boot: add delta DFU support

.github/workflows/sim.yaml

@@ -44,6 +44,7 @@ jobs:
         - "sig-rsa validate-primary-slot ram-load multiimage"
         - "sig-rsa validate-primary-slot direct-xip multiimage"
         - "sig-ecdsa hw-rollback-protection multiimage"
+        - "overwrite-only delta-dfu,sig-ecdsa overwrite-only delta-dfu,sig-ecdsa overwrite-only delta-dfu hw-rollback-protection"
         - "sig-ed25519 sig-second-key"
         # Logical sectors: swap bookkeeping in fixed 4K units
         # independent of the physical page layout. Covers each

boot/bootutil/CMakeLists.txt

@@ -22,6 +22,7 @@ target_sources(bootutil
         src/bootutil_img_security_cnt.c
         src/bootutil_misc.c
         src/bootutil_area.c
+        src/delta.c
         src/bootutil_loader.c
         src/bootutil_public.c
         src/caps.c

boot/bootutil/include/bootutil/caps.h

@@ -54,6 +54,7 @@ uint32_t bootutil_get_caps(void);
 #define BOOTUTIL_CAP_HW_ROLLBACK_PROT       (1<<18)
 #define BOOTUTIL_CAP_ECDSA_P384             (1<<19)
 #define BOOTUTIL_CAP_SWAP_USING_OFFSET      (1<<20)
+#define BOOTUTIL_CAP_DELTA_DFU              (1<<21)
 
 /*
  * Query the number of images this bootloader is configured for.  This

boot/bootutil/include/bootutil/image.h

@@ -81,6 +81,7 @@ extern "C" {
 #define IMAGE_F_COMPRESSED_LZMA1         0x00000200
 #define IMAGE_F_COMPRESSED_LZMA2         0x00000400
 #define IMAGE_F_COMPRESSED_ARM_THUMB_FLT 0x00000800
+#define IMAGE_F_DELTA                    0x00001000
 
 /*
  * ECSDA224 is with NIST P-224
@@ -119,13 +120,13 @@ extern "C" {
 #define IMAGE_TLV_DEPENDENCY        0x40    /* Image depends on other image */
 #define IMAGE_TLV_SEC_CNT           0x50    /* security counter */
 #define IMAGE_TLV_BOOT_RECORD       0x60    /* measured boot record */
-/* The following flags relate to compressed images and are for the decompressed image data */
+/* The following flags relate to transformed images and their output image data */
 #define IMAGE_TLV_DECOMP_SIZE       0x70    /* Decompressed image size excluding header/TLVs */
-#define IMAGE_TLV_DECOMP_SHA        0x71    /*
-                                             * Decompressed image shaX hash, this field must match
-                                             * the format and size of the raw slot (compressed)
-                                             * shaX hash
+#define IMAGE_TLV_OUTPUT_SHA        0x71    /*
+                                             * Output image shaX hash, this field must match the
+                                             * format and size of the input image shaX hash
                                              */
+#define IMAGE_TLV_DECOMP_SHA        IMAGE_TLV_OUTPUT_SHA /* Compatibility alias */
 #define IMAGE_TLV_DECOMP_SIGNATURE  0x72    /*
                                              * Decompressed image signature, this field must match
                                              * the format and size of the raw slot (compressed)
@@ -134,6 +135,7 @@ extern "C" {
 #define IMAGE_TLV_COMP_DEC_SIZE     0x73    /* Compressed decrypted image size */
 #define IMAGE_TLV_UUID_VID          0x74    /* Vendor unique identifier */
 #define IMAGE_TLV_UUID_CID          0x75    /* Device class unique identifier */
+#define IMAGE_TLV_DELTA_BASE_SHA    0x76    /* SHA of image the delta applies to */
                                             /*
                                              * vendor reserved TLVs at xxA0-xxFF,
                                              * where xx denotes the upper byte
@@ -199,6 +201,8 @@ STRUCT_PACKED image_tlv {
 #define MUST_DECOMPRESS(fap, idx, hdr) \
     (flash_area_get_id(fap) == FLASH_AREA_IMAGE_SECONDARY(idx) && IS_COMPRESSED(hdr))
 
+#define IS_DELTA(hdr) ((hdr)->ih_flags & IMAGE_F_DELTA)
+
 _Static_assert(sizeof(struct image_header) == IMAGE_HEADER_SIZE,
                "struct image_header not required size");
 

boot/bootutil/src/bootutil_priv.h

@@ -357,6 +357,10 @@ int boot_copy_region(struct boot_loader_state *state,
 #endif
 bool boot_status_is_reset(const struct boot_status *bs);
 
+#ifdef MCUBOOT_DELTA_DFU
+int boot_delta_apply(struct boot_loader_state *state, struct boot_status *bs);
+#endif
+
 #ifdef MCUBOOT_ENC_IMAGES
 int boot_write_enc_keys(const struct flash_area *fap, const struct boot_status *bs);
 bool boot_read_enc_key(const struct flash_area *fap, uint8_t slot,

boot/bootutil/src/caps.c

@@ -83,6 +83,9 @@ uint32_t bootutil_get_caps(void)
 #if defined(MCUBOOT_HW_ROLLBACK_PROT)
     res |= BOOTUTIL_CAP_HW_ROLLBACK_PROT;
 #endif
+#if defined(MCUBOOT_DELTA_DFU)
+    res |= BOOTUTIL_CAP_DELTA_DFU;
+#endif
 
     return res;
 }