1 /* Microsoft Reference Implementation for TPM 2.0
2 *
3 * The copyright in this software is being made available under the BSD License,
4 * included below. This software may be subject to other third party and
5 * contributor rights, including patent rights, and no such rights are granted
6 * under this license.
7 *
8 * Copyright (c) Microsoft Corporation
9 *
10 * All rights reserved.
11 *
12 * BSD License
13 *
14 * Redistribution and use in source and binary forms, with or without modification,
15 * are permitted provided that the following conditions are met:
16 *
17 * Redistributions of source code must retain the above copyright notice, this list
18 * of conditions and the following disclaimer.
19 *
20 * Redistributions in binary form must reproduce the above copyright notice, this
21 * list of conditions and the following disclaimer in the documentation and/or
22 * other materials provided with the distribution.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ""AS IS""
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
27 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
28 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
31 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35 #include "Tpm.h"
36 #include "NV_Extend_fp.h"
37
38 #if CC_NV_Extend // Conditional expansion of this file
39
40 /*(See part 3 specification)
41 // Write to a NV index
42 */
43 // Return Type: TPM_RC
44 // TPM_RC_ATTRIBUTES the TPMA_NV_EXTEND attribute is not SET in
45 // the Index referenced by 'nvIndex'
46 // TPM_RC_NV_AUTHORIZATION the authorization was valid but the
47 // authorizing entity ('authHandle')
48 // is not allowed to write to the Index
49 // referenced by 'nvIndex'
50 // TPM_RC_NV_LOCKED the Index referenced by 'nvIndex' is locked
51 // for writing
52 TPM_RC
TPM2_NV_Extend(NV_Extend_In * in)53 TPM2_NV_Extend(
54 NV_Extend_In *in // IN: input parameter list
55 )
56 {
57 TPM_RC result;
58 NV_REF locator;
59 NV_INDEX *nvIndex = NvGetIndexInfo(in->nvIndex, &locator);
60
61 TPM2B_DIGEST oldDigest;
62 TPM2B_DIGEST newDigest;
63 HASH_STATE hashState;
64
65 // Input Validation
66
67 // Common access checks, NvWriteAccessCheck() may return TPM_RC_NV_AUTHORIZATION
68 // or TPM_RC_NV_LOCKED
69 result = NvWriteAccessChecks(in->authHandle,
70 in->nvIndex,
71 nvIndex->publicArea.attributes);
72 if(result != TPM_RC_SUCCESS)
73 return result;
74
75 // Make sure that this is an extend index
76 if(!IsNvExtendIndex(nvIndex->publicArea.attributes))
77 return TPM_RCS_ATTRIBUTES + RC_NV_Extend_nvIndex;
78
79 // Internal Data Update
80
81 // Perform the write.
82 oldDigest.t.size = CryptHashGetDigestSize(nvIndex->publicArea.nameAlg);
83 pAssert(oldDigest.t.size <= sizeof(oldDigest.t.buffer));
84 if(IS_ATTRIBUTE(nvIndex->publicArea.attributes, TPMA_NV, WRITTEN))
85 {
86 NvGetIndexData(nvIndex, locator, 0, oldDigest.t.size, oldDigest.t.buffer);
87 }
88 else
89 {
90 MemorySet(oldDigest.t.buffer, 0, oldDigest.t.size);
91 }
92 // Start hash
93 newDigest.t.size = CryptHashStart(&hashState, nvIndex->publicArea.nameAlg);
94
95 // Adding old digest
96 CryptDigestUpdate2B(&hashState, &oldDigest.b);
97
98 // Adding new data
99 CryptDigestUpdate2B(&hashState, &in->data.b);
100
101 // Complete hash
102 CryptHashEnd2B(&hashState, &newDigest.b);
103
104 // Write extended hash back.
105 // Note, this routine will SET the TPMA_NV_WRITTEN attribute if necessary
106 return NvWriteIndexData(nvIndex, 0, newDigest.t.size, newDigest.t.buffer);
107 }
108
109 #endif // CC_NV_Extend