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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) International Business Machines  Corp., 2009
4  * Copyright (c) 2016-2019 Petr Vorel <pvorel@suse.cz>
5  *
6  * Authors: Mimi Zohar <zohar@us.ibm.com>
7  *
8  * Calculate a SHA1 boot aggregate value based on the TPM 1.2
9  * binary_bios_measurements.
10  */
11 
12 #include "config.h"
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <sys/types.h>
16 #include <sys/stat.h>
17 #include <fcntl.h>
18 #include <string.h>
19 #include <unistd.h>
20 #include <limits.h>
21 
22 #include "tst_test.h"
23 #include "tst_safe_stdio.h"
24 
25 #if HAVE_LIBCRYPTO
26 #include <openssl/sha.h>
27 #include <openssl/evp.h>
28 
29 #define MAX_EVENT_SIZE (1024*1024)
30 #define EVENT_HEADER_SIZE 32
31 #define MAX_EVENT_DATA_SIZE (MAX_EVENT_SIZE - EVENT_HEADER_SIZE)
32 #define NUM_PCRS 8		/*  PCR registers 0-7 in boot aggregate */
33 
34 static char *debug;
35 static char *file;
36 
37 static unsigned char boot_aggregate[SHA_DIGEST_LENGTH];
38 
39 static struct {
40 	struct {
41 		u_int32_t pcr;
42 		u_int32_t type;
43 		u_int8_t digest[SHA_DIGEST_LENGTH];
44 		u_int32_t len;
45 	} header __attribute__ ((packed));
46 	char *data;
47 } event;
48 
49 static struct {
50 	unsigned char digest[SHA_DIGEST_LENGTH];
51 } pcr[NUM_PCRS];
52 
display_sha1_digest(unsigned char * pcr)53 static void display_sha1_digest(unsigned char *pcr)
54 {
55 	int i;
56 
57 	for (i = 0; i < SHA_DIGEST_LENGTH; i++)
58 		printf("%02x", *(pcr + i) & 0xff);
59 	printf("\n");
60 }
61 
do_test(void)62 static void do_test(void)
63 {
64 	FILE *fp;
65 #if OPENSSL_VERSION_NUMBER > 0x030000000L
66 	EVP_MD_CTX *c = NULL;
67 #else
68 	SHA_CTX c;
69 #endif
70 	int i;
71 
72 	if (!file)
73 		tst_brk(TBROK, "missing binary_bios_measurement file, specify with -f");
74 
75 	fp = SAFE_FOPEN(file, "r");
76 
77 	/* Initialize psuedo PCR registers 0 - 7 */
78 	for (i = 0; i < NUM_PCRS; i++)
79 		memset(&pcr[i].digest, 0, SHA_DIGEST_LENGTH);
80 
81 	event.data = malloc(MAX_EVENT_DATA_SIZE);
82 	if (!event.data)
83 		tst_brk(TBROK, "cannot allocate memory");
84 
85 	/* Extend the pseudo PCRs with the event digest */
86 	while (fread(&event, sizeof(event.header), 1, fp)) {
87 		if (debug) {
88 			printf("%03u ", event.header.pcr);
89 			display_sha1_digest(event.header.digest);
90 		}
91 
92 		if (event.header.pcr < NUM_PCRS) {
93 #if OPENSSL_VERSION_NUMBER > 0x030000000L
94 			if ((c = EVP_MD_CTX_new()) == NULL)
95 				tst_brk(TBROK, "can't get new context");
96 
97 			EVP_DigestInit_ex(c, EVP_sha1(), NULL);
98 			EVP_DigestUpdate(c, pcr[event.header.pcr].digest,
99 					 SHA_DIGEST_LENGTH);
100 			EVP_DigestUpdate(c, event.header.digest, SHA_DIGEST_LENGTH);
101 			EVP_DigestFinal_ex(c, pcr[event.header.pcr].digest, NULL);
102 			EVP_MD_CTX_free(c);
103 #else
104 			SHA1_Init(&c);
105 			SHA1_Update(&c, pcr[event.header.pcr].digest,
106 				    SHA_DIGEST_LENGTH);
107 			SHA1_Update(&c, event.header.digest,
108 				    SHA_DIGEST_LENGTH);
109 			SHA1_Final(pcr[event.header.pcr].digest, &c);
110 #endif
111 		}
112 
113 #if MAX_EVENT_DATA_SIZE < USHRT_MAX
114 		if (event.header.len > MAX_EVENT_DATA_SIZE) {
115 			tst_res(TWARN, "error event too long");
116 			break;
117 		}
118 #endif
119 		if (fread(event.data, event.header.len, 1, fp) != 1)
120 			tst_brk(TBROK, "failed to read 1 byte");
121 	}
122 
123 	SAFE_FCLOSE(fp);
124 	free(event.data);
125 
126 	/* Extend the boot aggregate with the pseudo PCR digest values */
127 	memset(&boot_aggregate, 0, SHA_DIGEST_LENGTH);
128 
129 #if OPENSSL_VERSION_NUMBER > 0x030000000L
130 	EVP_DigestInit_ex(c, EVP_sha1(), NULL);
131 #else
132 	SHA1_Init(&c);
133 #endif
134 
135 	for (i = 0; i < NUM_PCRS; i++) {
136 		if (debug) {
137 			printf("PCR-%2.2x: ", i);
138 			display_sha1_digest(pcr[i].digest);
139 		}
140 #if OPENSSL_VERSION_NUMBER > 0x030000000L
141 		EVP_DigestUpdate(c, pcr[i].digest, SHA_DIGEST_LENGTH);
142 #else
143 		SHA1_Update(&c, pcr[i].digest, SHA_DIGEST_LENGTH);
144 #endif
145 	}
146 
147 #if OPENSSL_VERSION_NUMBER > 0x030000000L
148 	EVP_MD_CTX_free(c);
149 #else
150 	SHA1_Final(boot_aggregate, &c);
151 #endif
152 
153 	printf("sha1:");
154 	display_sha1_digest(boot_aggregate);
155 	tst_res(TPASS, "found sha1 hash");
156 }
157 
158 static struct tst_option options[] = {
159 	{"d", &debug, "Enable debug"},
160 	{"f:", &file, "binary_bios_measurement file (required)\n"},
161 	{}
162 };
163 
164 static struct tst_test test = {
165 	.needs_root = 1,
166 	.test_all = do_test,
167 	.options = options,
168 };
169 
170 #else
171 TST_TEST_TCONF("libcrypto and openssl development packages required");
172 #endif
173