnutls_urandom_fd, F_SETFD, old | FD_CLOEXEC);
 
 	_rnd_get_system_entropy = _rnd_get_system_entropy_urandom;
 
 	return 0;
 fallback:
-	device_fd = _rndegd_connect_socket();
-	if (device_fd < 0) {
+	_gnutls_urandom_fd = _rndegd_connect_socket();
+	if (_gnutls_urandom_fd < 0) {
 		_gnutls_debug_log("Cannot open egd socket!\n");
 		return
 			gnutls_assert_val
@@ -217,9 +217,9 @@ fallback:
 
 void _rnd_system_entropy_deinit(void)
 {
-	if (device_fd >= 0) {
-		close(device_fd);
-		device_fd = -1;
+	if (_gnutls_urandom_fd >= 0) {
+		close(_gnutls_urandom_fd);
+		_gnutls_urandom_fd = -1;
 	}
 }
 #endif
diff --git a/lib/random.h b/lib/random.h
index 0aa154527b..8c755f8997 100644
--- a/lib/random.h
+++ b/lib/random.h
@@ -48,4 +48,8 @@ inline static void _gnutls_rnd_refresh(void)
 void _gnutls_rnd_deinit(void);
 int _gnutls_rnd_init(void);
 
+#ifndef _WIN32
+extern int _gnutls_urandom_fd;
+#endif
+
 #endif