1 // Copyright 2019 Espressif Systems (Shanghai) PTE LTD
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #ifdef CONFIG_WPA3_SAE
16
17 #include "common/sae.h"
18 #include "common/ieee802_11_defs.h"
19 #include "esp_wifi_driver.h"
20 #include "rsn_supp/wpa.h"
21
22 static struct sae_data g_sae_data;
23 static struct wpabuf *g_sae_token = NULL;
24 static struct wpabuf *g_sae_commit = NULL;
25 static struct wpabuf *g_sae_confirm = NULL;
26 int g_allowed_groups[] = { IANA_SECP256R1, 0 };
27
wpa3_build_sae_commit(u8 * bssid)28 static esp_err_t wpa3_build_sae_commit(u8 *bssid)
29 {
30 int default_group = IANA_SECP256R1;
31 u32 len = 0;
32 u8 own_addr[ETH_ALEN];
33 const u8 *pw;
34
35 if (wpa_sta_cur_pmksa_matches_akm()) {
36 wpa_printf(MSG_INFO, "wpa3: Skip SAE and use cached PMK instead");
37 return ESP_FAIL;
38 }
39
40 if (g_sae_commit) {
41 wpabuf_free(g_sae_commit);
42 g_sae_commit = NULL;
43 }
44
45 if (g_sae_token) {
46 len = wpabuf_len(g_sae_token);
47 goto reuse_data;
48 }
49
50 memset(&g_sae_data, 0, sizeof(g_sae_data));
51 if (sae_set_group(&g_sae_data, default_group)) {
52 wpa_printf(MSG_ERROR, "wpa3: could not set SAE group %d", default_group);
53 return ESP_FAIL;
54 }
55
56 esp_wifi_get_macaddr_internal(WIFI_IF_STA, own_addr);
57 if (!bssid) {
58 wpa_printf(MSG_ERROR, "wpa3: cannot prepare SAE commit with no BSSID!");
59 return ESP_FAIL;
60 }
61
62 pw = (const u8 *)esp_wifi_sta_get_prof_password_internal();
63 if (sae_prepare_commit(own_addr, bssid, pw, strlen((const char *)pw), NULL, &g_sae_data) < 0) {
64 wpa_printf(MSG_ERROR, "wpa3: failed to prepare SAE commit!");
65 return ESP_FAIL;
66 }
67
68 reuse_data:
69 len += SAE_COMMIT_MAX_LEN;
70 g_sae_commit = wpabuf_alloc(len);
71 if (!g_sae_commit) {
72 wpa_printf(MSG_ERROR, "wpa3: failed to allocate buffer for commit msg");
73 return ESP_FAIL;
74 }
75
76 if (sae_write_commit(&g_sae_data, g_sae_commit, g_sae_token, NULL) != ESP_OK) {
77 wpa_printf(MSG_ERROR, "wpa3: failed to write SAE commit msg");
78 wpabuf_free(g_sae_commit);
79 g_sae_commit = NULL;
80 return ESP_FAIL;
81 }
82
83 if (g_sae_token) {
84 wpabuf_free(g_sae_token);
85 g_sae_token = NULL;
86 }
87 g_sae_data.state = SAE_COMMITTED;
88
89 return ESP_OK;
90 }
91
wpa3_build_sae_confirm(void)92 static esp_err_t wpa3_build_sae_confirm(void)
93 {
94 if (g_sae_data.state != SAE_COMMITTED)
95 return ESP_FAIL;
96
97 if (g_sae_confirm) {
98 wpabuf_free(g_sae_confirm);
99 g_sae_confirm = NULL;
100 }
101
102 g_sae_confirm = wpabuf_alloc(SAE_COMMIT_MAX_LEN);
103 if (!g_sae_confirm) {
104 wpa_printf(MSG_ERROR, "wpa3: failed to allocate buffer for confirm msg");
105 return ESP_FAIL;
106 }
107
108 if (sae_write_confirm(&g_sae_data, g_sae_confirm) != ESP_OK) {
109 wpa_printf(MSG_ERROR, "wpa3: failed to write SAE confirm msg");
110 wpabuf_free(g_sae_confirm);
111 g_sae_confirm = NULL;
112 return ESP_FAIL;
113 }
114 g_sae_data.state = SAE_CONFIRMED;
115
116 return ESP_OK;
117 }
118
esp_wpa3_free_sae_data(void)119 void esp_wpa3_free_sae_data(void)
120 {
121 if (g_sae_commit) {
122 wpabuf_free(g_sae_commit);
123 g_sae_commit = NULL;
124 }
125
126 if (g_sae_confirm) {
127 wpabuf_free(g_sae_confirm);
128 g_sae_confirm = NULL;
129 }
130 sae_clear_data(&g_sae_data);
131 }
132
wpa3_build_sae_msg(u8 * bssid,u32 sae_msg_type,size_t * sae_msg_len)133 static u8 *wpa3_build_sae_msg(u8 *bssid, u32 sae_msg_type, size_t *sae_msg_len)
134 {
135 u8 *buf = NULL;
136
137 switch (sae_msg_type) {
138 case SAE_MSG_COMMIT:
139 if (ESP_OK != wpa3_build_sae_commit(bssid))
140 return NULL;
141 *sae_msg_len = wpabuf_len(g_sae_commit);
142 buf = wpabuf_mhead_u8(g_sae_commit);
143 break;
144 case SAE_MSG_CONFIRM:
145 if (ESP_OK != wpa3_build_sae_confirm())
146 return NULL;
147 *sae_msg_len = wpabuf_len(g_sae_confirm);
148 buf = wpabuf_mhead_u8(g_sae_confirm);
149 break;
150 default:
151 break;
152 }
153
154 return buf;
155 }
156
wpa3_parse_sae_commit(u8 * buf,u32 len,u16 status)157 static int wpa3_parse_sae_commit(u8 *buf, u32 len, u16 status)
158 {
159 int ret;
160
161 if (g_sae_data.state != SAE_COMMITTED) {
162 wpa_printf(MSG_ERROR, "wpa3: failed to parse SAE commit in state(%d)!",
163 g_sae_data.state);
164 return ESP_FAIL;
165 }
166
167 if (status == WLAN_STATUS_ANTI_CLOGGING_TOKEN_REQ) {
168 if (g_sae_token)
169 wpabuf_free(g_sae_token);
170 g_sae_token = wpabuf_alloc_copy(buf + 2, len - 2);
171 return ESP_OK;
172 }
173
174 ret = sae_parse_commit(&g_sae_data, buf, len, NULL, 0, g_allowed_groups);
175 if (ret) {
176 wpa_printf(MSG_ERROR, "wpa3: could not parse commit(%d)", ret);
177 return ret;
178 }
179
180 ret = sae_process_commit(&g_sae_data);
181 if (ret) {
182 wpa_printf(MSG_ERROR, "wpa3: could not process commit(%d)", ret);
183 return ret;
184 }
185
186 return ESP_OK;
187 }
188
wpa3_parse_sae_confirm(u8 * buf,u32 len)189 static int wpa3_parse_sae_confirm(u8 *buf, u32 len)
190 {
191 if (g_sae_data.state != SAE_CONFIRMED) {
192 wpa_printf(MSG_ERROR, "wpa3: failed to parse SAE commit in state(%d)!",
193 g_sae_data.state);
194 return ESP_FAIL;
195 }
196
197 if (sae_check_confirm(&g_sae_data, buf, len) != ESP_OK) {
198 wpa_printf(MSG_ERROR, "wpa3: failed to parse SAE confirm");
199 return ESP_FAIL;
200 }
201 g_sae_data.state = SAE_ACCEPTED;
202
203 wpa_set_pmk(g_sae_data.pmk, g_sae_data.pmkid, true);
204
205 return ESP_OK;
206 }
207
wpa3_parse_sae_msg(u8 * buf,size_t len,u32 sae_msg_type,u16 status)208 static int wpa3_parse_sae_msg(u8 *buf, size_t len, u32 sae_msg_type, u16 status)
209 {
210 int ret = ESP_OK;
211
212 switch (sae_msg_type) {
213 case SAE_MSG_COMMIT:
214 ret = wpa3_parse_sae_commit(buf, len, status);
215 break;
216 case SAE_MSG_CONFIRM:
217 ret = wpa3_parse_sae_confirm(buf, len);
218 esp_wpa3_free_sae_data();
219 break;
220 default:
221 wpa_printf(MSG_ERROR, "wpa3: Invalid SAE msg type(%d)!", sae_msg_type);
222 ret = ESP_FAIL;
223 break;
224 }
225
226 return ret;
227 }
228
esp_wifi_register_wpa3_cb(struct wpa_funcs * wpa_cb)229 void esp_wifi_register_wpa3_cb(struct wpa_funcs *wpa_cb)
230 {
231 wpa_cb->wpa3_build_sae_msg = wpa3_build_sae_msg;
232 wpa_cb->wpa3_parse_sae_msg = wpa3_parse_sae_msg;
233 }
234
235 #endif /* CONFIG_WPA3_SAE */
236
