xref: /openbmc/u-boot/tools/env/fw_env.c (revision 214cc905defa58b2beb57033ebc6e66a2a90d769)
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/stringify.h>
18 #include <ctype.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <stddef.h>
22 #include <string.h>
23 #include <sys/types.h>
24 #include <sys/ioctl.h>
25 #include <sys/stat.h>
26 #include <unistd.h>
27 
28 #ifdef MTD_OLD
29 # include <stdint.h>
30 # include <linux/mtd/mtd.h>
31 #else
32 # define  __user	/* nothing */
33 # include <mtd/mtd-user.h>
34 #endif
35 
36 #include "fw_env.h"
37 
38 #define DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
39 
40 #define min(x, y) ({				\
41 	typeof(x) _min1 = (x);			\
42 	typeof(y) _min2 = (y);			\
43 	(void) (&_min1 == &_min2);		\
44 	_min1 < _min2 ? _min1 : _min2; })
45 
46 struct envdev_s {
47 	const char *devname;		/* Device name */
48 	ulong devoff;			/* Device offset */
49 	ulong env_size;			/* environment size */
50 	ulong erase_size;		/* device erase size */
51 	ulong env_sectors;		/* number of environment sectors */
52 	uint8_t mtd_type;		/* type of the MTD device */
53 };
54 
55 static struct envdev_s envdevices[2] =
56 {
57 	{
58 		.mtd_type = MTD_ABSENT,
59 	}, {
60 		.mtd_type = MTD_ABSENT,
61 	},
62 };
63 static int dev_current;
64 
65 #define DEVNAME(i)    envdevices[(i)].devname
66 #define DEVOFFSET(i)  envdevices[(i)].devoff
67 #define ENVSIZE(i)    envdevices[(i)].env_size
68 #define DEVESIZE(i)   envdevices[(i)].erase_size
69 #define ENVSECTORS(i) envdevices[(i)].env_sectors
70 #define DEVTYPE(i)    envdevices[(i)].mtd_type
71 
72 #define CUR_ENVSIZE ENVSIZE(dev_current)
73 
74 #define ENV_SIZE      getenvsize()
75 
76 struct env_image_single {
77 	uint32_t	crc;	/* CRC32 over data bytes    */
78 	char		data[];
79 };
80 
81 struct env_image_redundant {
82 	uint32_t	crc;	/* CRC32 over data bytes    */
83 	unsigned char	flags;	/* active or obsolete */
84 	char		data[];
85 };
86 
87 enum flag_scheme {
88 	FLAG_NONE,
89 	FLAG_BOOLEAN,
90 	FLAG_INCREMENTAL,
91 };
92 
93 struct environment {
94 	void			*image;
95 	uint32_t		*crc;
96 	unsigned char		*flags;
97 	char			*data;
98 	enum flag_scheme	flag_scheme;
99 };
100 
101 static struct environment environment = {
102 	.flag_scheme = FLAG_NONE,
103 };
104 
105 static int env_aes_cbc_crypt(char *data, const int enc);
106 
107 static int HaveRedundEnv = 0;
108 
109 static unsigned char active_flag = 1;
110 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
111 static unsigned char obsolete_flag = 0;
112 
113 #define DEFAULT_ENV_INSTANCE_STATIC
114 #include <env_default.h>
115 
116 static int flash_io (int mode);
117 static char *envmatch (char * s1, char * s2);
118 static int parse_config (void);
119 
120 #if defined(CONFIG_FILE)
121 static int get_config (char *);
122 #endif
123 static inline ulong getenvsize (void)
124 {
125 	ulong rc = CUR_ENVSIZE - sizeof(uint32_t);
126 
127 	if (HaveRedundEnv)
128 		rc -= sizeof (char);
129 
130 	if (common_args.aes_flag)
131 		rc &= ~(AES_KEY_LENGTH - 1);
132 
133 	return rc;
134 }
135 
136 static char *skip_chars(char *s)
137 {
138 	for (; *s != '\0'; s++) {
139 		if (isblank(*s))
140 			return s;
141 	}
142 	return NULL;
143 }
144 
145 static char *skip_blanks(char *s)
146 {
147 	for (; *s != '\0'; s++) {
148 		if (!isblank(*s))
149 			return s;
150 	}
151 	return NULL;
152 }
153 
154 /*
155  * Search the environment for a variable.
156  * Return the value, if found, or NULL, if not found.
157  */
158 char *fw_getenv (char *name)
159 {
160 	char *env, *nxt;
161 
162 	for (env = environment.data; *env; env = nxt + 1) {
163 		char *val;
164 
165 		for (nxt = env; *nxt; ++nxt) {
166 			if (nxt >= &environment.data[ENV_SIZE]) {
167 				fprintf (stderr, "## Error: "
168 					"environment not terminated\n");
169 				return NULL;
170 			}
171 		}
172 		val = envmatch (name, env);
173 		if (!val)
174 			continue;
175 		return val;
176 	}
177 	return NULL;
178 }
179 
180 /*
181  * Search the default environment for a variable.
182  * Return the value, if found, or NULL, if not found.
183  */
184 char *fw_getdefenv(char *name)
185 {
186 	char *env, *nxt;
187 
188 	for (env = default_environment; *env; env = nxt + 1) {
189 		char *val;
190 
191 		for (nxt = env; *nxt; ++nxt) {
192 			if (nxt >= &default_environment[ENV_SIZE]) {
193 				fprintf(stderr, "## Error: "
194 					"default environment not terminated\n");
195 				return NULL;
196 			}
197 		}
198 		val = envmatch(name, env);
199 		if (!val)
200 			continue;
201 		return val;
202 	}
203 	return NULL;
204 }
205 
206 int parse_aes_key(char *key, uint8_t *bin_key)
207 {
208 	char tmp[5] = { '0', 'x', 0, 0, 0 };
209 	unsigned long ul;
210 	int i;
211 
212 	if (strnlen(key, 64) != 32) {
213 		fprintf(stderr,
214 			"## Error: '-a' option requires 16-byte AES key\n");
215 		return -1;
216 	}
217 
218 	for (i = 0; i < 16; i++) {
219 		tmp[2] = key[0];
220 		tmp[3] = key[1];
221 		errno = 0;
222 		ul = strtoul(tmp, NULL, 16);
223 		if (errno) {
224 			fprintf(stderr,
225 				"## Error: '-a' option requires valid AES key\n");
226 			return -1;
227 		}
228 		bin_key[i] = ul & 0xff;
229 		key += 2;
230 	}
231 	return 0;
232 }
233 
234 /*
235  * Print the current definition of one, or more, or all
236  * environment variables
237  */
238 int fw_printenv (int argc, char *argv[])
239 {
240 	char *env, *nxt;
241 	int i, rc = 0;
242 
243 	if (fw_env_open())
244 		return -1;
245 
246 	if (argc == 0) {		/* Print all env variables  */
247 		for (env = environment.data; *env; env = nxt + 1) {
248 			for (nxt = env; *nxt; ++nxt) {
249 				if (nxt >= &environment.data[ENV_SIZE]) {
250 					fprintf (stderr, "## Error: "
251 						"environment not terminated\n");
252 					return -1;
253 				}
254 			}
255 
256 			printf ("%s\n", env);
257 		}
258 		return 0;
259 	}
260 
261 	if (printenv_args.name_suppress && argc != 1) {
262 		fprintf(stderr,
263 			"## Error: `-n' option requires exactly one argument\n");
264 		return -1;
265 	}
266 
267 	for (i = 0; i < argc; ++i) {	/* print single env variables   */
268 		char *name = argv[i];
269 		char *val = NULL;
270 
271 		for (env = environment.data; *env; env = nxt + 1) {
272 
273 			for (nxt = env; *nxt; ++nxt) {
274 				if (nxt >= &environment.data[ENV_SIZE]) {
275 					fprintf (stderr, "## Error: "
276 						"environment not terminated\n");
277 					return -1;
278 				}
279 			}
280 			val = envmatch (name, env);
281 			if (val) {
282 				if (!printenv_args.name_suppress) {
283 					fputs (name, stdout);
284 					putc ('=', stdout);
285 				}
286 				puts (val);
287 				break;
288 			}
289 		}
290 		if (!val) {
291 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
292 			rc = -1;
293 		}
294 	}
295 
296 	return rc;
297 }
298 
299 int fw_env_close(void)
300 {
301 	int ret;
302 	if (common_args.aes_flag) {
303 		ret = env_aes_cbc_crypt(environment.data, 1);
304 		if (ret) {
305 			fprintf(stderr,
306 				"Error: can't encrypt env for flash\n");
307 			return ret;
308 		}
309 	}
310 
311 	/*
312 	 * Update CRC
313 	 */
314 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
315 
316 	/* write environment back to flash */
317 	if (flash_io(O_RDWR)) {
318 		fprintf(stderr,
319 			"Error: can't write fw_env to flash\n");
320 			return -1;
321 	}
322 
323 	return 0;
324 }
325 
326 
327 /*
328  * Set/Clear a single variable in the environment.
329  * This is called in sequence to update the environment
330  * in RAM without updating the copy in flash after each set
331  */
332 int fw_env_write(char *name, char *value)
333 {
334 	int len;
335 	char *env, *nxt;
336 	char *oldval = NULL;
337 	int deleting, creating, overwriting;
338 
339 	/*
340 	 * search if variable with this name already exists
341 	 */
342 	for (nxt = env = environment.data; *env; env = nxt + 1) {
343 		for (nxt = env; *nxt; ++nxt) {
344 			if (nxt >= &environment.data[ENV_SIZE]) {
345 				fprintf(stderr, "## Error: "
346 					"environment not terminated\n");
347 				errno = EINVAL;
348 				return -1;
349 			}
350 		}
351 		if ((oldval = envmatch (name, env)) != NULL)
352 			break;
353 	}
354 
355 	deleting = (oldval && !(value && strlen(value)));
356 	creating = (!oldval && (value && strlen(value)));
357 	overwriting = (oldval && (value && strlen(value)));
358 
359 	/* check for permission */
360 	if (deleting) {
361 		if (env_flags_validate_varaccess(name,
362 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
363 			printf("Can't delete \"%s\"\n", name);
364 			errno = EROFS;
365 			return -1;
366 		}
367 	} else if (overwriting) {
368 		if (env_flags_validate_varaccess(name,
369 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
370 			printf("Can't overwrite \"%s\"\n", name);
371 			errno = EROFS;
372 			return -1;
373 		} else if (env_flags_validate_varaccess(name,
374 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
375 			const char *defval = fw_getdefenv(name);
376 
377 			if (defval == NULL)
378 				defval = "";
379 			if (strcmp(oldval, defval)
380 			    != 0) {
381 				printf("Can't overwrite \"%s\"\n", name);
382 				errno = EROFS;
383 				return -1;
384 			}
385 		}
386 	} else if (creating) {
387 		if (env_flags_validate_varaccess(name,
388 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
389 			printf("Can't create \"%s\"\n", name);
390 			errno = EROFS;
391 			return -1;
392 		}
393 	} else
394 		/* Nothing to do */
395 		return 0;
396 
397 	if (deleting || overwriting) {
398 		if (*++nxt == '\0') {
399 			*env = '\0';
400 		} else {
401 			for (;;) {
402 				*env = *nxt++;
403 				if ((*env == '\0') && (*nxt == '\0'))
404 					break;
405 				++env;
406 			}
407 		}
408 		*++env = '\0';
409 	}
410 
411 	/* Delete only ? */
412 	if (!value || !strlen(value))
413 		return 0;
414 
415 	/*
416 	 * Append new definition at the end
417 	 */
418 	for (env = environment.data; *env || *(env + 1); ++env);
419 	if (env > environment.data)
420 		++env;
421 	/*
422 	 * Overflow when:
423 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
424 	 */
425 	len = strlen (name) + 2;
426 	/* add '=' for first arg, ' ' for all others */
427 	len += strlen(value) + 1;
428 
429 	if (len > (&environment.data[ENV_SIZE] - env)) {
430 		fprintf (stderr,
431 			"Error: environment overflow, \"%s\" deleted\n",
432 			name);
433 		return -1;
434 	}
435 
436 	while ((*env = *name++) != '\0')
437 		env++;
438 	*env = '=';
439 	while ((*++env = *value++) != '\0')
440 		;
441 
442 	/* end is marked with double '\0' */
443 	*++env = '\0';
444 
445 	return 0;
446 }
447 
448 /*
449  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
450  * 0	  - OK
451  * EINVAL - need at least 1 argument
452  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
453  *	    modified or deleted
454  *
455  */
456 int fw_setenv(int argc, char *argv[])
457 {
458 	int i;
459 	size_t len;
460 	char *name, **valv;
461 	char *value = NULL;
462 	int valc;
463 
464 	if (argc < 1) {
465 		fprintf(stderr, "## Error: variable name missing\n");
466 		errno = EINVAL;
467 		return -1;
468 	}
469 
470 	if (fw_env_open()) {
471 		fprintf(stderr, "Error: environment not initialized\n");
472 		return -1;
473 	}
474 
475 	name = argv[0];
476 	valv = argv + 1;
477 	valc = argc - 1;
478 
479 	if (env_flags_validate_env_set_params(name, valv, valc) < 0)
480 		return 1;
481 
482 	len = 0;
483 	for (i = 0; i < valc; ++i) {
484 		char *val = valv[i];
485 		size_t val_len = strlen(val);
486 
487 		if (value)
488 			value[len - 1] = ' ';
489 		value = realloc(value, len + val_len + 1);
490 		if (!value) {
491 			fprintf(stderr,
492 				"Cannot malloc %zu bytes: %s\n",
493 				len, strerror(errno));
494 			return -1;
495 		}
496 
497 		memcpy(value + len, val, val_len);
498 		len += val_len;
499 		value[len++] = '\0';
500 	}
501 
502 	fw_env_write(name, value);
503 
504 	free(value);
505 
506 	return fw_env_close();
507 }
508 
509 /*
510  * Parse  a file  and configure the u-boot variables.
511  * The script file has a very simple format, as follows:
512  *
513  * Each line has a couple with name, value:
514  * <white spaces>variable_name<white spaces>variable_value
515  *
516  * Both variable_name and variable_value are interpreted as strings.
517  * Any character after <white spaces> and before ending \r\n is interpreted
518  * as variable's value (no comment allowed on these lines !)
519  *
520  * Comments are allowed if the first character in the line is #
521  *
522  * Returns -1 and sets errno error codes:
523  * 0	  - OK
524  * -1     - Error
525  */
526 int fw_parse_script(char *fname)
527 {
528 	FILE *fp;
529 	char dump[1024];	/* Maximum line length in the file */
530 	char *name;
531 	char *val;
532 	int lineno = 0;
533 	int len;
534 	int ret = 0;
535 
536 	if (fw_env_open()) {
537 		fprintf(stderr, "Error: environment not initialized\n");
538 		return -1;
539 	}
540 
541 	if (strcmp(fname, "-") == 0)
542 		fp = stdin;
543 	else {
544 		fp = fopen(fname, "r");
545 		if (fp == NULL) {
546 			fprintf(stderr, "I cannot open %s for reading\n",
547 				 fname);
548 			return -1;
549 		}
550 	}
551 
552 	while (fgets(dump, sizeof(dump), fp)) {
553 		lineno++;
554 		len = strlen(dump);
555 
556 		/*
557 		 * Read a whole line from the file. If the line is too long
558 		 * or is not terminated, reports an error and exit.
559 		 */
560 		if (dump[len - 1] != '\n') {
561 			fprintf(stderr,
562 			"Line %d not corrected terminated or too long\n",
563 				lineno);
564 			ret = -1;
565 			break;
566 		}
567 
568 		/* Drop ending line feed / carriage return */
569 		dump[--len] = '\0';
570 		if (len && dump[len - 1] == '\r')
571 			dump[--len] = '\0';
572 
573 		/* Skip comment or empty lines */
574 		if (len == 0 || dump[0] == '#')
575 			continue;
576 
577 		/*
578 		 * Search for variable's name,
579 		 * remove leading whitespaces
580 		 */
581 		name = skip_blanks(dump);
582 		if (!name)
583 			continue;
584 
585 		/* The first white space is the end of variable name */
586 		val = skip_chars(name);
587 		len = strlen(name);
588 		if (val) {
589 			*val++ = '\0';
590 			if ((val - name) < len)
591 				val = skip_blanks(val);
592 			else
593 				val = NULL;
594 		}
595 
596 #ifdef DEBUG
597 		fprintf(stderr, "Setting %s : %s\n",
598 			name, val ? val : " removed");
599 #endif
600 
601 		if (env_flags_validate_type(name, val) < 0) {
602 			ret = -1;
603 			break;
604 		}
605 
606 		/*
607 		 * If there is an error setting a variable,
608 		 * try to save the environment and returns an error
609 		 */
610 		if (fw_env_write(name, val)) {
611 			fprintf(stderr,
612 			"fw_env_write returns with error : %s\n",
613 				strerror(errno));
614 			ret = -1;
615 			break;
616 		}
617 
618 	}
619 
620 	/* Close file if not stdin */
621 	if (strcmp(fname, "-") != 0)
622 		fclose(fp);
623 
624 	ret |= fw_env_close();
625 
626 	return ret;
627 
628 }
629 
630 /*
631  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
632  * 0	- block is good
633  * > 0	- block is bad
634  * < 0	- failed to test
635  */
636 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
637 {
638 	if (mtd_type == MTD_NANDFLASH) {
639 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
640 
641 		if (badblock < 0) {
642 			perror ("Cannot read bad block mark");
643 			return badblock;
644 		}
645 
646 		if (badblock) {
647 #ifdef DEBUG
648 			fprintf (stderr, "Bad block at 0x%llx, "
649 				 "skipping\n", *blockstart);
650 #endif
651 			return badblock;
652 		}
653 	}
654 
655 	return 0;
656 }
657 
658 /*
659  * Read data from flash at an offset into a provided buffer. On NAND it skips
660  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
661  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
662  */
663 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
664 			   off_t offset, uint8_t mtd_type)
665 {
666 	size_t blocklen;	/* erase / write length - one block on NAND,
667 				   0 on NOR */
668 	size_t processed = 0;	/* progress counter */
669 	size_t readlen = count;	/* current read length */
670 	off_t top_of_range;	/* end of the last block we may use */
671 	off_t block_seek;	/* offset inside the current block to the start
672 				   of the data */
673 	loff_t blockstart;	/* running start of the current block -
674 				   MEMGETBADBLOCK needs 64 bits */
675 	int rc;
676 
677 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
678 
679 	/* Offset inside a block */
680 	block_seek = offset - blockstart;
681 
682 	if (mtd_type == MTD_NANDFLASH) {
683 		/*
684 		 * NAND: calculate which blocks we are reading. We have
685 		 * to read one block at a time to skip bad blocks.
686 		 */
687 		blocklen = DEVESIZE (dev);
688 
689 		/*
690 		 * To calculate the top of the range, we have to use the
691 		 * global DEVOFFSET (dev), which can be different from offset
692 		 */
693 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
694 				ENVSECTORS (dev)) * blocklen;
695 
696 		/* Limit to one block for the first read */
697 		if (readlen > blocklen - block_seek)
698 			readlen = blocklen - block_seek;
699 	} else {
700 		blocklen = 0;
701 		top_of_range = offset + count;
702 	}
703 
704 	/* This only runs once on NOR flash */
705 	while (processed < count) {
706 		rc = flash_bad_block (fd, mtd_type, &blockstart);
707 		if (rc < 0)		/* block test failed */
708 			return -1;
709 
710 		if (blockstart + block_seek + readlen > top_of_range) {
711 			/* End of range is reached */
712 			fprintf (stderr,
713 				 "Too few good blocks within range\n");
714 			return -1;
715 		}
716 
717 		if (rc) {		/* block is bad */
718 			blockstart += blocklen;
719 			continue;
720 		}
721 
722 		/*
723 		 * If a block is bad, we retry in the next block at the same
724 		 * offset - see common/env_nand.c::writeenv()
725 		 */
726 		lseek (fd, blockstart + block_seek, SEEK_SET);
727 
728 		rc = read (fd, buf + processed, readlen);
729 		if (rc != readlen) {
730 			fprintf (stderr, "Read error on %s: %s\n",
731 				 DEVNAME (dev), strerror (errno));
732 			return -1;
733 		}
734 #ifdef DEBUG
735 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
736 			 rc, blockstart + block_seek, DEVNAME(dev));
737 #endif
738 		processed += readlen;
739 		readlen = min (blocklen, count - processed);
740 		block_seek = 0;
741 		blockstart += blocklen;
742 	}
743 
744 	return processed;
745 }
746 
747 /*
748  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
749  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
750  * erase and write the whole data at once.
751  */
752 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
753 			    off_t offset, uint8_t mtd_type)
754 {
755 	void *data;
756 	struct erase_info_user erase;
757 	size_t blocklen;	/* length of NAND block / NOR erase sector */
758 	size_t erase_len;	/* whole area that can be erased - may include
759 				   bad blocks */
760 	size_t erasesize;	/* erase / write length - one block on NAND,
761 				   whole area on NOR */
762 	size_t processed = 0;	/* progress counter */
763 	size_t write_total;	/* total size to actually write - excluding
764 				   bad blocks */
765 	off_t erase_offset;	/* offset to the first erase block (aligned)
766 				   below offset */
767 	off_t block_seek;	/* offset inside the erase block to the start
768 				   of the data */
769 	off_t top_of_range;	/* end of the last block we may use */
770 	loff_t blockstart;	/* running start of the current block -
771 				   MEMGETBADBLOCK needs 64 bits */
772 	int rc;
773 
774 	/*
775 	 * For mtd devices only offset and size of the environment do matter
776 	 */
777 	if (mtd_type == MTD_ABSENT) {
778 		blocklen = count;
779 		top_of_range = offset + count;
780 		erase_len = blocklen;
781 		blockstart = offset;
782 		block_seek = 0;
783 		write_total = blocklen;
784 	} else {
785 		blocklen = DEVESIZE(dev);
786 
787 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
788 					ENVSECTORS(dev)) * blocklen;
789 
790 		erase_offset = (offset / blocklen) * blocklen;
791 
792 		/* Maximum area we may use */
793 		erase_len = top_of_range - erase_offset;
794 
795 		blockstart = erase_offset;
796 		/* Offset inside a block */
797 		block_seek = offset - erase_offset;
798 
799 		/*
800 		 * Data size we actually write: from the start of the block
801 		 * to the start of the data, then count bytes of data, and
802 		 * to the end of the block
803 		 */
804 		write_total = ((block_seek + count + blocklen - 1) /
805 							blocklen) * blocklen;
806 	}
807 
808 	/*
809 	 * Support data anywhere within erase sectors: read out the complete
810 	 * area to be erased, replace the environment image, write the whole
811 	 * block back again.
812 	 */
813 	if (write_total > count) {
814 		data = malloc (erase_len);
815 		if (!data) {
816 			fprintf (stderr,
817 				 "Cannot malloc %zu bytes: %s\n",
818 				 erase_len, strerror (errno));
819 			return -1;
820 		}
821 
822 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
823 				     mtd_type);
824 		if (write_total != rc)
825 			return -1;
826 
827 #ifdef DEBUG
828 		fprintf(stderr, "Preserving data ");
829 		if (block_seek != 0)
830 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
831 		if (block_seek + count != write_total) {
832 			if (block_seek != 0)
833 				fprintf(stderr, " and ");
834 			fprintf(stderr, "0x%lx - 0x%x",
835 				block_seek + count, write_total - 1);
836 		}
837 		fprintf(stderr, "\n");
838 #endif
839 		/* Overwrite the old environment */
840 		memcpy (data + block_seek, buf, count);
841 	} else {
842 		/*
843 		 * We get here, iff offset is block-aligned and count is a
844 		 * multiple of blocklen - see write_total calculation above
845 		 */
846 		data = buf;
847 	}
848 
849 	if (mtd_type == MTD_NANDFLASH) {
850 		/*
851 		 * NAND: calculate which blocks we are writing. We have
852 		 * to write one block at a time to skip bad blocks.
853 		 */
854 		erasesize = blocklen;
855 	} else {
856 		erasesize = erase_len;
857 	}
858 
859 	erase.length = erasesize;
860 
861 	/* This only runs once on NOR flash and SPI-dataflash */
862 	while (processed < write_total) {
863 		rc = flash_bad_block (fd, mtd_type, &blockstart);
864 		if (rc < 0)		/* block test failed */
865 			return rc;
866 
867 		if (blockstart + erasesize > top_of_range) {
868 			fprintf (stderr, "End of range reached, aborting\n");
869 			return -1;
870 		}
871 
872 		if (rc) {		/* block is bad */
873 			blockstart += blocklen;
874 			continue;
875 		}
876 
877 		if (mtd_type != MTD_ABSENT) {
878 			erase.start = blockstart;
879 			ioctl(fd, MEMUNLOCK, &erase);
880 			/* These do not need an explicit erase cycle */
881 			if (mtd_type != MTD_DATAFLASH)
882 				if (ioctl(fd, MEMERASE, &erase) != 0) {
883 					fprintf(stderr,
884 						"MTD erase error on %s: %s\n",
885 						DEVNAME(dev), strerror(errno));
886 					return -1;
887 				}
888 		}
889 
890 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
891 			fprintf (stderr,
892 				 "Seek error on %s: %s\n",
893 				 DEVNAME (dev), strerror (errno));
894 			return -1;
895 		}
896 
897 #ifdef DEBUG
898 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
899 			blockstart);
900 #endif
901 		if (write (fd, data + processed, erasesize) != erasesize) {
902 			fprintf (stderr, "Write error on %s: %s\n",
903 				 DEVNAME (dev), strerror (errno));
904 			return -1;
905 		}
906 
907 		if (mtd_type != MTD_ABSENT)
908 			ioctl(fd, MEMLOCK, &erase);
909 
910 		processed  += erasesize;
911 		block_seek = 0;
912 		blockstart += erasesize;
913 	}
914 
915 	if (write_total > count)
916 		free (data);
917 
918 	return processed;
919 }
920 
921 /*
922  * Set obsolete flag at offset - NOR flash only
923  */
924 static int flash_flag_obsolete (int dev, int fd, off_t offset)
925 {
926 	int rc;
927 	struct erase_info_user erase;
928 
929 	erase.start  = DEVOFFSET (dev);
930 	erase.length = DEVESIZE (dev);
931 	/* This relies on the fact, that obsolete_flag == 0 */
932 	rc = lseek (fd, offset, SEEK_SET);
933 	if (rc < 0) {
934 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
935 			 DEVNAME (dev));
936 		return rc;
937 	}
938 	ioctl (fd, MEMUNLOCK, &erase);
939 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
940 	ioctl (fd, MEMLOCK, &erase);
941 	if (rc < 0)
942 		perror ("Could not set obsolete flag");
943 
944 	return rc;
945 }
946 
947 /* Encrypt or decrypt the environment before writing or reading it. */
948 static int env_aes_cbc_crypt(char *payload, const int enc)
949 {
950 	uint8_t *data = (uint8_t *)payload;
951 	const int len = getenvsize();
952 	uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
953 	uint32_t aes_blocks;
954 
955 	/* First we expand the key. */
956 	aes_expand_key(common_args.aes_key, key_exp);
957 
958 	/* Calculate the number of AES blocks to encrypt. */
959 	aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
960 
961 	if (enc)
962 		aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
963 	else
964 		aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
965 
966 	return 0;
967 }
968 
969 static int flash_write (int fd_current, int fd_target, int dev_target)
970 {
971 	int rc;
972 
973 	switch (environment.flag_scheme) {
974 	case FLAG_NONE:
975 		break;
976 	case FLAG_INCREMENTAL:
977 		(*environment.flags)++;
978 		break;
979 	case FLAG_BOOLEAN:
980 		*environment.flags = active_flag;
981 		break;
982 	default:
983 		fprintf (stderr, "Unimplemented flash scheme %u \n",
984 			 environment.flag_scheme);
985 		return -1;
986 	}
987 
988 #ifdef DEBUG
989 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
990 		DEVOFFSET (dev_target), DEVNAME (dev_target));
991 #endif
992 
993 	rc = flash_write_buf(dev_target, fd_target, environment.image,
994 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
995 			      DEVTYPE(dev_target));
996 	if (rc < 0)
997 		return rc;
998 
999 	if (environment.flag_scheme == FLAG_BOOLEAN) {
1000 		/* Have to set obsolete flag */
1001 		off_t offset = DEVOFFSET (dev_current) +
1002 			offsetof (struct env_image_redundant, flags);
1003 #ifdef DEBUG
1004 		fprintf(stderr,
1005 			"Setting obsolete flag in environment at 0x%lx on %s\n",
1006 			DEVOFFSET (dev_current), DEVNAME (dev_current));
1007 #endif
1008 		flash_flag_obsolete (dev_current, fd_current, offset);
1009 	}
1010 
1011 	return 0;
1012 }
1013 
1014 static int flash_read (int fd)
1015 {
1016 	struct mtd_info_user mtdinfo;
1017 	struct stat st;
1018 	int rc;
1019 
1020 	rc = fstat(fd, &st);
1021 	if (rc < 0) {
1022 		fprintf(stderr, "Cannot stat the file %s\n",
1023 			DEVNAME(dev_current));
1024 		return -1;
1025 	}
1026 
1027 	if (S_ISCHR(st.st_mode)) {
1028 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1029 		if (rc < 0) {
1030 			fprintf(stderr, "Cannot get MTD information for %s\n",
1031 				DEVNAME(dev_current));
1032 			return -1;
1033 		}
1034 		if (mtdinfo.type != MTD_NORFLASH &&
1035 		    mtdinfo.type != MTD_NANDFLASH &&
1036 		    mtdinfo.type != MTD_DATAFLASH &&
1037 		    mtdinfo.type != MTD_UBIVOLUME) {
1038 			fprintf (stderr, "Unsupported flash type %u on %s\n",
1039 				 mtdinfo.type, DEVNAME(dev_current));
1040 			return -1;
1041 		}
1042 	} else {
1043 		memset(&mtdinfo, 0, sizeof(mtdinfo));
1044 		mtdinfo.type = MTD_ABSENT;
1045 	}
1046 
1047 	DEVTYPE(dev_current) = mtdinfo.type;
1048 
1049 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1050 			     DEVOFFSET (dev_current), mtdinfo.type);
1051 	if (rc != CUR_ENVSIZE)
1052 		return -1;
1053 
1054 	return 0;
1055 }
1056 
1057 static int flash_io (int mode)
1058 {
1059 	int fd_current, fd_target, rc, dev_target;
1060 
1061 	/* dev_current: fd_current, erase_current */
1062 	fd_current = open (DEVNAME (dev_current), mode);
1063 	if (fd_current < 0) {
1064 		fprintf (stderr,
1065 			 "Can't open %s: %s\n",
1066 			 DEVNAME (dev_current), strerror (errno));
1067 		return -1;
1068 	}
1069 
1070 	if (mode == O_RDWR) {
1071 		if (HaveRedundEnv) {
1072 			/* switch to next partition for writing */
1073 			dev_target = !dev_current;
1074 			/* dev_target: fd_target, erase_target */
1075 			fd_target = open (DEVNAME (dev_target), mode);
1076 			if (fd_target < 0) {
1077 				fprintf (stderr,
1078 					 "Can't open %s: %s\n",
1079 					 DEVNAME (dev_target),
1080 					 strerror (errno));
1081 				rc = -1;
1082 				goto exit;
1083 			}
1084 		} else {
1085 			dev_target = dev_current;
1086 			fd_target = fd_current;
1087 		}
1088 
1089 		rc = flash_write (fd_current, fd_target, dev_target);
1090 
1091 		if (HaveRedundEnv) {
1092 			if (close (fd_target)) {
1093 				fprintf (stderr,
1094 					"I/O error on %s: %s\n",
1095 					DEVNAME (dev_target),
1096 					strerror (errno));
1097 				rc = -1;
1098 			}
1099 		}
1100 	} else {
1101 		rc = flash_read (fd_current);
1102 	}
1103 
1104 exit:
1105 	if (close (fd_current)) {
1106 		fprintf (stderr,
1107 			 "I/O error on %s: %s\n",
1108 			 DEVNAME (dev_current), strerror (errno));
1109 		return -1;
1110 	}
1111 
1112 	return rc;
1113 }
1114 
1115 /*
1116  * s1 is either a simple 'name', or a 'name=value' pair.
1117  * s2 is a 'name=value' pair.
1118  * If the names match, return the value of s2, else NULL.
1119  */
1120 
1121 static char *envmatch (char * s1, char * s2)
1122 {
1123 	if (s1 == NULL || s2 == NULL)
1124 		return NULL;
1125 
1126 	while (*s1 == *s2++)
1127 		if (*s1++ == '=')
1128 			return s2;
1129 	if (*s1 == '\0' && *(s2 - 1) == '=')
1130 		return s2;
1131 	return NULL;
1132 }
1133 
1134 /*
1135  * Prevent confusion if running from erased flash memory
1136  */
1137 int fw_env_open(void)
1138 {
1139 	int crc0, crc0_ok;
1140 	unsigned char flag0;
1141 	void *addr0;
1142 
1143 	int crc1, crc1_ok;
1144 	unsigned char flag1;
1145 	void *addr1;
1146 
1147 	int ret;
1148 
1149 	struct env_image_single *single;
1150 	struct env_image_redundant *redundant;
1151 
1152 	if (parse_config ())		/* should fill envdevices */
1153 		return -1;
1154 
1155 	addr0 = calloc(1, CUR_ENVSIZE);
1156 	if (addr0 == NULL) {
1157 		fprintf(stderr,
1158 			"Not enough memory for environment (%ld bytes)\n",
1159 			CUR_ENVSIZE);
1160 		return -1;
1161 	}
1162 
1163 	/* read environment from FLASH to local buffer */
1164 	environment.image = addr0;
1165 
1166 	if (HaveRedundEnv) {
1167 		redundant = addr0;
1168 		environment.crc		= &redundant->crc;
1169 		environment.flags	= &redundant->flags;
1170 		environment.data	= redundant->data;
1171 	} else {
1172 		single = addr0;
1173 		environment.crc		= &single->crc;
1174 		environment.flags	= NULL;
1175 		environment.data	= single->data;
1176 	}
1177 
1178 	dev_current = 0;
1179 	if (flash_io (O_RDONLY))
1180 		return -1;
1181 
1182 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1183 
1184 	if (common_args.aes_flag) {
1185 		ret = env_aes_cbc_crypt(environment.data, 0);
1186 		if (ret)
1187 			return ret;
1188 	}
1189 
1190 	crc0_ok = (crc0 == *environment.crc);
1191 	if (!HaveRedundEnv) {
1192 		if (!crc0_ok) {
1193 			fprintf (stderr,
1194 				"Warning: Bad CRC, using default environment\n");
1195 			memcpy(environment.data, default_environment, sizeof default_environment);
1196 		}
1197 	} else {
1198 		flag0 = *environment.flags;
1199 
1200 		dev_current = 1;
1201 		addr1 = calloc(1, CUR_ENVSIZE);
1202 		if (addr1 == NULL) {
1203 			fprintf(stderr,
1204 				"Not enough memory for environment (%ld bytes)\n",
1205 				CUR_ENVSIZE);
1206 			return -1;
1207 		}
1208 		redundant = addr1;
1209 
1210 		/*
1211 		 * have to set environment.image for flash_read(), careful -
1212 		 * other pointers in environment still point inside addr0
1213 		 */
1214 		environment.image = addr1;
1215 		if (flash_io (O_RDONLY))
1216 			return -1;
1217 
1218 		/* Check flag scheme compatibility */
1219 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1220 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1221 			environment.flag_scheme = FLAG_BOOLEAN;
1222 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1223 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1224 			environment.flag_scheme = FLAG_INCREMENTAL;
1225 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1226 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1227 			environment.flag_scheme = FLAG_BOOLEAN;
1228 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1229 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1230 			environment.flag_scheme = FLAG_INCREMENTAL;
1231 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1232 			   DEVTYPE(!dev_current) == MTD_ABSENT) {
1233 			environment.flag_scheme = FLAG_INCREMENTAL;
1234 		} else {
1235 			fprintf (stderr, "Incompatible flash types!\n");
1236 			return -1;
1237 		}
1238 
1239 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1240 
1241 		if (common_args.aes_flag) {
1242 			ret = env_aes_cbc_crypt(redundant->data, 0);
1243 			if (ret)
1244 				return ret;
1245 		}
1246 
1247 		crc1_ok = (crc1 == redundant->crc);
1248 		flag1 = redundant->flags;
1249 
1250 		if (crc0_ok && !crc1_ok) {
1251 			dev_current = 0;
1252 		} else if (!crc0_ok && crc1_ok) {
1253 			dev_current = 1;
1254 		} else if (!crc0_ok && !crc1_ok) {
1255 			fprintf (stderr,
1256 				"Warning: Bad CRC, using default environment\n");
1257 			memcpy (environment.data, default_environment,
1258 				sizeof default_environment);
1259 			dev_current = 0;
1260 		} else {
1261 			switch (environment.flag_scheme) {
1262 			case FLAG_BOOLEAN:
1263 				if (flag0 == active_flag &&
1264 				    flag1 == obsolete_flag) {
1265 					dev_current = 0;
1266 				} else if (flag0 == obsolete_flag &&
1267 					   flag1 == active_flag) {
1268 					dev_current = 1;
1269 				} else if (flag0 == flag1) {
1270 					dev_current = 0;
1271 				} else if (flag0 == 0xFF) {
1272 					dev_current = 0;
1273 				} else if (flag1 == 0xFF) {
1274 					dev_current = 1;
1275 				} else {
1276 					dev_current = 0;
1277 				}
1278 				break;
1279 			case FLAG_INCREMENTAL:
1280 				if (flag0 == 255 && flag1 == 0)
1281 					dev_current = 1;
1282 				else if ((flag1 == 255 && flag0 == 0) ||
1283 					 flag0 >= flag1)
1284 					dev_current = 0;
1285 				else /* flag1 > flag0 */
1286 					dev_current = 1;
1287 				break;
1288 			default:
1289 				fprintf (stderr, "Unknown flag scheme %u \n",
1290 					 environment.flag_scheme);
1291 				return -1;
1292 			}
1293 		}
1294 
1295 		/*
1296 		 * If we are reading, we don't need the flag and the CRC any
1297 		 * more, if we are writing, we will re-calculate CRC and update
1298 		 * flags before writing out
1299 		 */
1300 		if (dev_current) {
1301 			environment.image	= addr1;
1302 			environment.crc		= &redundant->crc;
1303 			environment.flags	= &redundant->flags;
1304 			environment.data	= redundant->data;
1305 			free (addr0);
1306 		} else {
1307 			environment.image	= addr0;
1308 			/* Other pointers are already set */
1309 			free (addr1);
1310 		}
1311 #ifdef DEBUG
1312 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1313 #endif
1314 	}
1315 	return 0;
1316 }
1317 
1318 
1319 static int parse_config ()
1320 {
1321 	struct stat st;
1322 
1323 #if defined(CONFIG_FILE)
1324 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1325 	if (get_config(common_args.config_file)) {
1326 		fprintf(stderr, "Cannot parse config file '%s': %m\n",
1327 			common_args.config_file);
1328 		return -1;
1329 	}
1330 #else
1331 	DEVNAME (0) = DEVICE1_NAME;
1332 	DEVOFFSET (0) = DEVICE1_OFFSET;
1333 	ENVSIZE (0) = ENV1_SIZE;
1334 	/* Default values are: erase-size=env-size */
1335 	DEVESIZE (0) = ENVSIZE (0);
1336 	/* #sectors=env-size/erase-size (rounded up) */
1337 	ENVSECTORS (0) = (ENVSIZE(0) + DEVESIZE(0) - 1) / DEVESIZE(0);
1338 #ifdef DEVICE1_ESIZE
1339 	DEVESIZE (0) = DEVICE1_ESIZE;
1340 #endif
1341 #ifdef DEVICE1_ENVSECTORS
1342 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1343 #endif
1344 
1345 #ifdef HAVE_REDUND
1346 	DEVNAME (1) = DEVICE2_NAME;
1347 	DEVOFFSET (1) = DEVICE2_OFFSET;
1348 	ENVSIZE (1) = ENV2_SIZE;
1349 	/* Default values are: erase-size=env-size */
1350 	DEVESIZE (1) = ENVSIZE (1);
1351 	/* #sectors=env-size/erase-size (rounded up) */
1352 	ENVSECTORS (1) = (ENVSIZE(1) + DEVESIZE(1) - 1) / DEVESIZE(1);
1353 #ifdef DEVICE2_ESIZE
1354 	DEVESIZE (1) = DEVICE2_ESIZE;
1355 #endif
1356 #ifdef DEVICE2_ENVSECTORS
1357 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1358 #endif
1359 	HaveRedundEnv = 1;
1360 #endif
1361 #endif
1362 	if (stat (DEVNAME (0), &st)) {
1363 		fprintf (stderr,
1364 			"Cannot access MTD device %s: %s\n",
1365 			DEVNAME (0), strerror (errno));
1366 		return -1;
1367 	}
1368 
1369 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1370 		fprintf (stderr,
1371 			"Cannot access MTD device %s: %s\n",
1372 			DEVNAME (1), strerror (errno));
1373 		return -1;
1374 	}
1375 	return 0;
1376 }
1377 
1378 #if defined(CONFIG_FILE)
1379 static int get_config (char *fname)
1380 {
1381 	FILE *fp;
1382 	int i = 0;
1383 	int rc;
1384 	char dump[128];
1385 	char *devname;
1386 
1387 	fp = fopen (fname, "r");
1388 	if (fp == NULL)
1389 		return -1;
1390 
1391 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1392 		/* Skip incomplete conversions and comment strings */
1393 		if (dump[0] == '#')
1394 			continue;
1395 
1396 		rc = sscanf (dump, "%ms %lx %lx %lx %lx",
1397 			     &devname,
1398 			     &DEVOFFSET (i),
1399 			     &ENVSIZE (i),
1400 			     &DEVESIZE (i),
1401 			     &ENVSECTORS (i));
1402 
1403 		if (rc < 3)
1404 			continue;
1405 
1406 		DEVNAME(i) = devname;
1407 
1408 		if (rc < 4)
1409 			/* Assume the erase size is the same as the env-size */
1410 			DEVESIZE(i) = ENVSIZE(i);
1411 
1412 		if (rc < 5)
1413 			/* Assume enough env sectors to cover the environment */
1414 			ENVSECTORS (i) = (ENVSIZE(i) + DEVESIZE(i) - 1) / DEVESIZE(i);
1415 
1416 		i++;
1417 	}
1418 	fclose (fp);
1419 
1420 	HaveRedundEnv = i - 1;
1421 	if (!i) {			/* No valid entries found */
1422 		errno = EINVAL;
1423 		return -1;
1424 	} else
1425 		return 0;
1426 }
1427 #endif
1428