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  }