git.ozlabs.org Git - petitboot/blob - lib/flash/flash.c

   1 /*
   2  *  Copyright (C) 2015 IBM Corporation
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; version 2 of the License.
   7  *
   8  *  This program is distributed in the hope that it will be useful,
   9  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  *  GNU General Public License for more details.
  12  *
  13  */
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <unistd.h>
  18 #include <getopt.h>
  19 #include <errno.h>
  20 #include <asm/byteorder.h>
  21
  22 #include <log/log.h>
  23 #include <talloc/talloc.h>
  24 #include <flash/flash.h>
  25 #include <ccan/endian/endian.h>
  26
  27 #include <libflash/arch_flash.h>
  28 #include <libflash/blocklevel.h>
  29 #include <libflash/libflash.h>
  30 #include <libflash/libffs.h>
  31 #include <libflash/file.h>
  32 #include <libflash/ecc.h>
  33
  34 #define SECURE_BOOT_HEADERS_SIZE 4096
  35 #define ROM_MAGIC_NUMBER 0x17082011
  36
  37 struct flash_info {
  38         /* Device information */
  39         struct blocklevel_device        *bl;
  40         struct ffs_handle               *ffs;
  41         uint64_t                        size;   /* raw size of partition */
  42         const char                      *path;
  43         bool                            ecc;
  44         uint32_t                        erase_granule;
  45
  46         /* Partition information */
  47         uint32_t                        attr_part_idx;
  48         uint32_t                        attr_data_pos;
  49         uint32_t                        attr_data_len; /* Includes ECC bytes */
  50
  51         /* 'Other Side' info if present */
  52         struct flash_info               *other_side;
  53
  54 };
  55
  56 static int partition_info(struct flash_info *info, const char *partition)
  57 {
  58         int rc;
  59
  60         rc = ffs_lookup_part(info->ffs, partition, &info->attr_part_idx);
  61         if (rc) {
  62                 pb_log("Failed to find %s partition\n", partition);
  63                 return rc;
  64         }
  65
  66         return ffs_part_info(info->ffs, info->attr_part_idx, NULL,
  67                            &info->attr_data_pos, &info->attr_data_len,
  68                            NULL, &info->ecc);
  69 }
  70
  71 static struct flash_info *flash_setup_buffer(void *ctx, const char *partition)
  72 {
  73         struct flash_info *info;
  74         struct ffs_handle *tmp = NULL;
  75         int rc = 0;
  76
  77         if (!partition)
  78                 return NULL;
  79
  80         info = talloc_zero(ctx, struct flash_info);
  81         if (!info)
  82                 return NULL;
  83
  84         rc = arch_flash_init(&info->bl, NULL, true);
  85         if (rc) {
  86                 pb_log("Failed to init mtd device\n");
  87                 goto out;
  88         }
  89
  90         rc = blocklevel_get_info(info->bl, &info->path, &info->size,
  91                                  &info->erase_granule);
  92         if (rc) {
  93                 pb_log("Failed to retrieve blocklevel info\n");
  94                 goto out_flash;
  95         }
  96
  97         rc = ffs_init(0, info->size, info->bl, &info->ffs, 1);
  98         if (rc) {
  99                 pb_log_fn("Failed to init ffs\n");
 100                 goto out_flash;
 101         }
 102
 103         rc = partition_info(info, partition);
 104         if (rc) {
 105                 pb_log("Failed to retrieve partition info\n");
 106                 goto out_ffs;
 107         }
 108
 109         /* Check if there is a second flash side. If there is not, or
 110          * we fail to recognise it, ignore it and continue */
 111         ffs_next_side(info->ffs, &tmp, info->ecc);
 112         if (tmp && ffs_equal(info->ffs, tmp) == false) {
 113                 pb_debug("Other side present on MTD device\n");
 114                 info->other_side = talloc_zero(info, struct flash_info);
 115                 info->other_side->ffs = tmp;
 116                 info->other_side->bl = info->bl;
 117                 info->other_side->size = info->size;
 118                 info->other_side->path = info->path;
 119                 info->other_side->ecc = info->ecc;
 120                 info->other_side->erase_granule = info->erase_granule;
 121                 rc = partition_info(info->other_side, partition);
 122                 if (rc)
 123                         pb_log("Failed to retrieve partition info "
 124                                "for other side - ignoring\n");
 125         }
 126
 127         pb_debug("%s Details\n", partition);
 128         pb_debug("\tName\t\t%s\n", info->path);
 129         pb_debug("\tFlash Size\t%lu\n", info->size);
 130         pb_debug("\tGranule\t\t%u\n", info->erase_granule);
 131         pb_debug("\tECC\t\t%s\n", info->ecc ? "Protected" : "Unprotected");
 132         pb_debug("\tCurrent Side info:\n");
 133         pb_debug("\tIndex\t\t%u\n", info->attr_part_idx);
 134         pb_debug("\tOffset\t\t%u\n", info->attr_data_pos);
 135         pb_debug("\tPart. Size\t%u\n", info->attr_data_len);
 136         if (info->other_side) {
 137                 pb_debug("\tOther Side info:\n");
 138                 pb_debug("\tIndex\t\t%u\n", info->other_side->attr_part_idx);
 139                 pb_debug("\tOffset\t\t%u\n", info->other_side->attr_data_pos);
 140                 pb_debug("\tPart. Size\t%u\n", info->other_side->attr_data_len);
 141         }
 142
 143         return info;
 144 out_ffs:
 145         ffs_close(info->ffs);
 146 out_flash:
 147         arch_flash_close(info->bl, NULL);
 148 out:
 149         talloc_free(info);
 150         return NULL;
 151 }
 152
 153 /* See stb_is_container() in Skiboot */
 154 static bool is_signed(char *buffer, uint32_t len)
 155 {
 156         if (!buffer || len <= SECURE_BOOT_HEADERS_SIZE)
 157                 return false;
 158         if (be32_to_cpu(*(uint32_t *)buffer) != ROM_MAGIC_NUMBER)
 159                 return false;
 160         return true;
 161 }
 162
 163 int flash_parse_version(void *ctx, char ***versions, bool current)
 164 {
 165         char *saveptr, *tok,  **tmp, *buffer;
 166         const char *delim = "\n";
 167         struct flash_info *info, *cur_info;
 168         uint32_t len;
 169         int rc, n = 0;
 170
 171         saveptr = tok = NULL;
 172         tmp = NULL;
 173
 174         info = flash_setup_buffer(ctx, "VERSION");
 175         if (!info)
 176                 return 0;
 177
 178         if (!current && !info->other_side)
 179                 return 0;
 180
 181         cur_info = !current ? info->other_side : info;
 182
 183         len = cur_info->attr_data_len -  ecc_size(cur_info->attr_data_len);
 184         buffer = talloc_array(cur_info, char, len);
 185         if (!buffer) {
 186                 pb_log_fn("Failed to init buffer!\n");
 187                 goto out;
 188         }
 189
 190         rc = blocklevel_read(cur_info->bl, cur_info->attr_data_pos,
 191                              buffer, len);
 192         if (rc) {
 193                 pb_log("Failed to read VERSION partition\n");
 194                 goto out;
 195         }
 196
 197         /* Check if this partition is signed */
 198         if (is_signed(buffer, len))
 199                 buffer += SECURE_BOOT_HEADERS_SIZE;
 200
 201         /* open-power-platform */
 202         tok = strtok_r(buffer, delim, &saveptr);
 203         if (tok) {
 204                 tmp = talloc_realloc(ctx, tmp, char *, n + 1);
 205                 if (!tmp) {
 206                         pb_log_fn("Failed to allocate memory\n");
 207                         goto out;
 208                 }
 209                 tmp[n++] = talloc_strdup(ctx, tok);
 210         }
 211
 212         tok = strtok_r(NULL, delim, &saveptr);
 213         while (tok) {
 214                 /* Ignore leading tab from subsequent lines */
 215                 tmp = talloc_realloc(ctx, tmp, char *, n + 1);
 216                 if (!tmp) {
 217                         pb_log_fn("Failed to reallocate memory\n");
 218                         n = 0;
 219                         goto out;
 220                 }
 221                 tmp[n++] = talloc_strdup(ctx, tok + 1);
 222                 tok = strtok_r(NULL, delim, &saveptr);
 223         }
 224
 225 out:
 226         pb_debug("%d version strings read from %s side\n",
 227                  n, current ? "current" : "other");
 228         arch_flash_close(info->bl, NULL);
 229         talloc_free(info);
 230         *versions = tmp;
 231         return n;
 232 }