xref: /openbmc/u-boot/tools/env/fw_env.c (revision c9aa831e)
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  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 
27 #include <errno.h>
28 #include <env_flags.h>
29 #include <fcntl.h>
30 #include <linux/stringify.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <stddef.h>
34 #include <string.h>
35 #include <sys/types.h>
36 #include <sys/ioctl.h>
37 #include <sys/stat.h>
38 #include <unistd.h>
39 
40 #ifdef MTD_OLD
41 # include <stdint.h>
42 # include <linux/mtd/mtd.h>
43 #else
44 # define  __user	/* nothing */
45 # include <mtd/mtd-user.h>
46 #endif
47 
48 #include "fw_env.h"
49 
50 #define WHITESPACE(c) ((c == '\t') || (c == ' '))
51 
52 #define min(x, y) ({				\
53 	typeof(x) _min1 = (x);			\
54 	typeof(y) _min2 = (y);			\
55 	(void) (&_min1 == &_min2);		\
56 	_min1 < _min2 ? _min1 : _min2; })
57 
58 struct envdev_s {
59 	char devname[16];		/* Device name */
60 	ulong devoff;			/* Device offset */
61 	ulong env_size;			/* environment size */
62 	ulong erase_size;		/* device erase size */
63 	ulong env_sectors;		/* number of environment sectors */
64 	uint8_t mtd_type;		/* type of the MTD device */
65 };
66 
67 static struct envdev_s envdevices[2] =
68 {
69 	{
70 		.mtd_type = MTD_ABSENT,
71 	}, {
72 		.mtd_type = MTD_ABSENT,
73 	},
74 };
75 static int dev_current;
76 
77 #define DEVNAME(i)    envdevices[(i)].devname
78 #define DEVOFFSET(i)  envdevices[(i)].devoff
79 #define ENVSIZE(i)    envdevices[(i)].env_size
80 #define DEVESIZE(i)   envdevices[(i)].erase_size
81 #define ENVSECTORS(i) envdevices[(i)].env_sectors
82 #define DEVTYPE(i)    envdevices[(i)].mtd_type
83 
84 #define CUR_ENVSIZE ENVSIZE(dev_current)
85 
86 #define ENV_SIZE      getenvsize()
87 
88 struct env_image_single {
89 	uint32_t	crc;	/* CRC32 over data bytes    */
90 	char		data[];
91 };
92 
93 struct env_image_redundant {
94 	uint32_t	crc;	/* CRC32 over data bytes    */
95 	unsigned char	flags;	/* active or obsolete */
96 	char		data[];
97 };
98 
99 enum flag_scheme {
100 	FLAG_NONE,
101 	FLAG_BOOLEAN,
102 	FLAG_INCREMENTAL,
103 };
104 
105 struct environment {
106 	void			*image;
107 	uint32_t		*crc;
108 	unsigned char		*flags;
109 	char			*data;
110 	enum flag_scheme	flag_scheme;
111 };
112 
113 static struct environment environment = {
114 	.flag_scheme = FLAG_NONE,
115 };
116 
117 static int HaveRedundEnv = 0;
118 
119 static unsigned char active_flag = 1;
120 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
121 static unsigned char obsolete_flag = 0;
122 
123 #define DEFAULT_ENV_INSTANCE_STATIC
124 #include <env_default.h>
125 
126 static int flash_io (int mode);
127 static char *envmatch (char * s1, char * s2);
128 static int parse_config (void);
129 
130 #if defined(CONFIG_FILE)
131 static int get_config (char *);
132 #endif
133 static inline ulong getenvsize (void)
134 {
135 	ulong rc = CUR_ENVSIZE - sizeof(long);
136 
137 	if (HaveRedundEnv)
138 		rc -= sizeof (char);
139 	return rc;
140 }
141 
142 static char *fw_string_blank(char *s, int noblank)
143 {
144 	int i;
145 	int len = strlen(s);
146 
147 	for (i = 0; i < len; i++, s++) {
148 		if ((noblank && !WHITESPACE(*s)) ||
149 			(!noblank && WHITESPACE(*s)))
150 			break;
151 	}
152 	if (i == len)
153 		return NULL;
154 
155 	return s;
156 }
157 
158 /*
159  * Search the environment for a variable.
160  * Return the value, if found, or NULL, if not found.
161  */
162 char *fw_getenv (char *name)
163 {
164 	char *env, *nxt;
165 
166 	for (env = environment.data; *env; env = nxt + 1) {
167 		char *val;
168 
169 		for (nxt = env; *nxt; ++nxt) {
170 			if (nxt >= &environment.data[ENV_SIZE]) {
171 				fprintf (stderr, "## Error: "
172 					"environment not terminated\n");
173 				return NULL;
174 			}
175 		}
176 		val = envmatch (name, env);
177 		if (!val)
178 			continue;
179 		return val;
180 	}
181 	return NULL;
182 }
183 
184 /*
185  * Search the default environment for a variable.
186  * Return the value, if found, or NULL, if not found.
187  */
188 char *fw_getdefenv(char *name)
189 {
190 	char *env, *nxt;
191 
192 	for (env = default_environment; *env; env = nxt + 1) {
193 		char *val;
194 
195 		for (nxt = env; *nxt; ++nxt) {
196 			if (nxt >= &default_environment[ENV_SIZE]) {
197 				fprintf(stderr, "## Error: "
198 					"default environment not terminated\n");
199 				return NULL;
200 			}
201 		}
202 		val = envmatch(name, env);
203 		if (!val)
204 			continue;
205 		return val;
206 	}
207 	return NULL;
208 }
209 
210 /*
211  * Print the current definition of one, or more, or all
212  * environment variables
213  */
214 int fw_printenv (int argc, char *argv[])
215 {
216 	char *env, *nxt;
217 	int i, n_flag;
218 	int rc = 0;
219 
220 	if (fw_env_open())
221 		return -1;
222 
223 	if (argc == 1) {		/* Print all env variables  */
224 		for (env = environment.data; *env; env = nxt + 1) {
225 			for (nxt = env; *nxt; ++nxt) {
226 				if (nxt >= &environment.data[ENV_SIZE]) {
227 					fprintf (stderr, "## Error: "
228 						"environment not terminated\n");
229 					return -1;
230 				}
231 			}
232 
233 			printf ("%s\n", env);
234 		}
235 		return 0;
236 	}
237 
238 	if (strcmp (argv[1], "-n") == 0) {
239 		n_flag = 1;
240 		++argv;
241 		--argc;
242 		if (argc != 2) {
243 			fprintf (stderr, "## Error: "
244 				"`-n' option requires exactly one argument\n");
245 			return -1;
246 		}
247 	} else {
248 		n_flag = 0;
249 	}
250 
251 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
252 		char *name = argv[i];
253 		char *val = NULL;
254 
255 		for (env = environment.data; *env; env = nxt + 1) {
256 
257 			for (nxt = env; *nxt; ++nxt) {
258 				if (nxt >= &environment.data[ENV_SIZE]) {
259 					fprintf (stderr, "## Error: "
260 						"environment not terminated\n");
261 					return -1;
262 				}
263 			}
264 			val = envmatch (name, env);
265 			if (val) {
266 				if (!n_flag) {
267 					fputs (name, stdout);
268 					putc ('=', stdout);
269 				}
270 				puts (val);
271 				break;
272 			}
273 		}
274 		if (!val) {
275 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
276 			rc = -1;
277 		}
278 	}
279 
280 	return rc;
281 }
282 
283 int fw_env_close(void)
284 {
285 	/*
286 	 * Update CRC
287 	 */
288 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
289 
290 	/* write environment back to flash */
291 	if (flash_io(O_RDWR)) {
292 		fprintf(stderr,
293 			"Error: can't write fw_env to flash\n");
294 			return -1;
295 	}
296 
297 	return 0;
298 }
299 
300 
301 /*
302  * Set/Clear a single variable in the environment.
303  * This is called in sequence to update the environment
304  * in RAM without updating the copy in flash after each set
305  */
306 int fw_env_write(char *name, char *value)
307 {
308 	int len;
309 	char *env, *nxt;
310 	char *oldval = NULL;
311 	int deleting, creating, overwriting;
312 
313 	/*
314 	 * search if variable with this name already exists
315 	 */
316 	for (nxt = env = environment.data; *env; env = nxt + 1) {
317 		for (nxt = env; *nxt; ++nxt) {
318 			if (nxt >= &environment.data[ENV_SIZE]) {
319 				fprintf(stderr, "## Error: "
320 					"environment not terminated\n");
321 				errno = EINVAL;
322 				return -1;
323 			}
324 		}
325 		if ((oldval = envmatch (name, env)) != NULL)
326 			break;
327 	}
328 
329 	deleting = (oldval && !(value && strlen(value)));
330 	creating = (!oldval && (value && strlen(value)));
331 	overwriting = (oldval && (value && strlen(value)));
332 
333 	/* check for permission */
334 	if (deleting) {
335 		if (env_flags_validate_varaccess(name,
336 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
337 			printf("Can't delete \"%s\"\n", name);
338 			errno = EROFS;
339 			return -1;
340 		}
341 	} else if (overwriting) {
342 		if (env_flags_validate_varaccess(name,
343 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
344 			printf("Can't overwrite \"%s\"\n", name);
345 			errno = EROFS;
346 			return -1;
347 		} else if (env_flags_validate_varaccess(name,
348 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
349 			const char *defval = fw_getdefenv(name);
350 
351 			if (defval == NULL)
352 				defval = "";
353 			if (strcmp(oldval, defval)
354 			    != 0) {
355 				printf("Can't overwrite \"%s\"\n", name);
356 				errno = EROFS;
357 				return -1;
358 			}
359 		}
360 	} else if (creating) {
361 		if (env_flags_validate_varaccess(name,
362 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
363 			printf("Can't create \"%s\"\n", name);
364 			errno = EROFS;
365 			return -1;
366 		}
367 	} else
368 		/* Nothing to do */
369 		return 0;
370 
371 	if (deleting || overwriting) {
372 		if (*++nxt == '\0') {
373 			*env = '\0';
374 		} else {
375 			for (;;) {
376 				*env = *nxt++;
377 				if ((*env == '\0') && (*nxt == '\0'))
378 					break;
379 				++env;
380 			}
381 		}
382 		*++env = '\0';
383 	}
384 
385 	/* Delete only ? */
386 	if (!value || !strlen(value))
387 		return 0;
388 
389 	/*
390 	 * Append new definition at the end
391 	 */
392 	for (env = environment.data; *env || *(env + 1); ++env);
393 	if (env > environment.data)
394 		++env;
395 	/*
396 	 * Overflow when:
397 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
398 	 */
399 	len = strlen (name) + 2;
400 	/* add '=' for first arg, ' ' for all others */
401 	len += strlen(value) + 1;
402 
403 	if (len > (&environment.data[ENV_SIZE] - env)) {
404 		fprintf (stderr,
405 			"Error: environment overflow, \"%s\" deleted\n",
406 			name);
407 		return -1;
408 	}
409 
410 	while ((*env = *name++) != '\0')
411 		env++;
412 	*env = '=';
413 	while ((*++env = *value++) != '\0')
414 		;
415 
416 	/* end is marked with double '\0' */
417 	*++env = '\0';
418 
419 	return 0;
420 }
421 
422 /*
423  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
424  * 0	  - OK
425  * EINVAL - need at least 1 argument
426  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
427  *	    modified or deleted
428  *
429  */
430 int fw_setenv(int argc, char *argv[])
431 {
432 	int i;
433 	size_t len;
434 	char *name;
435 	char *value = NULL;
436 
437 	if (argc < 2) {
438 		errno = EINVAL;
439 		return -1;
440 	}
441 
442 	if (fw_env_open()) {
443 		fprintf(stderr, "Error: environment not initialized\n");
444 		return -1;
445 	}
446 
447 	name = argv[1];
448 
449 	if (env_flags_validate_env_set_params(argc, argv) < 0)
450 		return 1;
451 
452 	len = 0;
453 	for (i = 2; i < argc; ++i) {
454 		char *val = argv[i];
455 		size_t val_len = strlen(val);
456 
457 		if (value)
458 			value[len - 1] = ' ';
459 		value = realloc(value, len + val_len + 1);
460 		if (!value) {
461 			fprintf(stderr,
462 				"Cannot malloc %zu bytes: %s\n",
463 				len, strerror(errno));
464 			return -1;
465 		}
466 
467 		memcpy(value + len, val, val_len);
468 		len += val_len;
469 		value[len++] = '\0';
470 	}
471 
472 	fw_env_write(name, value);
473 
474 	free(value);
475 
476 	return fw_env_close();
477 }
478 
479 /*
480  * Parse  a file  and configure the u-boot variables.
481  * The script file has a very simple format, as follows:
482  *
483  * Each line has a couple with name, value:
484  * <white spaces>variable_name<white spaces>variable_value
485  *
486  * Both variable_name and variable_value are interpreted as strings.
487  * Any character after <white spaces> and before ending \r\n is interpreted
488  * as variable's value (no comment allowed on these lines !)
489  *
490  * Comments are allowed if the first character in the line is #
491  *
492  * Returns -1 and sets errno error codes:
493  * 0	  - OK
494  * -1     - Error
495  */
496 int fw_parse_script(char *fname)
497 {
498 	FILE *fp;
499 	char dump[1024];	/* Maximum line length in the file */
500 	char *name;
501 	char *val;
502 	int lineno = 0;
503 	int len;
504 	int ret = 0;
505 
506 	if (fw_env_open()) {
507 		fprintf(stderr, "Error: environment not initialized\n");
508 		return -1;
509 	}
510 
511 	if (strcmp(fname, "-") == 0)
512 		fp = stdin;
513 	else {
514 		fp = fopen(fname, "r");
515 		if (fp == NULL) {
516 			fprintf(stderr, "I cannot open %s for reading\n",
517 				 fname);
518 			return -1;
519 		}
520 	}
521 
522 	while (fgets(dump, sizeof(dump), fp)) {
523 		lineno++;
524 		len = strlen(dump);
525 
526 		/*
527 		 * Read a whole line from the file. If the line is too long
528 		 * or is not terminated, reports an error and exit.
529 		 */
530 		if (dump[len - 1] != '\n') {
531 			fprintf(stderr,
532 			"Line %d not corrected terminated or too long\n",
533 				lineno);
534 			ret = -1;
535 			break;
536 		}
537 
538 		/* Drop ending line feed / carriage return */
539 		while (len > 0 && (dump[len - 1] == '\n' ||
540 				dump[len - 1] == '\r')) {
541 			dump[len - 1] = '\0';
542 			len--;
543 		}
544 
545 		/* Skip comment or empty lines */
546 		if ((len == 0) || dump[0] == '#')
547 			continue;
548 
549 		/*
550 		 * Search for variable's name,
551 		 * remove leading whitespaces
552 		 */
553 		name = fw_string_blank(dump, 1);
554 		if (!name)
555 			continue;
556 
557 		/* The first white space is the end of variable name */
558 		val = fw_string_blank(name, 0);
559 		len = strlen(name);
560 		if (val) {
561 			*val++ = '\0';
562 			if ((val - name) < len)
563 				val = fw_string_blank(val, 1);
564 			else
565 				val = NULL;
566 		}
567 
568 #ifdef DEBUG
569 		fprintf(stderr, "Setting %s : %s\n",
570 			name, val ? val : " removed");
571 #endif
572 
573 		if (env_flags_validate_type(name, val) < 0) {
574 			ret = -1;
575 			break;
576 		}
577 
578 		/*
579 		 * If there is an error setting a variable,
580 		 * try to save the environment and returns an error
581 		 */
582 		if (fw_env_write(name, val)) {
583 			fprintf(stderr,
584 			"fw_env_write returns with error : %s\n",
585 				strerror(errno));
586 			ret = -1;
587 			break;
588 		}
589 
590 	}
591 
592 	/* Close file if not stdin */
593 	if (strcmp(fname, "-") != 0)
594 		fclose(fp);
595 
596 	ret |= fw_env_close();
597 
598 	return ret;
599 
600 }
601 
602 /*
603  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
604  * 0	- block is good
605  * > 0	- block is bad
606  * < 0	- failed to test
607  */
608 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
609 {
610 	if (mtd_type == MTD_NANDFLASH) {
611 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
612 
613 		if (badblock < 0) {
614 			perror ("Cannot read bad block mark");
615 			return badblock;
616 		}
617 
618 		if (badblock) {
619 #ifdef DEBUG
620 			fprintf (stderr, "Bad block at 0x%llx, "
621 				 "skipping\n", *blockstart);
622 #endif
623 			return badblock;
624 		}
625 	}
626 
627 	return 0;
628 }
629 
630 /*
631  * Read data from flash at an offset into a provided buffer. On NAND it skips
632  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
633  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
634  */
635 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
636 			   off_t offset, uint8_t mtd_type)
637 {
638 	size_t blocklen;	/* erase / write length - one block on NAND,
639 				   0 on NOR */
640 	size_t processed = 0;	/* progress counter */
641 	size_t readlen = count;	/* current read length */
642 	off_t top_of_range;	/* end of the last block we may use */
643 	off_t block_seek;	/* offset inside the current block to the start
644 				   of the data */
645 	loff_t blockstart;	/* running start of the current block -
646 				   MEMGETBADBLOCK needs 64 bits */
647 	int rc;
648 
649 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
650 
651 	/* Offset inside a block */
652 	block_seek = offset - blockstart;
653 
654 	if (mtd_type == MTD_NANDFLASH) {
655 		/*
656 		 * NAND: calculate which blocks we are reading. We have
657 		 * to read one block at a time to skip bad blocks.
658 		 */
659 		blocklen = DEVESIZE (dev);
660 
661 		/*
662 		 * To calculate the top of the range, we have to use the
663 		 * global DEVOFFSET (dev), which can be different from offset
664 		 */
665 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
666 				ENVSECTORS (dev)) * blocklen;
667 
668 		/* Limit to one block for the first read */
669 		if (readlen > blocklen - block_seek)
670 			readlen = blocklen - block_seek;
671 	} else {
672 		blocklen = 0;
673 		top_of_range = offset + count;
674 	}
675 
676 	/* This only runs once on NOR flash */
677 	while (processed < count) {
678 		rc = flash_bad_block (fd, mtd_type, &blockstart);
679 		if (rc < 0)		/* block test failed */
680 			return -1;
681 
682 		if (blockstart + block_seek + readlen > top_of_range) {
683 			/* End of range is reached */
684 			fprintf (stderr,
685 				 "Too few good blocks within range\n");
686 			return -1;
687 		}
688 
689 		if (rc) {		/* block is bad */
690 			blockstart += blocklen;
691 			continue;
692 		}
693 
694 		/*
695 		 * If a block is bad, we retry in the next block at the same
696 		 * offset - see common/env_nand.c::writeenv()
697 		 */
698 		lseek (fd, blockstart + block_seek, SEEK_SET);
699 
700 		rc = read (fd, buf + processed, readlen);
701 		if (rc != readlen) {
702 			fprintf (stderr, "Read error on %s: %s\n",
703 				 DEVNAME (dev), strerror (errno));
704 			return -1;
705 		}
706 #ifdef DEBUG
707 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
708 			 rc, blockstart + block_seek, DEVNAME(dev));
709 #endif
710 		processed += readlen;
711 		readlen = min (blocklen, count - processed);
712 		block_seek = 0;
713 		blockstart += blocklen;
714 	}
715 
716 	return processed;
717 }
718 
719 /*
720  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
721  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
722  * erase and write the whole data at once.
723  */
724 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
725 			    off_t offset, uint8_t mtd_type)
726 {
727 	void *data;
728 	struct erase_info_user erase;
729 	size_t blocklen;	/* length of NAND block / NOR erase sector */
730 	size_t erase_len;	/* whole area that can be erased - may include
731 				   bad blocks */
732 	size_t erasesize;	/* erase / write length - one block on NAND,
733 				   whole area on NOR */
734 	size_t processed = 0;	/* progress counter */
735 	size_t write_total;	/* total size to actually write - excluding
736 				   bad blocks */
737 	off_t erase_offset;	/* offset to the first erase block (aligned)
738 				   below offset */
739 	off_t block_seek;	/* offset inside the erase block to the start
740 				   of the data */
741 	off_t top_of_range;	/* end of the last block we may use */
742 	loff_t blockstart;	/* running start of the current block -
743 				   MEMGETBADBLOCK needs 64 bits */
744 	int rc;
745 
746 	blocklen = DEVESIZE (dev);
747 
748 	top_of_range = ((DEVOFFSET(dev) / blocklen) +
749 					ENVSECTORS (dev)) * blocklen;
750 
751 	erase_offset = (offset / blocklen) * blocklen;
752 
753 	/* Maximum area we may use */
754 	erase_len = top_of_range - erase_offset;
755 
756 	blockstart = erase_offset;
757 	/* Offset inside a block */
758 	block_seek = offset - erase_offset;
759 
760 	/*
761 	 * Data size we actually have to write: from the start of the block
762 	 * to the start of the data, then count bytes of data, and to the
763 	 * end of the block
764 	 */
765 	write_total = ((block_seek + count + blocklen - 1) /
766 						blocklen) * blocklen;
767 
768 	/*
769 	 * Support data anywhere within erase sectors: read out the complete
770 	 * area to be erased, replace the environment image, write the whole
771 	 * block back again.
772 	 */
773 	if (write_total > count) {
774 		data = malloc (erase_len);
775 		if (!data) {
776 			fprintf (stderr,
777 				 "Cannot malloc %zu bytes: %s\n",
778 				 erase_len, strerror (errno));
779 			return -1;
780 		}
781 
782 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
783 				     mtd_type);
784 		if (write_total != rc)
785 			return -1;
786 
787 #ifdef DEBUG
788 		fprintf(stderr, "Preserving data ");
789 		if (block_seek != 0)
790 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
791 		if (block_seek + count != write_total) {
792 			if (block_seek != 0)
793 				fprintf(stderr, " and ");
794 			fprintf(stderr, "0x%lx - 0x%x",
795 				block_seek + count, write_total - 1);
796 		}
797 		fprintf(stderr, "\n");
798 #endif
799 		/* Overwrite the old environment */
800 		memcpy (data + block_seek, buf, count);
801 	} else {
802 		/*
803 		 * We get here, iff offset is block-aligned and count is a
804 		 * multiple of blocklen - see write_total calculation above
805 		 */
806 		data = buf;
807 	}
808 
809 	if (mtd_type == MTD_NANDFLASH) {
810 		/*
811 		 * NAND: calculate which blocks we are writing. We have
812 		 * to write one block at a time to skip bad blocks.
813 		 */
814 		erasesize = blocklen;
815 	} else {
816 		erasesize = erase_len;
817 	}
818 
819 	erase.length = erasesize;
820 
821 	/* This only runs once on NOR flash and SPI-dataflash */
822 	while (processed < write_total) {
823 		rc = flash_bad_block (fd, mtd_type, &blockstart);
824 		if (rc < 0)		/* block test failed */
825 			return rc;
826 
827 		if (blockstart + erasesize > top_of_range) {
828 			fprintf (stderr, "End of range reached, aborting\n");
829 			return -1;
830 		}
831 
832 		if (rc) {		/* block is bad */
833 			blockstart += blocklen;
834 			continue;
835 		}
836 
837 		erase.start = blockstart;
838 		ioctl (fd, MEMUNLOCK, &erase);
839 
840 		/* Dataflash does not need an explicit erase cycle */
841 		if (mtd_type != MTD_DATAFLASH)
842 			if (ioctl (fd, MEMERASE, &erase) != 0) {
843 				fprintf (stderr, "MTD erase error on %s: %s\n",
844 					 DEVNAME (dev),
845 					 strerror (errno));
846 				return -1;
847 			}
848 
849 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
850 			fprintf (stderr,
851 				 "Seek error on %s: %s\n",
852 				 DEVNAME (dev), strerror (errno));
853 			return -1;
854 		}
855 
856 #ifdef DEBUG
857 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
858 			blockstart);
859 #endif
860 		if (write (fd, data + processed, erasesize) != erasesize) {
861 			fprintf (stderr, "Write error on %s: %s\n",
862 				 DEVNAME (dev), strerror (errno));
863 			return -1;
864 		}
865 
866 		ioctl (fd, MEMLOCK, &erase);
867 
868 		processed  += blocklen;
869 		block_seek = 0;
870 		blockstart += blocklen;
871 	}
872 
873 	if (write_total > count)
874 		free (data);
875 
876 	return processed;
877 }
878 
879 /*
880  * Set obsolete flag at offset - NOR flash only
881  */
882 static int flash_flag_obsolete (int dev, int fd, off_t offset)
883 {
884 	int rc;
885 	struct erase_info_user erase;
886 
887 	erase.start  = DEVOFFSET (dev);
888 	erase.length = DEVESIZE (dev);
889 	/* This relies on the fact, that obsolete_flag == 0 */
890 	rc = lseek (fd, offset, SEEK_SET);
891 	if (rc < 0) {
892 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
893 			 DEVNAME (dev));
894 		return rc;
895 	}
896 	ioctl (fd, MEMUNLOCK, &erase);
897 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
898 	ioctl (fd, MEMLOCK, &erase);
899 	if (rc < 0)
900 		perror ("Could not set obsolete flag");
901 
902 	return rc;
903 }
904 
905 static int flash_write (int fd_current, int fd_target, int dev_target)
906 {
907 	int rc;
908 
909 	switch (environment.flag_scheme) {
910 	case FLAG_NONE:
911 		break;
912 	case FLAG_INCREMENTAL:
913 		(*environment.flags)++;
914 		break;
915 	case FLAG_BOOLEAN:
916 		*environment.flags = active_flag;
917 		break;
918 	default:
919 		fprintf (stderr, "Unimplemented flash scheme %u \n",
920 			 environment.flag_scheme);
921 		return -1;
922 	}
923 
924 #ifdef DEBUG
925 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
926 		DEVOFFSET (dev_target), DEVNAME (dev_target));
927 #endif
928 	rc = flash_write_buf(dev_target, fd_target, environment.image,
929 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
930 			      DEVTYPE(dev_target));
931 	if (rc < 0)
932 		return rc;
933 
934 	if (environment.flag_scheme == FLAG_BOOLEAN) {
935 		/* Have to set obsolete flag */
936 		off_t offset = DEVOFFSET (dev_current) +
937 			offsetof (struct env_image_redundant, flags);
938 #ifdef DEBUG
939 		fprintf(stderr,
940 			"Setting obsolete flag in environment at 0x%lx on %s\n",
941 			DEVOFFSET (dev_current), DEVNAME (dev_current));
942 #endif
943 		flash_flag_obsolete (dev_current, fd_current, offset);
944 	}
945 
946 	return 0;
947 }
948 
949 static int flash_read (int fd)
950 {
951 	struct mtd_info_user mtdinfo;
952 	int rc;
953 
954 	rc = ioctl (fd, MEMGETINFO, &mtdinfo);
955 	if (rc < 0) {
956 		perror ("Cannot get MTD information");
957 		return -1;
958 	}
959 
960 	if (mtdinfo.type != MTD_NORFLASH &&
961 	    mtdinfo.type != MTD_NANDFLASH &&
962 	    mtdinfo.type != MTD_DATAFLASH) {
963 		fprintf (stderr, "Unsupported flash type %u\n", mtdinfo.type);
964 		return -1;
965 	}
966 
967 	DEVTYPE(dev_current) = mtdinfo.type;
968 
969 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
970 			     DEVOFFSET (dev_current), mtdinfo.type);
971 
972 	return (rc != CUR_ENVSIZE) ? -1 : 0;
973 }
974 
975 static int flash_io (int mode)
976 {
977 	int fd_current, fd_target, rc, dev_target;
978 
979 	/* dev_current: fd_current, erase_current */
980 	fd_current = open (DEVNAME (dev_current), mode);
981 	if (fd_current < 0) {
982 		fprintf (stderr,
983 			 "Can't open %s: %s\n",
984 			 DEVNAME (dev_current), strerror (errno));
985 		return -1;
986 	}
987 
988 	if (mode == O_RDWR) {
989 		if (HaveRedundEnv) {
990 			/* switch to next partition for writing */
991 			dev_target = !dev_current;
992 			/* dev_target: fd_target, erase_target */
993 			fd_target = open (DEVNAME (dev_target), mode);
994 			if (fd_target < 0) {
995 				fprintf (stderr,
996 					 "Can't open %s: %s\n",
997 					 DEVNAME (dev_target),
998 					 strerror (errno));
999 				rc = -1;
1000 				goto exit;
1001 			}
1002 		} else {
1003 			dev_target = dev_current;
1004 			fd_target = fd_current;
1005 		}
1006 
1007 		rc = flash_write (fd_current, fd_target, dev_target);
1008 
1009 		if (HaveRedundEnv) {
1010 			if (close (fd_target)) {
1011 				fprintf (stderr,
1012 					"I/O error on %s: %s\n",
1013 					DEVNAME (dev_target),
1014 					strerror (errno));
1015 				rc = -1;
1016 			}
1017 		}
1018 	} else {
1019 		rc = flash_read (fd_current);
1020 	}
1021 
1022 exit:
1023 	if (close (fd_current)) {
1024 		fprintf (stderr,
1025 			 "I/O error on %s: %s\n",
1026 			 DEVNAME (dev_current), strerror (errno));
1027 		return -1;
1028 	}
1029 
1030 	return rc;
1031 }
1032 
1033 /*
1034  * s1 is either a simple 'name', or a 'name=value' pair.
1035  * s2 is a 'name=value' pair.
1036  * If the names match, return the value of s2, else NULL.
1037  */
1038 
1039 static char *envmatch (char * s1, char * s2)
1040 {
1041 	if (s1 == NULL || s2 == NULL)
1042 		return NULL;
1043 
1044 	while (*s1 == *s2++)
1045 		if (*s1++ == '=')
1046 			return s2;
1047 	if (*s1 == '\0' && *(s2 - 1) == '=')
1048 		return s2;
1049 	return NULL;
1050 }
1051 
1052 /*
1053  * Prevent confusion if running from erased flash memory
1054  */
1055 int fw_env_open(void)
1056 {
1057 	int crc0, crc0_ok;
1058 	unsigned char flag0;
1059 	void *addr0;
1060 
1061 	int crc1, crc1_ok;
1062 	unsigned char flag1;
1063 	void *addr1;
1064 
1065 	struct env_image_single *single;
1066 	struct env_image_redundant *redundant;
1067 
1068 	if (parse_config ())		/* should fill envdevices */
1069 		return -1;
1070 
1071 	addr0 = calloc(1, CUR_ENVSIZE);
1072 	if (addr0 == NULL) {
1073 		fprintf(stderr,
1074 			"Not enough memory for environment (%ld bytes)\n",
1075 			CUR_ENVSIZE);
1076 		return -1;
1077 	}
1078 
1079 	/* read environment from FLASH to local buffer */
1080 	environment.image = addr0;
1081 
1082 	if (HaveRedundEnv) {
1083 		redundant = addr0;
1084 		environment.crc		= &redundant->crc;
1085 		environment.flags	= &redundant->flags;
1086 		environment.data	= redundant->data;
1087 	} else {
1088 		single = addr0;
1089 		environment.crc		= &single->crc;
1090 		environment.flags	= NULL;
1091 		environment.data	= single->data;
1092 	}
1093 
1094 	dev_current = 0;
1095 	if (flash_io (O_RDONLY))
1096 		return -1;
1097 
1098 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1099 	crc0_ok = (crc0 == *environment.crc);
1100 	if (!HaveRedundEnv) {
1101 		if (!crc0_ok) {
1102 			fprintf (stderr,
1103 				"Warning: Bad CRC, using default environment\n");
1104 			memcpy(environment.data, default_environment, sizeof default_environment);
1105 		}
1106 	} else {
1107 		flag0 = *environment.flags;
1108 
1109 		dev_current = 1;
1110 		addr1 = calloc(1, CUR_ENVSIZE);
1111 		if (addr1 == NULL) {
1112 			fprintf(stderr,
1113 				"Not enough memory for environment (%ld bytes)\n",
1114 				CUR_ENVSIZE);
1115 			return -1;
1116 		}
1117 		redundant = addr1;
1118 
1119 		/*
1120 		 * have to set environment.image for flash_read(), careful -
1121 		 * other pointers in environment still point inside addr0
1122 		 */
1123 		environment.image = addr1;
1124 		if (flash_io (O_RDONLY))
1125 			return -1;
1126 
1127 		/* Check flag scheme compatibility */
1128 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1129 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1130 			environment.flag_scheme = FLAG_BOOLEAN;
1131 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1132 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1133 			environment.flag_scheme = FLAG_INCREMENTAL;
1134 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1135 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1136 			environment.flag_scheme = FLAG_BOOLEAN;
1137 		} else {
1138 			fprintf (stderr, "Incompatible flash types!\n");
1139 			return -1;
1140 		}
1141 
1142 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1143 		crc1_ok = (crc1 == redundant->crc);
1144 		flag1 = redundant->flags;
1145 
1146 		if (crc0_ok && !crc1_ok) {
1147 			dev_current = 0;
1148 		} else if (!crc0_ok && crc1_ok) {
1149 			dev_current = 1;
1150 		} else if (!crc0_ok && !crc1_ok) {
1151 			fprintf (stderr,
1152 				"Warning: Bad CRC, using default environment\n");
1153 			memcpy (environment.data, default_environment,
1154 				sizeof default_environment);
1155 			dev_current = 0;
1156 		} else {
1157 			switch (environment.flag_scheme) {
1158 			case FLAG_BOOLEAN:
1159 				if (flag0 == active_flag &&
1160 				    flag1 == obsolete_flag) {
1161 					dev_current = 0;
1162 				} else if (flag0 == obsolete_flag &&
1163 					   flag1 == active_flag) {
1164 					dev_current = 1;
1165 				} else if (flag0 == flag1) {
1166 					dev_current = 0;
1167 				} else if (flag0 == 0xFF) {
1168 					dev_current = 0;
1169 				} else if (flag1 == 0xFF) {
1170 					dev_current = 1;
1171 				} else {
1172 					dev_current = 0;
1173 				}
1174 				break;
1175 			case FLAG_INCREMENTAL:
1176 				if (flag0 == 255 && flag1 == 0)
1177 					dev_current = 1;
1178 				else if ((flag1 == 255 && flag0 == 0) ||
1179 					 flag0 >= flag1)
1180 					dev_current = 0;
1181 				else /* flag1 > flag0 */
1182 					dev_current = 1;
1183 				break;
1184 			default:
1185 				fprintf (stderr, "Unknown flag scheme %u \n",
1186 					 environment.flag_scheme);
1187 				return -1;
1188 			}
1189 		}
1190 
1191 		/*
1192 		 * If we are reading, we don't need the flag and the CRC any
1193 		 * more, if we are writing, we will re-calculate CRC and update
1194 		 * flags before writing out
1195 		 */
1196 		if (dev_current) {
1197 			environment.image	= addr1;
1198 			environment.crc		= &redundant->crc;
1199 			environment.flags	= &redundant->flags;
1200 			environment.data	= redundant->data;
1201 			free (addr0);
1202 		} else {
1203 			environment.image	= addr0;
1204 			/* Other pointers are already set */
1205 			free (addr1);
1206 		}
1207 #ifdef DEBUG
1208 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1209 #endif
1210 	}
1211 	return 0;
1212 }
1213 
1214 
1215 static int parse_config ()
1216 {
1217 	struct stat st;
1218 
1219 #if defined(CONFIG_FILE)
1220 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1221 	if (get_config (CONFIG_FILE)) {
1222 		fprintf (stderr,
1223 			"Cannot parse config file: %s\n", strerror (errno));
1224 		return -1;
1225 	}
1226 #else
1227 	strcpy (DEVNAME (0), DEVICE1_NAME);
1228 	DEVOFFSET (0) = DEVICE1_OFFSET;
1229 	ENVSIZE (0) = ENV1_SIZE;
1230 	/* Default values are: erase-size=env-size, #sectors=1 */
1231 	DEVESIZE (0) = ENVSIZE (0);
1232 	ENVSECTORS (0) = 1;
1233 #ifdef DEVICE1_ESIZE
1234 	DEVESIZE (0) = DEVICE1_ESIZE;
1235 #endif
1236 #ifdef DEVICE1_ENVSECTORS
1237 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1238 #endif
1239 
1240 #ifdef HAVE_REDUND
1241 	strcpy (DEVNAME (1), DEVICE2_NAME);
1242 	DEVOFFSET (1) = DEVICE2_OFFSET;
1243 	ENVSIZE (1) = ENV2_SIZE;
1244 	/* Default values are: erase-size=env-size, #sectors=1 */
1245 	DEVESIZE (1) = ENVSIZE (1);
1246 	ENVSECTORS (1) = 1;
1247 #ifdef DEVICE2_ESIZE
1248 	DEVESIZE (1) = DEVICE2_ESIZE;
1249 #endif
1250 #ifdef DEVICE2_ENVSECTORS
1251 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1252 #endif
1253 	HaveRedundEnv = 1;
1254 #endif
1255 #endif
1256 	if (stat (DEVNAME (0), &st)) {
1257 		fprintf (stderr,
1258 			"Cannot access MTD device %s: %s\n",
1259 			DEVNAME (0), strerror (errno));
1260 		return -1;
1261 	}
1262 
1263 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1264 		fprintf (stderr,
1265 			"Cannot access MTD device %s: %s\n",
1266 			DEVNAME (1), strerror (errno));
1267 		return -1;
1268 	}
1269 	return 0;
1270 }
1271 
1272 #if defined(CONFIG_FILE)
1273 static int get_config (char *fname)
1274 {
1275 	FILE *fp;
1276 	int i = 0;
1277 	int rc;
1278 	char dump[128];
1279 
1280 	fp = fopen (fname, "r");
1281 	if (fp == NULL)
1282 		return -1;
1283 
1284 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1285 		/* Skip incomplete conversions and comment strings */
1286 		if (dump[0] == '#')
1287 			continue;
1288 
1289 		rc = sscanf (dump, "%s %lx %lx %lx %lx",
1290 			     DEVNAME (i),
1291 			     &DEVOFFSET (i),
1292 			     &ENVSIZE (i),
1293 			     &DEVESIZE (i),
1294 			     &ENVSECTORS (i));
1295 
1296 		if (rc < 3)
1297 			continue;
1298 
1299 		if (rc < 4)
1300 			/* Assume the erase size is the same as the env-size */
1301 			DEVESIZE(i) = ENVSIZE(i);
1302 
1303 		if (rc < 5)
1304 			/* Default - 1 sector */
1305 			ENVSECTORS (i) = 1;
1306 
1307 		i++;
1308 	}
1309 	fclose (fp);
1310 
1311 	HaveRedundEnv = i - 1;
1312 	if (!i) {			/* No valid entries found */
1313 		errno = EINVAL;
1314 		return -1;
1315 	} else
1316 		return 0;
1317 }
1318 #endif
1319