tools/env/fw_env.c

   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
 131 static int is_ubi_devname(const char *devname)
 132 {
 133         return !strncmp(devname, UBI_DEV_START, sizeof(UBI_DEV_START) - 1);
 134 }
 135
 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
 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
 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
 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
 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
 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
 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
 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
 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
 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  */
 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  */
 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  */
 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  */
 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
 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  */
 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  */
 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  */
 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  */
 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  */
 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  */
 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                 if (rc != readlen) {
 955                         fprintf(stderr, "Read error on %s: "
 956                                 "Attempted to read %d bytes but got %d\n",
 957                                 DEVNAME(dev), readlen, rc);
 958                         return -1;
 959                 }
 960 #ifdef DEBUG
 961                 fprintf(stderr, "Read 0x%x bytes at 0x%llx on %s\n",
 962                         rc, (unsigned long long)blockstart + block_seek,
 963                         DEVNAME(dev));
 964 #endif
 965                 processed += readlen;
 966                 readlen = min(blocklen, count - processed);
 967                 block_seek = 0;
 968                 blockstart += blocklen;
 969         }
 970
 971         return processed;
 972 }
 973
 974 /*
 975  * Write count bytes from begin of environment, but stay within
 976  * ENVSECTORS(dev) sectors of
 977  * DEVOFFSET (dev). Similar to the read case above, on NOR and dataflash we
 978  * erase and write the whole data at once.
 979  */
 980 static int flash_write_buf(int dev, int fd, void *buf, size_t count)
 981 {
 982         void *data;
 983         struct erase_info_user erase;
 984         size_t blocklen;        /* length of NAND block / NOR erase sector */
 985         size_t erase_len;       /* whole area that can be erased - may include
 986                                    bad blocks */
 987         size_t erasesize;       /* erase / write length - one block on NAND,
 988                                    whole area on NOR */
 989         size_t processed = 0;   /* progress counter */
 990         size_t write_total;     /* total size to actually write - excluding
 991                                    bad blocks */
 992         off_t erase_offset;     /* offset to the first erase block (aligned)
 993                                    below offset */
 994         off_t block_seek;       /* offset inside the erase block to the start
 995                                    of the data */
 996         loff_t blockstart;      /* running start of the current block -
 997                                    MEMGETBADBLOCK needs 64 bits */
 998         int rc;
 999
1000         /*
1001          * For mtd devices only offset and size of the environment do matter
1002          */
1003         if (DEVTYPE(dev) == MTD_ABSENT) {
1004                 blocklen = count;
1005                 erase_len = blocklen;
1006                 blockstart = DEVOFFSET(dev);
1007                 block_seek = 0;
1008                 write_total = blocklen;
1009         } else {
1010                 blocklen = DEVESIZE(dev);
1011
1012                 erase_offset = DEVOFFSET(dev);
1013
1014                 /* Maximum area we may use */
1015                 erase_len = environment_end(dev) - erase_offset;
1016
1017                 blockstart = erase_offset;
1018
1019                 /* Offset inside a block */
1020                 block_seek = DEVOFFSET(dev) - erase_offset;
1021
1022                 /*
1023                  * Data size we actually write: from the start of the block
1024                  * to the start of the data, then count bytes of data, and
1025                  * to the end of the block
1026                  */
1027                 write_total = ((block_seek + count + blocklen - 1) /
1028                                blocklen) * blocklen;
1029         }
1030
1031         /*
1032          * Support data anywhere within erase sectors: read out the complete
1033          * area to be erased, replace the environment image, write the whole
1034          * block back again.
1035          */
1036         if (write_total > count) {
1037                 data = malloc(erase_len);
1038                 if (!data) {
1039                         fprintf(stderr,
1040                                 "Cannot malloc %zu bytes: %s\n",
1041                                 erase_len, strerror(errno));
1042                         return -1;
1043                 }
1044
1045                 rc = flash_read_buf(dev, fd, data, write_total, erase_offset);
1046                 if (write_total != rc)
1047                         return -1;
1048
1049 #ifdef DEBUG
1050                 fprintf(stderr, "Preserving data ");
1051                 if (block_seek != 0)
1052                         fprintf(stderr, "0x%x - 0x%lx", 0, block_seek - 1);
1053                 if (block_seek + count != write_total) {
1054                         if (block_seek != 0)
1055                                 fprintf(stderr, " and ");
1056                         fprintf(stderr, "0x%lx - 0x%lx",
1057                                 (unsigned long)block_seek + count,
1058                                 (unsigned long)write_total - 1);
1059                 }
1060                 fprintf(stderr, "\n");
1061 #endif
1062                 /* Overwrite the old environment */
1063                 memcpy(data + block_seek, buf, count);
1064         } else {
1065                 /*
1066                  * We get here, iff offset is block-aligned and count is a
1067                  * multiple of blocklen - see write_total calculation above
1068                  */
1069                 data = buf;
1070         }
1071
1072         if (DEVTYPE(dev) == MTD_NANDFLASH) {
1073                 /*
1074                  * NAND: calculate which blocks we are writing. We have
1075                  * to write one block at a time to skip bad blocks.
1076                  */
1077                 erasesize = blocklen;
1078         } else {
1079                 erasesize = erase_len;
1080         }
1081
1082         erase.length = erasesize;
1083
1084         /* This only runs once on NOR flash and SPI-dataflash */
1085         while (processed < write_total) {
1086                 rc = flash_bad_block(fd, DEVTYPE(dev), blockstart);
1087                 if (rc < 0)     /* block test failed */
1088                         return rc;
1089
1090                 if (blockstart + erasesize > environment_end(dev)) {
1091                         fprintf(stderr, "End of range reached, aborting\n");
1092                         return -1;
1093                 }
1094
1095                 if (rc) {       /* block is bad */
1096                         blockstart += blocklen;
1097                         continue;
1098                 }
1099
1100                 if (DEVTYPE(dev) != MTD_ABSENT) {
1101                         erase.start = blockstart;
1102                         ioctl(fd, MEMUNLOCK, &erase);
1103                         /* These do not need an explicit erase cycle */
1104                         if (DEVTYPE(dev) != MTD_DATAFLASH)
1105                                 if (ioctl(fd, MEMERASE, &erase) != 0) {
1106                                         fprintf(stderr,
1107                                                 "MTD erase error on %s: %s\n",
1108                                                 DEVNAME(dev), strerror(errno));
1109                                         return -1;
1110                                 }
1111                 }
1112
1113                 if (lseek(fd, blockstart, SEEK_SET) == -1) {
1114                         fprintf(stderr,
1115                                 "Seek error on %s: %s\n",
1116                                 DEVNAME(dev), strerror(errno));
1117                         return -1;
1118                 }
1119 #ifdef DEBUG
1120                 fprintf(stderr, "Write 0x%llx bytes at 0x%llx\n",
1121                         (unsigned long long)erasesize,
1122                         (unsigned long long)blockstart);
1123 #endif
1124                 if (write(fd, data + processed, erasesize) != erasesize) {
1125                         fprintf(stderr, "Write error on %s: %s\n",
1126                                 DEVNAME(dev), strerror(errno));
1127                         return -1;
1128                 }
1129
1130                 if (DEVTYPE(dev) != MTD_ABSENT)
1131                         ioctl(fd, MEMLOCK, &erase);
1132
1133                 processed += erasesize;
1134                 block_seek = 0;
1135                 blockstart += erasesize;
1136         }
1137
1138         if (write_total > count)
1139                 free(data);
1140
1141         return processed;
1142 }
1143
1144 /*
1145  * Set obsolete flag at offset - NOR flash only
1146  */
1147 static int flash_flag_obsolete(int dev, int fd, off_t offset)
1148 {
1149         int rc;
1150         struct erase_info_user erase;
1151         char tmp = ENV_REDUND_OBSOLETE;
1152
1153         erase.start = DEVOFFSET(dev);
1154         erase.length = DEVESIZE(dev);
1155         /* This relies on the fact, that ENV_REDUND_OBSOLETE == 0 */
1156         rc = lseek(fd, offset, SEEK_SET);
1157         if (rc < 0) {
1158                 fprintf(stderr, "Cannot seek to set the flag on %s\n",
1159                         DEVNAME(dev));
1160                 return rc;
1161         }
1162         ioctl(fd, MEMUNLOCK, &erase);
1163         rc = write(fd, &tmp, sizeof(tmp));
1164         ioctl(fd, MEMLOCK, &erase);
1165         if (rc < 0)
1166                 perror("Could not set obsolete flag");
1167
1168         return rc;
1169 }
1170
1171 static int flash_write(int fd_current, int fd_target, int dev_target)
1172 {
1173         int rc;
1174
1175         switch (environment.flag_scheme) {
1176         case FLAG_NONE:
1177                 break;
1178         case FLAG_INCREMENTAL:
1179                 (*environment.flags)++;
1180                 break;
1181         case FLAG_BOOLEAN:
1182                 *environment.flags = ENV_REDUND_ACTIVE;
1183                 break;
1184         default:
1185                 fprintf(stderr, "Unimplemented flash scheme %u\n",
1186                         environment.flag_scheme);
1187                 return -1;
1188         }
1189
1190 #ifdef DEBUG
1191         fprintf(stderr, "Writing new environment at 0x%llx on %s\n",
1192                 DEVOFFSET(dev_target), DEVNAME(dev_target));
1193 #endif
1194
1195         if (IS_UBI(dev_target)) {
1196                 if (ubi_update_start(fd_target, CUR_ENVSIZE) < 0)
1197                         return 0;
1198                 return ubi_write(fd_target, environment.image, CUR_ENVSIZE);
1199         }
1200
1201         rc = flash_write_buf(dev_target, fd_target, environment.image,
1202                              CUR_ENVSIZE);
1203         if (rc < 0)
1204                 return rc;
1205
1206         if (environment.flag_scheme == FLAG_BOOLEAN) {
1207                 /* Have to set obsolete flag */
1208                 off_t offset = DEVOFFSET(dev_current) +
1209                     offsetof(struct env_image_redundant, flags);
1210 #ifdef DEBUG
1211                 fprintf(stderr,
1212                         "Setting obsolete flag in environment at 0x%llx on %s\n",
1213                         DEVOFFSET(dev_current), DEVNAME(dev_current));
1214 #endif
1215                 flash_flag_obsolete(dev_current, fd_current, offset);
1216         }
1217
1218         return 0;
1219 }
1220
1221 static int flash_read(int fd)
1222 {
1223         int rc;
1224
1225         if (IS_UBI(dev_current)) {
1226                 DEVTYPE(dev_current) = MTD_ABSENT;
1227
1228                 return ubi_read(fd, environment.image, CUR_ENVSIZE);
1229         }
1230
1231         rc = flash_read_buf(dev_current, fd, environment.image, CUR_ENVSIZE,
1232                             DEVOFFSET(dev_current));
1233         if (rc != CUR_ENVSIZE)
1234                 return -1;
1235
1236         return 0;
1237 }
1238
1239 static int flash_open_tempfile(const char **dname, const char **target_temp)
1240 {
1241         char *dup_name = strdup(DEVNAME(dev_current));
1242         char *temp_name = NULL;
1243         int rc = -1;
1244
1245         if (!dup_name)
1246                 return -1;
1247
1248         *dname = dirname(dup_name);
1249         if (!*dname)
1250                 goto err;
1251
1252         rc = asprintf(&temp_name, "%s/XXXXXX", *dname);
1253         if (rc == -1)
1254                 goto err;
1255
1256         rc = mkstemp(temp_name);
1257         if (rc == -1) {
1258                 /* fall back to in place write */
1259                 fprintf(stderr,
1260                         "Can't create %s: %s\n", temp_name, strerror(errno));
1261                 free(temp_name);
1262         } else {
1263                 *target_temp = temp_name;
1264                 /* deliberately leak dup_name as dname /might/ point into
1265                  * it and we need it for our caller
1266                  */
1267                 dup_name = NULL;
1268         }
1269
1270 err:
1271         if (dup_name)
1272                 free(dup_name);
1273
1274         return rc;
1275 }
1276
1277 static int flash_io_write(int fd_current)
1278 {
1279         int fd_target = -1, rc, dev_target;
1280         const char *dname, *target_temp = NULL;
1281
1282         if (have_redund_env) {
1283                 /* switch to next partition for writing */
1284                 dev_target = !dev_current;
1285                 /* dev_target: fd_target, erase_target */
1286                 fd_target = open(DEVNAME(dev_target), O_RDWR);
1287                 if (fd_target < 0) {
1288                         fprintf(stderr,
1289                                 "Can't open %s: %s\n",
1290                                 DEVNAME(dev_target), strerror(errno));
1291                         rc = -1;
1292                         goto exit;
1293                 }
1294         } else {
1295                 struct stat sb;
1296
1297                 if (fstat(fd_current, &sb) == 0 && S_ISREG(sb.st_mode)) {
1298                         /* if any part of flash_open_tempfile() fails we fall
1299                          * back to in-place writes
1300                          */
1301                         fd_target = flash_open_tempfile(&dname, &target_temp);
1302                 }
1303                 dev_target = dev_current;
1304                 if (fd_target == -1)
1305                         fd_target = fd_current;
1306         }
1307
1308         rc = flash_write(fd_current, fd_target, dev_target);
1309
1310         if (fsync(fd_current) && !(errno == EINVAL || errno == EROFS)) {
1311                 fprintf(stderr,
1312                         "fsync failed on %s: %s\n",
1313                         DEVNAME(dev_current), strerror(errno));
1314         }
1315
1316         if (fd_current != fd_target) {
1317                 if (fsync(fd_target) &&
1318                     !(errno == EINVAL || errno == EROFS)) {
1319                         fprintf(stderr,
1320                                 "fsync failed on %s: %s\n",
1321                                 DEVNAME(dev_current), strerror(errno));
1322                 }
1323
1324                 if (close(fd_target)) {
1325                         fprintf(stderr,
1326                                 "I/O error on %s: %s\n",
1327                                 DEVNAME(dev_target), strerror(errno));
1328                         rc = -1;
1329                 }
1330
1331                 if (rc >= 0 && target_temp) {
1332                         int dir_fd;
1333
1334                         dir_fd = open(dname, O_DIRECTORY | O_RDONLY);
1335                         if (dir_fd == -1)
1336                                 fprintf(stderr,
1337                                         "Can't open %s: %s\n",
1338                                         dname, strerror(errno));
1339
1340                         if (rename(target_temp, DEVNAME(dev_target))) {
1341                                 fprintf(stderr,
1342                                         "rename failed %s => %s: %s\n",
1343                                         target_temp, DEVNAME(dev_target),
1344                                         strerror(errno));
1345                                 rc = -1;
1346                         }
1347
1348                         if (dir_fd != -1 && fsync(dir_fd))
1349                                 fprintf(stderr,
1350                                         "fsync failed on %s: %s\n",
1351                                         dname, strerror(errno));
1352
1353                         if (dir_fd != -1 && close(dir_fd))
1354                                 fprintf(stderr,
1355                                         "I/O error on %s: %s\n",
1356                                         dname, strerror(errno));
1357                 }
1358         }
1359  exit:
1360         return rc;
1361 }
1362
1363 static int flash_io(int mode)
1364 {
1365         int fd_current, rc;
1366
1367         /* dev_current: fd_current, erase_current */
1368         fd_current = open(DEVNAME(dev_current), mode);
1369         if (fd_current < 0) {
1370                 fprintf(stderr,
1371                         "Can't open %s: %s\n",
1372                         DEVNAME(dev_current), strerror(errno));
1373                 return -1;
1374         }
1375
1376         if (mode == O_RDWR) {
1377                 rc = flash_io_write(fd_current);
1378         } else {
1379                 rc = flash_read(fd_current);
1380         }
1381
1382         if (close(fd_current)) {
1383                 fprintf(stderr,
1384                         "I/O error on %s: %s\n",
1385                         DEVNAME(dev_current), strerror(errno));
1386                 return -1;
1387         }
1388
1389         return rc;
1390 }
1391
1392 /*
1393  * Prevent confusion if running from erased flash memory
1394  */
1395 int fw_env_open(struct env_opts *opts)
1396 {
1397         int crc0, crc0_ok;
1398         unsigned char flag0;
1399         void *addr0 = NULL;
1400
1401         int crc1, crc1_ok;
1402         unsigned char flag1;
1403         void *addr1 = NULL;
1404
1405         int ret;
1406
1407         struct env_image_single *single;
1408         struct env_image_redundant *redundant;
1409
1410         if (!opts)
1411                 opts = &default_opts;
1412
1413         if (parse_config(opts)) /* should fill envdevices */
1414                 return -EINVAL;
1415
1416         addr0 = calloc(1, CUR_ENVSIZE);
1417         if (addr0 == NULL) {
1418                 fprintf(stderr,
1419                         "Not enough memory for environment (%ld bytes)\n",
1420                         CUR_ENVSIZE);
1421                 ret = -ENOMEM;
1422                 goto open_cleanup;
1423         }
1424
1425         /* read environment from FLASH to local buffer */
1426         environment.image = addr0;
1427
1428         if (have_redund_env) {
1429                 redundant = addr0;
1430                 environment.crc = &redundant->crc;
1431                 environment.flags = &redundant->flags;
1432                 environment.data = redundant->data;
1433         } else {
1434                 single = addr0;
1435                 environment.crc = &single->crc;
1436                 environment.flags = NULL;
1437                 environment.data = single->data;
1438         }
1439
1440         dev_current = 0;
1441         if (flash_io(O_RDONLY)) {
1442                 ret = -EIO;
1443                 goto open_cleanup;
1444         }
1445
1446         crc0 = crc32(0, (uint8_t *)environment.data, ENV_SIZE);
1447
1448         crc0_ok = (crc0 == *environment.crc);
1449         if (!have_redund_env) {
1450                 if (!crc0_ok) {
1451                         fprintf(stderr,
1452                                 "Warning: Bad CRC, using default environment\n");
1453                         memcpy(environment.data, default_environment,
1454                                sizeof(default_environment));
1455                         environment.dirty = 1;
1456                 }
1457         } else {
1458                 flag0 = *environment.flags;
1459
1460                 dev_current = 1;
1461                 addr1 = calloc(1, CUR_ENVSIZE);
1462                 if (addr1 == NULL) {
1463                         fprintf(stderr,
1464                                 "Not enough memory for environment (%ld bytes)\n",
1465                                 CUR_ENVSIZE);
1466                         ret = -ENOMEM;
1467                         goto open_cleanup;
1468                 }
1469                 redundant = addr1;
1470
1471                 /*
1472                  * have to set environment.image for flash_read(), careful -
1473                  * other pointers in environment still point inside addr0
1474                  */
1475                 environment.image = addr1;
1476                 if (flash_io(O_RDONLY)) {
1477                         ret = -EIO;
1478                         goto open_cleanup;
1479                 }
1480
1481                 /* Check flag scheme compatibility */
1482                 if (DEVTYPE(dev_current) == MTD_NORFLASH &&
1483                     DEVTYPE(!dev_current) == MTD_NORFLASH) {
1484                         environment.flag_scheme = FLAG_BOOLEAN;
1485                 } else if (DEVTYPE(dev_current) == MTD_NANDFLASH &&
1486                            DEVTYPE(!dev_current) == MTD_NANDFLASH) {
1487                         environment.flag_scheme = FLAG_INCREMENTAL;
1488                 } else if (DEVTYPE(dev_current) == MTD_DATAFLASH &&
1489                            DEVTYPE(!dev_current) == MTD_DATAFLASH) {
1490                         environment.flag_scheme = FLAG_BOOLEAN;
1491                 } else if (DEVTYPE(dev_current) == MTD_UBIVOLUME &&
1492                            DEVTYPE(!dev_current) == MTD_UBIVOLUME) {
1493                         environment.flag_scheme = FLAG_INCREMENTAL;
1494                 } else if (DEVTYPE(dev_current) == MTD_ABSENT &&
1495                            DEVTYPE(!dev_current) == MTD_ABSENT &&
1496                            IS_UBI(dev_current) == IS_UBI(!dev_current)) {
1497                         environment.flag_scheme = FLAG_INCREMENTAL;
1498                 } else {
1499                         fprintf(stderr, "Incompatible flash types!\n");
1500                         ret = -EINVAL;
1501                         goto open_cleanup;
1502                 }
1503
1504                 crc1 = crc32(0, (uint8_t *)redundant->data, ENV_SIZE);
1505
1506                 crc1_ok = (crc1 == redundant->crc);
1507                 flag1 = redundant->flags;
1508
1509                 /*
1510                  * environment.data still points to ((struct
1511                  * env_image_redundant *)addr0)->data. If the two
1512                  * environments differ, or one has bad crc, force a
1513                  * write-out by marking the environment dirty.
1514                  */
1515                 if (memcmp(environment.data, redundant->data, ENV_SIZE) ||
1516                     !crc0_ok || !crc1_ok)
1517                         environment.dirty = 1;
1518
1519                 if (crc0_ok && !crc1_ok) {
1520                         dev_current = 0;
1521                 } else if (!crc0_ok && crc1_ok) {
1522                         dev_current = 1;
1523                 } else if (!crc0_ok && !crc1_ok) {
1524                         fprintf(stderr,
1525                                 "Warning: Bad CRC, using default environment\n");
1526                         memcpy(environment.data, default_environment,
1527                                sizeof(default_environment));
1528                         environment.dirty = 1;
1529                         dev_current = 0;
1530                 } else {
1531                         switch (environment.flag_scheme) {
1532                         case FLAG_BOOLEAN:
1533                                 if (flag0 == ENV_REDUND_ACTIVE &&
1534                                     flag1 == ENV_REDUND_OBSOLETE) {
1535                                         dev_current = 0;
1536                                 } else if (flag0 == ENV_REDUND_OBSOLETE &&
1537                                            flag1 == ENV_REDUND_ACTIVE) {
1538                                         dev_current = 1;
1539                                 } else if (flag0 == flag1) {
1540                                         dev_current = 0;
1541                                 } else if (flag0 == 0xFF) {
1542                                         dev_current = 0;
1543                                 } else if (flag1 == 0xFF) {
1544                                         dev_current = 1;
1545                                 } else {
1546                                         dev_current = 0;
1547                                 }
1548                                 break;
1549                         case FLAG_INCREMENTAL:
1550                                 if (flag0 == 255 && flag1 == 0)
1551                                         dev_current = 1;
1552                                 else if ((flag1 == 255 && flag0 == 0) ||
1553                                          flag0 >= flag1)
1554                                         dev_current = 0;
1555                                 else    /* flag1 > flag0 */
1556                                         dev_current = 1;
1557                                 break;
1558                         default:
1559                                 fprintf(stderr, "Unknown flag scheme %u\n",
1560                                         environment.flag_scheme);
1561                                 return -1;
1562                         }
1563                 }
1564
1565                 /*
1566                  * If we are reading, we don't need the flag and the CRC any
1567                  * more, if we are writing, we will re-calculate CRC and update
1568                  * flags before writing out
1569                  */
1570                 if (dev_current) {
1571                         environment.image = addr1;
1572                         environment.crc = &redundant->crc;
1573                         environment.flags = &redundant->flags;
1574                         environment.data = redundant->data;
1575                         free(addr0);
1576                 } else {
1577                         environment.image = addr0;
1578                         /* Other pointers are already set */
1579                         free(addr1);
1580                 }
1581 #ifdef DEBUG
1582                 fprintf(stderr, "Selected env in %s\n", DEVNAME(dev_current));
1583 #endif
1584         }
1585         return 0;
1586
1587  open_cleanup:
1588         if (addr0)
1589                 free(addr0);
1590
1591         if (addr1)
1592                 free(addr1);
1593
1594         return ret;
1595 }
1596
1597 /*
1598  * Simply free allocated buffer with environment
1599  */
1600 int fw_env_close(struct env_opts *opts)
1601 {
1602         if (environment.image)
1603                 free(environment.image);
1604
1605         environment.image = NULL;
1606
1607         return 0;
1608 }
1609
1610 static int check_device_config(int dev)
1611 {
1612         struct stat st;
1613         int32_t lnum = 0;
1614         int fd, rc = 0;
1615
1616         /* Fills in IS_UBI(), converts DEVNAME() with ubi volume name */
1617         ubi_check_dev(dev);
1618
1619         fd = open(DEVNAME(dev), O_RDONLY);
1620         if (fd < 0) {
1621                 fprintf(stderr,
1622                         "Cannot open %s: %s\n", DEVNAME(dev), strerror(errno));
1623                 return -1;
1624         }
1625
1626         rc = fstat(fd, &st);
1627         if (rc < 0) {
1628                 fprintf(stderr, "Cannot stat the file %s\n", DEVNAME(dev));
1629                 goto err;
1630         }
1631
1632         if (IS_UBI(dev)) {
1633                 rc = ioctl(fd, UBI_IOCEBISMAP, &lnum);
1634                 if (rc < 0) {
1635                         fprintf(stderr, "Cannot get UBI information for %s\n",
1636                                 DEVNAME(dev));
1637                         goto err;
1638                 }
1639         } else if (S_ISCHR(st.st_mode)) {
1640                 struct mtd_info_user mtdinfo;
1641                 rc = ioctl(fd, MEMGETINFO, &mtdinfo);
1642                 if (rc < 0) {
1643                         fprintf(stderr, "Cannot get MTD information for %s\n",
1644                                 DEVNAME(dev));
1645                         goto err;
1646                 }
1647                 if (mtdinfo.type != MTD_NORFLASH &&
1648                     mtdinfo.type != MTD_NANDFLASH &&
1649                     mtdinfo.type != MTD_DATAFLASH &&
1650                     mtdinfo.type != MTD_UBIVOLUME) {
1651                         fprintf(stderr, "Unsupported flash type %u on %s\n",
1652                                 mtdinfo.type, DEVNAME(dev));
1653                         goto err;
1654                 }
1655                 DEVTYPE(dev) = mtdinfo.type;
1656                 if (DEVESIZE(dev) == 0 && ENVSECTORS(dev) == 0 &&
1657                     mtdinfo.type == MTD_NORFLASH)
1658                         DEVESIZE(dev) = mtdinfo.erasesize;
1659                 if (DEVESIZE(dev) == 0)
1660                         /* Assume the erase size is the same as the env-size */
1661                         DEVESIZE(dev) = ENVSIZE(dev);
1662         } else {
1663                 uint64_t size;
1664                 DEVTYPE(dev) = MTD_ABSENT;
1665                 if (DEVESIZE(dev) == 0)
1666                         /* Assume the erase size to be 512 bytes */
1667                         DEVESIZE(dev) = 0x200;
1668
1669                 /*
1670                  * Check for negative offsets, treat it as backwards offset
1671                  * from the end of the block device
1672                  */
1673                 if (DEVOFFSET(dev) < 0) {
1674                         rc = ioctl(fd, BLKGETSIZE64, &size);
1675                         if (rc < 0) {
1676                                 fprintf(stderr,
1677                                         "Could not get block device size on %s\n",
1678                                         DEVNAME(dev));
1679                                 goto err;
1680                         }
1681
1682                         DEVOFFSET(dev) = DEVOFFSET(dev) + size;
1683 #ifdef DEBUG
1684                         fprintf(stderr,
1685                                 "Calculated device offset 0x%llx on %s\n",
1686                                 DEVOFFSET(dev), DEVNAME(dev));
1687 #endif
1688                 }
1689         }
1690
1691         if (ENVSECTORS(dev) == 0)
1692                 /* Assume enough sectors to cover the environment */
1693                 ENVSECTORS(dev) = DIV_ROUND_UP(ENVSIZE(dev), DEVESIZE(dev));
1694
1695         if (DEVOFFSET(dev) % DEVESIZE(dev) != 0) {
1696                 fprintf(stderr,
1697                         "Environment does not start on (erase) block boundary\n");
1698                 errno = EINVAL;
1699                 return -1;
1700         }
1701
1702         if (ENVSIZE(dev) > ENVSECTORS(dev) * DEVESIZE(dev)) {
1703                 fprintf(stderr,
1704                         "Environment does not fit into available sectors\n");
1705                 errno = EINVAL;
1706                 return -1;
1707         }
1708
1709  err:
1710         close(fd);
1711         return rc;
1712 }
1713
1714 static int parse_config(struct env_opts *opts)
1715 {
1716         int rc;
1717
1718         if (!opts)
1719                 opts = &default_opts;
1720
1721 #if defined(CONFIG_FILE)
1722         /* Fills in DEVNAME(), ENVSIZE(), DEVESIZE(). Or don't. */
1723         if (get_config(opts->config_file)) {
1724                 fprintf(stderr, "Cannot parse config file '%s': %m\n",
1725                         opts->config_file);
1726                 return -1;
1727         }
1728 #else
1729         DEVNAME(0) = DEVICE1_NAME;
1730         DEVOFFSET(0) = DEVICE1_OFFSET;
1731         ENVSIZE(0) = ENV1_SIZE;
1732
1733         /* Set defaults for DEVESIZE, ENVSECTORS later once we
1734          * know DEVTYPE
1735          */
1736 #ifdef DEVICE1_ESIZE
1737         DEVESIZE(0) = DEVICE1_ESIZE;
1738 #endif
1739 #ifdef DEVICE1_ENVSECTORS
1740         ENVSECTORS(0) = DEVICE1_ENVSECTORS;
1741 #endif
1742
1743 #ifdef HAVE_REDUND
1744         DEVNAME(1) = DEVICE2_NAME;
1745         DEVOFFSET(1) = DEVICE2_OFFSET;
1746         ENVSIZE(1) = ENV2_SIZE;
1747
1748         /* Set defaults for DEVESIZE, ENVSECTORS later once we
1749          * know DEVTYPE
1750          */
1751 #ifdef DEVICE2_ESIZE
1752         DEVESIZE(1) = DEVICE2_ESIZE;
1753 #endif
1754 #ifdef DEVICE2_ENVSECTORS
1755         ENVSECTORS(1) = DEVICE2_ENVSECTORS;
1756 #endif
1757         have_redund_env = 1;
1758 #endif
1759 #endif
1760         rc = check_device_config(0);
1761         if (rc < 0)
1762                 return rc;
1763
1764         if (have_redund_env) {
1765                 rc = check_device_config(1);
1766                 if (rc < 0)
1767                         return rc;
1768
1769                 if (ENVSIZE(0) != ENVSIZE(1)) {
1770                         fprintf(stderr,
1771                                 "Redundant environments have unequal size\n");
1772                         return -1;
1773                 }
1774         }
1775
1776         usable_envsize = CUR_ENVSIZE - sizeof(uint32_t);
1777         if (have_redund_env)
1778                 usable_envsize -= sizeof(char);
1779
1780         return 0;
1781 }
1782
1783 #if defined(CONFIG_FILE)
1784 static int get_config(char *fname)
1785 {
1786         FILE *fp;
1787         int i = 0;
1788         int rc;
1789         char *line = NULL;
1790         size_t linesize = 0;
1791         char *devname;
1792
1793         fp = fopen(fname, "r");
1794         if (fp == NULL)
1795                 return -1;
1796
1797         while (i < 2 && getline(&line, &linesize, fp) != -1) {
1798                 /* Skip comment strings */
1799                 if (line[0] == '#')
1800                         continue;
1801
1802                 rc = sscanf(line, "%ms %lli %lx %lx %lx",
1803                             &devname,
1804                             &DEVOFFSET(i),
1805                             &ENVSIZE(i), &DEVESIZE(i), &ENVSECTORS(i));
1806
1807                 if (rc < 3)
1808                         continue;
1809
1810                 DEVNAME(i) = devname;
1811
1812                 /* Set defaults for DEVESIZE, ENVSECTORS later once we
1813                  * know DEVTYPE
1814                  */
1815
1816                 i++;
1817         }
1818         free(line);
1819         fclose(fp);
1820
1821         have_redund_env = i - 1;
1822         if (!i) {               /* No valid entries found */
1823                 errno = EINVAL;
1824                 return -1;
1825         } else
1826                 return 0;
1827 }
1828 #endif