267 lines
7.3 KiB
C
267 lines
7.3 KiB
C
/*
|
|
* rfcomm_sdp.c
|
|
*
|
|
* Copyright (c) 2003 Maksim Yevmenkin <m_evmenkin@yahoo.com>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* $Id: rfcomm_sdp.c,v 1.1 2003/09/07 18:15:55 max Exp $
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <bluetooth.h>
|
|
#include <errno.h>
|
|
#include <sdp.h>
|
|
#include <stdio.h>
|
|
|
|
#undef PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE
|
|
#define PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE 256
|
|
|
|
#undef PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE
|
|
#define PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE 12
|
|
|
|
static int rfcomm_proto_list_parse (uint8_t const *start, uint8_t const *end,
|
|
int *channel, int *error);
|
|
|
|
/*
|
|
* Lookup RFCOMM channel number in the Protocol Descriptor List
|
|
*/
|
|
|
|
#undef rfcomm_channel_lookup_exit
|
|
#define rfcomm_channel_lookup_exit(e) { \
|
|
if (error != NULL) \
|
|
*error = (e); \
|
|
if (ss != NULL) { \
|
|
sdp_close(ss); \
|
|
ss = NULL; \
|
|
} \
|
|
return (((e) == 0)? 0 : -1); \
|
|
}
|
|
|
|
int
|
|
rfcomm_channel_lookup(bdaddr_t const *local, bdaddr_t const *remote,
|
|
int service, int *channel, int *error)
|
|
{
|
|
uint8_t buffer[PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE];
|
|
void *ss = NULL;
|
|
uint16_t serv = (uint16_t) service;
|
|
uint32_t attr = SDP_ATTR_RANGE(
|
|
SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST,
|
|
SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST);
|
|
sdp_attr_t proto = { SDP_ATTR_INVALID,0,sizeof(buffer),buffer };
|
|
uint32_t type, len;
|
|
|
|
if (local == NULL)
|
|
local = NG_HCI_BDADDR_ANY;
|
|
if (remote == NULL || channel == NULL)
|
|
rfcomm_channel_lookup_exit(EINVAL);
|
|
|
|
if ((ss = sdp_open(local, remote)) == NULL)
|
|
rfcomm_channel_lookup_exit(ENOMEM);
|
|
if (sdp_error(ss) != 0)
|
|
rfcomm_channel_lookup_exit(sdp_error(ss));
|
|
|
|
if (sdp_search(ss, 1, &serv, 1, &attr, 1, &proto) != 0)
|
|
rfcomm_channel_lookup_exit(sdp_error(ss));
|
|
if (proto.flags != SDP_ATTR_OK)
|
|
rfcomm_channel_lookup_exit(ENOATTR);
|
|
|
|
sdp_close(ss);
|
|
ss = NULL;
|
|
|
|
/*
|
|
* If it is possible for more than one kind of protocol stack to be
|
|
* used to gain access to the service, the ProtocolDescriptorList
|
|
* takes the form of a data element alternative. We always use the
|
|
* first protocol stack.
|
|
*
|
|
* A minimal Protocol Descriptor List for RFCOMM based service would
|
|
* look like
|
|
*
|
|
* seq8 len8 - 2 bytes
|
|
* seq8 len8 - 2 bytes
|
|
* uuid16 value16 - 3 bytes L2CAP
|
|
* seq8 len8 - 2 bytes
|
|
* uuid16 value16 - 3 bytes RFCOMM
|
|
* uint8 value8 - 2 bytes RFCOMM param #1
|
|
* =========
|
|
* 14 bytes
|
|
*
|
|
* Lets not count first [seq8 len8] wrapper, so the minimal size of
|
|
* the Protocol Descriptor List (the data we are actually interested
|
|
* in) for RFCOMM based service would be 12 bytes.
|
|
*/
|
|
|
|
if (proto.vlen < PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE)
|
|
rfcomm_channel_lookup_exit(EINVAL);
|
|
|
|
SDP_GET8(type, proto.value);
|
|
|
|
if (type == SDP_DATA_ALT8) {
|
|
SDP_GET8(len, proto.value);
|
|
} else if (type == SDP_DATA_ALT16) {
|
|
SDP_GET16(len, proto.value);
|
|
} else if (type == SDP_DATA_ALT32) {
|
|
SDP_GET32(len, proto.value);
|
|
} else
|
|
len = 0;
|
|
|
|
if (len > 0)
|
|
SDP_GET8(type, proto.value);
|
|
|
|
switch (type) {
|
|
case SDP_DATA_SEQ8:
|
|
SDP_GET8(len, proto.value);
|
|
break;
|
|
|
|
case SDP_DATA_SEQ16:
|
|
SDP_GET16(len, proto.value);
|
|
break;
|
|
|
|
case SDP_DATA_SEQ32:
|
|
SDP_GET32(len, proto.value);
|
|
break;
|
|
|
|
default:
|
|
rfcomm_channel_lookup_exit(ENOATTR);
|
|
/* NOT REACHED */
|
|
}
|
|
|
|
if (len < PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE)
|
|
rfcomm_channel_lookup_exit(EINVAL);
|
|
|
|
return (rfcomm_proto_list_parse(proto.value,
|
|
buffer + proto.vlen, channel, error));
|
|
}
|
|
|
|
/*
|
|
* Parse protocol descriptor list
|
|
*
|
|
* The ProtocolDescriptorList attribute describes one or more protocol
|
|
* stacks that may be used to gain access to the service described by
|
|
* the service record. If the ProtocolDescriptorList describes a single
|
|
* stack, it takes the form of a data element sequence in which each
|
|
* element of the sequence is a protocol descriptor.
|
|
*/
|
|
|
|
#undef rfcomm_proto_list_parse_exit
|
|
#define rfcomm_proto_list_parse_exit(e) { \
|
|
if (error != NULL) \
|
|
*error = (e); \
|
|
return (((e) == 0)? 0 : -1); \
|
|
}
|
|
|
|
static int
|
|
rfcomm_proto_list_parse(uint8_t const *start, uint8_t const *end,
|
|
int *channel, int *error)
|
|
{
|
|
int type, len, value;
|
|
|
|
while (start < end) {
|
|
|
|
/*
|
|
* Parse protocol descriptor
|
|
*
|
|
* A protocol descriptor identifies a communications protocol
|
|
* and provides protocol specific parameters. A protocol
|
|
* descriptor is represented as a data element sequence. The
|
|
* first data element in the sequence must be the UUID that
|
|
* identifies the protocol. Additional data elements optionally
|
|
* provide protocol specific information, such as the L2CAP
|
|
* protocol/service multiplexer (PSM) and the RFCOMM server
|
|
* channel number (CN).
|
|
*/
|
|
|
|
/* We must have at least one byte (type) */
|
|
if (end - start < 1)
|
|
rfcomm_proto_list_parse_exit(EINVAL)
|
|
|
|
SDP_GET8(type, start);
|
|
switch (type) {
|
|
case SDP_DATA_SEQ8:
|
|
SDP_GET8(len, start);
|
|
break;
|
|
|
|
case SDP_DATA_SEQ16:
|
|
SDP_GET16(len, start);
|
|
break;
|
|
|
|
case SDP_DATA_SEQ32:
|
|
SDP_GET32(len, start);
|
|
break;
|
|
|
|
default:
|
|
rfcomm_proto_list_parse_exit(ENOATTR)
|
|
/* NOT REACHED */
|
|
}
|
|
|
|
/* We must have at least 3 bytes (type + UUID16) */
|
|
if (end - start < 3)
|
|
rfcomm_proto_list_parse_exit(EINVAL);
|
|
|
|
/* Get protocol UUID */
|
|
SDP_GET8(type, start); len -= sizeof(uint8_t);
|
|
switch (type) {
|
|
case SDP_DATA_UUID16:
|
|
SDP_GET16(value, start); len -= sizeof(uint16_t);
|
|
if (value != SDP_UUID_PROTOCOL_RFCOMM)
|
|
goto next_protocol;
|
|
break;
|
|
|
|
case SDP_DATA_UUID32: /* XXX FIXME can we have 32-bit UUID */
|
|
case SDP_DATA_UUID128: /* XXX FIXME can we have 128-bit UUID */
|
|
default:
|
|
rfcomm_proto_list_parse_exit(ENOATTR);
|
|
/* NOT REACHED */
|
|
}
|
|
|
|
/*
|
|
* First protocol specific parameter for RFCOMM procotol must
|
|
* be uint8 that represents RFCOMM channel number. So we must
|
|
* have at least two bytes.
|
|
*/
|
|
|
|
if (end - start < 2)
|
|
rfcomm_proto_list_parse_exit(EINVAL);
|
|
|
|
SDP_GET8(type, start);
|
|
if (type != SDP_DATA_UINT8)
|
|
rfcomm_proto_list_parse_exit(ENOATTR);
|
|
|
|
SDP_GET8(*channel, start);
|
|
|
|
rfcomm_proto_list_parse_exit(0);
|
|
/* NOT REACHED */
|
|
next_protocol:
|
|
start += len;
|
|
}
|
|
|
|
/*
|
|
* If we got here then it means we could not find RFCOMM protocol
|
|
* descriptor, but the reply format was actually valid.
|
|
*/
|
|
|
|
rfcomm_proto_list_parse_exit(ENOATTR);
|
|
}
|
|
|