| Message ID | 20181016102627.18676-5-simon@rozman.si |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [Openvpn-devel,1/5] Set output name to libopenvpnmsica.dll in MSVC builds too | expand |
Samuli, LGTM.
-----Original Message-----
From: Simon Rozman <simon@rozman.si>
Sent: Tuesday, October 16, 2018 3:26 AM
To: openvpn-devel@lists.sourceforge.net
Subject: [Openvpn-devel] [PATCH 5/5] Detect TAP interfaces with root-enumerated hardware ID
This patch extends the TAP interface enumerating to detect the TAP
interfaces registered using "root\tap0901" hardware ID. Before, only TAP
interfaces with legacy "tap0901" HWID were detected by openvpn.exe.
The openvpnmsica.dll and tapctl.exe install TAP interfaces using root-
enumerated HWIDs, and were not detected by openvpn.exe.
---
src/openvpn/tun.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c
index 948fd17d..5fde2ab8 100644
--- a/src/openvpn/tun.c
+++ b/src/openvpn/tun.c
@@ -3524,7 +3524,8 @@ get_tap_reg(struct gc_arena *gc)
if (status == ERROR_SUCCESS && data_type == REG_SZ)
{
- if (!strcmp(component_id, TAP_WIN_COMPONENT_ID))
+ if (!strcmp(component_id, TAP_WIN_COMPONENT_ID) ||
+ !strcmp(component_id, "root\\" TAP_WIN_COMPONENT_ID))
{
struct tap_reg *reg;
ALLOC_OBJ_CLEAR_GC(reg, struct tap_reg, gc);
Hi, On Tue, Oct 16, 2018 at 12:26:27PM +0200, Simon Rozman wrote: > This patch extends the TAP interface enumerating to detect the TAP > interfaces registered using "root\tap0901" hardware ID. Before, only TAP > interfaces with legacy "tap0901" HWID were detected by openvpn.exe. > > The openvpnmsica.dll and tapctl.exe install TAP interfaces using root- > enumerated HWIDs, and were not detected by openvpn.exe. I do not see a specific reason to *not* apply this patch, but I'm wondering if you could shed some background light on the changed behaviour in openvpnmsica.dll and tapctl.exe? I'm not sure if we're going to care for someone who uses a 2.5 msi installer to set up a TAP interface and then runs a 2.3 openvpn.exe on top of it and wonders why it isn't finding the TAP driver - but the question might come up, and I like having good answers... :-) gert
Acked-by: Gert Doering <gert@greenie.muc.de> We have a LGTM from Jon as well, but I'm taking this on me - because I decided I want this in 2.4 as well. Unlikely as it may be, we *will* have people that happen to have a tap adapter on their system and try to run 2.4.x binaries on it... so this is long-term compatibility. Your patch has been applied to the master and release/2.4 branch. commit 6e03336d8a4aada12c4950a9683a483470fe4f15 (master) commit eef040cc909bb0e9bae793b61c2f4f0da7e109d5 (release/2.4) Author: Simon Rozman Date: Tue Oct 16 12:26:27 2018 +0200 Detect TAP interfaces with root-enumerated hardware ID Acked-by: Gert Doering <gert@greenie.muc.de> Message-Id: <20181016102627.18676-5-simon@rozman.si> URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg17762.html Signed-off-by: Gert Doering <gert@greenie.muc.de> -- kind regards, Gert Doering
Hi, > On Tue, Oct 16, 2018 at 12:26:27PM +0200, Simon Rozman wrote: > > This patch extends the TAP interface enumerating to detect the TAP > > interfaces registered using "root\tap0901" hardware ID. Before, only > > TAP interfaces with legacy "tap0901" HWID were detected by > openvpn.exe. > > > > The openvpnmsica.dll and tapctl.exe install TAP interfaces using root- > > enumerated HWIDs, and were not detected by openvpn.exe. > > I do not see a specific reason to *not* apply this patch, but I'm > wondering if you could shed some background light on the changed > behaviour in openvpnmsica.dll and tapctl.exe? The tapctl.exe and openvpnmsica.dll use a simplified interface installation compared to devcon.exe/tapinstall.exe. They assume the driver is already installed and they don't require INF file to create a TAP interface. However, when the interface is installed this way, Windows reports its hardware ID as "root\\tap0901". Whereas, tapinstall.exe installed TAP interfaces report their HWID as "tap0901". That's about the only difference I noticed. (Tested with driver versions 9.21.x and later.) Rather than exploring, what causes the difference and fuelled by Microsoft's recommendation to use root-enumerated HWIDs anyway, I proposed to extend the openvpn.exe's TAP interface detection to accept both: "tap0901" _and_ "root\\tap0901" interfaces. > I'm not sure if we're going to care for someone who uses a 2.5 msi > installer to set up a TAP interface and then runs a 2.3 openvpn.exe on > top of it and wonders why it isn't finding the TAP driver - but the > question might come up, and I like having good answers... :-) Suggest them to remove the TAP interface and reinstall it using tapinstall.exe. The tapinstall.exe should still be able to install 9.22 and later TUN interfaces. Or even better: apply this patch to 2.4 and 2.3 branches (it's a really minor change) and ask them to compile and use the patched version of 2.3. :) Best regards, Simon
Hi, On Sat, Jan 19, 2019 at 05:38:27PM +0000, Simon Rozman wrote: > > > The openvpnmsica.dll and tapctl.exe install TAP interfaces using root- > > > enumerated HWIDs, and were not detected by openvpn.exe. > > > > I do not see a specific reason to *not* apply this patch, but I'm > > wondering if you could shed some background light on the changed > > behaviour in openvpnmsica.dll and tapctl.exe? > > The tapctl.exe and openvpnmsica.dll use a simplified interface installation > compared to devcon.exe/tapinstall.exe. They assume the driver is already > installed and they don't require INF file to create a TAP interface. > However, when the interface is installed this way, Windows reports its > hardware ID as "root\\tap0901". Whereas, tapinstall.exe installed TAP > interfaces report their HWID as "tap0901". That's about the only difference > I noticed. O-kay... :-) - I do not know enough about driver *installation* on Windows to know whether this is all good or there might be dragons lurking. We'll have to test quite a bit, it seems :-) > (Tested with driver versions 9.21.x and later.) > > Rather than exploring, what causes the difference and fuelled by Microsoft's > recommendation to use root-enumerated HWIDs anyway, I proposed to extend the > openvpn.exe's TAP interface detection to accept both: "tap0901" _and_ > "root\\tap0901" interfaces. Works for me. Which is why I ... > Or even better: apply this patch to 2.4 and 2.3 branches (it's a really > minor change) and ask them to compile and use the patched version of 2.3. :) ... applied it to 2.4 as well. If someone struggles with 2.3 on windows (beyond XP), my empathy for them will be close to zero. 2.4 is so much better, especially on windows, that there is no reason to stick to 2.3... (on Linux distributions, sticking to the "distro provided package" might give people 2.3.x for years to come :-( - but this is no argument on Windows). gert
diff --git a/src/openvpn/tun.c b/src/openvpn/tun.c index 948fd17d..5fde2ab8 100644 --- a/src/openvpn/tun.c +++ b/src/openvpn/tun.c @@ -3524,7 +3524,8 @@ get_tap_reg(struct gc_arena *gc) if (status == ERROR_SUCCESS && data_type == REG_SZ) { - if (!strcmp(component_id, TAP_WIN_COMPONENT_ID)) + if (!strcmp(component_id, TAP_WIN_COMPONENT_ID) || + !strcmp(component_id, "root\\" TAP_WIN_COMPONENT_ID)) { struct tap_reg *reg; ALLOC_OBJ_CLEAR_GC(reg, struct tap_reg, gc);