xref: /rk3399_rockchip-uboot/tools/env/fw_env.c (revision ff95e579cf53b9d621e0754ea869a703eec6cdd1)
1 /*
2  * (C) Copyright 2000-2010
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2008
6  * Guennadi Liakhovetski, DENX Software Engineering, lg@denx.de.
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #define _GNU_SOURCE
12 
13 #include <compiler.h>
14 #include <errno.h>
15 #include <env_flags.h>
16 #include <fcntl.h>
17 #include <linux/fs.h>
18 #include <linux/stringify.h>
19 #include <ctype.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <stddef.h>
23 #include <string.h>
24 #include <sys/types.h>
25 #include <sys/ioctl.h>
26 #include <sys/stat.h>
27 #include <unistd.h>
28 
29 #ifdef MTD_OLD
30 # include <stdint.h>
31 # include <linux/mtd/mtd.h>
32 #else
33 # define  __user	/* nothing */
34 # include <mtd/mtd-user.h>
35 #endif
36 
37 #include "fw_env.h"
38 
39 struct env_opts default_opts = {
40 #ifdef CONFIG_FILE
41 	.config_file = CONFIG_FILE
42 #endif
43 };
44 
45 #define DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
46 
47 #define min(x, y) ({				\
48 	typeof(x) _min1 = (x);			\
49 	typeof(y) _min2 = (y);			\
50 	(void) (&_min1 == &_min2);		\
51 	_min1 < _min2 ? _min1 : _min2; })
52 
53 struct envdev_s {
54 	const char *devname;		/* Device name */
55 	long long devoff;		/* Device offset */
56 	ulong env_size;			/* environment size */
57 	ulong erase_size;		/* device erase size */
58 	ulong env_sectors;		/* number of environment sectors */
59 	uint8_t mtd_type;		/* type of the MTD device */
60 };
61 
62 static struct envdev_s envdevices[2] =
63 {
64 	{
65 		.mtd_type = MTD_ABSENT,
66 	}, {
67 		.mtd_type = MTD_ABSENT,
68 	},
69 };
70 static int dev_current;
71 
72 #define DEVNAME(i)    envdevices[(i)].devname
73 #define DEVOFFSET(i)  envdevices[(i)].devoff
74 #define ENVSIZE(i)    envdevices[(i)].env_size
75 #define DEVESIZE(i)   envdevices[(i)].erase_size
76 #define ENVSECTORS(i) envdevices[(i)].env_sectors
77 #define DEVTYPE(i)    envdevices[(i)].mtd_type
78 
79 #define CUR_ENVSIZE ENVSIZE(dev_current)
80 
81 static unsigned long usable_envsize;
82 #define ENV_SIZE      usable_envsize
83 
84 struct env_image_single {
85 	uint32_t	crc;	/* CRC32 over data bytes    */
86 	char		data[];
87 };
88 
89 struct env_image_redundant {
90 	uint32_t	crc;	/* CRC32 over data bytes    */
91 	unsigned char	flags;	/* active or obsolete */
92 	char		data[];
93 };
94 
95 enum flag_scheme {
96 	FLAG_NONE,
97 	FLAG_BOOLEAN,
98 	FLAG_INCREMENTAL,
99 };
100 
101 struct environment {
102 	void			*image;
103 	uint32_t		*crc;
104 	unsigned char		*flags;
105 	char			*data;
106 	enum flag_scheme	flag_scheme;
107 };
108 
109 static struct environment environment = {
110 	.flag_scheme = FLAG_NONE,
111 };
112 
113 static int env_aes_cbc_crypt(char *data, const int enc, uint8_t *key);
114 
115 static int HaveRedundEnv = 0;
116 
117 static unsigned char active_flag = 1;
118 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
119 static unsigned char obsolete_flag = 0;
120 
121 #define DEFAULT_ENV_INSTANCE_STATIC
122 #include <env_default.h>
123 
124 static int flash_io (int mode);
125 static int parse_config(struct env_opts *opts);
126 
127 #if defined(CONFIG_FILE)
128 static int get_config (char *);
129 #endif
130 
131 static char *skip_chars(char *s)
132 {
133 	for (; *s != '\0'; s++) {
134 		if (isblank(*s))
135 			return s;
136 	}
137 	return NULL;
138 }
139 
140 static char *skip_blanks(char *s)
141 {
142 	for (; *s != '\0'; s++) {
143 		if (!isblank(*s))
144 			return s;
145 	}
146 	return NULL;
147 }
148 
149 /*
150  * s1 is either a simple 'name', or a 'name=value' pair.
151  * s2 is a 'name=value' pair.
152  * If the names match, return the value of s2, else NULL.
153  */
154 static char *envmatch(char *s1, char *s2)
155 {
156 	if (s1 == NULL || s2 == NULL)
157 		return NULL;
158 
159 	while (*s1 == *s2++)
160 		if (*s1++ == '=')
161 			return s2;
162 	if (*s1 == '\0' && *(s2 - 1) == '=')
163 		return s2;
164 	return NULL;
165 }
166 
167 /**
168  * Search the environment for a variable.
169  * Return the value, if found, or NULL, if not found.
170  */
171 char *fw_getenv (char *name)
172 {
173 	char *env, *nxt;
174 
175 	for (env = environment.data; *env; env = nxt + 1) {
176 		char *val;
177 
178 		for (nxt = env; *nxt; ++nxt) {
179 			if (nxt >= &environment.data[ENV_SIZE]) {
180 				fprintf (stderr, "## Error: "
181 					"environment not terminated\n");
182 				return NULL;
183 			}
184 		}
185 		val = envmatch (name, env);
186 		if (!val)
187 			continue;
188 		return val;
189 	}
190 	return NULL;
191 }
192 
193 /*
194  * Search the default environment for a variable.
195  * Return the value, if found, or NULL, if not found.
196  */
197 char *fw_getdefenv(char *name)
198 {
199 	char *env, *nxt;
200 
201 	for (env = default_environment; *env; env = nxt + 1) {
202 		char *val;
203 
204 		for (nxt = env; *nxt; ++nxt) {
205 			if (nxt >= &default_environment[ENV_SIZE]) {
206 				fprintf(stderr, "## Error: "
207 					"default environment not terminated\n");
208 				return NULL;
209 			}
210 		}
211 		val = envmatch(name, env);
212 		if (!val)
213 			continue;
214 		return val;
215 	}
216 	return NULL;
217 }
218 
219 int parse_aes_key(char *key, uint8_t *bin_key)
220 {
221 	char tmp[5] = { '0', 'x', 0, 0, 0 };
222 	unsigned long ul;
223 	int i;
224 
225 	if (strnlen(key, 64) != 32) {
226 		fprintf(stderr,
227 			"## Error: '-a' option requires 16-byte AES key\n");
228 		return -1;
229 	}
230 
231 	for (i = 0; i < 16; i++) {
232 		tmp[2] = key[0];
233 		tmp[3] = key[1];
234 		errno = 0;
235 		ul = strtoul(tmp, NULL, 16);
236 		if (errno) {
237 			fprintf(stderr,
238 				"## Error: '-a' option requires valid AES key\n");
239 			return -1;
240 		}
241 		bin_key[i] = ul & 0xff;
242 		key += 2;
243 	}
244 	return 0;
245 }
246 
247 /*
248  * Print the current definition of one, or more, or all
249  * environment variables
250  */
251 int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts)
252 {
253 	int i, rc = 0;
254 
255 	if (value_only && argc != 1) {
256 		fprintf(stderr,
257 			"## Error: `-n' option requires exactly one argument\n");
258 		return -1;
259 	}
260 
261 	if (!opts)
262 		opts = &default_opts;
263 
264 	if (fw_env_open(opts))
265 		return -1;
266 
267 	if (argc == 0) {		/* Print all env variables  */
268 		char *env, *nxt;
269 		for (env = environment.data; *env; env = nxt + 1) {
270 			for (nxt = env; *nxt; ++nxt) {
271 				if (nxt >= &environment.data[ENV_SIZE]) {
272 					fprintf (stderr, "## Error: "
273 						"environment not terminated\n");
274 					return -1;
275 				}
276 			}
277 
278 			printf ("%s\n", env);
279 		}
280 		return 0;
281 	}
282 
283 	for (i = 0; i < argc; ++i) {	/* print a subset of env variables */
284 		char *name = argv[i];
285 		char *val = NULL;
286 
287 		val = fw_getenv(name);
288 		if (!val) {
289 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
290 			rc = -1;
291 			continue;
292 		}
293 
294 		if (value_only) {
295 			puts(val);
296 			break;
297 		}
298 
299 		printf("%s=%s\n", name, val);
300 	}
301 
302 	return rc;
303 }
304 
305 int fw_env_close(struct env_opts *opts)
306 {
307 	int ret;
308 
309 	if (!opts)
310 		opts = &default_opts;
311 
312 	if (opts->aes_flag) {
313 		ret = env_aes_cbc_crypt(environment.data, 1,
314 					opts->aes_key);
315 		if (ret) {
316 			fprintf(stderr,
317 				"Error: can't encrypt env for flash\n");
318 			return ret;
319 		}
320 	}
321 
322 	/*
323 	 * Update CRC
324 	 */
325 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
326 
327 	/* write environment back to flash */
328 	if (flash_io(O_RDWR)) {
329 		fprintf(stderr,
330 			"Error: can't write fw_env to flash\n");
331 			return -1;
332 	}
333 
334 	return 0;
335 }
336 
337 
338 /*
339  * Set/Clear a single variable in the environment.
340  * This is called in sequence to update the environment
341  * in RAM without updating the copy in flash after each set
342  */
343 int fw_env_write(char *name, char *value)
344 {
345 	int len;
346 	char *env, *nxt;
347 	char *oldval = NULL;
348 	int deleting, creating, overwriting;
349 
350 	/*
351 	 * search if variable with this name already exists
352 	 */
353 	for (nxt = env = environment.data; *env; env = nxt + 1) {
354 		for (nxt = env; *nxt; ++nxt) {
355 			if (nxt >= &environment.data[ENV_SIZE]) {
356 				fprintf(stderr, "## Error: "
357 					"environment not terminated\n");
358 				errno = EINVAL;
359 				return -1;
360 			}
361 		}
362 		if ((oldval = envmatch (name, env)) != NULL)
363 			break;
364 	}
365 
366 	deleting = (oldval && !(value && strlen(value)));
367 	creating = (!oldval && (value && strlen(value)));
368 	overwriting = (oldval && (value && strlen(value)));
369 
370 	/* check for permission */
371 	if (deleting) {
372 		if (env_flags_validate_varaccess(name,
373 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
374 			printf("Can't delete \"%s\"\n", name);
375 			errno = EROFS;
376 			return -1;
377 		}
378 	} else if (overwriting) {
379 		if (env_flags_validate_varaccess(name,
380 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
381 			printf("Can't overwrite \"%s\"\n", name);
382 			errno = EROFS;
383 			return -1;
384 		} else if (env_flags_validate_varaccess(name,
385 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
386 			const char *defval = fw_getdefenv(name);
387 
388 			if (defval == NULL)
389 				defval = "";
390 			if (strcmp(oldval, defval)
391 			    != 0) {
392 				printf("Can't overwrite \"%s\"\n", name);
393 				errno = EROFS;
394 				return -1;
395 			}
396 		}
397 	} else if (creating) {
398 		if (env_flags_validate_varaccess(name,
399 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
400 			printf("Can't create \"%s\"\n", name);
401 			errno = EROFS;
402 			return -1;
403 		}
404 	} else
405 		/* Nothing to do */
406 		return 0;
407 
408 	if (deleting || overwriting) {
409 		if (*++nxt == '\0') {
410 			*env = '\0';
411 		} else {
412 			for (;;) {
413 				*env = *nxt++;
414 				if ((*env == '\0') && (*nxt == '\0'))
415 					break;
416 				++env;
417 			}
418 		}
419 		*++env = '\0';
420 	}
421 
422 	/* Delete only ? */
423 	if (!value || !strlen(value))
424 		return 0;
425 
426 	/*
427 	 * Append new definition at the end
428 	 */
429 	for (env = environment.data; *env || *(env + 1); ++env);
430 	if (env > environment.data)
431 		++env;
432 	/*
433 	 * Overflow when:
434 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
435 	 */
436 	len = strlen (name) + 2;
437 	/* add '=' for first arg, ' ' for all others */
438 	len += strlen(value) + 1;
439 
440 	if (len > (&environment.data[ENV_SIZE] - env)) {
441 		fprintf (stderr,
442 			"Error: environment overflow, \"%s\" deleted\n",
443 			name);
444 		return -1;
445 	}
446 
447 	while ((*env = *name++) != '\0')
448 		env++;
449 	*env = '=';
450 	while ((*++env = *value++) != '\0')
451 		;
452 
453 	/* end is marked with double '\0' */
454 	*++env = '\0';
455 
456 	return 0;
457 }
458 
459 /*
460  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
461  * 0	  - OK
462  * EINVAL - need at least 1 argument
463  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
464  *	    modified or deleted
465  *
466  */
467 int fw_setenv(int argc, char *argv[], struct env_opts *opts)
468 {
469 	int i;
470 	size_t len;
471 	char *name, **valv;
472 	char *value = NULL;
473 	int valc;
474 
475 	if (!opts)
476 		opts = &default_opts;
477 
478 	if (argc < 1) {
479 		fprintf(stderr, "## Error: variable name missing\n");
480 		errno = EINVAL;
481 		return -1;
482 	}
483 
484 	if (fw_env_open(opts)) {
485 		fprintf(stderr, "Error: environment not initialized\n");
486 		return -1;
487 	}
488 
489 	name = argv[0];
490 	valv = argv + 1;
491 	valc = argc - 1;
492 
493 	if (env_flags_validate_env_set_params(name, valv, valc) < 0)
494 		return -1;
495 
496 	len = 0;
497 	for (i = 0; i < valc; ++i) {
498 		char *val = valv[i];
499 		size_t val_len = strlen(val);
500 
501 		if (value)
502 			value[len - 1] = ' ';
503 		value = realloc(value, len + val_len + 1);
504 		if (!value) {
505 			fprintf(stderr,
506 				"Cannot malloc %zu bytes: %s\n",
507 				len, strerror(errno));
508 			return -1;
509 		}
510 
511 		memcpy(value + len, val, val_len);
512 		len += val_len;
513 		value[len++] = '\0';
514 	}
515 
516 	fw_env_write(name, value);
517 
518 	free(value);
519 
520 	return fw_env_close(opts);
521 }
522 
523 /*
524  * Parse  a file  and configure the u-boot variables.
525  * The script file has a very simple format, as follows:
526  *
527  * Each line has a couple with name, value:
528  * <white spaces>variable_name<white spaces>variable_value
529  *
530  * Both variable_name and variable_value are interpreted as strings.
531  * Any character after <white spaces> and before ending \r\n is interpreted
532  * as variable's value (no comment allowed on these lines !)
533  *
534  * Comments are allowed if the first character in the line is #
535  *
536  * Returns -1 and sets errno error codes:
537  * 0	  - OK
538  * -1     - Error
539  */
540 int fw_parse_script(char *fname, struct env_opts *opts)
541 {
542 	FILE *fp;
543 	char dump[1024];	/* Maximum line length in the file */
544 	char *name;
545 	char *val;
546 	int lineno = 0;
547 	int len;
548 	int ret = 0;
549 
550 	if (!opts)
551 		opts = &default_opts;
552 
553 	if (fw_env_open(opts)) {
554 		fprintf(stderr, "Error: environment not initialized\n");
555 		return -1;
556 	}
557 
558 	if (strcmp(fname, "-") == 0)
559 		fp = stdin;
560 	else {
561 		fp = fopen(fname, "r");
562 		if (fp == NULL) {
563 			fprintf(stderr, "I cannot open %s for reading\n",
564 				 fname);
565 			return -1;
566 		}
567 	}
568 
569 	while (fgets(dump, sizeof(dump), fp)) {
570 		lineno++;
571 		len = strlen(dump);
572 
573 		/*
574 		 * Read a whole line from the file. If the line is too long
575 		 * or is not terminated, reports an error and exit.
576 		 */
577 		if (dump[len - 1] != '\n') {
578 			fprintf(stderr,
579 			"Line %d not corrected terminated or too long\n",
580 				lineno);
581 			ret = -1;
582 			break;
583 		}
584 
585 		/* Drop ending line feed / carriage return */
586 		dump[--len] = '\0';
587 		if (len && dump[len - 1] == '\r')
588 			dump[--len] = '\0';
589 
590 		/* Skip comment or empty lines */
591 		if (len == 0 || dump[0] == '#')
592 			continue;
593 
594 		/*
595 		 * Search for variable's name,
596 		 * remove leading whitespaces
597 		 */
598 		name = skip_blanks(dump);
599 		if (!name)
600 			continue;
601 
602 		/* The first white space is the end of variable name */
603 		val = skip_chars(name);
604 		len = strlen(name);
605 		if (val) {
606 			*val++ = '\0';
607 			if ((val - name) < len)
608 				val = skip_blanks(val);
609 			else
610 				val = NULL;
611 		}
612 
613 #ifdef DEBUG
614 		fprintf(stderr, "Setting %s : %s\n",
615 			name, val ? val : " removed");
616 #endif
617 
618 		if (env_flags_validate_type(name, val) < 0) {
619 			ret = -1;
620 			break;
621 		}
622 
623 		/*
624 		 * If there is an error setting a variable,
625 		 * try to save the environment and returns an error
626 		 */
627 		if (fw_env_write(name, val)) {
628 			fprintf(stderr,
629 			"fw_env_write returns with error : %s\n",
630 				strerror(errno));
631 			ret = -1;
632 			break;
633 		}
634 
635 	}
636 
637 	/* Close file if not stdin */
638 	if (strcmp(fname, "-") != 0)
639 		fclose(fp);
640 
641 	ret |= fw_env_close(opts);
642 
643 	return ret;
644 }
645 
646 /**
647  * environment_end() - compute offset of first byte right after environemnt
648  * @dev - index of enviroment buffer
649  * Return:
650  *  device offset of first byte right after environemnt
651  */
652 off_t environment_end(int dev)
653 {
654 	/* environment is block aligned */
655 	return DEVOFFSET(dev) + ENVSECTORS(dev) * DEVESIZE(dev);
656 }
657 
658 /*
659  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
660  * 0	- block is good
661  * > 0	- block is bad
662  * < 0	- failed to test
663  */
664 static int flash_bad_block(int fd, uint8_t mtd_type, loff_t blockstart)
665 {
666 	if (mtd_type == MTD_NANDFLASH) {
667 		int badblock = ioctl(fd, MEMGETBADBLOCK, &blockstart);
668 
669 		if (badblock < 0) {
670 			perror ("Cannot read bad block mark");
671 			return badblock;
672 		}
673 
674 		if (badblock) {
675 #ifdef DEBUG
676 			fprintf (stderr, "Bad block at 0x%llx, skipping\n",
677 				(unsigned long long)blockstart);
678 #endif
679 			return badblock;
680 		}
681 	}
682 
683 	return 0;
684 }
685 
686 /*
687  * Read data from flash at an offset into a provided buffer. On NAND it skips
688  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
689  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
690  */
691 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
692 			   off_t offset)
693 {
694 	size_t blocklen;	/* erase / write length - one block on NAND,
695 				   0 on NOR */
696 	size_t processed = 0;	/* progress counter */
697 	size_t readlen = count;	/* current read length */
698 	off_t block_seek;	/* offset inside the current block to the start
699 				   of the data */
700 	loff_t blockstart;	/* running start of the current block -
701 				   MEMGETBADBLOCK needs 64 bits */
702 	int rc;
703 
704 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
705 
706 	/* Offset inside a block */
707 	block_seek = offset - blockstart;
708 
709 	if (DEVTYPE(dev) == MTD_NANDFLASH) {
710 		/*
711 		 * NAND: calculate which blocks we are reading. We have
712 		 * to read one block at a time to skip bad blocks.
713 		 */
714 		blocklen = DEVESIZE (dev);
715 
716 		/* Limit to one block for the first read */
717 		if (readlen > blocklen - block_seek)
718 			readlen = blocklen - block_seek;
719 	} else {
720 		blocklen = 0;
721 	}
722 
723 	/* This only runs once on NOR flash */
724 	while (processed < count) {
725 		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
726 		if (rc < 0)		/* block test failed */
727 			return -1;
728 
729 		if (blockstart + block_seek + readlen > environment_end(dev)) {
730 			/* End of range is reached */
731 			fprintf (stderr,
732 				 "Too few good blocks within range\n");
733 			return -1;
734 		}
735 
736 		if (rc) {		/* block is bad */
737 			blockstart += blocklen;
738 			continue;
739 		}
740 
741 		/*
742 		 * If a block is bad, we retry in the next block at the same
743 		 * offset - see common/env_nand.c::writeenv()
744 		 */
745 		lseek (fd, blockstart + block_seek, SEEK_SET);
746 
747 		rc = read (fd, buf + processed, readlen);
748 		if (rc != readlen) {
749 			fprintf (stderr, "Read error on %s: %s\n",
750 				 DEVNAME (dev), strerror (errno));
751 			return -1;
752 		}
753 #ifdef DEBUG
754 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
755 			rc, (unsigned long long) blockstart + block_seek,
756 			DEVNAME(dev));
757 #endif
758 		processed += readlen;
759 		readlen = min (blocklen, count - processed);
760 		block_seek = 0;
761 		blockstart += blocklen;
762 	}
763 
764 	return processed;
765 }
766 
767 /*
768  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
769  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
770  * erase and write the whole data at once.
771  */
772 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
773 			    off_t offset)
774 {
775 	void *data;
776 	struct erase_info_user erase;
777 	size_t blocklen;	/* length of NAND block / NOR erase sector */
778 	size_t erase_len;	/* whole area that can be erased - may include
779 				   bad blocks */
780 	size_t erasesize;	/* erase / write length - one block on NAND,
781 				   whole area on NOR */
782 	size_t processed = 0;	/* progress counter */
783 	size_t write_total;	/* total size to actually write - excluding
784 				   bad blocks */
785 	off_t erase_offset;	/* offset to the first erase block (aligned)
786 				   below offset */
787 	off_t block_seek;	/* offset inside the erase block to the start
788 				   of the data */
789 	loff_t blockstart;	/* running start of the current block -
790 				   MEMGETBADBLOCK needs 64 bits */
791 	int rc;
792 
793 	/*
794 	 * For mtd devices only offset and size of the environment do matter
795 	 */
796 	if (DEVTYPE(dev) == MTD_ABSENT) {
797 		blocklen = count;
798 		erase_len = blocklen;
799 		blockstart = offset;
800 		block_seek = 0;
801 		write_total = blocklen;
802 	} else {
803 		blocklen = DEVESIZE(dev);
804 
805 		erase_offset = (offset / blocklen) * blocklen;
806 
807 		/* Maximum area we may use */
808 		erase_len = environment_end(dev) - erase_offset;
809 
810 		blockstart = erase_offset;
811 		/* Offset inside a block */
812 		block_seek = offset - erase_offset;
813 
814 		/*
815 		 * Data size we actually write: from the start of the block
816 		 * to the start of the data, then count bytes of data, and
817 		 * to the end of the block
818 		 */
819 		write_total = ((block_seek + count + blocklen - 1) /
820 							blocklen) * blocklen;
821 	}
822 
823 	/*
824 	 * Support data anywhere within erase sectors: read out the complete
825 	 * area to be erased, replace the environment image, write the whole
826 	 * block back again.
827 	 */
828 	if (write_total > count) {
829 		data = malloc (erase_len);
830 		if (!data) {
831 			fprintf (stderr,
832 				 "Cannot malloc %zu bytes: %s\n",
833 				 erase_len, strerror (errno));
834 			return -1;
835 		}
836 
837 		rc = flash_read_buf(dev, fd, data, write_total, erase_offset);
838 		if (write_total != rc)
839 			return -1;
840 
841 #ifdef DEBUG
842 		fprintf(stderr, "Preserving data ");
843 		if (block_seek != 0)
844 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
845 		if (block_seek + count != write_total) {
846 			if (block_seek != 0)
847 				fprintf(stderr, " and ");
848 			fprintf(stderr, "0x%lx - 0x%lx",
849 				(unsigned long) block_seek + count,
850 				(unsigned long) write_total - 1);
851 		}
852 		fprintf(stderr, "\n");
853 #endif
854 		/* Overwrite the old environment */
855 		memcpy (data + block_seek, buf, count);
856 	} else {
857 		/*
858 		 * We get here, iff offset is block-aligned and count is a
859 		 * multiple of blocklen - see write_total calculation above
860 		 */
861 		data = buf;
862 	}
863 
864 	if (DEVTYPE(dev) == MTD_NANDFLASH) {
865 		/*
866 		 * NAND: calculate which blocks we are writing. We have
867 		 * to write one block at a time to skip bad blocks.
868 		 */
869 		erasesize = blocklen;
870 	} else {
871 		erasesize = erase_len;
872 	}
873 
874 	erase.length = erasesize;
875 
876 	/* This only runs once on NOR flash and SPI-dataflash */
877 	while (processed < write_total) {
878 		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
879 		if (rc < 0)		/* block test failed */
880 			return rc;
881 
882 		if (blockstart + erasesize > environment_end(dev)) {
883 			fprintf (stderr, "End of range reached, aborting\n");
884 			return -1;
885 		}
886 
887 		if (rc) {		/* block is bad */
888 			blockstart += blocklen;
889 			continue;
890 		}
891 
892 		if (DEVTYPE(dev) != MTD_ABSENT) {
893 			erase.start = blockstart;
894 			ioctl(fd, MEMUNLOCK, &erase);
895 			/* These do not need an explicit erase cycle */
896 			if (DEVTYPE(dev) != MTD_DATAFLASH)
897 				if (ioctl(fd, MEMERASE, &erase) != 0) {
898 					fprintf(stderr,
899 						"MTD erase error on %s: %s\n",
900 						DEVNAME(dev), strerror(errno));
901 					return -1;
902 				}
903 		}
904 
905 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
906 			fprintf (stderr,
907 				 "Seek error on %s: %s\n",
908 				 DEVNAME (dev), strerror (errno));
909 			return -1;
910 		}
911 
912 #ifdef DEBUG
913 		fprintf(stderr, "Write 0x%llx bytes at 0x%llx\n",
914 			(unsigned long long) erasesize,
915 			(unsigned long long) blockstart);
916 #endif
917 		if (write (fd, data + processed, erasesize) != erasesize) {
918 			fprintf (stderr, "Write error on %s: %s\n",
919 				 DEVNAME (dev), strerror (errno));
920 			return -1;
921 		}
922 
923 		if (DEVTYPE(dev) != MTD_ABSENT)
924 			ioctl(fd, MEMLOCK, &erase);
925 
926 		processed  += erasesize;
927 		block_seek = 0;
928 		blockstart += erasesize;
929 	}
930 
931 	if (write_total > count)
932 		free (data);
933 
934 	return processed;
935 }
936 
937 /*
938  * Set obsolete flag at offset - NOR flash only
939  */
940 static int flash_flag_obsolete (int dev, int fd, off_t offset)
941 {
942 	int rc;
943 	struct erase_info_user erase;
944 
945 	erase.start  = DEVOFFSET (dev);
946 	erase.length = DEVESIZE (dev);
947 	/* This relies on the fact, that obsolete_flag == 0 */
948 	rc = lseek (fd, offset, SEEK_SET);
949 	if (rc < 0) {
950 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
951 			 DEVNAME (dev));
952 		return rc;
953 	}
954 	ioctl (fd, MEMUNLOCK, &erase);
955 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
956 	ioctl (fd, MEMLOCK, &erase);
957 	if (rc < 0)
958 		perror ("Could not set obsolete flag");
959 
960 	return rc;
961 }
962 
963 /* Encrypt or decrypt the environment before writing or reading it. */
964 static int env_aes_cbc_crypt(char *payload, const int enc, uint8_t *key)
965 {
966 	uint8_t *data = (uint8_t *)payload;
967 	const int len = usable_envsize;
968 	uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
969 	uint32_t aes_blocks;
970 
971 	/* First we expand the key. */
972 	aes_expand_key(key, key_exp);
973 
974 	/* Calculate the number of AES blocks to encrypt. */
975 	aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
976 
977 	if (enc)
978 		aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
979 	else
980 		aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
981 
982 	return 0;
983 }
984 
985 static int flash_write (int fd_current, int fd_target, int dev_target)
986 {
987 	int rc;
988 
989 	switch (environment.flag_scheme) {
990 	case FLAG_NONE:
991 		break;
992 	case FLAG_INCREMENTAL:
993 		(*environment.flags)++;
994 		break;
995 	case FLAG_BOOLEAN:
996 		*environment.flags = active_flag;
997 		break;
998 	default:
999 		fprintf (stderr, "Unimplemented flash scheme %u \n",
1000 			 environment.flag_scheme);
1001 		return -1;
1002 	}
1003 
1004 #ifdef DEBUG
1005 	fprintf(stderr, "Writing new environment at 0x%llx on %s\n",
1006 		DEVOFFSET (dev_target), DEVNAME (dev_target));
1007 #endif
1008 
1009 	rc = flash_write_buf(dev_target, fd_target, environment.image,
1010 			     CUR_ENVSIZE, DEVOFFSET(dev_target));
1011 	if (rc < 0)
1012 		return rc;
1013 
1014 	if (environment.flag_scheme == FLAG_BOOLEAN) {
1015 		/* Have to set obsolete flag */
1016 		off_t offset = DEVOFFSET (dev_current) +
1017 			offsetof (struct env_image_redundant, flags);
1018 #ifdef DEBUG
1019 		fprintf(stderr,
1020 			"Setting obsolete flag in environment at 0x%llx on %s\n",
1021 			DEVOFFSET (dev_current), DEVNAME (dev_current));
1022 #endif
1023 		flash_flag_obsolete (dev_current, fd_current, offset);
1024 	}
1025 
1026 	return 0;
1027 }
1028 
1029 static int flash_read (int fd)
1030 {
1031 	int rc;
1032 
1033 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1034 			    DEVOFFSET(dev_current));
1035 	if (rc != CUR_ENVSIZE)
1036 		return -1;
1037 
1038 	return 0;
1039 }
1040 
1041 static int flash_io (int mode)
1042 {
1043 	int fd_current, fd_target, rc, dev_target;
1044 
1045 	/* dev_current: fd_current, erase_current */
1046 	fd_current = open (DEVNAME (dev_current), mode);
1047 	if (fd_current < 0) {
1048 		fprintf (stderr,
1049 			 "Can't open %s: %s\n",
1050 			 DEVNAME (dev_current), strerror (errno));
1051 		return -1;
1052 	}
1053 
1054 	if (mode == O_RDWR) {
1055 		if (HaveRedundEnv) {
1056 			/* switch to next partition for writing */
1057 			dev_target = !dev_current;
1058 			/* dev_target: fd_target, erase_target */
1059 			fd_target = open (DEVNAME (dev_target), mode);
1060 			if (fd_target < 0) {
1061 				fprintf (stderr,
1062 					 "Can't open %s: %s\n",
1063 					 DEVNAME (dev_target),
1064 					 strerror (errno));
1065 				rc = -1;
1066 				goto exit;
1067 			}
1068 		} else {
1069 			dev_target = dev_current;
1070 			fd_target = fd_current;
1071 		}
1072 
1073 		rc = flash_write (fd_current, fd_target, dev_target);
1074 
1075 		if (HaveRedundEnv) {
1076 			if (close (fd_target)) {
1077 				fprintf (stderr,
1078 					"I/O error on %s: %s\n",
1079 					DEVNAME (dev_target),
1080 					strerror (errno));
1081 				rc = -1;
1082 			}
1083 		}
1084 	} else {
1085 		rc = flash_read (fd_current);
1086 	}
1087 
1088 exit:
1089 	if (close (fd_current)) {
1090 		fprintf (stderr,
1091 			 "I/O error on %s: %s\n",
1092 			 DEVNAME (dev_current), strerror (errno));
1093 		return -1;
1094 	}
1095 
1096 	return rc;
1097 }
1098 
1099 /*
1100  * Prevent confusion if running from erased flash memory
1101  */
1102 int fw_env_open(struct env_opts *opts)
1103 {
1104 	int crc0, crc0_ok;
1105 	unsigned char flag0;
1106 	void *addr0;
1107 
1108 	int crc1, crc1_ok;
1109 	unsigned char flag1;
1110 	void *addr1;
1111 
1112 	int ret;
1113 
1114 	struct env_image_single *single;
1115 	struct env_image_redundant *redundant;
1116 
1117 	if (!opts)
1118 		opts = &default_opts;
1119 
1120 	if (parse_config(opts))		/* should fill envdevices */
1121 		return -1;
1122 
1123 	addr0 = calloc(1, CUR_ENVSIZE);
1124 	if (addr0 == NULL) {
1125 		fprintf(stderr,
1126 			"Not enough memory for environment (%ld bytes)\n",
1127 			CUR_ENVSIZE);
1128 		return -1;
1129 	}
1130 
1131 	/* read environment from FLASH to local buffer */
1132 	environment.image = addr0;
1133 
1134 	if (HaveRedundEnv) {
1135 		redundant = addr0;
1136 		environment.crc		= &redundant->crc;
1137 		environment.flags	= &redundant->flags;
1138 		environment.data	= redundant->data;
1139 	} else {
1140 		single = addr0;
1141 		environment.crc		= &single->crc;
1142 		environment.flags	= NULL;
1143 		environment.data	= single->data;
1144 	}
1145 
1146 	dev_current = 0;
1147 	if (flash_io (O_RDONLY))
1148 		return -1;
1149 
1150 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1151 
1152 	if (opts->aes_flag) {
1153 		ret = env_aes_cbc_crypt(environment.data, 0,
1154 					opts->aes_key);
1155 		if (ret)
1156 			return ret;
1157 	}
1158 
1159 	crc0_ok = (crc0 == *environment.crc);
1160 	if (!HaveRedundEnv) {
1161 		if (!crc0_ok) {
1162 			fprintf (stderr,
1163 				"Warning: Bad CRC, using default environment\n");
1164 			memcpy(environment.data, default_environment, sizeof default_environment);
1165 		}
1166 	} else {
1167 		flag0 = *environment.flags;
1168 
1169 		dev_current = 1;
1170 		addr1 = calloc(1, CUR_ENVSIZE);
1171 		if (addr1 == NULL) {
1172 			fprintf(stderr,
1173 				"Not enough memory for environment (%ld bytes)\n",
1174 				CUR_ENVSIZE);
1175 			return -1;
1176 		}
1177 		redundant = addr1;
1178 
1179 		/*
1180 		 * have to set environment.image for flash_read(), careful -
1181 		 * other pointers in environment still point inside addr0
1182 		 */
1183 		environment.image = addr1;
1184 		if (flash_io (O_RDONLY))
1185 			return -1;
1186 
1187 		/* Check flag scheme compatibility */
1188 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1189 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1190 			environment.flag_scheme = FLAG_BOOLEAN;
1191 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1192 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1193 			environment.flag_scheme = FLAG_INCREMENTAL;
1194 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1195 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1196 			environment.flag_scheme = FLAG_BOOLEAN;
1197 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1198 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1199 			environment.flag_scheme = FLAG_INCREMENTAL;
1200 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1201 			   DEVTYPE(!dev_current) == MTD_ABSENT) {
1202 			environment.flag_scheme = FLAG_INCREMENTAL;
1203 		} else {
1204 			fprintf (stderr, "Incompatible flash types!\n");
1205 			return -1;
1206 		}
1207 
1208 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1209 
1210 		if (opts->aes_flag) {
1211 			ret = env_aes_cbc_crypt(redundant->data, 0,
1212 						opts->aes_key);
1213 			if (ret)
1214 				return ret;
1215 		}
1216 
1217 		crc1_ok = (crc1 == redundant->crc);
1218 		flag1 = redundant->flags;
1219 
1220 		if (crc0_ok && !crc1_ok) {
1221 			dev_current = 0;
1222 		} else if (!crc0_ok && crc1_ok) {
1223 			dev_current = 1;
1224 		} else if (!crc0_ok && !crc1_ok) {
1225 			fprintf (stderr,
1226 				"Warning: Bad CRC, using default environment\n");
1227 			memcpy (environment.data, default_environment,
1228 				sizeof default_environment);
1229 			dev_current = 0;
1230 		} else {
1231 			switch (environment.flag_scheme) {
1232 			case FLAG_BOOLEAN:
1233 				if (flag0 == active_flag &&
1234 				    flag1 == obsolete_flag) {
1235 					dev_current = 0;
1236 				} else if (flag0 == obsolete_flag &&
1237 					   flag1 == active_flag) {
1238 					dev_current = 1;
1239 				} else if (flag0 == flag1) {
1240 					dev_current = 0;
1241 				} else if (flag0 == 0xFF) {
1242 					dev_current = 0;
1243 				} else if (flag1 == 0xFF) {
1244 					dev_current = 1;
1245 				} else {
1246 					dev_current = 0;
1247 				}
1248 				break;
1249 			case FLAG_INCREMENTAL:
1250 				if (flag0 == 255 && flag1 == 0)
1251 					dev_current = 1;
1252 				else if ((flag1 == 255 && flag0 == 0) ||
1253 					 flag0 >= flag1)
1254 					dev_current = 0;
1255 				else /* flag1 > flag0 */
1256 					dev_current = 1;
1257 				break;
1258 			default:
1259 				fprintf (stderr, "Unknown flag scheme %u \n",
1260 					 environment.flag_scheme);
1261 				return -1;
1262 			}
1263 		}
1264 
1265 		/*
1266 		 * If we are reading, we don't need the flag and the CRC any
1267 		 * more, if we are writing, we will re-calculate CRC and update
1268 		 * flags before writing out
1269 		 */
1270 		if (dev_current) {
1271 			environment.image	= addr1;
1272 			environment.crc		= &redundant->crc;
1273 			environment.flags	= &redundant->flags;
1274 			environment.data	= redundant->data;
1275 			free (addr0);
1276 		} else {
1277 			environment.image	= addr0;
1278 			/* Other pointers are already set */
1279 			free (addr1);
1280 		}
1281 #ifdef DEBUG
1282 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1283 #endif
1284 	}
1285 	return 0;
1286 }
1287 
1288 static int check_device_config(int dev)
1289 {
1290 	struct stat st;
1291 	int fd, rc = 0;
1292 
1293 	if (DEVOFFSET(dev) % DEVESIZE(dev) != 0) {
1294 		fprintf(stderr, "Environment does not start on (erase) block boundary\n");
1295 		errno = EINVAL;
1296 		return -1;
1297 	}
1298 
1299 	if (ENVSIZE(dev) > ENVSECTORS(dev) * DEVESIZE(dev)) {
1300 		fprintf(stderr, "Environment does not fit into available sectors\n");
1301 		errno = EINVAL;
1302 		return -1;
1303 	}
1304 
1305 	fd = open(DEVNAME(dev), O_RDONLY);
1306 	if (fd < 0) {
1307 		fprintf(stderr,
1308 			"Cannot open %s: %s\n",
1309 			DEVNAME(dev), strerror(errno));
1310 		return -1;
1311 	}
1312 
1313 	rc = fstat(fd, &st);
1314 	if (rc < 0) {
1315 		fprintf(stderr, "Cannot stat the file %s\n",
1316 			DEVNAME(dev));
1317 		goto err;
1318 	}
1319 
1320 	if (S_ISCHR(st.st_mode)) {
1321 		struct mtd_info_user mtdinfo;
1322 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1323 		if (rc < 0) {
1324 			fprintf(stderr, "Cannot get MTD information for %s\n",
1325 				DEVNAME(dev));
1326 			goto err;
1327 		}
1328 		if (mtdinfo.type != MTD_NORFLASH &&
1329 		    mtdinfo.type != MTD_NANDFLASH &&
1330 		    mtdinfo.type != MTD_DATAFLASH &&
1331 		    mtdinfo.type != MTD_UBIVOLUME) {
1332 			fprintf(stderr, "Unsupported flash type %u on %s\n",
1333 				mtdinfo.type, DEVNAME(dev));
1334 			goto err;
1335 		}
1336 		DEVTYPE(dev) = mtdinfo.type;
1337 	} else {
1338 		uint64_t size;
1339 		DEVTYPE(dev) = MTD_ABSENT;
1340 
1341 		/*
1342 		 * Check for negative offsets, treat it as backwards offset
1343 		 * from the end of the block device
1344 		 */
1345 		if (DEVOFFSET(dev) < 0) {
1346 			rc = ioctl(fd, BLKGETSIZE64, &size);
1347 			if (rc < 0) {
1348 				fprintf(stderr, "Could not get block device size on %s\n",
1349 					DEVNAME(dev));
1350 				goto err;
1351 			}
1352 
1353 			DEVOFFSET(dev) = DEVOFFSET(dev) + size;
1354 #ifdef DEBUG
1355 			fprintf(stderr, "Calculated device offset 0x%llx on %s\n",
1356 				DEVOFFSET(dev), DEVNAME(dev));
1357 #endif
1358 		}
1359 	}
1360 
1361 err:
1362 	close(fd);
1363 	return rc;
1364 }
1365 
1366 static int parse_config(struct env_opts *opts)
1367 {
1368 	int rc;
1369 
1370 	if (!opts)
1371 		opts = &default_opts;
1372 
1373 #if defined(CONFIG_FILE)
1374 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1375 	if (get_config(opts->config_file)) {
1376 		fprintf(stderr, "Cannot parse config file '%s': %m\n",
1377 			opts->config_file);
1378 		return -1;
1379 	}
1380 #else
1381 	DEVNAME (0) = DEVICE1_NAME;
1382 	DEVOFFSET (0) = DEVICE1_OFFSET;
1383 	ENVSIZE (0) = ENV1_SIZE;
1384 	/* Default values are: erase-size=env-size */
1385 	DEVESIZE (0) = ENVSIZE (0);
1386 	/* #sectors=env-size/erase-size (rounded up) */
1387 	ENVSECTORS (0) = (ENVSIZE(0) + DEVESIZE(0) - 1) / DEVESIZE(0);
1388 #ifdef DEVICE1_ESIZE
1389 	DEVESIZE (0) = DEVICE1_ESIZE;
1390 #endif
1391 #ifdef DEVICE1_ENVSECTORS
1392 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1393 #endif
1394 
1395 #ifdef HAVE_REDUND
1396 	DEVNAME (1) = DEVICE2_NAME;
1397 	DEVOFFSET (1) = DEVICE2_OFFSET;
1398 	ENVSIZE (1) = ENV2_SIZE;
1399 	/* Default values are: erase-size=env-size */
1400 	DEVESIZE (1) = ENVSIZE (1);
1401 	/* #sectors=env-size/erase-size (rounded up) */
1402 	ENVSECTORS (1) = (ENVSIZE(1) + DEVESIZE(1) - 1) / DEVESIZE(1);
1403 #ifdef DEVICE2_ESIZE
1404 	DEVESIZE (1) = DEVICE2_ESIZE;
1405 #endif
1406 #ifdef DEVICE2_ENVSECTORS
1407 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1408 #endif
1409 	HaveRedundEnv = 1;
1410 #endif
1411 #endif
1412 	rc = check_device_config(0);
1413 	if (rc < 0)
1414 		return rc;
1415 
1416 	if (HaveRedundEnv) {
1417 		rc = check_device_config(1);
1418 		if (rc < 0)
1419 			return rc;
1420 
1421 		if (ENVSIZE(0) != ENVSIZE(1)) {
1422 			fprintf(stderr,
1423 				"Redundant environments have unequal size");
1424 			return -1;
1425 		}
1426 	}
1427 
1428 	usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);
1429 	if (HaveRedundEnv)
1430 		usable_envsize -= sizeof(char);
1431 
1432 	if (opts->aes_flag)
1433 		usable_envsize &= ~(AES_KEY_LENGTH - 1);
1434 
1435 	return 0;
1436 }
1437 
1438 #if defined(CONFIG_FILE)
1439 static int get_config (char *fname)
1440 {
1441 	FILE *fp;
1442 	int i = 0;
1443 	int rc;
1444 	char dump[128];
1445 	char *devname;
1446 
1447 	fp = fopen (fname, "r");
1448 	if (fp == NULL)
1449 		return -1;
1450 
1451 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1452 		/* Skip incomplete conversions and comment strings */
1453 		if (dump[0] == '#')
1454 			continue;
1455 
1456 		rc = sscanf(dump, "%ms %lli %lx %lx %lx",
1457 			    &devname,
1458 			    &DEVOFFSET(i),
1459 			    &ENVSIZE(i),
1460 			    &DEVESIZE(i),
1461 			    &ENVSECTORS(i));
1462 
1463 		if (rc < 3)
1464 			continue;
1465 
1466 		DEVNAME(i) = devname;
1467 
1468 		if (rc < 4)
1469 			/* Assume the erase size is the same as the env-size */
1470 			DEVESIZE(i) = ENVSIZE(i);
1471 
1472 		if (rc < 5)
1473 			/* Assume enough env sectors to cover the environment */
1474 			ENVSECTORS (i) = (ENVSIZE(i) + DEVESIZE(i) - 1) / DEVESIZE(i);
1475 
1476 		i++;
1477 	}
1478 	fclose (fp);
1479 
1480 	HaveRedundEnv = i - 1;
1481 	if (!i) {			/* No valid entries found */
1482 		errno = EINVAL;
1483 		return -1;
1484 	} else
1485 		return 0;
1486 }
1487 #endif
1488