secure boot: Functional partition table & app signature verification

components/bootloader_support/src/bootloader_flash.c

@@ -38,7 +38,7 @@ const void *bootloader_mmap(uint32_t src_addr, uint32_t size)
     return result;
 }
 
-void bootloader_unmap(const void *mapping)
+void bootloader_munmap(const void *mapping)
 {
     if(mapping && map) {
         spi_flash_munmap(map);
@@ -68,7 +68,7 @@ const void *bootloader_mmap(uint32_t src_addr, uint32_t size)
     }
 
     uint32_t src_addr_aligned = src_addr & 0xffff0000;
-    uint32_t count = (size + 0xffff) / 0x10000;
+    uint32_t count = (size + (src_addr - src_addr_aligned) + 0xffff) / 0x10000;
     Cache_Read_Disable(0);
     Cache_Flush(0);
     ESP_LOGD(TAG, "mmu set paddr=%08x count=%d", src_addr_aligned, count );
@@ -80,7 +80,7 @@ const void *bootloader_mmap(uint32_t src_addr, uint32_t size)
     return (void *)(0x3f400000 + (src_addr - src_addr_aligned));
 }
 
-void bootloader_unmap(const void *mapping)
+void bootloader_munmap(const void *mapping)
 {
     if (mapped)  {
         /* Full MMU reset */

components/bootloader_support/src/esp_image_format.c

@@ -70,8 +70,8 @@ esp_err_t esp_image_load_segment_header(uint8_t index, uint32_t src_addr, const
                 ESP_LOGE(TAG, "invalid segment length 0x%x", segment_header->data_len);
                 err = ESP_ERR_IMAGE_INVALID;
             }
-            ESP_LOGV(TAG, "segment data length 0x%x", segment_header->data_len);
             next_addr += sizeof(esp_image_segment_header_t);
+            ESP_LOGV(TAG, "segment data length 0x%x data starts 0x%x", segment_header->data_len, next_addr);
             *segment_data_offset = next_addr;
             next_addr += segment_header->data_len;
         }
@@ -124,7 +124,7 @@ esp_err_t esp_image_basic_verify(uint32_t src_addr, uint32_t *p_length)
         for(int i = 0; i < segment_header.data_len; i++) {
             checksum ^= segment_data[i];
         }
-        bootloader_unmap(segment_data);
+        bootloader_munmap(segment_data);
     }
 
     /* End of image, verify checksum */

components/bootloader_support/src/secure_boot.c

@@ -90,7 +90,7 @@ static bool secure_boot_generate(uint32_t image_len){
     for (int i = 0; i < image_len; i+= HASH_BLOCK_SIZE) {
         ets_secure_boot_hash(image + i/sizeof(void *));
     }
-    bootloader_unmap(image);
+    bootloader_munmap(image);
 
     ets_secure_boot_obtain();
     ets_secure_boot_rd_abstract(buf);

components/bootloader_support/src/secure_boot_signatures.c

@@ -43,9 +43,10 @@ extern const uint8_t signature_verification_key_end[] asm("_binary_signature_ver
 esp_err_t esp_secure_boot_verify_signature(uint32_t src_addr, uint32_t length)
 {
     sha_context sha;
-    uint8_t digest[64];
+    uint8_t digest[32];
     ptrdiff_t keylen;
-    const uint8_t *data;
+    const uint8_t *data, *digest_data;
+    uint32_t digest_len, chunk_len;
     const signature_block_t *sigblock;
     bool is_valid;
 
@@ -68,16 +69,23 @@ esp_err_t esp_secure_boot_verify_signature(uint32_t src_addr, uint32_t length)
     /* Use ROM SHA functions directly */
     ets_sha_enable();
     ets_sha_init(&sha);
-    ets_sha_update(&sha, SHA2_512, data, length);
-    ets_sha_finish(&sha, SHA2_512, digest);
+    digest_len = length * 8;
+    digest_data = data;
+    while (digest_len > 0) {
+        uint32_t chunk_len = (digest_len > 64) ? 64 : digest_len;
+        ets_sha_update(&sha, SHA2_256, digest_data, chunk_len);
+        digest_len -= chunk_len;
+        digest_data += chunk_len / 8;
+    }
+    ets_sha_finish(&sha, SHA2_256, digest);
     ets_sha_disable();
 #else
     /* Use thread-safe esp-idf SHA layer */
-    esp_sha512_init(&sha);
-    esp_sha512_start(&sha, false);
-    esp_sha512_update(&sha, data, length);
-    esp_sha512_finish(&sha, digest);
-    esp_sha512_free(&sha);
+    esp_sha256_init(&sha);
+    esp_sha256_start(&sha, false);
+    esp_sha256_update(&sha, data, length);
+    esp_sha256_finish(&sha, digest);
+    esp_sha256_free(&sha);
 #endif
 
     keylen = signature_verification_key_end - signature_verification_key_start;
@@ -90,10 +98,10 @@ esp_err_t esp_secure_boot_verify_signature(uint32_t src_addr, uint32_t length)
                            digest, sizeof(digest), sigblock->signature,
                            uECC_secp256r1());
 
-    bootloader_unmap(data);
+    bootloader_munmap(data);
     return is_valid ? ESP_OK : ESP_ERR_IMAGE_INVALID;
 
  unmap_and_fail:
-    bootloader_unmap(data);
+    bootloader_munmap(data);
     return ESP_FAIL;
 }