From 14d8c34e6066bbe0cc132fa95a497cef8c30b14e Mon Sep 17 00:00:00 2001
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Date: Fri, 13 Feb 2015 23:30:29 +0100
Subject: [PATCH] Attempted to simplify the BSD tun handling code

---
 src/tun.c | 60 +++++++++++++++++++++++++++----------------------------
 1 file changed, 30 insertions(+), 30 deletions(-)

diff --git a/src/tun.c b/src/tun.c
index 46b833cd..9e3f900b 100644
--- a/src/tun.c
+++ b/src/tun.c
@@ -322,38 +322,46 @@ static int set_network_info(main_server_st * s, struct proc_st *proc)
 #include <ccan/hash/hash.h>
 
 #ifndef __linux__
-# ifdef SIOCIFCREATE
-static int bsd_open_tun(char *tun_name)
+static int bsd_open_tun(void)
 {
         int fd;
         int s;
+	char tun_name[80];
         struct ifreq ifr;
+	int unit_nr = 0;
 
-        fd = open(tun_name, O_RDWR);
+        fd = open("/dev/tun", O_RDWR);
         if (fd == -1) {
-                s = socket(AF_INET, SOCK_DGRAM, 0);
-                if (s < 0)
-                        return -1;
+        	/* try iterating */
+		for (unit_nr = 0; unit_nr < 255; unit_nr++) {
+			snprintf(tun_name, sizeof(tun_name), "/dev/tun%d", unit_nr);
+			fd = open(tun_name, O_RDWR);
+# ifdef SIOCIFCREATE
+			if (fd == -1) {
+				/* cannot open tunXX, try creating it */
+		                s = socket(AF_INET, SOCK_DGRAM, 0);
+		                if (s < 0)
+		                        return -1;
 
-                memset(&ifr, 0, sizeof(ifr));
-                strncpy(ifr.ifr_name, tun_name + 5, sizeof(ifr.ifr_name) - 1);
-                if (!ioctl(s, SIOCIFCREATE, &ifr))
-                        fd = open(tun_name, O_RDWR);
-
-                close(s);
+		                memset(&ifr, 0, sizeof(ifr));
+		                strncpy(ifr.ifr_name, tun_name + 5, sizeof(ifr.ifr_name) - 1);
+		                if (!ioctl(s, SIOCIFCREATE, &ifr))
+                		        fd = open(tun_name, O_RDWR);
+		                close(s);
+			}
+# endif
+			if (fd >= 0)
+				break;
+		}
         }
+
         return fd;
 }
-# else
-#  define bsd_open_tun(tun_name) open(tun_name, O_RDWR)
-# endif
 #endif
 
 int open_tun(main_server_st * s, struct proc_st *proc)
 {
 	int tunfd, ret, e;
-	static char tun_name[80];
-	int unit_nr = 0;
 	struct ifreq ifr;
 	unsigned int t;
 
@@ -424,20 +432,12 @@ int open_tun(main_server_st * s, struct proc_st *proc)
 	}
 #endif
 #else				/* freebsd */
-	tunfd = bsd_open_tun("/dev/tun");
+	tunfd = bsd_open_tun()
 	if (tunfd < 0) {
-		for (unit_nr = 0; unit_nr < 255; unit_nr++) {
-			sprintf(tun_name, "/dev/tun%d", unit_nr);
-			tunfd = bsd_open_tun(tun_name);
-			if (tunfd >= 0)
-				break;
-		}
-		if (tunfd < 0) {
-			int e = errno;
-			mslog(s, NULL, LOG_ERR, "Can't open /dev/tun: %s\n",
-			      strerror(e));
-			return -1;
-		}
+		int e = errno;
+		mslog(s, NULL, LOG_ERR, "Can't open /dev/tun: %s\n",
+		      strerror(e));
+		return -1;
 	}
 
 	/* find device name */