NetworkPkg: Ip6Dxe: SECURITY PATCH CVE-2023-45232 Unit Tests

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=4537
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=4538

Unit tests to confirm that..

Infinite loop when parsing unknown options in the Destination Options
header

and

Infinite loop when parsing a PadN option in the Destination Options
header

... have been patched

This patch tests the following functions:
Ip6IsOptionValid

Cc: Saloni Kasbekar <saloni.kasbekar@intel.com>
Cc: Zachary Clark-williams <zachary.clark-williams@intel.com>

Signed-off-by: Doug Flick [MSFT] <doug.edk2@gmail.com>
Reviewed-by: Saloni Kasbekar <saloni.kasbekar@intel.com>

NetworkPkg/Ip6Dxe/GoogleTest/Ip6OptionGoogleTest.h

@@ -0,0 +1,40 @@
+/** @file
+  Exposes the functions needed to test the Ip6Option module.
+
+  Copyright (c) Microsoft Corporation
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef IP6_OPTION_HEADER_GOOGLE_TEST_H_
+#define IP6_OPTION_HEADER_GOOGLE_TEST_H_
+
+#include <Uefi.h>
+#include "../Ip6Impl.h"
+
+/**
+  Validate the IP6 option format for both the packets we received
+  and that we will transmit. It will compute the ICMPv6 error message fields
+  if the option is malformatted.
+
+  @param[in]  IpSb              The IP6 service data.
+  @param[in]  Packet            The to be validated packet.
+  @param[in]  Option            The first byte of the option.
+  @param[in]  OptionLen         The length of the whole option.
+  @param[in]  Pointer           Identifies the octet offset within
+                                the invoking packet where the error was detected.
+
+
+  @retval TRUE     The option is properly formatted.
+  @retval FALSE    The option is malformatted.
+
+**/
+BOOLEAN
+Ip6IsOptionValid (
+  IN IP6_SERVICE  *IpSb,
+  IN NET_BUF      *Packet,
+  IN UINT8        *Option,
+  IN UINT16       OptionLen,
+  IN UINT32       Pointer
+  );
+
+#endif // __IP6_OPTION_HEADER_GOOGLE_TEST_H__