[PATCH] lib: rsa: check algo match in rsa_verify_with_keynode

[Matthieu CASTET]

The algo name should match between the FIT's signature node and the
U-Boot's control FDT.

If we do not check it, U-Boot's control FDT can expect sha512 hash but
nothing will prevent to accept image with sha1 hash if the signature is correct.

Signed-off-by: Matthieu CASTET <castet.matthieu at free.fr>
---
 lib/rsa/rsa-verify.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c
index 2057f6819d..b9c800c7dc 100644
--- a/lib/rsa/rsa-verify.c
+++ b/lib/rsa/rsa-verify.c
@@ -439,12 +439,17 @@ static int rsa_verify_with_keynode(struct image_sign_info *info,
 	struct key_prop prop;
 	int length;
 	int ret = 0;
+	const char *algo;
 
 	if (node < 0) {
 		debug("%s: Skipping invalid node", __func__);
 		return -EBADF;
 	}
 
+	algo = fdt_getprop(blob, node, "algo", NULL);
+	if (strcmp(info->name, algo))
+		return -EFAULT;
+
 	prop.num_bits = fdtdec_get_int(blob, node, "rsa,num-bits", 0);
 
 	prop.n0inv = fdtdec_get_int(blob, node, "rsa,n0-inverse", 0);
-- 
2.28.0