From: Antonio Quartulli <a...@unstable.cc>
This function is similar to the essence of open_tun_generic(), but
calling open_tun_dco() instead of trying to do a file open on
"/dev/%s"
Previous attempts to save code duplication by including this into
open_tun_generic() created additional #ifdef plus confusing call
paths. So this is a clean new function, leaving the door open for
a cleanup of open_tun_generic().
Also, introduce tun_dco_enabled(tt) to avoid the negative
"!tt->options.disable_dco" calls.
Signed-off-by: Antonio Quartulli <a...@unstable.cc>
Signed-off-by: Gert Doering <g...@greenie.muc.de>
--
v11:
- add new function open_tun_dco_generic() for Linux (and FreeBSD, later)
instead of lumping this into open_tun_generic()
- pick up tun_dco_enabled() from a later patch in the series
(easier to bring this in right now than to convert the code back
and then patch it again later)
---
src/openvpn/init.c | 24 +++++++-
src/openvpn/init.h | 2 +-
src/openvpn/options.c | 7 +++
src/openvpn/tun.c | 129 +++++++++++++++++++++++++++++++++++++-----
src/openvpn/tun.h | 2 +-
5 files changed, 147 insertions(+), 17 deletions(-)
diff --git a/src/openvpn/init.c b/src/openvpn/init.c
index 1bfbf4eb..779fc4a5 100644
--- a/src/openvpn/init.c
+++ b/src/openvpn/init.c
@@ -1054,7 +1054,7 @@ do_genkey(const struct options *options)
* Persistent TUN/TAP device management mode?
*/
bool
-do_persist_tuntap(const struct options *options, openvpn_net_ctx_t *ctx)
+do_persist_tuntap(struct options *options, openvpn_net_ctx_t *ctx)
{
if (options->persist_config)
{
@@ -1069,6 +1069,26 @@ do_persist_tuntap(const struct options *options,
openvpn_net_ctx_t *ctx)
msg(M_FATAL|M_OPTERR,
"options --mktun or --rmtun should only be used together with
--dev");
}
+
+#if defined(ENABLE_DCO)
+ if (dco_enabled(options))
+ {
+ /* creating a DCO interface via --mktun is not supported as it
does not
+ * make much sense. Since DCO is enabled by default, people may
run into
+ * this without knowing, therefore this case should be properly
handled.
+ *
+ * Disable DCO if --mktun was provided and print a message to let
+ * user know.
+ */
+ if (dev_type_enum(options->dev, options->dev_type) == DEV_TYPE_TUN)
+ {
+ msg(M_WARN, "Note: --mktun does not support DCO. Creating TUN
interface.");
+ }
+
+ options->tuntap_options.disable_dco = true;
+ }
+#endif
+
#ifdef ENABLE_FEATURE_TUN_PERSIST
tuncfg(options->dev, options->dev_type, options->dev_node,
options->persist_mode,
@@ -1763,7 +1783,7 @@ do_open_tun(struct context *c)
#endif
/* open the tun device */
open_tun(c->options.dev, c->options.dev_type, c->options.dev_node,
- c->c1.tuntap);
+ c->c1.tuntap, &c->net_ctx);
/* set the hardware address */
if (c->options.lladdr)
diff --git a/src/openvpn/init.h b/src/openvpn/init.h
index 2b8c2dcc..5f412a33 100644
--- a/src/openvpn/init.h
+++ b/src/openvpn/init.h
@@ -56,7 +56,7 @@ bool print_openssl_info(const struct options *options);
bool do_genkey(const struct options *options);
-bool do_persist_tuntap(const struct options *options, openvpn_net_ctx_t *ctx);
+bool do_persist_tuntap(struct options *options, openvpn_net_ctx_t *ctx);
bool possibly_become_daemon(const struct options *options);
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index b00acf7e..87d6fc31 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -3667,6 +3667,13 @@ options_postprocess_mutate(struct options *o, struct
env_set *es)
o->tuntap_options.disable_dco = !dco_check_option_conflict(D_DCO, o);
#endif
+ if (dco_enabled(o) && o->dev_node)
+ {
+ msg(M_WARN, "Note: ignoring --dev-node as it has no effect when using "
+ "data channel offload");
+ o->dev_node = NULL;
+ }
+
/*
* Save certain parms before modifying options during connect, especially
* when using --pull
diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 3f9aa6ae..30abfdd1 100644
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -37,6 +37,7 @@
#include "syshead.h"
+#include "openvpn.h"
#include "tun.h"
#include "fdmisc.h"
#include "common.h"
@@ -1723,6 +1724,15 @@ tun_name_is_fixed(const char *dev)
return has_digit(dev);
}
+#if defined(TARGET_LINUX)
+static bool
+tun_dco_enabled(struct tuntap *tt)
+{
+ return !tt->options.disable_dco;
+}
+#endif
+
+
#if !(defined(_WIN32) || defined(TARGET_LINUX))
static void
open_tun_generic(const char *dev, const char *dev_type, const char *dev_node,
@@ -1831,6 +1841,76 @@ open_tun_generic(const char *dev, const char *dev_type,
const char *dev_node,
}
#endif /* !_WIN32 && !TARGET_LINUX */
+#if defined(TARGET_LINUX)
+static void
+open_tun_dco_generic(const char *dev, const char *dev_type,
+ struct tuntap *tt, openvpn_net_ctx_t *ctx)
+{
+ char dynamic_name[256];
+ bool dynamic_opened = false;
+
+ if (tt->type == DEV_TYPE_NULL)
+ {
+ open_null(tt);
+ return;
+ }
+
+ /*
+ * dynamic open is indicated by --dev specified without
+ * explicit unit number. Try opening /dev/[dev]n
+ * where n = [0, 255].
+ */
+
+ if (!tun_name_is_fixed(dev))
+ {
+ for (int i = 0; i < 256; ++i)
+ {
+ openvpn_snprintf(dynamic_name, sizeof(dynamic_name),
+ "%s%d", dev, i);
+ if (open_tun_dco(tt, ctx, dynamic_name) == 0)
+ {
+ dynamic_opened = true;
+ msg(M_INFO, "DCO device %s opened", dynamic_name);
+ break;
+ }
+ msg(D_READ_WRITE | M_ERRNO, "Tried opening %s (failed)",
dynamic_name);
+ }
+ if (!dynamic_opened)
+ {
+ msg(M_FATAL, "Cannot allocate DCO dev dynamically");
+ }
+ /* tt->actual_name is passed to up and down scripts and used as
+ * the ifconfig dev name */
+ tt->actual_name = string_alloc(dynamic_name, NULL);
+ }
+ /*
+ * explicit unit number specified
+ */
+ else
+ {
+ int ret = open_tun_dco(tt, ctx, dev);
+ if (ret == -EEXIST)
+ {
+ msg(M_INFO, "DCO device %s already exists, won't be destroyed at
shutdown",
+ dev);
+ tt->persistent_if = true;
+ }
+ else if (ret < 0)
+ {
+ msg(M_ERR, "Cannot open DCO device %s: %s (%d)", dev,
+ strerror(-ret), ret);
+ }
+ else
+ {
+ msg(M_INFO, "DCO device %s opened", dev);
+ }
+
+ /* tt->actual_name is passed to up and down scripts and used as the
ifconfig dev name */
+ tt->actual_name = string_alloc(dev, NULL);
+ }
+}
+#endif /* TARGET_LINUX */
+
#if !defined(_WIN32)
static void
close_tun_generic(struct tuntap *tt)
@@ -1847,7 +1927,8 @@ close_tun_generic(struct tuntap *tt)
#if defined (TARGET_ANDROID)
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
#define ANDROID_TUNNAME "vpnservice-tun"
struct user_pass up;
@@ -1944,7 +2025,8 @@ read_tun(struct tuntap *tt, uint8_t *buf, int len)
#if !PEDANTIC
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
struct ifreq ifr;
@@ -1955,6 +2037,10 @@ open_tun(const char *dev, const char *dev_type, const
char *dev_node, struct tun
{
open_null(tt);
}
+ else if (tun_dco_enabled(tt))
+ {
+ open_tun_dco_generic(dev, dev_type, tt, ctx);
+ }
else
{
/*
@@ -2061,7 +2147,8 @@ open_tun(const char *dev, const char *dev_type, const
char *dev_node, struct tun
#else /* if !PEDANTIC */
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
ASSERT(0);
}
@@ -2086,7 +2173,8 @@ tuncfg(const char *dev, const char *dev_type, const char
*dev_node,
clear_tuntap(tt);
tt->type = dev_type_enum(dev, dev_type);
tt->options = *options;
- open_tun(dev, dev_type, dev_node, tt);
+
+ open_tun(dev, dev_type, dev_node, tt, ctx);
if (ioctl(tt->fd, TUNSETPERSIST, persist_mode) < 0)
{
msg(M_ERR, "Cannot ioctl TUNSETPERSIST(%d) %s", persist_mode, dev);
@@ -2204,6 +2292,12 @@ close_tun(struct tuntap *tt, openvpn_net_ctx_t *ctx)
net_ctx_reset(ctx);
}
+#ifdef TARGET_LINUX
+ if (tun_dco_enabled(tt))
+ {
+ close_tun_dco(tt, ctx);
+ }
+#endif
close_tun_generic(tt);
free(tt);
}
@@ -2227,7 +2321,8 @@ read_tun(struct tuntap *tt, uint8_t *buf, int len)
#endif
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
int if_fd, ip_muxid, arp_muxid, arp_fd, ppa = -1;
struct lifreq ifr;
@@ -2579,7 +2674,8 @@ read_tun(struct tuntap *tt, uint8_t *buf, int len)
#elif defined(TARGET_OPENBSD)
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
open_tun_generic(dev, dev_type, dev_node, true, tt);
@@ -2673,7 +2769,8 @@ read_tun(struct tuntap *tt, uint8_t *buf, int len)
*/
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
open_tun_generic(dev, dev_type, dev_node, true, tt);
@@ -2813,7 +2910,8 @@ freebsd_modify_read_write_return(int len)
}
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
open_tun_generic(dev, dev_type, dev_node, true, tt);
@@ -2941,7 +3039,8 @@ dragonfly_modify_read_write_return(int len)
}
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
open_tun_generic(dev, dev_type, dev_node, true, tt);
@@ -3169,7 +3268,8 @@ open_darwin_utun(const char *dev, const char *dev_type,
const char *dev_node, st
#endif /* ifdef HAVE_NET_IF_UTUN_H */
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
#ifdef HAVE_NET_IF_UTUN_H
/* If dev_node does not start start with utun assume regular tun/tap */
@@ -3276,7 +3376,8 @@ read_tun(struct tuntap *tt, uint8_t *buf, int len)
#elif defined(TARGET_AIX)
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
char tunname[256];
char dynamic_name[20];
@@ -6585,7 +6686,8 @@ tuntap_post_open(struct tuntap *tt, const char
*device_guid)
}
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
const char *device_guid = NULL;
@@ -6894,7 +6996,8 @@ ipset2ascii_all(struct gc_arena *gc)
#else /* generic */
void
-open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt)
+open_tun(const char *dev, const char *dev_type, const char *dev_node, struct
tuntap *tt,
+ openvpn_net_ctx_t *ctx)
{
open_tun_generic(dev, dev_type, dev_node, true, tt);
}
diff --git a/src/openvpn/tun.h b/src/openvpn/tun.h
index b7786f46..8ec8f51f 100644
--- a/src/openvpn/tun.h
+++ b/src/openvpn/tun.h
@@ -249,7 +249,7 @@ tuntap_ring_empty(struct tuntap *tt)
*/
void open_tun(const char *dev, const char *dev_type, const char *dev_node,
- struct tuntap *tt);
+ struct tuntap *tt, openvpn_net_ctx_t *ctx);
void close_tun(struct tuntap *tt, openvpn_net_ctx_t *ctx);
--
2.25.1
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