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-rw-r--r--NetworkPkg/Library/DxeNetLib/DxeNetLib.c130
1 files changed, 112 insertions, 18 deletions
diff --git a/NetworkPkg/Library/DxeNetLib/DxeNetLib.c b/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
index fd4a9e15a8..01c13c08d2 100644
--- a/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
+++ b/NetworkPkg/Library/DxeNetLib/DxeNetLib.c
@@ -3,6 +3,7 @@
Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
(C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
+Copyright (c) Microsoft Corporation
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
@@ -31,6 +32,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
#include <Library/DevicePathLib.h>
#include <Library/PrintLib.h>
#include <Library/UefiLib.h>
+#include <Protocol/Rng.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)
@@ -127,6 +129,25 @@ GLOBAL_REMOVE_IF_UNREFERENCED VLAN_DEVICE_PATH mNetVlanDevicePathTemplate = {
0
};
+//
+// These represent UEFI SPEC defined algorithms that should be supported by
+// the RNG protocol and are generally considered secure.
+//
+// The order of the algorithms in this array is important. This order is the order
+// in which the algorithms will be tried by the RNG protocol.
+// If your platform needs to use a specific algorithm for the random number generator,
+// then you should place that algorithm first in the array.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_GUID *mSecureHashAlgorithms[] = {
+ &gEfiRngAlgorithmSp80090Ctr256Guid, // SP800-90A DRBG CTR using AES-256
+ &gEfiRngAlgorithmSp80090Hmac256Guid, // SP800-90A DRBG HMAC using SHA-256
+ &gEfiRngAlgorithmSp80090Hash256Guid, // SP800-90A DRBG Hash using SHA-256
+ &gEfiRngAlgorithmArmRndr, // unspecified SP800-90A DRBG via ARM RNDR register
+ &gEfiRngAlgorithmRaw, // Raw data from NRBG (or TRNG)
+};
+
+#define SECURE_HASH_ALGORITHMS_SIZE (sizeof (mSecureHashAlgorithms) / sizeof (EFI_GUID *))
+
/**
Locate the handles that support SNP, then open one of them
to send the syslog packets. The caller isn't required to close
@@ -884,34 +905,107 @@ Ip6Swap128 (
}
/**
- Initialize a random seed using current time and monotonic count.
+ Generate a Random output data given a length.
- Get current time and monotonic count first. Then initialize a random seed
- based on some basic mathematics operation on the hour, day, minute, second,
- nanosecond and year of the current time and the monotonic count value.
+ @param[out] Output - The buffer to store the generated random data.
+ @param[in] OutputLength - The length of the output buffer.
- @return The random seed initialized with current time.
+ @retval EFI_SUCCESS On Success
+ @retval EFI_INVALID_PARAMETER Pointer is null or size is zero
+ @retval EFI_NOT_FOUND RNG protocol not found
+ @retval Others Error from RngProtocol->GetRNG()
+ @return Status code
**/
-UINT32
+EFI_STATUS
EFIAPI
-NetRandomInitSeed (
- VOID
+PseudoRandom (
+ OUT VOID *Output,
+ IN UINTN OutputLength
)
{
- EFI_TIME Time;
- UINT32 Seed;
- UINT64 MonotonicCount;
+ EFI_RNG_PROTOCOL *RngProtocol;
+ EFI_STATUS Status;
+ UINTN AlgorithmIndex;
+
+ if ((Output == NULL) || (OutputLength == 0)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = gBS->LocateProtocol (&gEfiRngProtocolGuid, NULL, (VOID **)&RngProtocol);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Failed to locate EFI_RNG_PROTOCOL: %r\n", Status));
+ ASSERT_EFI_ERROR (Status);
+ return Status;
+ }
+
+ if (PcdGetBool (PcdEnforceSecureRngAlgorithms)) {
+ for (AlgorithmIndex = 0; AlgorithmIndex < SECURE_HASH_ALGORITHMS_SIZE; AlgorithmIndex++) {
+ Status = RngProtocol->GetRNG (RngProtocol, mSecureHashAlgorithms[AlgorithmIndex], OutputLength, (UINT8 *)Output);
+ if (!EFI_ERROR (Status)) {
+ //
+ // Secure Algorithm was supported on this platform
+ //
+ return EFI_SUCCESS;
+ } else if (Status == EFI_UNSUPPORTED) {
+ //
+ // Secure Algorithm was not supported on this platform
+ //
+ DEBUG ((DEBUG_ERROR, "Failed to generate random data using secure algorithm %d: %r\n", AlgorithmIndex, Status));
+
+ //
+ // Try the next secure algorithm
+ //
+ continue;
+ } else {
+ //
+ // Some other error occurred
+ //
+ DEBUG ((DEBUG_ERROR, "Failed to generate random data using secure algorithm %d: %r\n", AlgorithmIndex, Status));
+ ASSERT_EFI_ERROR (Status);
+ return Status;
+ }
+ }
+
+ //
+ // If we get here, we failed to generate random data using any secure algorithm
+ // Platform owner should ensure that at least one secure algorithm is supported
+ //
+ ASSERT_EFI_ERROR (Status);
+ return Status;
+ }
+
+ //
+ // Lets try using the default algorithm (which may not be secure)
+ //
+ Status = RngProtocol->GetRNG (RngProtocol, NULL, OutputLength, (UINT8 *)Output);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "%a failed to generate random data: %r\n", __func__, Status));
+ ASSERT_EFI_ERROR (Status);
+ return Status;
+ }
- gRT->GetTime (&Time, NULL);
- Seed = (Time.Hour << 24 | Time.Day << 16 | Time.Minute << 8 | Time.Second);
- Seed ^= Time.Nanosecond;
- Seed ^= Time.Year << 7;
+ return EFI_SUCCESS;
+}
+
+/**
+ Generate a 32-bit pseudo-random number.
- gBS->GetNextMonotonicCount (&MonotonicCount);
- Seed += (UINT32)MonotonicCount;
+ @param[out] Output - The buffer to store the generated random number.
- return Seed;
+ @retval EFI_SUCCESS On Success
+ @retval EFI_NOT_FOUND RNG protocol not found
+ @retval Others Error from RngProtocol->GetRNG()
+
+ @return Status code
+**/
+EFI_STATUS
+EFIAPI
+PseudoRandomU32 (
+ OUT UINT32 *Output
+ )
+{
+ return PseudoRandom (Output, sizeof (*Output));
}
/**