/* * 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 of len equal to sig_len */ int rsa_mod_exp_sw(const uint8_t *sig, uint32_t sig_len, struct key_prop *node, uint8_t *out); int rsa_mod_exp(struct udevice *dev, const uint8_t *sig, uint32_t sig_len, struct key_prop *node, uint8_t *out); /** * struct struct mod_exp_ops - Driver model for RSA Modular Exponentiation * operations * * The uclass interface is implemented by all crypto devices which use * driver model. */ struct mod_exp_ops { /** * Perform Modular Exponentiation * * Operation: out[] = sig ^ exponent % modulus * * @dev: RSA Device * @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 of len equal to sig_len * * This function computes exponentiation over the signature. * Returns: 0 if exponentiation is successful, or a negative value * if it wasn't. */ int (*mod_exp)(struct udevice *dev, const uint8_t *sig, uint32_t sig_len, struct key_prop *node, uint8_t *outp); }; #endif