aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/restricted/aws/s2n/tls/s2n_ecc_preferences.c
blob: 12db371abb516fe9339f5d8be79be47aab9e89c3 (plain) (blame)
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
/*
 * 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.
 */

#include <s2n.h>

#include "tls/s2n_ecc_preferences.h"
#include "tls/s2n_connection.h"
#include "crypto/s2n_ecc_evp.h"
#include "utils/s2n_safety.h"

const struct s2n_ecc_named_curve *const s2n_ecc_pref_list_20140601[] = {
    &s2n_ecc_curve_secp256r1,
    &s2n_ecc_curve_secp384r1,
};

const struct s2n_ecc_named_curve *const s2n_ecc_pref_list_20200310[] = {
#if EVP_APIS_SUPPORTED
    &s2n_ecc_curve_x25519,
#endif
    &s2n_ecc_curve_secp256r1,
    &s2n_ecc_curve_secp384r1,
};

const struct s2n_ecc_named_curve *const s2n_ecc_pref_list_20201021[] = {
    &s2n_ecc_curve_secp256r1,
    &s2n_ecc_curve_secp384r1,
    &s2n_ecc_curve_secp521r1,
};

const struct s2n_ecc_named_curve *const s2n_ecc_pref_list_test_all[] = {
#if EVP_APIS_SUPPORTED
    &s2n_ecc_curve_x25519,
#endif
    &s2n_ecc_curve_secp256r1,
    &s2n_ecc_curve_secp384r1,
    &s2n_ecc_curve_secp521r1,
};

const struct s2n_ecc_preferences s2n_ecc_preferences_20140601 = {
        .count = s2n_array_len(s2n_ecc_pref_list_20140601),
        .ecc_curves = s2n_ecc_pref_list_20140601,
};

const struct s2n_ecc_preferences s2n_ecc_preferences_20200310 = {
        .count = s2n_array_len(s2n_ecc_pref_list_20200310),
        .ecc_curves = s2n_ecc_pref_list_20200310,
};

const struct s2n_ecc_preferences s2n_ecc_preferences_20201021 = {
        .count = s2n_array_len(s2n_ecc_pref_list_20201021),
        .ecc_curves = s2n_ecc_pref_list_20201021,
};

const struct s2n_ecc_preferences s2n_ecc_preferences_test_all = {
        .count = s2n_array_len(s2n_ecc_pref_list_test_all),
        .ecc_curves = s2n_ecc_pref_list_test_all,
};

const struct s2n_ecc_preferences s2n_ecc_preferences_null = {
        .count = 0,
        .ecc_curves = NULL,
};

/* Checks if the ecc_curves present in s2n_ecc_preferences list is a subset of s2n_all_supported_curves_list
 * maintained in s2n_ecc_evp.c */
int s2n_check_ecc_preferences_curves_list(const struct s2n_ecc_preferences *ecc_preferences) {
    int check = 1;
    for (int i = 0; i < ecc_preferences->count; i++) {
        const struct s2n_ecc_named_curve *named_curve = ecc_preferences->ecc_curves[i];
        int curve_found = 0;
        for (int j = 0; j < s2n_all_supported_curves_list_len; j++) {
            if (named_curve->iana_id == s2n_all_supported_curves_list[j]->iana_id) {
                curve_found = 1;
                break; 
            }
        }
        check *= curve_found; 
        if (check == 0) {
            S2N_ERROR(S2N_ERR_ECDHE_UNSUPPORTED_CURVE);
        }
    }
    return S2N_SUCCESS;
}

/* Determines if query_iana_id corresponds to a curve for these ECC preferences. */
bool s2n_ecc_preferences_includes_curve(const struct s2n_ecc_preferences *ecc_preferences, uint16_t query_iana_id) {
    if (ecc_preferences == NULL) {
        return false;
    }

    for (size_t i = 0; i < ecc_preferences->count; i++) {
        if (query_iana_id == ecc_preferences->ecc_curves[i]->iana_id) {
            return true;
        }
    }

    return false;
}