path: root/sdpd/main.c

/*
   Service Discovery Protocol (SDP)
   Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>, Stephen Crane <steve.crane@rococosoft.com>
   
   Based on original SDP implementation by Nokia Corporation.
   Copyright (C) 2001,2002 Nokia Corporation.
   Original author Guruprasad Krishnamurthy <guruprasad.krishnamurthy@nokia.com>
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 as
   published by the Free Software Foundation;
   
   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY CLAIM,
   OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER
   RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
   USE OR PERFORMANCE OF THIS SOFTWARE.
   
   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, COPYRIGHTS,
   TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS SOFTWARE IS DISCLAIMED.
*/

/*
   SDP server initialization and connection handling

   Fixes:
	Guruprasad Krishnamurthy <guruprasad.krishnamurthy@nokia.com>
	Imre Deak <ext-imre.deak@nokia.com>
*/

/*
 * $Id$
 */
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <getopt.h>
#include <sys/un.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/socket.h>

#include <bluetooth/bluetooth.h>
#include <bluetooth/l2cap.h>
#include <bluetooth/sdp.h>
#include <bluetooth/sdp_lib.h>
#include <bluetooth/sdp_internal.h>

#include "sdpd.h"

static int l2cap_sock, unix_sock;
static fd_set active_fdset;
static int active_maxfd;

sdp_record_t *server;

/*
 * List of version numbers supported by the SDP server.
 * Add to this list when newer versions are supported.
 */
static sdp_version_t sdpVnumArray[1] = {
	{1, 0}
};
const int sdpServerVnumEntries = 1;

/*
 * The service database state is an attribute of the service record
 * of the SDP server itself. This attribute is guaranteed to
 * change if any of the contents of the service repository
 * changes. This function updates the timestamp of value of
 * the svcDBState attribute
 * Set the SDP server DB. Simply a timestamp which is the marker
 * when the DB was modified.
 */
void update_db_timestamp(void)
{
	uint32_t dbts = sdp_get_time();
	sdp_data_t *d = sdp_data_alloc(SDP_UINT32, &dbts);
	sdp_attr_replace(server, SDP_ATTR_SVCDB_STATE, d);
}

static void add_lang_attr(sdp_record_t *r)
{
	sdp_lang_attr_t base_lang;
	sdp_list_t *langs = 0;

	base_lang.code_ISO639 = (0x65 << 8) | 0x6e;
	// UTF-8 MIBenum (http://www.iana.org/assignments/character-sets)
	base_lang.encoding = 106;
	base_lang.base_offset = SDP_PRIMARY_LANG_BASE;
	langs = sdp_list_append(0, &base_lang);
	sdp_set_lang_attr(r, langs);
	sdp_list_free(langs, 0);
}

static void register_public_browse_group(void)
{
	sdp_list_t *browselist;
	uuid_t bgscid, pbgid;
	sdp_data_t *sdpdata;
	sdp_record_t *browse = sdp_record_alloc();

	browse->handle = (uint32_t)browse;
	sdp_record_add(browse);
	sdpdata = sdp_data_alloc(SDP_UINT32, &browse->handle);
	sdp_attr_add(browse, SDP_ATTR_RECORD_HANDLE, sdpdata);

	add_lang_attr(browse);
	sdp_set_info_attr(browse, "Public Browse Group Root", "BlueZ", "Root of public browse hierarchy");

	sdp_uuid16_create(&bgscid, BROWSE_GRP_DESC_SVCLASS_ID);
	browselist = sdp_list_append(0, &bgscid);
	sdp_set_service_classes(browse, browselist);
	sdp_list_free(browselist, 0);

	sdp_uuid16_create(&pbgid, PUBLIC_BROWSE_GROUP);
	sdp_set_group_id(browse, pbgid);
}

/*
 * The SDP server must present its own service record to
 * the service repository. This can be accessed by service
 * discovery clients. This method constructs a service record
 * and stores it in the repository
 */
static void register_server_service(void)
{
	int i;
	sdp_list_t *classIDList, *browseList;
	sdp_list_t *access_proto = 0;
	uuid_t l2cap, classID, browseGroupId, sdpSrvUUID;
	void **versions, **versionDTDs;
	uint8_t dtd;
	uint16_t version, port;
	sdp_data_t *pData, *port_data, *version_data;
	sdp_list_t *pd, *seq;

	server = sdp_record_alloc();
	server->pattern = NULL;

	/* Force the record to be SDP_SERVER_RECORD_HANDLE */
	server->handle = SDP_SERVER_RECORD_HANDLE;

	sdp_record_add(server);
	sdp_attr_add(server, SDP_ATTR_RECORD_HANDLE, sdp_data_alloc(SDP_UINT32, &server->handle));

	/*
	 * Add all attributes to service record. (No need to commit since we 
	 * are the server and this record is already in the database.)
	 */
	add_lang_attr(server);
	sdp_set_info_attr(server, "SDP Server", "BlueZ", "Bluetooth service discovery server");

	sdp_uuid16_create(&classID, SDP_SERVER_SVCLASS_ID);
	classIDList = sdp_list_append(0, &classID);
	sdp_set_service_classes(server, classIDList);
	sdp_list_free(classIDList, 0);

	/*
	 * Set the version numbers supported, these are passed as arguments
	 * to the server on command line. Now defaults to 1.0
	 * Build the version number sequence first
	 */
	versions = (void **)malloc(sdpServerVnumEntries * sizeof(void *));
	versionDTDs = (void **)malloc(sdpServerVnumEntries * sizeof(void *));
	dtd = SDP_UINT16;
	for (i = 0; i < sdpServerVnumEntries; i++) {
		uint16_t *version = (uint16_t *)malloc(sizeof(uint16_t));
		*version = sdpVnumArray[i].major;
		*version = (*version << 8);
		*version |= sdpVnumArray[i].minor;
		versions[i] = version;
		versionDTDs[i] = &dtd;
	}
	pData = sdp_seq_alloc(versionDTDs, versions, sdpServerVnumEntries);
	for (i = 0; i < sdpServerVnumEntries; i++)
		free(versions[i]);
	free(versions);
	free(versionDTDs);
	sdp_attr_add(server, SDP_ATTR_VERSION_NUM_LIST, pData);

	sdp_uuid16_create(&sdpSrvUUID, SDP_UUID);
	sdp_set_service_id(server, sdpSrvUUID);

	sdp_uuid16_create(&l2cap, L2CAP_UUID);
	pd = sdp_list_append(0, &l2cap);
	port = SDP_PSM;
	port_data = sdp_data_alloc(SDP_UINT16, &port);
	pd = sdp_list_append(pd, port_data);
	version = 1;
	version_data = sdp_data_alloc(SDP_UINT16, &version);
	pd = sdp_list_append(pd, version_data);
	seq = sdp_list_append(0, pd);

	access_proto = sdp_list_append(0, seq);
	sdp_set_access_protos(server, access_proto);
	sdp_list_free(access_proto, free);
	sdp_data_free(port_data);
	sdp_data_free(version_data);
	sdp_list_free(pd, 0);

	sdp_uuid16_create(&browseGroupId, PUBLIC_BROWSE_GROUP);
	browseList = sdp_list_append(0, &browseGroupId);
	sdp_set_browse_groups(server, browseList);
	sdp_list_free(browseList, 0);

	update_db_timestamp();
}

/*
 * SDP server initialization on startup includes creating the
 * l2cap and unix sockets over which discovery and registration clients
 * access us respectively
 */
int init_server(int master)
{
	struct sockaddr_l2 l2addr;
	struct sockaddr_un unaddr;

	/* Register the public browse group root */
	register_public_browse_group();

	/* Register the SDP server's service record */
	register_server_service();

	/* Create L2CAP socket */
	l2cap_sock = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP);
	if (l2cap_sock == -1) {
		SDPERR("opening L2CAP socket: %s", strerror(errno));
		return -1;
	}

	l2addr.l2_bdaddr = *BDADDR_ANY;
	l2addr.l2_family = AF_BLUETOOTH;
	l2addr.l2_psm    = htobs(SDP_PSM);
	if (0 > bind(l2cap_sock, (struct sockaddr *)&l2addr, sizeof(l2addr))) {
		SDPERR("binding L2CAP socket: %s", strerror(errno));
		return -1;
	}

	if (master) {
		int opt = L2CAP_LM_MASTER;
		if (0 > setsockopt(l2cap_sock, SOL_L2CAP, L2CAP_LM, &opt, sizeof(opt))) {
			SDPERR("setsockopt: %s", strerror(errno));
			return -1;
		}
	}
	listen(l2cap_sock, 5);
	FD_SET(l2cap_sock, &active_fdset);
	active_maxfd = l2cap_sock;

	/* Create local Unix socket */
	unix_sock = socket(PF_UNIX, SOCK_STREAM, 0);
	if (unix_sock == -1) {
		SDPERR("opening UNIX socket: %s", strerror(errno));
		return -1;
	}
	unaddr.sun_family = AF_UNIX;
	strcpy(unaddr.sun_path, SDP_UNIX_PATH);
	unlink(unaddr.sun_path);
	if (0 > bind(unix_sock, (struct sockaddr *)&unaddr, sizeof(unaddr))) {
		SDPERR("binding UNIX socket: %s", strerror(errno));
		return -1;
	}
	listen(unix_sock, 5);
	FD_SET(unix_sock, &active_fdset);
	active_maxfd = unix_sock;
	chmod(SDP_UNIX_PATH, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
	return 0;
}

void sig_term(int sig)
{
	SDPINF("terminating... \n");
	sdp_svcdb_reset();
	close(l2cap_sock);
	close(unix_sock);
	exit(0);
}

int become_daemon(void)
{
	int fd;

	if (getppid() != 1) {
		signal(SIGTTOU, SIG_IGN);
		signal(SIGTTIN, SIG_IGN);
		signal(SIGTSTP, SIG_IGN);
		if (fork())
			return 0;
		setsid();
	}
	for (fd = 0; fd < 3; fd++)
		close(fd);

	chdir("/");
	return 1;
}

static inline void handle_request(int sk, char *data, int len)
{
	struct sockaddr_l2 sa;
	int 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;
		size = sizeof(lo);
		getsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &lo, &size);
		req.bdaddr = sa.l2_bdaddr;
		req.mtu    = lo.omtu;
		req.local  = 0;
	} else {
		req.bdaddr = *BDADDR_LOCAL;
		req.mtu    = 2048;
		req.local  = 1;
	}
	req.sock = sk;
	req.buf  = data;
	req.len  = len;
	process_request(&req);
}

static void close_sock(int fd, int r)
{
	if (r < 0)
		SDPERR("Read error: %s", strerror(errno));
	FD_CLR(fd, &active_fdset);
	close(fd);
	sdp_svcdb_collect_all(fd);
	if (fd == active_maxfd)
		active_maxfd--;
}

static void check_active(fd_set *mask, int num)
{
	sdp_pdu_hdr_t hdr;
	int size, fd, count, r;
	char *buf;

	for (fd = 0, count = 0; fd <= active_maxfd && count < num; fd++) {
		if (fd == l2cap_sock || fd == unix_sock || !FD_ISSET(fd, mask))
			continue;

		count++;

		r = recv(fd, (void *)&hdr, sizeof(sdp_pdu_hdr_t), MSG_PEEK);
		if (r <= 0) {
			close_sock(fd, r);
			continue;
		}
	       
		size = sizeof(sdp_pdu_hdr_t) + ntohs(hdr.plen);
		buf = malloc(size);
		if (!buf)
			continue;
		
		r = recv(fd, buf, size, 0);
		if (r <= 0)
			close_sock(fd, r);
		else
			handle_request(fd, buf, r);       
	}
}

void usage(void)
{
	printf("sdpd version %s\n", VERSION);
	printf("Usage:\n"
		"sdpd [-n] [-m]\n"
	);
}

static struct option main_options[] = {
        {"help", 0,0, 'h'},
        {"nodaemon",  0,0, 'n'},
        {"master",  0,0, 'm'},
        {0, 0, 0, 0}
};

int main(int argc, char **argv)
{
	int daemon = 1;
	int master = 0;
	int opt;

	while ((opt = getopt_long(argc, argv, "nm", main_options, NULL)) != -1)
		switch (opt) {
		case 'n':
			daemon = 0;
			break;
		case 'm':
			master = 1;
			break;
		default:
			usage();
			exit(0);
		}
	openlog("sdpd", LOG_PID | LOG_NDELAY, LOG_DAEMON);
	
	if (daemon && !become_daemon())
		return 0;

	argc -= optind;
	argv += optind;

	if (init_server(master) < 0) {
		SDPERR("Server initialization failed");
		return -1;
	}

	SDPINF("sdpd v%s started", VERSION);

	signal(SIGINT,  sig_term);
	signal(SIGTERM, sig_term);
	signal(SIGABRT, sig_term);
	signal(SIGQUIT, sig_term);
	signal(SIGPIPE, SIG_IGN);

	for (;;) {
		int num, nfd;
		fd_set mask;

		FD_ZERO(&mask);
		mask = active_fdset;

		num = select(active_maxfd + 1, &mask, NULL, NULL, NULL);
		if (num <= 0) {
			SDPDBG("Select error:%s", strerror(errno));
			goto exit;
		}

		if (FD_ISSET(l2cap_sock, &mask)) {
			/* New L2CAP connection  */
			struct sockaddr_l2 caddr;
			socklen_t len = sizeof(caddr);

			nfd = accept(l2cap_sock, (struct sockaddr *)&caddr, &len);
			if (nfd >= 0) {
				if (nfd > active_maxfd)
					active_maxfd = nfd;
				FD_SET(nfd, &active_fdset);
			}
		} else if (FD_ISSET(unix_sock, &mask)) {
			/* New unix connection */
			struct sockaddr_un caddr;
			socklen_t len = sizeof(caddr);

			nfd = accept(unix_sock, (struct sockaddr *)&caddr, &len);
			if (nfd != -1) {
				if (nfd > active_maxfd)
					active_maxfd = nfd;
				FD_SET(nfd, &active_fdset);
			}
		} else
			check_active(&mask, num);
	}
exit:
	sdp_svcdb_reset();
	return 0;
}