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