xref: /openbmc/u-boot/tools/env/fw_env.c (revision 4611d5ba)
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 #include <errno.h>
12 #include <env_flags.h>
13 #include <fcntl.h>
14 #include <linux/stringify.h>
15 #include <stdio.h>
16 #include <stdlib.h>
17 #include <stddef.h>
18 #include <string.h>
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 #include <sys/stat.h>
22 #include <unistd.h>
23 
24 #ifdef MTD_OLD
25 # include <stdint.h>
26 # include <linux/mtd/mtd.h>
27 #else
28 # define  __user	/* nothing */
29 # include <mtd/mtd-user.h>
30 #endif
31 
32 #include "fw_env.h"
33 
34 #define WHITESPACE(c) ((c == '\t') || (c == ' '))
35 
36 #define min(x, y) ({				\
37 	typeof(x) _min1 = (x);			\
38 	typeof(y) _min2 = (y);			\
39 	(void) (&_min1 == &_min2);		\
40 	_min1 < _min2 ? _min1 : _min2; })
41 
42 struct envdev_s {
43 	char devname[16];		/* Device name */
44 	ulong devoff;			/* Device offset */
45 	ulong env_size;			/* environment size */
46 	ulong erase_size;		/* device erase size */
47 	ulong env_sectors;		/* number of environment sectors */
48 	uint8_t mtd_type;		/* type of the MTD device */
49 };
50 
51 static struct envdev_s envdevices[2] =
52 {
53 	{
54 		.mtd_type = MTD_ABSENT,
55 	}, {
56 		.mtd_type = MTD_ABSENT,
57 	},
58 };
59 static int dev_current;
60 
61 #define DEVNAME(i)    envdevices[(i)].devname
62 #define DEVOFFSET(i)  envdevices[(i)].devoff
63 #define ENVSIZE(i)    envdevices[(i)].env_size
64 #define DEVESIZE(i)   envdevices[(i)].erase_size
65 #define ENVSECTORS(i) envdevices[(i)].env_sectors
66 #define DEVTYPE(i)    envdevices[(i)].mtd_type
67 
68 #define CUR_ENVSIZE ENVSIZE(dev_current)
69 
70 #define ENV_SIZE      getenvsize()
71 
72 struct env_image_single {
73 	uint32_t	crc;	/* CRC32 over data bytes    */
74 	char		data[];
75 };
76 
77 struct env_image_redundant {
78 	uint32_t	crc;	/* CRC32 over data bytes    */
79 	unsigned char	flags;	/* active or obsolete */
80 	char		data[];
81 };
82 
83 enum flag_scheme {
84 	FLAG_NONE,
85 	FLAG_BOOLEAN,
86 	FLAG_INCREMENTAL,
87 };
88 
89 struct environment {
90 	void			*image;
91 	uint32_t		*crc;
92 	unsigned char		*flags;
93 	char			*data;
94 	enum flag_scheme	flag_scheme;
95 };
96 
97 static struct environment environment = {
98 	.flag_scheme = FLAG_NONE,
99 };
100 
101 static int HaveRedundEnv = 0;
102 
103 static unsigned char active_flag = 1;
104 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
105 static unsigned char obsolete_flag = 0;
106 
107 #define DEFAULT_ENV_INSTANCE_STATIC
108 #include <env_default.h>
109 
110 static int flash_io (int mode);
111 static char *envmatch (char * s1, char * s2);
112 static int parse_config (void);
113 
114 #if defined(CONFIG_FILE)
115 static int get_config (char *);
116 #endif
117 static inline ulong getenvsize (void)
118 {
119 	ulong rc = CUR_ENVSIZE - sizeof(long);
120 
121 	if (HaveRedundEnv)
122 		rc -= sizeof (char);
123 	return rc;
124 }
125 
126 static char *fw_string_blank(char *s, int noblank)
127 {
128 	int i;
129 	int len = strlen(s);
130 
131 	for (i = 0; i < len; i++, s++) {
132 		if ((noblank && !WHITESPACE(*s)) ||
133 			(!noblank && WHITESPACE(*s)))
134 			break;
135 	}
136 	if (i == len)
137 		return NULL;
138 
139 	return s;
140 }
141 
142 /*
143  * Search the environment for a variable.
144  * Return the value, if found, or NULL, if not found.
145  */
146 char *fw_getenv (char *name)
147 {
148 	char *env, *nxt;
149 
150 	for (env = environment.data; *env; env = nxt + 1) {
151 		char *val;
152 
153 		for (nxt = env; *nxt; ++nxt) {
154 			if (nxt >= &environment.data[ENV_SIZE]) {
155 				fprintf (stderr, "## Error: "
156 					"environment not terminated\n");
157 				return NULL;
158 			}
159 		}
160 		val = envmatch (name, env);
161 		if (!val)
162 			continue;
163 		return val;
164 	}
165 	return NULL;
166 }
167 
168 /*
169  * Search the default environment for a variable.
170  * Return the value, if found, or NULL, if not found.
171  */
172 char *fw_getdefenv(char *name)
173 {
174 	char *env, *nxt;
175 
176 	for (env = default_environment; *env; env = nxt + 1) {
177 		char *val;
178 
179 		for (nxt = env; *nxt; ++nxt) {
180 			if (nxt >= &default_environment[ENV_SIZE]) {
181 				fprintf(stderr, "## Error: "
182 					"default environment not terminated\n");
183 				return NULL;
184 			}
185 		}
186 		val = envmatch(name, env);
187 		if (!val)
188 			continue;
189 		return val;
190 	}
191 	return NULL;
192 }
193 
194 /*
195  * Print the current definition of one, or more, or all
196  * environment variables
197  */
198 int fw_printenv (int argc, char *argv[])
199 {
200 	char *env, *nxt;
201 	int i, n_flag;
202 	int rc = 0;
203 
204 	if (fw_env_open())
205 		return -1;
206 
207 	if (argc == 1) {		/* Print all env variables  */
208 		for (env = environment.data; *env; env = nxt + 1) {
209 			for (nxt = env; *nxt; ++nxt) {
210 				if (nxt >= &environment.data[ENV_SIZE]) {
211 					fprintf (stderr, "## Error: "
212 						"environment not terminated\n");
213 					return -1;
214 				}
215 			}
216 
217 			printf ("%s\n", env);
218 		}
219 		return 0;
220 	}
221 
222 	if (strcmp (argv[1], "-n") == 0) {
223 		n_flag = 1;
224 		++argv;
225 		--argc;
226 		if (argc != 2) {
227 			fprintf (stderr, "## Error: "
228 				"`-n' option requires exactly one argument\n");
229 			return -1;
230 		}
231 	} else {
232 		n_flag = 0;
233 	}
234 
235 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
236 		char *name = argv[i];
237 		char *val = NULL;
238 
239 		for (env = environment.data; *env; env = nxt + 1) {
240 
241 			for (nxt = env; *nxt; ++nxt) {
242 				if (nxt >= &environment.data[ENV_SIZE]) {
243 					fprintf (stderr, "## Error: "
244 						"environment not terminated\n");
245 					return -1;
246 				}
247 			}
248 			val = envmatch (name, env);
249 			if (val) {
250 				if (!n_flag) {
251 					fputs (name, stdout);
252 					putc ('=', stdout);
253 				}
254 				puts (val);
255 				break;
256 			}
257 		}
258 		if (!val) {
259 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
260 			rc = -1;
261 		}
262 	}
263 
264 	return rc;
265 }
266 
267 int fw_env_close(void)
268 {
269 	/*
270 	 * Update CRC
271 	 */
272 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
273 
274 	/* write environment back to flash */
275 	if (flash_io(O_RDWR)) {
276 		fprintf(stderr,
277 			"Error: can't write fw_env to flash\n");
278 			return -1;
279 	}
280 
281 	return 0;
282 }
283 
284 
285 /*
286  * Set/Clear a single variable in the environment.
287  * This is called in sequence to update the environment
288  * in RAM without updating the copy in flash after each set
289  */
290 int fw_env_write(char *name, char *value)
291 {
292 	int len;
293 	char *env, *nxt;
294 	char *oldval = NULL;
295 	int deleting, creating, overwriting;
296 
297 	/*
298 	 * search if variable with this name already exists
299 	 */
300 	for (nxt = env = environment.data; *env; env = nxt + 1) {
301 		for (nxt = env; *nxt; ++nxt) {
302 			if (nxt >= &environment.data[ENV_SIZE]) {
303 				fprintf(stderr, "## Error: "
304 					"environment not terminated\n");
305 				errno = EINVAL;
306 				return -1;
307 			}
308 		}
309 		if ((oldval = envmatch (name, env)) != NULL)
310 			break;
311 	}
312 
313 	deleting = (oldval && !(value && strlen(value)));
314 	creating = (!oldval && (value && strlen(value)));
315 	overwriting = (oldval && (value && strlen(value)));
316 
317 	/* check for permission */
318 	if (deleting) {
319 		if (env_flags_validate_varaccess(name,
320 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
321 			printf("Can't delete \"%s\"\n", name);
322 			errno = EROFS;
323 			return -1;
324 		}
325 	} else if (overwriting) {
326 		if (env_flags_validate_varaccess(name,
327 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
328 			printf("Can't overwrite \"%s\"\n", name);
329 			errno = EROFS;
330 			return -1;
331 		} else if (env_flags_validate_varaccess(name,
332 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
333 			const char *defval = fw_getdefenv(name);
334 
335 			if (defval == NULL)
336 				defval = "";
337 			if (strcmp(oldval, defval)
338 			    != 0) {
339 				printf("Can't overwrite \"%s\"\n", name);
340 				errno = EROFS;
341 				return -1;
342 			}
343 		}
344 	} else if (creating) {
345 		if (env_flags_validate_varaccess(name,
346 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
347 			printf("Can't create \"%s\"\n", name);
348 			errno = EROFS;
349 			return -1;
350 		}
351 	} else
352 		/* Nothing to do */
353 		return 0;
354 
355 	if (deleting || overwriting) {
356 		if (*++nxt == '\0') {
357 			*env = '\0';
358 		} else {
359 			for (;;) {
360 				*env = *nxt++;
361 				if ((*env == '\0') && (*nxt == '\0'))
362 					break;
363 				++env;
364 			}
365 		}
366 		*++env = '\0';
367 	}
368 
369 	/* Delete only ? */
370 	if (!value || !strlen(value))
371 		return 0;
372 
373 	/*
374 	 * Append new definition at the end
375 	 */
376 	for (env = environment.data; *env || *(env + 1); ++env);
377 	if (env > environment.data)
378 		++env;
379 	/*
380 	 * Overflow when:
381 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
382 	 */
383 	len = strlen (name) + 2;
384 	/* add '=' for first arg, ' ' for all others */
385 	len += strlen(value) + 1;
386 
387 	if (len > (&environment.data[ENV_SIZE] - env)) {
388 		fprintf (stderr,
389 			"Error: environment overflow, \"%s\" deleted\n",
390 			name);
391 		return -1;
392 	}
393 
394 	while ((*env = *name++) != '\0')
395 		env++;
396 	*env = '=';
397 	while ((*++env = *value++) != '\0')
398 		;
399 
400 	/* end is marked with double '\0' */
401 	*++env = '\0';
402 
403 	return 0;
404 }
405 
406 /*
407  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
408  * 0	  - OK
409  * EINVAL - need at least 1 argument
410  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
411  *	    modified or deleted
412  *
413  */
414 int fw_setenv(int argc, char *argv[])
415 {
416 	int i;
417 	size_t len;
418 	char *name;
419 	char *value = NULL;
420 
421 	if (argc < 2) {
422 		errno = EINVAL;
423 		return -1;
424 	}
425 
426 	if (fw_env_open()) {
427 		fprintf(stderr, "Error: environment not initialized\n");
428 		return -1;
429 	}
430 
431 	name = argv[1];
432 
433 	if (env_flags_validate_env_set_params(argc, argv) < 0)
434 		return 1;
435 
436 	len = 0;
437 	for (i = 2; i < argc; ++i) {
438 		char *val = argv[i];
439 		size_t val_len = strlen(val);
440 
441 		if (value)
442 			value[len - 1] = ' ';
443 		value = realloc(value, len + val_len + 1);
444 		if (!value) {
445 			fprintf(stderr,
446 				"Cannot malloc %zu bytes: %s\n",
447 				len, strerror(errno));
448 			return -1;
449 		}
450 
451 		memcpy(value + len, val, val_len);
452 		len += val_len;
453 		value[len++] = '\0';
454 	}
455 
456 	fw_env_write(name, value);
457 
458 	free(value);
459 
460 	return fw_env_close();
461 }
462 
463 /*
464  * Parse  a file  and configure the u-boot variables.
465  * The script file has a very simple format, as follows:
466  *
467  * Each line has a couple with name, value:
468  * <white spaces>variable_name<white spaces>variable_value
469  *
470  * Both variable_name and variable_value are interpreted as strings.
471  * Any character after <white spaces> and before ending \r\n is interpreted
472  * as variable's value (no comment allowed on these lines !)
473  *
474  * Comments are allowed if the first character in the line is #
475  *
476  * Returns -1 and sets errno error codes:
477  * 0	  - OK
478  * -1     - Error
479  */
480 int fw_parse_script(char *fname)
481 {
482 	FILE *fp;
483 	char dump[1024];	/* Maximum line length in the file */
484 	char *name;
485 	char *val;
486 	int lineno = 0;
487 	int len;
488 	int ret = 0;
489 
490 	if (fw_env_open()) {
491 		fprintf(stderr, "Error: environment not initialized\n");
492 		return -1;
493 	}
494 
495 	if (strcmp(fname, "-") == 0)
496 		fp = stdin;
497 	else {
498 		fp = fopen(fname, "r");
499 		if (fp == NULL) {
500 			fprintf(stderr, "I cannot open %s for reading\n",
501 				 fname);
502 			return -1;
503 		}
504 	}
505 
506 	while (fgets(dump, sizeof(dump), fp)) {
507 		lineno++;
508 		len = strlen(dump);
509 
510 		/*
511 		 * Read a whole line from the file. If the line is too long
512 		 * or is not terminated, reports an error and exit.
513 		 */
514 		if (dump[len - 1] != '\n') {
515 			fprintf(stderr,
516 			"Line %d not corrected terminated or too long\n",
517 				lineno);
518 			ret = -1;
519 			break;
520 		}
521 
522 		/* Drop ending line feed / carriage return */
523 		while (len > 0 && (dump[len - 1] == '\n' ||
524 				dump[len - 1] == '\r')) {
525 			dump[len - 1] = '\0';
526 			len--;
527 		}
528 
529 		/* Skip comment or empty lines */
530 		if ((len == 0) || dump[0] == '#')
531 			continue;
532 
533 		/*
534 		 * Search for variable's name,
535 		 * remove leading whitespaces
536 		 */
537 		name = fw_string_blank(dump, 1);
538 		if (!name)
539 			continue;
540 
541 		/* The first white space is the end of variable name */
542 		val = fw_string_blank(name, 0);
543 		len = strlen(name);
544 		if (val) {
545 			*val++ = '\0';
546 			if ((val - name) < len)
547 				val = fw_string_blank(val, 1);
548 			else
549 				val = NULL;
550 		}
551 
552 #ifdef DEBUG
553 		fprintf(stderr, "Setting %s : %s\n",
554 			name, val ? val : " removed");
555 #endif
556 
557 		if (env_flags_validate_type(name, val) < 0) {
558 			ret = -1;
559 			break;
560 		}
561 
562 		/*
563 		 * If there is an error setting a variable,
564 		 * try to save the environment and returns an error
565 		 */
566 		if (fw_env_write(name, val)) {
567 			fprintf(stderr,
568 			"fw_env_write returns with error : %s\n",
569 				strerror(errno));
570 			ret = -1;
571 			break;
572 		}
573 
574 	}
575 
576 	/* Close file if not stdin */
577 	if (strcmp(fname, "-") != 0)
578 		fclose(fp);
579 
580 	ret |= fw_env_close();
581 
582 	return ret;
583 
584 }
585 
586 /*
587  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
588  * 0	- block is good
589  * > 0	- block is bad
590  * < 0	- failed to test
591  */
592 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
593 {
594 	if (mtd_type == MTD_NANDFLASH) {
595 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
596 
597 		if (badblock < 0) {
598 			perror ("Cannot read bad block mark");
599 			return badblock;
600 		}
601 
602 		if (badblock) {
603 #ifdef DEBUG
604 			fprintf (stderr, "Bad block at 0x%llx, "
605 				 "skipping\n", *blockstart);
606 #endif
607 			return badblock;
608 		}
609 	}
610 
611 	return 0;
612 }
613 
614 /*
615  * Read data from flash at an offset into a provided buffer. On NAND it skips
616  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
617  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
618  */
619 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
620 			   off_t offset, uint8_t mtd_type)
621 {
622 	size_t blocklen;	/* erase / write length - one block on NAND,
623 				   0 on NOR */
624 	size_t processed = 0;	/* progress counter */
625 	size_t readlen = count;	/* current read length */
626 	off_t top_of_range;	/* end of the last block we may use */
627 	off_t block_seek;	/* offset inside the current block to the start
628 				   of the data */
629 	loff_t blockstart;	/* running start of the current block -
630 				   MEMGETBADBLOCK needs 64 bits */
631 	int rc;
632 
633 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
634 
635 	/* Offset inside a block */
636 	block_seek = offset - blockstart;
637 
638 	if (mtd_type == MTD_NANDFLASH) {
639 		/*
640 		 * NAND: calculate which blocks we are reading. We have
641 		 * to read one block at a time to skip bad blocks.
642 		 */
643 		blocklen = DEVESIZE (dev);
644 
645 		/*
646 		 * To calculate the top of the range, we have to use the
647 		 * global DEVOFFSET (dev), which can be different from offset
648 		 */
649 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
650 				ENVSECTORS (dev)) * blocklen;
651 
652 		/* Limit to one block for the first read */
653 		if (readlen > blocklen - block_seek)
654 			readlen = blocklen - block_seek;
655 	} else {
656 		blocklen = 0;
657 		top_of_range = offset + count;
658 	}
659 
660 	/* This only runs once on NOR flash */
661 	while (processed < count) {
662 		rc = flash_bad_block (fd, mtd_type, &blockstart);
663 		if (rc < 0)		/* block test failed */
664 			return -1;
665 
666 		if (blockstart + block_seek + readlen > top_of_range) {
667 			/* End of range is reached */
668 			fprintf (stderr,
669 				 "Too few good blocks within range\n");
670 			return -1;
671 		}
672 
673 		if (rc) {		/* block is bad */
674 			blockstart += blocklen;
675 			continue;
676 		}
677 
678 		/*
679 		 * If a block is bad, we retry in the next block at the same
680 		 * offset - see common/env_nand.c::writeenv()
681 		 */
682 		lseek (fd, blockstart + block_seek, SEEK_SET);
683 
684 		rc = read (fd, buf + processed, readlen);
685 		if (rc != readlen) {
686 			fprintf (stderr, "Read error on %s: %s\n",
687 				 DEVNAME (dev), strerror (errno));
688 			return -1;
689 		}
690 #ifdef DEBUG
691 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
692 			 rc, blockstart + block_seek, DEVNAME(dev));
693 #endif
694 		processed += readlen;
695 		readlen = min (blocklen, count - processed);
696 		block_seek = 0;
697 		blockstart += blocklen;
698 	}
699 
700 	return processed;
701 }
702 
703 /*
704  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
705  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
706  * erase and write the whole data at once.
707  */
708 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
709 			    off_t offset, uint8_t mtd_type)
710 {
711 	void *data;
712 	struct erase_info_user erase;
713 	size_t blocklen;	/* length of NAND block / NOR erase sector */
714 	size_t erase_len;	/* whole area that can be erased - may include
715 				   bad blocks */
716 	size_t erasesize;	/* erase / write length - one block on NAND,
717 				   whole area on NOR */
718 	size_t processed = 0;	/* progress counter */
719 	size_t write_total;	/* total size to actually write - excluding
720 				   bad blocks */
721 	off_t erase_offset;	/* offset to the first erase block (aligned)
722 				   below offset */
723 	off_t block_seek;	/* offset inside the erase block to the start
724 				   of the data */
725 	off_t top_of_range;	/* end of the last block we may use */
726 	loff_t blockstart;	/* running start of the current block -
727 				   MEMGETBADBLOCK needs 64 bits */
728 	int rc;
729 
730 	/*
731 	 * For mtd devices only offset and size of the environment do matter
732 	 */
733 	if (mtd_type == MTD_ABSENT) {
734 		blocklen = count;
735 		top_of_range = offset + count;
736 		erase_len = blocklen;
737 		blockstart = offset;
738 		block_seek = 0;
739 		write_total = blocklen;
740 	} else {
741 		blocklen = DEVESIZE(dev);
742 
743 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
744 					ENVSECTORS(dev)) * blocklen;
745 
746 		erase_offset = (offset / blocklen) * blocklen;
747 
748 		/* Maximum area we may use */
749 		erase_len = top_of_range - erase_offset;
750 
751 		blockstart = erase_offset;
752 		/* Offset inside a block */
753 		block_seek = offset - erase_offset;
754 
755 		/*
756 		 * Data size we actually write: from the start of the block
757 		 * to the start of the data, then count bytes of data, and
758 		 * to the end of the block
759 		 */
760 		write_total = ((block_seek + count + blocklen - 1) /
761 							blocklen) * blocklen;
762 	}
763 
764 	/*
765 	 * Support data anywhere within erase sectors: read out the complete
766 	 * area to be erased, replace the environment image, write the whole
767 	 * block back again.
768 	 */
769 	if (write_total > count) {
770 		data = malloc (erase_len);
771 		if (!data) {
772 			fprintf (stderr,
773 				 "Cannot malloc %zu bytes: %s\n",
774 				 erase_len, strerror (errno));
775 			return -1;
776 		}
777 
778 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
779 				     mtd_type);
780 		if (write_total != rc)
781 			return -1;
782 
783 #ifdef DEBUG
784 		fprintf(stderr, "Preserving data ");
785 		if (block_seek != 0)
786 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
787 		if (block_seek + count != write_total) {
788 			if (block_seek != 0)
789 				fprintf(stderr, " and ");
790 			fprintf(stderr, "0x%lx - 0x%x",
791 				block_seek + count, write_total - 1);
792 		}
793 		fprintf(stderr, "\n");
794 #endif
795 		/* Overwrite the old environment */
796 		memcpy (data + block_seek, buf, count);
797 	} else {
798 		/*
799 		 * We get here, iff offset is block-aligned and count is a
800 		 * multiple of blocklen - see write_total calculation above
801 		 */
802 		data = buf;
803 	}
804 
805 	if (mtd_type == MTD_NANDFLASH) {
806 		/*
807 		 * NAND: calculate which blocks we are writing. We have
808 		 * to write one block at a time to skip bad blocks.
809 		 */
810 		erasesize = blocklen;
811 	} else {
812 		erasesize = erase_len;
813 	}
814 
815 	erase.length = erasesize;
816 
817 	/* This only runs once on NOR flash and SPI-dataflash */
818 	while (processed < write_total) {
819 		rc = flash_bad_block (fd, mtd_type, &blockstart);
820 		if (rc < 0)		/* block test failed */
821 			return rc;
822 
823 		if (blockstart + erasesize > top_of_range) {
824 			fprintf (stderr, "End of range reached, aborting\n");
825 			return -1;
826 		}
827 
828 		if (rc) {		/* block is bad */
829 			blockstart += blocklen;
830 			continue;
831 		}
832 
833 		if (mtd_type != MTD_ABSENT) {
834 			erase.start = blockstart;
835 			ioctl(fd, MEMUNLOCK, &erase);
836 			/* These do not need an explicit erase cycle */
837 			if (mtd_type != MTD_DATAFLASH)
838 				if (ioctl(fd, MEMERASE, &erase) != 0) {
839 					fprintf(stderr,
840 						"MTD erase error on %s: %s\n",
841 						DEVNAME(dev), strerror(errno));
842 					return -1;
843 				}
844 		}
845 
846 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
847 			fprintf (stderr,
848 				 "Seek error on %s: %s\n",
849 				 DEVNAME (dev), strerror (errno));
850 			return -1;
851 		}
852 
853 #ifdef DEBUG
854 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
855 			blockstart);
856 #endif
857 		if (write (fd, data + processed, erasesize) != erasesize) {
858 			fprintf (stderr, "Write error on %s: %s\n",
859 				 DEVNAME (dev), strerror (errno));
860 			return -1;
861 		}
862 
863 		if (mtd_type != MTD_ABSENT)
864 			ioctl(fd, MEMLOCK, &erase);
865 
866 		processed  += blocklen;
867 		block_seek = 0;
868 		blockstart += blocklen;
869 	}
870 
871 	if (write_total > count)
872 		free (data);
873 
874 	return processed;
875 }
876 
877 /*
878  * Set obsolete flag at offset - NOR flash only
879  */
880 static int flash_flag_obsolete (int dev, int fd, off_t offset)
881 {
882 	int rc;
883 	struct erase_info_user erase;
884 
885 	erase.start  = DEVOFFSET (dev);
886 	erase.length = DEVESIZE (dev);
887 	/* This relies on the fact, that obsolete_flag == 0 */
888 	rc = lseek (fd, offset, SEEK_SET);
889 	if (rc < 0) {
890 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
891 			 DEVNAME (dev));
892 		return rc;
893 	}
894 	ioctl (fd, MEMUNLOCK, &erase);
895 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
896 	ioctl (fd, MEMLOCK, &erase);
897 	if (rc < 0)
898 		perror ("Could not set obsolete flag");
899 
900 	return rc;
901 }
902 
903 static int flash_write (int fd_current, int fd_target, int dev_target)
904 {
905 	int rc;
906 
907 	switch (environment.flag_scheme) {
908 	case FLAG_NONE:
909 		break;
910 	case FLAG_INCREMENTAL:
911 		(*environment.flags)++;
912 		break;
913 	case FLAG_BOOLEAN:
914 		*environment.flags = active_flag;
915 		break;
916 	default:
917 		fprintf (stderr, "Unimplemented flash scheme %u \n",
918 			 environment.flag_scheme);
919 		return -1;
920 	}
921 
922 #ifdef DEBUG
923 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
924 		DEVOFFSET (dev_target), DEVNAME (dev_target));
925 #endif
926 	rc = flash_write_buf(dev_target, fd_target, environment.image,
927 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
928 			      DEVTYPE(dev_target));
929 	if (rc < 0)
930 		return rc;
931 
932 	if (environment.flag_scheme == FLAG_BOOLEAN) {
933 		/* Have to set obsolete flag */
934 		off_t offset = DEVOFFSET (dev_current) +
935 			offsetof (struct env_image_redundant, flags);
936 #ifdef DEBUG
937 		fprintf(stderr,
938 			"Setting obsolete flag in environment at 0x%lx on %s\n",
939 			DEVOFFSET (dev_current), DEVNAME (dev_current));
940 #endif
941 		flash_flag_obsolete (dev_current, fd_current, offset);
942 	}
943 
944 	return 0;
945 }
946 
947 static int flash_read (int fd)
948 {
949 	struct mtd_info_user mtdinfo;
950 	struct stat st;
951 	int rc;
952 
953 	rc = fstat(fd, &st);
954 	if (rc < 0) {
955 		fprintf(stderr, "Cannot stat the file %s\n",
956 			DEVNAME(dev_current));
957 		return -1;
958 	}
959 
960 	if (S_ISCHR(st.st_mode)) {
961 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
962 		if (rc < 0) {
963 			fprintf(stderr, "Cannot get MTD information for %s\n",
964 				DEVNAME(dev_current));
965 			return -1;
966 		}
967 		if (mtdinfo.type != MTD_NORFLASH &&
968 		    mtdinfo.type != MTD_NANDFLASH &&
969 		    mtdinfo.type != MTD_DATAFLASH &&
970 		    mtdinfo.type != MTD_UBIVOLUME) {
971 			fprintf (stderr, "Unsupported flash type %u on %s\n",
972 				 mtdinfo.type, DEVNAME(dev_current));
973 			return -1;
974 		}
975 	} else {
976 		memset(&mtdinfo, 0, sizeof(mtdinfo));
977 		mtdinfo.type = MTD_ABSENT;
978 	}
979 
980 	DEVTYPE(dev_current) = mtdinfo.type;
981 
982 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
983 			     DEVOFFSET (dev_current), mtdinfo.type);
984 
985 	return (rc != CUR_ENVSIZE) ? -1 : 0;
986 }
987 
988 static int flash_io (int mode)
989 {
990 	int fd_current, fd_target, rc, dev_target;
991 
992 	/* dev_current: fd_current, erase_current */
993 	fd_current = open (DEVNAME (dev_current), mode);
994 	if (fd_current < 0) {
995 		fprintf (stderr,
996 			 "Can't open %s: %s\n",
997 			 DEVNAME (dev_current), strerror (errno));
998 		return -1;
999 	}
1000 
1001 	if (mode == O_RDWR) {
1002 		if (HaveRedundEnv) {
1003 			/* switch to next partition for writing */
1004 			dev_target = !dev_current;
1005 			/* dev_target: fd_target, erase_target */
1006 			fd_target = open (DEVNAME (dev_target), mode);
1007 			if (fd_target < 0) {
1008 				fprintf (stderr,
1009 					 "Can't open %s: %s\n",
1010 					 DEVNAME (dev_target),
1011 					 strerror (errno));
1012 				rc = -1;
1013 				goto exit;
1014 			}
1015 		} else {
1016 			dev_target = dev_current;
1017 			fd_target = fd_current;
1018 		}
1019 
1020 		rc = flash_write (fd_current, fd_target, dev_target);
1021 
1022 		if (HaveRedundEnv) {
1023 			if (close (fd_target)) {
1024 				fprintf (stderr,
1025 					"I/O error on %s: %s\n",
1026 					DEVNAME (dev_target),
1027 					strerror (errno));
1028 				rc = -1;
1029 			}
1030 		}
1031 	} else {
1032 		rc = flash_read (fd_current);
1033 	}
1034 
1035 exit:
1036 	if (close (fd_current)) {
1037 		fprintf (stderr,
1038 			 "I/O error on %s: %s\n",
1039 			 DEVNAME (dev_current), strerror (errno));
1040 		return -1;
1041 	}
1042 
1043 	return rc;
1044 }
1045 
1046 /*
1047  * s1 is either a simple 'name', or a 'name=value' pair.
1048  * s2 is a 'name=value' pair.
1049  * If the names match, return the value of s2, else NULL.
1050  */
1051 
1052 static char *envmatch (char * s1, char * s2)
1053 {
1054 	if (s1 == NULL || s2 == NULL)
1055 		return NULL;
1056 
1057 	while (*s1 == *s2++)
1058 		if (*s1++ == '=')
1059 			return s2;
1060 	if (*s1 == '\0' && *(s2 - 1) == '=')
1061 		return s2;
1062 	return NULL;
1063 }
1064 
1065 /*
1066  * Prevent confusion if running from erased flash memory
1067  */
1068 int fw_env_open(void)
1069 {
1070 	int crc0, crc0_ok;
1071 	unsigned char flag0;
1072 	void *addr0;
1073 
1074 	int crc1, crc1_ok;
1075 	unsigned char flag1;
1076 	void *addr1;
1077 
1078 	struct env_image_single *single;
1079 	struct env_image_redundant *redundant;
1080 
1081 	if (parse_config ())		/* should fill envdevices */
1082 		return -1;
1083 
1084 	addr0 = calloc(1, CUR_ENVSIZE);
1085 	if (addr0 == NULL) {
1086 		fprintf(stderr,
1087 			"Not enough memory for environment (%ld bytes)\n",
1088 			CUR_ENVSIZE);
1089 		return -1;
1090 	}
1091 
1092 	/* read environment from FLASH to local buffer */
1093 	environment.image = addr0;
1094 
1095 	if (HaveRedundEnv) {
1096 		redundant = addr0;
1097 		environment.crc		= &redundant->crc;
1098 		environment.flags	= &redundant->flags;
1099 		environment.data	= redundant->data;
1100 	} else {
1101 		single = addr0;
1102 		environment.crc		= &single->crc;
1103 		environment.flags	= NULL;
1104 		environment.data	= single->data;
1105 	}
1106 
1107 	dev_current = 0;
1108 	if (flash_io (O_RDONLY))
1109 		return -1;
1110 
1111 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1112 	crc0_ok = (crc0 == *environment.crc);
1113 	if (!HaveRedundEnv) {
1114 		if (!crc0_ok) {
1115 			fprintf (stderr,
1116 				"Warning: Bad CRC, using default environment\n");
1117 			memcpy(environment.data, default_environment, sizeof default_environment);
1118 		}
1119 	} else {
1120 		flag0 = *environment.flags;
1121 
1122 		dev_current = 1;
1123 		addr1 = calloc(1, CUR_ENVSIZE);
1124 		if (addr1 == NULL) {
1125 			fprintf(stderr,
1126 				"Not enough memory for environment (%ld bytes)\n",
1127 				CUR_ENVSIZE);
1128 			return -1;
1129 		}
1130 		redundant = addr1;
1131 
1132 		/*
1133 		 * have to set environment.image for flash_read(), careful -
1134 		 * other pointers in environment still point inside addr0
1135 		 */
1136 		environment.image = addr1;
1137 		if (flash_io (O_RDONLY))
1138 			return -1;
1139 
1140 		/* Check flag scheme compatibility */
1141 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1142 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1143 			environment.flag_scheme = FLAG_BOOLEAN;
1144 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1145 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1146 			environment.flag_scheme = FLAG_INCREMENTAL;
1147 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1148 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1149 			environment.flag_scheme = FLAG_BOOLEAN;
1150 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1151 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1152 			environment.flag_scheme = FLAG_INCREMENTAL;
1153 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1154 			   DEVTYPE(!dev_current) == MTD_ABSENT) {
1155 			environment.flag_scheme = FLAG_INCREMENTAL;
1156 		} else {
1157 			fprintf (stderr, "Incompatible flash types!\n");
1158 			return -1;
1159 		}
1160 
1161 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1162 		crc1_ok = (crc1 == redundant->crc);
1163 		flag1 = redundant->flags;
1164 
1165 		if (crc0_ok && !crc1_ok) {
1166 			dev_current = 0;
1167 		} else if (!crc0_ok && crc1_ok) {
1168 			dev_current = 1;
1169 		} else if (!crc0_ok && !crc1_ok) {
1170 			fprintf (stderr,
1171 				"Warning: Bad CRC, using default environment\n");
1172 			memcpy (environment.data, default_environment,
1173 				sizeof default_environment);
1174 			dev_current = 0;
1175 		} else {
1176 			switch (environment.flag_scheme) {
1177 			case FLAG_BOOLEAN:
1178 				if (flag0 == active_flag &&
1179 				    flag1 == obsolete_flag) {
1180 					dev_current = 0;
1181 				} else if (flag0 == obsolete_flag &&
1182 					   flag1 == active_flag) {
1183 					dev_current = 1;
1184 				} else if (flag0 == flag1) {
1185 					dev_current = 0;
1186 				} else if (flag0 == 0xFF) {
1187 					dev_current = 0;
1188 				} else if (flag1 == 0xFF) {
1189 					dev_current = 1;
1190 				} else {
1191 					dev_current = 0;
1192 				}
1193 				break;
1194 			case FLAG_INCREMENTAL:
1195 				if (flag0 == 255 && flag1 == 0)
1196 					dev_current = 1;
1197 				else if ((flag1 == 255 && flag0 == 0) ||
1198 					 flag0 >= flag1)
1199 					dev_current = 0;
1200 				else /* flag1 > flag0 */
1201 					dev_current = 1;
1202 				break;
1203 			default:
1204 				fprintf (stderr, "Unknown flag scheme %u \n",
1205 					 environment.flag_scheme);
1206 				return -1;
1207 			}
1208 		}
1209 
1210 		/*
1211 		 * If we are reading, we don't need the flag and the CRC any
1212 		 * more, if we are writing, we will re-calculate CRC and update
1213 		 * flags before writing out
1214 		 */
1215 		if (dev_current) {
1216 			environment.image	= addr1;
1217 			environment.crc		= &redundant->crc;
1218 			environment.flags	= &redundant->flags;
1219 			environment.data	= redundant->data;
1220 			free (addr0);
1221 		} else {
1222 			environment.image	= addr0;
1223 			/* Other pointers are already set */
1224 			free (addr1);
1225 		}
1226 #ifdef DEBUG
1227 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1228 #endif
1229 	}
1230 	return 0;
1231 }
1232 
1233 
1234 static int parse_config ()
1235 {
1236 	struct stat st;
1237 
1238 #if defined(CONFIG_FILE)
1239 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1240 	if (get_config (CONFIG_FILE)) {
1241 		fprintf (stderr,
1242 			"Cannot parse config file: %s\n", strerror (errno));
1243 		return -1;
1244 	}
1245 #else
1246 	strcpy (DEVNAME (0), DEVICE1_NAME);
1247 	DEVOFFSET (0) = DEVICE1_OFFSET;
1248 	ENVSIZE (0) = ENV1_SIZE;
1249 	/* Default values are: erase-size=env-size, #sectors=1 */
1250 	DEVESIZE (0) = ENVSIZE (0);
1251 	ENVSECTORS (0) = 1;
1252 #ifdef DEVICE1_ESIZE
1253 	DEVESIZE (0) = DEVICE1_ESIZE;
1254 #endif
1255 #ifdef DEVICE1_ENVSECTORS
1256 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1257 #endif
1258 
1259 #ifdef HAVE_REDUND
1260 	strcpy (DEVNAME (1), DEVICE2_NAME);
1261 	DEVOFFSET (1) = DEVICE2_OFFSET;
1262 	ENVSIZE (1) = ENV2_SIZE;
1263 	/* Default values are: erase-size=env-size, #sectors=1 */
1264 	DEVESIZE (1) = ENVSIZE (1);
1265 	ENVSECTORS (1) = 1;
1266 #ifdef DEVICE2_ESIZE
1267 	DEVESIZE (1) = DEVICE2_ESIZE;
1268 #endif
1269 #ifdef DEVICE2_ENVSECTORS
1270 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1271 #endif
1272 	HaveRedundEnv = 1;
1273 #endif
1274 #endif
1275 	if (stat (DEVNAME (0), &st)) {
1276 		fprintf (stderr,
1277 			"Cannot access MTD device %s: %s\n",
1278 			DEVNAME (0), strerror (errno));
1279 		return -1;
1280 	}
1281 
1282 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1283 		fprintf (stderr,
1284 			"Cannot access MTD device %s: %s\n",
1285 			DEVNAME (1), strerror (errno));
1286 		return -1;
1287 	}
1288 	return 0;
1289 }
1290 
1291 #if defined(CONFIG_FILE)
1292 static int get_config (char *fname)
1293 {
1294 	FILE *fp;
1295 	int i = 0;
1296 	int rc;
1297 	char dump[128];
1298 
1299 	fp = fopen (fname, "r");
1300 	if (fp == NULL)
1301 		return -1;
1302 
1303 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1304 		/* Skip incomplete conversions and comment strings */
1305 		if (dump[0] == '#')
1306 			continue;
1307 
1308 		rc = sscanf (dump, "%s %lx %lx %lx %lx",
1309 			     DEVNAME (i),
1310 			     &DEVOFFSET (i),
1311 			     &ENVSIZE (i),
1312 			     &DEVESIZE (i),
1313 			     &ENVSECTORS (i));
1314 
1315 		if (rc < 3)
1316 			continue;
1317 
1318 		if (rc < 4)
1319 			/* Assume the erase size is the same as the env-size */
1320 			DEVESIZE(i) = ENVSIZE(i);
1321 
1322 		if (rc < 5)
1323 			/* Default - 1 sector */
1324 			ENVSECTORS (i) = 1;
1325 
1326 		i++;
1327 	}
1328 	fclose (fp);
1329 
1330 	HaveRedundEnv = i - 1;
1331 	if (!i) {			/* No valid entries found */
1332 		errno = EINVAL;
1333 		return -1;
1334 	} else
1335 		return 0;
1336 }
1337 #endif
1338