2 Copyright (c) 2011,2012 Intel Corp.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License version 2 and
6 only version 2 as published by the Free Software Foundation.
8 This program is distributed in the hope that it will be useful,
9 but WITHOUT ANY WARRANTY; without even the implied warranty of
10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 GNU General Public License for more details.
14 #include <net/bluetooth/bluetooth.h>
15 #include <net/bluetooth/hci.h>
16 #include <net/bluetooth/hci_core.h>
17 #include <net/bluetooth/a2mp.h>
18 #include <net/bluetooth/amp.h>
19 #include <crypto/hash.h>
21 /* Remote AMP Controllers interface */
22 void amp_ctrl_get(struct amp_ctrl *ctrl)
24 BT_DBG("ctrl %p orig refcnt %d", ctrl,
25 atomic_read(&ctrl->kref.refcount));
27 kref_get(&ctrl->kref);
30 static void amp_ctrl_destroy(struct kref *kref)
32 struct amp_ctrl *ctrl = container_of(kref, struct amp_ctrl, kref);
34 BT_DBG("ctrl %p", ctrl);
40 int amp_ctrl_put(struct amp_ctrl *ctrl)
42 BT_DBG("ctrl %p orig refcnt %d", ctrl,
43 atomic_read(&ctrl->kref.refcount));
45 return kref_put(&ctrl->kref, &_ctrl_destroy);
48 struct amp_ctrl *amp_ctrl_add(struct amp_mgr *mgr, u8 id)
50 struct amp_ctrl *ctrl;
52 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
56 kref_init(&ctrl->kref);
59 mutex_lock(&mgr->amp_ctrls_lock);
60 list_add(&ctrl->list, &mgr->amp_ctrls);
61 mutex_unlock(&mgr->amp_ctrls_lock);
63 BT_DBG("mgr %p ctrl %p", mgr, ctrl);
68 void amp_ctrl_list_flush(struct amp_mgr *mgr)
70 struct amp_ctrl *ctrl, *n;
72 BT_DBG("mgr %p", mgr);
74 mutex_lock(&mgr->amp_ctrls_lock);
75 list_for_each_entry_safe(ctrl, n, &mgr->amp_ctrls, list) {
76 list_del(&ctrl->list);
79 mutex_unlock(&mgr->amp_ctrls_lock);
82 struct amp_ctrl *amp_ctrl_lookup(struct amp_mgr *mgr, u8 id)
84 struct amp_ctrl *ctrl;
86 BT_DBG("mgr %p id %d", mgr, id);
88 mutex_lock(&mgr->amp_ctrls_lock);
89 list_for_each_entry(ctrl, &mgr->amp_ctrls, list) {
92 mutex_unlock(&mgr->amp_ctrls_lock);
96 mutex_unlock(&mgr->amp_ctrls_lock);
101 /* Physical Link interface */
102 static u8 __next_handle(struct amp_mgr *mgr)
104 if (++mgr->handle == 0)
110 struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr,
113 bdaddr_t *dst = mgr->l2cap_conn->dst;
114 struct hci_conn *hcon;
116 hcon = hci_conn_add(hdev, AMP_LINK, dst);
120 hcon->state = BT_CONNECT;
123 hcon->handle = __next_handle(mgr);
124 hcon->remote_id = remote_id;
130 /* AMP crypto key generation interface */
131 static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output)
134 struct crypto_shash *tfm;
139 tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
141 BT_DBG("crypto_alloc_ahash failed: err %ld", PTR_ERR(tfm));
145 ret = crypto_shash_setkey(tfm, key, ksize);
147 BT_DBG("crypto_ahash_setkey failed: err %d", ret);
150 struct shash_desc shash;
151 char ctx[crypto_shash_descsize(tfm)];
154 desc.shash.tfm = tfm;
155 desc.shash.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
157 ret = crypto_shash_digest(&desc.shash, plaintext, psize,
161 crypto_free_shash(tfm);
165 int phylink_gen_key(struct hci_conn *conn, u8 *data, u8 *len, u8 *type)
167 struct hci_dev *hdev = conn->hdev;
168 struct link_key *key;
169 u8 keybuf[HCI_AMP_LINK_KEY_SIZE];
170 u8 gamp_key[HCI_AMP_LINK_KEY_SIZE];
173 if (!hci_conn_check_link_mode(conn))
176 BT_DBG("conn %p key_type %d", conn, conn->key_type);
179 if (conn->key_type < 3) {
180 BT_ERR("Legacy key type %d", conn->key_type);
184 *type = conn->key_type;
185 *len = HCI_AMP_LINK_KEY_SIZE;
187 key = hci_find_link_key(hdev, &conn->dst);
189 BT_DBG("No Link key for conn %p dst %pMR", conn, &conn->dst);
193 /* BR/EDR Link Key concatenated together with itself */
194 memcpy(&keybuf[0], key->val, HCI_LINK_KEY_SIZE);
195 memcpy(&keybuf[HCI_LINK_KEY_SIZE], key->val, HCI_LINK_KEY_SIZE);
197 /* Derive Generic AMP Link Key (gamp) */
198 err = hmac_sha256(keybuf, HCI_AMP_LINK_KEY_SIZE, "gamp", 4, gamp_key);
200 BT_ERR("Could not derive Generic AMP Key: err %d", err);
204 if (conn->key_type == HCI_LK_DEBUG_COMBINATION) {
205 BT_DBG("Use Generic AMP Key (gamp)");
206 memcpy(data, gamp_key, HCI_AMP_LINK_KEY_SIZE);
210 /* Derive Dedicated AMP Link Key: "802b" is 802.11 PAL keyID */
211 return hmac_sha256(gamp_key, HCI_AMP_LINK_KEY_SIZE, "802b", 4, data);
214 void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle)
216 struct hci_cp_read_local_amp_assoc cp;
217 struct amp_assoc *loc_assoc = &hdev->loc_assoc;
219 BT_DBG("%s handle %d", hdev->name, phy_handle);
221 cp.phy_handle = phy_handle;
222 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
223 cp.len_so_far = cpu_to_le16(loc_assoc->offset);
225 hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
228 void amp_read_loc_assoc(struct hci_dev *hdev, struct amp_mgr *mgr)
230 struct hci_cp_read_local_amp_assoc cp;
232 memset(&hdev->loc_assoc, 0, sizeof(struct amp_assoc));
233 memset(&cp, 0, sizeof(cp));
235 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
237 mgr->state = READ_LOC_AMP_ASSOC;
238 hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
241 void amp_read_loc_assoc_final_data(struct hci_dev *hdev,
242 struct hci_conn *hcon)
244 struct hci_cp_read_local_amp_assoc cp;
245 struct amp_mgr *mgr = hcon->amp_mgr;
247 cp.phy_handle = hcon->handle;
248 cp.len_so_far = cpu_to_le16(0);
249 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
251 mgr->state = READ_LOC_AMP_ASSOC_FINAL;
253 /* Read Local AMP Assoc final link information data */
254 hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
257 /* Write AMP Assoc data fragments, returns true with last fragment written*/
258 static bool amp_write_rem_assoc_frag(struct hci_dev *hdev,
259 struct hci_conn *hcon)
261 struct hci_cp_write_remote_amp_assoc *cp;
262 struct amp_mgr *mgr = hcon->amp_mgr;
263 struct amp_ctrl *ctrl;
266 ctrl = amp_ctrl_lookup(mgr, hcon->remote_id);
270 if (!ctrl->assoc_rem_len) {
271 BT_DBG("all fragments are written");
272 ctrl->assoc_rem_len = ctrl->assoc_len;
273 ctrl->assoc_len_so_far = 0;
279 frag_len = min_t(u16, 248, ctrl->assoc_rem_len);
280 len = frag_len + sizeof(*cp);
282 cp = kzalloc(len, GFP_KERNEL);
288 BT_DBG("hcon %p ctrl %p frag_len %u assoc_len %u rem_len %u",
289 hcon, ctrl, frag_len, ctrl->assoc_len, ctrl->assoc_rem_len);
291 cp->phy_handle = hcon->handle;
292 cp->len_so_far = cpu_to_le16(ctrl->assoc_len_so_far);
293 cp->rem_len = cpu_to_le16(ctrl->assoc_rem_len);
294 memcpy(cp->frag, ctrl->assoc, frag_len);
296 ctrl->assoc_len_so_far += frag_len;
297 ctrl->assoc_rem_len -= frag_len;
301 hci_send_cmd(hdev, HCI_OP_WRITE_REMOTE_AMP_ASSOC, len, cp);
308 void amp_write_rem_assoc_continue(struct hci_dev *hdev, u8 handle)
310 struct hci_conn *hcon;
312 BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
314 hcon = hci_conn_hash_lookup_handle(hdev, handle);
318 amp_write_rem_assoc_frag(hdev, hcon);
321 void amp_write_remote_assoc(struct hci_dev *hdev, u8 handle)
323 struct hci_conn *hcon;
325 BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
327 hcon = hci_conn_hash_lookup_handle(hdev, handle);
331 BT_DBG("%s phy handle 0x%2.2x hcon %p", hdev->name, handle, hcon);
333 amp_write_rem_assoc_frag(hdev, hcon);
336 void amp_create_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
337 struct hci_conn *hcon)
339 struct hci_cp_create_phy_link cp;
341 cp.phy_handle = hcon->handle;
343 BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
346 if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
348 BT_DBG("Cannot create link key");
352 hci_send_cmd(hdev, HCI_OP_CREATE_PHY_LINK, sizeof(cp), &cp);
355 void amp_accept_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
356 struct hci_conn *hcon)
358 struct hci_cp_accept_phy_link cp;
360 cp.phy_handle = hcon->handle;
362 BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
365 if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
367 BT_DBG("Cannot create link key");
371 hci_send_cmd(hdev, HCI_OP_ACCEPT_PHY_LINK, sizeof(cp), &cp);