1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (c) 2020, Alexandru Gagniuc <mr.nuke.me@gmail.com>.
4  */
5 
6 #ifndef _ECDSA_H
7 #define _ECDSA_H
8 
9 #include <errno.h>
10 #include <image.h>
11 
12 /**
13  * crypto_algo API impementation for ECDSA;
14  * @see "struct crypto_algo"
15  * @{
16  */
17 /**
18  * sign() - calculate and return signature for given input data
19  *
20  * @info:	Specifies key and FIT information
21  * @data:	Pointer to the input data
22  * @data_len:	Data length
23  * @sigp:	Set to an allocated buffer holding the signature
24  * @sig_len:	Set to length of the calculated hash
25  *
26  * This computes input data signature according to selected algorithm.
27  * Resulting signature value is placed in an allocated buffer, the
28  * pointer is returned as *sigp. The length of the calculated
29  * signature is returned via the sig_len pointer argument. The caller
30  * should free *sigp.
31  *
32  * @return: 0, on success, -ve on error
33  */
34 int ecdsa_sign(struct image_sign_info *info, const struct image_region region[],
35 	       int region_count, uint8_t **sigp, uint *sig_len);
36 
37 /**
38  * add_verify_data() - Add verification information to FDT
39  *
40  * Add public key information to the FDT node, suitable for
41  * verification at run-time. The information added depends on the
42  * algorithm being used. I just copypasted this from rsa.h.
43  *
44  * @info:	Specifies key and FIT information
45  * @keydest:	Destination FDT blob for public key data
46  * @return: node offset within the FDT blob where the data was written on
47  *	success, -ENOSPC if the keydest FDT blob ran out of space, other -ve
48  *	value on other error
49  */
50 int ecdsa_add_verify_data(struct image_sign_info *info, void *keydest);
51 
52 /**
53  * verify() - Verify a signature against some data
54  *
55  * @info:	Specifies key and FIT information
56  * @data:	Pointer to the input data
57  * @data_len:	Data length
58  * @sig:	Signature
59  * @sig_len:	Number of bytes in signature
60  * Return: 0 if verified, -ve on error
61  */
62 int ecdsa_verify(struct image_sign_info *info,
63 		 const struct image_region region[], int region_count,
64 		 uint8_t *sig, uint sig_len);
65 /** @} */
66 
67 #define ECDSA256_BYTES	(256 / 8)
68 #define ECDSA384_BYTES	(384 / 8)
69 #define ECDSA521_BYTES	((521 + 7) / 8)
70 
71 #endif
72