1  /* SPDX-License-Identifier: GPL-2.0-or-later */
2  /*
3   * RSA internal helpers
4   *
5   * Copyright (c) 2015, Intel Corporation
6   * Authors: Tadeusz Struk <tadeusz.struk@intel.com>
7   */
8  #ifndef _RSA_HELPER_
9  #define _RSA_HELPER_
10  #include <linux/types.h>
11  #include <crypto/akcipher.h>
12  
13  /**
14   * rsa_key - RSA key structure
15   * @n           : RSA modulus raw byte stream
16   * @e           : RSA public exponent raw byte stream
17   * @d           : RSA private exponent raw byte stream
18   * @p           : RSA prime factor p of n raw byte stream
19   * @q           : RSA prime factor q of n raw byte stream
20   * @dp          : RSA exponent d mod (p - 1) raw byte stream
21   * @dq          : RSA exponent d mod (q - 1) raw byte stream
22   * @qinv        : RSA CRT coefficient q^(-1) mod p raw byte stream
23   * @n_sz        : length in bytes of RSA modulus n
24   * @e_sz        : length in bytes of RSA public exponent
25   * @d_sz        : length in bytes of RSA private exponent
26   * @p_sz        : length in bytes of p field
27   * @q_sz        : length in bytes of q field
28   * @dp_sz       : length in bytes of dp field
29   * @dq_sz       : length in bytes of dq field
30   * @qinv_sz     : length in bytes of qinv field
31   */
32  struct rsa_key {
33  	const u8 *n;
34  	const u8 *e;
35  	const u8 *d;
36  	const u8 *p;
37  	const u8 *q;
38  	const u8 *dp;
39  	const u8 *dq;
40  	const u8 *qinv;
41  	size_t n_sz;
42  	size_t e_sz;
43  	size_t d_sz;
44  	size_t p_sz;
45  	size_t q_sz;
46  	size_t dp_sz;
47  	size_t dq_sz;
48  	size_t qinv_sz;
49  };
50  
51  int rsa_parse_pub_key(struct rsa_key *rsa_key, const void *key,
52  		      unsigned int key_len);
53  
54  int rsa_parse_priv_key(struct rsa_key *rsa_key, const void *key,
55  		       unsigned int key_len);
56  
57  #define RSA_PUB (true)
58  #define RSA_PRIV (false)
59  
rsa_set_key(struct crypto_akcipher * child,unsigned int * key_size,bool is_pubkey,const void * key,unsigned int keylen)60  static inline int rsa_set_key(struct crypto_akcipher *child,
61  			      unsigned int *key_size, bool is_pubkey,
62  			      const void *key, unsigned int keylen)
63  {
64  	int err;
65  
66  	*key_size = 0;
67  
68  	if (is_pubkey)
69  		err = crypto_akcipher_set_pub_key(child, key, keylen);
70  	else
71  		err = crypto_akcipher_set_priv_key(child, key, keylen);
72  	if (err)
73  		return err;
74  
75  	/* Find out new modulus size from rsa implementation */
76  	err = crypto_akcipher_maxsize(child);
77  	if (err > PAGE_SIZE)
78  		return -ENOTSUPP;
79  
80  	*key_size = err;
81  	return 0;
82  }
83  
84  extern struct crypto_template rsa_pkcs1pad_tmpl;
85  extern struct crypto_template rsassa_pkcs1_tmpl;
86  #endif
87