common/cmd_gpt.c

   1 /*
   2  * cmd_gpt.c -- GPT (GUID Partition Table) handling command
   3  *
   4  * Copyright (C) 2012 Samsung Electronics
   5  * author: Lukasz Majewski <l.majewski@samsung.com>
   6  * author: Piotr Wilczek <p.wilczek@samsung.com>
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #include <common.h>
  12 #include <malloc.h>
  13 #include <command.h>
  14 #include <part_efi.h>
  15 #include <exports.h>
  16 #include <linux/ctype.h>
  17 #include <div64.h>
  18
  19 #ifndef CONFIG_PARTITION_UUIDS
  20 #error CONFIG_PARTITION_UUIDS must be enabled for CONFIG_CMD_GPT to be enabled
  21 #endif
  22
  23 /**
  24  * extract_env(): Expand env name from string format '&{env_name}'
  25  *                and return pointer to the env (if the env is set)
  26  *
  27  * @param str - pointer to string
  28  * @param env - pointer to pointer to extracted env
  29  *
  30  * @return - zero on successful expand and env is set
  31  */
  32 static int extract_env(const char *str, char **env)
  33 {
  34         int ret = -1;
  35         char *e, *s;
  36 #ifdef CONFIG_RANDOM_UUID
  37         char uuid_str[UUID_STR_LEN + 1];
  38 #endif
  39
  40         if (!str || strlen(str) < 4)
  41                 return -1;
  42
  43         if (!((strncmp(str, "${", 2) == 0) && (str[strlen(str) - 1] == '}')))
  44                 return -1;
  45
  46         s = strdup(str);
  47         if (s == NULL)
  48                 return -1;
  49
  50         memset(s + strlen(s) - 1, '\0', 1);
  51         memmove(s, s + 2, strlen(s) - 1);
  52
  53         e = getenv(s);
  54         if (e == NULL) {
  55 #ifdef CONFIG_RANDOM_UUID
  56                 debug("%s unset. ", str);
  57                 gen_rand_uuid_str(uuid_str, UUID_STR_FORMAT_STD);
  58                 setenv(s, uuid_str);
  59
  60                 e = getenv(s);
  61                 if (e) {
  62                         debug("Set to random.\n");
  63                         ret = 0;
  64                 } else {
  65                         debug("Can't get random UUID.\n");
  66                 }
  67 #else
  68                 debug("%s unset.\n", str);
  69 #endif
  70         } else {
  71                 debug("%s get from environment.\n", str);
  72                 ret = 0;
  73         }
  74
  75         *env = e;
  76         free(s);
  77
  78         return ret;
  79 }
  80
  81 /**
  82  * extract_val(): Extract value from a key=value pair list (comma separated).
  83  *                Only value for the given key is returend.
  84  *                Function allocates memory for the value, remember to free!
  85  *
  86  * @param str - pointer to string with key=values pairs
  87  * @param key - pointer to the key to search for
  88  *
  89  * @return - pointer to allocated string with the value
  90  */
  91 static char *extract_val(const char *str, const char *key)
  92 {
  93         char *v, *k;
  94         char *s, *strcopy;
  95         char *new = NULL;
  96
  97         strcopy = strdup(str);
  98         if (strcopy == NULL)
  99                 return NULL;
 100
 101         s = strcopy;
 102         while (s) {
 103                 v = strsep(&s, ",");
 104                 if (!v)
 105                         break;
 106                 k = strsep(&v, "=");
 107                 if (!k)
 108                         break;
 109                 if  (strcmp(k, key) == 0) {
 110                         new = strdup(v);
 111                         break;
 112                 }
 113         }
 114
 115         free(strcopy);
 116
 117         return new;
 118 }
 119
 120 /**
 121  * set_gpt_info(): Fill partition information from string
 122  *              function allocates memory, remember to free!
 123  *
 124  * @param dev_desc - pointer block device descriptor
 125  * @param str_part - pointer to string with partition information
 126  * @param str_disk_guid - pointer to pointer to allocated string with disk guid
 127  * @param partitions - pointer to pointer to allocated partitions array
 128  * @param parts_count - number of partitions
 129  *
 130  * @return - zero on success, otherwise error
 131  *
 132  */
 133 static int set_gpt_info(block_dev_desc_t *dev_desc,
 134                         const char *str_part,
 135                         char **str_disk_guid,
 136                         disk_partition_t **partitions,
 137                         u8 *parts_count)
 138 {
 139         char *tok, *str, *s;
 140         int i;
 141         char *val, *p;
 142         int p_count;
 143         disk_partition_t *parts;
 144         int errno = 0;
 145         uint64_t size_ll, start_ll;
 146
 147         debug("%s:  lba num: 0x%x %d\n", __func__,
 148               (unsigned int)dev_desc->lba, (unsigned int)dev_desc->lba);
 149
 150         if (str_part == NULL)
 151                 return -1;
 152
 153         str = strdup(str_part);
 154
 155         /* extract disk guid */
 156         s = str;
 157         val = extract_val(str, "uuid_disk");
 158         if (!val) {
 159 #ifdef CONFIG_RANDOM_UUID
 160                 *str_disk_guid = malloc(UUID_STR_LEN + 1);
 161                 gen_rand_uuid_str(*str_disk_guid, UUID_STR_FORMAT_STD);
 162 #else
 163                 free(str);
 164                 return -2;
 165 #endif
 166         } else {
 167                 val = strsep(&val, ";");
 168                 if (extract_env(val, &p))
 169                         p = val;
 170                 *str_disk_guid = strdup(p);
 171                 free(val);
 172                 /* Move s to first partition */
 173                 strsep(&s, ";");
 174         }
 175         if (strlen(s) == 0)
 176                 return -3;
 177
 178         i = strlen(s) - 1;
 179         if (s[i] == ';')
 180                 s[i] = '\0';
 181
 182         /* calculate expected number of partitions */
 183         p_count = 1;
 184         p = s;
 185         while (*p) {
 186                 if (*p++ == ';')
 187                         p_count++;
 188         }
 189
 190         /* allocate memory for partitions */
 191         parts = calloc(sizeof(disk_partition_t), p_count);
 192
 193         /* retrieve partitions data from string */
 194         for (i = 0; i < p_count; i++) {
 195                 tok = strsep(&s, ";");
 196
 197                 if (tok == NULL)
 198                         break;
 199
 200                 /* uuid */
 201                 val = extract_val(tok, "uuid");
 202                 if (!val) {
 203                         /* 'uuid' is optional if random uuid's are enabled */
 204 #ifdef CONFIG_RANDOM_UUID
 205                         gen_rand_uuid_str(parts[i].uuid, UUID_STR_FORMAT_STD);
 206 #else
 207                         errno = -4;
 208                         goto err;
 209 #endif
 210                 } else {
 211                         if (extract_env(val, &p))
 212                                 p = val;
 213                         if (strlen(p) >= sizeof(parts[i].uuid)) {
 214                                 printf("Wrong uuid format for partition %d\n", i);
 215                                 errno = -4;
 216                                 goto err;
 217                         }
 218                         strcpy((char *)parts[i].uuid, p);
 219                         free(val);
 220                 }
 221 #ifdef CONFIG_PARTITION_TYPE_GUID
 222                 /* guid */
 223                 val = extract_val(tok, "type");
 224                 if (val) {
 225                         /* 'type' is optional */
 226                         if (extract_env(val, &p))
 227                                 p = val;
 228                         if (strlen(p) >= sizeof(parts[i].type_guid)) {
 229                                 printf("Wrong type guid format for partition %d\n",
 230                                        i);
 231                                 errno = -4;
 232                                 goto err;
 233                         }
 234                         strcpy((char *)parts[i].type_guid, p);
 235                         free(val);
 236                 }
 237 #endif
 238                 /* name */
 239                 val = extract_val(tok, "name");
 240                 if (!val) { /* name is mandatory */
 241                         errno = -4;
 242                         goto err;
 243                 }
 244                 if (extract_env(val, &p))
 245                         p = val;
 246                 if (strlen(p) >= sizeof(parts[i].name)) {
 247                         errno = -4;
 248                         goto err;
 249                 }
 250                 strcpy((char *)parts[i].name, p);
 251                 free(val);
 252
 253                 /* size */
 254                 val = extract_val(tok, "size");
 255                 if (!val) { /* 'size' is mandatory */
 256                         errno = -4;
 257                         goto err;
 258                 }
 259                 if (extract_env(val, &p))
 260                         p = val;
 261                 size_ll = ustrtoull(p, &p, 0);
 262                 parts[i].size = lldiv(size_ll, dev_desc->blksz);
 263                 free(val);
 264
 265                 /* start address */
 266                 val = extract_val(tok, "start");
 267                 if (val) { /* start address is optional */
 268                         if (extract_env(val, &p))
 269                                 p = val;
 270                         start_ll = ustrtoull(p, &p, 0);
 271                         parts[i].start = lldiv(start_ll, dev_desc->blksz);
 272                         free(val);
 273                 }
 274         }
 275
 276         *parts_count = p_count;
 277         *partitions = parts;
 278         free(str);
 279
 280         return 0;
 281 err:
 282         free(str);
 283         free(*str_disk_guid);
 284         free(parts);
 285
 286         return errno;
 287 }
 288
 289 static int gpt_default(block_dev_desc_t *blk_dev_desc, const char *str_part)
 290 {
 291         int ret;
 292         char *str_disk_guid;
 293         u8 part_count = 0;
 294         disk_partition_t *partitions = NULL;
 295
 296         /* fill partitions */
 297         ret = set_gpt_info(blk_dev_desc, str_part,
 298                         &str_disk_guid, &partitions, &part_count);
 299         if (ret) {
 300                 if (ret == -1)
 301                         printf("No partition list provided\n");
 302                 if (ret == -2)
 303                         printf("Missing disk guid\n");
 304                 if ((ret == -3) || (ret == -4))
 305                         printf("Partition list incomplete\n");
 306                 return -1;
 307         }
 308
 309         /* save partitions layout to disk */
 310         ret = gpt_restore(blk_dev_desc, str_disk_guid, partitions, part_count);
 311         free(str_disk_guid);
 312         free(partitions);
 313
 314         return ret;
 315 }
 316
 317 /**
 318  * do_gpt(): Perform GPT operations
 319  *
 320  * @param cmdtp - command name
 321  * @param flag
 322  * @param argc
 323  * @param argv
 324  *
 325  * @return zero on success; otherwise error
 326  */
 327 static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 328 {
 329         int ret = CMD_RET_SUCCESS;
 330         int dev = 0;
 331         char *ep;
 332         block_dev_desc_t *blk_dev_desc;
 333
 334         if (argc < 5)
 335                 return CMD_RET_USAGE;
 336
 337         /* command: 'write' */
 338         if ((strcmp(argv[1], "write") == 0) && (argc == 5)) {
 339                 dev = (int)simple_strtoul(argv[3], &ep, 10);
 340                 if (!ep || ep[0] != '\0') {
 341                         printf("'%s' is not a number\n", argv[3]);
 342                         return CMD_RET_USAGE;
 343                 }
 344                 blk_dev_desc = get_dev(argv[2], dev);
 345                 if (!blk_dev_desc) {
 346                         printf("%s: %s dev %d NOT available\n",
 347                                __func__, argv[2], dev);
 348                         return CMD_RET_FAILURE;
 349                 }
 350
 351                 puts("Writing GPT: ");
 352
 353                 ret = gpt_default(blk_dev_desc, argv[4]);
 354                 if (!ret) {
 355                         puts("success!\n");
 356                         return CMD_RET_SUCCESS;
 357                 } else {
 358                         puts("error!\n");
 359                         return CMD_RET_FAILURE;
 360                 }
 361         } else {
 362                 return CMD_RET_USAGE;
 363         }
 364         return ret;
 365 }
 366
 367 U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 368         "GUID Partition Table",
 369         "<command> <interface> <dev> <partitions_list>\n"
 370         " - GUID partition table restoration\n"
 371         " Restore GPT information on a device connected\n"
 372         " to interface\n"
 373 );