xref: /linux/drivers/net/wireless/intel/iwlwifi/mld/key.c (revision af2d6148d2a159e1a0862bce5a2c88c1618a2b27)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright (C) 2024 Intel Corporation
4  */
5 #include "key.h"
6 #include "iface.h"
7 #include "sta.h"
8 #include "fw/api/datapath.h"
9 
10 static u32 iwl_mld_get_key_flags(struct iwl_mld *mld,
11 				 struct ieee80211_vif *vif,
12 				 struct ieee80211_sta *sta,
13 				 struct ieee80211_key_conf *key)
14 {
15 	struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(vif);
16 	bool pairwise = key->flags & IEEE80211_KEY_FLAG_PAIRWISE;
17 	bool igtk = key->keyidx == 4 || key->keyidx == 5;
18 	u32 flags = 0;
19 
20 	if (!pairwise)
21 		flags |= IWL_SEC_KEY_FLAG_MCAST_KEY;
22 
23 	switch (key->cipher) {
24 	case WLAN_CIPHER_SUITE_TKIP:
25 		flags |= IWL_SEC_KEY_FLAG_CIPHER_TKIP;
26 		break;
27 	case WLAN_CIPHER_SUITE_AES_CMAC:
28 	case WLAN_CIPHER_SUITE_CCMP:
29 		flags |= IWL_SEC_KEY_FLAG_CIPHER_CCMP;
30 		break;
31 	case WLAN_CIPHER_SUITE_GCMP_256:
32 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
33 		flags |= IWL_SEC_KEY_FLAG_KEY_SIZE;
34 		fallthrough;
35 	case WLAN_CIPHER_SUITE_GCMP:
36 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
37 		flags |= IWL_SEC_KEY_FLAG_CIPHER_GCMP;
38 		break;
39 	}
40 
41 	if (!sta && vif->type == NL80211_IFTYPE_STATION)
42 		sta = mld_vif->ap_sta;
43 
44 	/* If we are installing an iGTK (in AP or STA mode), we need to tell
45 	 * the firmware this key will en/decrypt MGMT frames.
46 	 * Same goes if we are installing a pairwise key for an MFP station.
47 	 * In case we're installing a groupwise key (which is not an iGTK),
48 	 * then, we will not use this key for MGMT frames.
49 	 */
50 	if ((sta && sta->mfp && pairwise) || igtk)
51 		flags |= IWL_SEC_KEY_FLAG_MFP;
52 
53 	if (key->flags & IEEE80211_KEY_FLAG_SPP_AMSDU)
54 		flags |= IWL_SEC_KEY_FLAG_SPP_AMSDU;
55 
56 	return flags;
57 }
58 
59 static u32 iwl_mld_get_key_sta_mask(struct iwl_mld *mld,
60 				    struct ieee80211_vif *vif,
61 				    struct ieee80211_sta *sta,
62 				    struct ieee80211_key_conf *key)
63 {
64 	struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(vif);
65 	struct ieee80211_link_sta *link_sta;
66 	int sta_id;
67 
68 	lockdep_assert_wiphy(mld->wiphy);
69 
70 	/* AP group keys are per link and should be on the mcast/bcast STA */
71 	if (vif->type == NL80211_IFTYPE_AP &&
72 	    !(key->flags & IEEE80211_KEY_FLAG_PAIRWISE)) {
73 		struct iwl_mld_link *link = NULL;
74 
75 		if (key->link_id >= 0)
76 			link = iwl_mld_link_dereference_check(mld_vif,
77 							      key->link_id);
78 
79 		if (WARN_ON(!link))
80 			return 0;
81 
82 		/* In this stage we should have both the bcast and mcast STAs */
83 		if (WARN_ON(link->bcast_sta.sta_id == IWL_INVALID_STA ||
84 			    link->mcast_sta.sta_id == IWL_INVALID_STA))
85 			return 0;
86 
87 		/* IGTK/BIGTK to bcast STA */
88 		if (key->keyidx >= 4)
89 			return BIT(link->bcast_sta.sta_id);
90 
91 		/* GTK for data to mcast STA */
92 		return BIT(link->mcast_sta.sta_id);
93 	}
94 
95 	/* for client mode use the AP STA also for group keys */
96 	if (!sta && vif->type == NL80211_IFTYPE_STATION)
97 		sta = mld_vif->ap_sta;
98 
99 	/* STA should be non-NULL now */
100 	if (WARN_ON(!sta))
101 		return 0;
102 
103 	/* Key is not per-link, get the full sta mask */
104 	if (key->link_id < 0)
105 		return iwl_mld_fw_sta_id_mask(mld, sta);
106 
107 	/* The link_sta shouldn't be NULL now, but this is checked in
108 	 * iwl_mld_fw_sta_id_mask
109 	 */
110 	link_sta = link_sta_dereference_check(sta, key->link_id);
111 
112 	sta_id = iwl_mld_fw_sta_id_from_link_sta(mld, link_sta);
113 	if (sta_id < 0)
114 		return 0;
115 
116 	return BIT(sta_id);
117 }
118 
119 static int iwl_mld_add_key_to_fw(struct iwl_mld *mld, u32 sta_mask,
120 				 u32 key_flags, struct ieee80211_key_conf *key)
121 {
122 	struct iwl_sec_key_cmd cmd = {
123 		.action = cpu_to_le32(FW_CTXT_ACTION_ADD),
124 		.u.add.sta_mask = cpu_to_le32(sta_mask),
125 		.u.add.key_id = cpu_to_le32(key->keyidx),
126 		.u.add.key_flags = cpu_to_le32(key_flags),
127 		.u.add.tx_seq = cpu_to_le64(atomic64_read(&key->tx_pn)),
128 	};
129 	bool tkip = key->cipher == WLAN_CIPHER_SUITE_TKIP;
130 	int max_key_len = sizeof(cmd.u.add.key);
131 
132 #ifdef CONFIG_PM_SLEEP
133 	/* If there was a rekey in wowlan, FW already has the key */
134 	if (mld->fw_status.resuming)
135 		return 0;
136 #endif
137 
138 	if (WARN_ON(!sta_mask))
139 		return -EINVAL;
140 
141 	if (WARN_ON(key->keylen > max_key_len))
142 		return -EINVAL;
143 
144 	memcpy(cmd.u.add.key, key->key, key->keylen);
145 
146 	if (tkip) {
147 		memcpy(cmd.u.add.tkip_mic_rx_key,
148 		       key->key + NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY,
149 		       8);
150 		memcpy(cmd.u.add.tkip_mic_tx_key,
151 		       key->key + NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY,
152 		       8);
153 	}
154 
155 	return iwl_mld_send_cmd_pdu(mld, WIDE_ID(DATA_PATH_GROUP, SEC_KEY_CMD),
156 				    &cmd);
157 }
158 
159 static void iwl_mld_remove_key_from_fw(struct iwl_mld *mld, u32 sta_mask,
160 				       u32 key_flags, u32 keyidx)
161 {
162 	struct iwl_sec_key_cmd cmd = {
163 		.action = cpu_to_le32(FW_CTXT_ACTION_REMOVE),
164 		.u.remove.sta_mask = cpu_to_le32(sta_mask),
165 		.u.remove.key_id = cpu_to_le32(keyidx),
166 		.u.remove.key_flags = cpu_to_le32(key_flags),
167 	};
168 
169 #ifdef CONFIG_PM_SLEEP
170 	/* If there was a rekey in wowlan, FW already removed the key */
171 	if (mld->fw_status.resuming)
172 		return;
173 #endif
174 
175 	if (WARN_ON(!sta_mask))
176 		return;
177 
178 	iwl_mld_send_cmd_pdu(mld, WIDE_ID(DATA_PATH_GROUP, SEC_KEY_CMD), &cmd);
179 }
180 
181 void iwl_mld_remove_key(struct iwl_mld *mld, struct ieee80211_vif *vif,
182 			struct ieee80211_sta *sta,
183 			struct ieee80211_key_conf *key)
184 {
185 	u32 sta_mask = iwl_mld_get_key_sta_mask(mld, vif, sta, key);
186 	u32 key_flags = iwl_mld_get_key_flags(mld, vif, sta, key);
187 	struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(vif);
188 
189 	lockdep_assert_wiphy(mld->wiphy);
190 
191 	if (!sta_mask)
192 		return;
193 
194 	if (key->keyidx == 4 || key->keyidx == 5) {
195 		struct iwl_mld_link *mld_link;
196 		unsigned int link_id = 0;
197 
198 		/* set to -1 for non-MLO right now */
199 		if (key->link_id >= 0)
200 			link_id = key->link_id;
201 
202 		mld_link = iwl_mld_link_dereference_check(mld_vif, link_id);
203 		if (WARN_ON(!mld_link))
204 			return;
205 
206 		if (mld_link->igtk == key)
207 			mld_link->igtk = NULL;
208 
209 		mld->num_igtks--;
210 	}
211 
212 	iwl_mld_remove_key_from_fw(mld, sta_mask, key_flags, key->keyidx);
213 
214 	/* no longer in HW */
215 	key->hw_key_idx = STA_KEY_IDX_INVALID;
216 }
217 
218 int iwl_mld_add_key(struct iwl_mld *mld,
219 		    struct ieee80211_vif *vif,
220 		    struct ieee80211_sta *sta,
221 		    struct ieee80211_key_conf *key)
222 {
223 	u32 sta_mask = iwl_mld_get_key_sta_mask(mld, vif, sta, key);
224 	u32 key_flags = iwl_mld_get_key_flags(mld, vif, sta, key);
225 	struct iwl_mld_vif *mld_vif = iwl_mld_vif_from_mac80211(vif);
226 	struct iwl_mld_link *mld_link = NULL;
227 	bool igtk = key->keyidx == 4 || key->keyidx == 5;
228 	int ret;
229 
230 	lockdep_assert_wiphy(mld->wiphy);
231 
232 	if (!sta_mask)
233 		return -EINVAL;
234 
235 	if (igtk) {
236 		if (mld->num_igtks == IWL_MAX_NUM_IGTKS)
237 			return -EOPNOTSUPP;
238 
239 		u8 link_id = 0;
240 
241 		/* set to -1 for non-MLO right now */
242 		if (key->link_id >= 0)
243 			link_id = key->link_id;
244 
245 		mld_link = iwl_mld_link_dereference_check(mld_vif, link_id);
246 
247 		if (WARN_ON(!mld_link))
248 			return -EINVAL;
249 
250 		if (mld_link->igtk) {
251 			IWL_DEBUG_MAC80211(mld, "remove old IGTK %d\n",
252 					   mld_link->igtk->keyidx);
253 			iwl_mld_remove_key(mld, vif, sta, mld_link->igtk);
254 		}
255 
256 		WARN_ON(mld_link->igtk);
257 	}
258 
259 	ret = iwl_mld_add_key_to_fw(mld, sta_mask, key_flags, key);
260 	if (ret)
261 		return ret;
262 
263 	if (mld_link) {
264 		mld_link->igtk = key;
265 		mld->num_igtks++;
266 	}
267 
268 	/* We don't really need this, but need it to be not invalid,
269 	 * so we will know if the key is in fw.
270 	 */
271 	key->hw_key_idx = 0;
272 
273 	return 0;
274 }
275 
276 struct remove_ap_keys_iter_data {
277 	u8 link_id;
278 	struct ieee80211_sta *sta;
279 };
280 
281 static void iwl_mld_remove_ap_keys_iter(struct ieee80211_hw *hw,
282 					struct ieee80211_vif *vif,
283 					struct ieee80211_sta *sta,
284 					struct ieee80211_key_conf *key,
285 					void *_data)
286 {
287 	struct iwl_mld *mld = IWL_MAC80211_GET_MLD(hw);
288 	struct remove_ap_keys_iter_data *data = _data;
289 
290 	if (key->hw_key_idx == STA_KEY_IDX_INVALID)
291 		return;
292 
293 	/* All the pairwise keys should have been removed by now */
294 	if (WARN_ON(sta))
295 		return;
296 
297 	if (key->link_id >= 0 && key->link_id != data->link_id)
298 		return;
299 
300 	iwl_mld_remove_key(mld, vif, data->sta, key);
301 }
302 
303 void iwl_mld_remove_ap_keys(struct iwl_mld *mld, struct ieee80211_vif *vif,
304 			    struct ieee80211_sta *sta, unsigned int link_id)
305 {
306 	struct remove_ap_keys_iter_data iter_data = {
307 		.link_id = link_id,
308 		.sta = sta,
309 	};
310 
311 	if (WARN_ON_ONCE(vif->type != NL80211_IFTYPE_STATION))
312 		return;
313 
314 	ieee80211_iter_keys(mld->hw, vif,
315 			    iwl_mld_remove_ap_keys_iter,
316 			    &iter_data);
317 }
318 
319 struct iwl_mvm_sta_key_update_data {
320 	struct ieee80211_sta *sta;
321 	u32 old_sta_mask;
322 	u32 new_sta_mask;
323 	int err;
324 };
325 
326 static void iwl_mld_update_sta_key_iter(struct ieee80211_hw *hw,
327 					struct ieee80211_vif *vif,
328 					struct ieee80211_sta *sta,
329 					struct ieee80211_key_conf *key,
330 					void *_data)
331 {
332 	struct iwl_mvm_sta_key_update_data *data = _data;
333 	struct iwl_mld *mld = IWL_MAC80211_GET_MLD(hw);
334 	struct iwl_sec_key_cmd cmd = {
335 		.action = cpu_to_le32(FW_CTXT_ACTION_MODIFY),
336 		.u.modify.old_sta_mask = cpu_to_le32(data->old_sta_mask),
337 		.u.modify.new_sta_mask = cpu_to_le32(data->new_sta_mask),
338 		.u.modify.key_id = cpu_to_le32(key->keyidx),
339 		.u.modify.key_flags =
340 			cpu_to_le32(iwl_mld_get_key_flags(mld, vif, sta, key)),
341 	};
342 	int err;
343 
344 	/* only need to do this for pairwise keys (link_id == -1) */
345 	if (sta != data->sta || key->link_id >= 0)
346 		return;
347 
348 	err = iwl_mld_send_cmd_pdu(mld, WIDE_ID(DATA_PATH_GROUP, SEC_KEY_CMD),
349 				   &cmd);
350 
351 	if (err)
352 		data->err = err;
353 }
354 
355 int iwl_mld_update_sta_keys(struct iwl_mld *mld,
356 			    struct ieee80211_vif *vif,
357 			    struct ieee80211_sta *sta,
358 			    u32 old_sta_mask,
359 			    u32 new_sta_mask)
360 {
361 	struct iwl_mvm_sta_key_update_data data = {
362 		.sta = sta,
363 		.old_sta_mask = old_sta_mask,
364 		.new_sta_mask = new_sta_mask,
365 	};
366 
367 	ieee80211_iter_keys(mld->hw, vif, iwl_mld_update_sta_key_iter,
368 			    &data);
369 	return data.err;
370 }
371