rsa: add CONFIG_RSA_VERIFY_WITH_PKEY config
In the next couple of commits, under new CONFIG_RSA_VERIFY_WITH_PKEY,
rsa_verify() will be extended to be able to perform RSA decryption without
additional RSA key properties from FIT image, i.e. rr and n0inv.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/rsa/Kconfig b/lib/rsa/Kconfig
index 18a075c..8969721 100644
--- a/lib/rsa/Kconfig
+++ b/lib/rsa/Kconfig
@@ -28,6 +28,20 @@
help
Add RSA signature verification support.
+config RSA_VERIFY_WITH_PKEY
+ bool "Execute RSA verification without key parameters from FDT"
+ select RSA_VERIFY
+ help
+ The standard RSA-signature verification code (FIT_SIGNATURE) uses
+ pre-calculated key properties, that are stored in fdt blob, in
+ decrypting a signature.
+ This does not suit the use case where there is no way defined to
+ provide such additional key properties in standardized form,
+ particularly UEFI secure boot.
+ This options enables RSA signature verification with a public key
+ directly specified in image_sign_info, where all the necessary
+ key properties will be calculated on the fly in verification code.
+
config RSA_SOFTWARE_EXP
bool "Enable driver for RSA Modular Exponentiation in software"
depends on DM