1
2 /*
3 * Licensed Materials - Property of IBM
4 *
5 * trousers - An open source TCG Software Stack
6 *
7 * (C) Copyright International Business Machines Corp. 2004-2006
8 *
9 */
10
11
12 #include <stdlib.h>
13 #include <stdio.h>
14 #include <string.h>
15 #include <unistd.h>
16 #include <sys/types.h>
17 #include <sys/mman.h>
18 #include <errno.h>
19
20 #include "trousers/tss.h"
21 #include "trousers/trousers.h"
22 #include "trousers_types.h"
23 #include "trousers_types.h"
24 #include "spi_utils.h"
25 #include "capabilities.h"
26 #include "tsplog.h"
27 #include "obj.h"
28
29
30 UINT16
get_num_pcrs(TSS_HCONTEXT tspContext)31 get_num_pcrs(TSS_HCONTEXT tspContext)
32 {
33 TSS_RESULT result;
34 static UINT16 ret = 0;
35 UINT32 subCap;
36 UINT32 respSize;
37 BYTE *resp;
38
39 if (ret != 0)
40 return ret;
41
42 subCap = endian32(TPM_CAP_PROP_PCR);
43 if ((result = TCS_API(tspContext)->GetTPMCapability(tspContext, TPM_CAP_PROPERTY,
44 sizeof(UINT32), (BYTE *)&subCap,
45 &respSize, &resp))) {
46 if ((resp = (BYTE *)getenv("TSS_DEFAULT_NUM_PCRS")) == NULL)
47 return TSS_DEFAULT_NUM_PCRS;
48
49 /* don't set ret here, next time we may be connected */
50 return atoi((char *)resp);
51 }
52
53 ret = (UINT16)Decode_UINT32(resp);
54 free(resp);
55
56 return ret;
57 }
58
59 TSS_RESULT
pcrs_calc_composite(TPM_PCR_SELECTION * select,TPM_PCRVALUE * arrayOfPcrs,TPM_DIGEST * digestOut)60 pcrs_calc_composite(TPM_PCR_SELECTION *select, TPM_PCRVALUE *arrayOfPcrs, TPM_DIGEST *digestOut)
61 {
62 UINT32 size, index;
63 BYTE mask;
64 BYTE hashBlob[1024];
65 UINT32 numPCRs = 0;
66 UINT64 offset = 0;
67 UINT64 sizeOffset = 0;
68
69 if (select->sizeOfSelect > 0) {
70 sizeOffset = 0;
71 Trspi_LoadBlob_PCR_SELECTION(&sizeOffset, hashBlob, select);
72 offset = sizeOffset + 4;
73
74 for (size = 0; size < select->sizeOfSelect; size++) {
75 for (index = 0, mask = 1; index < 8; index++, mask = mask << 1) {
76 if (select->pcrSelect[size] & mask) {
77 memcpy(&hashBlob[(numPCRs * TPM_SHA1_160_HASH_LEN) + offset],
78 arrayOfPcrs[index + (size << 3)].digest,
79 TPM_SHA1_160_HASH_LEN);
80 numPCRs++;
81 }
82 }
83 }
84
85 if (numPCRs > 0) {
86 offset += (numPCRs * TPM_SHA1_160_HASH_LEN);
87 UINT32ToArray(numPCRs * TPM_SHA1_160_HASH_LEN, &hashBlob[sizeOffset]);
88
89 return Trspi_Hash(TSS_HASH_SHA1, offset, hashBlob, digestOut->digest);
90 }
91 }
92
93 return TSPERR(TSS_E_INTERNAL_ERROR);
94 }
95
96 TSS_RESULT
pcrs_sanity_check_selection(TSS_HCONTEXT tspContext,struct tr_pcrs_obj * pcrs,TPM_PCR_SELECTION * select)97 pcrs_sanity_check_selection(TSS_HCONTEXT tspContext,
98 struct tr_pcrs_obj *pcrs,
99 TPM_PCR_SELECTION *select)
100 {
101 UINT16 num_pcrs, bytes_to_hold;
102
103 if ((num_pcrs = get_num_pcrs(tspContext)) == 0)
104 return TSPERR(TSS_E_INTERNAL_ERROR);
105
106 bytes_to_hold = num_pcrs / 8;
107
108 /* Is the current select object going to be interpretable by the TPM?
109 * If the select object is of a size greater than the one the TPM
110 * wants, just calculate the composite hash and let the TPM return an
111 * error code to the user. If its less than the size of the one the
112 * TPM wants, add extra zero bytes until its the right size. */
113 if (bytes_to_hold > select->sizeOfSelect) {
114 if ((select->pcrSelect = realloc(select->pcrSelect, bytes_to_hold)) == NULL) {
115 LogError("malloc of %hu bytes failed.", bytes_to_hold);
116 return TSPERR(TSS_E_OUTOFMEMORY);
117 }
118 /* set the newly allocated bytes to 0 */
119 __tspi_memset(&select->pcrSelect[select->sizeOfSelect], 0,
120 bytes_to_hold - select->sizeOfSelect);
121 select->sizeOfSelect = bytes_to_hold;
122
123 /* realloc the pcr array as well */
124 if ((pcrs->pcrs = realloc(pcrs->pcrs,
125 (bytes_to_hold * 8) * TPM_SHA1_160_HASH_LEN)) == NULL) {
126 LogError("malloc of %d bytes failed.",
127 (bytes_to_hold * 8) * TPM_SHA1_160_HASH_LEN);
128 return TSPERR(TSS_E_OUTOFMEMORY);
129 }
130 }
131
132 #ifdef TSS_DEBUG
133 {
134 int i;
135 for (i = 0; i < select->sizeOfSelect * 8; i++) {
136 if (select->pcrSelect[i/8] & (1 << (i % 8))) {
137 LogDebug("PCR%d: Selected", i);
138 LogBlobData(APPID, TPM_SHA1_160_HASH_LEN,
139 (unsigned char *)&pcrs->pcrs[i]);
140 } else {
141 LogDebug("PCR%d: Not Selected", i);
142 }
143 }
144 }
145 #endif
146
147 return TSS_SUCCESS;
148 }
149