1// SPDX-License-Identifier: GPL-2.0+
2/*
3 *  Integrate UEFI variables to u-boot env interface
4 *
5 *  Copyright (c) 2018 AKASHI Takahiro, Linaro Limited
6 */
7
8#include <charset.h>
9#include <common.h>
10#include <command.h>
11#include <efi_loader.h>
12#include <efi_variable.h>
13#include <env.h>
14#include <exports.h>
15#include <hexdump.h>
16#include <malloc.h>
17#include <mapmem.h>
18#include <rtc.h>
19#include <uuid.h>
20#include <linux/kernel.h>
21
22/*
23 * From efi_variable.c,
24 *
25 * Mapping between UEFI variables and u-boot variables:
26 *
27 *   efi_$guid_$varname = {attributes}(type)value
28 */
29
30static const struct {
31	u32 mask;
32	char *text;
33} efi_var_attrs[] = {
34	{EFI_VARIABLE_NON_VOLATILE, "NV"},
35	{EFI_VARIABLE_BOOTSERVICE_ACCESS, "BS"},
36	{EFI_VARIABLE_RUNTIME_ACCESS, "RT"},
37	{EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS, "AW"},
38	{EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS, "AT"},
39	{EFI_VARIABLE_READ_ONLY, "RO"},
40};
41
42/**
43 * efi_dump_single_var() - show information about a UEFI variable
44 *
45 * @name:	Name of the variable
46 * @guid:	Vendor GUID
47 * @verbose:	if true, dump data
48 *
49 * Show information encoded in one UEFI variable
50 */
51static void efi_dump_single_var(u16 *name, const efi_guid_t *guid, bool verbose)
52{
53	u32 attributes;
54	u8 *data;
55	u64 time;
56	struct rtc_time tm;
57	efi_uintn_t size;
58	int count, i;
59	efi_status_t ret;
60
61	data = NULL;
62	size = 0;
63	ret = efi_get_variable_int(name, guid, &attributes, &size, data, &time);
64	if (ret == EFI_BUFFER_TOO_SMALL) {
65		data = malloc(size);
66		if (!data)
67			goto out;
68
69		ret = efi_get_variable_int(name, guid, &attributes, &size,
70					   data, &time);
71	}
72	if (ret == EFI_NOT_FOUND) {
73		printf("Error: \"%ls\" not defined\n", name);
74		goto out;
75	}
76	if (ret != EFI_SUCCESS)
77		goto out;
78
79	rtc_to_tm(time, &tm);
80	printf("%ls:\n    %pUl (%pUs)\n", name, guid, guid);
81	if (attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
82		printf("    %04d-%02d-%02d %02d:%02d:%02d\n", tm.tm_year,
83		       tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
84	printf("    ");
85	for (count = 0, i = 0; i < ARRAY_SIZE(efi_var_attrs); i++)
86		if (attributes & efi_var_attrs[i].mask) {
87			if (count)
88				putc('|');
89			count++;
90			puts(efi_var_attrs[i].text);
91		}
92	printf(", DataSize = 0x%zx\n", size);
93	if (verbose)
94		print_hex_dump("    ", DUMP_PREFIX_OFFSET, 16, 1,
95			       data, size, true);
96
97out:
98	free(data);
99}
100
101static bool match_name(int argc, char *const argv[], u16 *var_name16)
102{
103	char *buf, *p;
104	size_t buflen;
105	int i;
106	bool result = false;
107
108	buflen = utf16_utf8_strlen(var_name16) + 1;
109	buf = calloc(1, buflen);
110	if (!buf)
111		return result;
112
113	p = buf;
114	utf16_utf8_strcpy(&p, var_name16);
115
116	for (i = 0; i < argc; argc--, argv++) {
117		if (!strcmp(buf, argv[i])) {
118			result = true;
119			goto out;
120		}
121	}
122
123out:
124	free(buf);
125
126	return result;
127}
128
129/**
130 * efi_dump_var_all() - show information about all the UEFI variables
131 *
132 * @argc:	Number of arguments (variables)
133 * @argv:	Argument (variable name) array
134 * @verbose:	if true, dump data
135 * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
136 *
137 * Show information encoded in all the UEFI variables
138 */
139static int efi_dump_var_all(int argc,  char *const argv[],
140			    const efi_guid_t *guid_p, bool verbose)
141{
142	u16 *var_name16, *p;
143	efi_uintn_t buf_size, size;
144	efi_guid_t guid;
145	efi_status_t ret;
146	bool match = false;
147
148	buf_size = 128;
149	var_name16 = malloc(buf_size);
150	if (!var_name16)
151		return CMD_RET_FAILURE;
152
153	var_name16[0] = 0;
154	for (;;) {
155		size = buf_size;
156		ret = efi_get_next_variable_name_int(&size, var_name16,
157						     &guid);
158		if (ret == EFI_NOT_FOUND)
159			break;
160		if (ret == EFI_BUFFER_TOO_SMALL) {
161			buf_size = size;
162			p = realloc(var_name16, buf_size);
163			if (!p) {
164				free(var_name16);
165				return CMD_RET_FAILURE;
166			}
167			var_name16 = p;
168			ret = efi_get_next_variable_name_int(&size, var_name16,
169							     &guid);
170		}
171		if (ret != EFI_SUCCESS) {
172			free(var_name16);
173			return CMD_RET_FAILURE;
174		}
175
176		if (guid_p && guidcmp(guid_p, &guid))
177			continue;
178		if (!argc || match_name(argc, argv, var_name16)) {
179			match = true;
180			efi_dump_single_var(var_name16, &guid, verbose);
181		}
182	}
183	free(var_name16);
184
185	if (!match && argc == 1) {
186		printf("Error: \"%s\" not defined\n", argv[0]);
187		return CMD_RET_FAILURE;
188	}
189
190	return CMD_RET_SUCCESS;
191}
192
193/**
194 * do_env_print_efi() - show information about UEFI variables
195 *
196 * @cmdtp:	Command table
197 * @flag:	Command flag
198 * @argc:	Number of arguments
199 * @argv:	Argument array
200 * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
201 *
202 * This function is for "env print -e" or "printenv -e" command:
203 *   => env print -e [-n] [-guid <guid> | -all] [var [...]]
204 * If one or more variable names are specified, show information
205 * named UEFI variables, otherwise show all the UEFI variables.
206 */
207int do_env_print_efi(struct cmd_tbl *cmdtp, int flag, int argc,
208		     char *const argv[])
209{
210	const efi_guid_t *guid_p = NULL;
211	efi_guid_t guid;
212	bool verbose = true;
213	efi_status_t ret;
214
215	/* Initialize EFI drivers */
216	ret = efi_init_obj_list();
217	if (ret != EFI_SUCCESS) {
218		printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
219		       ret & ~EFI_ERROR_MASK);
220		return CMD_RET_FAILURE;
221	}
222
223	for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
224		if (!strcmp(argv[0], "-guid")) {
225			if (argc == 1)
226				return CMD_RET_USAGE;
227			argc--;
228			argv++;
229			if (uuid_str_to_bin(argv[0], guid.b,
230					    UUID_STR_FORMAT_GUID))
231				return CMD_RET_USAGE;
232			guid_p = (const efi_guid_t *)guid.b;
233		} else if (!strcmp(argv[0], "-n")) {
234			verbose = false;
235		} else {
236			return CMD_RET_USAGE;
237		}
238	}
239
240	/* enumerate and show all UEFI variables */
241	return efi_dump_var_all(argc, argv, guid_p, verbose);
242}
243
244/**
245 * append_value() - encode UEFI variable's value
246 * @bufp:	Buffer of encoded UEFI variable's value
247 * @sizep:	Size of buffer
248 * @data:	data to be encoded into the value
249 * Return:	0 on success, -1 otherwise
250 *
251 * Interpret a given data string and append it to buffer.
252 * Buffer will be realloc'ed if necessary.
253 *
254 * Currently supported formats are:
255 *   =0x0123...:		Hexadecimal number
256 *   =H0123...:			Hexadecimal-byte array
257 *   ="...", =S"..." or <string>:
258 *				String
259 */
260static int append_value(char **bufp, size_t *sizep, char *data)
261{
262	char *tmp_buf = NULL, *new_buf = NULL, *value;
263	unsigned long len = 0;
264
265	if (!strncmp(data, "=0x", 3)) { /* hexadecimal number */
266		union {
267			u8 u8;
268			u16 u16;
269			u32 u32;
270			u64 u64;
271		} tmp_data;
272		unsigned long hex_value;
273		void *hex_ptr;
274
275		data += 3;
276		len = strlen(data);
277		if ((len & 0x1)) /* not multiple of two */
278			return -1;
279
280		len /= 2;
281		if (len > 8)
282			return -1;
283		else if (len > 4)
284			len = 8;
285		else if (len > 2)
286			len = 4;
287
288		/* convert hex hexadecimal number */
289		if (strict_strtoul(data, 16, &hex_value) < 0)
290			return -1;
291
292		tmp_buf = malloc(len);
293		if (!tmp_buf)
294			return -1;
295
296		if (len == 1) {
297			tmp_data.u8 = hex_value;
298			hex_ptr = &tmp_data.u8;
299		} else if (len == 2) {
300			tmp_data.u16 = hex_value;
301			hex_ptr = &tmp_data.u16;
302		} else if (len == 4) {
303			tmp_data.u32 = hex_value;
304			hex_ptr = &tmp_data.u32;
305		} else {
306			tmp_data.u64 = hex_value;
307			hex_ptr = &tmp_data.u64;
308		}
309		memcpy(tmp_buf, hex_ptr, len);
310		value = tmp_buf;
311
312	} else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */
313		data += 2;
314		len = strlen(data);
315		if (len & 0x1) /* not multiple of two */
316			return -1;
317
318		len /= 2;
319		tmp_buf = malloc(len);
320		if (!tmp_buf)
321			return -1;
322
323		if (hex2bin((u8 *)tmp_buf, data, len) < 0) {
324			printf("Error: illegal hexadecimal string\n");
325			free(tmp_buf);
326			return -1;
327		}
328
329		value = tmp_buf;
330	} else { /* string */
331		if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) {
332			if (data[1] == '"')
333				data += 2;
334			else
335				data += 3;
336			value = data;
337			len = strlen(data) - 1;
338			if (data[len] != '"')
339				return -1;
340		} else {
341			value = data;
342			len = strlen(data);
343		}
344	}
345
346	new_buf = realloc(*bufp, *sizep + len);
347	if (!new_buf)
348		goto out;
349
350	memcpy(new_buf + *sizep, value, len);
351	*bufp = new_buf;
352	*sizep += len;
353
354out:
355	free(tmp_buf);
356
357	return 0;
358}
359
360/**
361 * do_env_set_efi() - set UEFI variable
362 *
363 * @cmdtp:	Command table
364 * @flag:	Command flag
365 * @argc:	Number of arguments
366 * @argv:	Argument array
367 * Return:	CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
368 *
369 * This function is for "env set -e" or "setenv -e" command:
370 *   => env set -e [-guid guid][-nv][-bs][-rt][-at][-a][-v]
371 *		   [-i address,size] var, or
372 *                 var [value ...]
373 * Encode values specified and set given UEFI variable.
374 * If no value is specified, delete the variable.
375 */
376int do_env_set_efi(struct cmd_tbl *cmdtp, int flag, int argc,
377		   char *const argv[])
378{
379	char *var_name, *value, *ep;
380	ulong addr;
381	efi_uintn_t size;
382	efi_guid_t guid;
383	u32 attributes;
384	bool default_guid, verbose, value_on_memory;
385	u16 *var_name16;
386	efi_status_t ret;
387
388	if (argc == 1)
389		return CMD_RET_USAGE;
390
391	/* Initialize EFI drivers */
392	ret = efi_init_obj_list();
393	if (ret != EFI_SUCCESS) {
394		printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
395		       ret & ~EFI_ERROR_MASK);
396		return CMD_RET_FAILURE;
397	}
398
399	/*
400	 * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
401	 *	     EFI_VARIABLE_RUNTIME_ACCESS;
402	 */
403	value = NULL;
404	size = 0;
405	attributes = 0;
406	guid = efi_global_variable_guid;
407	default_guid = true;
408	verbose = false;
409	value_on_memory = false;
410	for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
411		if (!strcmp(argv[0], "-guid")) {
412			if (argc == 1)
413				return CMD_RET_USAGE;
414
415			argc--;
416			argv++;
417			if (uuid_str_to_bin(argv[0], guid.b,
418					    UUID_STR_FORMAT_GUID)) {
419				return CMD_RET_USAGE;
420			}
421			default_guid = false;
422		} else if (!strcmp(argv[0], "-bs")) {
423			attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
424		} else if (!strcmp(argv[0], "-rt")) {
425			attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
426		} else if (!strcmp(argv[0], "-nv")) {
427			attributes |= EFI_VARIABLE_NON_VOLATILE;
428		} else if (!strcmp(argv[0], "-at")) {
429			attributes |=
430			  EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
431		} else if (!strcmp(argv[0], "-a")) {
432			attributes |= EFI_VARIABLE_APPEND_WRITE;
433		} else if (!strcmp(argv[0], "-i")) {
434			/* data comes from memory */
435			if (argc == 1)
436				return CMD_RET_USAGE;
437
438			argc--;
439			argv++;
440			addr = hextoul(argv[0], &ep);
441			if (*ep != ':')
442				return CMD_RET_USAGE;
443
444			/* 0 should be allowed for delete */
445			size = hextoul(++ep, NULL);
446
447			value_on_memory = true;
448		} else if (!strcmp(argv[0], "-v")) {
449			verbose = true;
450		} else {
451			return CMD_RET_USAGE;
452		}
453	}
454	if (!argc)
455		return CMD_RET_USAGE;
456
457	var_name = argv[0];
458	if (default_guid) {
459		if (!strcmp(var_name, "db") || !strcmp(var_name, "dbx") ||
460		    !strcmp(var_name, "dbt"))
461			guid = efi_guid_image_security_database;
462		else
463			guid = efi_global_variable_guid;
464	}
465
466	if (verbose) {
467		printf("GUID: %pUl (%pUs)\n", &guid, &guid);
468		printf("Attributes: 0x%x\n", attributes);
469	}
470
471	/* for value */
472	if (value_on_memory)
473		value = map_sysmem(addr, 0);
474	else if (argc > 1)
475		for (argc--, argv++; argc > 0; argc--, argv++)
476			if (append_value(&value, &size, argv[0]) < 0) {
477				printf("## Failed to process an argument, %s\n",
478				       argv[0]);
479				ret = CMD_RET_FAILURE;
480				goto out;
481			}
482
483	if (size && verbose) {
484		printf("Value:\n");
485		print_hex_dump("    ", DUMP_PREFIX_OFFSET,
486			       16, 1, value, size, true);
487	}
488
489	var_name16 = efi_convert_string(var_name);
490	if (!var_name16) {
491		printf("## Out of memory\n");
492		ret = CMD_RET_FAILURE;
493		goto out;
494	}
495	ret = efi_set_variable_int(var_name16, &guid, attributes, size, value,
496				   true);
497	free(var_name16);
498	unmap_sysmem(value);
499	if (ret == EFI_SUCCESS) {
500		ret = CMD_RET_SUCCESS;
501	} else {
502		const char *msg;
503
504		switch (ret) {
505		case EFI_NOT_FOUND:
506			msg = " (not found)";
507			break;
508		case EFI_WRITE_PROTECTED:
509			msg = " (read only)";
510			break;
511		case EFI_INVALID_PARAMETER:
512			msg = " (invalid parameter)";
513			break;
514		case EFI_SECURITY_VIOLATION:
515			msg = " (validation failed)";
516			break;
517		case EFI_OUT_OF_RESOURCES:
518			msg = " (out of memory)";
519			break;
520		default:
521			msg = "";
522			break;
523		}
524		printf("## Failed to set EFI variable%s\n", msg);
525		ret = CMD_RET_FAILURE;
526	}
527out:
528	if (value_on_memory)
529		unmap_sysmem(value);
530	else
531		free(value);
532
533	return ret;
534}
535