[PATCH v5 12/15] boot: pre-load: add support of ecdsa

[Philippe Reynes]

Right now, u-boot can only boot image with a
pre-load header with rsa. We add the support
of ecdsa.

Reviewed-by: Simon Glass <sjg at chromium.org>
Signed-off-by: Philippe Reynes <philippe.reynes at softathome.com>
---
v3:
- initial version
v4:
- avoid calling image_get_crypto_algo several times
v5:
- simplify the function is_ecdsa
- re-use already computed crypto in function image_pre_load_sig_setup

 boot/image-pre-load.c | 53 +++++++++++++++++++++++++++++++++----------
 1 file changed, 41 insertions(+), 12 deletions(-)

diff --git a/boot/image-pre-load.c b/boot/image-pre-load.c
index 2f851ebb28c..af72ea6d547 100644
--- a/boot/image-pre-load.c
+++ b/boot/image-pre-load.c
@@ -70,6 +70,12 @@ static int image_pre_load_sig_setup(struct image_sig_info *info)
 	return 0;
 }
 #else
+
+static int is_ecdsa(struct crypto_algo *crypto)
+{
+	return crypto && !strncmp(crypto->name, "ecdsa", 5);
+}
+
 /*
  * This function gathers information about the signature check
  * that could be done before launching the image.
@@ -86,6 +92,7 @@ static int image_pre_load_sig_setup(struct image_sig_info *info)
 	int key_len;
 	int node, ret = 0;
 	char *sig_info_path = NULL;
+	struct crypto_algo *crypto;
 
 	if (!info) {
 		log_err("ERROR: info is NULL for image pre-load sig check\n");
@@ -114,11 +121,24 @@ static int image_pre_load_sig_setup(struct image_sig_info *info)
 		goto out;
 	}
 
-	padding_name = fdt_getprop(gd_fdt_blob(), node,
-				   IMAGE_PRE_LOAD_PROP_PADDING_NAME, NULL);
-	if (!padding_name) {
-		log_info("INFO: no padding_name provided, so using pkcs-1.5\n");
-		padding_name = "pkcs-1.5";
+	crypto = image_get_crypto_algo(algo_name);
+	if (!crypto) {
+		printf("ERROR: can't find a valid crypto algo from %s\n",
+		       (char *)algo_name);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (is_ecdsa(crypto)) {
+		padding_name = NULL;
+	} else {
+		padding_name = fdt_getprop(gd_fdt_blob(), node,
+					   IMAGE_PRE_LOAD_PROP_PADDING_NAME,
+					   NULL);
+		if (!padding_name) {
+			log_info("INFO: no padding_name provided, so using pkcs-1.5\n");
+			padding_name = "pkcs-1.5";
+		}
 	}
 
 	sig_size = fdt_getprop(gd_fdt_blob(), node,
@@ -129,12 +149,17 @@ static int image_pre_load_sig_setup(struct image_sig_info *info)
 		goto out;
 	}
 
-	key = fdt_getprop(gd_fdt_blob(), node,
-			  IMAGE_PRE_LOAD_PROP_PUBLIC_KEY, &key_len);
-	if (!key) {
-		log_err("ERROR: no key for image pre-load sig check\n");
-		ret = -EINVAL;
-		goto out;
+	if (is_ecdsa(crypto)) {
+		key = NULL;
+		key_len = 0;
+	} else {
+		key = fdt_getprop(gd_fdt_blob(), node,
+				  IMAGE_PRE_LOAD_PROP_PUBLIC_KEY, &key_len);
+		if (!key) {
+			log_err("ERROR: no key for image pre-load sig check\n");
+			ret = -EINVAL;
+			goto out;
+		}
 	}
 
 	info->algo_name		= (char *)algo_name;
@@ -152,9 +177,13 @@ static int image_pre_load_sig_setup(struct image_sig_info *info)
 	info->sig_info.name     = info->algo_name;
 	info->sig_info.padding  = image_get_padding_algo(info->padding_name);
 	info->sig_info.checksum = image_get_checksum_algo(info->sig_info.name);
-	info->sig_info.crypto   = image_get_crypto_algo(info->sig_info.name);
+	info->sig_info.crypto   = crypto;
 	info->sig_info.key      = info->key;
 	info->sig_info.keylen   = info->key_len;
+	if (is_ecdsa(crypto)) {
+		info->sig_info.required_keynode = node;
+		info->sig_info.fdt_blob = gd_fdt_blob();
+	}
 
  out:
 	return ret;
-- 
2.43.0