TpmComm.c revision 0c18794ea4289f03fefc7117b56740414cc0536c 
1/** @file
2  Utility functions used by TPM Dxe driver.
3
4Copyright (c) 2005 - 2010, Intel Corporation. All rights reserved.<BR>
5This program and the accompanying materials
6are licensed and made available under the terms and conditions of the BSD License
7which accompanies this distribution.  The full text of the license may be found at
8http://opensource.org/licenses/bsd-license.php
9
10THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
12
13**/
14
15#include <IndustryStandard/Tpm12.h>
16#include <IndustryStandard/UefiTcgPlatform.h>
17#include <Library/TpmCommLib.h>
18#include <Library/BaseMemoryLib.h>
19
20#include "TpmComm.h"
21
22/**
23  Extend a TPM PCR.
24
25  @param[in]  TpmHandle       TPM handle.
26  @param[in]  DigestToExtend  The 160 bit value representing the event to be recorded.
27  @param[in]  PcrIndex        The PCR to be updated.
28  @param[out] NewPcrValue     New PCR value after extend.
29
30  @retval EFI_SUCCESS         Operation completed successfully.
31  @retval EFI_DEVICE_ERROR    The command was unsuccessful.
32
33**/
34EFI_STATUS
35TpmCommExtend (
36  IN      TIS_TPM_HANDLE            TpmHandle,
37  IN      TPM_DIGEST                *DigestToExtend,
38  IN      TPM_PCRINDEX              PcrIndex,
39     OUT  TPM_DIGEST                *NewPcrValue
40  )
41{
42  EFI_STATUS                        Status;
43  TPM_DIGEST                        NewValue;
44  TPM_RQU_COMMAND_HDR               CmdHdr;
45  TPM_RSP_COMMAND_HDR               RspHdr;
46
47  if (NewPcrValue == NULL) {
48    NewPcrValue = &NewValue;
49  }
50
51  CmdHdr.tag = TPM_TAG_RQU_COMMAND;
52  CmdHdr.paramSize =
53    sizeof (CmdHdr) + sizeof (PcrIndex) + sizeof (*DigestToExtend);
54  CmdHdr.ordinal = TPM_ORD_Extend;
55  Status = TisPcExecute (
56             TpmHandle,
57             "%h%d%r%/%h%r",
58             &CmdHdr,
59             PcrIndex,
60             DigestToExtend,
61             (UINTN)sizeof (*DigestToExtend),
62             &RspHdr,
63             NewPcrValue,
64             (UINTN)sizeof (*NewPcrValue)
65             );
66  if (EFI_ERROR (Status)) {
67    return Status;
68  }
69  if (RspHdr.returnCode != 0) {
70    return EFI_DEVICE_ERROR;
71  }
72  return EFI_SUCCESS;
73}
74
75/**
76  Get TPM capability flags.
77
78  @param[in]  TpmHandle    TPM handle.
79  @param[in]  FlagSubcap   Flag subcap.
80  @param[out] FlagBuffer   Pointer to the buffer for returned flag structure.
81  @param[in]  FlagSize     Size of the buffer.
82
83  @retval EFI_SUCCESS      Operation completed successfully.
84  @retval EFI_DEVICE_ERROR The command was unsuccessful.
85
86**/
87EFI_STATUS
88TpmCommGetFlags (
89  IN      TIS_TPM_HANDLE            TpmHandle,
90  IN      UINT32                    FlagSubcap,
91     OUT  VOID                      *FlagBuffer,
92  IN      UINTN                     FlagSize
93  )
94{
95  EFI_STATUS                        Status;
96  TPM_RQU_COMMAND_HDR               CmdHdr;
97  TPM_RSP_COMMAND_HDR               RspHdr;
98  UINT32                            Size;
99
100  CmdHdr.tag = TPM_TAG_RQU_COMMAND;
101  CmdHdr.paramSize = sizeof (CmdHdr) + sizeof (UINT32) * 3;
102  CmdHdr.ordinal = TPM_ORD_GetCapability;
103
104  Status = TisPcExecute (
105             TpmHandle,
106             "%h%d%d%d%/%h%d%r",
107             &CmdHdr,
108             TPM_CAP_FLAG,
109             sizeof (FlagSubcap),
110             FlagSubcap,
111             &RspHdr,
112             &Size,
113             FlagBuffer,
114             FlagSize
115             );
116  if (EFI_ERROR (Status)) {
117    return Status;
118  }
119  if (RspHdr.returnCode != 0) {
120    return EFI_DEVICE_ERROR;
121  }
122  return EFI_SUCCESS;
123}
124
125/**
126  Add a new entry to the Event Log.
127
128  @param[in, out] EventLogPtr   Pointer to the Event Log data.
129  @param[in, out] LogSize       Size of the Event Log.
130  @param[in]      MaxSize       Maximum size of the Event Log.
131  @param[in]      NewEventHdr   Pointer to a TCG_PCR_EVENT_HDR data structure.
132  @param[in]      NewEventData  Pointer to the new event data.
133
134  @retval EFI_SUCCESS           The new event log entry was added.
135  @retval EFI_OUT_OF_RESOURCES  No enough memory to log the new event.
136
137**/
138EFI_STATUS
139TpmCommLogEvent (
140  IN OUT  UINT8                     **EventLogPtr,
141  IN OUT  UINTN                     *LogSize,
142  IN      UINTN                     MaxSize,
143  IN      TCG_PCR_EVENT_HDR         *NewEventHdr,
144  IN      UINT8                     *NewEventData
145  )
146{
147  UINT32                            NewLogSize;
148
149  NewLogSize = sizeof (*NewEventHdr) + NewEventHdr->EventSize;
150  if (NewLogSize + *LogSize > MaxSize) {
151    return EFI_OUT_OF_RESOURCES;
152  }
153
154  *EventLogPtr += *LogSize;
155  *LogSize += NewLogSize;
156  CopyMem (*EventLogPtr, NewEventHdr, sizeof (*NewEventHdr));
157  CopyMem (
158    *EventLogPtr + sizeof (*NewEventHdr),
159    NewEventData,
160    NewEventHdr->EventSize
161    );
162  return EFI_SUCCESS;
163}
164