ipc: use more clever PnP enumerator

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

3 files changed, 16 insertions, 60 deletions

diff --git a/src/Makefile b/src/Makefile
index b91ade8..0533910 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -62,7 +62,7 @@ ifeq ($(PLATFORM),windows)
 CC := x86_64-w64-mingw32-clang
 WINDRES := $(shell $(CC) $(CFLAGS) -print-prog-name=windres 2>/dev/null)
 CFLAGS += -Iwincompat/include -include wincompat/compat.h -DWINVER=0x0601 -D_WIN32_WINNT=0x0601 -flto
-LDLIBS += -lws2_32 -lsetupapi -lole32 -ladvapi32 -Lwincompat
+LDLIBS += -lws2_32 -lsetupapi -lole32 -ladvapi32 -lntdll -Lwincompat
 LDFLAGS += -flto -Wl,--dynamicbase -Wl,--nxcompat -Wl,--tsaware -mconsole
 LDFLAGS += -Wl,--major-os-version=6 -Wl,--minor-os-version=1 -Wl,--major-subsystem-version=6 -Wl,--minor-subsystem-version=1
 # The use of -Wl,/delayload: here implies we're using llvm-mingw
diff --git a/src/ipc-windows.h b/src/ipc-windows.h
index 59fa3a9..d237fc9 100644
--- a/src/ipc-windows.h
+++ b/src/ipc-windows.h
@@ -19,10 +19,11 @@
 static bool have_cached_kernel_interfaces;
 static struct hashtable cached_kernel_interfaces;
 static const DEVPROPKEY devpkey_name = DEVPKEY_WG_NAME;
+extern bool is_win7;
 
 static int kernel_get_wireguard_interfaces(struct string_list *list)
 {
-	HDEVINFO dev_info = SetupDiGetClassDevsExW(&GUID_DEVCLASS_NET, NULL, NULL, DIGCF_PRESENT, NULL, NULL, NULL);
+	HDEVINFO dev_info = SetupDiGetClassDevsExW(&GUID_DEVCLASS_NET, is_win7 ? L"ROOT\\WIREGUARD" : L"SWD\\WireGuard", NULL, DIGCF_PRESENT, NULL, NULL, NULL);
 	bool will_have_cached_kernel_interfaces = true;
 
 	if (dev_info == INVALID_HANDLE_VALUE) {
@@ -31,9 +32,8 @@ static int kernel_get_wireguard_interfaces(struct string_list *list)
 	}
 
 	for (DWORD i = 0;; ++i) {
-		bool found = false;
-		DWORD buf_len = 0, value_type;
-		WCHAR *buf = NULL, adapter_name[MAX_ADAPTER_NAME];
+		DWORD buf_len;
+		WCHAR adapter_name[MAX_ADAPTER_NAME];
 		SP_DEVINFO_DATA dev_info_data = { .cbSize = sizeof(SP_DEVINFO_DATA) };
 		DEVPROPTYPE prop_type;
 		ULONG status, problem_code;
@@ -46,31 +46,6 @@ static int kernel_get_wireguard_interfaces(struct string_list *list)
 			continue;
 		}
 
-		while (!SetupDiGetDeviceRegistryPropertyW(dev_info, &dev_info_data, SPDRP_HARDWAREID, &value_type, (BYTE *)buf, buf_len, &buf_len)) {
-			free(buf);
-			buf = NULL;
-			if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
-				break;
-			buf = malloc(buf_len);
-			if (!buf)
-				break;
-		}
-
-		if (!buf || value_type != REG_MULTI_SZ || buf_len < sizeof(*buf) * 2 || buf[buf_len / sizeof(*buf) - 1] || buf[buf_len / sizeof(*buf) - 2]) {
-			free(buf);
-			continue;
-		}
-
-		for (WCHAR *item = buf; *item; item += wcslen(item) + 1) {
-			if (!_wcsicmp(item, L"wireguard")) {
-				found = true;
-				break;
-			}
-		}
-		free(buf);
-		if (!found)
-			continue;
-
 		if (!SetupDiGetDevicePropertyW(dev_info, &dev_info_data, &devpkey_name,
 					       &prop_type, (PBYTE)adapter_name,
 					       sizeof(adapter_name), NULL, 0) ||
@@ -155,14 +130,14 @@ err_hash:
 		}
 	}
 
-	dev_info = SetupDiGetClassDevsExW(&GUID_DEVCLASS_NET, NULL, NULL, DIGCF_PRESENT, NULL, NULL, NULL);
+	dev_info = SetupDiGetClassDevsExW(&GUID_DEVCLASS_NET, is_win7 ? L"ROOT\\WIREGUARD" : L"SWD\\WireGuard", NULL, DIGCF_PRESENT, NULL, NULL, NULL);
 	if (dev_info == INVALID_HANDLE_VALUE)
 		return NULL;
 
 	for (DWORD i = 0; !interfaces; ++i) {
-		bool found = false;
-		DWORD buf_len = 0, value_type;
-		WCHAR *buf = NULL, adapter_name[MAX_ADAPTER_NAME];
+		bool found;
+		DWORD buf_len;
+		WCHAR *buf, adapter_name[MAX_ADAPTER_NAME];
 		SP_DEVINFO_DATA dev_info_data = { .cbSize = sizeof(SP_DEVINFO_DATA) };
 		DEVPROPTYPE prop_type;
 		char *interface_name;
@@ -173,31 +148,6 @@ err_hash:
 			continue;
 		}
 
-		while (!SetupDiGetDeviceRegistryPropertyW(dev_info, &dev_info_data, SPDRP_HARDWAREID, &value_type, (BYTE *)buf, buf_len, &buf_len)) {
-			free(buf);
-			buf = NULL;
-			if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
-				break;
-			buf = malloc(buf_len);
-			if (!buf)
-				break;
-		}
-
-		if (!buf || value_type != REG_MULTI_SZ || buf_len < sizeof(*buf) * 2 || buf[buf_len / sizeof(*buf) - 1] || buf[buf_len / sizeof(*buf) - 2]) {
-			free(buf);
-			continue;
-		}
-
-		for (WCHAR *item = buf; *item; item += wcslen(item) + 1) {
-			if (!_wcsicmp(item, L"wireguard")) {
-				found = true;
-				break;
-			}
-		}
-		free(buf);
-		if (!found)
-			continue;
-
 		if (!SetupDiGetDevicePropertyW(dev_info, &dev_info_data, &devpkey_name,
 					       &prop_type, (PBYTE)adapter_name,
 					       sizeof(adapter_name), NULL, 0) ||
diff --git a/src/wincompat/init.c b/src/wincompat/init.c
index f744f69..f92c0a9 100644
--- a/src/wincompat/init.c
+++ b/src/wincompat/init.c
@@ -10,16 +10,22 @@
 #define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x4
 #endif
 
+extern void NTAPI RtlGetNtVersionNumbers(DWORD *major, DWORD *minor, DWORD *build);
+bool is_win7 = false;
+
 __attribute__((constructor)) static void init(void)
 {
 	char *colormode;
-	DWORD console_mode;
+	DWORD console_mode, major, minor;
 	HANDLE stdout_handle;
 	WSADATA wsaData;
 
 	if (!SetDllDirectoryA("") || !SetDefaultDllDirectories(LOAD_LIBRARY_SEARCH_SYSTEM32))
 		abort();
 
+	RtlGetNtVersionNumbers(&major, &minor, NULL);
+	is_win7 = (major == 6 && minor <= 1) || major < 6;
+
 	WSAStartup(MAKEWORD(2, 2), &wsaData);
 
 	stdout_handle = GetStdHandle(STD_OUTPUT_HANDLE); // We don't close this.