diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7deb182..24bb3e2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -486,6 +486,7 @@ if (WIBO_ENABLE_FIXTURE_TESTS)
         wibo_add_fixture_bin(NAME test_bcrypt SOURCES test/test_bcrypt.c COMPILE_OPTIONS -lbcrypt)
         wibo_add_fixture_bin(NAME test_shlwapi SOURCES test/test_shlwapi.c COMPILE_OPTIONS -lshlwapi)
         wibo_add_fixture_bin(NAME test_ws2 SOURCES test/test_ws2.c COMPILE_OPTIONS -lws2_32)
+        wibo_add_fixture_bin(NAME test_charupperbuff SOURCES test/test_charupperbuff.c COMPILE_OPTIONS -luser32)
         wibo_add_fixture_bin(NAME test_resources SOURCES test/test_resources.c ${WIBO_TEST_BIN_DIR}/test_resources_res.o COMPILE_OPTIONS -lversion)
         wibo_add_fixture_bin(NAME test_threading SOURCES test/test_threading.c)
         wibo_add_fixture_bin(NAME test_temppath SOURCES test/test_temppath.c)
diff --git a/dll/user32.cpp b/dll/user32.cpp
index 1d30c1d..d5f68d4 100644
--- a/dll/user32.cpp
+++ b/dll/user32.cpp
@@ -6,6 +6,7 @@
 #include "kernel32/internal.h"
 #include "modules.h"
 #include "resources.h"
+#include "strutil.h"
 
 #include <cstring>
 
@@ -22,6 +23,24 @@ struct USEROBJECTFLAGS {
 	DWORD dwFlags;
 };
 
+DWORD WINAPI CharUpperBuffW(LPWSTR lpsz, DWORD cchLength) {
+	HOST_CONTEXT_GUARD();
+	DEBUG_LOG("CharUpperBuffW(%p, %u)\n", lpsz, cchLength);
+	if (!lpsz) {
+		return 0;
+	}
+	for (DWORD i = 0; i < cchLength; ++i) {
+		lpsz[i] = wcharToUpper(lpsz[i]);
+	}
+	return cchLength;
+}
+
+LPSTR WINAPI CharNextA(LPCSTR lpsz) {
+	HOST_CONTEXT_GUARD();
+	DEBUG_LOG("CharNextA(%p)\n", lpsz);
+	return const_cast<LPSTR>(*lpsz ? lpsz + 1 : lpsz);
+}
+
 int WINAPI LoadStringA(HMODULE hInstance, UINT uID, LPSTR lpBuffer, int cchBufferMax) {
 	HOST_CONTEXT_GUARD();
 	DEBUG_LOG("LoadStringA(%p, %u, %p, %d)\n", hInstance, uID, lpBuffer, cchBufferMax);
diff --git a/dll/user32.h b/dll/user32.h
index 2fdd833..40d15b8 100644
--- a/dll/user32.h
+++ b/dll/user32.h
@@ -4,6 +4,8 @@
 
 namespace user32 {
 
+DWORD WINAPI CharUpperBuffW(LPWSTR lpsz, DWORD cchLength);
+LPSTR WINAPI CharNextA(LPCSTR lpsz);
 int WINAPI LoadStringA(HMODULE hInstance, UINT uID, LPSTR lpBuffer, int cchBufferMax);
 int WINAPI LoadStringW(HMODULE hInstance, UINT uID, LPWSTR lpBuffer, int cchBufferMax);
 int WINAPI MessageBoxA(HWND hwnd, LPCSTR lpText, LPCSTR lpCaption, UINT uType);
diff --git a/test/test_charupperbuff.c b/test/test_charupperbuff.c
new file mode 100644
index 0000000..455fa8e
--- /dev/null
+++ b/test/test_charupperbuff.c
@@ -0,0 +1,23 @@
+#include <windows.h>
+
+#include "test_assert.h"
+
+int main(void) {
+	char text[] = "ab";
+	WCHAR buffer[] = {'a', 'B', 0, 'c', 'x'};
+	DWORD result;
+
+	result = CharUpperBuffW(buffer, 4);
+	TEST_CHECK_EQ(4, result);
+	TEST_CHECK_EQ('A', buffer[0]);
+	TEST_CHECK_EQ('B', buffer[1]);
+	TEST_CHECK_EQ(0, buffer[2]);
+	TEST_CHECK_EQ('C', buffer[3]);
+	TEST_CHECK_EQ('x', buffer[4]);
+	TEST_CHECK_EQ(0, CharUpperBuffW(NULL, 1));
+
+	TEST_CHECK(CharNextA(text) == text + 1);
+	TEST_CHECK(CharNextA(text + 1) == text + 2);
+	TEST_CHECK(CharNextA(text + 2) == text + 2);
+	return 0;
+}