diff options
author | Ruchika Gupta <ruchika.gupta@freescale.com> | 2015-01-23 16:01:50 +0530 |
---|---|---|
committer | Simon Glass <sjg@chromium.org> | 2015-01-29 17:09:58 -0700 |
commit | fc2f4246b4b3b750e8c5aa08440ec5e1c952088e (patch) | |
tree | ae15e8380d8b534d265e07d7c44e4e702d5cf273 /include | |
parent | 49cad54788a64a296567abadcd736fdbe47cc3a3 (diff) |
rsa: Split the rsa-verify to separate the modular exponentiation
Public exponentiation which is required in rsa verify functionality is
tightly integrated with verification code in rsa_verify.c. The patch
splits the file into twp separating the modular exponentiation.
1. rsa-verify.c
- The file parses device tree keys node to fill a keyprop structure.
The keyprop structure can then be converted to implementation specific
format.
(struct rsa_pub_key for sw implementation)
- The parsed device tree node is then passed to a generic rsa_mod_exp
function.
2. rsa-mod-exp.c
Move the software specific functions related to modular exponentiation
from rsa-verify.c to this file.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
CC: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/u-boot/rsa-mod-exp.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/include/u-boot/rsa-mod-exp.h b/include/u-boot/rsa-mod-exp.h new file mode 100644 index 0000000000..59cd9ea2d8 --- /dev/null +++ b/include/u-boot/rsa-mod-exp.h @@ -0,0 +1,43 @@ +/* + * Copyright (c) 2014, Ruchika Gupta. + * + * SPDX-License-Identifier: GPL-2.0+ +*/ + +#ifndef _RSA_MOD_EXP_H +#define _RSA_MOD_EXP_H + +#include <errno.h> +#include <image.h> + +/** + * struct key_prop - holder for a public key properties + * + * The struct has pointers to modulus (Typically called N), + * The inverse, R^2, exponent. These can be typecasted and + * used as byte arrays or converted to the required format + * as per requirement of RSA implementation. + */ +struct key_prop { + const void *rr; /* R^2 can be treated as byte array */ + const void *modulus; /* modulus as byte array */ + const void *public_exponent; /* public exponent as byte array */ + uint32_t n0inv; /* -1 / modulus[0] mod 2^32 */ + int num_bits; /* Key length in bits */ + uint32_t exp_len; /* Exponent length in number of uint8_t */ +}; + +/** + * rsa_mod_exp_sw() - Perform RSA Modular Exponentiation in sw + * + * Operation: out[] = sig ^ exponent % modulus + * + * @sig: RSA PKCS1.5 signature + * @sig_len: Length of signature in number of bytes + * @node: Node with RSA key elements like modulus, exponent, R^2, n0inv + * @out: Result in form of byte array + */ +int rsa_mod_exp_sw(const uint8_t *sig, uint32_t sig_len, + struct key_prop *node, uint8_t *out); + +#endif |