xref: /openbmc/u-boot/cmd/tpm-v2.c (revision da9c3392)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2018 Bootlin
4  * Author: Miquel Raynal <miquel.raynal@bootlin.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <log.h>
10 #include <mapmem.h>
11 #include <tpm-common.h>
12 #include <tpm-v2.h>
13 #include "tpm-user-utils.h"
14 
15 static int do_tpm2_startup(cmd_tbl_t *cmdtp, int flag, int argc,
16 			   char * const argv[])
17 {
18 	enum tpm2_startup_types mode;
19 
20 	if (argc != 2)
21 		return CMD_RET_USAGE;
22 
23 	if (!strcasecmp("TPM2_SU_CLEAR", argv[1])) {
24 		mode = TPM2_SU_CLEAR;
25 	} else if (!strcasecmp("TPM2_SU_STATE", argv[1])) {
26 		mode = TPM2_SU_STATE;
27 	} else {
28 		printf("Couldn't recognize mode string: %s\n", argv[1]);
29 		return CMD_RET_FAILURE;
30 	}
31 
32 	return report_return_code(tpm2_startup(mode));
33 }
34 
35 static int do_tpm2_self_test(cmd_tbl_t *cmdtp, int flag, int argc,
36 			     char * const argv[])
37 {
38 	enum tpm2_yes_no full_test;
39 
40 	if (argc != 2)
41 		return CMD_RET_USAGE;
42 
43 	if (!strcasecmp("full", argv[1])) {
44 		full_test = TPMI_YES;
45 	} else if (!strcasecmp("continue", argv[1])) {
46 		full_test = TPMI_NO;
47 	} else {
48 		printf("Couldn't recognize test mode: %s\n", argv[1]);
49 		return CMD_RET_FAILURE;
50 	}
51 
52 	return report_return_code(tpm2_self_test(full_test));
53 }
54 
55 static int do_tpm2_clear(cmd_tbl_t *cmdtp, int flag, int argc,
56 			 char * const argv[])
57 {
58 	u32 handle = 0;
59 	const char *pw = (argc < 3) ? NULL : argv[2];
60 	const ssize_t pw_sz = pw ? strlen(pw) : 0;
61 
62 	if (argc < 2 || argc > 3)
63 		return CMD_RET_USAGE;
64 
65 	if (pw_sz > TPM2_DIGEST_LEN)
66 		return -EINVAL;
67 
68 	if (!strcasecmp("TPM2_RH_LOCKOUT", argv[1]))
69 		handle = TPM2_RH_LOCKOUT;
70 	else if (!strcasecmp("TPM2_RH_PLATFORM", argv[1]))
71 		handle = TPM2_RH_PLATFORM;
72 	else
73 		return CMD_RET_USAGE;
74 
75 	return report_return_code(tpm2_clear(handle, pw, pw_sz));
76 }
77 
78 static int do_tpm2_pcr_extend(cmd_tbl_t *cmdtp, int flag, int argc,
79 			      char * const argv[])
80 {
81 	struct udevice *dev;
82 	struct tpm_chip_priv *priv;
83 	u32 index = simple_strtoul(argv[1], NULL, 0);
84 	void *digest = map_sysmem(simple_strtoul(argv[2], NULL, 0), 0);
85 	int ret;
86 	u32 rc;
87 
88 	if (argc != 3)
89 		return CMD_RET_USAGE;
90 
91 	ret = uclass_first_device_err(UCLASS_TPM, &dev);
92 	if (ret)
93 		return ret;
94 
95 	priv = dev_get_uclass_priv(dev);
96 	if (!priv)
97 		return -EINVAL;
98 
99 	if (index >= priv->pcr_count)
100 		return -EINVAL;
101 
102 	rc = tpm2_pcr_extend(index, digest);
103 
104 	unmap_sysmem(digest);
105 
106 	return report_return_code(rc);
107 }
108 
109 static int do_tpm_pcr_read(cmd_tbl_t *cmdtp, int flag, int argc,
110 			   char * const argv[])
111 {
112 	struct udevice *dev;
113 	struct tpm_chip_priv *priv;
114 	u32 index, rc;
115 	unsigned int updates;
116 	void *data;
117 	int ret;
118 
119 	if (argc != 3)
120 		return CMD_RET_USAGE;
121 
122 	ret = uclass_first_device_err(UCLASS_TPM, &dev);
123 	if (ret)
124 		return ret;
125 
126 	priv = dev_get_uclass_priv(dev);
127 	if (!priv)
128 		return -EINVAL;
129 
130 	index = simple_strtoul(argv[1], NULL, 0);
131 	if (index >= priv->pcr_count)
132 		return -EINVAL;
133 
134 	data = map_sysmem(simple_strtoul(argv[2], NULL, 0), 0);
135 
136 	rc = tpm2_pcr_read(index, priv->pcr_select_min, data, &updates);
137 	if (!rc) {
138 		printf("PCR #%u content (%d known updates):\n", index, updates);
139 		print_byte_string(data, TPM2_DIGEST_LEN);
140 	}
141 
142 	unmap_sysmem(data);
143 
144 	return report_return_code(rc);
145 }
146 
147 static int do_tpm_get_capability(cmd_tbl_t *cmdtp, int flag, int argc,
148 				 char * const argv[])
149 {
150 	u32 capability, property, rc;
151 	u8 *data;
152 	size_t count;
153 	int i, j;
154 
155 	if (argc != 5)
156 		return CMD_RET_USAGE;
157 
158 	capability = simple_strtoul(argv[1], NULL, 0);
159 	property = simple_strtoul(argv[2], NULL, 0);
160 	data = map_sysmem(simple_strtoul(argv[3], NULL, 0), 0);
161 	count = simple_strtoul(argv[4], NULL, 0);
162 
163 	rc = tpm2_get_capability(capability, property, data, count);
164 	if (rc)
165 		goto unmap_data;
166 
167 	printf("Capabilities read from TPM:\n");
168 	for (i = 0; i < count; i++) {
169 		printf("Property 0x");
170 		for (j = 0; j < 4; j++)
171 			printf("%02x", data[(i * 8) + j]);
172 		printf(": 0x");
173 		for (j = 4; j < 8; j++)
174 			printf("%02x", data[(i * 8) + j]);
175 		printf("\n");
176 	}
177 
178 unmap_data:
179 	unmap_sysmem(data);
180 
181 	return report_return_code(rc);
182 }
183 
184 static int do_tpm_dam_reset(cmd_tbl_t *cmdtp, int flag, int argc,
185 			    char *const argv[])
186 {
187 	const char *pw = (argc < 2) ? NULL : argv[1];
188 	const ssize_t pw_sz = pw ? strlen(pw) : 0;
189 
190 	if (argc > 2)
191 		return CMD_RET_USAGE;
192 
193 	if (pw_sz > TPM2_DIGEST_LEN)
194 		return -EINVAL;
195 
196 	return report_return_code(tpm2_dam_reset(pw, pw_sz));
197 }
198 
199 static int do_tpm_dam_parameters(cmd_tbl_t *cmdtp, int flag, int argc,
200 				 char *const argv[])
201 {
202 	const char *pw = (argc < 5) ? NULL : argv[4];
203 	const ssize_t pw_sz = pw ? strlen(pw) : 0;
204 	/*
205 	 * No Dictionary Attack Mitigation (DAM) means:
206 	 * maxtries = 0xFFFFFFFF, recovery_time = 1, lockout_recovery = 0
207 	 */
208 	unsigned long int max_tries;
209 	unsigned long int recovery_time;
210 	unsigned long int lockout_recovery;
211 
212 	if (argc < 4 || argc > 5)
213 		return CMD_RET_USAGE;
214 
215 	if (pw_sz > TPM2_DIGEST_LEN)
216 		return -EINVAL;
217 
218 	if (strict_strtoul(argv[1], 0, &max_tries))
219 		return CMD_RET_USAGE;
220 
221 	if (strict_strtoul(argv[2], 0, &recovery_time))
222 		return CMD_RET_USAGE;
223 
224 	if (strict_strtoul(argv[3], 0, &lockout_recovery))
225 		return CMD_RET_USAGE;
226 
227 	log(LOGC_NONE, LOGL_INFO, "Changing dictionary attack parameters:\n");
228 	log(LOGC_NONE, LOGL_INFO, "- maxTries: %lu", max_tries);
229 	log(LOGC_NONE, LOGL_INFO, "- recoveryTime: %lu\n", recovery_time);
230 	log(LOGC_NONE, LOGL_INFO, "- lockoutRecovery: %lu\n", lockout_recovery);
231 
232 	return report_return_code(tpm2_dam_parameters(pw, pw_sz, max_tries,
233 						      recovery_time,
234 						      lockout_recovery));
235 }
236 
237 static cmd_tbl_t tpm2_commands[] = {
238 	U_BOOT_CMD_MKENT(info, 0, 1, do_tpm_info, "", ""),
239 	U_BOOT_CMD_MKENT(init, 0, 1, do_tpm_init, "", ""),
240 	U_BOOT_CMD_MKENT(startup, 0, 1, do_tpm2_startup, "", ""),
241 	U_BOOT_CMD_MKENT(self_test, 0, 1, do_tpm2_self_test, "", ""),
242 	U_BOOT_CMD_MKENT(clear, 0, 1, do_tpm2_clear, "", ""),
243 	U_BOOT_CMD_MKENT(pcr_extend, 0, 1, do_tpm2_pcr_extend, "", ""),
244 	U_BOOT_CMD_MKENT(pcr_read, 0, 1, do_tpm_pcr_read, "", ""),
245 	U_BOOT_CMD_MKENT(get_capability, 0, 1, do_tpm_get_capability, "", ""),
246 	U_BOOT_CMD_MKENT(dam_reset, 0, 1, do_tpm_dam_reset, "", ""),
247 	U_BOOT_CMD_MKENT(dam_parameters, 0, 1, do_tpm_dam_parameters, "", ""),
248 };
249 
250 cmd_tbl_t *get_tpm_commands(unsigned int *size)
251 {
252 	*size = ARRAY_SIZE(tpm2_commands);
253 
254 	return tpm2_commands;
255 }
256 
257 U_BOOT_CMD(tpm, CONFIG_SYS_MAXARGS, 1, do_tpm, "Issue a TPMv2.x command",
258 "<command> [<arguments>]\n"
259 "\n"
260 "info\n"
261 "    Show information about the TPM.\n"
262 "init\n"
263 "    Initialize the software stack. Always the first command to issue.\n"
264 "startup <mode>\n"
265 "    Issue a TPM2_Startup command.\n"
266 "    <mode> is one of:\n"
267 "        * TPM2_SU_CLEAR (reset state)\n"
268 "        * TPM2_SU_STATE (preserved state)\n"
269 "self_test <type>\n"
270 "    Test the TPM capabilities.\n"
271 "    <type> is one of:\n"
272 "        * full (perform all tests)\n"
273 "        * continue (only check untested tests)\n"
274 "clear <hierarchy>\n"
275 "    Issue a TPM2_Clear command.\n"
276 "    <hierarchy> is one of:\n"
277 "        * TPM2_RH_LOCKOUT\n"
278 "        * TPM2_RH_PLATFORM\n"
279 "pcr_extend <pcr> <digest_addr>\n"
280 "    Extend PCR #<pcr> with digest at <digest_addr>.\n"
281 "    <pcr>: index of the PCR\n"
282 "    <digest_addr>: address of a 32-byte SHA256 digest\n"
283 "pcr_read <pcr> <digest_addr>\n"
284 "    Read PCR #<pcr> to memory address <digest_addr>.\n"
285 "    <pcr>: index of the PCR\n"
286 "    <digest_addr>: address to store the a 32-byte SHA256 digest\n"
287 "get_capability <capability> <property> <addr> <count>\n"
288 "    Read and display <count> entries indexed by <capability>/<property>.\n"
289 "    Values are 4 bytes long and are written at <addr>.\n"
290 "    <capability>: capability\n"
291 "    <property>: property\n"
292 "    <addr>: address to store <count> entries of 4 bytes\n"
293 "    <count>: number of entries to retrieve\n"
294 "  dam_reset_counter [<password>]\n"
295 "    - If the TPM is not in a LOCKOUT state, reset the internal error\n"
296 "      counter (TPMv2 only)\n"
297 "  dam_set_parameters <maxTries> <recoveryTime> <lockoutRecovery> [<password>]\n"
298 "    - If the TPM is not in a LOCKOUT state, set the dictionary attack\n"
299 "      parameters:\n"
300 "          * maxTries: maximum number of failures before lockout.\n"
301 "                          0 means always locking.\n"
302 "          * recoveryTime: time before decrementation of the error counter,\n"
303 "                          0 means no lockout.\n"
304 "          * lockoutRecovery: time of a lockout (before the next try)\n"
305 "                          0 means a reboot is needed.\n"
306 );
307