From 3f9f0e2a961a11f7aeab296b4b72acae54411029 Mon Sep 17 00:00:00 2001
From: Eric Kohl <eric.kohl@reactos.org>
Date: Sun, 8 Mar 2026 12:22:47 +0100
Subject: [PATCH] [PSDK][DHCSCSVC][IPCONFIG] Add DhcpHandlePnpEvent stub and
 use it in ipconfig

Ipconfig uses DhcpHandlePnpEvent to notify the dhcp client of a changed class id.
---
 base/applications/network/ipconfig/ipconfig.c | 27 ++++++++++++++++++-
 base/services/dhcpcsvc/dhcpcsvc.c             | 11 +++++---
 sdk/include/psdk/dhcpcapi.h                   | 17 +++++++++++-
 3 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/base/applications/network/ipconfig/ipconfig.c b/base/applications/network/ipconfig/ipconfig.c
index e9d9cd91c11..eaf16c83a2b 100644
--- a/base/applications/network/ipconfig/ipconfig.c
+++ b/base/applications/network/ipconfig/ipconfig.c
@@ -1244,8 +1244,10 @@ SetClassId(
     ULONG ret = 0;
     WCHAR szFriendlyName[MAX_PATH];
     WCHAR szKeyName[256];
+    WCHAR szUnicodeAdapterName[MAX_ADAPTER_NAME_LENGTH + 4];
     MIB_IFROW mibEntry;
     HKEY hKey;
+    DHCP_PNP_EVENT PnpEvent;
 
     ConResPrintf(StdOut, IDS_HEADER);
 
@@ -1313,8 +1315,31 @@ SetClassId(
         if (pszClassId == NULL)
             pszClassId = L"";
 
-        RegSetValueExW(hKey, L"DhcpClassId", 0, REG_SZ, (LPBYTE)pszClassId, (wcslen(pszClassId) + 1) * sizeof(WCHAR));
+        ret = RegSetValueExW(hKey, L"DhcpClassId", 0, REG_SZ, (LPBYTE)pszClassId, (wcslen(pszClassId) + 1) * sizeof(WCHAR));
         RegCloseKey(hKey);
+        if (ret != ERROR_SUCCESS)
+        {
+            ConResPrintf(StdOut, IDS_DHCPSETIDERROR, szFriendlyName);
+            DoFormatMessage(ret);
+            goto done;
+        }
+
+        mbstowcs(szUnicodeAdapterName, pFoundAdapter->AdapterName, strlen(pFoundAdapter->AdapterName) + 1);
+
+        ZeroMemory(&PnpEvent, sizeof(PnpEvent));
+        PnpEvent.Unknown5 = 1;
+
+        ret = DhcpHandlePnPEvent(0,
+                                 1,
+                                 szUnicodeAdapterName,
+                                 &PnpEvent,
+                                 0);
+        if (ret != ERROR_SUCCESS)
+        {
+            ConResPrintf(StdOut, IDS_DHCPSETIDERROR, szFriendlyName);
+            DoFormatMessage(ret);
+            goto done;
+        }
 
         ConResPrintf(StdOut, IDS_DHCPSETIDSUCCESS, szFriendlyName);
     }
diff --git a/base/services/dhcpcsvc/dhcpcsvc.c b/base/services/dhcpcsvc/dhcpcsvc.c
index dd2bee797bf..3166e4cd7fc 100644
--- a/base/services/dhcpcsvc/dhcpcsvc.c
+++ b/base/services/dhcpcsvc/dhcpcsvc.c
@@ -8,6 +8,7 @@
 
 #include <rosdhcp.h>
 #include <winsvc.h>
+#include <dhcpcapi.h>
 
 #define NDEBUG
 #include <debug.h>
@@ -168,11 +169,15 @@ DhcpHandlePnPEvent(
     _In_ DWORD Unknown1,
     _In_ DWORD Unknown2,
     _In_ PWSTR AdapterName,
-    _In_ DWORD Unknown4,
+    _In_ PDHCP_PNP_EVENT PnpEvent,
     _In_ DWORD Unknown5)
 {
-    DPRINT1("DhcpHandlePnPEvent(%lx %lx %S %lx %lx)\n",
-            Unknown1, Unknown2, AdapterName, Unknown4, Unknown5);
+    DPRINT1("DhcpHandlePnPEvent(%lx %lx %S %p %lx)\n",
+            Unknown1, Unknown2, AdapterName, PnpEvent, Unknown5);
+
+    if ((Unknown1 != 0) || (Unknown2 != 1) || (PnpEvent == NULL) || (Unknown5 != 0))
+        return ERROR_INVALID_PARAMETER;
+
     return 0;
 }
 
diff --git a/sdk/include/psdk/dhcpcapi.h b/sdk/include/psdk/dhcpcapi.h
index 6a90f6267de..ec876d9804d 100644
--- a/sdk/include/psdk/dhcpcapi.h
+++ b/sdk/include/psdk/dhcpcapi.h
@@ -5,6 +5,21 @@
 extern "C" {
 #endif
 
+typedef struct _DHCP_PNP_EVENT
+{
+    DWORD Unknown1;
+    DWORD Unknown2;
+    DWORD Unknown3;
+    DWORD Unknown4;
+    DWORD Unknown5;
+    DWORD Unknown6;
+    DWORD Unknown7;
+    DWORD Unknown8;
+    DWORD Unknown9;
+    DWORD Unknown10;
+    DWORD Unknown11;
+} DHCP_PNP_EVENT, *PDHCP_PNP_EVENT;
+
 DWORD
 APIENTRY
 DhcpAcquireParameters(
@@ -24,7 +39,7 @@ DhcpHandlePnPEvent(
     _In_ DWORD Unknown1,
     _In_ DWORD Unknown2,
     _In_ LPWSTR AdapterName,
-    _In_ DWORD Unknown4,
+    _In_ PDHCP_PNP_EVENT PnpEvent,
     _In_ DWORD Unknown5);
 
 DWORD