util/smmstoretool/storage.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 #include "storage.h"
   4
   5 #include <assert.h>
   6 #include <stdio.h>
   7
   8 #include "commonlib/bsd/compiler.h"
   9 #include "fmap.h"
  10
  11 #include "fv.h"
  12 #include "utils.h"
  13
  14 bool storage_open(const char store_file[], struct storage_t *storage, bool rw)
  15 {
  16         storage->rw = rw;
  17
  18         storage->file = map_file(store_file, rw);
  19         if (storage->file.start == NULL) {
  20                 fprintf(stderr, "Failed to load smm-store-file \"%s\"\n",
  21                         store_file);
  22                 return false;
  23         }
  24
  25         /* If we won't find FMAP with SMMSTORE, use the whole file, but fail if
  26          * FMAP is there without SMMSTORE. */
  27         storage->region = storage->file;
  28
  29         long fmap_offset = fmap_find(storage->file.start, storage->file.length);
  30         if (fmap_offset >= 0) {
  31                 struct fmap *fmap = (void *)(storage->file.start + fmap_offset);
  32                 const struct fmap_area *area = fmap_find_area(fmap, "SMMSTORE");
  33                 if (area == NULL) {
  34                         fprintf(stderr,
  35                                 "Found FMAP without SMMSTORE in \"%s\"\n",
  36                                 store_file);
  37                         return false;
  38                 }
  39
  40                 storage->region.start += area->offset;
  41                 storage->region.length = area->size;
  42         }
  43
  44         bool auth_vars;
  45         if (!fv_parse(storage->region, &storage->store_area, &auth_vars)) {
  46                 if (!rw) {
  47                         fprintf(stderr,
  48                                 "Failed to find variable store in \"%s\"\n",
  49                                 store_file);
  50                         goto error;
  51                 }
  52
  53                 fprintf(stderr,
  54                         "\nThe variable store has not been found in the ROM image\n"
  55                         "and is about to be initialized. This situation is normal\n"
  56                         "for a release image, as the variable store is usually\n"
  57                         "initialized on the first boot of the platform.\n\n");
  58
  59                 if (!fv_init(storage->region)) {
  60                         fprintf(stderr,
  61                                 "Failed to create variable store in \"%s\"\n",
  62                                 store_file);
  63                         goto error;
  64                 }
  65
  66                 if (!fv_parse(storage->region, &storage->store_area, &auth_vars)) {
  67                         fprintf(stderr,
  68                                 "Failed to parse newly formatted store in \"%s\"\n",
  69                                 store_file);
  70                         goto error;
  71                 }
  72
  73                 fprintf(stderr,
  74                         "Successfully created variable store in \"%s\"\n",
  75                         store_file);
  76         }
  77
  78         storage->vs = vs_load(storage->store_area, auth_vars);
  79         return true;
  80
  81 error:
  82         unmap_file(storage->file);
  83         return false;
  84 }
  85
  86 bool storage_write_back(struct storage_t *storage)
  87 {
  88         assert(storage->rw && "Only RW storage can be updated.");
  89
  90         bool success = vs_store(&storage->vs, storage->store_area);
  91         if (!success)
  92                 fprintf(stderr, "Failed to update variable store\n");
  93         storage_drop(storage);
  94         return success;
  95 }
  96
  97 void storage_drop(struct storage_t *storage)
  98 {
  99         unmap_file(storage->file);
 100         vs_free(&storage->vs);
 101 }