1 files changed, 115 insertions, 0 deletions
diff --git a/cbits/tun-macos.c b/cbits/tun-macos.c
new file mode 100644
index 0000000..7d57350
--- /dev/null
+++ b/cbits/tun-macos.c
@@ -0,0 +1,115 @@
+/**
+  Copyright (C) 2015 clowwindy
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+// Extracted from ShadowVPN project, with some minor modifications.
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include <net/if_utun.h>
+#include <netinet/ip.h>
+#include <sys/ioctl.h>
+#include <sys/kern_control.h>
+#include <sys/sys_domain.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+#include "tun.h"
+
+int tun_alloc(const char *dev_name, int threads, int *fds) {
+    struct ctl_info ctlInfo;
+    struct sockaddr_ctl sc;
+    int fd, utun_num;
+
+    if (!dev_name || sscanf(dev_name, "utun%d", &utun_num) != 1)
+        return -1;
+
+    memset(&ctlInfo, 0, sizeof(ctlInfo));
+
+    if (strlcpy(ctlInfo.ctl_name,
+                UTUN_CONTROL_NAME,
+                sizeof(ctlInfo.ctl_name)) >= sizeof(ctlInfo.ctl_name)) {
+        return -1;
+    }
+
+    fd = socket(PF_SYSTEM, SOCK_DGRAM, SYSPROTO_CONTROL);
+
+    if (fd < 0)
+        return -1;
+
+    if (ioctl(fd, CTLIOCGINFO, &ctlInfo) < 0) {
+        close(fd);
+        return -1;
+    }
+
+    sc.sc_id = ctlInfo.ctl_id;
+    sc.sc_len = sizeof(sc);
+    sc.sc_family = AF_SYSTEM;
+    sc.ss_sysaddr = AF_SYS_CONTROL;
+
+    sc.sc_unit = utun_num + 1;
+
+    if (connect(fd, (struct sockaddr*)&sc, sizeof(sc)) < 0) {
+        close(fd);
+        return -1;
+    }
+
+    *fds = fd;
+
+    return 1;
+}
+
+inline int utun_modified_len(int len) {
+    if (len > 0)
+        return (len > sizeof(u_int32_t)) ? len - sizeof(u_int32_t) : 0;
+    else
+        return len;
+}
+
+int utun_read(int fd, void *buf, size_t len) {
+    u_int32_t type;
+    struct iovec iv[2];
+
+    iv[0].iov_base = &type;
+    iv[0].iov_len = sizeof(type);
+    iv[1].iov_base = buf;
+    iv[1].iov_len = len;
+
+    return utun_modified_len(readv(fd, iv, 2));
+}
+
+int utun_write(int fd, void *buf, size_t len) {
+    u_int32_t type;
+    struct iovec iv[2];
+    struct ip *iph;
+
+    iph = (struct ip *) buf;
+
+    if (iph->ip_v == 6)
+        type = htonl(AF_INET6);
+    else
+        type = htonl(AF_INET);
+
+    iv[0].iov_base = &type;
+    iv[0].iov_len = sizeof(type);
+    iv[1].iov_base = buf;
+    iv[1].iov_len = len;
+
+    return utun_modified_len(writev(fd, iv, 2));
+}
+