SPL: Add signature verification when loading image

U-boot proper signature is not verified by SPL on most platforms
even config SPL_FIT_SIGNATURE is enabled. Only fsl-layerscape
platform support secure boot in platform specific code. So
verified boot cannot be achieved if u-boot proper is loaded by
SPL.

This patch add signature verification to u-boot proper images
when loading FIT image in SPL. It is tested on Allwinner bananapi
zero board with H2+ SoC.

Signed-off-by: Jun Nie <jun.nie@linaro.org>

diff --git a/common/image-fit.c b/common/image-fit.c
index f6e956a..4b03390 100644 (file)
--- a/common/image-fit.c
+++ b/common/image-fit.c
@@ -1068,34 +1068,14 @@ static int fit_image_check_hash(const void *fit, int noffset, const void *data,
        return 0;
 }
 
-/**
- * fit_image_verify - verify data integrity
- * @fit: pointer to the FIT format image header
- * @image_noffset: component image node offset
- *
- * fit_image_verify() goes over component image hash nodes,
- * re-calculates each data hash and compares with the value stored in hash
- * node.
- *
- * returns:
- *     1, if all hashes are valid
- *     0, otherwise (or on error)
- */
-int fit_image_verify(const void *fit, int image_noffset)
+int fit_image_verify_with_data(const void *fit, int image_noffset,
+                              const void *data, size_t size)
 {
-       const void      *data;
-       size_t          size;
        int             noffset = 0;
        char            *err_msg = "";
        int verify_all = 1;
        int ret;
 
-       /* Get image data and data length */
-       if (fit_image_get_data(fit, image_noffset, &data, &size)) {
-               err_msg = "Can't get image data/size";
-               goto error;
-       }
-
        /* Verify all required signatures */
        if (IMAGE_ENABLE_VERIFY &&
            fit_image_verify_required_sigs(fit, image_noffset, data, size,
@@ -1153,6 +1133,38 @@ error:
 }
 
 /**
+ * fit_image_verify - verify data integrity
+ * @fit: pointer to the FIT format image header
+ * @image_noffset: component image node offset
+ *
+ * fit_image_verify() goes over component image hash nodes,
+ * re-calculates each data hash and compares with the value stored in hash
+ * node.
+ *
+ * returns:
+ *     1, if all hashes are valid
+ *     0, otherwise (or on error)
+ */
+int fit_image_verify(const void *fit, int image_noffset)
+{
+       const void      *data;
+       size_t          size;
+       int             noffset = 0;
+       char            *err_msg = "";
+
+       /* Get image data and data length */
+       if (fit_image_get_data(fit, image_noffset, &data, &size)) {
+               err_msg = "Can't get image data/size";
+               printf("error!\n%s for '%s' hash node in '%s' image node\n",
+                      err_msg, fit_get_name(fit, noffset, NULL),
+                      fit_get_name(fit, image_noffset, NULL));
+               return 0;
+       }
+
+       return fit_image_verify_with_data(fit, image_noffset, data, size);
+}
+
+/**
  * fit_all_image_verify - verify data integrity for all images
  * @fit: pointer to the FIT format image header
  *

diff --git a/common/spl/spl_fit.c b/common/spl/spl_fit.c
index b705d03..be92ca4 100644 (file)
--- a/common/spl/spl_fit.c
+++ b/common/spl/spl_fit.c
@@ -174,6 +174,9 @@ static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
        uint8_t image_comp = -1, type = -1;
        const void *data;
        bool external_data = false;
+#ifdef CONFIG_SPL_FIT_SIGNATURE
+       int ret;
+#endif
 
        if (IS_ENABLED(CONFIG_SPL_OS_BOOT) && IS_ENABLED(CONFIG_SPL_GZIP)) {
                if (fit_image_get_comp(fit, node, &image_comp))
@@ -252,7 +255,16 @@ static int spl_load_fit_image(struct spl_load_info *info, ulong sector,
                image_info->entry_point = fdt_getprop_u32(fit, node, "entry");
        }
 
+#ifdef CONFIG_SPL_FIT_SIGNATURE
+       printf("## Checking hash(es) for Image %s ...\n",
+              fit_get_name(fit, node, NULL));
+       ret = fit_image_verify_with_data(fit, node,
+                                        (const void *)load_addr, length);
+       printf("\n");
+       return !ret;
+#else
        return 0;
+#endif
 }
 
 static int spl_fit_append_fdt(struct spl_image_info *spl_image,

diff --git a/include/image.h b/include/image.h
index dbdaecb..88e17fc 100644 (file)
--- a/include/image.h
+++ b/include/image.h
@@ -1013,6 +1013,8 @@ int fit_add_verification_data(const char *keydir, void *keydest, void *fit,
                              const char *comment, int require_keys,
                              const char *engine_id);
 
+int fit_image_verify_with_data(const void *fit, int image_noffset,
+                              const void *data, size_t size);
 int fit_image_verify(const void *fit, int noffset);
 int fit_config_verify(const void *fit, int conf_noffset);
 int fit_all_image_verify(const void *fit);