From e0bdb75c67290d6851a4d2509fcfafaf9ef0e696 Mon Sep 17 00:00:00 2001
From: ShenYage <shenyage1@huawei.com>
Date: Fri, 28 Feb 2025 16:18:39 +0800
Subject: [PATCH 2/2] NetworkPkg: DxeNetLib: SECURITY PATCH CVE-2023-45237
 Relared Patch

This commit is a patch for CVE-2023-45237. Using RngLib to generate a stronger pseudoRandom number for NetRandomInitSeed().

Signed-off-by: ShenYage <shenyage1@huawei.com>
---
 NetworkPkg/Library/DxeNetLib/DxeNetLib.c   | 18 ++++++++++++------
 NetworkPkg/Library/DxeNetLib/DxeNetLib.inf |  1 +
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/NetworkPkg/Library/DxeNetLib/DxeNetLib.c b/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
index fd4a9e15..d24038e8 100644
--- a/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
+++ b/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
@@ -31,6 +31,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/DevicePathLib.h>
 #include <Library/PrintLib.h>
 #include <Library/UefiLib.h>
+#include <Library/RngLib.h>
 
 #define NIC_ITEM_CONFIG_SIZE  (sizeof (NIC_IP4_CONFIG_INFO) + sizeof (EFI_IP4_ROUTE_TABLE) * MAX_IP4_CONFIG_IN_VARIABLE)
 #define DEFAULT_ZERO_START    ((UINTN) ~0)
@@ -902,14 +903,19 @@ NetRandomInitSeed (
   EFI_TIME  Time;
   UINT32    Seed;
   UINT64    MonotonicCount;
+  UINT32    RandomVal;
 
-  gRT->GetTime (&Time, NULL);
-  Seed  = (Time.Hour << 24 | Time.Day << 16 | Time.Minute << 8 | Time.Second);
-  Seed ^= Time.Nanosecond;
-  Seed ^= Time.Year << 7;
+  if (GetRandomNumber32(&RandomVal)) {
+    Seed = RandomVal;
+  } else {
+    gRT->GetTime (&Time, NULL);
+    Seed  = (Time.Hour << 24 | Time.Day << 16 | Time.Minute << 8 | Time.Second);
+    Seed ^= Time.Nanosecond;
+    Seed ^= Time.Year << 7;
 
-  gBS->GetNextMonotonicCount (&MonotonicCount);
-  Seed += (UINT32)MonotonicCount;
+    gBS->GetNextMonotonicCount (&MonotonicCount);
+    Seed += (UINT32)MonotonicCount;
+  }
 
   return Seed;
 }
diff --git a/NetworkPkg/Library/DxeNetLib/DxeNetLib.inf b/NetworkPkg/Library/DxeNetLib/DxeNetLib.inf
index 8145d256..ce90aa5e 100644
--- a/NetworkPkg/Library/DxeNetLib/DxeNetLib.inf
+++ b/NetworkPkg/Library/DxeNetLib/DxeNetLib.inf
@@ -43,6 +43,7 @@
   MemoryAllocationLib
   DevicePathLib
   PrintLib
+  RngLib
 
 
 [Guids]
-- 
2.33.0

