Initial commit

1 files changed, 40 insertions, 0 deletions

diff --git a/cbits/tun-linux.c b/cbits/tun-linux.c
new file mode 100644
index 0000000..adbd7c2
--- /dev/null
+++ b/cbits/tun-linux.c
@@ -0,0 +1,40 @@
+#include <string.h>
+
+#include <fcntl.h>
+#include <linux/if_tun.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include "tun.h"
+
+int tun_alloc(const char *dev_name, int threads, int *fds) {
+    struct ifreq ifr;
+    int fd, i;
+
+    if (!dev_name)
+        return -1;
+
+    memset(&ifr, 0, sizeof(ifr));
+
+    ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+    if (threads > 1)
+        ifr.ifr_flags |= IFF_MULTI_QUEUE;
+    strncpy(ifr.ifr_name, dev_name, IFNAMSIZ);
+
+    for (i = 0; i < threads; i++) {
+        if ((fd = open("/dev/net/tun", O_RDWR)) < 0)
+            goto err;
+        if (ioctl(fd, TUNSETIFF, (void *)&ifr) != 0) {
+            close(fd);
+            goto err;
+        }
+        fds[i] = fd;
+    }
+
+    return threads;
+err:
+    for (--i; i >= 0; i--)
+        close(fds[i]);
+    return -1;
+}