image encryption: fix enc_state array indexing for zephyr
enc_state table was indexed with assumption that
image flash area are subsequent and increasing numbers.
It might not be true while building zephyr.
Patch introduce flash_area_id_to_image_slot() implementation for
the zephyr port and uses it to assign proper slot number.
This API is already available in MyNewt.
Signed-off-by: Andrzej Puzdrowski <andrzej.puzdrowski@nordicsemi.no>
diff --git a/boot/bootutil/src/encrypted.c b/boot/bootutil/src/encrypted.c
index 14cbcd5..13ba2f4 100644
--- a/boot/bootutil/src/encrypted.c
+++ b/boot/bootutil/src/encrypted.c
@@ -233,7 +233,11 @@
uint8_t enckey_type;
int rc;
- slot = fap->fa_id - FLASH_AREA_IMAGE_PRIMARY;
+ rc = flash_area_id_to_image_slot(fap->fa_id);
+ if (rc < 0) {
+ return rc;
+ }
+ slot = rc;
/* Already loaded... */
if (enc_state[slot].valid) {
@@ -305,7 +309,16 @@
int
boot_enc_valid(const struct flash_area *fap)
{
- return enc_state[fap->fa_id - FLASH_AREA_IMAGE_PRIMARY].valid;
+ int rc;
+
+ rc = flash_area_id_to_image_slot(fap->fa_id);
+ if (rc < 0) {
+ /* can't get proper slot number - skip encryption, */
+ /* postpone the erro for a upper layer */
+ return 0;
+ }
+
+ return enc_state[rc].valid;
}
void
@@ -317,6 +330,7 @@
uint8_t u8;
uint8_t nonce[16];
uint8_t blk[16];
+ int rc;
memset(nonce, 0, 12);
off >>= 4;
@@ -325,7 +339,13 @@
nonce[14] = (uint8_t)(off >> 8);
nonce[15] = (uint8_t)off;
- enc = &enc_state[fap->fa_id - FLASH_AREA_IMAGE_PRIMARY];
+ rc = flash_area_id_to_image_slot(fap->fa_id);
+ if (rc < 0) {
+ assert(0);
+ return;
+ }
+
+ enc = &enc_state[rc];
assert(enc->valid == 1);
for (i = 0; i < sz; i++) {
if (i == 0 || blk_off == 0) {
diff --git a/boot/zephyr/flash_map_extended.c b/boot/zephyr/flash_map_extended.c
index 1b1b5ad..543a467 100644
--- a/boot/zephyr/flash_map_extended.c
+++ b/boot/zephyr/flash_map_extended.c
@@ -66,6 +66,19 @@
return -EINVAL; /* flash_area_open will fail on that */
}
+int flash_area_id_to_image_slot(int area_id)
+{
+ switch (area_id) {
+ case FLASH_AREA_IMAGE_PRIMARY:
+ return 0;
+ case FLASH_AREA_IMAGE_SECONDARY:
+ return 1;
+ default:
+ BOOT_LOG_ERR("invalid flash area ID");
+ return -1;
+ }
+}
+
int flash_area_sector_from_off(off_t off, struct flash_sector *sector)
{
int rc;
diff --git a/boot/zephyr/include/flash_map_backend/flash_map_backend.h b/boot/zephyr/include/flash_map_backend/flash_map_backend.h
index 178c34f..c082dd6 100644
--- a/boot/zephyr/include/flash_map_backend/flash_map_backend.h
+++ b/boot/zephyr/include/flash_map_backend/flash_map_backend.h
@@ -52,6 +52,14 @@
int flash_area_id_from_image_slot(int slot);
+/**
+ * Converts the specified flash area ID to an image slot index.
+ *
+ * Returns image slot index (0 or 1), or -1 if ID doesn't correspond to an image
+ * slot.
+ */
+int flash_area_id_to_image_slot(int area_id);
+
/* Retrieve the flash sector a given offset belongs to.
*
* Returns 0 on success, or an error code on failure.
diff --git a/sim/mcuboot-sys/csupport/run.c b/sim/mcuboot-sys/csupport/run.c
index eb5b155..fdee14c 100644
--- a/sim/mcuboot-sys/csupport/run.c
+++ b/sim/mcuboot-sys/csupport/run.c
@@ -384,6 +384,19 @@
return 0;
}
+int flash_area_id_to_image_slot(int area_id)
+{
+ switch (area_id) {
+ case FLASH_AREA_IMAGE_PRIMARY:
+ return 0;
+ case FLASH_AREA_IMAGE_SECONDARY:
+ return 1;
+ default:
+ printf("Unsupported image area ID\n");
+ abort();
+ }
+}
+
void sim_assert(int x, const char *assertion, const char *file, unsigned int line, const char *function)
{
if (!(x)) {