1 /*
2 * Copyright (c) 2024 Nordic Semiconductor ASA
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <zephyr/logging/log.h>
9 #include <zephyr/psa/key_ids.h>
10 #include "psa/crypto.h"
11
12 #include "wifi_credentials_internal.h"
13
14 LOG_MODULE_REGISTER(wifi_credentials_backend, CONFIG_WIFI_CREDENTIALS_LOG_LEVEL);
15
16 BUILD_ASSERT(CONFIG_WIFI_CREDENTIALS_MAX_ENTRIES <= ZEPHYR_PSA_WIFI_CREDENTIALS_KEY_ID_RANGE_SIZE,
17 "Wi-Fi credentials management PSA key ID range exceeds officially allocated range.");
18
wifi_credentials_backend_init(void)19 int wifi_credentials_backend_init(void)
20 {
21 psa_status_t ret;
22 uint8_t buf[ENTRY_MAX_LEN];
23
24 for (size_t i = 0; i < CONFIG_WIFI_CREDENTIALS_MAX_ENTRIES; ++i) {
25 size_t length_read = 0;
26 size_t key_id = i + ZEPHYR_PSA_WIFI_CREDENTIALS_KEY_ID_RANGE_BEGIN;
27
28 ret = psa_export_key(key_id, buf, ARRAY_SIZE(buf), &length_read);
29 if (ret == PSA_SUCCESS && length_read == ENTRY_MAX_LEN) {
30 wifi_credentials_cache_ssid(i, (struct wifi_credentials_header *)buf);
31 } else if (ret != PSA_ERROR_INVALID_HANDLE) {
32 LOG_ERR("psa_export_key failed, err: %d", ret);
33 return -EFAULT;
34 }
35 }
36
37 return 0;
38 }
39
wifi_credentials_store_entry(size_t idx,const void * buf,size_t buf_len)40 int wifi_credentials_store_entry(size_t idx, const void *buf, size_t buf_len)
41 {
42 psa_status_t ret;
43 psa_key_attributes_t key_attributes = {0};
44 psa_key_id_t key_id;
45
46 psa_set_key_id(&key_attributes, idx + ZEPHYR_PSA_WIFI_CREDENTIALS_KEY_ID_RANGE_BEGIN);
47 psa_set_key_usage_flags(&key_attributes, PSA_KEY_USAGE_EXPORT);
48 psa_set_key_lifetime(&key_attributes, PSA_KEY_LIFETIME_PERSISTENT);
49 psa_set_key_algorithm(&key_attributes, PSA_ALG_NONE);
50 psa_set_key_type(&key_attributes, PSA_KEY_TYPE_RAW_DATA);
51 psa_set_key_bits(&key_attributes, buf_len * 8);
52
53 ret = psa_import_key(&key_attributes, buf, buf_len, &key_id);
54 if (ret == PSA_ERROR_ALREADY_EXISTS) {
55 LOG_ERR("psa_import_key failed, duplicate key: %d", ret);
56 return -EEXIST;
57 } else if (ret != PSA_SUCCESS) {
58 LOG_ERR("psa_import_key failed, err: %d", ret);
59 return -EFAULT;
60 }
61
62 return 0;
63 }
64
wifi_credentials_delete_entry(size_t idx)65 int wifi_credentials_delete_entry(size_t idx)
66 {
67 psa_status_t ret = psa_destroy_key(idx + ZEPHYR_PSA_WIFI_CREDENTIALS_KEY_ID_RANGE_BEGIN);
68
69 if (ret != PSA_SUCCESS) {
70 LOG_ERR("psa_destroy_key failed, err: %d", ret);
71 return -EFAULT;
72 }
73
74 return 0;
75 }
76
wifi_credentials_load_entry(size_t idx,void * buf,size_t buf_len)77 int wifi_credentials_load_entry(size_t idx, void *buf, size_t buf_len)
78 {
79 size_t length_read = 0;
80 size_t key_id = idx + ZEPHYR_PSA_WIFI_CREDENTIALS_KEY_ID_RANGE_BEGIN;
81 psa_status_t ret;
82
83 ret = psa_export_key(key_id, buf, buf_len, &length_read);
84 if (ret != PSA_SUCCESS) {
85 LOG_ERR("psa_export_key failed, err: %d", ret);
86 return -EFAULT;
87 }
88
89 if (buf_len != length_read) {
90 return -EIO;
91 }
92
93 return 0;
94 }
95
