mkimage: fit: add support to encrypt image with aes

This commit add the support of encrypting image with aes
in mkimage. To enable the ciphering, a node cipher with
a reference to a key and IV (Initialization Vector) must
be added to the its file. Then mkimage add the encrypted
image to the FIT and add the key and IV to the u-boot
device tree.

Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/common/image-fit.c b/common/image-fit.c
index 231612ff5f..6b50ceba1a 100644
--- a/common/image-fit.c
+++ b/common/image-fit.c
@@ -1080,6 +1080,33 @@ static int fit_image_hash_get_ignore(const void *fit, int noffset, int *ignore)
 	return 0;
 }
 
+/**
+ * fit_image_cipher_get_algo - get cipher algorithm name
+ * @fit: pointer to the FIT format image header
+ * @noffset: cipher node offset
+ * @algo: double pointer to char, will hold pointer to the algorithm name
+ *
+ * fit_image_cipher_get_algo() finds cipher algorithm property in a given
+ * cipher node. If the property is found its data start address is returned
+ * to the caller.
+ *
+ * returns:
+ *     0, on success
+ *     -1, on failure
+ */
+int fit_image_cipher_get_algo(const void *fit, int noffset, char **algo)
+{
+	int len;
+
+	*algo = (char *)fdt_getprop(fit, noffset, FIT_ALGO_PROP, &len);
+	if (!*algo) {
+		fit_get_debug(fit, noffset, FIT_ALGO_PROP, len);
+		return -1;
+	}
+
+	return 0;
+}
+
 ulong fit_get_end(const void *fit)
 {
 	return map_to_sysmem((void *)(fit + fdt_totalsize(fit)));