xref: /freebsd/contrib/wpa/src/common/sae.h (revision 3231251399f9e60fc7175b6352eb5291e9296fe8)
1 /*
2  * Simultaneous authentication of equals
3  * Copyright (c) 2012-2013, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #ifndef SAE_H
10 #define SAE_H
11 
12 #define SAE_KCK_LEN 32
13 #define SAE_PMK_LEN 32
14 #define SAE_PMKID_LEN 16
15 #define SAE_KEYSEED_KEY_LEN 32
16 #define SAE_MAX_PRIME_LEN 512
17 #define SAE_MAX_ECC_PRIME_LEN 66
18 #define SAE_COMMIT_MAX_LEN (2 + 3 * SAE_MAX_PRIME_LEN)
19 #define SAE_CONFIRM_MAX_LEN (2 + SAE_MAX_PRIME_LEN)
20 
21 /* Special value returned by sae_parse_commit() */
22 #define SAE_SILENTLY_DISCARD 65535
23 
24 struct sae_temporary_data {
25 	u8 kck[SAE_KCK_LEN];
26 	struct crypto_bignum *own_commit_scalar;
27 	struct crypto_bignum *own_commit_element_ffc;
28 	struct crypto_ec_point *own_commit_element_ecc;
29 	struct crypto_bignum *peer_commit_element_ffc;
30 	struct crypto_ec_point *peer_commit_element_ecc;
31 	struct crypto_ec_point *pwe_ecc;
32 	struct crypto_bignum *pwe_ffc;
33 	struct crypto_bignum *sae_rand;
34 	struct crypto_ec *ec;
35 	int prime_len;
36 	const struct dh_group *dh;
37 	const struct crypto_bignum *prime;
38 	const struct crypto_bignum *order;
39 	struct crypto_bignum *prime_buf;
40 	struct crypto_bignum *order_buf;
41 	struct wpabuf *anti_clogging_token;
42 	char *pw_id;
43 };
44 
45 enum sae_state {
46 	SAE_NOTHING, SAE_COMMITTED, SAE_CONFIRMED, SAE_ACCEPTED
47 };
48 
49 struct sae_data {
50 	enum sae_state state;
51 	u16 send_confirm;
52 	u8 pmk[SAE_PMK_LEN];
53 	u8 pmkid[SAE_PMKID_LEN];
54 	struct crypto_bignum *peer_commit_scalar;
55 	int group;
56 	unsigned int sync; /* protocol instance variable: Sync */
57 	u16 rc; /* protocol instance variable: Rc (received send-confirm) */
58 	struct sae_temporary_data *tmp;
59 };
60 
61 int sae_set_group(struct sae_data *sae, int group);
62 void sae_clear_temp_data(struct sae_data *sae);
63 void sae_clear_data(struct sae_data *sae);
64 
65 int sae_prepare_commit(const u8 *addr1, const u8 *addr2,
66 		       const u8 *password, size_t password_len,
67 		       const char *identifier, struct sae_data *sae);
68 int sae_process_commit(struct sae_data *sae);
69 void sae_write_commit(struct sae_data *sae, struct wpabuf *buf,
70 		      const struct wpabuf *token, const char *identifier);
71 u16 sae_parse_commit(struct sae_data *sae, const u8 *data, size_t len,
72 		     const u8 **token, size_t *token_len, int *allowed_groups);
73 void sae_write_confirm(struct sae_data *sae, struct wpabuf *buf);
74 int sae_check_confirm(struct sae_data *sae, const u8 *data, size_t len);
75 u16 sae_group_allowed(struct sae_data *sae, int *allowed_groups, u16 group);
76 const char * sae_state_txt(enum sae_state state);
77 
78 #endif /* SAE_H */
79