From c465cf5cf3fbd09caf82d2c34fc6f127f5648b48 Mon Sep 17 00:00:00 2001
From: Oliver Steffen <osteffen@redhat.com>
Date: Thu, 7 Nov 2024 11:36:22 +0100
Subject: [PATCH 2/2] OvmfPkg/ArmVirtPkg: Add a Fallback RNG (RH only)

RH-Author: Oliver Steffen <osteffen@redhat.com>
RH-MergeRequest: 104: OvmfPkg: Add a Fallback RNG (RH only)
RH-Jira: RHEL-66236
RH-Acked-by: Gerd Hoffmann <kraxel@redhat.com>
RH-Commit: [2/2] d7748d697e522ab5ef70702da53241db71e602fe

Since the pixiefail CVE fix, the network stack requires a random number
generator.
In case there is no hardware random number generator available,
have the Platform Boot Manager install a pseudo RNG to ensure
the network can be used.

This patch adds the fallback rng which was introduced in a
previous commit also to the ArmVirtPkg PlatformBootManagerLib.

Signed-off-by: Oliver Steffen <osteffen@redhat.com>
---
 ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c       | 5 +++++
 .../PlatformBootManagerLib/PlatformBootManagerLib.inf        | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
index 1848042f86..c4cfbfc7f6 100644
--- a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
+++ b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBm.c
@@ -29,6 +29,7 @@
 #include <Guid/GlobalVariable.h>
 #include <Guid/RootBridgesConnectedEventGroup.h>
 #include <Guid/SerialPortLibVendor.h>
+#include "FallbackRng.h"
 
 #include "PlatformBm.h"
 
@@ -793,6 +794,8 @@ PlatformBootManagerBeforeConsole (
   // instances on Virtio PCI RNG devices.
   //
   FilterAndProcess (&gEfiPciIoProtocolGuid, IsVirtioPciRng, Connect);
+
+  FallbackRngCheckAndInstall ();
 }
 
 /**
@@ -814,6 +817,8 @@ PlatformBootManagerAfterConsole (
 {
   RETURN_STATUS Status;
 
+  FallbackRngPrintWarning ();
+
   //
   // Show the splash screen.
   //
diff --git a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
index 997eb1a442..d4ea9bef60 100644
--- a/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
+++ b/ArmVirtPkg/Library/PlatformBootManagerLib/PlatformBootManagerLib.inf
@@ -27,6 +27,8 @@
   PlatformBm.c
   PlatformBm.h
   QemuKernel.c
+  ../../../OvmfPkg/Library/PlatformBootManagerLib/FallbackRng.h
+  ../../../OvmfPkg/Library/PlatformBootManagerLib/FallbackRng.c
 
 [Packages]
   ArmVirtPkg/ArmVirtPkg.dec
@@ -53,6 +55,7 @@
   UefiBootServicesTableLib
   UefiLib
   UefiRuntimeServicesTableLib
+  RngLib
 
 [FixedPcd]
   gEfiMdePkgTokenSpaceGuid.PcdUartDefaultBaudRate
@@ -69,9 +72,11 @@
   gEfiGlobalVariableGuid
   gRootBridgesConnectedEventGroupGuid
   gUefiShellFileGuid
+  gEfiRngAlgorithmRaw
 
 [Protocols]
   gEfiFirmwareVolume2ProtocolGuid
   gEfiGraphicsOutputProtocolGuid
   gEfiPciRootBridgeIoProtocolGuid
   gVirtioDeviceProtocolGuid
+  gEfiRngProtocolGuid
-- 
2.45.2