commit 2fc80df49f9aaff48c4be10b049df2c3f5e1912e
author Fabio Utzig <utzig@apache.org> Fri Dec 14 06:47:38 2018 -0200
committer Fabio Utzig <utzig@utzig.org> Mon Dec 17 14:41:02 2018 -0200
tree 7d0bcc84f584f2d6e21c567ba0008ca867fa48cd
parent e5831f6ed2914e347b7a7a109eab993d3add56fa

Fix handling of encrypted images

Encrypted images were known to be failing when the header size was larger
than 256 bytes because of incorrect handling of blocks sent to decryption
and hashing routines. An assert was previously added to check the header
and read block sizes matched to avoid incurring into the know error, but
it was incorrectly enabled also for non-encrypted images.

Now the handling of the header, which is not encrypted, is correctly
separated from the handling of the remaining image, when encryption is
used, to avoid ever sending header data into the decryption routines.

Signed-off-by: Fabio Utzig <utzig@apache.org>

boot/bootutil/src/loader.c

diff --git a/boot/bootutil/src/loader.c b/boot/bootutil/src/loader.c
index 6839ddf..3b21b79 100644
--- a/boot/bootutil/src/loader.c
+++ b/boot/bootutil/src/loader.c
@@ -586,7 +586,7 @@
     (void)bs;
     (void)rc;
 #else
-    if (fap->fa_id == FLASH_AREA_IMAGE_1 && hdr->ih_flags & IMAGE_F_ENCRYPTED) {
+    if (fap->fa_id == FLASH_AREA_IMAGE_1 && IS_ENCRYPTED(hdr)) {
         rc = boot_enc_load(hdr, fap, bs->enckey[1]);
         if (rc < 0) {
             return BOOT_EBADIMAGE;
@@ -821,7 +821,7 @@
                 hdr = boot_img_hdr(&boot_data, 0);
                 off = off_dst;
             }
-            if (hdr->ih_flags & IMAGE_F_ENCRYPTED) {
+            if (IS_ENCRYPTED(hdr)) {
                 blk_sz = chunk_sz;
                 idx = 0;
                 if (off + bytes_copied < hdr->ih_hdr_size) {
@@ -1136,7 +1136,7 @@
     }
 
 #ifdef MCUBOOT_ENC_IMAGES
-    if (boot_img_hdr(&boot_data, 1)->ih_flags & IMAGE_F_ENCRYPTED) {
+    if (IS_ENCRYPTED(boot_img_hdr(&boot_data, 1))) {
         rc = boot_enc_load(boot_img_hdr(&boot_data, 1), fap_slot1, bs->enckey[1]);
         if (rc < 0) {
             return BOOT_EBADIMAGE;
@@ -1220,7 +1220,7 @@
         }
 
 #ifdef MCUBOOT_ENC_IMAGES
-        if (hdr->ih_flags & IMAGE_F_ENCRYPTED) {
+        if (IS_ENCRYPTED(hdr)) {
             fap = BOOT_IMG_AREA(&boot_data, 0);
             rc = boot_enc_load(hdr, fap, bs->enckey[0]);
             assert(rc >= 0);
@@ -1244,7 +1244,7 @@
 
 #ifdef MCUBOOT_ENC_IMAGES
         hdr = boot_img_hdr(&boot_data, 1);
-        if (hdr->ih_flags & IMAGE_F_ENCRYPTED) {
+        if (IS_ENCRYPTED(hdr)) {
             fap = BOOT_IMG_AREA(&boot_data, 1);
             rc = boot_enc_load(hdr, fap, bs->enckey[1]);
             assert(rc >= 0);