/* 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 <crypto/hash.h> #include "a2mp.h" #include "amp.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->hcon->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 = amp_mgr_get(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); set_bit(READ_LOC_AMP_ASSOC, &mgr->state); 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); set_bit(READ_LOC_AMP_ASSOC_FINAL, &mgr->state); /* 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; /* Send A2MP create phylink rsp when all fragments are written */ if (amp_write_rem_assoc_frag(hdev, hcon)) a2mp_send_create_phy_link_rsp(hdev, 0); } 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); } void amp_physical_cfm(struct hci_conn *bredr_hcon, struct hci_conn *hs_hcon) { struct hci_dev *bredr_hdev = hci_dev_hold(bredr_hcon->hdev); struct amp_mgr *mgr = hs_hcon->amp_mgr; struct l2cap_chan *bredr_chan; BT_DBG("bredr_hcon %p hs_hcon %p mgr %p", bredr_hcon, hs_hcon, mgr); if (!bredr_hdev || !mgr || !mgr->bredr_chan) return; bredr_chan = mgr->bredr_chan; l2cap_chan_lock(bredr_chan); set_bit(FLAG_EFS_ENABLE, &bredr_chan->flags); bredr_chan->remote_amp_id = hs_hcon->remote_id; bredr_chan->local_amp_id = hs_hcon->hdev->id; bredr_chan->hs_hcon = hs_hcon; bredr_chan->conn->mtu = hs_hcon->hdev->block_mtu; __l2cap_physical_cfm(bredr_chan, 0); l2cap_chan_unlock(bredr_chan); hci_dev_put(bredr_hdev); } void amp_create_logical_link(struct l2cap_chan *chan) { struct hci_conn *hs_hcon = chan->hs_hcon; struct hci_cp_create_accept_logical_link cp; struct hci_dev *hdev; BT_DBG("chan %p hs_hcon %p dst %pMR", chan, hs_hcon, &chan->conn->hcon->dst); if (!hs_hcon) return; hdev = hci_dev_hold(chan->hs_hcon->hdev); if (!hdev) return; cp.phy_handle = hs_hcon->handle; cp.tx_flow_spec.id = chan->local_id; cp.tx_flow_spec.stype = chan->local_stype; cp.tx_flow_spec.msdu = cpu_to_le16(chan->local_msdu); cp.tx_flow_spec.sdu_itime = cpu_to_le32(chan->local_sdu_itime); cp.tx_flow_spec.acc_lat = cpu_to_le32(chan->local_acc_lat); cp.tx_flow_spec.flush_to = cpu_to_le32(chan->local_flush_to); cp.rx_flow_spec.id = chan->remote_id; cp.rx_flow_spec.stype = chan->remote_stype; cp.rx_flow_spec.msdu = cpu_to_le16(chan->remote_msdu); cp.rx_flow_spec.sdu_itime = cpu_to_le32(chan->remote_sdu_itime); cp.rx_flow_spec.acc_lat = cpu_to_le32(chan->remote_acc_lat); cp.rx_flow_spec.flush_to = cpu_to_le32(chan->remote_flush_to); if (hs_hcon->out) hci_send_cmd(hdev, HCI_OP_CREATE_LOGICAL_LINK, sizeof(cp), &cp); else hci_send_cmd(hdev, HCI_OP_ACCEPT_LOGICAL_LINK, sizeof(cp), &cp); hci_dev_put(hdev); } void amp_disconnect_logical_link(struct hci_chan *hchan) { struct hci_conn *hcon = hchan->conn; struct hci_cp_disconn_logical_link cp; if (hcon->state != BT_CONNECTED) { BT_DBG("hchan %p not connected", hchan); return; } cp.log_handle = cpu_to_le16(hchan->handle); hci_send_cmd(hcon->hdev, HCI_OP_DISCONN_LOGICAL_LINK, sizeof(cp), &cp); } void amp_destroy_logical_link(struct hci_chan *hchan, u8 reason) { BT_DBG("hchan %p", hchan); hci_chan_del(hchan); }