xref: /openbmc/u-boot/tools/env/fw_env.c (revision 168de20f3b6ccefef0ff5757fa5310f47a95c2f0)
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 <errno.h>
14  #include <env_flags.h>
15  #include <fcntl.h>
16  #include <libgen.h>
17  #include <linux/fs.h>
18  #include <linux/stringify.h>
19  #include <ctype.h>
20  #include <stdio.h>
21  #include <stdlib.h>
22  #include <stddef.h>
23  #include <string.h>
24  #include <sys/types.h>
25  #include <sys/ioctl.h>
26  #include <sys/stat.h>
27  #include <unistd.h>
28  #include <dirent.h>
29  
30  #ifdef MTD_OLD
31  # include <stdint.h>
32  # include <linux/mtd/mtd.h>
33  #else
34  # define  __user	/* nothing */
35  # include <mtd/mtd-user.h>
36  #endif
37  
38  #include <mtd/ubi-user.h>
39  
40  #include "fw_env_private.h"
41  #include "fw_env.h"
42  
43  struct env_opts default_opts = {
44  #ifdef CONFIG_FILE
45  	.config_file = CONFIG_FILE
46  #endif
47  };
48  
49  #define DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
50  
51  #define min(x, y) ({				\
52  	typeof(x) _min1 = (x);			\
53  	typeof(y) _min2 = (y);			\
54  	(void) (&_min1 == &_min2);		\
55  	_min1 < _min2 ? _min1 : _min2; })
56  
57  struct envdev_s {
58  	const char *devname;		/* Device name */
59  	long long devoff;		/* Device offset */
60  	ulong env_size;			/* environment size */
61  	ulong erase_size;		/* device erase size */
62  	ulong env_sectors;		/* number of environment sectors */
63  	uint8_t mtd_type;		/* type of the MTD device */
64  	int is_ubi;			/* set if we use UBI volume */
65  };
66  
67  static struct envdev_s envdevices[2] = {
68  	{
69  		.mtd_type = MTD_ABSENT,
70  	}, {
71  		.mtd_type = MTD_ABSENT,
72  	},
73  };
74  
75  static int dev_current;
76  
77  #define DEVNAME(i)    envdevices[(i)].devname
78  #define DEVOFFSET(i)  envdevices[(i)].devoff
79  #define ENVSIZE(i)    envdevices[(i)].env_size
80  #define DEVESIZE(i)   envdevices[(i)].erase_size
81  #define ENVSECTORS(i) envdevices[(i)].env_sectors
82  #define DEVTYPE(i)    envdevices[(i)].mtd_type
83  #define IS_UBI(i)     envdevices[(i)].is_ubi
84  
85  #define CUR_ENVSIZE ENVSIZE(dev_current)
86  
87  static unsigned long usable_envsize;
88  #define ENV_SIZE      usable_envsize
89  
90  struct env_image_single {
91  	uint32_t crc;		/* CRC32 over data bytes    */
92  	char data[];
93  };
94  
95  struct env_image_redundant {
96  	uint32_t crc;		/* CRC32 over data bytes    */
97  	unsigned char flags;	/* active or obsolete */
98  	char data[];
99  };
100  
101  enum flag_scheme {
102  	FLAG_NONE,
103  	FLAG_BOOLEAN,
104  	FLAG_INCREMENTAL,
105  };
106  
107  struct environment {
108  	void *image;
109  	uint32_t *crc;
110  	unsigned char *flags;
111  	char *data;
112  	enum flag_scheme flag_scheme;
113  };
114  
115  static struct environment environment = {
116  	.flag_scheme = FLAG_NONE,
117  };
118  
119  static int have_redund_env;
120  
121  static unsigned char active_flag = 1;
122  /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
123  static unsigned char obsolete_flag = 0;
124  
125  #define DEFAULT_ENV_INSTANCE_STATIC
126  #include <env_default.h>
127  
128  #define UBI_DEV_START "/dev/ubi"
129  #define UBI_SYSFS "/sys/class/ubi"
130  #define UBI_VOL_NAME_PATT "ubi%d_%d"
131  
is_ubi_devname(const char * devname)132  static int is_ubi_devname(const char *devname)
133  {
134  	return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
135  }
136  
ubi_check_volume_sysfs_name(const char * volume_sysfs_name,const char * volname)137  static int ubi_check_volume_sysfs_name(const char *volume_sysfs_name,
138  				       const char *volname)
139  {
140  	char path[256];
141  	FILE *file;
142  	char *name;
143  	int ret;
144  
145  	strcpy(path, UBI_SYSFS "/");
146  	strcat(path, volume_sysfs_name);
147  	strcat(path, "/name");
148  
149  	file = fopen(path, "r");
150  	if (!file)
151  		return -1;
152  
153  	ret = fscanf(file, "%ms", &name);
154  	fclose(file);
155  	if (ret <= 0 || !name) {
156  		fprintf(stderr,
157  			"Failed to read from file %s, ret = %d, name = %s\n",
158  			path, ret, name);
159  		return -1;
160  	}
161  
162  	if (!strcmp(name, volname)) {
163  		free(name);
164  		return 0;
165  	}
166  	free(name);
167  
168  	return -1;
169  }
170  
ubi_get_volnum_by_name(int devnum,const char * volname)171  static int ubi_get_volnum_by_name(int devnum, const char *volname)
172  {
173  	DIR *sysfs_ubi;
174  	struct dirent *dirent;
175  	int ret;
176  	int tmp_devnum;
177  	int volnum;
178  
179  	sysfs_ubi = opendir(UBI_SYSFS);
180  	if (!sysfs_ubi)
181  		return -1;
182  
183  #ifdef DEBUG
184  	fprintf(stderr, "Looking for volume name \"%s\"\n", volname);
185  #endif
186  
187  	while (1) {
188  		dirent = readdir(sysfs_ubi);
189  		if (!dirent)
190  			return -1;
191  
192  		ret = sscanf(dirent->d_name, UBI_VOL_NAME_PATT,
193  			     &tmp_devnum, &volnum);
194  		if (ret == 2 && devnum == tmp_devnum) {
195  			if (ubi_check_volume_sysfs_name(dirent->d_name,
196  							volname) == 0)
197  				return volnum;
198  		}
199  	}
200  
201  	return -1;
202  }
203  
ubi_get_devnum_by_devname(const char * devname)204  static int ubi_get_devnum_by_devname(const char *devname)
205  {
206  	int devnum;
207  	int ret;
208  
209  	ret = sscanf(devname + sizeof(UBI_DEV_START) - 1, "%d", &devnum);
210  	if (ret != 1)
211  		return -1;
212  
213  	return devnum;
214  }
215  
ubi_get_volume_devname(const char * devname,const char * volname)216  static const char *ubi_get_volume_devname(const char *devname,
217  					  const char *volname)
218  {
219  	char *volume_devname;
220  	int volnum;
221  	int devnum;
222  	int ret;
223  
224  	devnum = ubi_get_devnum_by_devname(devname);
225  	if (devnum < 0)
226  		return NULL;
227  
228  	volnum = ubi_get_volnum_by_name(devnum, volname);
229  	if (volnum < 0)
230  		return NULL;
231  
232  	ret = asprintf(&volume_devname, "%s_%d", devname, volnum);
233  	if (ret < 0)
234  		return NULL;
235  
236  #ifdef DEBUG
237  	fprintf(stderr, "Found ubi volume \"%s:%s\" -> %s\n",
238  		devname, volname, volume_devname);
239  #endif
240  
241  	return volume_devname;
242  }
243  
ubi_check_dev(unsigned int dev_id)244  static void ubi_check_dev(unsigned int dev_id)
245  {
246  	char *devname = (char *)DEVNAME(dev_id);
247  	char *pname;
248  	const char *volname = NULL;
249  	const char *volume_devname;
250  
251  	if (!is_ubi_devname(DEVNAME(dev_id)))
252  		return;
253  
254  	IS_UBI(dev_id) = 1;
255  
256  	for (pname = devname; *pname != '\0'; pname++) {
257  		if (*pname == ':') {
258  			*pname = '\0';
259  			volname = pname + 1;
260  			break;
261  		}
262  	}
263  
264  	if (volname) {
265  		/* Let's find real volume device name */
266  		volume_devname = ubi_get_volume_devname(devname, volname);
267  		if (!volume_devname) {
268  			fprintf(stderr, "Didn't found ubi volume \"%s\"\n",
269  				volname);
270  			return;
271  		}
272  
273  		free(devname);
274  		DEVNAME(dev_id) = volume_devname;
275  	}
276  }
277  
ubi_update_start(int fd,int64_t bytes)278  static int ubi_update_start(int fd, int64_t bytes)
279  {
280  	if (ioctl(fd, UBI_IOCVOLUP, &bytes))
281  		return -1;
282  	return 0;
283  }
284  
ubi_read(int fd,void * buf,size_t count)285  static int ubi_read(int fd, void *buf, size_t count)
286  {
287  	ssize_t ret;
288  
289  	while (count > 0) {
290  		ret = read(fd, buf, count);
291  		if (ret > 0) {
292  			count -= ret;
293  			buf += ret;
294  
295  			continue;
296  		}
297  
298  		if (ret == 0) {
299  			/*
300  			 * Happens in case of too short volume data size. If we
301  			 * return error status we will fail it will be treated
302  			 * as UBI device error.
303  			 *
304  			 * Leave catching this error to CRC check.
305  			 */
306  			fprintf(stderr, "Warning: end of data on ubi volume\n");
307  			return 0;
308  		} else if (errno == EBADF) {
309  			/*
310  			 * Happens in case of corrupted volume. The same as
311  			 * above, we cannot return error now, as we will still
312  			 * be able to successfully write environment later.
313  			 */
314  			fprintf(stderr, "Warning: corrupted volume?\n");
315  			return 0;
316  		} else if (errno == EINTR) {
317  			continue;
318  		}
319  
320  		fprintf(stderr, "Cannot read %u bytes from ubi volume, %s\n",
321  			(unsigned int)count, strerror(errno));
322  		return -1;
323  	}
324  
325  	return 0;
326  }
327  
ubi_write(int fd,const void * buf,size_t count)328  static int ubi_write(int fd, const void *buf, size_t count)
329  {
330  	ssize_t ret;
331  
332  	while (count > 0) {
333  		ret = write(fd, buf, count);
334  		if (ret <= 0) {
335  			if (ret < 0 && errno == EINTR)
336  				continue;
337  
338  			fprintf(stderr, "Cannot write %u bytes to ubi volume\n",
339  				(unsigned int)count);
340  			return -1;
341  		}
342  
343  		count -= ret;
344  		buf += ret;
345  	}
346  
347  	return 0;
348  }
349  
350  static int flash_io(int mode);
351  static int parse_config(struct env_opts *opts);
352  
353  #if defined(CONFIG_FILE)
354  static int get_config(char *);
355  #endif
356  
skip_chars(char * s)357  static char *skip_chars(char *s)
358  {
359  	for (; *s != '\0'; s++) {
360  		if (isblank(*s) || *s == '=')
361  			return s;
362  	}
363  	return NULL;
364  }
365  
skip_blanks(char * s)366  static char *skip_blanks(char *s)
367  {
368  	for (; *s != '\0'; s++) {
369  		if (!isblank(*s))
370  			return s;
371  	}
372  	return NULL;
373  }
374  
375  /*
376   * s1 is either a simple 'name', or a 'name=value' pair.
377   * s2 is a 'name=value' pair.
378   * If the names match, return the value of s2, else NULL.
379   */
envmatch(char * s1,char * s2)380  static char *envmatch(char *s1, char *s2)
381  {
382  	if (s1 == NULL || s2 == NULL)
383  		return NULL;
384  
385  	while (*s1 == *s2++)
386  		if (*s1++ == '=')
387  			return s2;
388  	if (*s1 == '\0' && *(s2 - 1) == '=')
389  		return s2;
390  	return NULL;
391  }
392  
393  /**
394   * Search the environment for a variable.
395   * Return the value, if found, or NULL, if not found.
396   */
fw_getenv(char * name)397  char *fw_getenv(char *name)
398  {
399  	char *env, *nxt;
400  
401  	for (env = environment.data; *env; env = nxt + 1) {
402  		char *val;
403  
404  		for (nxt = env; *nxt; ++nxt) {
405  			if (nxt >= &environment.data[ENV_SIZE]) {
406  				fprintf(stderr, "## Error: "
407  					"environment not terminated\n");
408  				return NULL;
409  			}
410  		}
411  		val = envmatch(name, env);
412  		if (!val)
413  			continue;
414  		return val;
415  	}
416  	return NULL;
417  }
418  
419  /*
420   * Search the default environment for a variable.
421   * Return the value, if found, or NULL, if not found.
422   */
fw_getdefenv(char * name)423  char *fw_getdefenv(char *name)
424  {
425  	char *env, *nxt;
426  
427  	for (env = default_environment; *env; env = nxt + 1) {
428  		char *val;
429  
430  		for (nxt = env; *nxt; ++nxt) {
431  			if (nxt >= &default_environment[ENV_SIZE]) {
432  				fprintf(stderr, "## Error: "
433  					"default environment not terminated\n");
434  				return NULL;
435  			}
436  		}
437  		val = envmatch(name, env);
438  		if (!val)
439  			continue;
440  		return val;
441  	}
442  	return NULL;
443  }
444  
445  /*
446   * Print the current definition of one, or more, or all
447   * environment variables
448   */
fw_printenv(int argc,char * argv[],int value_only,struct env_opts * opts)449  int fw_printenv(int argc, char *argv[], int value_only, struct env_opts *opts)
450  {
451  	int i, rc = 0;
452  
453  	if (value_only && argc != 1) {
454  		fprintf(stderr,
455  			"## Error: `-n'/`--noheader' option requires exactly one argument\n");
456  		return -1;
457  	}
458  
459  	if (!opts)
460  		opts = &default_opts;
461  
462  	if (fw_env_open(opts))
463  		return -1;
464  
465  	if (argc == 0) {	/* Print all env variables  */
466  		char *env, *nxt;
467  		for (env = environment.data; *env; env = nxt + 1) {
468  			for (nxt = env; *nxt; ++nxt) {
469  				if (nxt >= &environment.data[ENV_SIZE]) {
470  					fprintf(stderr, "## Error: "
471  						"environment not terminated\n");
472  					return -1;
473  				}
474  			}
475  
476  			printf("%s\n", env);
477  		}
478  		fw_env_close(opts);
479  		return 0;
480  	}
481  
482  	for (i = 0; i < argc; ++i) {	/* print a subset of env variables */
483  		char *name = argv[i];
484  		char *val = NULL;
485  
486  		val = fw_getenv(name);
487  		if (!val) {
488  			fprintf(stderr, "## Error: \"%s\" not defined\n", name);
489  			rc = -1;
490  			continue;
491  		}
492  
493  		if (value_only) {
494  			puts(val);
495  			break;
496  		}
497  
498  		printf("%s=%s\n", name, val);
499  	}
500  
501  	fw_env_close(opts);
502  
503  	return rc;
504  }
505  
fw_env_flush(struct env_opts * opts)506  int fw_env_flush(struct env_opts *opts)
507  {
508  	if (!opts)
509  		opts = &default_opts;
510  
511  	/*
512  	 * Update CRC
513  	 */
514  	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
515  
516  	/* write environment back to flash */
517  	if (flash_io(O_RDWR)) {
518  		fprintf(stderr, "Error: can't write fw_env to flash\n");
519  		return -1;
520  	}
521  
522  	return 0;
523  }
524  
525  /*
526   * Set/Clear a single variable in the environment.
527   * This is called in sequence to update the environment
528   * in RAM without updating the copy in flash after each set
529   */
fw_env_write(char * name,char * value)530  int fw_env_write(char *name, char *value)
531  {
532  	int len;
533  	char *env, *nxt;
534  	char *oldval = NULL;
535  	int deleting, creating, overwriting;
536  
537  	/*
538  	 * search if variable with this name already exists
539  	 */
540  	for (nxt = env = environment.data; *env; env = nxt + 1) {
541  		for (nxt = env; *nxt; ++nxt) {
542  			if (nxt >= &environment.data[ENV_SIZE]) {
543  				fprintf(stderr, "## Error: "
544  					"environment not terminated\n");
545  				errno = EINVAL;
546  				return -1;
547  			}
548  		}
549  		oldval = envmatch(name, env);
550  		if (oldval)
551  			break;
552  	}
553  
554  	deleting = (oldval && !(value && strlen(value)));
555  	creating = (!oldval && (value && strlen(value)));
556  	overwriting = (oldval && (value && strlen(value)));
557  
558  	/* check for permission */
559  	if (deleting) {
560  		if (env_flags_validate_varaccess(name,
561  		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
562  			printf("Can't delete \"%s\"\n", name);
563  			errno = EROFS;
564  			return -1;
565  		}
566  	} else if (overwriting) {
567  		if (env_flags_validate_varaccess(name,
568  		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
569  			printf("Can't overwrite \"%s\"\n", name);
570  			errno = EROFS;
571  			return -1;
572  		} else if (env_flags_validate_varaccess(name,
573  			   ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
574  			const char *defval = fw_getdefenv(name);
575  
576  			if (defval == NULL)
577  				defval = "";
578  			if (strcmp(oldval, defval)
579  			    != 0) {
580  				printf("Can't overwrite \"%s\"\n", name);
581  				errno = EROFS;
582  				return -1;
583  			}
584  		}
585  	} else if (creating) {
586  		if (env_flags_validate_varaccess(name,
587  		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
588  			printf("Can't create \"%s\"\n", name);
589  			errno = EROFS;
590  			return -1;
591  		}
592  	} else
593  		/* Nothing to do */
594  		return 0;
595  
596  	if (deleting || overwriting) {
597  		if (*++nxt == '\0') {
598  			*env = '\0';
599  		} else {
600  			for (;;) {
601  				*env = *nxt++;
602  				if ((*env == '\0') && (*nxt == '\0'))
603  					break;
604  				++env;
605  			}
606  		}
607  		*++env = '\0';
608  	}
609  
610  	/* Delete only ? */
611  	if (!value || !strlen(value))
612  		return 0;
613  
614  	/*
615  	 * Append new definition at the end
616  	 */
617  	for (env = environment.data; *env || *(env + 1); ++env)
618  		;
619  	if (env > environment.data)
620  		++env;
621  	/*
622  	 * Overflow when:
623  	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
624  	 */
625  	len = strlen(name) + 2;
626  	/* add '=' for first arg, ' ' for all others */
627  	len += strlen(value) + 1;
628  
629  	if (len > (&environment.data[ENV_SIZE] - env)) {
630  		fprintf(stderr,
631  			"Error: environment overflow, \"%s\" deleted\n", name);
632  		return -1;
633  	}
634  
635  	while ((*env = *name++) != '\0')
636  		env++;
637  	*env = '=';
638  	while ((*++env = *value++) != '\0')
639  		;
640  
641  	/* end is marked with double '\0' */
642  	*++env = '\0';
643  
644  	return 0;
645  }
646  
647  /*
648   * Deletes or sets environment variables. Returns -1 and sets errno error codes:
649   * 0	  - OK
650   * EINVAL - need at least 1 argument
651   * EROFS  - certain variables ("ethaddr", "serial#") cannot be
652   *	    modified or deleted
653   *
654   */
fw_env_set(int argc,char * argv[],struct env_opts * opts)655  int fw_env_set(int argc, char *argv[], struct env_opts *opts)
656  {
657  	int i;
658  	size_t len;
659  	char *name, **valv;
660  	char *oldval;
661  	char *value = NULL;
662  	int valc;
663  	int ret;
664  
665  	if (!opts)
666  		opts = &default_opts;
667  
668  	if (argc < 1) {
669  		fprintf(stderr, "## Error: variable name missing\n");
670  		errno = EINVAL;
671  		return -1;
672  	}
673  
674  	if (fw_env_open(opts)) {
675  		fprintf(stderr, "Error: environment not initialized\n");
676  		return -1;
677  	}
678  
679  	name = argv[0];
680  	valv = argv + 1;
681  	valc = argc - 1;
682  
683  	if (env_flags_validate_env_set_params(name, valv, valc) < 0) {
684  		fw_env_close(opts);
685  		return -1;
686  	}
687  
688  	len = 0;
689  	for (i = 0; i < valc; ++i) {
690  		char *val = valv[i];
691  		size_t val_len = strlen(val);
692  
693  		if (value)
694  			value[len - 1] = ' ';
695  		oldval = value;
696  		value = realloc(value, len + val_len + 1);
697  		if (!value) {
698  			fprintf(stderr,
699  				"Cannot malloc %zu bytes: %s\n",
700  				len, strerror(errno));
701  			free(oldval);
702  			return -1;
703  		}
704  
705  		memcpy(value + len, val, val_len);
706  		len += val_len;
707  		value[len++] = '\0';
708  	}
709  
710  	fw_env_write(name, value);
711  
712  	free(value);
713  
714  	ret = fw_env_flush(opts);
715  	fw_env_close(opts);
716  
717  	return ret;
718  }
719  
720  /*
721   * Parse  a file  and configure the u-boot variables.
722   * The script file has a very simple format, as follows:
723   *
724   * Each line has a couple with name, value:
725   * <white spaces>variable_name<white spaces>variable_value
726   *
727   * Both variable_name and variable_value are interpreted as strings.
728   * Any character after <white spaces> and before ending \r\n is interpreted
729   * as variable's value (no comment allowed on these lines !)
730   *
731   * Comments are allowed if the first character in the line is #
732   *
733   * Returns -1 and sets errno error codes:
734   * 0	  - OK
735   * -1     - Error
736   */
fw_parse_script(char * fname,struct env_opts * opts)737  int fw_parse_script(char *fname, struct env_opts *opts)
738  {
739  	FILE *fp;
740  	char *line = NULL;
741  	size_t linesize = 0;
742  	char *name;
743  	char *val;
744  	int lineno = 0;
745  	int len;
746  	int ret = 0;
747  
748  	if (!opts)
749  		opts = &default_opts;
750  
751  	if (fw_env_open(opts)) {
752  		fprintf(stderr, "Error: environment not initialized\n");
753  		return -1;
754  	}
755  
756  	if (strcmp(fname, "-") == 0)
757  		fp = stdin;
758  	else {
759  		fp = fopen(fname, "r");
760  		if (fp == NULL) {
761  			fprintf(stderr, "I cannot open %s for reading\n",
762  				fname);
763  			return -1;
764  		}
765  	}
766  
767  	while ((len = getline(&line, &linesize, fp)) != -1) {
768  		lineno++;
769  
770  		/*
771  		 * Read a whole line from the file. If the line is not
772  		 * terminated, reports an error and exit.
773  		 */
774  		if (line[len - 1] != '\n') {
775  			fprintf(stderr,
776  				"Line %d not correctly terminated\n",
777  				lineno);
778  			ret = -1;
779  			break;
780  		}
781  
782  		/* Drop ending line feed / carriage return */
783  		line[--len] = '\0';
784  		if (len && line[len - 1] == '\r')
785  			line[--len] = '\0';
786  
787  		/* Skip comment or empty lines */
788  		if (len == 0 || line[0] == '#')
789  			continue;
790  
791  		/*
792  		 * Search for variable's name remove leading whitespaces
793  		 */
794  		name = skip_blanks(line);
795  		if (!name)
796  			continue;
797  
798  		/* The first white space is the end of variable name */
799  		val = skip_chars(name);
800  		len = strlen(name);
801  		if (val) {
802  			*val++ = '\0';
803  			if ((val - name) < len)
804  				val = skip_blanks(val);
805  			else
806  				val = NULL;
807  		}
808  #ifdef DEBUG
809  		fprintf(stderr, "Setting %s : %s\n",
810  			name, val ? val : " removed");
811  #endif
812  
813  		if (env_flags_validate_type(name, val) < 0) {
814  			ret = -1;
815  			break;
816  		}
817  
818  		/*
819  		 * If there is an error setting a variable,
820  		 * try to save the environment and returns an error
821  		 */
822  		if (fw_env_write(name, val)) {
823  			fprintf(stderr,
824  				"fw_env_write returns with error : %s\n",
825  				strerror(errno));
826  			ret = -1;
827  			break;
828  		}
829  
830  	}
831  	free(line);
832  
833  	/* Close file if not stdin */
834  	if (strcmp(fname, "-") != 0)
835  		fclose(fp);
836  
837  	ret |= fw_env_flush(opts);
838  
839  	fw_env_close(opts);
840  
841  	return ret;
842  }
843  
844  /**
845   * environment_end() - compute offset of first byte right after environment
846   * @dev - index of enviroment buffer
847   * Return:
848   *  device offset of first byte right after environment
849   */
environment_end(int dev)850  off_t environment_end(int dev)
851  {
852  	/* environment is block aligned */
853  	return DEVOFFSET(dev) + ENVSECTORS(dev) * DEVESIZE(dev);
854  }
855  
856  /*
857   * Test for bad block on NAND, just returns 0 on NOR, on NAND:
858   * 0	- block is good
859   * > 0	- block is bad
860   * < 0	- failed to test
861   */
flash_bad_block(int fd,uint8_t mtd_type,loff_t blockstart)862  static int flash_bad_block(int fd, uint8_t mtd_type, loff_t blockstart)
863  {
864  	if (mtd_type == MTD_NANDFLASH) {
865  		int badblock = ioctl(fd, MEMGETBADBLOCK, &blockstart);
866  
867  		if (badblock < 0) {
868  			perror("Cannot read bad block mark");
869  			return badblock;
870  		}
871  
872  		if (badblock) {
873  #ifdef DEBUG
874  			fprintf(stderr, "Bad block at 0x%llx, skipping\n",
875  				(unsigned long long)blockstart);
876  #endif
877  			return badblock;
878  		}
879  	}
880  
881  	return 0;
882  }
883  
884  /*
885   * Read data from flash at an offset into a provided buffer. On NAND it skips
886   * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
887   * the DEVOFFSET (dev) block. On NOR the loop is only run once.
888   */
flash_read_buf(int dev,int fd,void * buf,size_t count,off_t offset)889  static int flash_read_buf(int dev, int fd, void *buf, size_t count,
890  			  off_t offset)
891  {
892  	size_t blocklen;	/* erase / write length - one block on NAND,
893  				   0 on NOR */
894  	size_t processed = 0;	/* progress counter */
895  	size_t readlen = count;	/* current read length */
896  	off_t block_seek;	/* offset inside the current block to the start
897  				   of the data */
898  	loff_t blockstart;	/* running start of the current block -
899  				   MEMGETBADBLOCK needs 64 bits */
900  	int rc;
901  
902  	blockstart = (offset / DEVESIZE(dev)) * DEVESIZE(dev);
903  
904  	/* Offset inside a block */
905  	block_seek = offset - blockstart;
906  
907  	if (DEVTYPE(dev) == MTD_NANDFLASH) {
908  		/*
909  		 * NAND: calculate which blocks we are reading. We have
910  		 * to read one block at a time to skip bad blocks.
911  		 */
912  		blocklen = DEVESIZE(dev);
913  
914  		/* Limit to one block for the first read */
915  		if (readlen > blocklen - block_seek)
916  			readlen = blocklen - block_seek;
917  	} else {
918  		blocklen = 0;
919  	}
920  
921  	/* This only runs once on NOR flash */
922  	while (processed < count) {
923  		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
924  		if (rc < 0)	/* block test failed */
925  			return -1;
926  
927  		if (blockstart + block_seek + readlen > environment_end(dev)) {
928  			/* End of range is reached */
929  			fprintf(stderr, "Too few good blocks within range\n");
930  			return -1;
931  		}
932  
933  		if (rc) {	/* block is bad */
934  			blockstart += blocklen;
935  			continue;
936  		}
937  
938  		/*
939  		 * If a block is bad, we retry in the next block at the same
940  		 * offset - see env/nand.c::writeenv()
941  		 */
942  		lseek(fd, blockstart + block_seek, SEEK_SET);
943  
944  		rc = read(fd, buf + processed, readlen);
945  		if (rc != readlen) {
946  			fprintf(stderr, "Read error on %s: %s\n",
947  				DEVNAME(dev), strerror(errno));
948  			return -1;
949  		}
950  #ifdef DEBUG
951  		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
952  			rc, (unsigned long long)blockstart + block_seek,
953  			DEVNAME(dev));
954  #endif
955  		processed += readlen;
956  		readlen = min(blocklen, count - processed);
957  		block_seek = 0;
958  		blockstart += blocklen;
959  	}
960  
961  	return processed;
962  }
963  
964  /*
965   * Write count bytes from begin of environment, but stay within
966   * ENVSECTORS(dev) sectors of
967   * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
968   * erase and write the whole data at once.
969   */
flash_write_buf(int dev,int fd,void * buf,size_t count)970  static int flash_write_buf(int dev, int fd, void *buf, size_t count)
971  {
972  	void *data;
973  	struct erase_info_user erase;
974  	size_t blocklen;	/* length of NAND block / NOR erase sector */
975  	size_t erase_len;	/* whole area that can be erased - may include
976  				   bad blocks */
977  	size_t erasesize;	/* erase / write length - one block on NAND,
978  				   whole area on NOR */
979  	size_t processed = 0;	/* progress counter */
980  	size_t write_total;	/* total size to actually write - excluding
981  				   bad blocks */
982  	off_t erase_offset;	/* offset to the first erase block (aligned)
983  				   below offset */
984  	off_t block_seek;	/* offset inside the erase block to the start
985  				   of the data */
986  	loff_t blockstart;	/* running start of the current block -
987  				   MEMGETBADBLOCK needs 64 bits */
988  	int rc;
989  
990  	/*
991  	 * For mtd devices only offset and size of the environment do matter
992  	 */
993  	if (DEVTYPE(dev) == MTD_ABSENT) {
994  		blocklen = count;
995  		erase_len = blocklen;
996  		blockstart = DEVOFFSET(dev);
997  		block_seek = 0;
998  		write_total = blocklen;
999  	} else {
1000  		blocklen = DEVESIZE(dev);
1001  
1002  		erase_offset = DEVOFFSET(dev);
1003  
1004  		/* Maximum area we may use */
1005  		erase_len = environment_end(dev) - erase_offset;
1006  
1007  		blockstart = erase_offset;
1008  
1009  		/* Offset inside a block */
1010  		block_seek = DEVOFFSET(dev) - erase_offset;
1011  
1012  		/*
1013  		 * Data size we actually write: from the start of the block
1014  		 * to the start of the data, then count bytes of data, and
1015  		 * to the end of the block
1016  		 */
1017  		write_total = ((block_seek + count + blocklen - 1) /
1018  			       blocklen) * blocklen;
1019  	}
1020  
1021  	/*
1022  	 * Support data anywhere within erase sectors: read out the complete
1023  	 * area to be erased, replace the environment image, write the whole
1024  	 * block back again.
1025  	 */
1026  	if (write_total > count) {
1027  		data = malloc(erase_len);
1028  		if (!data) {
1029  			fprintf(stderr,
1030  				"Cannot malloc %zu bytes: %s\n",
1031  				erase_len, strerror(errno));
1032  			return -1;
1033  		}
1034  
1035  		rc = flash_read_buf(dev, fd, data, write_total, erase_offset);
1036  		if (write_total != rc)
1037  			return -1;
1038  
1039  #ifdef DEBUG
1040  		fprintf(stderr, "Preserving data ");
1041  		if (block_seek != 0)
1042  			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
1043  		if (block_seek + count != write_total) {
1044  			if (block_seek != 0)
1045  				fprintf(stderr, " and ");
1046  			fprintf(stderr, "0x%lx - 0x%lx",
1047  				(unsigned long)block_seek + count,
1048  				(unsigned long)write_total - 1);
1049  		}
1050  		fprintf(stderr, "\n");
1051  #endif
1052  		/* Overwrite the old environment */
1053  		memcpy(data + block_seek, buf, count);
1054  	} else {
1055  		/*
1056  		 * We get here, iff offset is block-aligned and count is a
1057  		 * multiple of blocklen - see write_total calculation above
1058  		 */
1059  		data = buf;
1060  	}
1061  
1062  	if (DEVTYPE(dev) == MTD_NANDFLASH) {
1063  		/*
1064  		 * NAND: calculate which blocks we are writing. We have
1065  		 * to write one block at a time to skip bad blocks.
1066  		 */
1067  		erasesize = blocklen;
1068  	} else {
1069  		erasesize = erase_len;
1070  	}
1071  
1072  	erase.length = erasesize;
1073  
1074  	/* This only runs once on NOR flash and SPI-dataflash */
1075  	while (processed < write_total) {
1076  		rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
1077  		if (rc < 0)	/* block test failed */
1078  			return rc;
1079  
1080  		if (blockstart + erasesize > environment_end(dev)) {
1081  			fprintf(stderr, "End of range reached, aborting\n");
1082  			return -1;
1083  		}
1084  
1085  		if (rc) {	/* block is bad */
1086  			blockstart += blocklen;
1087  			continue;
1088  		}
1089  
1090  		if (DEVTYPE(dev) != MTD_ABSENT) {
1091  			erase.start = blockstart;
1092  			ioctl(fd, MEMUNLOCK, &erase);
1093  			/* These do not need an explicit erase cycle */
1094  			if (DEVTYPE(dev) != MTD_DATAFLASH)
1095  				if (ioctl(fd, MEMERASE, &erase) != 0) {
1096  					fprintf(stderr,
1097  						"MTD erase error on %s: %s\n",
1098  						DEVNAME(dev), strerror(errno));
1099  					return -1;
1100  				}
1101  		}
1102  
1103  		if (lseek(fd, blockstart, SEEK_SET) == -1) {
1104  			fprintf(stderr,
1105  				"Seek error on %s: %s\n",
1106  				DEVNAME(dev), strerror(errno));
1107  			return -1;
1108  		}
1109  #ifdef DEBUG
1110  		fprintf(stderr, "Write 0x%llx bytes at 0x%llx\n",
1111  			(unsigned long long)erasesize,
1112  			(unsigned long long)blockstart);
1113  #endif
1114  		if (write(fd, data + processed, erasesize) != erasesize) {
1115  			fprintf(stderr, "Write error on %s: %s\n",
1116  				DEVNAME(dev), strerror(errno));
1117  			return -1;
1118  		}
1119  
1120  		if (DEVTYPE(dev) != MTD_ABSENT)
1121  			ioctl(fd, MEMLOCK, &erase);
1122  
1123  		processed += erasesize;
1124  		block_seek = 0;
1125  		blockstart += erasesize;
1126  	}
1127  
1128  	if (write_total > count)
1129  		free(data);
1130  
1131  	return processed;
1132  }
1133  
1134  /*
1135   * Set obsolete flag at offset - NOR flash only
1136   */
flash_flag_obsolete(int dev,int fd,off_t offset)1137  static int flash_flag_obsolete(int dev, int fd, off_t offset)
1138  {
1139  	int rc;
1140  	struct erase_info_user erase;
1141  
1142  	erase.start = DEVOFFSET(dev);
1143  	erase.length = DEVESIZE(dev);
1144  	/* This relies on the fact, that obsolete_flag == 0 */
1145  	rc = lseek(fd, offset, SEEK_SET);
1146  	if (rc < 0) {
1147  		fprintf(stderr, "Cannot seek to set the flag on %s\n",
1148  			DEVNAME(dev));
1149  		return rc;
1150  	}
1151  	ioctl(fd, MEMUNLOCK, &erase);
1152  	rc = write(fd, &obsolete_flag, sizeof(obsolete_flag));
1153  	ioctl(fd, MEMLOCK, &erase);
1154  	if (rc < 0)
1155  		perror("Could not set obsolete flag");
1156  
1157  	return rc;
1158  }
1159  
flash_write(int fd_current,int fd_target,int dev_target)1160  static int flash_write(int fd_current, int fd_target, int dev_target)
1161  {
1162  	int rc;
1163  
1164  	switch (environment.flag_scheme) {
1165  	case FLAG_NONE:
1166  		break;
1167  	case FLAG_INCREMENTAL:
1168  		(*environment.flags)++;
1169  		break;
1170  	case FLAG_BOOLEAN:
1171  		*environment.flags = active_flag;
1172  		break;
1173  	default:
1174  		fprintf(stderr, "Unimplemented flash scheme %u\n",
1175  			environment.flag_scheme);
1176  		return -1;
1177  	}
1178  
1179  #ifdef DEBUG
1180  	fprintf(stderr, "Writing new environment at 0x%llx on %s\n",
1181  		DEVOFFSET(dev_target), DEVNAME(dev_target));
1182  #endif
1183  
1184  	if (IS_UBI(dev_target)) {
1185  		if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
1186  			return 0;
1187  		return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
1188  	}
1189  
1190  	rc = flash_write_buf(dev_target, fd_target, environment.image,
1191  			     CUR_ENVSIZE);
1192  	if (rc < 0)
1193  		return rc;
1194  
1195  	if (environment.flag_scheme == FLAG_BOOLEAN) {
1196  		/* Have to set obsolete flag */
1197  		off_t offset = DEVOFFSET(dev_current) +
1198  		    offsetof(struct env_image_redundant, flags);
1199  #ifdef DEBUG
1200  		fprintf(stderr,
1201  			"Setting obsolete flag in environment at 0x%llx on %s\n",
1202  			DEVOFFSET(dev_current), DEVNAME(dev_current));
1203  #endif
1204  		flash_flag_obsolete(dev_current, fd_current, offset);
1205  	}
1206  
1207  	return 0;
1208  }
1209  
flash_read(int fd)1210  static int flash_read(int fd)
1211  {
1212  	int rc;
1213  
1214  	if (IS_UBI(dev_current)) {
1215  		DEVTYPE(dev_current) = MTD_ABSENT;
1216  
1217  		return ubi_read(fd, environment.image, CUR_ENVSIZE);
1218  	}
1219  
1220  	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1221  			    DEVOFFSET(dev_current));
1222  	if (rc != CUR_ENVSIZE)
1223  		return -1;
1224  
1225  	return 0;
1226  }
1227  
flash_open_tempfile(const char ** dname,const char ** target_temp)1228  static int flash_open_tempfile(const char **dname, const char **target_temp)
1229  {
1230  	char *dup_name = strdup(DEVNAME(dev_current));
1231  	char *temp_name = NULL;
1232  	int rc = -1;
1233  
1234  	if (!dup_name)
1235  		return -1;
1236  
1237  	*dname = dirname(dup_name);
1238  	if (!*dname)
1239  		goto err;
1240  
1241  	rc = asprintf(&temp_name, "%s/XXXXXX", *dname);
1242  	if (rc == -1)
1243  		goto err;
1244  
1245  	rc = mkstemp(temp_name);
1246  	if (rc == -1) {
1247  		/* fall back to in place write */
1248  		fprintf(stderr,
1249  			"Can't create %s: %s\n", temp_name, strerror(errno));
1250  		free(temp_name);
1251  	} else {
1252  		*target_temp = temp_name;
1253  		/* deliberately leak dup_name as dname /might/ point into
1254  		 * it and we need it for our caller
1255  		 */
1256  		dup_name = NULL;
1257  	}
1258  
1259  err:
1260  	if (dup_name)
1261  		free(dup_name);
1262  
1263  	return rc;
1264  }
1265  
flash_io_write(int fd_current)1266  static int flash_io_write(int fd_current)
1267  {
1268  	int fd_target = -1, rc, dev_target;
1269  	const char *dname, *target_temp = NULL;
1270  
1271  	if (have_redund_env) {
1272  		/* switch to next partition for writing */
1273  		dev_target = !dev_current;
1274  		/* dev_target: fd_target, erase_target */
1275  		fd_target = open(DEVNAME(dev_target), O_RDWR);
1276  		if (fd_target < 0) {
1277  			fprintf(stderr,
1278  				"Can't open %s: %s\n",
1279  				DEVNAME(dev_target), strerror(errno));
1280  			rc = -1;
1281  			goto exit;
1282  		}
1283  	} else {
1284  		struct stat sb;
1285  
1286  		if (fstat(fd_current, &sb) == 0 && S_ISREG(sb.st_mode)) {
1287  			/* if any part of flash_open_tempfile() fails we fall
1288  			 * back to in-place writes
1289  			 */
1290  			fd_target = flash_open_tempfile(&dname, &target_temp);
1291  		}
1292  		dev_target = dev_current;
1293  		if (fd_target == -1)
1294  			fd_target = fd_current;
1295  	}
1296  
1297  	rc = flash_write(fd_current, fd_target, dev_target);
1298  
1299  	if (fsync(fd_current) && !(errno == EINVAL || errno == EROFS)) {
1300  		fprintf(stderr,
1301  			"fsync failed on %s: %s\n",
1302  			DEVNAME(dev_current), strerror(errno));
1303  	}
1304  
1305  	if (fd_current != fd_target) {
1306  		if (fsync(fd_target) &&
1307  		    !(errno == EINVAL || errno == EROFS)) {
1308  			fprintf(stderr,
1309  				"fsync failed on %s: %s\n",
1310  				DEVNAME(dev_current), strerror(errno));
1311  		}
1312  
1313  		if (close(fd_target)) {
1314  			fprintf(stderr,
1315  				"I/O error on %s: %s\n",
1316  				DEVNAME(dev_target), strerror(errno));
1317  			rc = -1;
1318  		}
1319  
1320  		if (target_temp) {
1321  			int dir_fd;
1322  
1323  			dir_fd = open(dname, O_DIRECTORY | O_RDONLY);
1324  			if (dir_fd == -1)
1325  				fprintf(stderr,
1326  					"Can't open %s: %s\n",
1327  					dname, strerror(errno));
1328  
1329  			if (rename(target_temp, DEVNAME(dev_target))) {
1330  				fprintf(stderr,
1331  					"rename failed %s => %s: %s\n",
1332  					target_temp, DEVNAME(dev_target),
1333  					strerror(errno));
1334  				rc = -1;
1335  			}
1336  
1337  			if (dir_fd != -1 && fsync(dir_fd))
1338  				fprintf(stderr,
1339  					"fsync failed on %s: %s\n",
1340  					dname, strerror(errno));
1341  
1342  			if (dir_fd != -1 && close(dir_fd))
1343  				fprintf(stderr,
1344  					"I/O error on %s: %s\n",
1345  					dname, strerror(errno));
1346  		}
1347  	}
1348   exit:
1349  	return rc;
1350  }
1351  
flash_io(int mode)1352  static int flash_io(int mode)
1353  {
1354  	int fd_current, rc;
1355  
1356  	/* dev_current: fd_current, erase_current */
1357  	fd_current = open(DEVNAME(dev_current), mode);
1358  	if (fd_current < 0) {
1359  		fprintf(stderr,
1360  			"Can't open %s: %s\n",
1361  			DEVNAME(dev_current), strerror(errno));
1362  		return -1;
1363  	}
1364  
1365  	if (mode == O_RDWR) {
1366  		rc = flash_io_write(fd_current);
1367  	} else {
1368  		rc = flash_read(fd_current);
1369  	}
1370  
1371  	if (close(fd_current)) {
1372  		fprintf(stderr,
1373  			"I/O error on %s: %s\n",
1374  			DEVNAME(dev_current), strerror(errno));
1375  		return -1;
1376  	}
1377  
1378  	return rc;
1379  }
1380  
1381  /*
1382   * Prevent confusion if running from erased flash memory
1383   */
fw_env_open(struct env_opts * opts)1384  int fw_env_open(struct env_opts *opts)
1385  {
1386  	int crc0, crc0_ok;
1387  	unsigned char flag0;
1388  	void *addr0 = NULL;
1389  
1390  	int crc1, crc1_ok;
1391  	unsigned char flag1;
1392  	void *addr1 = NULL;
1393  
1394  	int ret;
1395  
1396  	struct env_image_single *single;
1397  	struct env_image_redundant *redundant;
1398  
1399  	if (!opts)
1400  		opts = &default_opts;
1401  
1402  	if (parse_config(opts))	/* should fill envdevices */
1403  		return -EINVAL;
1404  
1405  	addr0 = calloc(1, CUR_ENVSIZE);
1406  	if (addr0 == NULL) {
1407  		fprintf(stderr,
1408  			"Not enough memory for environment (%ld bytes)\n",
1409  			CUR_ENVSIZE);
1410  		ret = -ENOMEM;
1411  		goto open_cleanup;
1412  	}
1413  
1414  	/* read environment from FLASH to local buffer */
1415  	environment.image = addr0;
1416  
1417  	if (have_redund_env) {
1418  		redundant = addr0;
1419  		environment.crc = &redundant->crc;
1420  		environment.flags = &redundant->flags;
1421  		environment.data = redundant->data;
1422  	} else {
1423  		single = addr0;
1424  		environment.crc = &single->crc;
1425  		environment.flags = NULL;
1426  		environment.data = single->data;
1427  	}
1428  
1429  	dev_current = 0;
1430  	if (flash_io(O_RDONLY)) {
1431  		ret = -EIO;
1432  		goto open_cleanup;
1433  	}
1434  
1435  	crc0 = crc32(0, (uint8_t *)environment.data, ENV_SIZE);
1436  
1437  	crc0_ok = (crc0 == *environment.crc);
1438  	if (!have_redund_env) {
1439  		if (!crc0_ok) {
1440  			fprintf(stderr,
1441  				"Warning: Bad CRC, using default environment\n");
1442  			memcpy(environment.data, default_environment,
1443  			       sizeof(default_environment));
1444  		}
1445  	} else {
1446  		flag0 = *environment.flags;
1447  
1448  		dev_current = 1;
1449  		addr1 = calloc(1, CUR_ENVSIZE);
1450  		if (addr1 == NULL) {
1451  			fprintf(stderr,
1452  				"Not enough memory for environment (%ld bytes)\n",
1453  				CUR_ENVSIZE);
1454  			ret = -ENOMEM;
1455  			goto open_cleanup;
1456  		}
1457  		redundant = addr1;
1458  
1459  		/*
1460  		 * have to set environment.image for flash_read(), careful -
1461  		 * other pointers in environment still point inside addr0
1462  		 */
1463  		environment.image = addr1;
1464  		if (flash_io(O_RDONLY)) {
1465  			ret = -EIO;
1466  			goto open_cleanup;
1467  		}
1468  
1469  		/* Check flag scheme compatibility */
1470  		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1471  		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1472  			environment.flag_scheme = FLAG_BOOLEAN;
1473  		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1474  			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1475  			environment.flag_scheme = FLAG_INCREMENTAL;
1476  		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1477  			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1478  			environment.flag_scheme = FLAG_BOOLEAN;
1479  		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1480  			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1481  			environment.flag_scheme = FLAG_INCREMENTAL;
1482  		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1483  			   DEVTYPE(!dev_current) == MTD_ABSENT &&
1484  			   IS_UBI(dev_current) == IS_UBI(!dev_current)) {
1485  			environment.flag_scheme = FLAG_INCREMENTAL;
1486  		} else {
1487  			fprintf(stderr, "Incompatible flash types!\n");
1488  			ret = -EINVAL;
1489  			goto open_cleanup;
1490  		}
1491  
1492  		crc1 = crc32(0, (uint8_t *)redundant->data, ENV_SIZE);
1493  
1494  		crc1_ok = (crc1 == redundant->crc);
1495  		flag1 = redundant->flags;
1496  
1497  		if (crc0_ok && !crc1_ok) {
1498  			dev_current = 0;
1499  		} else if (!crc0_ok && crc1_ok) {
1500  			dev_current = 1;
1501  		} else if (!crc0_ok && !crc1_ok) {
1502  			fprintf(stderr,
1503  				"Warning: Bad CRC, using default environment\n");
1504  			memcpy(environment.data, default_environment,
1505  			       sizeof(default_environment));
1506  			dev_current = 0;
1507  		} else {
1508  			switch (environment.flag_scheme) {
1509  			case FLAG_BOOLEAN:
1510  				if (flag0 == active_flag &&
1511  				    flag1 == obsolete_flag) {
1512  					dev_current = 0;
1513  				} else if (flag0 == obsolete_flag &&
1514  					   flag1 == active_flag) {
1515  					dev_current = 1;
1516  				} else if (flag0 == flag1) {
1517  					dev_current = 0;
1518  				} else if (flag0 == 0xFF) {
1519  					dev_current = 0;
1520  				} else if (flag1 == 0xFF) {
1521  					dev_current = 1;
1522  				} else {
1523  					dev_current = 0;
1524  				}
1525  				break;
1526  			case FLAG_INCREMENTAL:
1527  				if (flag0 == 255 && flag1 == 0)
1528  					dev_current = 1;
1529  				else if ((flag1 == 255 && flag0 == 0) ||
1530  					 flag0 >= flag1)
1531  					dev_current = 0;
1532  				else	/* flag1 > flag0 */
1533  					dev_current = 1;
1534  				break;
1535  			default:
1536  				fprintf(stderr, "Unknown flag scheme %u\n",
1537  					environment.flag_scheme);
1538  				return -1;
1539  			}
1540  		}
1541  
1542  		/*
1543  		 * If we are reading, we don't need the flag and the CRC any
1544  		 * more, if we are writing, we will re-calculate CRC and update
1545  		 * flags before writing out
1546  		 */
1547  		if (dev_current) {
1548  			environment.image = addr1;
1549  			environment.crc = &redundant->crc;
1550  			environment.flags = &redundant->flags;
1551  			environment.data = redundant->data;
1552  			free(addr0);
1553  		} else {
1554  			environment.image = addr0;
1555  			/* Other pointers are already set */
1556  			free(addr1);
1557  		}
1558  #ifdef DEBUG
1559  		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1560  #endif
1561  	}
1562  	return 0;
1563  
1564   open_cleanup:
1565  	if (addr0)
1566  		free(addr0);
1567  
1568  	if (addr1)
1569  		free(addr0);
1570  
1571  	return ret;
1572  }
1573  
1574  /*
1575   * Simply free allocated buffer with environment
1576   */
fw_env_close(struct env_opts * opts)1577  int fw_env_close(struct env_opts *opts)
1578  {
1579  	if (environment.image)
1580  		free(environment.image);
1581  
1582  	environment.image = NULL;
1583  
1584  	return 0;
1585  }
1586  
check_device_config(int dev)1587  static int check_device_config(int dev)
1588  {
1589  	struct stat st;
1590  	int32_t lnum = 0;
1591  	int fd, rc = 0;
1592  
1593  	/* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
1594  	ubi_check_dev(dev);
1595  
1596  	fd = open(DEVNAME(dev), O_RDONLY);
1597  	if (fd < 0) {
1598  		fprintf(stderr,
1599  			"Cannot open %s: %s\n", DEVNAME(dev), strerror(errno));
1600  		return -1;
1601  	}
1602  
1603  	rc = fstat(fd, &st);
1604  	if (rc < 0) {
1605  		fprintf(stderr, "Cannot stat the file %s\n", DEVNAME(dev));
1606  		goto err;
1607  	}
1608  
1609  	if (IS_UBI(dev)) {
1610  		rc = ioctl(fd, UBI_IOCEBISMAP, &lnum);
1611  		if (rc < 0) {
1612  			fprintf(stderr, "Cannot get UBI information for %s\n",
1613  				DEVNAME(dev));
1614  			goto err;
1615  		}
1616  	} else if (S_ISCHR(st.st_mode)) {
1617  		struct mtd_info_user mtdinfo;
1618  		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1619  		if (rc < 0) {
1620  			fprintf(stderr, "Cannot get MTD information for %s\n",
1621  				DEVNAME(dev));
1622  			goto err;
1623  		}
1624  		if (mtdinfo.type != MTD_NORFLASH &&
1625  		    mtdinfo.type != MTD_NANDFLASH &&
1626  		    mtdinfo.type != MTD_DATAFLASH &&
1627  		    mtdinfo.type != MTD_UBIVOLUME) {
1628  			fprintf(stderr, "Unsupported flash type %u on %s\n",
1629  				mtdinfo.type, DEVNAME(dev));
1630  			goto err;
1631  		}
1632  		DEVTYPE(dev) = mtdinfo.type;
1633  		if (DEVESIZE(dev) == 0)
1634  			/* Assume the erase size is the same as the env-size */
1635  			DEVESIZE(dev) = ENVSIZE(dev);
1636  	} else {
1637  		uint64_t size;
1638  		DEVTYPE(dev) = MTD_ABSENT;
1639  		if (DEVESIZE(dev) == 0)
1640  			/* Assume the erase size to be 512 bytes */
1641  			DEVESIZE(dev) = 0x200;
1642  
1643  		/*
1644  		 * Check for negative offsets, treat it as backwards offset
1645  		 * from the end of the block device
1646  		 */
1647  		if (DEVOFFSET(dev) < 0) {
1648  			rc = ioctl(fd, BLKGETSIZE64, &size);
1649  			if (rc < 0) {
1650  				fprintf(stderr,
1651  					"Could not get block device size on %s\n",
1652  					DEVNAME(dev));
1653  				goto err;
1654  			}
1655  
1656  			DEVOFFSET(dev) = DEVOFFSET(dev) + size;
1657  #ifdef DEBUG
1658  			fprintf(stderr,
1659  				"Calculated device offset 0x%llx on %s\n",
1660  				DEVOFFSET(dev), DEVNAME(dev));
1661  #endif
1662  		}
1663  	}
1664  
1665  	if (ENVSECTORS(dev) == 0)
1666  		/* Assume enough sectors to cover the environment */
1667  		ENVSECTORS(dev) = DIV_ROUND_UP(ENVSIZE(dev), DEVESIZE(dev));
1668  
1669  	if (DEVOFFSET(dev) % DEVESIZE(dev) != 0) {
1670  		fprintf(stderr,
1671  			"Environment does not start on (erase) block boundary\n");
1672  		errno = EINVAL;
1673  		return -1;
1674  	}
1675  
1676  	if (ENVSIZE(dev) > ENVSECTORS(dev) * DEVESIZE(dev)) {
1677  		fprintf(stderr,
1678  			"Environment does not fit into available sectors\n");
1679  		errno = EINVAL;
1680  		return -1;
1681  	}
1682  
1683   err:
1684  	close(fd);
1685  	return rc;
1686  }
1687  
parse_config(struct env_opts * opts)1688  static int parse_config(struct env_opts *opts)
1689  {
1690  	int rc;
1691  
1692  	if (!opts)
1693  		opts = &default_opts;
1694  
1695  #if defined(CONFIG_FILE)
1696  	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1697  	if (get_config(opts->config_file)) {
1698  		fprintf(stderr, "Cannot parse config file '%s': %m\n",
1699  			opts->config_file);
1700  		return -1;
1701  	}
1702  #else
1703  	DEVNAME(0) = DEVICE1_NAME;
1704  	DEVOFFSET(0) = DEVICE1_OFFSET;
1705  	ENVSIZE(0) = ENV1_SIZE;
1706  
1707  	/* Set defaults for DEVESIZE, ENVSECTORS later once we
1708  	 * know DEVTYPE
1709  	 */
1710  #ifdef DEVICE1_ESIZE
1711  	DEVESIZE(0) = DEVICE1_ESIZE;
1712  #endif
1713  #ifdef DEVICE1_ENVSECTORS
1714  	ENVSECTORS(0) = DEVICE1_ENVSECTORS;
1715  #endif
1716  
1717  #ifdef HAVE_REDUND
1718  	DEVNAME(1) = DEVICE2_NAME;
1719  	DEVOFFSET(1) = DEVICE2_OFFSET;
1720  	ENVSIZE(1) = ENV2_SIZE;
1721  
1722  	/* Set defaults for DEVESIZE, ENVSECTORS later once we
1723  	 * know DEVTYPE
1724  	 */
1725  #ifdef DEVICE2_ESIZE
1726  	DEVESIZE(1) = DEVICE2_ESIZE;
1727  #endif
1728  #ifdef DEVICE2_ENVSECTORS
1729  	ENVSECTORS(1) = DEVICE2_ENVSECTORS;
1730  #endif
1731  	have_redund_env = 1;
1732  #endif
1733  #endif
1734  	rc = check_device_config(0);
1735  	if (rc < 0)
1736  		return rc;
1737  
1738  	if (have_redund_env) {
1739  		rc = check_device_config(1);
1740  		if (rc < 0)
1741  			return rc;
1742  
1743  		if (ENVSIZE(0) != ENVSIZE(1)) {
1744  			fprintf(stderr,
1745  				"Redundant environments have unequal size");
1746  			return -1;
1747  		}
1748  	}
1749  
1750  	usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);
1751  	if (have_redund_env)
1752  		usable_envsize -= sizeof(char);
1753  
1754  	return 0;
1755  }
1756  
1757  #if defined(CONFIG_FILE)
get_config(char * fname)1758  static int get_config(char *fname)
1759  {
1760  	FILE *fp;
1761  	int i = 0;
1762  	int rc;
1763  	char *line = NULL;
1764  	size_t linesize = 0;
1765  	char *devname;
1766  
1767  	fp = fopen(fname, "r");
1768  	if (fp == NULL)
1769  		return -1;
1770  
1771  	while (i < 2 && getline(&line, &linesize, fp) != -1) {
1772  		/* Skip comment strings */
1773  		if (line[0] == '#')
1774  			continue;
1775  
1776  		rc = sscanf(line, "%ms %lli %lx %lx %lx",
1777  			    &devname,
1778  			    &DEVOFFSET(i),
1779  			    &ENVSIZE(i), &DEVESIZE(i), &ENVSECTORS(i));
1780  
1781  		if (rc < 3)
1782  			continue;
1783  
1784  		DEVNAME(i) = devname;
1785  
1786  		/* Set defaults for DEVESIZE, ENVSECTORS later once we
1787  		 * know DEVTYPE
1788  		 */
1789  
1790  		i++;
1791  	}
1792  	free(line);
1793  	fclose(fp);
1794  
1795  	have_redund_env = i - 1;
1796  	if (!i) {		/* No valid entries found */
1797  		errno = EINVAL;
1798  		return -1;
1799  	} else
1800  		return 0;
1801  }
1802  #endif
1803