[systemd-devel] [PATCH] networkd: Introduce tun/tap device
Susant Sahani
susant at redhat.com
Wed Jun 25 03:43:39 PDT 2014
This patch introduces TUN/TAP device creation support
to networkd.
Example conf to create a tap device:
file: tap.netdev
------------------
[NetDev]
Name=tap-test
Kind=tap
[Tap]
OneQueue=true
MultiQueue=true
PacketInfo=true
------------------
Modifications:
Added:
1. file networkd-tuntap.c
3. netdev kind NETDEV_KIND_TUN and NETDEV_KIND_TAP
2. Tun and Tap Sections and config params to parse
conf and gperf conf parameters
TODO:
1. Add user(uid) group(gid) parameters
---
Makefile.am | 1 +
src/network/networkd-netdev-gperf.gperf | 6 ++
src/network/networkd-netdev.c | 34 ++++++++---
src/network/networkd-tuntap.c | 101 ++++++++++++++++++++++++++++++++
src/network/networkd.h | 9 +++
5 files changed, 144 insertions(+), 7 deletions(-)
create mode 100644 src/network/networkd-tuntap.c
diff --git a/Makefile.am b/Makefile.am
index 4b292b2..165cfc3 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4494,6 +4494,7 @@ libsystemd_networkd_core_la_SOURCES = \
src/network/networkd-tunnel.c \
src/network/networkd-veth.c \
src/network/networkd-vxlan.c \
+ src/network/networkd-tuntap.c \
src/network/networkd-network.c \
src/network/networkd-address.c \
src/network/networkd-route.c \
diff --git a/src/network/networkd-netdev-gperf.gperf b/src/network/networkd-netdev-gperf.gperf
index 9125e1d..38133c8 100644
--- a/src/network/networkd-netdev-gperf.gperf
+++ b/src/network/networkd-netdev-gperf.gperf
@@ -38,3 +38,9 @@ VXLAN.Group, config_parse_tunnel_address, 0,
VXLAN.TOS, config_parse_unsigned, 0, offsetof(NetDev, tos)
VXLAN.TTL, config_parse_unsigned, 0, offsetof(NetDev, ttl)
VXLAN.MacLearning, config_parse_bool, 0, offsetof(NetDev, learning)
+Tun.OneQueue, config_parse_bool, 0, offsetof(NetDev, one_queue)
+Tun.MultiQueue, config_parse_bool, 0, offsetof(NetDev, multi_queue)
+Tun.PacketInfo, config_parse_bool, 0, offsetof(NetDev, packet_info)
+Tap.OneQueue, config_parse_bool, 0, offsetof(NetDev, one_queue)
+Tap.MultiQueue, config_parse_bool, 0, offsetof(NetDev, multi_queue)
+Tap.PacketInfo, config_parse_bool, 0, offsetof(NetDev, packet_info)
diff --git a/src/network/networkd-netdev.c b/src/network/networkd-netdev.c
index dcf7596..644a1d0 100644
--- a/src/network/networkd-netdev.c
+++ b/src/network/networkd-netdev.c
@@ -41,7 +41,9 @@ static const char* const netdev_kind_table[_NETDEV_KIND_MAX] = {
[NETDEV_KIND_GRE] = "gre",
[NETDEV_KIND_SIT] = "sit",
[NETDEV_KIND_VETH] = "veth",
- [NETDEV_KIND_VTI] = "vti"
+ [NETDEV_KIND_VTI] = "vti",
+ [NETDEV_KIND_TUN] = "tun",
+ [NETDEV_KIND_TAP] = "tap"
};
DEFINE_STRING_TABLE_LOOKUP(netdev_kind, NetDevKind);
@@ -221,6 +223,7 @@ static int netdev_enter_ready(NetDev *netdev) {
return 0;
}
+
static int netdev_create_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
NetDev *netdev = userdata;
int r;
@@ -521,11 +524,19 @@ int netdev_set_ifindex(NetDev *netdev, sd_rtnl_message *message) {
return -EINVAL;
}
- if (!streq(kind, received_kind)) {
- log_error_netdev(netdev, "Received newlink with wrong KIND %s, "
- "expected %s", received_kind, kind);
- netdev_enter_failed(netdev);
- return r;
+ switch(netdev->kind) {
+ case NETDEV_KIND_TUN:
+ case NETDEV_KIND_TAP:
+ break;
+ default:
+ if (!streq(kind, received_kind)) {
+ log_error_netdev(netdev,
+ "Received newlink with wrong KIND %s, "
+ "expected %s", received_kind, kind);
+ netdev_enter_failed(netdev);
+ return r;
+ }
+ break;
}
netdev->ifindex = ifindex;
@@ -617,9 +628,10 @@ static int netdev_load_one(Manager *manager, const char *filename) {
netdev->vxlanid = VXLAN_VID_MAX + 1;
netdev->tunnel_pmtudisc = true;
netdev->learning = true;
+ netdev->packet_info = true;
r = config_parse(NULL, filename, file,
- "Match\0NetDev\0VLAN\0MACVLAN\0VXLAN\0Tunnel\0Peer\0",
+ "Match\0NetDev\0VLAN\0MACVLAN\0VXLAN\0Tunnel\0Peer\0Tun\0Tap\0",
config_item_perf_lookup, (void*) network_netdev_gperf_lookup,
false, false, netdev);
if (r < 0) {
@@ -719,6 +731,14 @@ static int netdev_load_one(Manager *manager, const char *filename) {
if (r < 0)
return r;
break;
+
+ case NETDEV_KIND_TUN:
+ case NETDEV_KIND_TAP:
+ r = netdev_create_tuntap(netdev);
+ if (r < 0)
+ return r;
+ break;
+
default:
break;
}
diff --git a/src/network/networkd-tuntap.c b/src/network/networkd-tuntap.c
new file mode 100644
index 0000000..7c1840c
--- /dev/null
+++ b/src/network/networkd-tuntap.c
@@ -0,0 +1,101 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Susant Sahani <susant at redhat.com>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if_tun.h>
+
+#include "networkd.h"
+
+#define TUN_DEV "/dev/net/tun"
+
+
+static int netdev_fill_tuntap_message(NetDev *netdev, struct ifreq *ifr) {
+
+ assert(netdev);
+ assert(ifr);
+
+ memset(ifr, 0, sizeof(*ifr));
+
+ if(netdev->kind != NETDEV_KIND_TAP)
+ ifr->ifr_flags |= IFF_TUN;
+ else
+ ifr->ifr_flags |= IFF_TAP;
+
+ if(!netdev->packet_info)
+ ifr->ifr_flags &= ~IFF_NO_PI;
+ else
+ ifr->ifr_flags |= IFF_NO_PI;
+
+ if(netdev->one_queue)
+ ifr->ifr_flags |= IFF_ONE_QUEUE;
+
+ if(netdev->multi_queue)
+ ifr->ifr_flags |= IFF_MULTI_QUEUE;
+
+ strncpy(ifr->ifr_name, netdev->ifname, IFNAMSIZ-1);
+
+ return 0;
+}
+
+static int netdev_tuntap_add(struct ifreq *ifr) {
+ _cleanup_close_ int fd;
+ int r = 0;
+
+ fd = open(TUN_DEV, O_RDWR);
+ if (fd < 0)
+ return -errno;
+
+ r = ioctl(fd, TUNSETIFF, ifr);
+ if (r < 0)
+ return -errno;
+
+ r = ioctl(fd, TUNSETPERSIST, 1);
+ if (r < 0)
+ return -errno;
+
+ return r;
+}
+
+int netdev_create_tuntap(NetDev *netdev) {
+ struct ifreq ifr;
+ int r;
+
+ assert(netdev);
+ assert(netdev->ifname);
+
+ switch(netdev->kind) {
+ case NETDEV_KIND_TUN:
+ case NETDEV_KIND_TAP:
+ break;
+ default:
+ return -ENOTSUP;
+ }
+
+ r = netdev_fill_tuntap_message(netdev, &ifr);
+ if(r < 0)
+ return r;
+
+ log_debug_netdev(netdev, "Creating tuntap netdev: %s",
+ netdev_kind_to_string(netdev->kind));
+
+ return netdev_tuntap_add(&ifr);
+}
diff --git a/src/network/networkd.h b/src/network/networkd.h
index b7b1d90..7f24635 100644
--- a/src/network/networkd.h
+++ b/src/network/networkd.h
@@ -80,6 +80,8 @@ typedef enum NetDevKind {
NETDEV_KIND_SIT,
NETDEV_KIND_VETH,
NETDEV_KIND_VTI,
+ NETDEV_KIND_TUN,
+ NETDEV_KIND_TAP,
_NETDEV_KIND_MAX,
_NETDEV_KIND_INVALID = -1
} NetDevKind;
@@ -122,6 +124,10 @@ struct NetDev {
bool tunnel_pmtudisc;
bool learning;
+ bool one_queue;
+ bool multi_queue;
+ bool packet_info;
+
unsigned ttl;
unsigned tos;
struct in_addr local;
@@ -342,6 +348,7 @@ int netdev_enslave(NetDev *netdev, Link *link, sd_rtnl_message_handler_t cb);
int netdev_create_tunnel(Link *link, sd_rtnl_message_handler_t callback);
int netdev_create_veth(NetDev *netdev, sd_rtnl_message_handler_t callback);
int netdev_create_vxlan(NetDev *netdev, Link *link, sd_rtnl_message_handler_t callback);
+int netdev_create_tuntap(NetDev *netdev);
const char *netdev_kind_to_string(NetDevKind d) _const_;
NetDevKind netdev_kind_from_string(const char *d) _pure_;
@@ -353,6 +360,8 @@ int config_parse_netdev_kind(const char *unit, const char *filename, unsigned li
int config_parse_macvlan_mode(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_tuntap_kind(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+
/* gperf */
const struct ConfigPerfItem* network_netdev_gperf_lookup(const char *key, unsigned length);
--
1.9.3
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