1 /******************************************************************************
2 *
3 * Copyright (C) 1999-2012 Broadcom Corporation
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at:
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 ******************************************************************************/
18
19 /******************************************************************************
20 *
21 * This file contains functions for the SMP L2Cap interface
22 *
23 ******************************************************************************/
24
25 #include "bt_target.h"
26
27 #include <string.h>
28 #include "btm_ble_api.h"
29 #include "l2c_api.h"
30
31 #include "smp_int.h"
32
33 static void smp_tx_complete_callback(uint16_t cid, uint16_t num_pkt);
34
35 static void smp_connect_callback(uint16_t channel, const RawAddress& bd_addr,
36 bool connected, uint16_t reason,
37 tBT_TRANSPORT transport);
38 static void smp_data_received(uint16_t channel, const RawAddress& bd_addr,
39 BT_HDR* p_buf);
40
41 static void smp_br_connect_callback(uint16_t channel, const RawAddress& bd_addr,
42 bool connected, uint16_t reason,
43 tBT_TRANSPORT transport);
44 static void smp_br_data_received(uint16_t channel, const RawAddress& bd_addr,
45 BT_HDR* p_buf);
46
47 /*******************************************************************************
48 *
49 * Function smp_l2cap_if_init
50 *
51 * Description This function is called during the SMP task startup
52 * to register interface functions with L2CAP.
53 *
54 ******************************************************************************/
smp_l2cap_if_init(void)55 void smp_l2cap_if_init(void) {
56 tL2CAP_FIXED_CHNL_REG fixed_reg;
57 SMP_TRACE_EVENT("SMDBG l2c %s", __func__);
58 fixed_reg.fixed_chnl_opts.mode = L2CAP_FCR_BASIC_MODE;
59 fixed_reg.fixed_chnl_opts.max_transmit = 0;
60 fixed_reg.fixed_chnl_opts.rtrans_tout = 0;
61 fixed_reg.fixed_chnl_opts.mon_tout = 0;
62 fixed_reg.fixed_chnl_opts.mps = 0;
63 fixed_reg.fixed_chnl_opts.tx_win_sz = 0;
64
65 fixed_reg.pL2CA_FixedConn_Cb = smp_connect_callback;
66 fixed_reg.pL2CA_FixedData_Cb = smp_data_received;
67 fixed_reg.pL2CA_FixedTxComplete_Cb = smp_tx_complete_callback;
68
69 fixed_reg.pL2CA_FixedCong_Cb =
70 NULL; /* do not handle congestion on this channel */
71 fixed_reg.default_idle_tout =
72 60; /* set 60 seconds timeout, 0xffff default idle timeout */
73
74 L2CA_RegisterFixedChannel(L2CAP_SMP_CID, &fixed_reg);
75
76 fixed_reg.pL2CA_FixedConn_Cb = smp_br_connect_callback;
77 fixed_reg.pL2CA_FixedData_Cb = smp_br_data_received;
78
79 L2CA_RegisterFixedChannel(L2CAP_SMP_BR_CID, &fixed_reg);
80 }
81
82 /*******************************************************************************
83 *
84 * Function smp_connect_callback
85 *
86 * Description This callback function is called by L2CAP to indicate that
87 * SMP channel is
88 * connected (conn = true)/disconnected (conn = false).
89 *
90 ******************************************************************************/
smp_connect_callback(uint16_t channel,const RawAddress & bd_addr,bool connected,uint16_t reason,tBT_TRANSPORT transport)91 static void smp_connect_callback(uint16_t channel, const RawAddress& bd_addr,
92 bool connected, uint16_t reason,
93 tBT_TRANSPORT transport) {
94 tSMP_CB* p_cb = &smp_cb;
95 tSMP_INT_DATA int_data;
96
97 SMP_TRACE_EVENT("SMDBG l2c %s", __func__);
98
99 if (transport == BT_TRANSPORT_BR_EDR || bd_addr.IsEmpty()) return;
100
101 if (bd_addr == p_cb->pairing_bda) {
102 VLOG(2) << __func__ << " for pairing BDA: " << bd_addr
103 << " Event: " << ((connected) ? "connected" : "disconnected");
104
105 if (connected) {
106 if (!p_cb->connect_initialized) {
107 p_cb->connect_initialized = true;
108 /* initiating connection established */
109 p_cb->role = L2CA_GetBleConnRole(bd_addr);
110
111 /* initialize local i/r key to be default keys */
112 p_cb->local_r_key = p_cb->local_i_key = SMP_SEC_DEFAULT_KEY;
113 p_cb->loc_auth_req = p_cb->peer_auth_req = SMP_DEFAULT_AUTH_REQ;
114 p_cb->cb_evt = SMP_IO_CAP_REQ_EVT;
115 smp_sm_event(p_cb, SMP_L2CAP_CONN_EVT, NULL);
116 }
117 } else {
118 int_data.reason = reason;
119 /* Disconnected while doing security */
120 smp_sm_event(p_cb, SMP_L2CAP_DISCONN_EVT, &int_data);
121 }
122 }
123 }
124
125 /*******************************************************************************
126 *
127 * Function smp_data_received
128 *
129 * Description This function is called when data is received from L2CAP on
130 * SMP channel.
131 *
132 *
133 * Returns void
134 *
135 ******************************************************************************/
smp_data_received(uint16_t channel,const RawAddress & bd_addr,BT_HDR * p_buf)136 static void smp_data_received(uint16_t channel, const RawAddress& bd_addr,
137 BT_HDR* p_buf) {
138 tSMP_CB* p_cb = &smp_cb;
139 uint8_t* p = (uint8_t*)(p_buf + 1) + p_buf->offset;
140 uint8_t cmd;
141 SMP_TRACE_EVENT("SMDBG l2c %s", __func__);
142
143 STREAM_TO_UINT8(cmd, p);
144
145 /* sanity check */
146 if ((SMP_OPCODE_MAX < cmd) || (SMP_OPCODE_MIN > cmd)) {
147 SMP_TRACE_WARNING("Ignore received command with RESERVED code 0x%02x", cmd);
148 osi_free(p_buf);
149 return;
150 }
151
152 /* reject the pairing request if there is an on-going SMP pairing */
153 if (SMP_OPCODE_PAIRING_REQ == cmd || SMP_OPCODE_SEC_REQ == cmd) {
154 if ((p_cb->state == SMP_STATE_IDLE) &&
155 (p_cb->br_state == SMP_BR_STATE_IDLE) &&
156 !(p_cb->flags & SMP_PAIR_FLAGS_WE_STARTED_DD)) {
157 p_cb->role = L2CA_GetBleConnRole(bd_addr);
158 p_cb->pairing_bda = bd_addr;
159 } else if (bd_addr != p_cb->pairing_bda) {
160 osi_free(p_buf);
161 smp_reject_unexpected_pairing_command(bd_addr);
162 return;
163 }
164 /* else, out of state pairing request/security request received, passed into
165 * SM */
166 }
167
168 if (bd_addr == p_cb->pairing_bda) {
169 alarm_set_on_mloop(p_cb->smp_rsp_timer_ent, SMP_WAIT_FOR_RSP_TIMEOUT_MS,
170 smp_rsp_timeout, NULL);
171
172 if (cmd == SMP_OPCODE_CONFIRM) {
173 SMP_TRACE_DEBUG(
174 "in %s cmd = 0x%02x, peer_auth_req = 0x%02x,"
175 "loc_auth_req = 0x%02x",
176 __func__, cmd, p_cb->peer_auth_req, p_cb->loc_auth_req);
177
178 if ((p_cb->peer_auth_req & SMP_SC_SUPPORT_BIT) &&
179 (p_cb->loc_auth_req & SMP_SC_SUPPORT_BIT)) {
180 cmd = SMP_OPCODE_PAIR_COMMITM;
181 }
182 }
183
184 p_cb->rcvd_cmd_code = cmd;
185 p_cb->rcvd_cmd_len = (uint8_t)p_buf->len;
186 smp_sm_event(p_cb, cmd, p);
187 }
188
189 osi_free(p_buf);
190 }
191
192 /*******************************************************************************
193 *
194 * Function smp_tx_complete_callback
195 *
196 * Description SMP channel tx complete callback
197 *
198 ******************************************************************************/
smp_tx_complete_callback(uint16_t cid,uint16_t num_pkt)199 static void smp_tx_complete_callback(uint16_t cid, uint16_t num_pkt) {
200 tSMP_CB* p_cb = &smp_cb;
201
202 if (p_cb->total_tx_unacked >= num_pkt)
203 p_cb->total_tx_unacked -= num_pkt;
204 else
205 SMP_TRACE_ERROR("Unexpected %s: num_pkt = %d", __func__, num_pkt);
206
207 uint8_t reason = SMP_SUCCESS;
208 if (p_cb->total_tx_unacked == 0 && p_cb->wait_for_authorization_complete) {
209 if (cid == L2CAP_SMP_CID)
210 smp_sm_event(p_cb, SMP_AUTH_CMPL_EVT, &reason);
211 else
212 smp_br_state_machine_event(p_cb, SMP_BR_AUTH_CMPL_EVT, &reason);
213 }
214 }
215
216 /*******************************************************************************
217 *
218 * Function smp_br_connect_callback
219 *
220 * Description This callback function is called by L2CAP to indicate that
221 * SMP BR channel is
222 * connected (conn = true)/disconnected (conn = false).
223 *
224 ******************************************************************************/
smp_br_connect_callback(uint16_t channel,const RawAddress & bd_addr,bool connected,uint16_t reason,tBT_TRANSPORT transport)225 static void smp_br_connect_callback(uint16_t channel, const RawAddress& bd_addr,
226 bool connected, uint16_t reason,
227 tBT_TRANSPORT transport) {
228 tSMP_CB* p_cb = &smp_cb;
229 tSMP_INT_DATA int_data;
230
231 SMP_TRACE_EVENT("%s", __func__);
232
233 if (transport != BT_TRANSPORT_BR_EDR) {
234 SMP_TRACE_WARNING("%s is called on unexpected transport %d", __func__,
235 transport);
236 return;
237 }
238
239 if (bd_addr != p_cb->pairing_bda) return;
240
241 VLOG(1) << __func__ << " for pairing BDA: " << bd_addr
242 << " Event: " << ((connected) ? "connected" : "disconnected");
243
244 if (connected) {
245 if (!p_cb->connect_initialized) {
246 p_cb->connect_initialized = true;
247 /* initialize local i/r key to be default keys */
248 p_cb->local_r_key = p_cb->local_i_key = SMP_BR_SEC_DEFAULT_KEY;
249 p_cb->loc_auth_req = p_cb->peer_auth_req = 0;
250 p_cb->cb_evt = SMP_BR_KEYS_REQ_EVT;
251 smp_br_state_machine_event(p_cb, SMP_BR_L2CAP_CONN_EVT, NULL);
252 }
253 } else {
254 int_data.reason = reason;
255 /* Disconnected while doing security */
256 smp_br_state_machine_event(p_cb, SMP_BR_L2CAP_DISCONN_EVT, &int_data);
257 }
258 }
259
260 /*******************************************************************************
261 *
262 * Function smp_br_data_received
263 *
264 * Description This function is called when data is received from L2CAP on
265 * SMP BR channel.
266 *
267 * Returns void
268 *
269 ******************************************************************************/
smp_br_data_received(uint16_t channel,const RawAddress & bd_addr,BT_HDR * p_buf)270 static void smp_br_data_received(uint16_t channel, const RawAddress& bd_addr,
271 BT_HDR* p_buf) {
272 tSMP_CB* p_cb = &smp_cb;
273 uint8_t* p = (uint8_t*)(p_buf + 1) + p_buf->offset;
274 uint8_t cmd;
275 SMP_TRACE_EVENT("SMDBG l2c %s", __func__);
276
277 STREAM_TO_UINT8(cmd, p);
278
279 /* sanity check */
280 if ((SMP_OPCODE_MAX < cmd) || (SMP_OPCODE_MIN > cmd)) {
281 SMP_TRACE_WARNING("Ignore received command with RESERVED code 0x%02x", cmd);
282 osi_free(p_buf);
283 return;
284 }
285
286 /* reject the pairing request if there is an on-going SMP pairing */
287 if (SMP_OPCODE_PAIRING_REQ == cmd) {
288 if ((p_cb->state == SMP_STATE_IDLE) &&
289 (p_cb->br_state == SMP_BR_STATE_IDLE)) {
290 p_cb->role = HCI_ROLE_SLAVE;
291 p_cb->smp_over_br = true;
292 p_cb->pairing_bda = bd_addr;
293 } else if (bd_addr != p_cb->pairing_bda) {
294 osi_free(p_buf);
295 smp_reject_unexpected_pairing_command(bd_addr);
296 return;
297 }
298 /* else, out of state pairing request received, passed into State Machine */
299 }
300
301 if (bd_addr == p_cb->pairing_bda) {
302 alarm_set_on_mloop(p_cb->smp_rsp_timer_ent, SMP_WAIT_FOR_RSP_TIMEOUT_MS,
303 smp_rsp_timeout, NULL);
304
305 p_cb->rcvd_cmd_code = cmd;
306 p_cb->rcvd_cmd_len = (uint8_t)p_buf->len;
307 smp_br_state_machine_event(p_cb, cmd, p);
308 }
309
310 osi_free(p_buf);
311 }
312