rsa: add a structure for the padding

The rsa signature use a padding algorithm. By default, we use the
padding pkcs-1.5. In order to add some new padding algorithm, we
add a padding framework to manage several padding algorithm.
The choice of the padding is done in the file .its.

Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

2 files changed, 34 insertions, 0 deletions

diff --git a/common/image-fit.c b/common/image-fit.c
index 8d39a243f8d..ac901e131ca 100644
--- a/common/image-fit.c
+++ b/common/image-fit.c
@@ -165,6 +165,7 @@ static void fit_image_print_data(const void *fit, int noffset, const char *p,
 	uint8_t *value;
 	int value_len;
 	char *algo;
+	const char *padding;
 	int required;
 	int ret, i;
 
@@ -184,6 +185,10 @@ static void fit_image_print_data(const void *fit, int noffset, const char *p,
 		printf(" (required)");
 	printf("\n");
 
+	padding = fdt_getprop(fit, noffset, "padding", NULL);
+	if (padding)
+		printf("%s  %s padding: %s\n", p, type, padding);
+
 	ret = fit_image_hash_get_value(fit, noffset, &value,
 				       &value_len);
 	printf("%s  %s value:   ", p, type);
diff --git a/common/image-sig.c b/common/image-sig.c
index 5d860e12663..3d8281f2faa 100644
--- a/common/image-sig.c
+++ b/common/image-sig.c
@@ -71,6 +71,13 @@ struct crypto_algo crypto_algos[] = {
 
 };
 
+struct padding_algo padding_algos[] = {
+	{
+		.name = "pkcs-1.5",
+		.verify = padding_pkcs_15_verify,
+	},
+};
+
 struct checksum_algo *image_get_checksum_algo(const char *full_name)
 {
 	int i;
@@ -106,6 +113,21 @@ struct crypto_algo *image_get_crypto_algo(const char *full_name)
 	return NULL;
 }
 
+struct padding_algo *image_get_padding_algo(const char *name)
+{
+	int i;
+
+	if (!name)
+		return NULL;
+
+	for (i = 0; i < ARRAY_SIZE(padding_algos); i++) {
+		if (!strcmp(padding_algos[i].name, name))
+			return &padding_algos[i];
+	}
+
+	return NULL;
+}
+
 /**
  * fit_region_make_list() - Make a list of image regions
  *
@@ -155,6 +177,7 @@ static int fit_image_setup_verify(struct image_sign_info *info,
 		char **err_msgp)
 {
 	char *algo_name;
+	const char *padding_name;
 
 	if (fdt_totalsize(fit) > CONFIG_FIT_SIGNATURE_MAX_SIZE) {
 		*err_msgp = "Total size too large";
@@ -165,6 +188,11 @@ static int fit_image_setup_verify(struct image_sign_info *info,
 		*err_msgp = "Can't get hash algo property";
 		return -1;
 	}
+
+	padding_name = fdt_getprop(fit, noffset, "padding", NULL);
+	if (!padding_name)
+		padding_name = RSA_DEFAULT_PADDING_NAME;
+
 	memset(info, '\0', sizeof(*info));
 	info->keyname = fdt_getprop(fit, noffset, "key-name-hint", NULL);
 	info->fit = (void *)fit;
@@ -172,6 +200,7 @@ static int fit_image_setup_verify(struct image_sign_info *info,
 	info->name = algo_name;
 	info->checksum = image_get_checksum_algo(algo_name);
 	info->crypto = image_get_crypto_algo(algo_name);
+	info->padding = image_get_padding_algo(padding_name);
 	info->fdt_blob = gd_fdt_blob();
 	info->required_keynode = required_keynode;
 	printf("%s:%s", algo_name, info->keyname);