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         tok = strsep(&s, ";");
 158         val = extract_val(tok, "uuid_disk");
 159         if (!val) {
 160                 free(str);
 161                 return -2;
 162         }
 163         if (extract_env(val, &p))
 164                 p = val;
 165         *str_disk_guid = strdup(p);
 166         free(val);
 167
 168         if (strlen(s) == 0)
 169                 return -3;
 170
 171         i = strlen(s) - 1;
 172         if (s[i] == ';')
 173                 s[i] = '\0';
 174
 175         /* calculate expected number of partitions */
 176         p_count = 1;
 177         p = s;
 178         while (*p) {
 179                 if (*p++ == ';')
 180                         p_count++;
 181         }
 182
 183         /* allocate memory for partitions */
 184         parts = calloc(sizeof(disk_partition_t), p_count);
 185
 186         /* retrieve partitions data from string */
 187         for (i = 0; i < p_count; i++) {
 188                 tok = strsep(&s, ";");
 189
 190                 if (tok == NULL)
 191                         break;
 192
 193                 /* uuid */
 194                 val = extract_val(tok, "uuid");
 195                 if (!val) { /* 'uuid' is mandatory */
 196                         errno = -4;
 197                         goto err;
 198                 }
 199                 if (extract_env(val, &p))
 200                         p = val;
 201                 if (strlen(p) >= sizeof(parts[i].uuid)) {
 202                         printf("Wrong uuid format for partition %d\n", i);
 203                         errno = -4;
 204                         goto err;
 205                 }
 206                 strcpy((char *)parts[i].uuid, p);
 207                 free(val);
 208
 209                 /* name */
 210                 val = extract_val(tok, "name");
 211                 if (!val) { /* name is mandatory */
 212                         errno = -4;
 213                         goto err;
 214                 }
 215                 if (extract_env(val, &p))
 216                         p = val;
 217                 if (strlen(p) >= sizeof(parts[i].name)) {
 218                         errno = -4;
 219                         goto err;
 220                 }
 221                 strcpy((char *)parts[i].name, p);
 222                 free(val);
 223
 224                 /* size */
 225                 val = extract_val(tok, "size");
 226                 if (!val) { /* 'size' is mandatory */
 227                         errno = -4;
 228                         goto err;
 229                 }
 230                 if (extract_env(val, &p))
 231                         p = val;
 232                 size_ll = ustrtoull(p, &p, 0);
 233                 parts[i].size = lldiv(size_ll, dev_desc->blksz);
 234                 free(val);
 235
 236                 /* start address */
 237                 val = extract_val(tok, "start");
 238                 if (val) { /* start address is optional */
 239                         if (extract_env(val, &p))
 240                                 p = val;
 241                         start_ll = ustrtoull(p, &p, 0);
 242                         parts[i].start = lldiv(start_ll, dev_desc->blksz);
 243                         free(val);
 244                 }
 245         }
 246
 247         *parts_count = p_count;
 248         *partitions = parts;
 249         free(str);
 250
 251         return 0;
 252 err:
 253         free(str);
 254         free(*str_disk_guid);
 255         free(parts);
 256
 257         return errno;
 258 }
 259
 260 static int gpt_default(block_dev_desc_t *blk_dev_desc, const char *str_part)
 261 {
 262         int ret;
 263         char *str_disk_guid;
 264         u8 part_count = 0;
 265         disk_partition_t *partitions = NULL;
 266
 267         if (!str_part)
 268                 return -1;
 269
 270         /* fill partitions */
 271         ret = set_gpt_info(blk_dev_desc, str_part,
 272                         &str_disk_guid, &partitions, &part_count);
 273         if (ret) {
 274                 if (ret == -1)
 275                         printf("No partition list provided\n");
 276                 if (ret == -2)
 277                         printf("Missing disk guid\n");
 278                 if ((ret == -3) || (ret == -4))
 279                         printf("Partition list incomplete\n");
 280                 return -1;
 281         }
 282
 283         /* save partitions layout to disk */
 284         gpt_restore(blk_dev_desc, str_disk_guid, partitions, part_count);
 285         free(str_disk_guid);
 286         free(partitions);
 287
 288         return 0;
 289 }
 290
 291 /**
 292  * do_gpt(): Perform GPT operations
 293  *
 294  * @param cmdtp - command name
 295  * @param flag
 296  * @param argc
 297  * @param argv
 298  *
 299  * @return zero on success; otherwise error
 300  */
 301 static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 302 {
 303         int ret = CMD_RET_SUCCESS;
 304         int dev = 0;
 305         char *ep;
 306         block_dev_desc_t *blk_dev_desc;
 307
 308         if (argc < 5)
 309                 return CMD_RET_USAGE;
 310
 311         /* command: 'write' */
 312         if ((strcmp(argv[1], "write") == 0) && (argc == 5)) {
 313                 dev = (int)simple_strtoul(argv[3], &ep, 10);
 314                 if (!ep || ep[0] != '\0') {
 315                         printf("'%s' is not a number\n", argv[3]);
 316                         return CMD_RET_USAGE;
 317                 }
 318                 blk_dev_desc = get_dev(argv[2], dev);
 319                 if (!blk_dev_desc) {
 320                         printf("%s: %s dev %d NOT available\n",
 321                                __func__, argv[2], dev);
 322                         return CMD_RET_FAILURE;
 323                 }
 324
 325                 puts("Writing GPT: ");
 326
 327                 ret = gpt_default(blk_dev_desc, argv[4]);
 328                 if (!ret) {
 329                         puts("success!\n");
 330                         return CMD_RET_SUCCESS;
 331                 } else {
 332                         puts("error!\n");
 333                         return CMD_RET_FAILURE;
 334                 }
 335         } else {
 336                 return CMD_RET_USAGE;
 337         }
 338         return ret;
 339 }
 340
 341 U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 342         "GUID Partition Table",
 343         "<command> <interface> <dev> <partitions_list>\n"
 344         " - GUID partition table restoration\n"
 345         " Restore GPT information on a device connected\n"
 346         " to interface\n"
 347 );