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|
/*
*
* BlueZ - Bluetooth protocol stack for Linux
*
* Copyright (C) 2001-2002 Nokia Corporation
* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
* Copyright (C) 2002-2008 Marcel Holtmann <marcel@holtmann.org>
* Copyright (C) 2002-2003 Stephen Crane <steve.crane@rococosoft.com>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <sys/socket.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/l2cap.h>
#include <bluetooth/sdp.h>
#include <bluetooth/sdp_lib.h>
#include <netinet/in.h>
#include "sdpd.h"
#include "logging.h"
#define MIN(x, y) ((x) < (y))? (x): (y)
/* Additional values for checking datatype (not in spec) */
#define SDP_TYPE_UUID 0xfe
#define SDP_TYPE_ANY 0xff
/*
* Generic data element sequence extractor. Builds
* a list whose elements are those found in the
* sequence. The data type of elements found in the
* sequence is returned in the reference pDataType
*/
static int extract_des(uint8_t *buf, int len, sdp_list_t **svcReqSeq, uint8_t *pDataType, uint8_t expectedType)
{
uint8_t seqType;
int scanned, data_size = 0;
short numberOfElements = 0;
int seqlen = 0;
sdp_list_t *pSeq = NULL;
uint8_t dataType;
int status = 0;
const uint8_t *p;
int bufsize;
scanned = sdp_extract_seqtype_safe(buf, len, &seqType, &data_size);
debug("Seq type : %d", seqType);
if (!scanned || (seqType != SDP_SEQ8 && seqType != SDP_SEQ16)) {
error("Unknown seq type");
return -1;
}
p = buf + scanned;
bufsize = len - scanned;
debug("Data size : %d", data_size);
for (;;) {
char *pElem = NULL;
int localSeqLength = 0;
if (bufsize < sizeof(uint8_t)) {
debug("->Unexpected end of buffer");
return -1;
}
dataType = *(uint8_t *)p;
debug("Data type: 0x%02x", dataType);
if (expectedType == SDP_TYPE_UUID) {
if (dataType != SDP_UUID16 && dataType != SDP_UUID32 && dataType != SDP_UUID128) {
debug("->Unexpected Data type (expected UUID_ANY)");
return -1;
}
} else if (expectedType != SDP_TYPE_ANY && dataType != expectedType) {
debug("->Unexpected Data type (expected 0x%02x)", expectedType);
return -1;
}
switch (dataType) {
case SDP_UINT16:
p += sizeof(uint8_t);
seqlen += sizeof(uint8_t);
bufsize -= sizeof(uint8_t);
if (bufsize < sizeof(uint16_t)) {
debug("->Unexpected end of buffer");
return -1;
}
pElem = malloc(sizeof(uint16_t));
bt_put_unaligned(ntohs(bt_get_unaligned((uint16_t *)p)), (uint16_t *)pElem);
p += sizeof(uint16_t);
seqlen += sizeof(uint16_t);
bufsize -= sizeof(uint16_t);
break;
case SDP_UINT32:
p += sizeof(uint8_t);
seqlen += sizeof(uint8_t);
bufsize -= sizeof(uint8_t);
if (bufsize < (int)sizeof(uint32_t)) {
debug("->Unexpected end of buffer");
return -1;
}
pElem = malloc(sizeof(uint32_t));
bt_put_unaligned(ntohl(bt_get_unaligned((uint32_t *)p)), (uint32_t *)pElem);
p += sizeof(uint32_t);
seqlen += sizeof(uint32_t);
bufsize -= sizeof(uint32_t);
break;
case SDP_UUID16:
case SDP_UUID32:
case SDP_UUID128:
pElem = malloc(sizeof(uuid_t));
status = sdp_uuid_extract_safe(p, bufsize, (uuid_t *) pElem, &localSeqLength);
if (status == 0) {
seqlen += localSeqLength;
p += localSeqLength;
bufsize -= localSeqLength;
}
break;
default:
return -1;
}
if (status == 0) {
pSeq = sdp_list_append(pSeq, pElem);
numberOfElements++;
debug("No of elements : %d", numberOfElements);
if (seqlen == data_size)
break;
else if (seqlen > data_size || seqlen > len)
return -1;
} else
free(pElem);
}
*svcReqSeq = pSeq;
scanned += seqlen;
*pDataType = dataType;
return scanned;
}
static int sdp_set_cstate_pdu(sdp_buf_t *buf, sdp_cont_state_t *cstate)
{
uint8_t *pdata = buf->data + buf->data_size;
int length = 0;
if (cstate) {
debug("Non null sdp_cstate_t id : 0x%lx", cstate->timestamp);
*(uint8_t *)pdata = sizeof(sdp_cont_state_t);
pdata += sizeof(uint8_t);
length += sizeof(uint8_t);
memcpy(pdata, cstate, sizeof(sdp_cont_state_t));
length += sizeof(sdp_cont_state_t);
} else {
// set "null" continuation state
*(uint8_t *)pdata = 0;
pdata += sizeof(uint8_t);
length += sizeof(uint8_t);
}
buf->data_size += length;
return length;
}
static sdp_cont_state_t *sdp_cstate_get(uint8_t *buffer)
{
uint8_t *pdata = buffer;
uint8_t cStateSize = *(uint8_t *)pdata;
/*
* Check if continuation state exists, if yes attempt
* to get response remainder from cache, else send error
*/
debug("Continuation State size : %d", cStateSize);
pdata += sizeof(uint8_t);
if (cStateSize != 0) {
sdp_cont_state_t *cstate = malloc(sizeof(sdp_cont_state_t));
if (!cstate)
return NULL;
memcpy(cstate, (sdp_cont_state_t *)pdata, sizeof(sdp_cont_state_t));
debug("Cstate TS : 0x%lx", cstate->timestamp);
debug("Bytes sent : %d", cstate->cStateValue.maxBytesSent);
return cstate;
}
return NULL;
}
/*
* The matching process is defined as "each and every UUID
* specified in the "search pattern" must be present in the
* "target pattern". Here "search pattern" is the set of UUIDs
* specified by the service discovery client and "target pattern"
* is the set of UUIDs present in a service record.
*
* Return 1 if each and every UUID in the search
* pattern exists in the target pattern, 0 if the
* match succeeds and -1 on error.
*/
static int sdp_match_uuid(sdp_list_t *search, sdp_list_t *pattern)
{
/*
* The target is a sorted list, so we need not look
* at all elements to confirm existence of an element
* from the search pattern
*/
int patlen = sdp_list_len(pattern);
if (patlen < sdp_list_len(search))
return -1;
for (; search; search = search->next) {
uuid_t *uuid128;
void *data = search->data;
sdp_list_t *list;
if (data == NULL)
return -1;
// create 128-bit form of the search UUID
uuid128 = sdp_uuid_to_uuid128((uuid_t *)data);
list = sdp_list_find(pattern, uuid128, sdp_uuid128_cmp);
bt_free(uuid128);
if (!list)
return 0;
}
return 1;
}
/*
* Service search request PDU. This method extracts the search pattern
* (a sequence of UUIDs) and calls the matching function
* to find matching services
*/
static int service_search_req(sdp_req_t *req, sdp_buf_t *buf)
{
int status = 0, i, plen, mlen, mtu, scanned;
sdp_list_t *pattern = NULL;
uint16_t expected, actual, rsp_count = 0;
uint8_t dtd;
sdp_cont_state_t *cstate = NULL;
uint8_t *pCacheBuffer = NULL;
int handleSize = 0;
uint32_t cStateId = 0;
short *pTotalRecordCount, *pCurrentRecordCount;
uint8_t *pdata = req->buf + sizeof(sdp_pdu_hdr_t);
scanned = extract_des(pdata, req->len - sizeof(sdp_pdu_hdr_t),
&pattern, &dtd, SDP_TYPE_UUID);
if (scanned == -1) {
status = SDP_INVALID_SYNTAX;
goto done;
}
pdata += scanned;
plen = ntohs(((sdp_pdu_hdr_t *)(req->buf))->plen);
mlen = scanned + sizeof(uint16_t) + 1;
// ensure we don't read past buffer
if (plen < mlen || plen != mlen + *(uint8_t *)(pdata+sizeof(uint16_t))) {
status = SDP_INVALID_SYNTAX;
goto done;
}
expected = ntohs(bt_get_unaligned((uint16_t *)pdata));
debug("Expected count: %d", expected);
debug("Bytes scanned : %d", scanned);
pdata += sizeof(uint16_t);
/*
* Check if continuation state exists, if yes attempt
* to get rsp remainder from cache, else send error
*/
cstate = sdp_cstate_get(pdata);
mtu = req->mtu - sizeof(sdp_pdu_hdr_t) - sizeof(uint16_t) - sizeof(uint16_t) - SDP_CONT_STATE_SIZE;
actual = MIN(expected, mtu >> 2);
/* make space in the rsp buffer for total and current record counts */
pdata = buf->data;
/* total service record count = 0 */
pTotalRecordCount = (short *)pdata;
bt_put_unaligned(0, (uint16_t *)pdata);
pdata += sizeof(uint16_t);
buf->data_size += sizeof(uint16_t);
/* current service record count = 0 */
pCurrentRecordCount = (short *)pdata;
bt_put_unaligned(0, (uint16_t *)pdata);
pdata += sizeof(uint16_t);
buf->data_size += sizeof(uint16_t);
if (cstate == NULL) {
/* for every record in the DB, do a pattern search */
sdp_list_t *list = sdp_get_record_list();
handleSize = 0;
for (; list && rsp_count < expected; list = list->next) {
sdp_record_t *rec = (sdp_record_t *) list->data;
debug("Checking svcRec : 0x%x", rec->handle);
if (sdp_match_uuid(pattern, rec->pattern) > 0 &&
sdp_check_access(rec->handle, &req->device)) {
rsp_count++;
bt_put_unaligned(htonl(rec->handle), (uint32_t *)pdata);
pdata += sizeof(uint32_t);
handleSize += sizeof(uint32_t);
}
}
debug("Match count: %d", rsp_count);
buf->data_size += handleSize;
bt_put_unaligned(htons(rsp_count), (uint16_t *)pTotalRecordCount);
bt_put_unaligned(htons(rsp_count), (uint16_t *)pCurrentRecordCount);
if (rsp_count > actual) {
/* cache the rsp and generate a continuation state */
cStateId = sdp_cstate_alloc_buf(buf);
/*
* subtract handleSize since we now send only
* a subset of handles
*/
buf->data_size -= handleSize;
} else {
/* NULL continuation state */
sdp_set_cstate_pdu(buf, NULL);
}
}
/* under both the conditions below, the rsp buffer is not built yet */
if (cstate || cStateId > 0) {
short lastIndex = 0;
if (cstate) {
/*
* Get the previous sdp_cont_state_t and obtain
* the cached rsp
*/
sdp_buf_t *pCache = sdp_get_cached_rsp(cstate);
if (pCache) {
pCacheBuffer = pCache->data;
/* get the rsp_count from the cached buffer */
rsp_count = ntohs(bt_get_unaligned((uint16_t *)pCacheBuffer));
/* get index of the last sdp_record_t sent */
lastIndex = cstate->cStateValue.lastIndexSent;
} else {
status = SDP_INVALID_CSTATE;
goto done;
}
} else {
pCacheBuffer = buf->data;
lastIndex = 0;
}
/*
* Set the local buffer pointer to after the
* current record count and increment the cached
* buffer pointer to beyond the counters
*/
pdata = (uint8_t *) pCurrentRecordCount + sizeof(uint16_t);
/* increment beyond the totalCount and the currentCount */
pCacheBuffer += 2 * sizeof(uint16_t);
if (cstate) {
handleSize = 0;
for (i = lastIndex; (i - lastIndex) < actual && i < rsp_count; i++) {
bt_put_unaligned(bt_get_unaligned((uint32_t *)(pCacheBuffer + i * sizeof(uint32_t))), (uint32_t *)pdata);
pdata += sizeof(uint32_t);
handleSize += sizeof(uint32_t);
}
} else {
handleSize = actual << 2;
i = actual;
}
buf->data_size += handleSize;
bt_put_unaligned(htons(rsp_count), (uint16_t *)pTotalRecordCount);
bt_put_unaligned(htons(i - lastIndex), (uint16_t *)pCurrentRecordCount);
if (i == rsp_count) {
/* set "null" continuationState */
sdp_set_cstate_pdu(buf, NULL);
} else {
/*
* there's more: set lastIndexSent to
* the new value and move on
*/
sdp_cont_state_t newState;
debug("Setting non-NULL sdp_cstate_t");
if (cstate)
memcpy((char *)&newState, cstate, sizeof(sdp_cont_state_t));
else {
memset((char *)&newState, 0, sizeof(sdp_cont_state_t));
newState.timestamp = cStateId;
}
newState.cStateValue.lastIndexSent = i;
sdp_set_cstate_pdu(buf, &newState);
}
}
done:
if (cstate)
free(cstate);
if (pattern)
sdp_list_free(pattern, free);
return status;
}
/*
* Extract attribute identifiers from the request PDU.
* Clients could request a subset of attributes (by id)
* from a service record, instead of the whole set. The
* requested identifiers are present in the PDU form of
* the request
*/
static int extract_attrs(sdp_record_t *rec, sdp_list_t *seq, uint8_t dtd, sdp_buf_t *buf)
{
if (!rec)
return SDP_INVALID_RECORD_HANDLE;
if (seq)
debug("Entries in attr seq : %d", sdp_list_len(seq));
else
debug("NULL attribute descriptor");
debug("AttrDataType : %d", dtd);
if (seq == NULL) {
debug("Attribute sequence is NULL");
return 0;
}
if (dtd == SDP_UINT16)
for (; seq; seq = seq->next) {
uint16_t attr = bt_get_unaligned((uint16_t *)seq->data);
sdp_data_t *a = (sdp_data_t *)sdp_data_get(rec, attr);
if (a)
sdp_append_to_pdu(buf, a);
}
else if (dtd == SDP_UINT32) {
sdp_buf_t pdu;
sdp_gen_record_pdu(rec, &pdu);
for (; seq; seq = seq->next) {
uint32_t range = bt_get_unaligned((uint32_t *)seq->data);
uint16_t attr;
uint16_t low = (0xffff0000 & range) >> 16;
uint16_t high = 0x0000ffff & range;
sdp_data_t *data;
debug("attr range : 0x%x", range);
debug("Low id : 0x%x", low);
debug("High id : 0x%x", high);
if (low == 0x0000 && high == 0xffff && pdu.data_size <= buf->buf_size) {
/* copy it */
memcpy(buf->data, pdu.data, pdu.data_size);
buf->data_size = pdu.data_size;
break;
}
/* (else) sub-range of attributes */
for (attr = low; attr < high; attr++) {
data = sdp_data_get(rec, attr);
if (data)
sdp_append_to_pdu(buf, data);
}
data = sdp_data_get(rec, high);
if (data)
sdp_append_to_pdu(buf, data);
}
free(pdu.data);
} else {
error("Unexpected data type : 0x%x", dtd);
error("Expect uint16_t or uint32_t");
return SDP_INVALID_SYNTAX;
}
return 0;
}
/*
* A request for the attributes of a service record.
* First check if the service record (specified by
* service record handle) exists, then call the attribute
* streaming function
*/
static int service_attr_req(sdp_req_t *req, sdp_buf_t *buf)
{
sdp_cont_state_t *cstate = NULL;
uint8_t *pResponse = NULL;
short cstate_size = 0;
sdp_list_t *seq = NULL;
uint8_t dtd = 0;
int scanned = 0;
int max_rsp_size;
int status = 0, plen, mlen;
uint8_t *pdata = req->buf + sizeof(sdp_pdu_hdr_t);
uint32_t handle = ntohl(bt_get_unaligned((uint32_t *)pdata));
pdata += sizeof(uint32_t);
max_rsp_size = ntohs(bt_get_unaligned((uint16_t *)pdata));
pdata += sizeof(uint16_t);
/* extract the attribute list */
scanned = extract_des(pdata, req->len - sizeof(sdp_pdu_hdr_t),
&seq, &dtd, SDP_TYPE_ANY);
if (scanned == -1) {
status = SDP_INVALID_SYNTAX;
goto done;
}
pdata += scanned;
plen = ntohs(((sdp_pdu_hdr_t *)(req->buf))->plen);
mlen = scanned + sizeof(uint32_t) + sizeof(uint16_t) + 1;
// ensure we don't read past buffer
if (plen < mlen || plen != mlen + *(uint8_t *)pdata) {
status = SDP_INVALID_SYNTAX;
goto done;
}
/*
* if continuation state exists, attempt
* to get rsp remainder from cache, else send error
*/
cstate = sdp_cstate_get(pdata);
debug("SvcRecHandle : 0x%x", handle);
debug("max_rsp_size : %d", max_rsp_size);
/*
* Calculate Attribute size acording to MTU
* We can send only (MTU - sizeof(sdp_pdu_hdr_t) - sizeof(sdp_cont_state_t))
*/
max_rsp_size = MIN(max_rsp_size, req->mtu - sizeof(sdp_pdu_hdr_t) -
sizeof(uint32_t) - SDP_CONT_STATE_SIZE - sizeof(uint16_t));
/* pull header for AttributeList byte count */
buf->data += sizeof(uint16_t);
buf->buf_size -= sizeof(uint16_t);
if (cstate) {
sdp_buf_t *pCache = sdp_get_cached_rsp(cstate);
debug("Obtained cached rsp : %p", pCache);
if (pCache) {
short sent = MIN(max_rsp_size, pCache->data_size - cstate->cStateValue.maxBytesSent);
pResponse = pCache->data;
memcpy(buf->data, pResponse + cstate->cStateValue.maxBytesSent, sent);
buf->data_size += sent;
cstate->cStateValue.maxBytesSent += sent;
debug("Response size : %d sending now : %d bytes sent so far : %d",
pCache->data_size, sent, cstate->cStateValue.maxBytesSent);
if (cstate->cStateValue.maxBytesSent == pCache->data_size)
cstate_size = sdp_set_cstate_pdu(buf, NULL);
else
cstate_size = sdp_set_cstate_pdu(buf, cstate);
} else {
status = SDP_INVALID_CSTATE;
error("NULL cache buffer and non-NULL continuation state");
}
} else {
sdp_record_t *rec = sdp_record_find(handle);
status = extract_attrs(rec, seq, dtd, buf);
if (buf->data_size > max_rsp_size) {
sdp_cont_state_t newState;
memset((char *)&newState, 0, sizeof(sdp_cont_state_t));
newState.timestamp = sdp_cstate_alloc_buf(buf);
/*
* Reset the buffer size to the maximum expected and
* set the sdp_cont_state_t
*/
debug("Creating continuation state of size : %d", buf->data_size);
buf->data_size = max_rsp_size;
newState.cStateValue.maxBytesSent = max_rsp_size;
cstate_size = sdp_set_cstate_pdu(buf, &newState);
} else {
if (buf->data_size == 0)
sdp_append_to_buf(buf, 0, 0);
cstate_size = sdp_set_cstate_pdu(buf, NULL);
}
}
// push header
buf->data -= sizeof(uint16_t);
buf->buf_size += sizeof(uint16_t);
done:
if (cstate)
free(cstate);
if (seq)
sdp_list_free(seq, free);
if (status)
return status;
/* set attribute list byte count */
bt_put_unaligned(htons(buf->data_size - cstate_size), (uint16_t *)buf->data);
buf->data_size += sizeof(uint16_t);
return 0;
}
/*
* combined service search and attribute extraction
*/
static int service_search_attr_req(sdp_req_t *req, sdp_buf_t *buf)
{
int status = 0, plen, totscanned;
uint8_t *pdata, *pResponse = NULL;
int scanned, max, rsp_count = 0;
sdp_list_t *pattern = NULL, *seq = NULL, *svcList;
sdp_cont_state_t *cstate = NULL;
short cstate_size = 0;
uint8_t dtd = 0;
sdp_buf_t tmpbuf;
tmpbuf.data = NULL;
pdata = req->buf + sizeof(sdp_pdu_hdr_t);
scanned = extract_des(pdata, req->len - sizeof(sdp_pdu_hdr_t),
&pattern, &dtd, SDP_TYPE_UUID);
if (scanned == -1) {
status = SDP_INVALID_SYNTAX;
goto done;
}
totscanned = scanned;
debug("Bytes scanned: %d", scanned);
pdata += scanned;
max = ntohs(bt_get_unaligned((uint16_t *)pdata));
pdata += sizeof(uint16_t);
debug("Max Attr expected: %d", max);
/* extract the attribute list */
scanned = extract_des(pdata, req->len - sizeof(sdp_pdu_hdr_t),
&seq, &dtd, SDP_TYPE_ANY);
if (scanned == -1) {
status = SDP_INVALID_SYNTAX;
goto done;
}
pdata += scanned;
totscanned += scanned + sizeof(uint16_t) + 1;
plen = ntohs(((sdp_pdu_hdr_t *)(req->buf))->plen);
if (plen < totscanned || plen != totscanned + *(uint8_t *)pdata) {
status = SDP_INVALID_SYNTAX;
goto done;
}
/*
* if continuation state exists attempt
* to get rsp remainder from cache, else send error
*/
cstate = sdp_cstate_get(pdata); // continuation information
svcList = sdp_get_record_list();
tmpbuf.data = malloc(USHRT_MAX);
tmpbuf.data_size = 0;
tmpbuf.buf_size = USHRT_MAX;
memset(tmpbuf.data, 0, USHRT_MAX);
/*
* Calculate Attribute size acording to MTU
* We can send only (MTU - sizeof(sdp_pdu_hdr_t) - sizeof(sdp_cont_state_t))
*/
max = MIN(max, req->mtu - sizeof(sdp_pdu_hdr_t) - SDP_CONT_STATE_SIZE - sizeof(uint16_t));
/* pull header for AttributeList byte count */
buf->data += sizeof(uint16_t);
buf->buf_size -= sizeof(uint16_t);
if (cstate == NULL) {
/* no continuation state -> create new response */
sdp_list_t *p;
for (p = svcList; p; p = p->next) {
sdp_record_t *rec = (sdp_record_t *) p->data;
if (sdp_match_uuid(pattern, rec->pattern) > 0 &&
sdp_check_access(rec->handle, &req->device)) {
rsp_count++;
status = extract_attrs(rec, seq, dtd, &tmpbuf);
debug("Response count : %d", rsp_count);
debug("Local PDU size : %d", tmpbuf.data_size);
if (status) {
debug("Extract attr from record returns err");
break;
}
if (buf->data_size + tmpbuf.data_size < buf->buf_size) {
// to be sure no relocations
sdp_append_to_buf(buf, tmpbuf.data, tmpbuf.data_size);
tmpbuf.data_size = 0;
memset(tmpbuf.data, 0, USHRT_MAX);
} else {
error("Relocation needed");
break;
}
debug("Net PDU size : %d", buf->data_size);
}
}
if (buf->data_size > max) {
sdp_cont_state_t newState;
memset((char *)&newState, 0, sizeof(sdp_cont_state_t));
newState.timestamp = sdp_cstate_alloc_buf(buf);
/*
* Reset the buffer size to the maximum expected and
* set the sdp_cont_state_t
*/
buf->data_size = max;
newState.cStateValue.maxBytesSent = max;
cstate_size = sdp_set_cstate_pdu(buf, &newState);
} else
cstate_size = sdp_set_cstate_pdu(buf, NULL);
} else {
/* continuation State exists -> get from cache */
sdp_buf_t *pCache = sdp_get_cached_rsp(cstate);
if (pCache) {
uint16_t sent = MIN(max, pCache->data_size - cstate->cStateValue.maxBytesSent);
pResponse = pCache->data;
memcpy(buf->data, pResponse + cstate->cStateValue.maxBytesSent, sent);
buf->data_size += sent;
cstate->cStateValue.maxBytesSent += sent;
if (cstate->cStateValue.maxBytesSent == pCache->data_size)
cstate_size = sdp_set_cstate_pdu(buf, NULL);
else
cstate_size = sdp_set_cstate_pdu(buf, cstate);
} else {
status = SDP_INVALID_CSTATE;
debug("Non-null continuation state, but null cache buffer");
}
}
if (!rsp_count && !cstate) {
// found nothing
buf->data_size = 0;
sdp_append_to_buf(buf, tmpbuf.data, tmpbuf.data_size);
sdp_set_cstate_pdu(buf, NULL);
}
// push header
buf->data -= sizeof(uint16_t);
buf->buf_size += sizeof(uint16_t);
if (!status) {
/* set attribute list byte count */
bt_put_unaligned(htons(buf->data_size - cstate_size), (uint16_t *)buf->data);
buf->data_size += sizeof(uint16_t);
}
done:
if (cstate)
free(cstate);
if (tmpbuf.data)
free(tmpbuf.data);
if (pattern)
sdp_list_free(pattern, free);
if (seq)
sdp_list_free(seq, free);
return status;
}
/*
* Top level request processor. Calls the appropriate processing
* function based on request type. Handles service registration
* client requests also.
*/
static void process_request(sdp_req_t *req)
{
sdp_pdu_hdr_t *reqhdr = (sdp_pdu_hdr_t *)req->buf;
sdp_pdu_hdr_t *rsphdr;
sdp_buf_t rsp;
uint8_t *buf = malloc(USHRT_MAX);
int sent = 0;
int status = SDP_INVALID_SYNTAX;
memset(buf, 0, USHRT_MAX);
rsp.data = buf + sizeof(sdp_pdu_hdr_t);
rsp.data_size = 0;
rsp.buf_size = USHRT_MAX - sizeof(sdp_pdu_hdr_t);
rsphdr = (sdp_pdu_hdr_t *)buf;
if (ntohs(reqhdr->plen) != req->len - sizeof(sdp_pdu_hdr_t)) {
status = SDP_INVALID_PDU_SIZE;
goto send_rsp;
}
switch (reqhdr->pdu_id) {
case SDP_SVC_SEARCH_REQ:
debug("Got a svc srch req");
status = service_search_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_SEARCH_RSP;
break;
case SDP_SVC_ATTR_REQ:
debug("Got a svc attr req");
status = service_attr_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_ATTR_RSP;
break;
case SDP_SVC_SEARCH_ATTR_REQ:
debug("Got a svc srch attr req");
status = service_search_attr_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_SEARCH_ATTR_RSP;
break;
/* Following requests are allowed only for local connections */
case SDP_SVC_REGISTER_REQ:
debug("Service register request");
if (req->local) {
status = service_register_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_REGISTER_RSP;
}
break;
case SDP_SVC_UPDATE_REQ:
debug("Service update request");
if (req->local) {
status = service_update_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_UPDATE_RSP;
}
break;
case SDP_SVC_REMOVE_REQ:
debug("Service removal request");
if (req->local) {
status = service_remove_req(req, &rsp);
rsphdr->pdu_id = SDP_SVC_REMOVE_RSP;
}
break;
default:
error("Unknown PDU ID : 0x%x received", reqhdr->pdu_id);
status = SDP_INVALID_SYNTAX;
break;
}
send_rsp:
if (status) {
rsphdr->pdu_id = SDP_ERROR_RSP;
bt_put_unaligned(htons(status), (uint16_t *)rsp.data);
rsp.data_size = sizeof(uint16_t);
}
debug("Sending rsp. status %d", status);
rsphdr->tid = reqhdr->tid;
rsphdr->plen = htons(rsp.data_size);
/* point back to the real buffer start and set the real rsp length */
rsp.data_size += sizeof(sdp_pdu_hdr_t);
rsp.data = buf;
/* stream the rsp PDU */
sent = send(req->sock, rsp.data, rsp.data_size, 0);
debug("Bytes Sent : %d", sent);
free(rsp.data);
free(req->buf);
}
void handle_request(int sk, uint8_t *data, int len)
{
struct sockaddr_l2 sa;
socklen_t size;
sdp_req_t req;
size = sizeof(sa);
if (getpeername(sk, (struct sockaddr *) &sa, &size) < 0)
return;
if (sa.l2_family == AF_BLUETOOTH) {
struct l2cap_options lo;
memset(&lo, 0, sizeof(lo));
size = sizeof(lo);
getsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &lo, &size);
bacpy(&req.bdaddr, &sa.l2_bdaddr);
req.mtu = lo.omtu;
req.local = 0;
memset(&sa, 0, sizeof(sa));
size = sizeof(sa);
getsockname(sk, (struct sockaddr *) &sa, &size);
bacpy(&req.device, &sa.l2_bdaddr);
} else {
bacpy(&req.device, BDADDR_ANY);
bacpy(&req.bdaddr, BDADDR_LOCAL);
req.mtu = 2048;
req.local = 1;
}
req.sock = sk;
req.buf = data;
req.len = len;
process_request(&req);
}
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