1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
#pragma once
#include <stdint.h>
#include "crypto/s2n_ecc_evp.h"
#include "stuffer/s2n_stuffer.h"
#include "tls/s2n_crypto_constants.h"
#include "utils/s2n_blob.h"
typedef uint16_t kem_extension_size;
typedef uint16_t kem_public_key_size;
typedef uint16_t kem_private_key_size;
typedef uint16_t kem_shared_secret_size;
typedef uint16_t kem_ciphertext_key_size;
#define IN /* Indicates a necessary function input */
#define OUT /* Indicates a function output */
#if defined(S2N_LIBCRYPTO_SUPPORTS_KYBER)
#define S2N_NID_KYBER512 NID_KYBER512_R3
#define S2N_NID_KYBER768 NID_KYBER768_R3
#define S2N_NID_KYBER1024 NID_KYBER1024_R3
#else
#define S2N_NID_KYBER512 NID_undef
#define S2N_NID_KYBER768 NID_undef
#define S2N_NID_KYBER1024 NID_undef
#endif
struct s2n_kem {
const char *name;
int kem_nid;
const kem_extension_size kem_extension_id;
const kem_public_key_size public_key_length;
const kem_private_key_size private_key_length;
const kem_shared_secret_size shared_secret_key_length;
const kem_ciphertext_key_size ciphertext_length;
/* NIST Post Quantum KEM submissions require the following API for compatibility */
int (*generate_keypair)(IN const struct s2n_kem *kem, OUT uint8_t *public_key, OUT uint8_t *private_key);
int (*encapsulate)(IN const struct s2n_kem *kem, OUT uint8_t *ciphertext, OUT uint8_t *shared_secret, IN const uint8_t *public_key);
int (*decapsulate)(IN const struct s2n_kem *kem, OUT uint8_t *shared_secret, IN const uint8_t *ciphertext, IN const uint8_t *private_key);
};
struct s2n_kem_params {
const struct s2n_kem *kem;
struct s2n_blob public_key;
struct s2n_blob private_key;
struct s2n_blob shared_secret;
/* Store whether the client included the length prefix of the PQ and ECC Shares in their ClientHello, so that the
* server can match the client's behavior. For the client side, store whether it should send the length prefix. */
bool len_prefixed;
};
struct s2n_iana_to_kem {
const uint8_t iana_value[S2N_TLS_CIPHER_SUITE_LEN];
const struct s2n_kem **kems;
uint8_t kem_count;
};
struct s2n_kem_group {
const char *name;
uint16_t iana_id;
const struct s2n_ecc_named_curve *curve;
const struct s2n_kem *kem;
};
struct s2n_kem_group_params {
const struct s2n_kem_group *kem_group;
struct s2n_kem_params kem_params;
struct s2n_ecc_evp_params ecc_params;
};
extern const struct s2n_kem s2n_kyber_512_r3;
extern const struct s2n_kem s2n_kyber_768_r3;
extern const struct s2n_kem s2n_kyber_1024_r3;
#define S2N_KEM_GROUPS_COUNT 6
extern const struct s2n_kem_group *ALL_SUPPORTED_KEM_GROUPS[S2N_KEM_GROUPS_COUNT];
/* NIST curve KEM Groups */
extern const struct s2n_kem_group s2n_secp256r1_kyber_512_r3;
extern const struct s2n_kem_group s2n_secp256r1_kyber_768_r3;
extern const struct s2n_kem_group s2n_secp384r1_kyber_768_r3;
extern const struct s2n_kem_group s2n_secp521r1_kyber_1024_r3;
/* x25519 KEM Groups */
extern const struct s2n_kem_group s2n_x25519_kyber_512_r3;
extern const struct s2n_kem_group s2n_x25519_kyber_768_r3;
S2N_RESULT s2n_kem_generate_keypair(struct s2n_kem_params *kem_params);
S2N_RESULT s2n_kem_encapsulate(struct s2n_kem_params *kem_params, struct s2n_blob *ciphertext);
S2N_RESULT s2n_kem_decapsulate(struct s2n_kem_params *kem_params, const struct s2n_blob *ciphertext);
int s2n_choose_kem_with_peer_pref_list(const uint8_t iana_value[S2N_TLS_CIPHER_SUITE_LEN],
struct s2n_blob *client_kem_ids, const struct s2n_kem *server_kem_pref_list[],
const uint8_t num_server_supported_kems, const struct s2n_kem **chosen_kem);
int s2n_choose_kem_without_peer_pref_list(const uint8_t iana_value[S2N_TLS_CIPHER_SUITE_LEN],
const struct s2n_kem *server_kem_pref_list[], const uint8_t num_server_supported_kems,
const struct s2n_kem **chosen_kem);
int s2n_kem_free(struct s2n_kem_params *kem_params);
int s2n_kem_group_free(struct s2n_kem_group_params *kem_group_params);
int s2n_cipher_suite_to_kem(const uint8_t iana_value[S2N_TLS_CIPHER_SUITE_LEN],
const struct s2n_iana_to_kem **supported_params);
int s2n_get_kem_from_extension_id(kem_extension_size kem_id, const struct s2n_kem **kem);
int s2n_kem_send_public_key(struct s2n_stuffer *out, struct s2n_kem_params *kem_params);
int s2n_kem_recv_public_key(struct s2n_stuffer *in, struct s2n_kem_params *kem_params);
int s2n_kem_send_ciphertext(struct s2n_stuffer *out, struct s2n_kem_params *kem_params);
int s2n_kem_recv_ciphertext(struct s2n_stuffer *in, struct s2n_kem_params *kem_params);
bool s2n_kem_group_is_available(const struct s2n_kem_group *kem_group);
/* The following are API signatures for PQ KEMs as defined by NIST. All functions return 0
* on success, and !0 on failure. Avoid calling these functions directly within s2n. Instead,
* use s2n_kem_{generate_keypair, encapsulate, decapsulate}, or
* s2n_kem_{send_public_key, recv_public_key, send_ciphertext, recv_ciphertext}.
*
* int *_keypair(OUT pk, OUT sk) - Generate public/private keypair
* pk - generated public key
* sk - generated secret key
*
* int *_enc(OUT ct, OUT ss, IN pk) - Generate a shared secret and encapsulate it
* ct - key encapsulation message (ciphertext)
* ss - plaintext shared secret
* pk - public key to use for encapsulation
*
* int *_dec(OUT ss, IN ct, IN sk) - Decapsulate a key encapsulation message and recover the shared secret
* ss - plaintext shared secret
* ct - key encapsulation message (ciphertext)
* sk - secret key to use for decapsulation */
/* If s2n is compiled with support for PQ crypto, these functions will be defined in the respective KEM directories.
* If s2n is compiled without support for PQ, stubs of these functions are defined in s2n_kem.c. */
/* sikep503r1 */
/* kyber512r3 */
#define S2N_KYBER_512_R3_PUBLIC_KEY_BYTES 800
#define S2N_KYBER_512_R3_SECRET_KEY_BYTES 1632
#define S2N_KYBER_512_R3_CIPHERTEXT_BYTES 768
#define S2N_KYBER_512_R3_SHARED_SECRET_BYTES 32
int s2n_kyber_512_r3_crypto_kem_keypair(IN const struct s2n_kem *kem, OUT uint8_t *pk, OUT uint8_t *sk);
int s2n_kyber_512_r3_crypto_kem_enc(IN const struct s2n_kem *kem, OUT uint8_t *ct, OUT uint8_t *ss, IN const uint8_t *pk);
int s2n_kyber_512_r3_crypto_kem_dec(IN const struct s2n_kem *kem, OUT uint8_t *ss, IN const uint8_t *ct, IN const uint8_t *sk);
/* kyber768r3 */
#define S2N_KYBER_768_R3_PUBLIC_KEY_BYTES 1184
#define S2N_KYBER_768_R3_SECRET_KEY_BYTES 2400
#define S2N_KYBER_768_R3_CIPHERTEXT_BYTES 1088
#define S2N_KYBER_768_R3_SHARED_SECRET_BYTES 32
/* kyber1024r3 */
#define S2N_KYBER_1024_R3_PUBLIC_KEY_BYTES 1568
#define S2N_KYBER_1024_R3_SECRET_KEY_BYTES 3168
#define S2N_KYBER_1024_R3_CIPHERTEXT_BYTES 1568
#define S2N_KYBER_1024_R3_SHARED_SECRET_BYTES 32
|
