xref: /rk3399_rockchip-uboot/tools/env/fw_env.c (revision 8b27abd8ab1f9d04b8eb93a1759ff8dec7c9d576)
1 /*
2  * (C) Copyright 2000-2010
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2008
6  * Guennadi Liakhovetski, DENX Software Engineering, lg@denx.de.
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #define _GNU_SOURCE
12 
13 #include <compiler.h>
14 #include <errno.h>
15 #include <env_flags.h>
16 #include <fcntl.h>
17 #include <linux/stringify.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <stddef.h>
21 #include <string.h>
22 #include <sys/types.h>
23 #include <sys/ioctl.h>
24 #include <sys/stat.h>
25 #include <unistd.h>
26 
27 #ifdef MTD_OLD
28 # include <stdint.h>
29 # include <linux/mtd/mtd.h>
30 #else
31 # define  __user	/* nothing */
32 # include <mtd/mtd-user.h>
33 #endif
34 
35 #include "fw_env.h"
36 
37 #include <aes.h>
38 
39 #define DIV_ROUND_UP(n, d)	(((n) + (d) - 1) / (d))
40 
41 #define WHITESPACE(c) ((c == '\t') || (c == ' '))
42 
43 #define min(x, y) ({				\
44 	typeof(x) _min1 = (x);			\
45 	typeof(y) _min2 = (y);			\
46 	(void) (&_min1 == &_min2);		\
47 	_min1 < _min2 ? _min1 : _min2; })
48 
49 struct envdev_s {
50 	const char *devname;		/* Device name */
51 	ulong devoff;			/* Device offset */
52 	ulong env_size;			/* environment size */
53 	ulong erase_size;		/* device erase size */
54 	ulong env_sectors;		/* number of environment sectors */
55 	uint8_t mtd_type;		/* type of the MTD device */
56 };
57 
58 static struct envdev_s envdevices[2] =
59 {
60 	{
61 		.mtd_type = MTD_ABSENT,
62 	}, {
63 		.mtd_type = MTD_ABSENT,
64 	},
65 };
66 static int dev_current;
67 
68 #define DEVNAME(i)    envdevices[(i)].devname
69 #define DEVOFFSET(i)  envdevices[(i)].devoff
70 #define ENVSIZE(i)    envdevices[(i)].env_size
71 #define DEVESIZE(i)   envdevices[(i)].erase_size
72 #define ENVSECTORS(i) envdevices[(i)].env_sectors
73 #define DEVTYPE(i)    envdevices[(i)].mtd_type
74 
75 #define CUR_ENVSIZE ENVSIZE(dev_current)
76 
77 #define ENV_SIZE      getenvsize()
78 
79 struct env_image_single {
80 	uint32_t	crc;	/* CRC32 over data bytes    */
81 	char		data[];
82 };
83 
84 struct env_image_redundant {
85 	uint32_t	crc;	/* CRC32 over data bytes    */
86 	unsigned char	flags;	/* active or obsolete */
87 	char		data[];
88 };
89 
90 enum flag_scheme {
91 	FLAG_NONE,
92 	FLAG_BOOLEAN,
93 	FLAG_INCREMENTAL,
94 };
95 
96 struct environment {
97 	void			*image;
98 	uint32_t		*crc;
99 	unsigned char		*flags;
100 	char			*data;
101 	enum flag_scheme	flag_scheme;
102 };
103 
104 static struct environment environment = {
105 	.flag_scheme = FLAG_NONE,
106 };
107 
108 /* Is AES encryption used? */
109 static int aes_flag;
110 static uint8_t aes_key[AES_KEY_LENGTH] = { 0 };
111 static int env_aes_cbc_crypt(char *data, const int enc);
112 
113 static int HaveRedundEnv = 0;
114 
115 static unsigned char active_flag = 1;
116 /* obsolete_flag must be 0 to efficiently set it on NOR flash without erasing */
117 static unsigned char obsolete_flag = 0;
118 
119 #define DEFAULT_ENV_INSTANCE_STATIC
120 #include <env_default.h>
121 
122 static int flash_io (int mode);
123 static char *envmatch (char * s1, char * s2);
124 static int parse_config (void);
125 
126 #if defined(CONFIG_FILE)
127 static int get_config (char *);
128 static char *config_file = CONFIG_FILE;
129 #endif
130 static inline ulong getenvsize (void)
131 {
132 	ulong rc = CUR_ENVSIZE - sizeof(uint32_t);
133 
134 	if (HaveRedundEnv)
135 		rc -= sizeof (char);
136 
137 	if (aes_flag)
138 		rc &= ~(AES_KEY_LENGTH - 1);
139 
140 	return rc;
141 }
142 
143 static char *fw_string_blank(char *s, int noblank)
144 {
145 	int i;
146 	int len = strlen(s);
147 
148 	for (i = 0; i < len; i++, s++) {
149 		if ((noblank && !WHITESPACE(*s)) ||
150 			(!noblank && WHITESPACE(*s)))
151 			break;
152 	}
153 	if (i == len)
154 		return NULL;
155 
156 	return s;
157 }
158 
159 /*
160  * Search the environment for a variable.
161  * Return the value, if found, or NULL, if not found.
162  */
163 char *fw_getenv (char *name)
164 {
165 	char *env, *nxt;
166 
167 	for (env = environment.data; *env; env = nxt + 1) {
168 		char *val;
169 
170 		for (nxt = env; *nxt; ++nxt) {
171 			if (nxt >= &environment.data[ENV_SIZE]) {
172 				fprintf (stderr, "## Error: "
173 					"environment not terminated\n");
174 				return NULL;
175 			}
176 		}
177 		val = envmatch (name, env);
178 		if (!val)
179 			continue;
180 		return val;
181 	}
182 	return NULL;
183 }
184 
185 /*
186  * Search the default environment for a variable.
187  * Return the value, if found, or NULL, if not found.
188  */
189 char *fw_getdefenv(char *name)
190 {
191 	char *env, *nxt;
192 
193 	for (env = default_environment; *env; env = nxt + 1) {
194 		char *val;
195 
196 		for (nxt = env; *nxt; ++nxt) {
197 			if (nxt >= &default_environment[ENV_SIZE]) {
198 				fprintf(stderr, "## Error: "
199 					"default environment not terminated\n");
200 				return NULL;
201 			}
202 		}
203 		val = envmatch(name, env);
204 		if (!val)
205 			continue;
206 		return val;
207 	}
208 	return NULL;
209 }
210 
211 static int parse_aes_key(char *key, uint8_t *bin_key)
212 {
213 	char tmp[5] = { '0', 'x', 0, 0, 0 };
214 	unsigned long ul;
215 	int i;
216 
217 	if (strnlen(key, 64) != 32) {
218 		fprintf(stderr,
219 			"## Error: '-a' option requires 16-byte AES key\n");
220 		return -1;
221 	}
222 
223 	for (i = 0; i < 16; i++) {
224 		tmp[2] = key[0];
225 		tmp[3] = key[1];
226 		errno = 0;
227 		ul = strtoul(tmp, NULL, 16);
228 		if (errno) {
229 			fprintf(stderr,
230 				"## Error: '-a' option requires valid AES key\n");
231 			return -1;
232 		}
233 		bin_key[i] = ul & 0xff;
234 		key += 2;
235 	}
236 	return 0;
237 }
238 
239 /*
240  * Print the current definition of one, or more, or all
241  * environment variables
242  */
243 int fw_printenv (int argc, char *argv[])
244 {
245 	char *env, *nxt;
246 	int i, n_flag;
247 	int rc = 0;
248 
249 #ifdef CONFIG_FILE
250 	if (argc >= 2 && strcmp(argv[1], "-c") == 0) {
251 		if (argc < 3) {
252 			fprintf(stderr,
253 				"## Error: '-c' option requires the config file to use\n");
254 			return -1;
255 		}
256 		config_file = argv[2];
257 		argv += 2;
258 		argc -= 2;
259 	}
260 #endif
261 
262 	if (argc >= 2 && strcmp(argv[1], "-a") == 0) {
263 		if (argc < 3) {
264 			fprintf(stderr,
265 				"## Error: '-a' option requires AES key\n");
266 			return -1;
267 		}
268 		rc = parse_aes_key(argv[2], aes_key);
269 		if (rc)
270 			return rc;
271 		aes_flag = 1;
272 		argv += 2;
273 		argc -= 2;
274 	}
275 
276 	if (fw_env_open())
277 		return -1;
278 
279 	if (argc == 1) {		/* Print all env variables  */
280 		for (env = environment.data; *env; env = nxt + 1) {
281 			for (nxt = env; *nxt; ++nxt) {
282 				if (nxt >= &environment.data[ENV_SIZE]) {
283 					fprintf (stderr, "## Error: "
284 						"environment not terminated\n");
285 					return -1;
286 				}
287 			}
288 
289 			printf ("%s\n", env);
290 		}
291 		return 0;
292 	}
293 
294 	if (strcmp (argv[1], "-n") == 0) {
295 		n_flag = 1;
296 		++argv;
297 		--argc;
298 		if (argc != 2) {
299 			fprintf (stderr, "## Error: "
300 				"`-n' option requires exactly one argument\n");
301 			return -1;
302 		}
303 	} else {
304 		n_flag = 0;
305 	}
306 
307 	for (i = 1; i < argc; ++i) {	/* print single env variables   */
308 		char *name = argv[i];
309 		char *val = NULL;
310 
311 		for (env = environment.data; *env; env = nxt + 1) {
312 
313 			for (nxt = env; *nxt; ++nxt) {
314 				if (nxt >= &environment.data[ENV_SIZE]) {
315 					fprintf (stderr, "## Error: "
316 						"environment not terminated\n");
317 					return -1;
318 				}
319 			}
320 			val = envmatch (name, env);
321 			if (val) {
322 				if (!n_flag) {
323 					fputs (name, stdout);
324 					putc ('=', stdout);
325 				}
326 				puts (val);
327 				break;
328 			}
329 		}
330 		if (!val) {
331 			fprintf (stderr, "## Error: \"%s\" not defined\n", name);
332 			rc = -1;
333 		}
334 	}
335 
336 	return rc;
337 }
338 
339 int fw_env_close(void)
340 {
341 	int ret;
342 	if (aes_flag) {
343 		ret = env_aes_cbc_crypt(environment.data, 1);
344 		if (ret) {
345 			fprintf(stderr,
346 				"Error: can't encrypt env for flash\n");
347 			return ret;
348 		}
349 	}
350 
351 	/*
352 	 * Update CRC
353 	 */
354 	*environment.crc = crc32(0, (uint8_t *) environment.data, ENV_SIZE);
355 
356 	/* write environment back to flash */
357 	if (flash_io(O_RDWR)) {
358 		fprintf(stderr,
359 			"Error: can't write fw_env to flash\n");
360 			return -1;
361 	}
362 
363 	return 0;
364 }
365 
366 
367 /*
368  * Set/Clear a single variable in the environment.
369  * This is called in sequence to update the environment
370  * in RAM without updating the copy in flash after each set
371  */
372 int fw_env_write(char *name, char *value)
373 {
374 	int len;
375 	char *env, *nxt;
376 	char *oldval = NULL;
377 	int deleting, creating, overwriting;
378 
379 	/*
380 	 * search if variable with this name already exists
381 	 */
382 	for (nxt = env = environment.data; *env; env = nxt + 1) {
383 		for (nxt = env; *nxt; ++nxt) {
384 			if (nxt >= &environment.data[ENV_SIZE]) {
385 				fprintf(stderr, "## Error: "
386 					"environment not terminated\n");
387 				errno = EINVAL;
388 				return -1;
389 			}
390 		}
391 		if ((oldval = envmatch (name, env)) != NULL)
392 			break;
393 	}
394 
395 	deleting = (oldval && !(value && strlen(value)));
396 	creating = (!oldval && (value && strlen(value)));
397 	overwriting = (oldval && (value && strlen(value)));
398 
399 	/* check for permission */
400 	if (deleting) {
401 		if (env_flags_validate_varaccess(name,
402 		    ENV_FLAGS_VARACCESS_PREVENT_DELETE)) {
403 			printf("Can't delete \"%s\"\n", name);
404 			errno = EROFS;
405 			return -1;
406 		}
407 	} else if (overwriting) {
408 		if (env_flags_validate_varaccess(name,
409 		    ENV_FLAGS_VARACCESS_PREVENT_OVERWR)) {
410 			printf("Can't overwrite \"%s\"\n", name);
411 			errno = EROFS;
412 			return -1;
413 		} else if (env_flags_validate_varaccess(name,
414 		    ENV_FLAGS_VARACCESS_PREVENT_NONDEF_OVERWR)) {
415 			const char *defval = fw_getdefenv(name);
416 
417 			if (defval == NULL)
418 				defval = "";
419 			if (strcmp(oldval, defval)
420 			    != 0) {
421 				printf("Can't overwrite \"%s\"\n", name);
422 				errno = EROFS;
423 				return -1;
424 			}
425 		}
426 	} else if (creating) {
427 		if (env_flags_validate_varaccess(name,
428 		    ENV_FLAGS_VARACCESS_PREVENT_CREATE)) {
429 			printf("Can't create \"%s\"\n", name);
430 			errno = EROFS;
431 			return -1;
432 		}
433 	} else
434 		/* Nothing to do */
435 		return 0;
436 
437 	if (deleting || overwriting) {
438 		if (*++nxt == '\0') {
439 			*env = '\0';
440 		} else {
441 			for (;;) {
442 				*env = *nxt++;
443 				if ((*env == '\0') && (*nxt == '\0'))
444 					break;
445 				++env;
446 			}
447 		}
448 		*++env = '\0';
449 	}
450 
451 	/* Delete only ? */
452 	if (!value || !strlen(value))
453 		return 0;
454 
455 	/*
456 	 * Append new definition at the end
457 	 */
458 	for (env = environment.data; *env || *(env + 1); ++env);
459 	if (env > environment.data)
460 		++env;
461 	/*
462 	 * Overflow when:
463 	 * "name" + "=" + "val" +"\0\0"  > CUR_ENVSIZE - (env-environment)
464 	 */
465 	len = strlen (name) + 2;
466 	/* add '=' for first arg, ' ' for all others */
467 	len += strlen(value) + 1;
468 
469 	if (len > (&environment.data[ENV_SIZE] - env)) {
470 		fprintf (stderr,
471 			"Error: environment overflow, \"%s\" deleted\n",
472 			name);
473 		return -1;
474 	}
475 
476 	while ((*env = *name++) != '\0')
477 		env++;
478 	*env = '=';
479 	while ((*++env = *value++) != '\0')
480 		;
481 
482 	/* end is marked with double '\0' */
483 	*++env = '\0';
484 
485 	return 0;
486 }
487 
488 /*
489  * Deletes or sets environment variables. Returns -1 and sets errno error codes:
490  * 0	  - OK
491  * EINVAL - need at least 1 argument
492  * EROFS  - certain variables ("ethaddr", "serial#") cannot be
493  *	    modified or deleted
494  *
495  */
496 int fw_setenv(int argc, char *argv[])
497 {
498 	int i, rc;
499 	size_t len;
500 	char *name, **valv;
501 	char *value = NULL;
502 	int valc;
503 
504 #ifdef CONFIG_FILE
505 	if (argc >= 2 && strcmp(argv[1], "-c") == 0) {
506 		if (argc < 3) {
507 			fprintf(stderr,
508 				"## Error: '-c' option requires the config file to use\n");
509 			return -1;
510 		}
511 		config_file = argv[2];
512 		argv += 2;
513 		argc -= 2;
514 	}
515 #endif
516 
517 	if (argc < 2) {
518 		errno = EINVAL;
519 		return -1;
520 	}
521 
522 	if (strcmp(argv[1], "-a") == 0) {
523 		if (argc < 3) {
524 			fprintf(stderr,
525 				"## Error: '-a' option requires AES key\n");
526 			return -1;
527 		}
528 		rc = parse_aes_key(argv[2], aes_key);
529 		if (rc)
530 			return rc;
531 		aes_flag = 1;
532 		argv += 2;
533 		argc -= 2;
534 	}
535 
536 	if (argc < 2) {
537 		errno = EINVAL;
538 		return -1;
539 	}
540 
541 	if (fw_env_open()) {
542 		fprintf(stderr, "Error: environment not initialized\n");
543 		return -1;
544 	}
545 
546 	name = argv[1];
547 	valv = argv + 2;
548 	valc = argc - 2;
549 
550 	if (env_flags_validate_env_set_params(name, valv, valc) < 0)
551 		return 1;
552 
553 	len = 0;
554 	for (i = 0; i < valc; ++i) {
555 		char *val = valv[i];
556 		size_t val_len = strlen(val);
557 
558 		if (value)
559 			value[len - 1] = ' ';
560 		value = realloc(value, len + val_len + 1);
561 		if (!value) {
562 			fprintf(stderr,
563 				"Cannot malloc %zu bytes: %s\n",
564 				len, strerror(errno));
565 			return -1;
566 		}
567 
568 		memcpy(value + len, val, val_len);
569 		len += val_len;
570 		value[len++] = '\0';
571 	}
572 
573 	fw_env_write(name, value);
574 
575 	free(value);
576 
577 	return fw_env_close();
578 }
579 
580 /*
581  * Parse  a file  and configure the u-boot variables.
582  * The script file has a very simple format, as follows:
583  *
584  * Each line has a couple with name, value:
585  * <white spaces>variable_name<white spaces>variable_value
586  *
587  * Both variable_name and variable_value are interpreted as strings.
588  * Any character after <white spaces> and before ending \r\n is interpreted
589  * as variable's value (no comment allowed on these lines !)
590  *
591  * Comments are allowed if the first character in the line is #
592  *
593  * Returns -1 and sets errno error codes:
594  * 0	  - OK
595  * -1     - Error
596  */
597 int fw_parse_script(char *fname)
598 {
599 	FILE *fp;
600 	char dump[1024];	/* Maximum line length in the file */
601 	char *name;
602 	char *val;
603 	int lineno = 0;
604 	int len;
605 	int ret = 0;
606 
607 	if (fw_env_open()) {
608 		fprintf(stderr, "Error: environment not initialized\n");
609 		return -1;
610 	}
611 
612 	if (strcmp(fname, "-") == 0)
613 		fp = stdin;
614 	else {
615 		fp = fopen(fname, "r");
616 		if (fp == NULL) {
617 			fprintf(stderr, "I cannot open %s for reading\n",
618 				 fname);
619 			return -1;
620 		}
621 	}
622 
623 	while (fgets(dump, sizeof(dump), fp)) {
624 		lineno++;
625 		len = strlen(dump);
626 
627 		/*
628 		 * Read a whole line from the file. If the line is too long
629 		 * or is not terminated, reports an error and exit.
630 		 */
631 		if (dump[len - 1] != '\n') {
632 			fprintf(stderr,
633 			"Line %d not corrected terminated or too long\n",
634 				lineno);
635 			ret = -1;
636 			break;
637 		}
638 
639 		/* Drop ending line feed / carriage return */
640 		while (len > 0 && (dump[len - 1] == '\n' ||
641 				dump[len - 1] == '\r')) {
642 			dump[len - 1] = '\0';
643 			len--;
644 		}
645 
646 		/* Skip comment or empty lines */
647 		if ((len == 0) || dump[0] == '#')
648 			continue;
649 
650 		/*
651 		 * Search for variable's name,
652 		 * remove leading whitespaces
653 		 */
654 		name = fw_string_blank(dump, 1);
655 		if (!name)
656 			continue;
657 
658 		/* The first white space is the end of variable name */
659 		val = fw_string_blank(name, 0);
660 		len = strlen(name);
661 		if (val) {
662 			*val++ = '\0';
663 			if ((val - name) < len)
664 				val = fw_string_blank(val, 1);
665 			else
666 				val = NULL;
667 		}
668 
669 #ifdef DEBUG
670 		fprintf(stderr, "Setting %s : %s\n",
671 			name, val ? val : " removed");
672 #endif
673 
674 		if (env_flags_validate_type(name, val) < 0) {
675 			ret = -1;
676 			break;
677 		}
678 
679 		/*
680 		 * If there is an error setting a variable,
681 		 * try to save the environment and returns an error
682 		 */
683 		if (fw_env_write(name, val)) {
684 			fprintf(stderr,
685 			"fw_env_write returns with error : %s\n",
686 				strerror(errno));
687 			ret = -1;
688 			break;
689 		}
690 
691 	}
692 
693 	/* Close file if not stdin */
694 	if (strcmp(fname, "-") != 0)
695 		fclose(fp);
696 
697 	ret |= fw_env_close();
698 
699 	return ret;
700 
701 }
702 
703 /*
704  * Test for bad block on NAND, just returns 0 on NOR, on NAND:
705  * 0	- block is good
706  * > 0	- block is bad
707  * < 0	- failed to test
708  */
709 static int flash_bad_block (int fd, uint8_t mtd_type, loff_t *blockstart)
710 {
711 	if (mtd_type == MTD_NANDFLASH) {
712 		int badblock = ioctl (fd, MEMGETBADBLOCK, blockstart);
713 
714 		if (badblock < 0) {
715 			perror ("Cannot read bad block mark");
716 			return badblock;
717 		}
718 
719 		if (badblock) {
720 #ifdef DEBUG
721 			fprintf (stderr, "Bad block at 0x%llx, "
722 				 "skipping\n", *blockstart);
723 #endif
724 			return badblock;
725 		}
726 	}
727 
728 	return 0;
729 }
730 
731 /*
732  * Read data from flash at an offset into a provided buffer. On NAND it skips
733  * bad blocks but makes sure it stays within ENVSECTORS (dev) starting from
734  * the DEVOFFSET (dev) block. On NOR the loop is only run once.
735  */
736 static int flash_read_buf (int dev, int fd, void *buf, size_t count,
737 			   off_t offset, uint8_t mtd_type)
738 {
739 	size_t blocklen;	/* erase / write length - one block on NAND,
740 				   0 on NOR */
741 	size_t processed = 0;	/* progress counter */
742 	size_t readlen = count;	/* current read length */
743 	off_t top_of_range;	/* end of the last block we may use */
744 	off_t block_seek;	/* offset inside the current block to the start
745 				   of the data */
746 	loff_t blockstart;	/* running start of the current block -
747 				   MEMGETBADBLOCK needs 64 bits */
748 	int rc;
749 
750 	blockstart = (offset / DEVESIZE (dev)) * DEVESIZE (dev);
751 
752 	/* Offset inside a block */
753 	block_seek = offset - blockstart;
754 
755 	if (mtd_type == MTD_NANDFLASH) {
756 		/*
757 		 * NAND: calculate which blocks we are reading. We have
758 		 * to read one block at a time to skip bad blocks.
759 		 */
760 		blocklen = DEVESIZE (dev);
761 
762 		/*
763 		 * To calculate the top of the range, we have to use the
764 		 * global DEVOFFSET (dev), which can be different from offset
765 		 */
766 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
767 				ENVSECTORS (dev)) * blocklen;
768 
769 		/* Limit to one block for the first read */
770 		if (readlen > blocklen - block_seek)
771 			readlen = blocklen - block_seek;
772 	} else {
773 		blocklen = 0;
774 		top_of_range = offset + count;
775 	}
776 
777 	/* This only runs once on NOR flash */
778 	while (processed < count) {
779 		rc = flash_bad_block (fd, mtd_type, &blockstart);
780 		if (rc < 0)		/* block test failed */
781 			return -1;
782 
783 		if (blockstart + block_seek + readlen > top_of_range) {
784 			/* End of range is reached */
785 			fprintf (stderr,
786 				 "Too few good blocks within range\n");
787 			return -1;
788 		}
789 
790 		if (rc) {		/* block is bad */
791 			blockstart += blocklen;
792 			continue;
793 		}
794 
795 		/*
796 		 * If a block is bad, we retry in the next block at the same
797 		 * offset - see common/env_nand.c::writeenv()
798 		 */
799 		lseek (fd, blockstart + block_seek, SEEK_SET);
800 
801 		rc = read (fd, buf + processed, readlen);
802 		if (rc != readlen) {
803 			fprintf (stderr, "Read error on %s: %s\n",
804 				 DEVNAME (dev), strerror (errno));
805 			return -1;
806 		}
807 #ifdef DEBUG
808 		fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
809 			 rc, blockstart + block_seek, DEVNAME(dev));
810 #endif
811 		processed += readlen;
812 		readlen = min (blocklen, count - processed);
813 		block_seek = 0;
814 		blockstart += blocklen;
815 	}
816 
817 	return processed;
818 }
819 
820 /*
821  * Write count bytes at offset, but stay within ENVSECTORS (dev) sectors of
822  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
823  * erase and write the whole data at once.
824  */
825 static int flash_write_buf (int dev, int fd, void *buf, size_t count,
826 			    off_t offset, uint8_t mtd_type)
827 {
828 	void *data;
829 	struct erase_info_user erase;
830 	size_t blocklen;	/* length of NAND block / NOR erase sector */
831 	size_t erase_len;	/* whole area that can be erased - may include
832 				   bad blocks */
833 	size_t erasesize;	/* erase / write length - one block on NAND,
834 				   whole area on NOR */
835 	size_t processed = 0;	/* progress counter */
836 	size_t write_total;	/* total size to actually write - excluding
837 				   bad blocks */
838 	off_t erase_offset;	/* offset to the first erase block (aligned)
839 				   below offset */
840 	off_t block_seek;	/* offset inside the erase block to the start
841 				   of the data */
842 	off_t top_of_range;	/* end of the last block we may use */
843 	loff_t blockstart;	/* running start of the current block -
844 				   MEMGETBADBLOCK needs 64 bits */
845 	int rc;
846 
847 	/*
848 	 * For mtd devices only offset and size of the environment do matter
849 	 */
850 	if (mtd_type == MTD_ABSENT) {
851 		blocklen = count;
852 		top_of_range = offset + count;
853 		erase_len = blocklen;
854 		blockstart = offset;
855 		block_seek = 0;
856 		write_total = blocklen;
857 	} else {
858 		blocklen = DEVESIZE(dev);
859 
860 		top_of_range = ((DEVOFFSET(dev) / blocklen) +
861 					ENVSECTORS(dev)) * blocklen;
862 
863 		erase_offset = (offset / blocklen) * blocklen;
864 
865 		/* Maximum area we may use */
866 		erase_len = top_of_range - erase_offset;
867 
868 		blockstart = erase_offset;
869 		/* Offset inside a block */
870 		block_seek = offset - erase_offset;
871 
872 		/*
873 		 * Data size we actually write: from the start of the block
874 		 * to the start of the data, then count bytes of data, and
875 		 * to the end of the block
876 		 */
877 		write_total = ((block_seek + count + blocklen - 1) /
878 							blocklen) * blocklen;
879 	}
880 
881 	/*
882 	 * Support data anywhere within erase sectors: read out the complete
883 	 * area to be erased, replace the environment image, write the whole
884 	 * block back again.
885 	 */
886 	if (write_total > count) {
887 		data = malloc (erase_len);
888 		if (!data) {
889 			fprintf (stderr,
890 				 "Cannot malloc %zu bytes: %s\n",
891 				 erase_len, strerror (errno));
892 			return -1;
893 		}
894 
895 		rc = flash_read_buf (dev, fd, data, write_total, erase_offset,
896 				     mtd_type);
897 		if (write_total != rc)
898 			return -1;
899 
900 #ifdef DEBUG
901 		fprintf(stderr, "Preserving data ");
902 		if (block_seek != 0)
903 			fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
904 		if (block_seek + count != write_total) {
905 			if (block_seek != 0)
906 				fprintf(stderr, " and ");
907 			fprintf(stderr, "0x%lx - 0x%x",
908 				block_seek + count, write_total - 1);
909 		}
910 		fprintf(stderr, "\n");
911 #endif
912 		/* Overwrite the old environment */
913 		memcpy (data + block_seek, buf, count);
914 	} else {
915 		/*
916 		 * We get here, iff offset is block-aligned and count is a
917 		 * multiple of blocklen - see write_total calculation above
918 		 */
919 		data = buf;
920 	}
921 
922 	if (mtd_type == MTD_NANDFLASH) {
923 		/*
924 		 * NAND: calculate which blocks we are writing. We have
925 		 * to write one block at a time to skip bad blocks.
926 		 */
927 		erasesize = blocklen;
928 	} else {
929 		erasesize = erase_len;
930 	}
931 
932 	erase.length = erasesize;
933 
934 	/* This only runs once on NOR flash and SPI-dataflash */
935 	while (processed < write_total) {
936 		rc = flash_bad_block (fd, mtd_type, &blockstart);
937 		if (rc < 0)		/* block test failed */
938 			return rc;
939 
940 		if (blockstart + erasesize > top_of_range) {
941 			fprintf (stderr, "End of range reached, aborting\n");
942 			return -1;
943 		}
944 
945 		if (rc) {		/* block is bad */
946 			blockstart += blocklen;
947 			continue;
948 		}
949 
950 		if (mtd_type != MTD_ABSENT) {
951 			erase.start = blockstart;
952 			ioctl(fd, MEMUNLOCK, &erase);
953 			/* These do not need an explicit erase cycle */
954 			if (mtd_type != MTD_DATAFLASH)
955 				if (ioctl(fd, MEMERASE, &erase) != 0) {
956 					fprintf(stderr,
957 						"MTD erase error on %s: %s\n",
958 						DEVNAME(dev), strerror(errno));
959 					return -1;
960 				}
961 		}
962 
963 		if (lseek (fd, blockstart, SEEK_SET) == -1) {
964 			fprintf (stderr,
965 				 "Seek error on %s: %s\n",
966 				 DEVNAME (dev), strerror (errno));
967 			return -1;
968 		}
969 
970 #ifdef DEBUG
971 		fprintf(stderr, "Write 0x%x bytes at 0x%llx\n", erasesize,
972 			blockstart);
973 #endif
974 		if (write (fd, data + processed, erasesize) != erasesize) {
975 			fprintf (stderr, "Write error on %s: %s\n",
976 				 DEVNAME (dev), strerror (errno));
977 			return -1;
978 		}
979 
980 		if (mtd_type != MTD_ABSENT)
981 			ioctl(fd, MEMLOCK, &erase);
982 
983 		processed  += erasesize;
984 		block_seek = 0;
985 		blockstart += erasesize;
986 	}
987 
988 	if (write_total > count)
989 		free (data);
990 
991 	return processed;
992 }
993 
994 /*
995  * Set obsolete flag at offset - NOR flash only
996  */
997 static int flash_flag_obsolete (int dev, int fd, off_t offset)
998 {
999 	int rc;
1000 	struct erase_info_user erase;
1001 
1002 	erase.start  = DEVOFFSET (dev);
1003 	erase.length = DEVESIZE (dev);
1004 	/* This relies on the fact, that obsolete_flag == 0 */
1005 	rc = lseek (fd, offset, SEEK_SET);
1006 	if (rc < 0) {
1007 		fprintf (stderr, "Cannot seek to set the flag on %s \n",
1008 			 DEVNAME (dev));
1009 		return rc;
1010 	}
1011 	ioctl (fd, MEMUNLOCK, &erase);
1012 	rc = write (fd, &obsolete_flag, sizeof (obsolete_flag));
1013 	ioctl (fd, MEMLOCK, &erase);
1014 	if (rc < 0)
1015 		perror ("Could not set obsolete flag");
1016 
1017 	return rc;
1018 }
1019 
1020 /* Encrypt or decrypt the environment before writing or reading it. */
1021 static int env_aes_cbc_crypt(char *payload, const int enc)
1022 {
1023 	uint8_t *data = (uint8_t *)payload;
1024 	const int len = getenvsize();
1025 	uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
1026 	uint32_t aes_blocks;
1027 
1028 	/* First we expand the key. */
1029 	aes_expand_key(aes_key, key_exp);
1030 
1031 	/* Calculate the number of AES blocks to encrypt. */
1032 	aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
1033 
1034 	if (enc)
1035 		aes_cbc_encrypt_blocks(key_exp, data, data, aes_blocks);
1036 	else
1037 		aes_cbc_decrypt_blocks(key_exp, data, data, aes_blocks);
1038 
1039 	return 0;
1040 }
1041 
1042 static int flash_write (int fd_current, int fd_target, int dev_target)
1043 {
1044 	int rc;
1045 
1046 	switch (environment.flag_scheme) {
1047 	case FLAG_NONE:
1048 		break;
1049 	case FLAG_INCREMENTAL:
1050 		(*environment.flags)++;
1051 		break;
1052 	case FLAG_BOOLEAN:
1053 		*environment.flags = active_flag;
1054 		break;
1055 	default:
1056 		fprintf (stderr, "Unimplemented flash scheme %u \n",
1057 			 environment.flag_scheme);
1058 		return -1;
1059 	}
1060 
1061 #ifdef DEBUG
1062 	fprintf(stderr, "Writing new environment at 0x%lx on %s\n",
1063 		DEVOFFSET (dev_target), DEVNAME (dev_target));
1064 #endif
1065 
1066 	rc = flash_write_buf(dev_target, fd_target, environment.image,
1067 			      CUR_ENVSIZE, DEVOFFSET(dev_target),
1068 			      DEVTYPE(dev_target));
1069 	if (rc < 0)
1070 		return rc;
1071 
1072 	if (environment.flag_scheme == FLAG_BOOLEAN) {
1073 		/* Have to set obsolete flag */
1074 		off_t offset = DEVOFFSET (dev_current) +
1075 			offsetof (struct env_image_redundant, flags);
1076 #ifdef DEBUG
1077 		fprintf(stderr,
1078 			"Setting obsolete flag in environment at 0x%lx on %s\n",
1079 			DEVOFFSET (dev_current), DEVNAME (dev_current));
1080 #endif
1081 		flash_flag_obsolete (dev_current, fd_current, offset);
1082 	}
1083 
1084 	return 0;
1085 }
1086 
1087 static int flash_read (int fd)
1088 {
1089 	struct mtd_info_user mtdinfo;
1090 	struct stat st;
1091 	int rc;
1092 
1093 	rc = fstat(fd, &st);
1094 	if (rc < 0) {
1095 		fprintf(stderr, "Cannot stat the file %s\n",
1096 			DEVNAME(dev_current));
1097 		return -1;
1098 	}
1099 
1100 	if (S_ISCHR(st.st_mode)) {
1101 		rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1102 		if (rc < 0) {
1103 			fprintf(stderr, "Cannot get MTD information for %s\n",
1104 				DEVNAME(dev_current));
1105 			return -1;
1106 		}
1107 		if (mtdinfo.type != MTD_NORFLASH &&
1108 		    mtdinfo.type != MTD_NANDFLASH &&
1109 		    mtdinfo.type != MTD_DATAFLASH &&
1110 		    mtdinfo.type != MTD_UBIVOLUME) {
1111 			fprintf (stderr, "Unsupported flash type %u on %s\n",
1112 				 mtdinfo.type, DEVNAME(dev_current));
1113 			return -1;
1114 		}
1115 	} else {
1116 		memset(&mtdinfo, 0, sizeof(mtdinfo));
1117 		mtdinfo.type = MTD_ABSENT;
1118 	}
1119 
1120 	DEVTYPE(dev_current) = mtdinfo.type;
1121 
1122 	rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1123 			     DEVOFFSET (dev_current), mtdinfo.type);
1124 	if (rc != CUR_ENVSIZE)
1125 		return -1;
1126 
1127 	return 0;
1128 }
1129 
1130 static int flash_io (int mode)
1131 {
1132 	int fd_current, fd_target, rc, dev_target;
1133 
1134 	/* dev_current: fd_current, erase_current */
1135 	fd_current = open (DEVNAME (dev_current), mode);
1136 	if (fd_current < 0) {
1137 		fprintf (stderr,
1138 			 "Can't open %s: %s\n",
1139 			 DEVNAME (dev_current), strerror (errno));
1140 		return -1;
1141 	}
1142 
1143 	if (mode == O_RDWR) {
1144 		if (HaveRedundEnv) {
1145 			/* switch to next partition for writing */
1146 			dev_target = !dev_current;
1147 			/* dev_target: fd_target, erase_target */
1148 			fd_target = open (DEVNAME (dev_target), mode);
1149 			if (fd_target < 0) {
1150 				fprintf (stderr,
1151 					 "Can't open %s: %s\n",
1152 					 DEVNAME (dev_target),
1153 					 strerror (errno));
1154 				rc = -1;
1155 				goto exit;
1156 			}
1157 		} else {
1158 			dev_target = dev_current;
1159 			fd_target = fd_current;
1160 		}
1161 
1162 		rc = flash_write (fd_current, fd_target, dev_target);
1163 
1164 		if (HaveRedundEnv) {
1165 			if (close (fd_target)) {
1166 				fprintf (stderr,
1167 					"I/O error on %s: %s\n",
1168 					DEVNAME (dev_target),
1169 					strerror (errno));
1170 				rc = -1;
1171 			}
1172 		}
1173 	} else {
1174 		rc = flash_read (fd_current);
1175 	}
1176 
1177 exit:
1178 	if (close (fd_current)) {
1179 		fprintf (stderr,
1180 			 "I/O error on %s: %s\n",
1181 			 DEVNAME (dev_current), strerror (errno));
1182 		return -1;
1183 	}
1184 
1185 	return rc;
1186 }
1187 
1188 /*
1189  * s1 is either a simple 'name', or a 'name=value' pair.
1190  * s2 is a 'name=value' pair.
1191  * If the names match, return the value of s2, else NULL.
1192  */
1193 
1194 static char *envmatch (char * s1, char * s2)
1195 {
1196 	if (s1 == NULL || s2 == NULL)
1197 		return NULL;
1198 
1199 	while (*s1 == *s2++)
1200 		if (*s1++ == '=')
1201 			return s2;
1202 	if (*s1 == '\0' && *(s2 - 1) == '=')
1203 		return s2;
1204 	return NULL;
1205 }
1206 
1207 /*
1208  * Prevent confusion if running from erased flash memory
1209  */
1210 int fw_env_open(void)
1211 {
1212 	int crc0, crc0_ok;
1213 	unsigned char flag0;
1214 	void *addr0;
1215 
1216 	int crc1, crc1_ok;
1217 	unsigned char flag1;
1218 	void *addr1;
1219 
1220 	int ret;
1221 
1222 	struct env_image_single *single;
1223 	struct env_image_redundant *redundant;
1224 
1225 	if (parse_config ())		/* should fill envdevices */
1226 		return -1;
1227 
1228 	addr0 = calloc(1, CUR_ENVSIZE);
1229 	if (addr0 == NULL) {
1230 		fprintf(stderr,
1231 			"Not enough memory for environment (%ld bytes)\n",
1232 			CUR_ENVSIZE);
1233 		return -1;
1234 	}
1235 
1236 	/* read environment from FLASH to local buffer */
1237 	environment.image = addr0;
1238 
1239 	if (HaveRedundEnv) {
1240 		redundant = addr0;
1241 		environment.crc		= &redundant->crc;
1242 		environment.flags	= &redundant->flags;
1243 		environment.data	= redundant->data;
1244 	} else {
1245 		single = addr0;
1246 		environment.crc		= &single->crc;
1247 		environment.flags	= NULL;
1248 		environment.data	= single->data;
1249 	}
1250 
1251 	dev_current = 0;
1252 	if (flash_io (O_RDONLY))
1253 		return -1;
1254 
1255 	crc0 = crc32 (0, (uint8_t *) environment.data, ENV_SIZE);
1256 
1257 	if (aes_flag) {
1258 		ret = env_aes_cbc_crypt(environment.data, 0);
1259 		if (ret)
1260 			return ret;
1261 	}
1262 
1263 	crc0_ok = (crc0 == *environment.crc);
1264 	if (!HaveRedundEnv) {
1265 		if (!crc0_ok) {
1266 			fprintf (stderr,
1267 				"Warning: Bad CRC, using default environment\n");
1268 			memcpy(environment.data, default_environment, sizeof default_environment);
1269 		}
1270 	} else {
1271 		flag0 = *environment.flags;
1272 
1273 		dev_current = 1;
1274 		addr1 = calloc(1, CUR_ENVSIZE);
1275 		if (addr1 == NULL) {
1276 			fprintf(stderr,
1277 				"Not enough memory for environment (%ld bytes)\n",
1278 				CUR_ENVSIZE);
1279 			return -1;
1280 		}
1281 		redundant = addr1;
1282 
1283 		/*
1284 		 * have to set environment.image for flash_read(), careful -
1285 		 * other pointers in environment still point inside addr0
1286 		 */
1287 		environment.image = addr1;
1288 		if (flash_io (O_RDONLY))
1289 			return -1;
1290 
1291 		/* Check flag scheme compatibility */
1292 		if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1293 		    DEVTYPE(!dev_current) == MTD_NORFLASH) {
1294 			environment.flag_scheme = FLAG_BOOLEAN;
1295 		} else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1296 			   DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1297 			environment.flag_scheme = FLAG_INCREMENTAL;
1298 		} else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1299 			   DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1300 			environment.flag_scheme = FLAG_BOOLEAN;
1301 		} else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1302 			   DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1303 			environment.flag_scheme = FLAG_INCREMENTAL;
1304 		} else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1305 			   DEVTYPE(!dev_current) == MTD_ABSENT) {
1306 			environment.flag_scheme = FLAG_INCREMENTAL;
1307 		} else {
1308 			fprintf (stderr, "Incompatible flash types!\n");
1309 			return -1;
1310 		}
1311 
1312 		crc1 = crc32 (0, (uint8_t *) redundant->data, ENV_SIZE);
1313 
1314 		if (aes_flag) {
1315 			ret = env_aes_cbc_crypt(redundant->data, 0);
1316 			if (ret)
1317 				return ret;
1318 		}
1319 
1320 		crc1_ok = (crc1 == redundant->crc);
1321 		flag1 = redundant->flags;
1322 
1323 		if (crc0_ok && !crc1_ok) {
1324 			dev_current = 0;
1325 		} else if (!crc0_ok && crc1_ok) {
1326 			dev_current = 1;
1327 		} else if (!crc0_ok && !crc1_ok) {
1328 			fprintf (stderr,
1329 				"Warning: Bad CRC, using default environment\n");
1330 			memcpy (environment.data, default_environment,
1331 				sizeof default_environment);
1332 			dev_current = 0;
1333 		} else {
1334 			switch (environment.flag_scheme) {
1335 			case FLAG_BOOLEAN:
1336 				if (flag0 == active_flag &&
1337 				    flag1 == obsolete_flag) {
1338 					dev_current = 0;
1339 				} else if (flag0 == obsolete_flag &&
1340 					   flag1 == active_flag) {
1341 					dev_current = 1;
1342 				} else if (flag0 == flag1) {
1343 					dev_current = 0;
1344 				} else if (flag0 == 0xFF) {
1345 					dev_current = 0;
1346 				} else if (flag1 == 0xFF) {
1347 					dev_current = 1;
1348 				} else {
1349 					dev_current = 0;
1350 				}
1351 				break;
1352 			case FLAG_INCREMENTAL:
1353 				if (flag0 == 255 && flag1 == 0)
1354 					dev_current = 1;
1355 				else if ((flag1 == 255 && flag0 == 0) ||
1356 					 flag0 >= flag1)
1357 					dev_current = 0;
1358 				else /* flag1 > flag0 */
1359 					dev_current = 1;
1360 				break;
1361 			default:
1362 				fprintf (stderr, "Unknown flag scheme %u \n",
1363 					 environment.flag_scheme);
1364 				return -1;
1365 			}
1366 		}
1367 
1368 		/*
1369 		 * If we are reading, we don't need the flag and the CRC any
1370 		 * more, if we are writing, we will re-calculate CRC and update
1371 		 * flags before writing out
1372 		 */
1373 		if (dev_current) {
1374 			environment.image	= addr1;
1375 			environment.crc		= &redundant->crc;
1376 			environment.flags	= &redundant->flags;
1377 			environment.data	= redundant->data;
1378 			free (addr0);
1379 		} else {
1380 			environment.image	= addr0;
1381 			/* Other pointers are already set */
1382 			free (addr1);
1383 		}
1384 #ifdef DEBUG
1385 		fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1386 #endif
1387 	}
1388 	return 0;
1389 }
1390 
1391 
1392 static int parse_config ()
1393 {
1394 	struct stat st;
1395 
1396 #if defined(CONFIG_FILE)
1397 	/* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1398 	if (get_config (config_file)) {
1399 		fprintf (stderr,
1400 			"Cannot parse config file '%s': %s\n", config_file, strerror (errno));
1401 		return -1;
1402 	}
1403 #else
1404 	DEVNAME (0) = DEVICE1_NAME;
1405 	DEVOFFSET (0) = DEVICE1_OFFSET;
1406 	ENVSIZE (0) = ENV1_SIZE;
1407 	/* Default values are: erase-size=env-size */
1408 	DEVESIZE (0) = ENVSIZE (0);
1409 	/* #sectors=env-size/erase-size (rounded up) */
1410 	ENVSECTORS (0) = (ENVSIZE(0) + DEVESIZE(0) - 1) / DEVESIZE(0);
1411 #ifdef DEVICE1_ESIZE
1412 	DEVESIZE (0) = DEVICE1_ESIZE;
1413 #endif
1414 #ifdef DEVICE1_ENVSECTORS
1415 	ENVSECTORS (0) = DEVICE1_ENVSECTORS;
1416 #endif
1417 
1418 #ifdef HAVE_REDUND
1419 	DEVNAME (1) = DEVICE2_NAME;
1420 	DEVOFFSET (1) = DEVICE2_OFFSET;
1421 	ENVSIZE (1) = ENV2_SIZE;
1422 	/* Default values are: erase-size=env-size */
1423 	DEVESIZE (1) = ENVSIZE (1);
1424 	/* #sectors=env-size/erase-size (rounded up) */
1425 	ENVSECTORS (1) = (ENVSIZE(1) + DEVESIZE(1) - 1) / DEVESIZE(1);
1426 #ifdef DEVICE2_ESIZE
1427 	DEVESIZE (1) = DEVICE2_ESIZE;
1428 #endif
1429 #ifdef DEVICE2_ENVSECTORS
1430 	ENVSECTORS (1) = DEVICE2_ENVSECTORS;
1431 #endif
1432 	HaveRedundEnv = 1;
1433 #endif
1434 #endif
1435 	if (stat (DEVNAME (0), &st)) {
1436 		fprintf (stderr,
1437 			"Cannot access MTD device %s: %s\n",
1438 			DEVNAME (0), strerror (errno));
1439 		return -1;
1440 	}
1441 
1442 	if (HaveRedundEnv && stat (DEVNAME (1), &st)) {
1443 		fprintf (stderr,
1444 			"Cannot access MTD device %s: %s\n",
1445 			DEVNAME (1), strerror (errno));
1446 		return -1;
1447 	}
1448 	return 0;
1449 }
1450 
1451 #if defined(CONFIG_FILE)
1452 static int get_config (char *fname)
1453 {
1454 	FILE *fp;
1455 	int i = 0;
1456 	int rc;
1457 	char dump[128];
1458 	char *devname;
1459 
1460 	fp = fopen (fname, "r");
1461 	if (fp == NULL)
1462 		return -1;
1463 
1464 	while (i < 2 && fgets (dump, sizeof (dump), fp)) {
1465 		/* Skip incomplete conversions and comment strings */
1466 		if (dump[0] == '#')
1467 			continue;
1468 
1469 		rc = sscanf (dump, "%ms %lx %lx %lx %lx",
1470 			     &devname,
1471 			     &DEVOFFSET (i),
1472 			     &ENVSIZE (i),
1473 			     &DEVESIZE (i),
1474 			     &ENVSECTORS (i));
1475 
1476 		if (rc < 3)
1477 			continue;
1478 
1479 		DEVNAME(i) = devname;
1480 
1481 		if (rc < 4)
1482 			/* Assume the erase size is the same as the env-size */
1483 			DEVESIZE(i) = ENVSIZE(i);
1484 
1485 		if (rc < 5)
1486 			/* Assume enough env sectors to cover the environment */
1487 			ENVSECTORS (i) = (ENVSIZE(i) + DEVESIZE(i) - 1) / DEVESIZE(i);
1488 
1489 		i++;
1490 	}
1491 	fclose (fp);
1492 
1493 	HaveRedundEnv = i - 1;
1494 	if (!i) {			/* No valid entries found */
1495 		errno = EINVAL;
1496 		return -1;
1497 	} else
1498 		return 0;
1499 }
1500 #endif
1501