Don't set Legacy IP address on Windows tunnel interface within OpenConnect itself

The pre-existing Windows routing connection script (vpnc-script-win.js) was
not able to reliably set the Legacy IP address of the tunnel interface, so
we've been setting it in OpenConnect itself since
60d1f092e35f05217f1c96823c4f1b86c7915bbd.

As of https://gitlab.com/openconnect/vpnc-scripts/-/merge_requests/26, we've
got vpnc-script-win.js setting the Legacy IP address correctly, and IPv6 as
well. We should leave this as the script's responsibility for
cross-platform consistency.

Signed-off-by: Daniel Lenski <dlenski@gmail.com>

diff --git a/wintun.c b/wintun.c
index f575e594e1bcf9acea8a9139866d1978093d8860..78b48084c705ae4916a235cc6a8113cb95087294 100644 (file)
--- a/wintun.c
+++ b/wintun.c
@@ -140,50 +140,6 @@ intptr_t open_wintun(struct openconnect_info *vpninfo, char *guid, wchar_t *wnam
                }
        }
 
-       if (vpninfo->ip_info.addr) {
-               /*
-                * For now, vpnc-script-win.js depends on us setting the Legacy IP
-                * address on the interface. Which of course assumes there *is* a
-                * Legacy IP configuration not just IPv6. This is kind of horrid
-                * but stay compatible with it for now. In order to set the address
-                * up, we may first need to *remove* it from any other interface
-                * that has it, even if the other interface is down. Testing with
-                * a TAP-Windows interface and then Wintun was failing until I made
-                * it explicitly delete the IP address first. The later call to
-                * CreateUnicastIpAddressEntry() was apparently succeeding, but
-                * wasn't changing anything. Yay Windows!
-                */
-               MIB_UNICASTIPADDRESS_ROW AddressRow;
-               InitializeUnicastIpAddressEntry(&AddressRow);
-               WintunGetAdapterLUID(vpninfo->wintun_adapter, &AddressRow.InterfaceLuid);
-               AddressRow.Address.Ipv4.sin_family = AF_INET;
-               AddressRow.Address.Ipv4.sin_addr.S_un.S_addr = htonl(inet_addr(vpninfo->ip_info.addr));
-               AddressRow.OnLinkPrefixLength = 32;
-
-               PMIB_UNICASTIPADDRESS_TABLE pipTable = NULL;
-               DWORD LastError = GetUnicastIpAddressTable(AF_INET, &pipTable);
-               if (LastError == ERROR_SUCCESS) {
-                       for (int i = 0; i < pipTable->NumEntries; i++) {
-                               if (pipTable->Table[i].Address.Ipv4.sin_addr.S_un.S_addr ==
-                                   AddressRow.Address.Ipv4.sin_addr.S_un.S_addr) {
-                                       DeleteUnicastIpAddressEntry(&pipTable->Table[i]);
-                               }
-                       }
-               }
-
-               LastError = CreateUnicastIpAddressEntry(&AddressRow);
-               if (LastError != ERROR_SUCCESS) {
-                       char *errstr = openconnect__win32_strerror(GetLastError());
-                       vpn_progress(vpninfo, PRG_ERR,
-                                    _("Failed to set Legacy IP address on Wintun: %s\n"),
-                                    errstr);
-                       free(errstr);
-
-                       ret = OPEN_TUN_HARDFAIL;
-                       goto out;
-               }
-       }
-
        vpninfo->wintun_session = WintunStartSession(vpninfo->wintun_adapter, 0x400000);
        if (!vpninfo->wintun_session) {
                char *errstr = openconnect__win32_strerror(GetLastError());