1121054Semax/* 2121054Semax * rfcomm_sdp.c 3121054Semax * 4121054Semax * Copyright (c) 2003 Maksim Yevmenkin <m_evmenkin@yahoo.com> 5121054Semax * All rights reserved. 6121054Semax * 7121054Semax * Redistribution and use in source and binary forms, with or without 8121054Semax * modification, are permitted provided that the following conditions 9121054Semax * are met: 10121054Semax * 1. Redistributions of source code must retain the above copyright 11121054Semax * notice, this list of conditions and the following disclaimer. 12121054Semax * 2. Redistributions in binary form must reproduce the above copyright 13121054Semax * notice, this list of conditions and the following disclaimer in the 14121054Semax * documentation and/or other materials provided with the distribution. 15121054Semax * 16121054Semax * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17121054Semax * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18121054Semax * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19121054Semax * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20121054Semax * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21121054Semax * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22121054Semax * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23121054Semax * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24121054Semax * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25121054Semax * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26121054Semax * SUCH DAMAGE. 27121054Semax * 28121054Semax * $Id: rfcomm_sdp.c,v 1.1 2003/09/07 18:15:55 max Exp $ 29121054Semax * $FreeBSD$ 30121054Semax */ 31121054Semax 32121054Semax#include <bluetooth.h> 33121054Semax#include <errno.h> 34121054Semax#include <sdp.h> 35121054Semax#include <stdio.h> 36121054Semax 37121054Semax#undef PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE 38121054Semax#define PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE 256 39121054Semax 40121054Semax#undef PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE 41121054Semax#define PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE 12 42121054Semax 43128077Semaxstatic int rfcomm_proto_list_parse (uint8_t const *start, uint8_t const *end, 44121054Semax int *channel, int *error); 45121054Semax 46121054Semax/* 47121054Semax * Lookup RFCOMM channel number in the Protocol Descriptor List 48121054Semax */ 49121054Semax 50121054Semax#undef rfcomm_channel_lookup_exit 51121054Semax#define rfcomm_channel_lookup_exit(e) { \ 52121054Semax if (error != NULL) \ 53121054Semax *error = (e); \ 54121054Semax if (ss != NULL) { \ 55121054Semax sdp_close(ss); \ 56121054Semax ss = NULL; \ 57121054Semax } \ 58121054Semax return (((e) == 0)? 0 : -1); \ 59121054Semax} 60121054Semax 61121054Semaxint 62121054Semaxrfcomm_channel_lookup(bdaddr_t const *local, bdaddr_t const *remote, 63121054Semax int service, int *channel, int *error) 64121054Semax{ 65128077Semax uint8_t buffer[PROTOCOL_DESCRIPTOR_LIST_BUFFER_SIZE]; 66128077Semax void *ss = NULL; 67128077Semax uint16_t serv = (uint16_t) service; 68128077Semax uint32_t attr = SDP_ATTR_RANGE( 69121054Semax SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST, 70121054Semax SDP_ATTR_PROTOCOL_DESCRIPTOR_LIST); 71128077Semax sdp_attr_t proto = { SDP_ATTR_INVALID,0,sizeof(buffer),buffer }; 72128077Semax uint32_t type, len; 73121054Semax 74121054Semax if (local == NULL) 75121054Semax local = NG_HCI_BDADDR_ANY; 76121054Semax if (remote == NULL || channel == NULL) 77121054Semax rfcomm_channel_lookup_exit(EINVAL); 78121054Semax 79121054Semax if ((ss = sdp_open(local, remote)) == NULL) 80121054Semax rfcomm_channel_lookup_exit(ENOMEM); 81121054Semax if (sdp_error(ss) != 0) 82121054Semax rfcomm_channel_lookup_exit(sdp_error(ss)); 83121054Semax 84121054Semax if (sdp_search(ss, 1, &serv, 1, &attr, 1, &proto) != 0) 85121054Semax rfcomm_channel_lookup_exit(sdp_error(ss)); 86121054Semax if (proto.flags != SDP_ATTR_OK) 87121054Semax rfcomm_channel_lookup_exit(ENOATTR); 88121054Semax 89121054Semax sdp_close(ss); 90121054Semax ss = NULL; 91121054Semax 92121054Semax /* 93121054Semax * If it is possible for more than one kind of protocol stack to be 94121054Semax * used to gain access to the service, the ProtocolDescriptorList 95121054Semax * takes the form of a data element alternative. We always use the 96121054Semax * first protocol stack. 97121054Semax * 98121054Semax * A minimal Protocol Descriptor List for RFCOMM based service would 99121054Semax * look like 100121054Semax * 101121054Semax * seq8 len8 - 2 bytes 102121054Semax * seq8 len8 - 2 bytes 103121054Semax * uuid16 value16 - 3 bytes L2CAP 104121054Semax * seq8 len8 - 2 bytes 105121054Semax * uuid16 value16 - 3 bytes RFCOMM 106121054Semax * uint8 value8 - 2 bytes RFCOMM param #1 107121054Semax * ========= 108121054Semax * 14 bytes 109121054Semax * 110121054Semax * Lets not count first [seq8 len8] wrapper, so the minimal size of 111121054Semax * the Protocol Descriptor List (the data we are actually interested 112121054Semax * in) for RFCOMM based service would be 12 bytes. 113121054Semax */ 114121054Semax 115121054Semax if (proto.vlen < PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE) 116121054Semax rfcomm_channel_lookup_exit(EINVAL); 117121054Semax 118121054Semax SDP_GET8(type, proto.value); 119121054Semax 120121054Semax if (type == SDP_DATA_ALT8) { 121121054Semax SDP_GET8(len, proto.value); 122121054Semax } else if (type == SDP_DATA_ALT16) { 123121054Semax SDP_GET16(len, proto.value); 124121054Semax } else if (type == SDP_DATA_ALT32) { 125121054Semax SDP_GET32(len, proto.value); 126121054Semax } else 127121054Semax len = 0; 128121054Semax 129121054Semax if (len > 0) 130121054Semax SDP_GET8(type, proto.value); 131121054Semax 132121054Semax switch (type) { 133121054Semax case SDP_DATA_SEQ8: 134121054Semax SDP_GET8(len, proto.value); 135121054Semax break; 136121054Semax 137121054Semax case SDP_DATA_SEQ16: 138121054Semax SDP_GET16(len, proto.value); 139121054Semax break; 140121054Semax 141121054Semax case SDP_DATA_SEQ32: 142121054Semax SDP_GET32(len, proto.value); 143121054Semax break; 144121054Semax 145121054Semax default: 146121054Semax rfcomm_channel_lookup_exit(ENOATTR); 147121054Semax /* NOT REACHED */ 148121054Semax } 149121054Semax 150121054Semax if (len < PROTOCOL_DESCRIPTOR_LIST_MINIMAL_SIZE) 151121054Semax rfcomm_channel_lookup_exit(EINVAL); 152121054Semax 153121054Semax return (rfcomm_proto_list_parse(proto.value, 154121054Semax buffer + proto.vlen, channel, error)); 155121054Semax} 156121054Semax 157121054Semax/* 158121054Semax * Parse protocol descriptor list 159121054Semax * 160121054Semax * The ProtocolDescriptorList attribute describes one or more protocol 161121054Semax * stacks that may be used to gain access to the service described by 162121054Semax * the service record. If the ProtocolDescriptorList describes a single 163121054Semax * stack, it takes the form of a data element sequence in which each 164121054Semax * element of the sequence is a protocol descriptor. 165121054Semax */ 166121054Semax 167121054Semax#undef rfcomm_proto_list_parse_exit 168121054Semax#define rfcomm_proto_list_parse_exit(e) { \ 169121054Semax if (error != NULL) \ 170121054Semax *error = (e); \ 171121054Semax return (((e) == 0)? 0 : -1); \ 172121054Semax} 173121054Semax 174121054Semaxstatic int 175128077Semaxrfcomm_proto_list_parse(uint8_t const *start, uint8_t const *end, 176121054Semax int *channel, int *error) 177121054Semax{ 178121054Semax int type, len, value; 179121054Semax 180121054Semax while (start < end) { 181121054Semax 182121054Semax /* 183121054Semax * Parse protocol descriptor 184121054Semax * 185121054Semax * A protocol descriptor identifies a communications protocol 186121054Semax * and provides protocol specific parameters. A protocol 187121054Semax * descriptor is represented as a data element sequence. The 188121054Semax * first data element in the sequence must be the UUID that 189121054Semax * identifies the protocol. Additional data elements optionally 190121054Semax * provide protocol specific information, such as the L2CAP 191121054Semax * protocol/service multiplexer (PSM) and the RFCOMM server 192121054Semax * channel number (CN). 193121054Semax */ 194121054Semax 195121054Semax /* We must have at least one byte (type) */ 196121054Semax if (end - start < 1) 197121054Semax rfcomm_proto_list_parse_exit(EINVAL) 198121054Semax 199121054Semax SDP_GET8(type, start); 200121054Semax switch (type) { 201121054Semax case SDP_DATA_SEQ8: 202121054Semax SDP_GET8(len, start); 203121054Semax break; 204121054Semax 205121054Semax case SDP_DATA_SEQ16: 206121054Semax SDP_GET16(len, start); 207121054Semax break; 208121054Semax 209121054Semax case SDP_DATA_SEQ32: 210121054Semax SDP_GET32(len, start); 211121054Semax break; 212121054Semax 213121054Semax default: 214121054Semax rfcomm_proto_list_parse_exit(ENOATTR) 215121054Semax /* NOT REACHED */ 216121054Semax } 217121054Semax 218121054Semax /* We must have at least 3 bytes (type + UUID16) */ 219121054Semax if (end - start < 3) 220121054Semax rfcomm_proto_list_parse_exit(EINVAL); 221121054Semax 222121054Semax /* Get protocol UUID */ 223128077Semax SDP_GET8(type, start); len -= sizeof(uint8_t); 224121054Semax switch (type) { 225121054Semax case SDP_DATA_UUID16: 226128077Semax SDP_GET16(value, start); len -= sizeof(uint16_t); 227121054Semax if (value != SDP_UUID_PROTOCOL_RFCOMM) 228121054Semax goto next_protocol; 229121054Semax break; 230121054Semax 231121054Semax case SDP_DATA_UUID32: /* XXX FIXME can we have 32-bit UUID */ 232121054Semax case SDP_DATA_UUID128: /* XXX FIXME can we have 128-bit UUID */ 233121054Semax default: 234121054Semax rfcomm_proto_list_parse_exit(ENOATTR); 235121054Semax /* NOT REACHED */ 236121054Semax } 237121054Semax 238121054Semax /* 239121054Semax * First protocol specific parameter for RFCOMM procotol must 240121054Semax * be uint8 that represents RFCOMM channel number. So we must 241121054Semax * have at least two bytes. 242121054Semax */ 243121054Semax 244121054Semax if (end - start < 2) 245121054Semax rfcomm_proto_list_parse_exit(EINVAL); 246121054Semax 247121054Semax SDP_GET8(type, start); 248121054Semax if (type != SDP_DATA_UINT8) 249121054Semax rfcomm_proto_list_parse_exit(ENOATTR); 250121054Semax 251121054Semax SDP_GET8(*channel, start); 252121054Semax 253121054Semax rfcomm_proto_list_parse_exit(0); 254121054Semax /* NOT REACHED */ 255121054Semaxnext_protocol: 256121054Semax start += len; 257121054Semax } 258121054Semax 259121054Semax /* 260121054Semax * If we got here then it means we could not find RFCOMM protocol 261121054Semax * descriptor, but the reply format was actually valid. 262121054Semax */ 263121054Semax 264121054Semax rfcomm_proto_list_parse_exit(ENOATTR); 265121054Semax} 266121054Semax 267