| /* |
| Copyright (c) 2011,2012 Intel Corp. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License version 2 and |
| only version 2 as published by the Free Software Foundation. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| */ |
| |
| #include <net/bluetooth/bluetooth.h> |
| #include <net/bluetooth/hci.h> |
| #include <net/bluetooth/hci_core.h> |
| #include <net/bluetooth/a2mp.h> |
| #include <net/bluetooth/amp.h> |
| #include <crypto/hash.h> |
| |
| /* Remote AMP Controllers interface */ |
| void amp_ctrl_get(struct amp_ctrl *ctrl) |
| { |
| BT_DBG("ctrl %p orig refcnt %d", ctrl, |
| atomic_read(&ctrl->kref.refcount)); |
| |
| kref_get(&ctrl->kref); |
| } |
| |
| static void amp_ctrl_destroy(struct kref *kref) |
| { |
| struct amp_ctrl *ctrl = container_of(kref, struct amp_ctrl, kref); |
| |
| BT_DBG("ctrl %p", ctrl); |
| |
| kfree(ctrl->assoc); |
| kfree(ctrl); |
| } |
| |
| int amp_ctrl_put(struct amp_ctrl *ctrl) |
| { |
| BT_DBG("ctrl %p orig refcnt %d", ctrl, |
| atomic_read(&ctrl->kref.refcount)); |
| |
| return kref_put(&ctrl->kref, &_ctrl_destroy); |
| } |
| |
| struct amp_ctrl *amp_ctrl_add(struct amp_mgr *mgr, u8 id) |
| { |
| struct amp_ctrl *ctrl; |
| |
| ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); |
| if (!ctrl) |
| return NULL; |
| |
| kref_init(&ctrl->kref); |
| ctrl->id = id; |
| |
| mutex_lock(&mgr->amp_ctrls_lock); |
| list_add(&ctrl->list, &mgr->amp_ctrls); |
| mutex_unlock(&mgr->amp_ctrls_lock); |
| |
| BT_DBG("mgr %p ctrl %p", mgr, ctrl); |
| |
| return ctrl; |
| } |
| |
| void amp_ctrl_list_flush(struct amp_mgr *mgr) |
| { |
| struct amp_ctrl *ctrl, *n; |
| |
| BT_DBG("mgr %p", mgr); |
| |
| mutex_lock(&mgr->amp_ctrls_lock); |
| list_for_each_entry_safe(ctrl, n, &mgr->amp_ctrls, list) { |
| list_del(&ctrl->list); |
| amp_ctrl_put(ctrl); |
| } |
| mutex_unlock(&mgr->amp_ctrls_lock); |
| } |
| |
| struct amp_ctrl *amp_ctrl_lookup(struct amp_mgr *mgr, u8 id) |
| { |
| struct amp_ctrl *ctrl; |
| |
| BT_DBG("mgr %p id %d", mgr, id); |
| |
| mutex_lock(&mgr->amp_ctrls_lock); |
| list_for_each_entry(ctrl, &mgr->amp_ctrls, list) { |
| if (ctrl->id == id) { |
| amp_ctrl_get(ctrl); |
| mutex_unlock(&mgr->amp_ctrls_lock); |
| return ctrl; |
| } |
| } |
| mutex_unlock(&mgr->amp_ctrls_lock); |
| |
| return NULL; |
| } |
| |
| /* Physical Link interface */ |
| static u8 __next_handle(struct amp_mgr *mgr) |
| { |
| if (++mgr->handle == 0) |
| mgr->handle = 1; |
| |
| return mgr->handle; |
| } |
| |
| struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr, |
| u8 remote_id, bool out) |
| { |
| bdaddr_t *dst = mgr->l2cap_conn->dst; |
| struct hci_conn *hcon; |
| |
| hcon = hci_conn_add(hdev, AMP_LINK, dst); |
| if (!hcon) |
| return NULL; |
| |
| BT_DBG("hcon %p dst %pMR", hcon, dst); |
| |
| hcon->state = BT_CONNECT; |
| hcon->attempt++; |
| hcon->handle = __next_handle(mgr); |
| hcon->remote_id = remote_id; |
| hcon->amp_mgr = mgr; |
| hcon->out = out; |
| |
| return hcon; |
| } |
| |
| /* AMP crypto key generation interface */ |
| static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output) |
| { |
| int ret = 0; |
| struct crypto_shash *tfm; |
| |
| if (!ksize) |
| return -EINVAL; |
| |
| tfm = crypto_alloc_shash("hmac(sha256)", 0, 0); |
| if (IS_ERR(tfm)) { |
| BT_DBG("crypto_alloc_ahash failed: err %ld", PTR_ERR(tfm)); |
| return PTR_ERR(tfm); |
| } |
| |
| ret = crypto_shash_setkey(tfm, key, ksize); |
| if (ret) { |
| BT_DBG("crypto_ahash_setkey failed: err %d", ret); |
| } else { |
| struct { |
| struct shash_desc shash; |
| char ctx[crypto_shash_descsize(tfm)]; |
| } desc; |
| |
| desc.shash.tfm = tfm; |
| desc.shash.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| |
| ret = crypto_shash_digest(&desc.shash, plaintext, psize, |
| output); |
| } |
| |
| crypto_free_shash(tfm); |
| return ret; |
| } |
| |
| int phylink_gen_key(struct hci_conn *conn, u8 *data, u8 *len, u8 *type) |
| { |
| struct hci_dev *hdev = conn->hdev; |
| struct link_key *key; |
| u8 keybuf[HCI_AMP_LINK_KEY_SIZE]; |
| u8 gamp_key[HCI_AMP_LINK_KEY_SIZE]; |
| int err; |
| |
| if (!hci_conn_check_link_mode(conn)) |
| return -EACCES; |
| |
| BT_DBG("conn %p key_type %d", conn, conn->key_type); |
| |
| /* Legacy key */ |
| if (conn->key_type < 3) { |
| BT_ERR("Legacy key type %d", conn->key_type); |
| return -EACCES; |
| } |
| |
| *type = conn->key_type; |
| *len = HCI_AMP_LINK_KEY_SIZE; |
| |
| key = hci_find_link_key(hdev, &conn->dst); |
| if (!key) { |
| BT_DBG("No Link key for conn %p dst %pMR", conn, &conn->dst); |
| return -EACCES; |
| } |
| |
| /* BR/EDR Link Key concatenated together with itself */ |
| memcpy(&keybuf[0], key->val, HCI_LINK_KEY_SIZE); |
| memcpy(&keybuf[HCI_LINK_KEY_SIZE], key->val, HCI_LINK_KEY_SIZE); |
| |
| /* Derive Generic AMP Link Key (gamp) */ |
| err = hmac_sha256(keybuf, HCI_AMP_LINK_KEY_SIZE, "gamp", 4, gamp_key); |
| if (err) { |
| BT_ERR("Could not derive Generic AMP Key: err %d", err); |
| return err; |
| } |
| |
| if (conn->key_type == HCI_LK_DEBUG_COMBINATION) { |
| BT_DBG("Use Generic AMP Key (gamp)"); |
| memcpy(data, gamp_key, HCI_AMP_LINK_KEY_SIZE); |
| return err; |
| } |
| |
| /* Derive Dedicated AMP Link Key: "802b" is 802.11 PAL keyID */ |
| return hmac_sha256(gamp_key, HCI_AMP_LINK_KEY_SIZE, "802b", 4, data); |
| } |
| |
| void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle) |
| { |
| struct hci_cp_read_local_amp_assoc cp; |
| struct amp_assoc *loc_assoc = &hdev->loc_assoc; |
| |
| BT_DBG("%s handle %d", hdev->name, phy_handle); |
| |
| cp.phy_handle = phy_handle; |
| cp.max_len = cpu_to_le16(hdev->amp_assoc_size); |
| cp.len_so_far = cpu_to_le16(loc_assoc->offset); |
| |
| hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp); |
| } |
| |
| void amp_read_loc_assoc(struct hci_dev *hdev, struct amp_mgr *mgr) |
| { |
| struct hci_cp_read_local_amp_assoc cp; |
| |
| memset(&hdev->loc_assoc, 0, sizeof(struct amp_assoc)); |
| memset(&cp, 0, sizeof(cp)); |
| |
| cp.max_len = cpu_to_le16(hdev->amp_assoc_size); |
| |
| mgr->state = READ_LOC_AMP_ASSOC; |
| hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp); |
| } |
| |
| void amp_read_loc_assoc_final_data(struct hci_dev *hdev, |
| struct hci_conn *hcon) |
| { |
| struct hci_cp_read_local_amp_assoc cp; |
| struct amp_mgr *mgr = hcon->amp_mgr; |
| |
| cp.phy_handle = hcon->handle; |
| cp.len_so_far = cpu_to_le16(0); |
| cp.max_len = cpu_to_le16(hdev->amp_assoc_size); |
| |
| mgr->state = READ_LOC_AMP_ASSOC_FINAL; |
| |
| /* Read Local AMP Assoc final link information data */ |
| hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp); |
| } |
| |
| /* Write AMP Assoc data fragments, returns true with last fragment written*/ |
| static bool amp_write_rem_assoc_frag(struct hci_dev *hdev, |
| struct hci_conn *hcon) |
| { |
| struct hci_cp_write_remote_amp_assoc *cp; |
| struct amp_mgr *mgr = hcon->amp_mgr; |
| struct amp_ctrl *ctrl; |
| u16 frag_len, len; |
| |
| ctrl = amp_ctrl_lookup(mgr, hcon->remote_id); |
| if (!ctrl) |
| return false; |
| |
| if (!ctrl->assoc_rem_len) { |
| BT_DBG("all fragments are written"); |
| ctrl->assoc_rem_len = ctrl->assoc_len; |
| ctrl->assoc_len_so_far = 0; |
| |
| amp_ctrl_put(ctrl); |
| return true; |
| } |
| |
| frag_len = min_t(u16, 248, ctrl->assoc_rem_len); |
| len = frag_len + sizeof(*cp); |
| |
| cp = kzalloc(len, GFP_KERNEL); |
| if (!cp) { |
| amp_ctrl_put(ctrl); |
| return false; |
| } |
| |
| BT_DBG("hcon %p ctrl %p frag_len %u assoc_len %u rem_len %u", |
| hcon, ctrl, frag_len, ctrl->assoc_len, ctrl->assoc_rem_len); |
| |
| cp->phy_handle = hcon->handle; |
| cp->len_so_far = cpu_to_le16(ctrl->assoc_len_so_far); |
| cp->rem_len = cpu_to_le16(ctrl->assoc_rem_len); |
| memcpy(cp->frag, ctrl->assoc, frag_len); |
| |
| ctrl->assoc_len_so_far += frag_len; |
| ctrl->assoc_rem_len -= frag_len; |
| |
| amp_ctrl_put(ctrl); |
| |
| hci_send_cmd(hdev, HCI_OP_WRITE_REMOTE_AMP_ASSOC, len, cp); |
| |
| kfree(cp); |
| |
| return false; |
| } |
| |
| void amp_write_rem_assoc_continue(struct hci_dev *hdev, u8 handle) |
| { |
| struct hci_conn *hcon; |
| |
| BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle); |
| |
| hcon = hci_conn_hash_lookup_handle(hdev, handle); |
| if (!hcon) |
| return; |
| |
| amp_write_rem_assoc_frag(hdev, hcon); |
| } |
| |
| void amp_write_remote_assoc(struct hci_dev *hdev, u8 handle) |
| { |
| struct hci_conn *hcon; |
| |
| BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle); |
| |
| hcon = hci_conn_hash_lookup_handle(hdev, handle); |
| if (!hcon) |
| return; |
| |
| BT_DBG("%s phy handle 0x%2.2x hcon %p", hdev->name, handle, hcon); |
| |
| amp_write_rem_assoc_frag(hdev, hcon); |
| } |
| |
| void amp_create_phylink(struct hci_dev *hdev, struct amp_mgr *mgr, |
| struct hci_conn *hcon) |
| { |
| struct hci_cp_create_phy_link cp; |
| |
| cp.phy_handle = hcon->handle; |
| |
| BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon, |
| hcon->handle); |
| |
| if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len, |
| &cp.key_type)) { |
| BT_DBG("Cannot create link key"); |
| return; |
| } |
| |
| hci_send_cmd(hdev, HCI_OP_CREATE_PHY_LINK, sizeof(cp), &cp); |
| } |
| |
| void amp_accept_phylink(struct hci_dev *hdev, struct amp_mgr *mgr, |
| struct hci_conn *hcon) |
| { |
| struct hci_cp_accept_phy_link cp; |
| |
| cp.phy_handle = hcon->handle; |
| |
| BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon, |
| hcon->handle); |
| |
| if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len, |
| &cp.key_type)) { |
| BT_DBG("Cannot create link key"); |
| return; |
| } |
| |
| hci_send_cmd(hdev, HCI_OP_ACCEPT_PHY_LINK, sizeof(cp), &cp); |
| } |