diff options
Diffstat (limited to 'SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c')
| -rw-r--r-- | SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c | 111 |
1 files changed, 66 insertions, 45 deletions
diff --git a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c index a72b8d9bda..8bd5f2cfa5 100644 --- a/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c +++ b/SecurityPkg/Tcg/Tcg2Pei/Tcg2Pei.c @@ -41,6 +41,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. #include <Library/PerformanceLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/ReportStatusCodeLib.h>
+#include <Library/ResetSystemLib.h>
#include <Library/Tcg2PhysicalPresenceLib.h>
#define PERF_ID_TCG2_PEI 0x3080
@@ -190,60 +191,80 @@ EndofPeiSignalNotifyCallBack ( }
/**
- Set Tpm2HashMask PCD value according to TPM2 PCR bank.
+ Make sure that the current PCR allocations, the TPM supported PCRs,
+ and the PcdTpm2HashMask are all in agreement.
**/
VOID
-SetTpm2HashMask (
+SyncPcrAllocationsAndPcrMask (
VOID
)
{
- EFI_STATUS Status;
- UINT32 ActivePcrBanks;
- TPML_PCR_SELECTION Pcrs;
- UINTN Index;
+ EFI_STATUS Status;
+ EFI_TCG2_EVENT_ALGORITHM_BITMAP TpmHashAlgorithmBitmap;
+ UINT32 TpmActivePcrBanks;
+ UINT32 NewTpmActivePcrBanks;
+ UINT32 Tpm2PcrMask;
+ UINT32 NewTpm2PcrMask;
- DEBUG ((EFI_D_ERROR, "SetTpm2HashMask!\n"));
+ DEBUG ((EFI_D_ERROR, "SyncPcrAllocationsAndPcrMask!\n"));
- Status = Tpm2GetCapabilityPcrs (&Pcrs);
- if (EFI_ERROR (Status)) {
- DEBUG ((EFI_D_ERROR, "Tpm2GetCapabilityPcrs fail!\n"));
- ActivePcrBanks = EFI_TCG2_BOOT_HASH_ALG_SHA1;
- } else {
- DEBUG ((EFI_D_INFO, "Tpm2GetCapabilityPcrs Count - %08x\n", Pcrs.count));
- ActivePcrBanks = 0;
- for (Index = 0; Index < Pcrs.count; Index++) {
- DEBUG ((EFI_D_INFO, "hash - %x\n", Pcrs.pcrSelections[Index].hash));
- switch (Pcrs.pcrSelections[Index].hash) {
- case TPM_ALG_SHA1:
- if (!IsZeroBuffer (Pcrs.pcrSelections[Index].pcrSelect, Pcrs.pcrSelections[Index].sizeofSelect)) {
- ActivePcrBanks |= EFI_TCG2_BOOT_HASH_ALG_SHA1;
- }
- break;
- case TPM_ALG_SHA256:
- if (!IsZeroBuffer (Pcrs.pcrSelections[Index].pcrSelect, Pcrs.pcrSelections[Index].sizeofSelect)) {
- ActivePcrBanks |= EFI_TCG2_BOOT_HASH_ALG_SHA256;
- }
- break;
- case TPM_ALG_SHA384:
- if (!IsZeroBuffer (Pcrs.pcrSelections[Index].pcrSelect, Pcrs.pcrSelections[Index].sizeofSelect)) {
- ActivePcrBanks |= EFI_TCG2_BOOT_HASH_ALG_SHA384;
- }
- break;
- case TPM_ALG_SHA512:
- if (!IsZeroBuffer (Pcrs.pcrSelections[Index].pcrSelect, Pcrs.pcrSelections[Index].sizeofSelect)) {
- ActivePcrBanks |= EFI_TCG2_BOOT_HASH_ALG_SHA512;
- }
- break;
- case TPM_ALG_SM3_256:
- if (!IsZeroBuffer (Pcrs.pcrSelections[Index].pcrSelect, Pcrs.pcrSelections[Index].sizeofSelect)) {
- ActivePcrBanks |= EFI_TCG2_BOOT_HASH_ALG_SM3_256;
- }
- break;
+ //
+ // Determine the current TPM support and the Platform PCR mask.
+ //
+ Status = Tpm2GetCapabilitySupportedAndActivePcrs (&TpmHashAlgorithmBitmap, &TpmActivePcrBanks);
+ ASSERT_EFI_ERROR (Status);
+
+ Tpm2PcrMask = PcdGet32 (PcdTpm2HashMask);
+
+ //
+ // Find the intersection of Pcd support and TPM support.
+ // If banks are missing from the TPM support that are in the PCD, update the PCD.
+ // If banks are missing from the PCD that are active in the TPM, reallocate the banks and reboot.
+ //
+
+ //
+ // If there are active PCR banks that are not supported by the Platform mask,
+ // update the TPM allocations and reboot the machine.
+ //
+ if ((TpmActivePcrBanks & Tpm2PcrMask) != TpmActivePcrBanks) {
+ NewTpmActivePcrBanks = TpmActivePcrBanks & Tpm2PcrMask;
+
+ DEBUG ((EFI_D_INFO, __FUNCTION__" - Reallocating PCR banks from 0x%X to 0x%X.\n", TpmActivePcrBanks, NewTpmActivePcrBanks ));
+ if (NewTpmActivePcrBanks == 0) {
+ DEBUG ((EFI_D_ERROR, __FUNCTION__" - No viable PCRs active! Please set a less restrictive value for PcdTpm2HashMask!\n"));
+ ASSERT (FALSE);
+ } else {
+ Status = Tpm2PcrAllocateBanks (NULL, (UINT32)TpmHashAlgorithmBitmap, NewTpmActivePcrBanks);
+ if (EFI_ERROR (Status)) {
+ //
+ // We can't do much here, but we hope that this doesn't happen.
+ //
+ DEBUG ((EFI_D_ERROR, __FUNCTION__" - Failed to reallocate PCRs!\n"));
+ ASSERT_EFI_ERROR (Status);
}
+ //
+ // Need reset system, since we just called Tpm2PcrAllocateBanks().
+ //
+ ResetCold();
}
}
- Status = PcdSet32S (PcdTpm2HashMask, ActivePcrBanks);
- ASSERT_EFI_ERROR (Status);
+
+ //
+ // If there are any PCRs that claim support in the Platform mask that are
+ // not supported by the TPM, update the mask.
+ //
+ if ((Tpm2PcrMask & TpmHashAlgorithmBitmap) != Tpm2PcrMask) {
+ NewTpm2PcrMask = Tpm2PcrMask & TpmHashAlgorithmBitmap;
+
+ DEBUG ((EFI_D_INFO, __FUNCTION__" - Updating PcdTpm2HashMask from 0x%X to 0x%X.\n", Tpm2PcrMask, NewTpm2PcrMask ));
+ if (NewTpm2PcrMask == 0) {
+ DEBUG ((EFI_D_ERROR, __FUNCTION__" - No viable PCRs supported! Please set a less restrictive value for PcdTpm2HashMask!\n"));
+ ASSERT (FALSE);
+ }
+
+ Status = PcdSet32S (PcdTpm2HashMask, NewTpm2PcrMask);
+ ASSERT_EFI_ERROR (Status);
+ }
}
/**
@@ -767,7 +788,7 @@ PeimEntryMA ( //
// Update Tpm2HashMask according to PCR bank.
//
- SetTpm2HashMask ();
+ SyncPcrAllocationsAndPcrMask ();
if (S3ErrorReport) {
//
|