xref: /rk3399_rockchip-uboot/tools/env/fw_env.c (revision 9583efcc74f9e781773706126315d4e9f8c9d43e)
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 *fw_string_blank(char *s, int noblank)
137 {
138 	int i;
139 	int len = strlen(s);
140 
141 	for (i = 0; i < len; i++, s++) {
142 		if ((noblank && !isblank(*s)) ||
143 		    (!noblank && isblank(*s)))
144 			return s;
145 	}
146 	return NULL;
147 }
148 
149 /*
150  * Search the environment for a variable.
151  * Return the value, if found, or NULL, if not found.
152  */
153 char *fw_getenv (char *name)
154 {
155 	char *env, *nxt;
156 
157 	for (env = environment.data; *env; env = nxt + 1) {
158 		char *val;
159 
160 		for (nxt = env; *nxt; ++nxt) {
161 			if (nxt >= &environment.data[ENV_SIZE]) {
162 				fprintf (stderr, "## Error: "
163 					"environment not terminated\n");
164 				return NULL;
165 			}
166 		}
167 		val = envmatch (name, env);
168 		if (!val)
169 			continue;
170 		return val;
171 	}
172 	return NULL;
173 }
174 
175 /*
176  * Search the default environment for a variable.
177  * Return the value, if found, or NULL, if not found.
178  */
179 char *fw_getdefenv(char *name)
180 {
181 	char *env, *nxt;
182 
183 	for (env = default_environment; *env; env = nxt + 1) {
184 		char *val;
185 
186 		for (nxt = env; *nxt; ++nxt) {
187 			if (nxt >= &default_environment[ENV_SIZE]) {
188 				fprintf(stderr, "## Error: "
189 					"default environment not terminated\n");
190 				return NULL;
191 			}
192 		}
193 		val = envmatch(name, env);
194 		if (!val)
195 			continue;
196 		return val;
197 	}
198 	return NULL;
199 }
200 
201 int parse_aes_key(char *key, uint8_t *bin_key)
202 {
203 	char tmp[5] = { '0', 'x', 0, 0, 0 };
204 	unsigned long ul;
205 	int i;
206 
207 	if (strnlen(key, 64) != 32) {
208 		fprintf(stderr,
209 			"## Error: '-a' option requires 16-byte AES key\n");
210 		return -1;
211 	}
212 
213 	for (i = 0; i < 16; i++) {
214 		tmp[2] = key[0];
215 		tmp[3] = key[1];
216 		errno = 0;
217 		ul = strtoul(tmp, NULL, 16);
218 		if (errno) {
219 			fprintf(stderr,
220 				"## Error: '-a' option requires valid AES key\n");
221 			return -1;
222 		}
223 		bin_key[i] = ul & 0xff;
224 		key += 2;
225 	}
226 	return 0;
227 }
228 
229 /*
230  * Print the current definition of one, or more, or all
231  * environment variables
232  */
233 int fw_printenv (int argc, char *argv[])
234 {
235 	char *env, *nxt;
236 	int i, rc = 0;
237 
238 	if (fw_env_open())
239 		return -1;
240 
241 	if (argc == 0) {		/* Print all env variables  */
242 		for (env = environment.data; *env; env = nxt + 1) {
243 			for (nxt = env; *nxt; ++nxt) {
244 				if (nxt >= &environment.data[ENV_SIZE]) {
245 					fprintf (stderr, "## Error: "
246 						"environment not terminated\n");
247 					return -1;
248 				}
249 			}
250 
251 			printf ("%s\n", env);
252 		}
253 		return 0;
254 	}
255 
256 	if (printenv_args.name_suppress && argc != 1) {
257 		fprintf(stderr,
258 			"## Error: `-n' option requires exactly one argument\n");
259 		return -1;
260 	}
261 
262 	for (i = 0; i < argc; ++i) {	/* print single env variables   */
263 		char *name = argv[i];
264 		char *val = NULL;
265 
266 		for (env = environment.data; *env; env = nxt + 1) {
267 
268 			for (nxt = env; *nxt; ++nxt) {
269 				if (nxt >= &environment.data[ENV_SIZE]) {
270 					fprintf (stderr, "## Error: "
271 						"environment not terminated\n");
272 					return -1;
273 				}
274 			}
275 			val = envmatch (name, env);
276 			if (val) {
277 				if (!printenv_args.name_suppress) {
278 					fputs (name, stdout);
279 					putc ('=', stdout);
280 				}
281 				puts (val);
282 				break;
283 			}
284 		}
285 		if (!val) {
286 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
287 			rc = -1;
288 		}
289 	}
290 
291 	return rc;
292 }
293 
294 int fw_env_close(void)
295 {
296 	int ret;
297 	if (common_args.aes_flag) {
298 		ret = env_aes_cbc_crypt(environment.data, 1);
299 		if (ret) {
300 			fprintf(stderr,
301 				"Error: can't encrypt env for flash\n");
302 			return ret;
303 		}
304 	}
305 
306 	/*
307 	 * Update CRC
308 	 */
309 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
310 
311 	/* write environment back to flash */
312 	if (flash_io(O_RDWR)) {
313 		fprintf(stderr,
314 			"Error: can't write fw_env to flash\n");
315 			return -1;
316 	}
317 
318 	return 0;
319 }
320 
321 
322 /*
323  * Set/Clear a single variable in the environment.
324  * This is called in sequence to update the environment
325  * in RAM without updating the copy in flash after each set
326  */
327 int fw_env_write(char *name, char *value)
328 {
329 	int len;
330 	char *env, *nxt;
331 	char *oldval = NULL;
332 	int deleting, creating, overwriting;
333 
334 	/*
335 	 * search if variable with this name already exists
336 	 */
337 	for (nxt = env = environment.data; *env; env = nxt + 1) {
338 		for (nxt = env; *nxt; ++nxt) {
339 			if (nxt >= &environment.data[ENV_SIZE]) {
340 				fprintf(stderr, "## Error: "
341 					"environment not terminated\n");
342 				errno = EINVAL;
343 				return -1;
344 			}
345 		}
346 		if ((oldval = envmatch (name, env)) != NULL)
347 			break;
348 	}
349 
350 	deleting = (oldval && !(value && strlen(value)));
351 	creating = (!oldval && (value && strlen(value)));
352 	overwriting = (oldval && (value && strlen(value)));
353 
354 	/* check for permission */
355 	if (deleting) {
356 		if (env_flags_validate_varaccess(name,
357 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
358 			printf("Can't delete \"%s\"\n", name);
359 			errno = EROFS;
360 			return -1;
361 		}
362 	} else if (overwriting) {
363 		if (env_flags_validate_varaccess(name,
364 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
365 			printf("Can't overwrite \"%s\"\n", name);
366 			errno = EROFS;
367 			return -1;
368 		} else if (env_flags_validate_varaccess(name,
369 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
370 			const char *defval = fw_getdefenv(name);
371 
372 			if (defval == NULL)
373 				defval = "";
374 			if (strcmp(oldval, defval)
375 			    != 0) {
376 				printf("Can't overwrite \"%s\"\n", name);
377 				errno = EROFS;
378 				return -1;
379 			}
380 		}
381 	} else if (creating) {
382 		if (env_flags_validate_varaccess(name,
383 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
384 			printf("Can't create \"%s\"\n", name);
385 			errno = EROFS;
386 			return -1;
387 		}
388 	} else
389 		/* Nothing to do */
390 		return 0;
391 
392 	if (deleting || overwriting) {
393 		if (*++nxt == '\0') {
394 			*env = '\0';
395 		} else {
396 			for (;;) {
397 				*env = *nxt++;
398 				if ((*env == '\0') && (*nxt == '\0'))
399 					break;
400 				++env;
401 			}
402 		}
403 		*++env = '\0';
404 	}
405 
406 	/* Delete only ? */
407 	if (!value || !strlen(value))
408 		return 0;
409 
410 	/*
411 	 * Append new definition at the end
412 	 */
413 	for (env = environment.data; *env || *(env + 1); ++env);
414 	if (env > environment.data)
415 		++env;
416 	/*
417 	 * Overflow when:
418 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
419 	 */
420 	len = strlen (name) + 2;
421 	/* add '=' for first arg, ' ' for all others */
422 	len += strlen(value) + 1;
423 
424 	if (len > (&environment.data[ENV_SIZE] - env)) {
425 		fprintf (stderr,
426 			"Error: environment overflow, \"%s\" deleted\n",
427 			name);
428 		return -1;
429 	}
430 
431 	while ((*env = *name++) != '\0')
432 		env++;
433 	*env = '=';
434 	while ((*++env = *value++) != '\0')
435 		;
436 
437 	/* end is marked with double '\0' */
438 	*++env = '\0';
439 
440 	return 0;
441 }
442 
443 /*
444  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
445  * 0	  - OK
446  * EINVAL - need at least 1 argument
447  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
448  *	    modified or deleted
449  *
450  */
451 int fw_setenv(int argc, char *argv[])
452 {
453 	int i;
454 	size_t len;
455 	char *name, **valv;
456 	char *value = NULL;
457 	int valc;
458 
459 	if (argc < 1) {
460 		fprintf(stderr, "## Error: variable name missing\n");
461 		errno = EINVAL;
462 		return -1;
463 	}
464 
465 	if (fw_env_open()) {
466 		fprintf(stderr, "Error: environment not initialized\n");
467 		return -1;
468 	}
469 
470 	name = argv[0];
471 	valv = argv + 1;
472 	valc = argc - 1;
473 
474 	if (env_flags_validate_env_set_params(name, valv, valc) < 0)
475 		return 1;
476 
477 	len = 0;
478 	for (i = 0; i < valc; ++i) {
479 		char *val = valv[i];
480 		size_t val_len = strlen(val);
481 
482 		if (value)
483 			value[len - 1] = ' ';
484 		value = realloc(value, len + val_len + 1);
485 		if (!value) {
486 			fprintf(stderr,
487 				"Cannot malloc %zu bytes: %s\n",
488 				len, strerror(errno));
489 			return -1;
490 		}
491 
492 		memcpy(value + len, val, val_len);
493 		len += val_len;
494 		value[len++] = '\0';
495 	}
496 
497 	fw_env_write(name, value);
498 
499 	free(value);
500 
501 	return fw_env_close();
502 }
503 
504 /*
505  * Parse  a file  and configure the u-boot variables.
506  * The script file has a very simple format, as follows:
507  *
508  * Each line has a couple with name, value:
509  * <white spaces>variable_name<white spaces>variable_value
510  *
511  * Both variable_name and variable_value are interpreted as strings.
512  * Any character after <white spaces> and before ending \r\n is interpreted
513  * as variable's value (no comment allowed on these lines !)
514  *
515  * Comments are allowed if the first character in the line is #
516  *
517  * Returns -1 and sets errno error codes:
518  * 0	  - OK
519  * -1     - Error
520  */
521 int fw_parse_script(char *fname)
522 {
523 	FILE *fp;
524 	char dump[1024];	/* Maximum line length in the file */
525 	char *name;
526 	char *val;
527 	int lineno = 0;
528 	int len;
529 	int ret = 0;
530 
531 	if (fw_env_open()) {
532 		fprintf(stderr, "Error: environment not initialized\n");
533 		return -1;
534 	}
535 
536 	if (strcmp(fname, "-") == 0)
537 		fp = stdin;
538 	else {
539 		fp = fopen(fname, "r");
540 		if (fp == NULL) {
541 			fprintf(stderr, "I cannot open %s for reading\n",
542 				 fname);
543 			return -1;
544 		}
545 	}
546 
547 	while (fgets(dump, sizeof(dump), fp)) {
548 		lineno++;
549 		len = strlen(dump);
550 
551 		/*
552 		 * Read a whole line from the file. If the line is too long
553 		 * or is not terminated, reports an error and exit.
554 		 */
555 		if (dump[len - 1] != '\n') {
556 			fprintf(stderr,
557 			"Line %d not corrected terminated or too long\n",
558 				lineno);
559 			ret = -1;
560 			break;
561 		}
562 
563 		/* Drop ending line feed / carriage return */
564 		while (len > 0 && (dump[len - 1] == '\n' ||
565 				dump[len - 1] == '\r')) {
566 			dump[len - 1] = '\0';
567 			len--;
568 		}
569 
570 		/* Skip comment or empty lines */
571 		if ((len == 0) || dump[0] == '#')
572 			continue;
573 
574 		/*
575 		 * Search for variable's name,
576 		 * remove leading whitespaces
577 		 */
578 		name = fw_string_blank(dump, 1);
579 		if (!name)
580 			continue;
581 
582 		/* The first white space is the end of variable name */
583 		val = fw_string_blank(name, 0);
584 		len = strlen(name);
585 		if (val) {
586 			*val++ = '\0';
587 			if ((val - name) < len)
588 				val = fw_string_blank(val, 1);
589 			else
590 				val = NULL;
591 		}
592 
593 #ifdef DEBUG
594 		fprintf(stderr, "Setting %s : %s\n",
595 			name, val ? val : " removed");
596 #endif
597 
598 		if (env_flags_validate_type(name, val) < 0) {
599 			ret = -1;
600 			break;
601 		}
602 
603 		/*
604 		 * If there is an error setting a variable,
605 		 * try to save the environment and returns an error
606 		 */
607 		if (fw_env_write(name, val)) {
608 			fprintf(stderr,
609 			"fw_env_write returns with error : %s\n",
610 				strerror(errno));
611 			ret = -1;
612 			break;
613 		}
614 
615 	}
616 
617 	/* Close file if not stdin */
618 	if (strcmp(fname, "-") != 0)
619 		fclose(fp);
620 
621 	ret |= fw_env_close();
622 
623 	return ret;
624 
625 }
626 
627 /*
628  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
629  * 0	- block is good
630  * > 0	- block is bad
631  * < 0	- failed to test
632  */
633 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
634 {
635 	if (mtd_type == MTD_NANDFLASH) {
636 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
637 
638 		if (badblock < 0) {
639 			perror ("Cannot read bad block mark");
640 			return badblock;
641 		}
642 
643 		if (badblock) {
644 #ifdef DEBUG
645 			fprintf (stderr, "Bad block at 0x%llx, "
646 				 "skipping\n", *blockstart);
647 #endif
648 			return badblock;
649 		}
650 	}
651 
652 	return 0;
653 }
654 
655 /*
656  * Read data from flash at an offset into a provided buffer. On NAND it skips
657  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
658  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
659  */
660 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
661 			   off_t offset, uint8_t mtd_type)
662 {
663 	size_t blocklen;	/* erase / write length - one block on NAND,
664 				   0 on NOR */
665 	size_t processed = 0;	/* progress counter */
666 	size_t readlen = count;	/* current read length */
667 	off_t top_of_range;	/* end of the last block we may use */
668 	off_t block_seek;	/* offset inside the current block to the start
669 				   of the data */
670 	loff_t blockstart;	/* running start of the current block -
671 				   MEMGETBADBLOCK needs 64 bits */
672 	int rc;
673 
674 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
675 
676 	/* Offset inside a block */
677 	block_seek = offset - blockstart;
678 
679 	if (mtd_type == MTD_NANDFLASH) {
680 		/*
681 		 * NAND: calculate which blocks we are reading. We have
682 		 * to read one block at a time to skip bad blocks.
683 		 */
684 		blocklen = DEVESIZE (dev);
685 
686 		/*
687 		 * To calculate the top of the range, we have to use the
688 		 * global DEVOFFSET (dev), which can be different from offset
689 		 */
690 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
691 				ENVSECTORS (dev)) * blocklen;
692 
693 		/* Limit to one block for the first read */
694 		if (readlen > blocklen - block_seek)
695 			readlen = blocklen - block_seek;
696 	} else {
697 		blocklen = 0;
698 		top_of_range = offset + count;
699 	}
700 
701 	/* This only runs once on NOR flash */
702 	while (processed < count) {
703 		rc = flash_bad_block (fd, mtd_type, &blockstart);
704 		if (rc < 0)		/* block test failed */
705 			return -1;
706 
707 		if (blockstart + block_seek + readlen > top_of_range) {
708 			/* End of range is reached */
709 			fprintf (stderr,
710 				 "Too few good blocks within range\n");
711 			return -1;
712 		}
713 
714 		if (rc) {		/* block is bad */
715 			blockstart += blocklen;
716 			continue;
717 		}
718 
719 		/*
720 		 * If a block is bad, we retry in the next block at the same
721 		 * offset - see common/env_nand.c::writeenv()
722 		 */
723 		lseek (fd, blockstart + block_seek, SEEK_SET);
724 
725 		rc = read (fd, buf + processed, readlen);
726 		if (rc != readlen) {
727 			fprintf (stderr, "Read error on %s: %s\n",
728 				 DEVNAME (dev), strerror (errno));
729 			return -1;
730 		}
731 #ifdef DEBUG
732 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
733 			 rc, blockstart + block_seek, DEVNAME(dev));
734 #endif
735 		processed += readlen;
736 		readlen = min (blocklen, count - processed);
737 		block_seek = 0;
738 		blockstart += blocklen;
739 	}
740 
741 	return processed;
742 }
743 
744 /*
745  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
746  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
747  * erase and write the whole data at once.
748  */
749 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
750 			    off_t offset, uint8_t mtd_type)
751 {
752 	void *data;
753 	struct erase_info_user erase;
754 	size_t blocklen;	/* length of NAND block / NOR erase sector */
755 	size_t erase_len;	/* whole area that can be erased - may include
756 				   bad blocks */
757 	size_t erasesize;	/* erase / write length - one block on NAND,
758 				   whole area on NOR */
759 	size_t processed = 0;	/* progress counter */
760 	size_t write_total;	/* total size to actually write - excluding
761 				   bad blocks */
762 	off_t erase_offset;	/* offset to the first erase block (aligned)
763 				   below offset */
764 	off_t block_seek;	/* offset inside the erase block to the start
765 				   of the data */
766 	off_t top_of_range;	/* end of the last block we may use */
767 	loff_t blockstart;	/* running start of the current block -
768 				   MEMGETBADBLOCK needs 64 bits */
769 	int rc;
770 
771 	/*
772 	 * For mtd devices only offset and size of the environment do matter
773 	 */
774 	if (mtd_type == MTD_ABSENT) {
775 		blocklen = count;
776 		top_of_range = offset + count;
777 		erase_len = blocklen;
778 		blockstart = offset;
779 		block_seek = 0;
780 		write_total = blocklen;
781 	} else {
782 		blocklen = DEVESIZE(dev);
783 
784 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
785 					ENVSECTORS(dev)) * blocklen;
786 
787 		erase_offset = (offset / blocklen) * blocklen;
788 
789 		/* Maximum area we may use */
790 		erase_len = top_of_range - erase_offset;
791 
792 		blockstart = erase_offset;
793 		/* Offset inside a block */
794 		block_seek = offset - erase_offset;
795 
796 		/*
797 		 * Data size we actually write: from the start of the block
798 		 * to the start of the data, then count bytes of data, and
799 		 * to the end of the block
800 		 */
801 		write_total = ((block_seek + count + blocklen - 1) /
802 							blocklen) * blocklen;
803 	}
804 
805 	/*
806 	 * Support data anywhere within erase sectors: read out the complete
807 	 * area to be erased, replace the environment image, write the whole
808 	 * block back again.
809 	 */
810 	if (write_total > count) {
811 		data = malloc (erase_len);
812 		if (!data) {
813 			fprintf (stderr,
814 				 "Cannot malloc %zu bytes: %s\n",
815 				 erase_len, strerror (errno));
816 			return -1;
817 		}
818 
819 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
820 				     mtd_type);
821 		if (write_total != rc)
822 			return -1;
823 
824 #ifdef DEBUG
825 		fprintf(stderr, "Preserving data ");
826 		if (block_seek != 0)
827 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
828 		if (block_seek + count != write_total) {
829 			if (block_seek != 0)
830 				fprintf(stderr, " and ");
831 			fprintf(stderr, "0x%lx - 0x%x",
832 				block_seek + count, write_total - 1);
833 		}
834 		fprintf(stderr, "\n");
835 #endif
836 		/* Overwrite the old environment */
837 		memcpy (data + block_seek, buf, count);
838 	} else {
839 		/*
840 		 * We get here, iff offset is block-aligned and count is a
841 		 * multiple of blocklen - see write_total calculation above
842 		 */
843 		data = buf;
844 	}
845 
846 	if (mtd_type == MTD_NANDFLASH) {
847 		/*
848 		 * NAND: calculate which blocks we are writing. We have
849 		 * to write one block at a time to skip bad blocks.
850 		 */
851 		erasesize = blocklen;
852 	} else {
853 		erasesize = erase_len;
854 	}
855 
856 	erase.length = erasesize;
857 
858 	/* This only runs once on NOR flash and SPI-dataflash */
859 	while (processed < write_total) {
860 		rc = flash_bad_block (fd, mtd_type, &blockstart);
861 		if (rc < 0)		/* block test failed */
862 			return rc;
863 
864 		if (blockstart + erasesize > top_of_range) {
865 			fprintf (stderr, "End of range reached, aborting\n");
866 			return -1;
867 		}
868 
869 		if (rc) {		/* block is bad */
870 			blockstart += blocklen;
871 			continue;
872 		}
873 
874 		if (mtd_type != MTD_ABSENT) {
875 			erase.start = blockstart;
876 			ioctl(fd, MEMUNLOCK, &erase);
877 			/* These do not need an explicit erase cycle */
878 			if (mtd_type != MTD_DATAFLASH)
879 				if (ioctl(fd, MEMERASE, &erase) != 0) {
880 					fprintf(stderr,
881 						"MTD erase error on %s: %s\n",
882 						DEVNAME(dev), strerror(errno));
883 					return -1;
884 				}
885 		}
886 
887 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
888 			fprintf (stderr,
889 				 "Seek error on %s: %s\n",
890 				 DEVNAME (dev), strerror (errno));
891 			return -1;
892 		}
893 
894 #ifdef DEBUG
895 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
896 			blockstart);
897 #endif
898 		if (write (fd, data + processed, erasesize) != erasesize) {
899 			fprintf (stderr, "Write error on %s: %s\n",
900 				 DEVNAME (dev), strerror (errno));
901 			return -1;
902 		}
903 
904 		if (mtd_type != MTD_ABSENT)
905 			ioctl(fd, MEMLOCK, &erase);
906 
907 		processed  += erasesize;
908 		block_seek = 0;
909 		blockstart += erasesize;
910 	}
911 
912 	if (write_total > count)
913 		free (data);
914 
915 	return processed;
916 }
917 
918 /*
919  * Set obsolete flag at offset - NOR flash only
920  */
921 static int flash_flag_obsolete (int dev, int fd, off_t offset)
922 {
923 	int rc;
924 	struct erase_info_user erase;
925 
926 	erase.start  = DEVOFFSET (dev);
927 	erase.length = DEVESIZE (dev);
928 	/* This relies on the fact, that obsolete_flag == 0 */
929 	rc = lseek (fd, offset, SEEK_SET);
930 	if (rc < 0) {
931 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
932 			 DEVNAME (dev));
933 		return rc;
934 	}
935 	ioctl (fd, MEMUNLOCK, &erase);
936 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
937 	ioctl (fd, MEMLOCK, &erase);
938 	if (rc < 0)
939 		perror ("Could not set obsolete flag");
940 
941 	return rc;
942 }
943 
944 /* Encrypt or decrypt the environment before writing or reading it. */
945 static int env_aes_cbc_crypt(char *payload, const int enc)
946 {
947 	uint8_t *data = (uint8_t *)payload;
948 	const int len = getenvsize();
949 	uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
950 	uint32_t aes_blocks;
951 
952 	/* First we expand the key. */
953 	aes_expand_key(common_args.aes_key, key_exp);
954 
955 	/* Calculate the number of AES blocks to encrypt. */
956 	aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
957 
958 	if (enc)
959 		aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
960 	else
961 		aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
962 
963 	return 0;
964 }
965 
966 static int flash_write (int fd_current, int fd_target, int dev_target)
967 {
968 	int rc;
969 
970 	switch (environment.flag_scheme) {
971 	case FLAG_NONE:
972 		break;
973 	case FLAG_INCREMENTAL:
974 		(*environment.flags)++;
975 		break;
976 	case FLAG_BOOLEAN:
977 		*environment.flags = active_flag;
978 		break;
979 	default:
980 		fprintf (stderr, "Unimplemented flash scheme %u \n",
981 			 environment.flag_scheme);
982 		return -1;
983 	}
984 
985 #ifdef DEBUG
986 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
987 		DEVOFFSET (dev_target), DEVNAME (dev_target));
988 #endif
989 
990 	rc = flash_write_buf(dev_target, fd_target, environment.image,
991 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
992 			      DEVTYPE(dev_target));
993 	if (rc < 0)
994 		return rc;
995 
996 	if (environment.flag_scheme == FLAG_BOOLEAN) {
997 		/* Have to set obsolete flag */
998 		off_t offset = DEVOFFSET (dev_current) +
999 			offsetof (struct env_image_redundant, flags);
1000 #ifdef DEBUG
1001 		fprintf(stderr,
1002 			"Setting obsolete flag in environment at 0x%lx on %s\n",
1003 			DEVOFFSET (dev_current), DEVNAME (dev_current));
1004 #endif
1005 		flash_flag_obsolete (dev_current, fd_current, offset);
1006 	}
1007 
1008 	return 0;
1009 }
1010 
1011 static int flash_read (int fd)
1012 {
1013 	struct mtd_info_user mtdinfo;
1014 	struct stat st;
1015 	int rc;
1016 
1017 	rc = fstat(fd, &st);
1018 	if (rc < 0) {
1019 		fprintf(stderr, "Cannot stat the file %s\n",
1020 			DEVNAME(dev_current));
1021 		return -1;
1022 	}
1023 
1024 	if (S_ISCHR(st.st_mode)) {
1025 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1026 		if (rc < 0) {
1027 			fprintf(stderr, "Cannot get MTD information for %s\n",
1028 				DEVNAME(dev_current));
1029 			return -1;
1030 		}
1031 		if (mtdinfo.type != MTD_NORFLASH &&
1032 		    mtdinfo.type != MTD_NANDFLASH &&
1033 		    mtdinfo.type != MTD_DATAFLASH &&
1034 		    mtdinfo.type != MTD_UBIVOLUME) {
1035 			fprintf (stderr, "Unsupported flash type %u on %s\n",
1036 				 mtdinfo.type, DEVNAME(dev_current));
1037 			return -1;
1038 		}
1039 	} else {
1040 		memset(&mtdinfo, 0, sizeof(mtdinfo));
1041 		mtdinfo.type = MTD_ABSENT;
1042 	}
1043 
1044 	DEVTYPE(dev_current) = mtdinfo.type;
1045 
1046 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1047 			     DEVOFFSET (dev_current), mtdinfo.type);
1048 	if (rc != CUR_ENVSIZE)
1049 		return -1;
1050 
1051 	return 0;
1052 }
1053 
1054 static int flash_io (int mode)
1055 {
1056 	int fd_current, fd_target, rc, dev_target;
1057 
1058 	/* dev_current: fd_current, erase_current */
1059 	fd_current = open (DEVNAME (dev_current), mode);
1060 	if (fd_current < 0) {
1061 		fprintf (stderr,
1062 			 "Can't open %s: %s\n",
1063 			 DEVNAME (dev_current), strerror (errno));
1064 		return -1;
1065 	}
1066 
1067 	if (mode == O_RDWR) {
1068 		if (HaveRedundEnv) {
1069 			/* switch to next partition for writing */
1070 			dev_target = !dev_current;
1071 			/* dev_target: fd_target, erase_target */
1072 			fd_target = open (DEVNAME (dev_target), mode);
1073 			if (fd_target < 0) {
1074 				fprintf (stderr,
1075 					 "Can't open %s: %s\n",
1076 					 DEVNAME (dev_target),
1077 					 strerror (errno));
1078 				rc = -1;
1079 				goto exit;
1080 			}
1081 		} else {
1082 			dev_target = dev_current;
1083 			fd_target = fd_current;
1084 		}
1085 
1086 		rc = flash_write (fd_current, fd_target, dev_target);
1087 
1088 		if (HaveRedundEnv) {
1089 			if (close (fd_target)) {
1090 				fprintf (stderr,
1091 					"I/O error on %s: %s\n",
1092 					DEVNAME (dev_target),
1093 					strerror (errno));
1094 				rc = -1;
1095 			}
1096 		}
1097 	} else {
1098 		rc = flash_read (fd_current);
1099 	}
1100 
1101 exit:
1102 	if (close (fd_current)) {
1103 		fprintf (stderr,
1104 			 "I/O error on %s: %s\n",
1105 			 DEVNAME (dev_current), strerror (errno));
1106 		return -1;
1107 	}
1108 
1109 	return rc;
1110 }
1111 
1112 /*
1113  * s1 is either a simple 'name', or a 'name=value' pair.
1114  * s2 is a 'name=value' pair.
1115  * If the names match, return the value of s2, else NULL.
1116  */
1117 
1118 static char *envmatch (char * s1, char * s2)
1119 {
1120 	if (s1 == NULL || s2 == NULL)
1121 		return NULL;
1122 
1123 	while (*s1 == *s2++)
1124 		if (*s1++ == '=')
1125 			return s2;
1126 	if (*s1 == '\0' && *(s2 - 1) == '=')
1127 		return s2;
1128 	return NULL;
1129 }
1130 
1131 /*
1132  * Prevent confusion if running from erased flash memory
1133  */
1134 int fw_env_open(void)
1135 {
1136 	int crc0, crc0_ok;
1137 	unsigned char flag0;
1138 	void *addr0;
1139 
1140 	int crc1, crc1_ok;
1141 	unsigned char flag1;
1142 	void *addr1;
1143 
1144 	int ret;
1145 
1146 	struct env_image_single *single;
1147 	struct env_image_redundant *redundant;
1148 
1149 	if (parse_config ())		/* should fill envdevices */
1150 		return -1;
1151 
1152 	addr0 = calloc(1, CUR_ENVSIZE);
1153 	if (addr0 == NULL) {
1154 		fprintf(stderr,
1155 			"Not enough memory for environment (%ld bytes)\n",
1156 			CUR_ENVSIZE);
1157 		return -1;
1158 	}
1159 
1160 	/* read environment from FLASH to local buffer */
1161 	environment.image = addr0;
1162 
1163 	if (HaveRedundEnv) {
1164 		redundant = addr0;
1165 		environment.crc		= &redundant->crc;
1166 		environment.flags	= &redundant->flags;
1167 		environment.data	= redundant->data;
1168 	} else {
1169 		single = addr0;
1170 		environment.crc		= &single->crc;
1171 		environment.flags	= NULL;
1172 		environment.data	= single->data;
1173 	}
1174 
1175 	dev_current = 0;
1176 	if (flash_io (O_RDONLY))
1177 		return -1;
1178 
1179 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1180 
1181 	if (common_args.aes_flag) {
1182 		ret = env_aes_cbc_crypt(environment.data, 0);
1183 		if (ret)
1184 			return ret;
1185 	}
1186 
1187 	crc0_ok = (crc0 == *environment.crc);
1188 	if (!HaveRedundEnv) {
1189 		if (!crc0_ok) {
1190 			fprintf (stderr,
1191 				"Warning: Bad CRC, using default environment\n");
1192 			memcpy(environment.data, default_environment, sizeof default_environment);
1193 		}
1194 	} else {
1195 		flag0 = *environment.flags;
1196 
1197 		dev_current = 1;
1198 		addr1 = calloc(1, CUR_ENVSIZE);
1199 		if (addr1 == NULL) {
1200 			fprintf(stderr,
1201 				"Not enough memory for environment (%ld bytes)\n",
1202 				CUR_ENVSIZE);
1203 			return -1;
1204 		}
1205 		redundant = addr1;
1206 
1207 		/*
1208 		 * have to set environment.image for flash_read(), careful -
1209 		 * other pointers in environment still point inside addr0
1210 		 */
1211 		environment.image = addr1;
1212 		if (flash_io (O_RDONLY))
1213 			return -1;
1214 
1215 		/* Check flag scheme compatibility */
1216 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1217 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1218 			environment.flag_scheme = FLAG_BOOLEAN;
1219 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1220 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1221 			environment.flag_scheme = FLAG_INCREMENTAL;
1222 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1223 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1224 			environment.flag_scheme = FLAG_BOOLEAN;
1225 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1226 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1227 			environment.flag_scheme = FLAG_INCREMENTAL;
1228 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1229 			   DEVTYPE(!dev_current) == MTD_ABSENT) {
1230 			environment.flag_scheme = FLAG_INCREMENTAL;
1231 		} else {
1232 			fprintf (stderr, "Incompatible flash types!\n");
1233 			return -1;
1234 		}
1235 
1236 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1237 
1238 		if (common_args.aes_flag) {
1239 			ret = env_aes_cbc_crypt(redundant->data, 0);
1240 			if (ret)
1241 				return ret;
1242 		}
1243 
1244 		crc1_ok = (crc1 == redundant->crc);
1245 		flag1 = redundant->flags;
1246 
1247 		if (crc0_ok && !crc1_ok) {
1248 			dev_current = 0;
1249 		} else if (!crc0_ok && crc1_ok) {
1250 			dev_current = 1;
1251 		} else if (!crc0_ok && !crc1_ok) {
1252 			fprintf (stderr,
1253 				"Warning: Bad CRC, using default environment\n");
1254 			memcpy (environment.data, default_environment,
1255 				sizeof default_environment);
1256 			dev_current = 0;
1257 		} else {
1258 			switch (environment.flag_scheme) {
1259 			case FLAG_BOOLEAN:
1260 				if (flag0 == active_flag &&
1261 				    flag1 == obsolete_flag) {
1262 					dev_current = 0;
1263 				} else if (flag0 == obsolete_flag &&
1264 					   flag1 == active_flag) {
1265 					dev_current = 1;
1266 				} else if (flag0 == flag1) {
1267 					dev_current = 0;
1268 				} else if (flag0 == 0xFF) {
1269 					dev_current = 0;
1270 				} else if (flag1 == 0xFF) {
1271 					dev_current = 1;
1272 				} else {
1273 					dev_current = 0;
1274 				}
1275 				break;
1276 			case FLAG_INCREMENTAL:
1277 				if (flag0 == 255 && flag1 == 0)
1278 					dev_current = 1;
1279 				else if ((flag1 == 255 && flag0 == 0) ||
1280 					 flag0 >= flag1)
1281 					dev_current = 0;
1282 				else /* flag1 > flag0 */
1283 					dev_current = 1;
1284 				break;
1285 			default:
1286 				fprintf (stderr, "Unknown flag scheme %u \n",
1287 					 environment.flag_scheme);
1288 				return -1;
1289 			}
1290 		}
1291 
1292 		/*
1293 		 * If we are reading, we don't need the flag and the CRC any
1294 		 * more, if we are writing, we will re-calculate CRC and update
1295 		 * flags before writing out
1296 		 */
1297 		if (dev_current) {
1298 			environment.image	= addr1;
1299 			environment.crc		= &redundant->crc;
1300 			environment.flags	= &redundant->flags;
1301 			environment.data	= redundant->data;
1302 			free (addr0);
1303 		} else {
1304 			environment.image	= addr0;
1305 			/* Other pointers are already set */
1306 			free (addr1);
1307 		}
1308 #ifdef DEBUG
1309 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1310 #endif
1311 	}
1312 	return 0;
1313 }
1314 
1315 
1316 static int parse_config ()
1317 {
1318 	struct stat st;
1319 
1320 #if defined(CONFIG_FILE)
1321 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1322 	if (get_config(common_args.config_file)) {
1323 		fprintf(stderr, "Cannot parse config file '%s': %m\n",
1324 			common_args.config_file);
1325 		return -1;
1326 	}
1327 #else
1328 	DEVNAME (0) = DEVICE1_NAME;
1329 	DEVOFFSET (0) = DEVICE1_OFFSET;
1330 	ENVSIZE (0) = ENV1_SIZE;
1331 	/* Default values are: erase-size=env-size */
1332 	DEVESIZE (0) = ENVSIZE (0);
1333 	/* #sectors=env-size/erase-size (rounded up) */
1334 	ENVSECTORS (0) = (ENVSIZE(0) + DEVESIZE(0) - 1) / DEVESIZE(0);
1335 #ifdef DEVICE1_ESIZE
1336 	DEVESIZE (0) = DEVICE1_ESIZE;
1337 #endif
1338 #ifdef DEVICE1_ENVSECTORS
1339 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1340 #endif
1341 
1342 #ifdef HAVE_REDUND
1343 	DEVNAME (1) = DEVICE2_NAME;
1344 	DEVOFFSET (1) = DEVICE2_OFFSET;
1345 	ENVSIZE (1) = ENV2_SIZE;
1346 	/* Default values are: erase-size=env-size */
1347 	DEVESIZE (1) = ENVSIZE (1);
1348 	/* #sectors=env-size/erase-size (rounded up) */
1349 	ENVSECTORS (1) = (ENVSIZE(1) + DEVESIZE(1) - 1) / DEVESIZE(1);
1350 #ifdef DEVICE2_ESIZE
1351 	DEVESIZE (1) = DEVICE2_ESIZE;
1352 #endif
1353 #ifdef DEVICE2_ENVSECTORS
1354 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1355 #endif
1356 	HaveRedundEnv = 1;
1357 #endif
1358 #endif
1359 	if (stat (DEVNAME (0), &st)) {
1360 		fprintf (stderr,
1361 			"Cannot access MTD device %s: %s\n",
1362 			DEVNAME (0), strerror (errno));
1363 		return -1;
1364 	}
1365 
1366 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1367 		fprintf (stderr,
1368 			"Cannot access MTD device %s: %s\n",
1369 			DEVNAME (1), strerror (errno));
1370 		return -1;
1371 	}
1372 	return 0;
1373 }
1374 
1375 #if defined(CONFIG_FILE)
1376 static int get_config (char *fname)
1377 {
1378 	FILE *fp;
1379 	int i = 0;
1380 	int rc;
1381 	char dump[128];
1382 	char *devname;
1383 
1384 	fp = fopen (fname, "r");
1385 	if (fp == NULL)
1386 		return -1;
1387 
1388 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1389 		/* Skip incomplete conversions and comment strings */
1390 		if (dump[0] == '#')
1391 			continue;
1392 
1393 		rc = sscanf (dump, "%ms %lx %lx %lx %lx",
1394 			     &devname,
1395 			     &DEVOFFSET (i),
1396 			     &ENVSIZE (i),
1397 			     &DEVESIZE (i),
1398 			     &ENVSECTORS (i));
1399 
1400 		if (rc < 3)
1401 			continue;
1402 
1403 		DEVNAME(i) = devname;
1404 
1405 		if (rc < 4)
1406 			/* Assume the erase size is the same as the env-size */
1407 			DEVESIZE(i) = ENVSIZE(i);
1408 
1409 		if (rc < 5)
1410 			/* Assume enough env sectors to cover the environment */
1411 			ENVSECTORS (i) = (ENVSIZE(i) + DEVESIZE(i) - 1) / DEVESIZE(i);
1412 
1413 		i++;
1414 	}
1415 	fclose (fp);
1416 
1417 	HaveRedundEnv = i - 1;
1418 	if (!i) {			/* No valid entries found */
1419 		errno = EINVAL;
1420 		return -1;
1421 	} else
1422 		return 0;
1423 }
1424 #endif
1425