xref: /openbmc/u-boot/include/u-boot/rsa-mod-exp.h (revision 37e3a36a)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright 2014 Freescale Semiconductor, Inc.
4  */
5 
6 #ifndef _RSA_MOD_EXP_H
7 #define _RSA_MOD_EXP_H
8 
9 #include <errno.h>
10 #include <image.h>
11 
12 /**
13  * struct key_prop - holder for a public key properties
14  *
15  * The struct has pointers to modulus (Typically called N),
16  * The inverse, R^2, exponent. These can be typecasted and
17  * used as byte arrays or converted to the required format
18  * as per requirement of RSA implementation.
19  */
20 struct key_prop {
21 	const void *rr;		/* R^2 can be treated as byte array */
22 	const void *modulus;	/* modulus as byte array */
23 	const void *public_exponent; /* public exponent as byte array */
24 	uint32_t n0inv;		/* -1 / modulus[0] mod 2^32 */
25 	int num_bits;		/* Key length in bits */
26 	uint32_t exp_len;	/* Exponent length in number of uint8_t */
27 };
28 
29 /**
30  * rsa_mod_exp_sw() - Perform RSA Modular Exponentiation in sw
31  *
32  * Operation: out[] = sig ^ exponent % modulus
33  *
34  * @sig:	RSA PKCS1.5 signature
35  * @sig_len:	Length of signature in number of bytes
36  * @node:	Node with RSA key elements like modulus, exponent, R^2, n0inv
37  * @out:	Result in form of byte array of len equal to sig_len
38  */
39 int rsa_mod_exp_sw(const uint8_t *sig, uint32_t sig_len,
40 		struct key_prop *node, uint8_t *out);
41 
42 int rsa_mod_exp(struct udevice *dev, const uint8_t *sig, uint32_t sig_len,
43 		struct key_prop *node, uint8_t *out);
44 
45 #if defined(CONFIG_CMD_ZYNQ_RSA)
46 int zynq_pow_mod(u32 *keyptr, u32 *inout);
47 #endif
48 
49 /**
50  * struct struct mod_exp_ops - Driver model for RSA Modular Exponentiation
51  *				operations
52  *
53  * The uclass interface is implemented by all crypto devices which use
54  * driver model.
55  */
56 struct mod_exp_ops {
57 	/**
58 	 * Perform Modular Exponentiation
59 	 *
60 	 * Operation: out[] = sig ^ exponent % modulus
61 	 *
62 	 * @dev:	RSA Device
63 	 * @sig:	RSA PKCS1.5 signature
64 	 * @sig_len:	Length of signature in number of bytes
65 	 * @node:	Node with RSA key elements like modulus, exponent,
66 	 *		R^2, n0inv
67 	 * @out:	Result in form of byte array of len equal to sig_len
68 	 *
69 	 * This function computes exponentiation over the signature.
70 	 * Returns: 0 if exponentiation is successful, or a negative value
71 	 * if it wasn't.
72 	 */
73 	int (*mod_exp)(struct udevice *dev, const uint8_t *sig,
74 			   uint32_t sig_len, struct key_prop *node,
75 			   uint8_t *outp);
76 };
77 
78 #endif
79