1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2000-2010
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  *
6  * (C) Copyright 2008
7  * Guennadi Liakhovetski, DENX Software Engineering, lg@denx.de.
8  */
9 
10 #define _GNU_SOURCE
11 
12 #include <compiler.h>
13 #include <env.h>
14 #include <errno.h>
15 #include <env_flags.h>
16 #include <fcntl.h>
17 #include <libgen.h>
18 #include <linux/fs.h>
19 #include <linux/stringify.h>
20 #include <ctype.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <stddef.h>
24 #include <string.h>
25 #include <sys/types.h>
26 #include <sys/ioctl.h>
27 #include <sys/stat.h>
28 #include <u-boot/crc.h>
29 #include <unistd.h>
30 #include <dirent.h>
31 
32 #ifdef MTD_OLD
33 # include <stdint.h>
34 # include <linux/mtd/mtd.h>
35 #else
36 # define  __user	/* nothing */
37 # include <mtd/mtd-user.h>
38 #endif
39 
40 #include <mtd/ubi-user.h>
41 
42 #include "fw_env_private.h"
43 #include "fw_env.h"
44 
45 struct env_opts default_opts = {
46 #ifdef CONFIG_FILE
47 	.config_file = CONFIG_FILE
48 #endif
49 };
50 
51 #define DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
52 
53 #define min(x, y) ({				\
54 	typeof(x) _min1 = (x);			\
55 	typeof(y) _min2 = (y);			\
56 	(void) (&_min1 == &_min2);		\
57 	_min1 < _min2 ? _min1 : _min2; })
58 
59 struct envdev_s {
60 	const char *devname;		/* Device name */
61 	long long devoff;		/* Device offset */
62 	ulong env_size;			/* environment size */
63 	ulong erase_size;		/* device erase size */
64 	ulong env_sectors;		/* number of environment sectors */
65 	uint8_t mtd_type;		/* type of the MTD device */
66 	int is_ubi;			/* set if we use UBI volume */
67 };
68 
69 static struct envdev_s envdevices[2] = {
70 	{
71 		.mtd_type = MTD_ABSENT,
72 	}, {
73 		.mtd_type = MTD_ABSENT,
74 	},
75 };
76 
77 static int dev_current;
78 
79 #define DEVNAME(i)    envdevices[(i)].devname
80 #define DEVOFFSET(i)  envdevices[(i)].devoff
81 #define ENVSIZE(i)    envdevices[(i)].env_size
82 #define DEVESIZE(i)   envdevices[(i)].erase_size
83 #define ENVSECTORS(i) envdevices[(i)].env_sectors
84 #define DEVTYPE(i)    envdevices[(i)].mtd_type
85 #define IS_UBI(i)     envdevices[(i)].is_ubi
86 
87 #define CUR_ENVSIZE ENVSIZE(dev_current)
88 
89 static unsigned long usable_envsize;
90 #define ENV_SIZE      usable_envsize
91 
92 struct env_image_single {
93 	uint32_t crc;		/* CRC32 over data bytes    */
94 	char data[];
95 };
96 
97 struct env_image_redundant {
98 	uint32_t crc;		/* CRC32 over data bytes    */
99 	unsigned char flags;	/* active or obsolete */
100 	char data[];
101 };
102 
103 enum flag_scheme {
104 	FLAG_NONE,
105 	FLAG_BOOLEAN,
106 	FLAG_INCREMENTAL,
107 };
108 
109 struct environment {
110 	void *image;
111 	uint32_t *crc;
112 	unsigned char *flags;
113 	char *data;
114 	enum flag_scheme flag_scheme;
115 	int dirty;
116 };
117 
118 static struct environment environment = {
119 	.flag_scheme = FLAG_NONE,
120 };
121 
122 static int have_redund_env;
123 
124 #define DEFAULT_ENV_INSTANCE_STATIC
125 #include <env_default.h>
126 
127 #define UBI_DEV_START "/dev/ubi"
128 #define UBI_SYSFS "/sys/class/ubi"
129 #define UBI_VOL_NAME_PATT "ubi%d_%d"
130 
is_ubi_devname(const char * devname)131 static int is_ubi_devname(const char *devname)
132 {
133 	return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
134 }
135 
ubi_check_volume_sysfs_name(const char * volume_sysfs_name,const char * volname)136 static int ubi_check_volume_sysfs_name(const char *volume_sysfs_name,
137 				       const char *volname)
138 {
139 	char path[256];
140 	FILE *file;
141 	char *name;
142 	int ret;
143 
144 	strcpy(path, UBI_SYSFS "/");
145 	strcat(path, volume_sysfs_name);
146 	strcat(path, "/name");
147 
148 	file = fopen(path, "r");
149 	if (!file)
150 		return -1;
151 
152 	ret = fscanf(file, "%ms", &name);
153 	fclose(file);
154 	if (ret <= 0 || !name) {
155 		fprintf(stderr,
156 			"Failed to read from file %s, ret = %d, name = %s\n",
157 			path, ret, name);
158 		return -1;
159 	}
160 
161 	if (!strcmp(name, volname)) {
162 		free(name);
163 		return 0;
164 	}
165 	free(name);
166 
167 	return -1;
168 }
169 
ubi_get_volnum_by_name(int devnum,const char * volname)170 static int ubi_get_volnum_by_name(int devnum, const char *volname)
171 {
172 	DIR *sysfs_ubi;
173 	struct dirent *dirent;
174 	int ret;
175 	int tmp_devnum;
176 	int volnum;
177 
178 	sysfs_ubi = opendir(UBI_SYSFS);
179 	if (!sysfs_ubi)
180 		return -1;
181 
182 #ifdef DEBUG
183 	fprintf(stderr, "Looking for volume name \"%s\"\n", volname);
184 #endif
185 
186 	while (1) {
187 		dirent = readdir(sysfs_ubi);
188 		if (!dirent)
189 			return -1;
190 
191 		ret = sscanf(dirent->d_name, UBI_VOL_NAME_PATT,
192 			     &tmp_devnum, &volnum);
193 		if (ret == 2 && devnum == tmp_devnum) {
194 			if (ubi_check_volume_sysfs_name(dirent->d_name,
195 							volname) == 0)
196 				return volnum;
197 		}
198 	}
199 
200 	return -1;
201 }
202 
ubi_get_devnum_by_devname(const char * devname)203 static int ubi_get_devnum_by_devname(const char *devname)
204 {
205 	int devnum;
206 	int ret;
207 
208 	ret = sscanf(devname + sizeof(UBI_DEV_START) - 1, "%d", &devnum);
209 	if (ret != 1)
210 		return -1;
211 
212 	return devnum;
213 }
214 
ubi_get_volume_devname(const char * devname,const char * volname)215 static const char *ubi_get_volume_devname(const char *devname,
216 					  const char *volname)
217 {
218 	char *volume_devname;
219 	int volnum;
220 	int devnum;
221 	int ret;
222 
223 	devnum = ubi_get_devnum_by_devname(devname);
224 	if (devnum < 0)
225 		return NULL;
226 
227 	volnum = ubi_get_volnum_by_name(devnum, volname);
228 	if (volnum < 0)
229 		return NULL;
230 
231 	ret = asprintf(&volume_devname, "%s_%d", devname, volnum);
232 	if (ret < 0)
233 		return NULL;
234 
235 #ifdef DEBUG
236 	fprintf(stderr, "Found ubi volume \"%s:%s\" -> %s\n",
237 		devname, volname, volume_devname);
238 #endif
239 
240 	return volume_devname;
241 }
242 
ubi_check_dev(unsigned int dev_id)243 static void ubi_check_dev(unsigned int dev_id)
244 {
245 	char *devname = (char *)DEVNAME(dev_id);
246 	char *pname;
247 	const char *volname = NULL;
248 	const char *volume_devname;
249 
250 	if (!is_ubi_devname(DEVNAME(dev_id)))
251 		return;
252 
253 	IS_UBI(dev_id) = 1;
254 
255 	for (pname = devname; *pname != '\0'; pname++) {
256 		if (*pname == ':') {
257 			*pname = '\0';
258 			volname = pname + 1;
259 			break;
260 		}
261 	}
262 
263 	if (volname) {
264 		/* Let's find real volume device name */
265 		volume_devname = ubi_get_volume_devname(devname, volname);
266 		if (!volume_devname) {
267 			fprintf(stderr, "Didn't found ubi volume \"%s\"\n",
268 				volname);
269 			return;
270 		}
271 
272 		free(devname);
273 		DEVNAME(dev_id) = volume_devname;
274 	}
275 }
276 
ubi_update_start(int fd,int64_t bytes)277 static int ubi_update_start(int fd, int64_t bytes)
278 {
279 	if (ioctl(fd, UBI_IOCVOLUP, &bytes))
280 		return -1;
281 	return 0;
282 }
283 
ubi_read(int fd,void * buf,size_t count)284 static int ubi_read(int fd, void *buf, size_t count)
285 {
286 	ssize_t ret;
287 
288 	while (count > 0) {
289 		ret = read(fd, buf, count);
290 		if (ret > 0) {
291 			count -= ret;
292 			buf += ret;
293 
294 			continue;
295 		}
296 
297 		if (ret == 0) {
298 			/*
299 			 * Happens in case of too short volume data size. If we
300 			 * return error status we will fail it will be treated
301 			 * as UBI device error.
302 			 *
303 			 * Leave catching this error to CRC check.
304 			 */
305 			fprintf(stderr, "Warning: end of data on ubi volume\n");
306 			return 0;
307 		} else if (errno == EBADF) {
308 			/*
309 			 * Happens in case of corrupted volume. The same as
310 			 * above, we cannot return error now, as we will still
311 			 * be able to successfully write environment later.
312 			 */
313 			fprintf(stderr, "Warning: corrupted volume?\n");
314 			return 0;
315 		} else if (errno == EINTR) {
316 			continue;
317 		}
318 
319 		fprintf(stderr, "Cannot read %u bytes from ubi volume, %s\n",
320 			(unsigned int)count, strerror(errno));
321 		return -1;
322 	}
323 
324 	return 0;
325 }
326 
ubi_write(int fd,const void * buf,size_t count)327 static int ubi_write(int fd, const void *buf, size_t count)
328 {
329 	ssize_t ret;
330 
331 	while (count > 0) {
332 		ret = write(fd, buf, count);
333 		if (ret <= 0) {
334 			if (ret < 0 && errno == EINTR)
335 				continue;
336 
337 			fprintf(stderr, "Cannot write %u bytes to ubi volume\n",
338 				(unsigned int)count);
339 			return -1;
340 		}
341 
342 		count -= ret;
343 		buf += ret;
344 	}
345 
346 	return 0;
347 }
348 
349 static int flash_io(int mode);
350 static int parse_config(struct env_opts *opts);
351 
352 #if defined(CONFIG_FILE)
353 static int get_config(char *);
354 #endif
355 
skip_chars(char * s)356 static char *skip_chars(char *s)
357 {
358 	for (; *s != '\0'; s++) {
359 		if (isblank(*s) || *s == '=')
360 			return s;
361 	}
362 	return NULL;
363 }
364 
skip_blanks(char * s)365 static char *skip_blanks(char *s)
366 {
367 	for (; *s != '\0'; s++) {
368 		if (!isblank(*s))
369 			return s;
370 	}
371 	return NULL;
372 }
373 
374 /*
375  * s1 is either a simple 'name', or a 'name=value' pair.
376  * s2 is a 'name=value' pair.
377  * If the names match, return the value of s2, else NULL.
378  */
envmatch(char * s1,char * s2)379 static char *envmatch(char *s1, char *s2)
380 {
381 	if (s1 == NULL || s2 == NULL)
382 		return NULL;
383 
384 	while (*s1 == *s2++)
385 		if (*s1++ == '=')
386 			return s2;
387 	if (*s1 == '\0' && *(s2 - 1) == '=')
388 		return s2;
389 	return NULL;
390 }
391 
392 /**
393  * Search the environment for a variable.
394  * Return the value, if found, or NULL, if not found.
395  */
fw_getenv(char * name)396 char *fw_getenv(char *name)
397 {
398 	char *env, *nxt;
399 
400 	for (env = environment.data; *env; env = nxt + 1) {
401 		char *val;
402 
403 		for (nxt = env; *nxt; ++nxt) {
404 			if (nxt >= &environment.data[ENV_SIZE]) {
405 				fprintf(stderr, "## Error: "
406 					"environment not terminated\n");
407 				return NULL;
408 			}
409 		}
410 		val = envmatch(name, env);
411 		if (!val)
412 			continue;
413 		return val;
414 	}
415 	return NULL;
416 }
417 
418 /*
419  * Search the default environment for a variable.
420  * Return the value, if found, or NULL, if not found.
421  */
fw_getdefenv(char * name)422 char *fw_getdefenv(char *name)
423 {
424 	char *env, *nxt;
425 
426 	for (env = default_environment; *env; env = nxt + 1) {
427 		char *val;
428 
429 		for (nxt = env; *nxt; ++nxt) {
430 			if (nxt >= &default_environment[ENV_SIZE]) {
431 				fprintf(stderr, "## Error: "
432 					"default environment not terminated\n");
433 				return NULL;
434 			}
435 		}
436 		val = envmatch(name, env);
437 		if (!val)
438 			continue;
439 		return val;
440 	}
441 	return NULL;
442 }
443 
444 /*
445  * Print the current definition of one, or more, or all
446  * environment variables
447  */
fw_printenv(int argc,char * argv[],int value_only,struct env_opts * opts)448 int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts)
449 {
450 	int i, rc = 0;
451 
452 	if (value_only && argc != 1) {
453 		fprintf(stderr,
454 			"## Error: `-n'/`--noheader' option requires exactly one argument\n");
455 		return -1;
456 	}
457 
458 	if (!opts)
459 		opts = &default_opts;
460 
461 	if (fw_env_open(opts))
462 		return -1;
463 
464 	if (argc == 0) {	/* Print all env variables  */
465 		char *env, *nxt;
466 		for (env = environment.data; *env; env = nxt + 1) {
467 			for (nxt = env; *nxt; ++nxt) {
468 				if (nxt >= &environment.data[ENV_SIZE]) {
469 					fprintf(stderr, "## Error: "
470 						"environment not terminated\n");
471 					return -1;
472 				}
473 			}
474 
475 			printf("%s\n", env);
476 		}
477 		fw_env_close(opts);
478 		return 0;
479 	}
480 
481 	for (i = 0; i < argc; ++i) {	/* print a subset of env variables */
482 		char *name = argv[i];
483 		char *val = NULL;
484 
485 		val = fw_getenv(name);
486 		if (!val) {
487 			fprintf(stderr, "## Error: \"%s\" not defined\n", name);
488 			rc = -1;
489 			continue;
490 		}
491 
492 		if (value_only) {
493 			puts(val);
494 			break;
495 		}
496 
497 		printf("%s=%s\n", name, val);
498 	}
499 
500 	fw_env_close(opts);
501 
502 	return rc;
503 }
504 
fw_env_flush(struct env_opts * opts)505 int fw_env_flush(struct env_opts *opts)
506 {
507 	if (!opts)
508 		opts = &default_opts;
509 
510 	if (!environment.dirty)
511 		return 0;
512 
513 	/*
514 	 * Update CRC
515 	 */
516 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
517 
518 	/* write environment back to flash */
519 	if (flash_io(O_RDWR)) {
520 		fprintf(stderr, "Error: can't write fw_env to flash\n");
521 		return -1;
522 	}
523 
524 	return 0;
525 }
526 
527 /*
528  * Set/Clear a single variable in the environment.
529  * This is called in sequence to update the environment
530  * in RAM without updating the copy in flash after each set
531  */
fw_env_write(char * name,char * value)532 int fw_env_write(char *name, char *value)
533 {
534 	int len;
535 	char *env, *nxt;
536 	char *oldval = NULL;
537 	int deleting, creating, overwriting;
538 
539 	/*
540 	 * search if variable with this name already exists
541 	 */
542 	for (nxt = env = environment.data; *env; env = nxt + 1) {
543 		for (nxt = env; *nxt; ++nxt) {
544 			if (nxt >= &environment.data[ENV_SIZE]) {
545 				fprintf(stderr, "## Error: "
546 					"environment not terminated\n");
547 				errno = EINVAL;
548 				return -1;
549 			}
550 		}
551 		oldval = envmatch(name, env);
552 		if (oldval)
553 			break;
554 	}
555 
556 	deleting = (oldval && !(value && strlen(value)));
557 	creating = (!oldval && (value && strlen(value)));
558 	overwriting = (oldval && (value && strlen(value) &&
559 				  strcmp(oldval, value)));
560 
561 	/* check for permission */
562 	if (deleting) {
563 		if (env_flags_validate_varaccess(name,
564 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
565 			printf("Can't delete \"%s\"\n", name);
566 			errno = EROFS;
567 			return -1;
568 		}
569 	} else if (overwriting) {
570 		if (env_flags_validate_varaccess(name,
571 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
572 			printf("Can't overwrite \"%s\"\n", name);
573 			errno = EROFS;
574 			return -1;
575 		} else if (env_flags_validate_varaccess(name,
576 			   ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
577 			const char *defval = fw_getdefenv(name);
578 
579 			if (defval == NULL)
580 				defval = "";
581 			if (strcmp(oldval, defval)
582 			    != 0) {
583 				printf("Can't overwrite \"%s\"\n", name);
584 				errno = EROFS;
585 				return -1;
586 			}
587 		}
588 	} else if (creating) {
589 		if (env_flags_validate_varaccess(name,
590 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
591 			printf("Can't create \"%s\"\n", name);
592 			errno = EROFS;
593 			return -1;
594 		}
595 	} else
596 		/* Nothing to do */
597 		return 0;
598 
599 	environment.dirty = 1;
600 	if (deleting || overwriting) {
601 		if (*++nxt == '\0') {
602 			*env = '\0';
603 		} else {
604 			for (;;) {
605 				*env = *nxt++;
606 				if ((*env == '\0') && (*nxt == '\0'))
607 					break;
608 				++env;
609 			}
610 		}
611 		*++env = '\0';
612 	}
613 
614 	/* Delete only ? */
615 	if (!value || !strlen(value))
616 		return 0;
617 
618 	/*
619 	 * Append new definition at the end
620 	 */
621 	for (env = environment.data; *env || *(env + 1); ++env)
622 		;
623 	if (env > environment.data)
624 		++env;
625 	/*
626 	 * Overflow when:
627 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
628 	 */
629 	len = strlen(name) + 2;
630 	/* add '=' for first arg, ' ' for all others */
631 	len += strlen(value) + 1;
632 
633 	if (len > (&environment.data[ENV_SIZE] - env)) {
634 		fprintf(stderr,
635 			"Error: environment overflow, \"%s\" deleted\n", name);
636 		return -1;
637 	}
638 
639 	while ((*env = *name++) != '\0')
640 		env++;
641 	*env = '=';
642 	while ((*++env = *value++) != '\0')
643 		;
644 
645 	/* end is marked with double '\0' */
646 	*++env = '\0';
647 
648 	return 0;
649 }
650 
651 /*
652  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
653  * 0	  - OK
654  * EINVAL - need at least 1 argument
655  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
656  *	    modified or deleted
657  *
658  */
fw_env_set(int argc,char * argv[],struct env_opts * opts)659 int fw_env_set(int argc, char *argv[], struct env_opts *opts)
660 {
661 	int i;
662 	size_t len;
663 	char *name, **valv;
664 	char *oldval;
665 	char *value = NULL;
666 	int valc;
667 	int ret;
668 
669 	if (!opts)
670 		opts = &default_opts;
671 
672 	if (argc < 1) {
673 		fprintf(stderr, "## Error: variable name missing\n");
674 		errno = EINVAL;
675 		return -1;
676 	}
677 
678 	if (fw_env_open(opts)) {
679 		fprintf(stderr, "Error: environment not initialized\n");
680 		return -1;
681 	}
682 
683 	name = argv[0];
684 	valv = argv + 1;
685 	valc = argc - 1;
686 
687 	if (env_flags_validate_env_set_params(name, valv, valc) < 0) {
688 		fw_env_close(opts);
689 		return -1;
690 	}
691 
692 	len = 0;
693 	for (i = 0; i < valc; ++i) {
694 		char *val = valv[i];
695 		size_t val_len = strlen(val);
696 
697 		if (value)
698 			value[len - 1] = ' ';
699 		oldval = value;
700 		value = realloc(value, len + val_len + 1);
701 		if (!value) {
702 			fprintf(stderr,
703 				"Cannot malloc %zu bytes: %s\n",
704 				len, strerror(errno));
705 			free(oldval);
706 			return -1;
707 		}
708 
709 		memcpy(value + len, val, val_len);
710 		len += val_len;
711 		value[len++] = '\0';
712 	}
713 
714 	fw_env_write(name, value);
715 
716 	free(value);
717 
718 	ret = fw_env_flush(opts);
719 	fw_env_close(opts);
720 
721 	return ret;
722 }
723 
724 /*
725  * Parse  a file  and configure the u-boot variables.
726  * The script file has a very simple format, as follows:
727  *
728  * Each line has a couple with name, value:
729  * <white spaces>variable_name<white spaces>variable_value
730  *
731  * Both variable_name and variable_value are interpreted as strings.
732  * Any character after <white spaces> and before ending \r\n is interpreted
733  * as variable's value (no comment allowed on these lines !)
734  *
735  * Comments are allowed if the first character in the line is #
736  *
737  * Returns -1 and sets errno error codes:
738  * 0	  - OK
739  * -1     - Error
740  */
fw_parse_script(char * fname,struct env_opts * opts)741 int fw_parse_script(char *fname, struct env_opts *opts)
742 {
743 	FILE *fp;
744 	char *line = NULL;
745 	size_t linesize = 0;
746 	char *name;
747 	char *val;
748 	int lineno = 0;
749 	int len;
750 	int ret = 0;
751 
752 	if (!opts)
753 		opts = &default_opts;
754 
755 	if (fw_env_open(opts)) {
756 		fprintf(stderr, "Error: environment not initialized\n");
757 		return -1;
758 	}
759 
760 	if (strcmp(fname, "-") == 0)
761 		fp = stdin;
762 	else {
763 		fp = fopen(fname, "r");
764 		if (fp == NULL) {
765 			fprintf(stderr, "I cannot open %s for reading\n",
766 				fname);
767 			return -1;
768 		}
769 	}
770 
771 	while ((len = getline(&line, &linesize, fp)) != -1) {
772 		lineno++;
773 
774 		/*
775 		 * Read a whole line from the file. If the line is not
776 		 * terminated, reports an error and exit.
777 		 */
778 		if (line[len - 1] != '\n') {
779 			fprintf(stderr,
780 				"Line %d not correctly terminated\n",
781 				lineno);
782 			ret = -1;
783 			break;
784 		}
785 
786 		/* Drop ending line feed / carriage return */
787 		line[--len] = '\0';
788 		if (len && line[len - 1] == '\r')
789 			line[--len] = '\0';
790 
791 		/* Skip comment or empty lines */
792 		if (len == 0 || line[0] == '#')
793 			continue;
794 
795 		/*
796 		 * Search for variable's name remove leading whitespaces
797 		 */
798 		name = skip_blanks(line);
799 		if (!name)
800 			continue;
801 
802 		/* The first white space is the end of variable name */
803 		val = skip_chars(name);
804 		len = strlen(name);
805 		if (val) {
806 			*val++ = '\0';
807 			if ((val - name) < len)
808 				val = skip_blanks(val);
809 			else
810 				val = NULL;
811 		}
812 #ifdef DEBUG
813 		fprintf(stderr, "Setting %s : %s\n",
814 			name, val ? val : " removed");
815 #endif
816 
817 		if (env_flags_validate_type(name, val) < 0) {
818 			ret = -1;
819 			break;
820 		}
821 
822 		/*
823 		 * If there is an error setting a variable,
824 		 * try to save the environment and returns an error
825 		 */
826 		if (fw_env_write(name, val)) {
827 			fprintf(stderr,
828 				"fw_env_write returns with error : %s\n",
829 				strerror(errno));
830 			ret = -1;
831 			break;
832 		}
833 
834 	}
835 	free(line);
836 
837 	/* Close file if not stdin */
838 	if (strcmp(fname, "-") != 0)
839 		fclose(fp);
840 
841 	ret |= fw_env_flush(opts);
842 
843 	fw_env_close(opts);
844 
845 	return ret;
846 }
847 
848 /**
849  * environment_end() - compute offset of first byte right after environment
850  * @dev - index of enviroment buffer
851  * Return:
852  *  device offset of first byte right after environment
853  */
environment_end(int dev)854 off_t environment_end(int dev)
855 {
856 	/* environment is block aligned */
857 	return DEVOFFSET(dev) + ENVSECTORS(dev) * DEVESIZE(dev);
858 }
859 
860 /*
861  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
862  * 0	- block is good
863  * > 0	- block is bad
864  * < 0	- failed to test
865  */
flash_bad_block(int fd,uint8_t mtd_type,loff_t blockstart)866 static int flash_bad_block(int fd, uint8_t mtd_type, loff_t blockstart)
867 {
868 	if (mtd_type == MTD_NANDFLASH) {
869 		int badblock = ioctl(fd, MEMGETBADBLOCK, &blockstart);
870 
871 		if (badblock < 0) {
872 			perror("Cannot read bad block mark");
873 			return badblock;
874 		}
875 
876 		if (badblock) {
877 #ifdef DEBUG
878 			fprintf(stderr, "Bad block at 0x%llx, skipping\n",
879 				(unsigned long long)blockstart);
880 #endif
881 			return badblock;
882 		}
883 	}
884 
885 	return 0;
886 }
887 
888 /*
889  * Read data from flash at an offset into a provided buffer. On NAND it skips
890  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
891  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
892  */
flash_read_buf(int dev,int fd,void * buf,size_t count,off_t offset)893 static int flash_read_buf(int dev, int fd, void *buf, size_t count,
894 			  off_t offset)
895 {
896 	size_t blocklen;	/* erase / write length - one block on NAND,
897 				   0 on NOR */
898 	size_t processed = 0;	/* progress counter */
899 	size_t readlen = count;	/* current read length */
900 	off_t block_seek;	/* offset inside the current block to the start
901 				   of the data */
902 	loff_t blockstart;	/* running start of the current block -
903 				   MEMGETBADBLOCK needs 64 bits */
904 	int rc;
905 
906 	blockstart = (offset / DEVESIZE(dev)) * DEVESIZE(dev);
907 
908 	/* Offset inside a block */
909 	block_seek = offset - blockstart;
910 
911 	if (DEVTYPE(dev) == MTD_NANDFLASH) {
912 		/*
913 		 * NAND: calculate which blocks we are reading. We have
914 		 * to read one block at a time to skip bad blocks.
915 		 */
916 		blocklen = DEVESIZE(dev);
917 
918 		/* Limit to one block for the first read */
919 		if (readlen > blocklen - block_seek)
920 			readlen = blocklen - block_seek;
921 	} else {
922 		blocklen = 0;
923 	}
924 
925 	/* This only runs once on NOR flash */
926 	while (processed < count) {
927 		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
928 		if (rc < 0)	/* block test failed */
929 			return -1;
930 
931 		if (blockstart + block_seek + readlen > environment_end(dev)) {
932 			/* End of range is reached */
933 			fprintf(stderr, "Too few good blocks within range\n");
934 			return -1;
935 		}
936 
937 		if (rc) {	/* block is bad */
938 			blockstart += blocklen;
939 			continue;
940 		}
941 
942 		/*
943 		 * If a block is bad, we retry in the next block at the same
944 		 * offset - see env/nand.c::writeenv()
945 		 */
946 		lseek(fd, blockstart + block_seek, SEEK_SET);
947 
948 		rc = read(fd, buf + processed, readlen);
949 		if (rc == -1) {
950 			fprintf(stderr, "Read error on %s: %s\n",
951 				DEVNAME(dev), strerror(errno));
952 			return -1;
953 		}
954 #ifdef DEBUG
955 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
956 			rc, (unsigned long long)blockstart + block_seek,
957 			DEVNAME(dev));
958 #endif
959 		processed += rc;
960 		if (rc != readlen) {
961 			fprintf(stderr,
962 				"Warning on %s: Attempted to read %zd bytes but got %d\n",
963 				DEVNAME(dev), readlen, rc);
964 			readlen -= rc;
965 			block_seek += rc;
966 		} else {
967 			blockstart += blocklen;
968 			readlen = min(blocklen, count - processed);
969 			block_seek = 0;
970 		}
971 	}
972 
973 	return processed;
974 }
975 
976 /*
977  * Write count bytes from begin of environment, but stay within
978  * ENVSECTORS(dev) sectors of
979  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
980  * erase and write the whole data at once.
981  */
flash_write_buf(int dev,int fd,void * buf,size_t count)982 static int flash_write_buf(int dev, int fd, void *buf, size_t count)
983 {
984 	void *data;
985 	struct erase_info_user erase;
986 	size_t blocklen;	/* length of NAND block / NOR erase sector */
987 	size_t erase_len;	/* whole area that can be erased - may include
988 				   bad blocks */
989 	size_t erasesize;	/* erase / write length - one block on NAND,
990 				   whole area on NOR */
991 	size_t processed = 0;	/* progress counter */
992 	size_t write_total;	/* total size to actually write - excluding
993 				   bad blocks */
994 	off_t erase_offset;	/* offset to the first erase block (aligned)
995 				   below offset */
996 	off_t block_seek;	/* offset inside the erase block to the start
997 				   of the data */
998 	loff_t blockstart;	/* running start of the current block -
999 				   MEMGETBADBLOCK needs 64 bits */
1000 	int was_locked = 0;	/* flash lock flag */
1001 	int rc;
1002 
1003 	/*
1004 	 * For mtd devices only offset and size of the environment do matter
1005 	 */
1006 	if (DEVTYPE(dev) == MTD_ABSENT) {
1007 		blocklen = count;
1008 		erase_len = blocklen;
1009 		blockstart = DEVOFFSET(dev);
1010 		block_seek = 0;
1011 		write_total = blocklen;
1012 	} else {
1013 		blocklen = DEVESIZE(dev);
1014 
1015 		erase_offset = DEVOFFSET(dev);
1016 
1017 		/* Maximum area we may use */
1018 		erase_len = environment_end(dev) - erase_offset;
1019 
1020 		blockstart = erase_offset;
1021 
1022 		/* Offset inside a block */
1023 		block_seek = DEVOFFSET(dev) - erase_offset;
1024 
1025 		/*
1026 		 * Data size we actually write: from the start of the block
1027 		 * to the start of the data, then count bytes of data, and
1028 		 * to the end of the block
1029 		 */
1030 		write_total = ((block_seek + count + blocklen - 1) /
1031 			       blocklen) * blocklen;
1032 	}
1033 
1034 	/*
1035 	 * Support data anywhere within erase sectors: read out the complete
1036 	 * area to be erased, replace the environment image, write the whole
1037 	 * block back again.
1038 	 */
1039 	if (write_total > count) {
1040 		data = malloc(erase_len);
1041 		if (!data) {
1042 			fprintf(stderr,
1043 				"Cannot malloc %zu bytes: %s\n",
1044 				erase_len, strerror(errno));
1045 			return -1;
1046 		}
1047 
1048 		rc = flash_read_buf(dev, fd, data, write_total, erase_offset);
1049 		if (write_total != rc)
1050 			return -1;
1051 
1052 #ifdef DEBUG
1053 		fprintf(stderr, "Preserving data ");
1054 		if (block_seek != 0)
1055 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
1056 		if (block_seek + count != write_total) {
1057 			if (block_seek != 0)
1058 				fprintf(stderr, " and ");
1059 			fprintf(stderr, "0x%lx - 0x%lx",
1060 				(unsigned long)block_seek + count,
1061 				(unsigned long)write_total - 1);
1062 		}
1063 		fprintf(stderr, "\n");
1064 #endif
1065 		/* Overwrite the old environment */
1066 		memcpy(data + block_seek, buf, count);
1067 	} else {
1068 		/*
1069 		 * We get here, iff offset is block-aligned and count is a
1070 		 * multiple of blocklen - see write_total calculation above
1071 		 */
1072 		data = buf;
1073 	}
1074 
1075 	if (DEVTYPE(dev) == MTD_NANDFLASH) {
1076 		/*
1077 		 * NAND: calculate which blocks we are writing. We have
1078 		 * to write one block at a time to skip bad blocks.
1079 		 */
1080 		erasesize = blocklen;
1081 	} else {
1082 		erasesize = erase_len;
1083 	}
1084 
1085 	erase.length = erasesize;
1086 	if (DEVTYPE(dev) != MTD_ABSENT) {
1087 		was_locked = ioctl(fd, MEMISLOCKED, &erase);
1088 		/* treat any errors as unlocked flash */
1089 		if (was_locked < 0)
1090 			was_locked = 0;
1091 	}
1092 
1093 	/* This only runs once on NOR flash and SPI-dataflash */
1094 	while (processed < write_total) {
1095 		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
1096 		if (rc < 0)	/* block test failed */
1097 			return rc;
1098 
1099 		if (blockstart + erasesize > environment_end(dev)) {
1100 			fprintf(stderr, "End of range reached, aborting\n");
1101 			return -1;
1102 		}
1103 
1104 		if (rc) {	/* block is bad */
1105 			blockstart += blocklen;
1106 			continue;
1107 		}
1108 
1109 		if (DEVTYPE(dev) != MTD_ABSENT) {
1110 			erase.start = blockstart;
1111 			if (was_locked)
1112 				ioctl(fd, MEMUNLOCK, &erase);
1113 			/* These do not need an explicit erase cycle */
1114 			if (DEVTYPE(dev) != MTD_DATAFLASH)
1115 				if (ioctl(fd, MEMERASE, &erase) != 0) {
1116 					fprintf(stderr,
1117 						"MTD erase error on %s: %s\n",
1118 						DEVNAME(dev), strerror(errno));
1119 					return -1;
1120 				}
1121 		}
1122 
1123 		if (lseek(fd, blockstart, SEEK_SET) == -1) {
1124 			fprintf(stderr,
1125 				"Seek error on %s: %s\n",
1126 				DEVNAME(dev), strerror(errno));
1127 			return -1;
1128 		}
1129 #ifdef DEBUG
1130 		fprintf(stderr, "Write 0x%llx bytes at 0x%llx\n",
1131 			(unsigned long long)erasesize,
1132 			(unsigned long long)blockstart);
1133 #endif
1134 		if (write(fd, data + processed, erasesize) != erasesize) {
1135 			fprintf(stderr, "Write error on %s: %s\n",
1136 				DEVNAME(dev), strerror(errno));
1137 			return -1;
1138 		}
1139 
1140 		if (DEVTYPE(dev) != MTD_ABSENT) {
1141 			if (was_locked)
1142 				ioctl(fd, MEMLOCK, &erase);
1143 		}
1144 
1145 		processed += erasesize;
1146 		block_seek = 0;
1147 		blockstart += erasesize;
1148 	}
1149 
1150 	if (write_total > count)
1151 		free(data);
1152 
1153 	return processed;
1154 }
1155 
1156 /*
1157  * Set obsolete flag at offset - NOR flash only
1158  */
flash_flag_obsolete(int dev,int fd,off_t offset)1159 static int flash_flag_obsolete(int dev, int fd, off_t offset)
1160 {
1161 	int rc;
1162 	struct erase_info_user erase;
1163 	char tmp = ENV_REDUND_OBSOLETE;
1164 	int was_locked;	/* flash lock flag */
1165 
1166 	was_locked = ioctl(fd, MEMISLOCKED, &erase);
1167 	erase.start = DEVOFFSET(dev);
1168 	erase.length = DEVESIZE(dev);
1169 	/* This relies on the fact, that ENV_REDUND_OBSOLETE == 0 */
1170 	rc = lseek(fd, offset, SEEK_SET);
1171 	if (rc < 0) {
1172 		fprintf(stderr, "Cannot seek to set the flag on %s\n",
1173 			DEVNAME(dev));
1174 		return rc;
1175 	}
1176 	if (was_locked)
1177 		ioctl(fd, MEMUNLOCK, &erase);
1178 	rc = write(fd, &tmp, sizeof(tmp));
1179 	if (was_locked)
1180 		ioctl(fd, MEMLOCK, &erase);
1181 	if (rc < 0)
1182 		perror("Could not set obsolete flag");
1183 
1184 	return rc;
1185 }
1186 
flash_write(int fd_current,int fd_target,int dev_target)1187 static int flash_write(int fd_current, int fd_target, int dev_target)
1188 {
1189 	int rc;
1190 
1191 	switch (environment.flag_scheme) {
1192 	case FLAG_NONE:
1193 		break;
1194 	case FLAG_INCREMENTAL:
1195 		(*environment.flags)++;
1196 		break;
1197 	case FLAG_BOOLEAN:
1198 		*environment.flags = ENV_REDUND_ACTIVE;
1199 		break;
1200 	default:
1201 		fprintf(stderr, "Unimplemented flash scheme %u\n",
1202 			environment.flag_scheme);
1203 		return -1;
1204 	}
1205 
1206 #ifdef DEBUG
1207 	fprintf(stderr, "Writing new environment at 0x%llx on %s\n",
1208 		DEVOFFSET(dev_target), DEVNAME(dev_target));
1209 #endif
1210 
1211 	if (IS_UBI(dev_target)) {
1212 		if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
1213 			return -1;
1214 		return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
1215 	}
1216 
1217 	rc = flash_write_buf(dev_target, fd_target, environment.image,
1218 			     CUR_ENVSIZE);
1219 	if (rc < 0)
1220 		return rc;
1221 
1222 	if (environment.flag_scheme == FLAG_BOOLEAN) {
1223 		/* Have to set obsolete flag */
1224 		off_t offset = DEVOFFSET(dev_current) +
1225 		    offsetof(struct env_image_redundant, flags);
1226 #ifdef DEBUG
1227 		fprintf(stderr,
1228 			"Setting obsolete flag in environment at 0x%llx on %s\n",
1229 			DEVOFFSET(dev_current), DEVNAME(dev_current));
1230 #endif
1231 		flash_flag_obsolete(dev_current, fd_current, offset);
1232 	}
1233 
1234 	return 0;
1235 }
1236 
flash_read(int fd)1237 static int flash_read(int fd)
1238 {
1239 	int rc;
1240 
1241 	if (IS_UBI(dev_current)) {
1242 		DEVTYPE(dev_current) = MTD_ABSENT;
1243 
1244 		return ubi_read(fd, environment.image, CUR_ENVSIZE);
1245 	}
1246 
1247 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1248 			    DEVOFFSET(dev_current));
1249 	if (rc != CUR_ENVSIZE)
1250 		return -1;
1251 
1252 	return 0;
1253 }
1254 
flash_open_tempfile(const char ** dname,const char ** target_temp)1255 static int flash_open_tempfile(const char **dname, const char **target_temp)
1256 {
1257 	char *dup_name = strdup(DEVNAME(dev_current));
1258 	char *temp_name = NULL;
1259 	int rc = -1;
1260 
1261 	if (!dup_name)
1262 		return -1;
1263 
1264 	*dname = dirname(dup_name);
1265 	if (!*dname)
1266 		goto err;
1267 
1268 	rc = asprintf(&temp_name, "%s/XXXXXX", *dname);
1269 	if (rc == -1)
1270 		goto err;
1271 
1272 	rc = mkstemp(temp_name);
1273 	if (rc == -1) {
1274 		/* fall back to in place write */
1275 		fprintf(stderr,
1276 			"Can't create %s: %s\n", temp_name, strerror(errno));
1277 		free(temp_name);
1278 	} else {
1279 		*target_temp = temp_name;
1280 		/* deliberately leak dup_name as dname /might/ point into
1281 		 * it and we need it for our caller
1282 		 */
1283 		dup_name = NULL;
1284 	}
1285 
1286 err:
1287 	if (dup_name)
1288 		free(dup_name);
1289 
1290 	return rc;
1291 }
1292 
flash_io_write(int fd_current)1293 static int flash_io_write(int fd_current)
1294 {
1295 	int fd_target = -1, rc, dev_target;
1296 	const char *dname, *target_temp = NULL;
1297 
1298 	if (have_redund_env) {
1299 		/* switch to next partition for writing */
1300 		dev_target = !dev_current;
1301 		/* dev_target: fd_target, erase_target */
1302 		fd_target = open(DEVNAME(dev_target), O_RDWR);
1303 		if (fd_target < 0) {
1304 			fprintf(stderr,
1305 				"Can't open %s: %s\n",
1306 				DEVNAME(dev_target), strerror(errno));
1307 			rc = -1;
1308 			goto exit;
1309 		}
1310 	} else {
1311 		struct stat sb;
1312 
1313 		if (fstat(fd_current, &sb) == 0 && S_ISREG(sb.st_mode)) {
1314 			/* if any part of flash_open_tempfile() fails we fall
1315 			 * back to in-place writes
1316 			 */
1317 			fd_target = flash_open_tempfile(&dname, &target_temp);
1318 		}
1319 		dev_target = dev_current;
1320 		if (fd_target == -1)
1321 			fd_target = fd_current;
1322 	}
1323 
1324 	rc = flash_write(fd_current, fd_target, dev_target);
1325 
1326 	if (fsync(fd_current) && !(errno == EINVAL || errno == EROFS)) {
1327 		fprintf(stderr,
1328 			"fsync failed on %s: %s\n",
1329 			DEVNAME(dev_current), strerror(errno));
1330 	}
1331 
1332 	if (fd_current != fd_target) {
1333 		if (fsync(fd_target) &&
1334 		    !(errno == EINVAL || errno == EROFS)) {
1335 			fprintf(stderr,
1336 				"fsync failed on %s: %s\n",
1337 				DEVNAME(dev_current), strerror(errno));
1338 		}
1339 
1340 		if (close(fd_target)) {
1341 			fprintf(stderr,
1342 				"I/O error on %s: %s\n",
1343 				DEVNAME(dev_target), strerror(errno));
1344 			rc = -1;
1345 		}
1346 
1347 		if (rc >= 0 && target_temp) {
1348 			int dir_fd;
1349 
1350 			dir_fd = open(dname, O_DIRECTORY | O_RDONLY);
1351 			if (dir_fd == -1)
1352 				fprintf(stderr,
1353 					"Can't open %s: %s\n",
1354 					dname, strerror(errno));
1355 
1356 			if (rename(target_temp, DEVNAME(dev_target))) {
1357 				fprintf(stderr,
1358 					"rename failed %s => %s: %s\n",
1359 					target_temp, DEVNAME(dev_target),
1360 					strerror(errno));
1361 				rc = -1;
1362 			}
1363 
1364 			if (dir_fd != -1 && fsync(dir_fd))
1365 				fprintf(stderr,
1366 					"fsync failed on %s: %s\n",
1367 					dname, strerror(errno));
1368 
1369 			if (dir_fd != -1 && close(dir_fd))
1370 				fprintf(stderr,
1371 					"I/O error on %s: %s\n",
1372 					dname, strerror(errno));
1373 		}
1374 	}
1375  exit:
1376 	return rc;
1377 }
1378 
flash_io(int mode)1379 static int flash_io(int mode)
1380 {
1381 	int fd_current, rc;
1382 
1383 	/* dev_current: fd_current, erase_current */
1384 	fd_current = open(DEVNAME(dev_current), mode);
1385 	if (fd_current < 0) {
1386 		fprintf(stderr,
1387 			"Can't open %s: %s\n",
1388 			DEVNAME(dev_current), strerror(errno));
1389 		return -1;
1390 	}
1391 
1392 	if (mode == O_RDWR) {
1393 		rc = flash_io_write(fd_current);
1394 	} else {
1395 		rc = flash_read(fd_current);
1396 	}
1397 
1398 	if (close(fd_current)) {
1399 		fprintf(stderr,
1400 			"I/O error on %s: %s\n",
1401 			DEVNAME(dev_current), strerror(errno));
1402 		return -1;
1403 	}
1404 
1405 	return rc;
1406 }
1407 
1408 /*
1409  * Prevent confusion if running from erased flash memory
1410  */
fw_env_open(struct env_opts * opts)1411 int fw_env_open(struct env_opts *opts)
1412 {
1413 	int crc0, crc0_ok;
1414 	unsigned char flag0;
1415 	void *addr0 = NULL;
1416 
1417 	int crc1, crc1_ok;
1418 	unsigned char flag1;
1419 	void *addr1 = NULL;
1420 
1421 	int ret;
1422 
1423 	struct env_image_single *single;
1424 	struct env_image_redundant *redundant;
1425 
1426 	if (!opts)
1427 		opts = &default_opts;
1428 
1429 	if (parse_config(opts))	/* should fill envdevices */
1430 		return -EINVAL;
1431 
1432 	addr0 = calloc(1, CUR_ENVSIZE);
1433 	if (addr0 == NULL) {
1434 		fprintf(stderr,
1435 			"Not enough memory for environment (%ld bytes)\n",
1436 			CUR_ENVSIZE);
1437 		ret = -ENOMEM;
1438 		goto open_cleanup;
1439 	}
1440 
1441 	/* read environment from FLASH to local buffer */
1442 	environment.image = addr0;
1443 
1444 	if (have_redund_env) {
1445 		redundant = addr0;
1446 		environment.crc = &redundant->crc;
1447 		environment.flags = &redundant->flags;
1448 		environment.data = redundant->data;
1449 	} else {
1450 		single = addr0;
1451 		environment.crc = &single->crc;
1452 		environment.flags = NULL;
1453 		environment.data = single->data;
1454 	}
1455 
1456 	dev_current = 0;
1457 	if (flash_io(O_RDONLY)) {
1458 		ret = -EIO;
1459 		goto open_cleanup;
1460 	}
1461 
1462 	crc0 = crc32(0, (uint8_t *)environment.data, ENV_SIZE);
1463 
1464 	crc0_ok = (crc0 == *environment.crc);
1465 	if (!have_redund_env) {
1466 		if (!crc0_ok) {
1467 			fprintf(stderr,
1468 				"Warning: Bad CRC, using default environment\n");
1469 			memcpy(environment.data, default_environment,
1470 			       sizeof(default_environment));
1471 			environment.dirty = 1;
1472 		}
1473 	} else {
1474 		flag0 = *environment.flags;
1475 
1476 		dev_current = 1;
1477 		addr1 = calloc(1, CUR_ENVSIZE);
1478 		if (addr1 == NULL) {
1479 			fprintf(stderr,
1480 				"Not enough memory for environment (%ld bytes)\n",
1481 				CUR_ENVSIZE);
1482 			ret = -ENOMEM;
1483 			goto open_cleanup;
1484 		}
1485 		redundant = addr1;
1486 
1487 		/*
1488 		 * have to set environment.image for flash_read(), careful -
1489 		 * other pointers in environment still point inside addr0
1490 		 */
1491 		environment.image = addr1;
1492 		if (flash_io(O_RDONLY)) {
1493 			ret = -EIO;
1494 			goto open_cleanup;
1495 		}
1496 
1497 		/* Check flag scheme compatibility */
1498 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1499 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1500 			environment.flag_scheme = FLAG_BOOLEAN;
1501 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1502 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1503 			environment.flag_scheme = FLAG_INCREMENTAL;
1504 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1505 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1506 			environment.flag_scheme = FLAG_BOOLEAN;
1507 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1508 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1509 			environment.flag_scheme = FLAG_INCREMENTAL;
1510 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1511 			   DEVTYPE(!dev_current) == MTD_ABSENT &&
1512 			   IS_UBI(dev_current) == IS_UBI(!dev_current)) {
1513 			environment.flag_scheme = FLAG_INCREMENTAL;
1514 		} else {
1515 			fprintf(stderr, "Incompatible flash types!\n");
1516 			ret = -EINVAL;
1517 			goto open_cleanup;
1518 		}
1519 
1520 		crc1 = crc32(0, (uint8_t *)redundant->data, ENV_SIZE);
1521 
1522 		crc1_ok = (crc1 == redundant->crc);
1523 		flag1 = redundant->flags;
1524 
1525 		/*
1526 		 * environment.data still points to ((struct
1527 		 * env_image_redundant *)addr0)->data. If the two
1528 		 * environments differ, or one has bad crc, force a
1529 		 * write-out by marking the environment dirty.
1530 		 */
1531 		if (memcmp(environment.data, redundant->data, ENV_SIZE) ||
1532 		    !crc0_ok || !crc1_ok)
1533 			environment.dirty = 1;
1534 
1535 		if (crc0_ok && !crc1_ok) {
1536 			dev_current = 0;
1537 		} else if (!crc0_ok && crc1_ok) {
1538 			dev_current = 1;
1539 		} else if (!crc0_ok && !crc1_ok) {
1540 			fprintf(stderr,
1541 				"Warning: Bad CRC, using default environment\n");
1542 			memcpy(environment.data, default_environment,
1543 			       sizeof(default_environment));
1544 			environment.dirty = 1;
1545 			dev_current = 0;
1546 		} else {
1547 			switch (environment.flag_scheme) {
1548 			case FLAG_BOOLEAN:
1549 				if (flag0 == ENV_REDUND_ACTIVE &&
1550 				    flag1 == ENV_REDUND_OBSOLETE) {
1551 					dev_current = 0;
1552 				} else if (flag0 == ENV_REDUND_OBSOLETE &&
1553 					   flag1 == ENV_REDUND_ACTIVE) {
1554 					dev_current = 1;
1555 				} else if (flag0 == flag1) {
1556 					dev_current = 0;
1557 				} else if (flag0 == 0xFF) {
1558 					dev_current = 0;
1559 				} else if (flag1 == 0xFF) {
1560 					dev_current = 1;
1561 				} else {
1562 					dev_current = 0;
1563 				}
1564 				break;
1565 			case FLAG_INCREMENTAL:
1566 				if (flag0 == 255 && flag1 == 0)
1567 					dev_current = 1;
1568 				else if ((flag1 == 255 && flag0 == 0) ||
1569 					 flag0 >= flag1)
1570 					dev_current = 0;
1571 				else	/* flag1 > flag0 */
1572 					dev_current = 1;
1573 				break;
1574 			default:
1575 				fprintf(stderr, "Unknown flag scheme %u\n",
1576 					environment.flag_scheme);
1577 				return -1;
1578 			}
1579 		}
1580 
1581 		/*
1582 		 * If we are reading, we don't need the flag and the CRC any
1583 		 * more, if we are writing, we will re-calculate CRC and update
1584 		 * flags before writing out
1585 		 */
1586 		if (dev_current) {
1587 			environment.image = addr1;
1588 			environment.crc = &redundant->crc;
1589 			environment.flags = &redundant->flags;
1590 			environment.data = redundant->data;
1591 			free(addr0);
1592 		} else {
1593 			environment.image = addr0;
1594 			/* Other pointers are already set */
1595 			free(addr1);
1596 		}
1597 #ifdef DEBUG
1598 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1599 #endif
1600 	}
1601 	return 0;
1602 
1603  open_cleanup:
1604 	if (addr0)
1605 		free(addr0);
1606 
1607 	if (addr1)
1608 		free(addr1);
1609 
1610 	return ret;
1611 }
1612 
1613 /*
1614  * Simply free allocated buffer with environment
1615  */
fw_env_close(struct env_opts * opts)1616 int fw_env_close(struct env_opts *opts)
1617 {
1618 	if (environment.image)
1619 		free(environment.image);
1620 
1621 	environment.image = NULL;
1622 
1623 	return 0;
1624 }
1625 
check_device_config(int dev)1626 static int check_device_config(int dev)
1627 {
1628 	struct stat st;
1629 	int32_t lnum = 0;
1630 	int fd, rc = 0;
1631 
1632 	/* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
1633 	ubi_check_dev(dev);
1634 
1635 	fd = open(DEVNAME(dev), O_RDONLY);
1636 	if (fd < 0) {
1637 		fprintf(stderr,
1638 			"Cannot open %s: %s\n", DEVNAME(dev), strerror(errno));
1639 		return -1;
1640 	}
1641 
1642 	rc = fstat(fd, &st);
1643 	if (rc < 0) {
1644 		fprintf(stderr, "Cannot stat the file %s\n", DEVNAME(dev));
1645 		goto err;
1646 	}
1647 
1648 	if (IS_UBI(dev)) {
1649 		rc = ioctl(fd, UBI_IOCEBISMAP, &lnum);
1650 		if (rc < 0) {
1651 			fprintf(stderr, "Cannot get UBI information for %s\n",
1652 				DEVNAME(dev));
1653 			goto err;
1654 		}
1655 	} else if (S_ISCHR(st.st_mode)) {
1656 		struct mtd_info_user mtdinfo;
1657 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1658 		if (rc < 0) {
1659 			fprintf(stderr, "Cannot get MTD information for %s\n",
1660 				DEVNAME(dev));
1661 			goto err;
1662 		}
1663 		if (mtdinfo.type != MTD_NORFLASH &&
1664 		    mtdinfo.type != MTD_NANDFLASH &&
1665 		    mtdinfo.type != MTD_DATAFLASH &&
1666 		    mtdinfo.type != MTD_UBIVOLUME) {
1667 			fprintf(stderr, "Unsupported flash type %u on %s\n",
1668 				mtdinfo.type, DEVNAME(dev));
1669 			goto err;
1670 		}
1671 		DEVTYPE(dev) = mtdinfo.type;
1672 		if (DEVESIZE(dev) == 0 && ENVSECTORS(dev) == 0 &&
1673 		    mtdinfo.type == MTD_NORFLASH)
1674 			DEVESIZE(dev) = mtdinfo.erasesize;
1675 		if (DEVESIZE(dev) == 0)
1676 			/* Assume the erase size is the same as the env-size */
1677 			DEVESIZE(dev) = ENVSIZE(dev);
1678 	} else {
1679 		uint64_t size;
1680 		DEVTYPE(dev) = MTD_ABSENT;
1681 		if (DEVESIZE(dev) == 0)
1682 			/* Assume the erase size to be 512 bytes */
1683 			DEVESIZE(dev) = 0x200;
1684 
1685 		/*
1686 		 * Check for negative offsets, treat it as backwards offset
1687 		 * from the end of the block device
1688 		 */
1689 		if (DEVOFFSET(dev) < 0) {
1690 			rc = ioctl(fd, BLKGETSIZE64, &size);
1691 			if (rc < 0) {
1692 				fprintf(stderr,
1693 					"Could not get block device size on %s\n",
1694 					DEVNAME(dev));
1695 				goto err;
1696 			}
1697 
1698 			DEVOFFSET(dev) = DEVOFFSET(dev) + size;
1699 #ifdef DEBUG
1700 			fprintf(stderr,
1701 				"Calculated device offset 0x%llx on %s\n",
1702 				DEVOFFSET(dev), DEVNAME(dev));
1703 #endif
1704 		}
1705 	}
1706 
1707 	if (ENVSECTORS(dev) == 0)
1708 		/* Assume enough sectors to cover the environment */
1709 		ENVSECTORS(dev) = DIV_ROUND_UP(ENVSIZE(dev), DEVESIZE(dev));
1710 
1711 	if (DEVOFFSET(dev) % DEVESIZE(dev) != 0) {
1712 		fprintf(stderr,
1713 			"Environment does not start on (erase) block boundary\n");
1714 		errno = EINVAL;
1715 		return -1;
1716 	}
1717 
1718 	if (ENVSIZE(dev) > ENVSECTORS(dev) * DEVESIZE(dev)) {
1719 		fprintf(stderr,
1720 			"Environment does not fit into available sectors\n");
1721 		errno = EINVAL;
1722 		return -1;
1723 	}
1724 
1725  err:
1726 	close(fd);
1727 	return rc;
1728 }
1729 
parse_config(struct env_opts * opts)1730 static int parse_config(struct env_opts *opts)
1731 {
1732 	int rc;
1733 
1734 	if (!opts)
1735 		opts = &default_opts;
1736 
1737 #if defined(CONFIG_FILE)
1738 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1739 	if (get_config(opts->config_file)) {
1740 		fprintf(stderr, "Cannot parse config file '%s': %m\n",
1741 			opts->config_file);
1742 		return -1;
1743 	}
1744 #else
1745 	DEVNAME(0) = DEVICE1_NAME;
1746 	DEVOFFSET(0) = DEVICE1_OFFSET;
1747 	ENVSIZE(0) = ENV1_SIZE;
1748 
1749 	/* Set defaults for DEVESIZE, ENVSECTORS later once we
1750 	 * know DEVTYPE
1751 	 */
1752 #ifdef DEVICE1_ESIZE
1753 	DEVESIZE(0) = DEVICE1_ESIZE;
1754 #endif
1755 #ifdef DEVICE1_ENVSECTORS
1756 	ENVSECTORS(0) = DEVICE1_ENVSECTORS;
1757 #endif
1758 
1759 #ifdef HAVE_REDUND
1760 	DEVNAME(1) = DEVICE2_NAME;
1761 	DEVOFFSET(1) = DEVICE2_OFFSET;
1762 	ENVSIZE(1) = ENV2_SIZE;
1763 
1764 	/* Set defaults for DEVESIZE, ENVSECTORS later once we
1765 	 * know DEVTYPE
1766 	 */
1767 #ifdef DEVICE2_ESIZE
1768 	DEVESIZE(1) = DEVICE2_ESIZE;
1769 #endif
1770 #ifdef DEVICE2_ENVSECTORS
1771 	ENVSECTORS(1) = DEVICE2_ENVSECTORS;
1772 #endif
1773 	have_redund_env = 1;
1774 #endif
1775 #endif
1776 	rc = check_device_config(0);
1777 	if (rc < 0)
1778 		return rc;
1779 
1780 	if (have_redund_env) {
1781 		rc = check_device_config(1);
1782 		if (rc < 0)
1783 			return rc;
1784 
1785 		if (ENVSIZE(0) != ENVSIZE(1)) {
1786 			fprintf(stderr,
1787 				"Redundant environments have unequal size\n");
1788 			return -1;
1789 		}
1790 	}
1791 
1792 	usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);
1793 	if (have_redund_env)
1794 		usable_envsize -= sizeof(char);
1795 
1796 	return 0;
1797 }
1798 
1799 #if defined(CONFIG_FILE)
get_config(char * fname)1800 static int get_config(char *fname)
1801 {
1802 	FILE *fp;
1803 	int i = 0;
1804 	int rc;
1805 	char *line = NULL;
1806 	size_t linesize = 0;
1807 	char *devname;
1808 
1809 	fp = fopen(fname, "r");
1810 	if (fp == NULL)
1811 		return -1;
1812 
1813 	while (i < 2 && getline(&line, &linesize, fp) != -1) {
1814 		/* Skip comment strings */
1815 		if (line[0] == '#')
1816 			continue;
1817 
1818 		rc = sscanf(line, "%ms %lli %lx %lx %lx",
1819 			    &devname,
1820 			    &DEVOFFSET(i),
1821 			    &ENVSIZE(i), &DEVESIZE(i), &ENVSECTORS(i));
1822 
1823 		if (rc < 3)
1824 			continue;
1825 
1826 		DEVNAME(i) = devname;
1827 
1828 		/* Set defaults for DEVESIZE, ENVSECTORS later once we
1829 		 * know DEVTYPE
1830 		 */
1831 
1832 		i++;
1833 	}
1834 	free(line);
1835 	fclose(fp);
1836 
1837 	have_redund_env = i - 1;
1838 	if (!i) {		/* No valid entries found */
1839 		errno = EINVAL;
1840 		return -1;
1841 	} else
1842 		return 0;
1843 }
1844 #endif
1845