[PATCH v4 2/6] lib: ecdsa: Add skeleton to implement ecdsa verification in u-boot

Alexandru Gagniuc
2021-04-15T20:05:05Z

Prepare the source tree for accepting implementations of the ECDSA
algorithm. This patch deals with the boring aspects of Makefiles and
Kconfig files.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
---
include/image.h | 10 +++++-----
include/u-boot/rsa.h | 2 +-
lib/Kconfig | 1 +
lib/Makefile | 1 +
lib/ecdsa/Kconfig | 23 +++++++++++++++++++++++
lib/ecdsa/Makefile | 1 +
lib/ecdsa/ecdsa-verify.c | 13 +++++++++++++
7 files changed, 45 insertions(+), 6 deletions(-)
create mode 100644 lib/ecdsa/Kconfig
create mode 100644 lib/ecdsa/Makefile
create mode 100644 lib/ecdsa/ecdsa-verify.c

diff --git a/include/image.h b/include/image.h
index 3ff3c035a7..9b95f6783b 100644
--- a/include/image.h
+++ b/include/image.h
@@ -1224,20 +1224,20 @@ int calculate_hash(const void *data, int data_len, const char *algo,
#if defined(USE_HOSTCC)
# if defined(CONFIG_FIT_SIGNATURE)
# define IMAGE_ENABLE_SIGN 1
-# define IMAGE_ENABLE_VERIFY 1
+# define IMAGE_ENABLE_VERIFY_RSA 1
# define IMAGE_ENABLE_VERIFY_ECDSA 1
# define FIT_IMAGE_ENABLE_VERIFY 1
# include <openssl/evp.h>
# else
# define IMAGE_ENABLE_SIGN 0
-# define IMAGE_ENABLE_VERIFY 0
+# define IMAGE_ENABLE_VERIFY_RSA 0
# define IMAGE_ENABLE_VERIFY_ECDSA 0
# define FIT_IMAGE_ENABLE_VERIFY 0
# endif
#else
# define IMAGE_ENABLE_SIGN 0
-# define IMAGE_ENABLE_VERIFY CONFIG_IS_ENABLED(RSA_VERIFY)
-# define IMAGE_ENABLE_VERIFY_ECDSA 0
+# define IMAGE_ENABLE_VERIFY_RSA CONFIG_IS_ENABLED(RSA_VERIFY)
+# define IMAGE_ENABLE_VERIFY_ECDSA CONFIG_IS_ENABLED(ECDSA_VERIFY)
# define FIT_IMAGE_ENABLE_VERIFY CONFIG_IS_ENABLED(FIT_SIGNATURE)
#endif

@@ -1293,7 +1293,7 @@ struct image_region {
int size;
};

-#if IMAGE_ENABLE_VERIFY
+#if FIT_IMAGE_ENABLE_VERIFY
# include <u-boot/hash-checksum.h>
#endif
struct checksum_algo {
diff --git a/include/u-boot/rsa.h b/include/u-boot/rsa.h
index bed1c097c2..eb258fca4c 100644
--- a/include/u-boot/rsa.h
+++ b/include/u-boot/rsa.h
@@ -81,7 +81,7 @@ static inline int rsa_add_verify_data(struct image_sign_info *info,
}
#endif

-#if IMAGE_ENABLE_VERIFY
+#if IMAGE_ENABLE_VERIFY_RSA
/**
* rsa_verify_hash() - Verify a signature against a hash
*
diff --git a/lib/Kconfig b/lib/Kconfig
index ab8c9ccd60..584ab7b536 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -295,6 +295,7 @@ config AES
supported by the algorithm but only a 128-bit key is supported at
present.

+source lib/ecdsa/Kconfig
source lib/rsa/Kconfig
source lib/crypto/Kconfig

diff --git a/lib/Makefile b/lib/Makefile
index 6825671955..2c7c145a27 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -60,6 +60,7 @@ endif

obj-$(CONFIG_$(SPL_)ACPIGEN) += acpi/
obj-$(CONFIG_$(SPL_)MD5) += md5.o
+obj-$(CONFIG_ECDSA) += ecdsa/
obj-$(CONFIG_$(SPL_)RSA) += rsa/
obj-$(CONFIG_FIT_SIGNATURE) += hash-checksum.o
obj-$(CONFIG_SHA1) += sha1.o
diff --git a/lib/ecdsa/Kconfig b/lib/ecdsa/Kconfig
new file mode 100644
index 0000000000..a95c4ff581
--- /dev/null
+++ b/lib/ecdsa/Kconfig
@@ -0,0 +1,23 @@
+config ECDSA
+ bool "Enable ECDSA support"
+ depends on DM
+ help
+ This enables the ECDSA (elliptic curve signature) algorithm for FIT
+ image verification in U-Boot. The ECDSA algorithm is implemented
+ using the driver model, so CONFIG_DM is required by this library.
+ See doc/uImage.FIT/signature.txt for more details.
+ ECDSA is enabled for mkimage regardless of this option.
+
+if ECDSA
+
+config ECDSA_VERIFY
+ bool "Enable ECDSA verification support in U-Boot."
+ help
+ Allow ECDSA signatures to be recognized and verified in U-Boot.
+
+config SPL_ECDSA_VERIFY
+ bool "Enable ECDSA verification support in SPL"
+ help
+ Allow ECDSA signatures to be recognized and verified in SPL.
+
+endif
diff --git a/lib/ecdsa/Makefile b/lib/ecdsa/Makefile
new file mode 100644
index 0000000000..771d6d3135
--- /dev/null
+++ b/lib/ecdsa/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_$(SPL_)ECDSA_VERIFY) += ecdsa-verify.o
diff --git a/lib/ecdsa/ecdsa-verify.c b/lib/ecdsa/ecdsa-verify.c
new file mode 100644
index 0000000000..d2e6a40f4a
--- /dev/null
+++ b/lib/ecdsa/ecdsa-verify.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2020, Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ */
+
+#include <u-boot/ecdsa.h>
+
+int ecdsa_verify(struct image_sign_info *info,
+ const struct image_region region[], int region_count,
+ uint8_t *sig, uint sig_len)
+{
+ return -EOPNOTSUPP;
+}
--
2.26.3