1 /******************************************************************************
3 * Copyright (C) 1999-2012 Broadcom Corporation
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:
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 ******************************************************************************/
19 /******************************************************************************
21 * this file contains GATT authentication handling functions
23 ******************************************************************************/
24 #include "bt_target.h"
27 #if BLE_INCLUDED == TRUE
29 #include "bt_common.h"
35 /*******************************************************************************
37 ** Function gatt_sign_data
39 ** Description This function sign the data for write command.
41 ** Returns TRUE if encrypted, otherwise FALSE.
43 *******************************************************************************/
44 static BOOLEAN gatt_sign_data (tGATT_CLCB *p_clcb)
46 tGATT_VALUE *p_attr = (tGATT_VALUE *)p_clcb->p_attr_buf;
47 UINT8 *p_data = NULL, *p;
48 UINT16 payload_size = p_clcb->p_tcb->payload_size;
49 BOOLEAN status = FALSE;
52 /* do not need to mark channel securoty activity for data signing */
53 gatt_set_sec_act(p_clcb->p_tcb, GATT_SEC_OK);
55 p_data = (UINT8 *)osi_malloc(p_attr->len + 3); /* 3 = 2 byte handle + opcode */
58 UINT8_TO_STREAM(p, GATT_SIGN_CMD_WRITE);
59 UINT16_TO_STREAM(p, p_attr->handle);
60 ARRAY_TO_STREAM(p, p_attr->value, p_attr->len);
62 /* sign data length should be attribulte value length plus 2B handle + 1B op code */
63 if ((payload_size - GATT_AUTH_SIGN_LEN - 3) < p_attr->len)
64 p_attr->len = payload_size - GATT_AUTH_SIGN_LEN - 3;
66 p_signature = p_attr->value + p_attr->len;
67 if (BTM_BleDataSignature(p_clcb->p_tcb->peer_bda,
69 (UINT16)(p_attr->len + 3), /* 3 = 2 byte handle + opcode */
71 p_attr->len += BTM_BLE_AUTH_SIGN_LEN;
72 gatt_set_ch_state(p_clcb->p_tcb, GATT_CH_OPEN);
73 gatt_act_write(p_clcb, GATT_SEC_SIGN_DATA);
75 gatt_end_operation(p_clcb, GATT_INTERNAL_ERROR, NULL);
83 /*******************************************************************************
85 ** Function gatt_verify_signature
87 ** Description This function start to verify the sign data when receiving
88 ** the data from peer device.
92 *******************************************************************************/
93 void gatt_verify_signature(tGATT_TCB *p_tcb, BT_HDR *p_buf)
97 UINT8 *p, *p_orig = (UINT8 *)(p_buf + 1) + p_buf->offset;
100 if (p_buf->len < GATT_AUTH_SIGN_LEN + 4) {
101 GATT_TRACE_ERROR("%s: Data length %u less than expected %u",
102 __func__, p_buf->len, GATT_AUTH_SIGN_LEN + 4);
105 cmd_len = p_buf->len - GATT_AUTH_SIGN_LEN + 4;
106 p = p_orig + cmd_len - 4;
107 STREAM_TO_UINT32(counter, p);
109 if (BTM_BleVerifySignature(p_tcb->peer_bda, p_orig, cmd_len, counter, p))
111 STREAM_TO_UINT8(op_code, p_orig);
112 gatt_server_handle_client_req (p_tcb, op_code, (UINT16)(p_buf->len - 1), p_orig);
116 /* if this is a bad signature, assume from attacker, ignore it */
117 GATT_TRACE_ERROR("Signature Verification Failed, data ignored");
122 /*******************************************************************************
124 ** Function gatt_sec_check_complete
126 ** Description security check complete and proceed to data sending action.
130 *******************************************************************************/
131 void gatt_sec_check_complete(BOOLEAN sec_check_ok, tGATT_CLCB *p_clcb, UINT8 sec_act)
133 if (p_clcb && p_clcb->p_tcb &&
134 fixed_queue_is_empty(p_clcb->p_tcb->pending_enc_clcb)) {
135 gatt_set_sec_act(p_clcb->p_tcb, GATT_SEC_NONE);
140 gatt_end_operation(p_clcb, GATT_AUTH_FAIL, NULL);
142 else if (p_clcb->operation == GATTC_OPTYPE_WRITE)
144 gatt_act_write(p_clcb, sec_act);
146 else if (p_clcb->operation == GATTC_OPTYPE_READ)
148 gatt_act_read(p_clcb, p_clcb->counter);
151 /*******************************************************************************
153 ** Function gatt_enc_cmpl_cback
155 ** Description link encryption complete callback.
159 *******************************************************************************/
160 void gatt_enc_cmpl_cback(BD_ADDR bd_addr, tBT_TRANSPORT transport, void *p_ref_data, tBTM_STATUS result)
164 BOOLEAN status = FALSE;
167 GATT_TRACE_DEBUG("gatt_enc_cmpl_cback");
168 if ((p_tcb = gatt_find_tcb_by_addr(bd_addr, transport)) != NULL)
170 if (gatt_get_sec_act(p_tcb) == GATT_SEC_ENC_PENDING)
173 tGATT_PENDING_ENC_CLCB *p_buf =
174 (tGATT_PENDING_ENC_CLCB *)fixed_queue_try_dequeue(p_tcb->pending_enc_clcb);
177 if (result == BTM_SUCCESS)
179 if (gatt_get_sec_act(p_tcb) == GATT_SEC_ENCRYPT_MITM )
181 BTM_GetSecurityFlagsByTransport(bd_addr, &sec_flag, transport);
183 if (sec_flag & BTM_SEC_FLAG_LKEY_AUTHED)
193 gatt_sec_check_complete(status, p_buf->p_clcb, p_tcb->sec_act);
195 /* start all other pending operation in queue */
196 for (size_t count = fixed_queue_length(p_tcb->pending_enc_clcb);
199 p_buf = (tGATT_PENDING_ENC_CLCB *)fixed_queue_try_dequeue(p_tcb->pending_enc_clcb);
202 gatt_security_check_start(p_buf->p_clcb);
211 GATT_TRACE_ERROR("Unknown operation encryption completed");
216 GATT_TRACE_ERROR("enc callback for unknown bd_addr");
220 /*******************************************************************************
222 ** Function gatt_notify_enc_cmpl
224 ** Description link encryption complete notification for all encryption process
225 ** initiated outside GATT.
229 *******************************************************************************/
230 void gatt_notify_enc_cmpl(BD_ADDR bd_addr)
235 if ((p_tcb = gatt_find_tcb_by_addr(bd_addr, BT_TRANSPORT_LE)) != NULL)
237 for (i = 0; i < GATT_MAX_APPS; i++)
239 if (gatt_cb.cl_rcb[i].in_use && gatt_cb.cl_rcb[i].app_cb.p_enc_cmpl_cb)
241 (*gatt_cb.cl_rcb[i].app_cb.p_enc_cmpl_cb)(gatt_cb.cl_rcb[i].gatt_if, bd_addr);
245 if (gatt_get_sec_act(p_tcb) == GATT_SEC_ENC_PENDING)
247 gatt_set_sec_act(p_tcb, GATT_SEC_NONE);
249 size_t count = fixed_queue_length(p_tcb->pending_enc_clcb);
250 for (; count > 0; count--)
252 tGATT_PENDING_ENC_CLCB *p_buf =
253 (tGATT_PENDING_ENC_CLCB *)fixed_queue_try_dequeue(p_tcb->pending_enc_clcb);
256 gatt_security_check_start(p_buf->p_clcb);
266 GATT_TRACE_DEBUG("notify GATT for encryption completion of unknown device");
270 /*******************************************************************************
272 ** Function gatt_set_sec_act
274 ** Description This function set the sec_act in clcb
278 *******************************************************************************/
279 void gatt_set_sec_act(tGATT_TCB *p_tcb, tGATT_SEC_ACTION sec_act)
283 p_tcb->sec_act = sec_act;
286 /*******************************************************************************
288 ** Function gatt_get_sec_act
290 ** Description This function get the sec_act in clcb
294 *******************************************************************************/
295 tGATT_SEC_ACTION gatt_get_sec_act(tGATT_TCB *p_tcb)
297 tGATT_SEC_ACTION sec_act = GATT_SEC_NONE;
300 sec_act = p_tcb->sec_act;
304 /*******************************************************************************
306 ** Function gatt_determine_sec_act
308 ** Description This routine determine the security action based on auth_request and
309 ** current link status
311 ** Returns tGATT_SEC_ACTION security action
313 *******************************************************************************/
314 tGATT_SEC_ACTION gatt_determine_sec_act(tGATT_CLCB *p_clcb )
316 tGATT_SEC_ACTION act = GATT_SEC_OK;
318 tGATT_TCB *p_tcb = p_clcb->p_tcb;
319 tGATT_AUTH_REQ auth_req = p_clcb->auth_req;
320 BOOLEAN is_link_encrypted= FALSE;
321 BOOLEAN is_link_key_known=FALSE;
322 BOOLEAN is_key_mitm=FALSE;
324 tBTM_BLE_SEC_REQ_ACT sec_act = BTM_LE_SEC_NONE;
326 if (auth_req == GATT_AUTH_REQ_NONE )
329 BTM_GetSecurityFlagsByTransport(p_tcb->peer_bda, &sec_flag, p_clcb->p_tcb->transport);
331 btm_ble_link_sec_check(p_tcb->peer_bda, auth_req, &sec_act);
333 /* if a encryption is pending, need to wait */
334 if (sec_act == BTM_BLE_SEC_REQ_ACT_DISCARD &&
335 auth_req != GATT_AUTH_REQ_NONE)
336 return GATT_SEC_ENC_PENDING;
338 if (sec_flag & (BTM_SEC_FLAG_ENCRYPTED| BTM_SEC_FLAG_LKEY_KNOWN))
340 if (sec_flag & BTM_SEC_FLAG_ENCRYPTED)
341 is_link_encrypted = TRUE;
343 is_link_key_known = TRUE;
345 if (sec_flag & BTM_SEC_FLAG_LKEY_AUTHED)
349 /* first check link key upgrade required or not */
352 case GATT_AUTH_REQ_MITM:
353 case GATT_AUTH_REQ_SIGNED_MITM:
355 act = GATT_SEC_ENCRYPT_MITM;
358 case GATT_AUTH_REQ_NO_MITM:
359 case GATT_AUTH_REQ_SIGNED_NO_MITM:
360 if (!is_link_key_known)
361 act = GATT_SEC_ENCRYPT_NO_MITM;
367 /* now check link needs to be encrypted or not if the link key upgrade is not required */
368 if (act == GATT_SEC_OK)
370 if (p_tcb->transport == BT_TRANSPORT_LE &&
371 (p_clcb->operation == GATTC_OPTYPE_WRITE) &&
372 (p_clcb->op_subtype == GATT_WRITE_NO_RSP))
374 /* this is a write command request
375 check data signing required or not */
376 if (!is_link_encrypted)
378 btm_ble_get_enc_key_type(p_tcb->peer_bda, &key_type);
380 if ( (key_type & BTM_LE_KEY_LCSRK) &&
381 ((auth_req == GATT_AUTH_REQ_SIGNED_NO_MITM) ||
382 (auth_req == GATT_AUTH_REQ_SIGNED_MITM)))
384 act = GATT_SEC_SIGN_DATA;
388 act = GATT_SEC_ENCRYPT;
394 if (!is_link_encrypted)
396 act = GATT_SEC_ENCRYPT;
408 /*******************************************************************************
410 ** Function gatt_get_link_encrypt_status
412 ** Description This routine get the encryption status of the specified link
415 ** Returns tGATT_STATUS link encryption status
417 *******************************************************************************/
418 tGATT_STATUS gatt_get_link_encrypt_status(tGATT_TCB *p_tcb)
420 tGATT_STATUS encrypt_status = GATT_NOT_ENCRYPTED;
423 BTM_GetSecurityFlagsByTransport(p_tcb->peer_bda, &sec_flag, p_tcb->transport);
425 if ((sec_flag & BTM_SEC_FLAG_ENCRYPTED) && (sec_flag & BTM_SEC_FLAG_LKEY_KNOWN))
427 encrypt_status = GATT_ENCRYPED_NO_MITM;
428 if (sec_flag & BTM_SEC_FLAG_LKEY_AUTHED)
429 encrypt_status = GATT_ENCRYPED_MITM;
432 GATT_TRACE_DEBUG("gatt_get_link_encrypt_status status=0x%x",encrypt_status);
433 return encrypt_status ;
437 /*******************************************************************************
439 ** Function gatt_convert_sec_action
441 ** Description Convert GATT security action enum into equivalent BTM BLE security action enum
443 ** Returns BOOLEAN TRUE - conversation is successful
445 *******************************************************************************/
446 static BOOLEAN gatt_convert_sec_action(tGATT_SEC_ACTION gatt_sec_act, tBTM_BLE_SEC_ACT *p_btm_sec_act )
448 BOOLEAN status = TRUE;
449 switch (gatt_sec_act)
451 case GATT_SEC_ENCRYPT:
452 *p_btm_sec_act = BTM_BLE_SEC_ENCRYPT;
454 case GATT_SEC_ENCRYPT_NO_MITM:
455 *p_btm_sec_act = BTM_BLE_SEC_ENCRYPT_NO_MITM;
457 case GATT_SEC_ENCRYPT_MITM:
458 *p_btm_sec_act = BTM_BLE_SEC_ENCRYPT_MITM;
467 /*******************************************************************************
469 ** Function gatt_check_enc_req
471 ** Description check link security.
473 ** Returns TRUE if encrypted, otherwise FALSE.
475 *******************************************************************************/
476 BOOLEAN gatt_security_check_start(tGATT_CLCB *p_clcb)
478 tGATT_TCB *p_tcb = p_clcb->p_tcb;
479 tGATT_SEC_ACTION gatt_sec_act;
480 tBTM_BLE_SEC_ACT btm_ble_sec_act;
481 BOOLEAN status = TRUE;
482 tBTM_STATUS btm_status;
483 tGATT_SEC_ACTION sec_act_old = gatt_get_sec_act(p_tcb);
485 gatt_sec_act = gatt_determine_sec_act(p_clcb);
487 if (sec_act_old == GATT_SEC_NONE)
488 gatt_set_sec_act(p_tcb, gatt_sec_act);
490 switch (gatt_sec_act )
492 case GATT_SEC_SIGN_DATA:
493 GATT_TRACE_DEBUG("gatt_security_check_start: Do data signing");
494 gatt_sign_data(p_clcb);
496 case GATT_SEC_ENCRYPT:
497 case GATT_SEC_ENCRYPT_NO_MITM:
498 case GATT_SEC_ENCRYPT_MITM:
499 if (sec_act_old < GATT_SEC_ENCRYPT)
501 GATT_TRACE_DEBUG("gatt_security_check_start: Encrypt now or key upgreade first");
502 gatt_convert_sec_action(gatt_sec_act, &btm_ble_sec_act);
503 btm_status = BTM_SetEncryption(p_tcb->peer_bda, p_tcb->transport,
504 gatt_enc_cmpl_cback, NULL, btm_ble_sec_act);
505 if ( (btm_status != BTM_SUCCESS) && (btm_status != BTM_CMD_STARTED))
507 GATT_TRACE_ERROR("gatt_security_check_start BTM_SetEncryption failed btm_status=%d", btm_status);
512 gatt_add_pending_enc_channel_clcb (p_tcb, p_clcb);
514 case GATT_SEC_ENC_PENDING:
515 gatt_add_pending_enc_channel_clcb (p_tcb, p_clcb);
516 /* wait for link encrypotion to finish */
519 gatt_sec_check_complete(TRUE, p_clcb, gatt_sec_act);
525 gatt_set_sec_act(p_tcb, GATT_SEC_NONE);
526 gatt_set_ch_state(p_tcb, GATT_CH_OPEN);
533 #endif /* BLE_INCLUDED */