xref: /openbmc/u-boot/cmd/avb.c (revision 95963679)
1 
2 /*
3  * (C) Copyright 2018, Linaro Limited
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <avb_verify.h>
9 #include <command.h>
10 #include <image.h>
11 #include <malloc.h>
12 #include <mmc.h>
13 
14 #define AVB_BOOTARGS	"avb_bootargs"
15 static struct AvbOps *avb_ops;
16 
17 static const char * const requested_partitions[] = {"boot",
18 					     "system",
19 					     "vendor",
20 					     NULL};
21 
22 int do_avb_init(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
23 {
24 	unsigned long mmc_dev;
25 
26 	if (argc != 2)
27 		return CMD_RET_USAGE;
28 
29 	mmc_dev = simple_strtoul(argv[1], NULL, 16);
30 
31 	if (avb_ops)
32 		avb_ops_free(avb_ops);
33 
34 	avb_ops = avb_ops_alloc(mmc_dev);
35 	if (avb_ops)
36 		return CMD_RET_SUCCESS;
37 
38 	return CMD_RET_FAILURE;
39 }
40 
41 int do_avb_read_part(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
42 {
43 	const char *part;
44 	s64 offset;
45 	size_t bytes, bytes_read = 0;
46 	void *buffer;
47 
48 	if (!avb_ops) {
49 		printf("AVB 2.0 is not initialized, please run 'avb init'\n");
50 		return CMD_RET_USAGE;
51 	}
52 
53 	if (argc != 5)
54 		return CMD_RET_USAGE;
55 
56 	part = argv[1];
57 	offset = simple_strtoul(argv[2], NULL, 16);
58 	bytes = simple_strtoul(argv[3], NULL, 16);
59 	buffer = (void *)simple_strtoul(argv[4], NULL, 16);
60 
61 	if (avb_ops->read_from_partition(avb_ops, part, offset, bytes,
62 					 buffer, &bytes_read) ==
63 					 AVB_IO_RESULT_OK) {
64 		printf("Read %zu bytes\n", bytes_read);
65 		return CMD_RET_SUCCESS;
66 	}
67 
68 	return CMD_RET_FAILURE;
69 }
70 
71 int do_avb_read_part_hex(cmd_tbl_t *cmdtp, int flag, int argc,
72 			 char *const argv[])
73 {
74 	const char *part;
75 	s64 offset;
76 	size_t bytes, bytes_read = 0;
77 	char *buffer;
78 
79 	if (!avb_ops) {
80 		printf("AVB 2.0 is not initialized, please run 'avb init'\n");
81 		return CMD_RET_USAGE;
82 	}
83 
84 	if (argc != 4)
85 		return CMD_RET_USAGE;
86 
87 	part = argv[1];
88 	offset = simple_strtoul(argv[2], NULL, 16);
89 	bytes = simple_strtoul(argv[3], NULL, 16);
90 
91 	buffer = malloc(bytes);
92 	if (!buffer) {
93 		printf("Failed to tlb_allocate buffer for data\n");
94 		return CMD_RET_FAILURE;
95 	}
96 	memset(buffer, 0, bytes);
97 
98 	if (avb_ops->read_from_partition(avb_ops, part, offset, bytes, buffer,
99 					 &bytes_read) == AVB_IO_RESULT_OK) {
100 		printf("Requested %zu, read %zu bytes\n", bytes, bytes_read);
101 		printf("Data: ");
102 		for (int i = 0; i < bytes_read; i++)
103 			printf("%02X", buffer[i]);
104 
105 		printf("\n");
106 
107 		free(buffer);
108 		return CMD_RET_SUCCESS;
109 	}
110 
111 	free(buffer);
112 	return CMD_RET_FAILURE;
113 }
114 
115 int do_avb_write_part(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
116 {
117 	const char *part;
118 	s64 offset;
119 	size_t bytes;
120 	void *buffer;
121 
122 	if (!avb_ops) {
123 		printf("AVB 2.0 is not initialized, run 'avb init' first\n");
124 		return CMD_RET_FAILURE;
125 	}
126 
127 	if (argc != 5)
128 		return CMD_RET_USAGE;
129 
130 	part = argv[1];
131 	offset = simple_strtoul(argv[2], NULL, 16);
132 	bytes = simple_strtoul(argv[3], NULL, 16);
133 	buffer = (void *)simple_strtoul(argv[4], NULL, 16);
134 
135 	if (avb_ops->write_to_partition(avb_ops, part, offset, bytes, buffer) ==
136 	    AVB_IO_RESULT_OK) {
137 		printf("Wrote %zu bytes\n", bytes);
138 		return CMD_RET_SUCCESS;
139 	}
140 
141 	return CMD_RET_FAILURE;
142 }
143 
144 int do_avb_read_rb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
145 {
146 	size_t index;
147 	u64 rb_idx;
148 
149 	if (!avb_ops) {
150 		printf("AVB 2.0 is not initialized, run 'avb init' first\n");
151 		return CMD_RET_FAILURE;
152 	}
153 
154 	if (argc != 2)
155 		return CMD_RET_USAGE;
156 
157 	index = (size_t)simple_strtoul(argv[1], NULL, 16);
158 
159 	if (avb_ops->read_rollback_index(avb_ops, index, &rb_idx) ==
160 	    AVB_IO_RESULT_OK) {
161 		printf("Rollback index: %llu\n", rb_idx);
162 		return CMD_RET_SUCCESS;
163 	}
164 	return CMD_RET_FAILURE;
165 }
166 
167 int do_avb_write_rb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
168 {
169 	size_t index;
170 	u64 rb_idx;
171 
172 	if (!avb_ops) {
173 		printf("AVB 2.0 is not initialized, run 'avb init' first\n");
174 		return CMD_RET_FAILURE;
175 	}
176 
177 	if (argc != 3)
178 		return CMD_RET_USAGE;
179 
180 	index = (size_t)simple_strtoul(argv[1], NULL, 16);
181 	rb_idx = simple_strtoul(argv[2], NULL, 16);
182 
183 	if (avb_ops->write_rollback_index(avb_ops, index, rb_idx) ==
184 	    AVB_IO_RESULT_OK)
185 		return CMD_RET_SUCCESS;
186 
187 	return CMD_RET_FAILURE;
188 }
189 
190 int do_avb_get_uuid(cmd_tbl_t *cmdtp, int flag,
191 		    int argc, char * const argv[])
192 {
193 	const char *part;
194 	char buffer[UUID_STR_LEN + 1];
195 
196 	if (!avb_ops) {
197 		printf("AVB 2.0 is not initialized, run 'avb init' first\n");
198 		return CMD_RET_FAILURE;
199 	}
200 
201 	if (argc != 2)
202 		return CMD_RET_USAGE;
203 
204 	part = argv[1];
205 
206 	if (avb_ops->get_unique_guid_for_partition(avb_ops, part, buffer,
207 						   UUID_STR_LEN + 1) ==
208 						   AVB_IO_RESULT_OK) {
209 		printf("'%s' UUID: %s\n", part, buffer);
210 		return CMD_RET_SUCCESS;
211 	}
212 
213 	return CMD_RET_FAILURE;
214 }
215 
216 int do_avb_verify_part(cmd_tbl_t *cmdtp, int flag,
217 		       int argc, char *const argv[])
218 {
219 	AvbSlotVerifyResult slot_result;
220 	AvbSlotVerifyData *out_data;
221 	char *cmdline;
222 	char *extra_args;
223 
224 	bool unlocked = false;
225 	int res = CMD_RET_FAILURE;
226 
227 	if (!avb_ops) {
228 		printf("AVB 2.0 is not initialized, run 'avb init' first\n");
229 		return CMD_RET_FAILURE;
230 	}
231 
232 	if (argc != 1)
233 		return CMD_RET_USAGE;
234 
235 	printf("## Android Verified Boot 2.0 version %s\n",
236 	       avb_version_string());
237 
238 	if (avb_ops->read_is_device_unlocked(avb_ops, &unlocked) !=
239 	    AVB_IO_RESULT_OK) {
240 		printf("Can't determine device lock state.\n");
241 		return CMD_RET_FAILURE;
242 	}
243 
244 	slot_result =
245 		avb_slot_verify(avb_ops,
246 				requested_partitions,
247 				"",
248 				unlocked,
249 				AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
250 				&out_data);
251 
252 	switch (slot_result) {
253 	case AVB_SLOT_VERIFY_RESULT_OK:
254 		/* Until we don't have support of changing unlock states, we
255 		 * assume that we are by default in locked state.
256 		 * So in this case we can boot only when verification is
257 		 * successful; we also supply in cmdline GREEN boot state
258 		 */
259 		printf("Verification passed successfully\n");
260 
261 		/* export additional bootargs to AVB_BOOTARGS env var */
262 
263 		extra_args = avb_set_state(avb_ops, AVB_GREEN);
264 		if (extra_args)
265 			cmdline = append_cmd_line(out_data->cmdline,
266 						  extra_args);
267 		else
268 			cmdline = out_data->cmdline;
269 
270 		env_set(AVB_BOOTARGS, cmdline);
271 
272 		res = CMD_RET_SUCCESS;
273 		break;
274 	case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION:
275 		printf("Verification failed\n");
276 		break;
277 	case AVB_SLOT_VERIFY_RESULT_ERROR_IO:
278 		printf("I/O error occurred during verification\n");
279 		break;
280 	case AVB_SLOT_VERIFY_RESULT_ERROR_OOM:
281 		printf("OOM error occurred during verification\n");
282 		break;
283 	case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA:
284 		printf("Corrupted dm-verity metadata detected\n");
285 		break;
286 	case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION:
287 		printf("Unsupported version avbtool was used\n");
288 		break;
289 	case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX:
290 		printf("Checking rollback index failed\n");
291 		break;
292 	case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED:
293 		printf("Public key was rejected\n");
294 		break;
295 	default:
296 		printf("Unknown error occurred\n");
297 	}
298 
299 	return res;
300 }
301 
302 int do_avb_is_unlocked(cmd_tbl_t *cmdtp, int flag,
303 		       int argc, char * const argv[])
304 {
305 	bool unlock;
306 
307 	if (!avb_ops) {
308 		printf("AVB not initialized, run 'avb init' first\n");
309 		return CMD_RET_FAILURE;
310 	}
311 
312 	if (argc != 1) {
313 		printf("--%s(-1)\n", __func__);
314 		return CMD_RET_USAGE;
315 	}
316 
317 	if (avb_ops->read_is_device_unlocked(avb_ops, &unlock) ==
318 	    AVB_IO_RESULT_OK) {
319 		printf("Unlocked = %d\n", unlock);
320 		return CMD_RET_SUCCESS;
321 	}
322 
323 	return CMD_RET_FAILURE;
324 }
325 
326 static cmd_tbl_t cmd_avb[] = {
327 	U_BOOT_CMD_MKENT(init, 2, 0, do_avb_init, "", ""),
328 	U_BOOT_CMD_MKENT(read_rb, 2, 0, do_avb_read_rb, "", ""),
329 	U_BOOT_CMD_MKENT(write_rb, 3, 0, do_avb_write_rb, "", ""),
330 	U_BOOT_CMD_MKENT(is_unlocked, 1, 0, do_avb_is_unlocked, "", ""),
331 	U_BOOT_CMD_MKENT(get_uuid, 2, 0, do_avb_get_uuid, "", ""),
332 	U_BOOT_CMD_MKENT(read_part, 5, 0, do_avb_read_part, "", ""),
333 	U_BOOT_CMD_MKENT(read_part_hex, 4, 0, do_avb_read_part_hex, "", ""),
334 	U_BOOT_CMD_MKENT(write_part, 5, 0, do_avb_write_part, "", ""),
335 	U_BOOT_CMD_MKENT(verify, 1, 0, do_avb_verify_part, "", ""),
336 };
337 
338 static int do_avb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
339 {
340 	cmd_tbl_t *cp;
341 
342 	cp = find_cmd_tbl(argv[1], cmd_avb, ARRAY_SIZE(cmd_avb));
343 
344 	argc--;
345 	argv++;
346 
347 	if (!cp || argc > cp->maxargs)
348 		return CMD_RET_USAGE;
349 
350 	if (flag == CMD_FLAG_REPEAT)
351 		return CMD_RET_FAILURE;
352 
353 	return cp->cmd(cmdtp, flag, argc, argv);
354 }
355 
356 U_BOOT_CMD(
357 	avb, 29, 0, do_avb,
358 	"Provides commands for testing Android Verified Boot 2.0 functionality",
359 	"init <dev> - initialize avb2 for <dev>\n"
360 	"avb read_rb <num> - read rollback index at location <num>\n"
361 	"avb write_rb <num> <rb> - write rollback index <rb> to <num>\n"
362 	"avb is_unlocked - returns unlock status of the device\n"
363 	"avb get_uuid <partname> - read and print uuid of partition <part>\n"
364 	"avb read_part <partname> <offset> <num> <addr> - read <num> bytes from\n"
365 	"    partition <partname> to buffer <addr>\n"
366 	"avb read_part_hex <partname> <offset> <num> - read <num> bytes from\n"
367 	"    partition <partname> and print to stdout\n"
368 	"avb write_part <partname> <offset> <num> <addr> - write <num> bytes to\n"
369 	"    <partname> by <offset> using data from <addr>\n"
370 	"avb verify - run verification process using hash data\n"
371 	"    from vbmeta structure\n"
372 	);
373