xref: /openbmc/u-boot/cmd/tpm-common.c (revision 81930bd2)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2013 The Chromium OS Authors.
4  */
5 
6 #include <common.h>
7 #include <command.h>
8 #include <dm.h>
9 #include <environment.h>
10 #include <malloc.h>
11 #include <asm/unaligned.h>
12 #include <linux/string.h>
13 #include <tpm-common.h>
14 #include "tpm-user-utils.h"
15 
16 static struct udevice *tpm_dev;
17 
18 /**
19  * Print a byte string in hexdecimal format, 16-bytes per line.
20  *
21  * @param data		byte string to be printed
22  * @param count		number of bytes to be printed
23  */
24 void print_byte_string(u8 *data, size_t count)
25 {
26 	int i, print_newline = 0;
27 
28 	for (i = 0; i < count; i++) {
29 		printf(" %02x", data[i]);
30 		print_newline = (i % 16 == 15);
31 		if (print_newline)
32 			putc('\n');
33 	}
34 	/* Avoid duplicated newline at the end */
35 	if (!print_newline)
36 		putc('\n');
37 }
38 
39 /**
40  * Convert a text string of hexdecimal values into a byte string.
41  *
42  * @param bytes		text string of hexdecimal values with no space
43  *			between them
44  * @param data		output buffer for byte string.  The caller has to make
45  *			sure it is large enough for storing the output.  If
46  *			NULL is passed, a large enough buffer will be allocated,
47  *			and the caller must free it.
48  * @param count_ptr	output variable for the length of byte string
49  * Return: pointer to output buffer
50  */
51 void *parse_byte_string(char *bytes, u8 *data, size_t *count_ptr)
52 {
53 	char byte[3];
54 	size_t count, length;
55 	int i;
56 
57 	if (!bytes)
58 		return NULL;
59 	length = strlen(bytes);
60 	count = length / 2;
61 
62 	if (!data)
63 		data = malloc(count);
64 	if (!data)
65 		return NULL;
66 
67 	byte[2] = '\0';
68 	for (i = 0; i < length; i += 2) {
69 		byte[0] = bytes[i];
70 		byte[1] = bytes[i + 1];
71 		data[i / 2] = (u8)simple_strtoul(byte, NULL, 16);
72 	}
73 
74 	if (count_ptr)
75 		*count_ptr = count;
76 
77 	return data;
78 }
79 
80 /**
81  * report_return_code() - Report any error and return failure or success
82  *
83  * @param return_code	TPM command return code
84  * Return: value of enum command_ret_t
85  */
86 int report_return_code(int return_code)
87 {
88 	if (return_code) {
89 		printf("Error: %d\n", return_code);
90 		return CMD_RET_FAILURE;
91 	} else {
92 		return CMD_RET_SUCCESS;
93 	}
94 }
95 
96 /**
97  * Return number of values defined by a type string.
98  *
99  * @param type_str	type string
100  * Return: number of values of type string
101  */
102 int type_string_get_num_values(const char *type_str)
103 {
104 	return strlen(type_str);
105 }
106 
107 /**
108  * Return total size of values defined by a type string.
109  *
110  * @param type_str	type string
111  * Return: total size of values of type string, or 0 if type string
112  *  contains illegal type character.
113  */
114 size_t type_string_get_space_size(const char *type_str)
115 {
116 	size_t size;
117 
118 	for (size = 0; *type_str; type_str++) {
119 		switch (*type_str) {
120 		case 'b':
121 			size += 1;
122 			break;
123 		case 'w':
124 			size += 2;
125 			break;
126 		case 'd':
127 			size += 4;
128 			break;
129 		default:
130 			return 0;
131 		}
132 	}
133 
134 	return size;
135 }
136 
137 /**
138  * Allocate a buffer large enough to hold values defined by a type
139  * string.  The caller has to free the buffer.
140  *
141  * @param type_str	type string
142  * @param count		pointer for storing size of buffer
143  * Return: pointer to buffer or NULL on error
144  */
145 void *type_string_alloc(const char *type_str, u32 *count)
146 {
147 	void *data;
148 	size_t size;
149 
150 	size = type_string_get_space_size(type_str);
151 	if (!size)
152 		return NULL;
153 	data = malloc(size);
154 	if (data)
155 		*count = size;
156 
157 	return data;
158 }
159 
160 /**
161  * Pack values defined by a type string into a buffer.  The buffer must have
162  * large enough space.
163  *
164  * @param type_str	type string
165  * @param values	text strings of values to be packed
166  * @param data		output buffer of values
167  * Return: 0 on success, non-0 on error
168  */
169 int type_string_pack(const char *type_str, char * const values[],
170 		     u8 *data)
171 {
172 	size_t offset;
173 	u32 value;
174 
175 	for (offset = 0; *type_str; type_str++, values++) {
176 		value = simple_strtoul(values[0], NULL, 0);
177 		switch (*type_str) {
178 		case 'b':
179 			data[offset] = value;
180 			offset += 1;
181 			break;
182 		case 'w':
183 			put_unaligned_be16(value, data + offset);
184 			offset += 2;
185 			break;
186 		case 'd':
187 			put_unaligned_be32(value, data + offset);
188 			offset += 4;
189 			break;
190 		default:
191 			return -1;
192 		}
193 	}
194 
195 	return 0;
196 }
197 
198 /**
199  * Read values defined by a type string from a buffer, and write these values
200  * to environment variables.
201  *
202  * @param type_str	type string
203  * @param data		input buffer of values
204  * @param vars		names of environment variables
205  * Return: 0 on success, non-0 on error
206  */
207 int type_string_write_vars(const char *type_str, u8 *data,
208 			   char * const vars[])
209 {
210 	size_t offset;
211 	u32 value;
212 
213 	for (offset = 0; *type_str; type_str++, vars++) {
214 		switch (*type_str) {
215 		case 'b':
216 			value = data[offset];
217 			offset += 1;
218 			break;
219 		case 'w':
220 			value = get_unaligned_be16(data + offset);
221 			offset += 2;
222 			break;
223 		case 'd':
224 			value = get_unaligned_be32(data + offset);
225 			offset += 4;
226 			break;
227 		default:
228 			return -1;
229 		}
230 		if (env_set_ulong(*vars, value))
231 			return -1;
232 	}
233 
234 	return 0;
235 }
236 
237 static int tpm_show_device(void)
238 {
239 	struct udevice *dev;
240 	char buf[80];
241 	int n = 0, rc;
242 
243 	for_each_tpm_device(dev) {
244 		rc = tpm_get_desc(dev, buf, sizeof(buf));
245 		if (rc < 0)
246 			printf("device %d: can't get info\n", n);
247 		else
248 			printf("device %d: %s\n", n, buf);
249 
250 		n++;
251 	};
252 
253 	return 0;
254 }
255 
256 static int tpm_set_device(unsigned long num)
257 {
258 	struct udevice *dev;
259 	unsigned long n = 0;
260 	int rc = CMD_RET_FAILURE;
261 
262 	for_each_tpm_device(dev) {
263 		if (n == num) {
264 			rc = 0;
265 			break;
266 		}
267 
268 		n++;
269 	}
270 
271 	if (!rc)
272 		tpm_dev = dev;
273 
274 	return rc;
275 }
276 
277 int get_tpm(struct udevice **devp)
278 {
279 	int rc;
280 
281 	/*
282 	 * To keep a backward compatibility with previous code,
283 	 * if a tpm device is not explicitly set, we set the first one.
284 	 */
285 	if (!tpm_dev) {
286 		rc = tpm_set_device(0);
287 		if (rc) {
288 			printf("Couldn't set TPM 0 (rc = %d)\n", rc);
289 			return CMD_RET_FAILURE;
290 		}
291 	}
292 
293 	if (devp)
294 		*devp = tpm_dev;
295 
296 	return 0;
297 }
298 
299 int do_tpm_device(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
300 {
301 	unsigned long num;
302 	int rc;
303 
304 	if (argc == 2) {
305 		num = simple_strtoul(argv[1], NULL, 10);
306 
307 		rc = tpm_set_device(num);
308 		if (rc)
309 			printf("Couldn't set TPM %lu (rc = %d)\n", num, rc);
310 	} else {
311 		rc = tpm_show_device();
312 	}
313 
314 	return rc;
315 }
316 
317 int do_tpm_info(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
318 {
319 	struct udevice *dev;
320 	char buf[80];
321 	int rc;
322 
323 	rc = get_tpm(&dev);
324 	if (rc)
325 		return rc;
326 	rc = tpm_get_desc(dev, buf, sizeof(buf));
327 	if (rc < 0) {
328 		printf("Couldn't get TPM info (%d)\n", rc);
329 		return CMD_RET_FAILURE;
330 	}
331 	printf("%s\n", buf);
332 
333 	return 0;
334 }
335 
336 int do_tpm_report_state(cmd_tbl_t *cmdtp, int flag, int argc,
337 			char *const argv[])
338 {
339 	struct udevice *dev;
340 	char buf[80];
341 	int rc;
342 
343 	rc = get_tpm(&dev);
344 	if (rc)
345 		return rc;
346 	rc = tpm_report_state(dev, buf, sizeof(buf));
347 	if (rc < 0) {
348 		printf("Couldn't get TPM state (%d)\n", rc);
349 		return CMD_RET_FAILURE;
350 	}
351 	printf("%s\n", buf);
352 
353 	return 0;
354 }
355 
356 int do_tpm_init(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
357 {
358 	struct udevice *dev;
359 	int rc;
360 
361 	if (argc != 1)
362 		return CMD_RET_USAGE;
363 	rc = get_tpm(&dev);
364 	if (rc)
365 		return rc;
366 
367 	return report_return_code(tpm_init(dev));
368 }
369 
370 int do_tpm(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
371 {
372 	cmd_tbl_t *tpm_commands, *cmd;
373 	struct tpm_chip_priv *priv;
374 	struct udevice *dev;
375 	unsigned int size;
376 	int ret;
377 
378 	if (argc < 2)
379 		return CMD_RET_USAGE;
380 
381 	ret = get_tpm(&dev);
382 	if (ret)
383 		return ret;
384 
385 	priv = dev_get_uclass_priv(dev);
386 
387 	/* Below getters return NULL if the desired stack is not built */
388 	switch (priv->version) {
389 	case TPM_V1:
390 		tpm_commands = get_tpm1_commands(&size);
391 		break;
392 	case TPM_V2:
393 		tpm_commands = get_tpm2_commands(&size);
394 		break;
395 	default:
396 		tpm_commands = NULL;
397 	}
398 
399 	if (!tpm_commands)
400 		return CMD_RET_USAGE;
401 
402 	cmd = find_cmd_tbl(argv[1], tpm_commands, size);
403 	if (!cmd)
404 		return CMD_RET_USAGE;
405 
406 	return cmd->cmd(cmdtp, flag, argc - 1, argv + 1);
407 }
408