summaryrefslogtreecommitdiffstats
path: root/src/network/netdev/tuntap.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/network/netdev/tuntap.c161
1 files changed, 161 insertions, 0 deletions
diff --git a/src/network/netdev/tuntap.c b/src/network/netdev/tuntap.c
new file mode 100644
index 0000000..951138d
--- /dev/null
+++ b/src/network/netdev/tuntap.c
@@ -0,0 +1,161 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/if_tun.h>
+#include <net/if.h>
+#include <netinet/if_ether.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "netdev/tuntap.h"
+#include "user-util.h"
+
+#define TUN_DEV "/dev/net/tun"
+
+static int netdev_fill_tuntap_message(NetDev *netdev, struct ifreq *ifr) {
+ TunTap *t;
+
+ assert(netdev);
+ assert(netdev->ifname);
+ assert(ifr);
+
+ if (netdev->kind == NETDEV_KIND_TAP) {
+ t = TAP(netdev);
+ ifr->ifr_flags |= IFF_TAP;
+ } else {
+ t = TUN(netdev);
+ ifr->ifr_flags |= IFF_TUN;
+ }
+
+ if (!t->packet_info)
+ ifr->ifr_flags |= IFF_NO_PI;
+
+ if (t->one_queue)
+ ifr->ifr_flags |= IFF_ONE_QUEUE;
+
+ if (t->multi_queue)
+ ifr->ifr_flags |= IFF_MULTI_QUEUE;
+
+ if (t->vnet_hdr)
+ ifr->ifr_flags |= IFF_VNET_HDR;
+
+ strncpy(ifr->ifr_name, netdev->ifname, IFNAMSIZ-1);
+
+ return 0;
+}
+
+static int netdev_tuntap_add(NetDev *netdev, struct ifreq *ifr) {
+ _cleanup_close_ int fd;
+ TunTap *t = NULL;
+ const char *user;
+ const char *group;
+ uid_t uid;
+ gid_t gid;
+ int r;
+
+ assert(netdev);
+ assert(ifr);
+
+ fd = open(TUN_DEV, O_RDWR|O_CLOEXEC);
+ if (fd < 0)
+ return log_netdev_error_errno(netdev, -errno, "Failed to open tun dev: %m");
+
+ if (ioctl(fd, TUNSETIFF, ifr) < 0)
+ return log_netdev_error_errno(netdev, -errno, "TUNSETIFF failed on tun dev: %m");
+
+ if (netdev->kind == NETDEV_KIND_TAP)
+ t = TAP(netdev);
+ else
+ t = TUN(netdev);
+
+ assert(t);
+
+ if (t->user_name) {
+ user = t->user_name;
+
+ r = get_user_creds(&user, &uid, NULL, NULL, NULL, USER_CREDS_ALLOW_MISSING);
+ if (r < 0)
+ return log_netdev_error_errno(netdev, r, "Cannot resolve user name %s: %m", t->user_name);
+
+ if (ioctl(fd, TUNSETOWNER, uid) < 0)
+ return log_netdev_error_errno(netdev, -errno, "TUNSETOWNER failed on tun dev: %m");
+ }
+
+ if (t->group_name) {
+ group = t->group_name;
+
+ r = get_group_creds(&group, &gid, USER_CREDS_ALLOW_MISSING);
+ if (r < 0)
+ return log_netdev_error_errno(netdev, r, "Cannot resolve group name %s: %m", t->group_name);
+
+ if (ioctl(fd, TUNSETGROUP, gid) < 0)
+ return log_netdev_error_errno(netdev, -errno, "TUNSETGROUP failed on tun dev: %m");
+
+ }
+
+ if (ioctl(fd, TUNSETPERSIST, 1) < 0)
+ return log_netdev_error_errno(netdev, -errno, "TUNSETPERSIST failed on tun dev: %m");
+
+ return 0;
+}
+
+static int netdev_create_tuntap(NetDev *netdev) {
+ struct ifreq ifr = {};
+ int r;
+
+ r = netdev_fill_tuntap_message(netdev, &ifr);
+ if (r < 0)
+ return r;
+
+ return netdev_tuntap_add(netdev, &ifr);
+}
+
+static void tuntap_done(NetDev *netdev) {
+ TunTap *t = NULL;
+
+ assert(netdev);
+
+ if (netdev->kind == NETDEV_KIND_TUN)
+ t = TUN(netdev);
+ else
+ t = TAP(netdev);
+
+ assert(t);
+
+ t->user_name = mfree(t->user_name);
+ t->group_name = mfree(t->group_name);
+}
+
+static int tuntap_verify(NetDev *netdev, const char *filename) {
+ assert(netdev);
+
+ if (netdev->mtu != 0)
+ log_netdev_warning(netdev, "MTU configured for %s, ignoring", netdev_kind_to_string(netdev->kind));
+
+ if (netdev->mac)
+ log_netdev_warning(netdev, "MAC configured for %s, ignoring", netdev_kind_to_string(netdev->kind));
+
+ return 0;
+}
+
+const NetDevVTable tun_vtable = {
+ .object_size = sizeof(TunTap),
+ .sections = "Match\0NetDev\0Tun\0",
+ .config_verify = tuntap_verify,
+ .done = tuntap_done,
+ .create = netdev_create_tuntap,
+ .create_type = NETDEV_CREATE_INDEPENDENT,
+};
+
+const NetDevVTable tap_vtable = {
+ .object_size = sizeof(TunTap),
+ .sections = "Match\0NetDev\0Tap\0",
+ .config_verify = tuntap_verify,
+ .done = tuntap_done,
+ .create = netdev_create_tuntap,
+ .create_type = NETDEV_CREATE_INDEPENDENT,
+};