Add warnings for bad combinations of Device and Interface.

On Linux, the name of the tun/tap interface can be set freely. However,
on most other operating systems, tinc cannot change the name of the
interface. In those situations, it is possible to specify a Device and
an Interface that conflict with each other. On BSD, this can cause
$INTERFACE to be set incorrectly, on Windows, this results in a
potentially unreliable way in which a TAP-Win32 interface is selected.

diff --git a/src/bsd/device.c b/src/bsd/device.c
index 3e9cfb271407f23885711f736fd21be9385ec746..377d4a7b2fff3daaeb9542ed68554b54ba00600d 100644 (file)
--- a/src/bsd/device.c
+++ b/src/bsd/device.c
@@ -75,6 +75,8 @@ static bool setup_device(void) {
 
        if(!get_config_string(lookup_config(config_tree, "Interface"), &iface))
                iface = xstrdup(strrchr(device, '/') ? strrchr(device, '/') + 1 : device);
+       else if(strcmp(iface, strrchr(device, '/') ? strrchr(device, '/') + 1 : device))
+               logger(LOG_WARNING, "Warning: Interface does not match Device. $INTERFACE might be set incorrectly.");
 
        if(get_config_string(lookup_config(config_tree, "DeviceType"), &type)) {
                if(!strcasecmp(type, "tun"))

diff --git a/src/cygwin/device.c b/src/cygwin/device.c
index b582a6a962c99be9fb729af0b6f5d1f8fa60ea22..47867a493e8edbb87bfcf53ded1c4ba3a11cfb09 100644 (file)
--- a/src/cygwin/device.c
+++ b/src/cygwin/device.c
@@ -61,6 +61,9 @@ static bool setup_device(void) {
        get_config_string(lookup_config(config_tree, "Device"), &device);
        get_config_string(lookup_config(config_tree, "Interface"), &iface);
 
+       if(device && interface)
+               logger(LOG_WARNING, "Warning: both Device and Interface specified, results may not be as expected");
+
        /* Open registry and look for network adapters */
 
        if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {

diff --git a/src/mingw/device.c b/src/mingw/device.c
index 49b833abbe708f440aaf7af2307e676b22b1ffb2..b77282ad9c1771814be74a7ffaea47a47359ed9c 100644 (file)
--- a/src/mingw/device.c
+++ b/src/mingw/device.c
@@ -113,6 +113,9 @@ static bool setup_device(void) {
        get_config_string(lookup_config(config_tree, "Device"), &device);
        get_config_string(lookup_config(config_tree, "Interface"), &iface);
 
+       if(device && interface)
+               logger(LOG_WARNING, "Warning: both Device and Interface specified, results may not be as expected");
+
        /* Open registry and look for network adapters */
 
        if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, NETWORK_CONNECTIONS_KEY, 0, KEY_READ, &key)) {