/*
 * bluetooth.c
 */

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2001-2009 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: bluetooth.c,v 1.3 2003/05/20 23:04:30 max Exp $
 */
#define L2CAP_SOCKET_CHECKED
#include <bluetooth.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define _PATH_BT_HOSTS          "/etc/bluetooth/hosts"
#define _PATH_BT_PROTOCOLS      "/etc/bluetooth/protocols"
#define MAXALIASES               35

static FILE             *hostf = NULL;
static int               host_stayopen = 0;
static struct hostent    host;
static bdaddr_t          host_addr;
static char             *host_addr_ptrs[2];
static char             *host_aliases[MAXALIASES];

static FILE             *protof = NULL;
static int               proto_stayopen = 0;
static struct protoent   proto;
static char             *proto_aliases[MAXALIASES];

static char              buf[BUFSIZ + 1];

static int bt_hex_byte   (char const *str);
static int bt_hex_nibble (char nibble);

struct hostent *
bt_gethostbyname(char const *name)
{
        struct hostent  *p;
        char            **cp;

        bt_sethostent(host_stayopen);
        while ((p = bt_gethostent()) != NULL) {
                if (strcasecmp(p->h_name, name) == 0)
                        break;
                for (cp = p->h_aliases; *cp != NULL; cp++)
                        if (strcasecmp(*cp, name) == 0)
                                goto found;
        }
found:
        bt_endhostent();

        return (p);
}

struct hostent *
bt_gethostbyaddr(char const *addr, int len, int type)
{
        struct hostent  *p;

        if (type != AF_BLUETOOTH || len != sizeof(bdaddr_t)) {
                h_errno = NO_RECOVERY;
                return (NULL);
        }

        bt_sethostent(host_stayopen);
        while ((p = bt_gethostent()) != NULL)
                if (p->h_addrtype == type && bcmp(p->h_addr, addr, len) == 0)
                        break;
        bt_endhostent();

        return (p);
}

struct hostent *
bt_gethostent(void)
{
        char    *p, *cp, **q;

        if (hostf == NULL)
                hostf = fopen(_PATH_BT_HOSTS, "r");

        if (hostf == NULL) {
                h_errno = NETDB_INTERNAL;
                return (NULL);
        }
again:
        if ((p = fgets(buf, sizeof(buf), hostf)) == NULL) {
                h_errno = HOST_NOT_FOUND;
                return (NULL);
        }
        if (*p == '#')
                goto again;
        if ((cp = strpbrk(p, "#\n")) == NULL)
                goto again;
        *cp = 0;
        if ((cp = strpbrk(p, " \t")) == NULL)
                goto again;
        *cp++ = 0;
        if (bt_aton(p, &host_addr) == 0) 
                goto again;
        host_addr_ptrs[0] = (char *) &host_addr;
        host_addr_ptrs[1] = NULL;
        host.h_addr_list = host_addr_ptrs;
        host.h_length = sizeof(host_addr);
        host.h_addrtype = AF_BLUETOOTH;
        while (*cp == ' ' || *cp == '\t')
                cp++;
        host.h_name = cp;
        q = host.h_aliases = host_aliases;
        if ((cp = strpbrk(cp, " \t")) != NULL)
                *cp++ = 0;
        while (cp != NULL && *cp != 0) {
                if (*cp == ' ' || *cp == '\t') {
                        cp++;
                        continue;
                }
                if (q < &host_aliases[MAXALIASES - 1])
                        *q++ = cp;
                if ((cp = strpbrk(cp, " \t")) != NULL)
                        *cp++ = 0;
        }
        *q = NULL;
        h_errno = NETDB_SUCCESS;

        return (&host);
}

void
bt_sethostent(int stayopen)
{
        if (hostf == NULL)
                hostf = fopen(_PATH_BT_HOSTS, "r");
        else
                rewind(hostf);

        host_stayopen = stayopen;
}

void
bt_endhostent(void)
{
        if (hostf != NULL && host_stayopen == 0) {
                (void) fclose(hostf);
                hostf = NULL;
        }
}

struct protoent *
bt_getprotobyname(char const *name)
{
        struct protoent  *p;
        char            **cp;

        bt_setprotoent(proto_stayopen);
        while ((p = bt_getprotoent()) != NULL) {
                if (strcmp(p->p_name, name) == 0)
                        break;
                for (cp = p->p_aliases; *cp != NULL; cp++)
                        if (strcmp(*cp, name) == 0)
                                goto found;
        }
found:
        bt_endprotoent();

        return (p);
}

struct protoent *
bt_getprotobynumber(int proto)
{
        struct protoent *p;

        bt_setprotoent(proto_stayopen);
        while ((p = bt_getprotoent()) != NULL)
                if (p->p_proto == proto)
                        break;
        bt_endprotoent();

        return (p);
}

struct protoent *
bt_getprotoent(void)
{
        char    *p, *cp, **q;

        if (protof == NULL)
                protof = fopen(_PATH_BT_PROTOCOLS, "r");

        if (protof == NULL)
                return (NULL);
again:
        if ((p = fgets(buf, sizeof(buf), protof)) == NULL)
                return (NULL);
        if (*p == '#')
                goto again;
        if ((cp = strpbrk(p, "#\n")) == NULL)
                goto again;
        *cp = '\0';
        proto.p_name = p;
        if ((cp = strpbrk(p, " \t")) == NULL)
                goto again;
        *cp++ = '\0';
        while (*cp == ' ' || *cp == '\t')
                cp++;
        if ((p = strpbrk(cp, " \t")) != NULL)
                *p++ = '\0';
        proto.p_proto = atoi(cp);
        q = proto.p_aliases = proto_aliases;
        if (p != NULL) {
                cp = p;
                while (cp != NULL && *cp != 0) {
                        if (*cp == ' ' || *cp == '\t') {
                                cp++;
                                continue;
                        }
                        if (q < &proto_aliases[MAXALIASES - 1])
                                *q++ = cp;
                        if ((cp = strpbrk(cp, " \t")) != NULL)
                                *cp++ = '\0';
                }
        }
        *q = NULL;

        return (&proto);
}

void
bt_setprotoent(int stayopen)
{
        if (protof == NULL)
                protof = fopen(_PATH_BT_PROTOCOLS, "r");
        else
                rewind(protof);

        proto_stayopen = stayopen;
}

void
bt_endprotoent(void)
{
        if (protof != NULL) {
                (void) fclose(protof);
                protof = NULL;
        }
}

char const *
bt_ntoa(bdaddr_t const *ba, char *str)
{
        static char     buffer[24];

        if (str == NULL)
                str = buffer;

        sprintf(str, "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x",
                ba->b[5], ba->b[4], ba->b[3], ba->b[2], ba->b[1], ba->b[0]);

        return (str);
}

int
bt_aton(char const *str, bdaddr_t *ba)
{
        int      i, b;
        char    *end = NULL;

        memset(ba, 0, sizeof(*ba));

        for (i = 5, end = strchr(str, ':');
             i > 0 && *str != '\0' && end != NULL;
             i --, str = end + 1, end = strchr(str, ':')) {
                switch (end - str) {
                case 1:
                        b = bt_hex_nibble(str[0]);
                        break;

                case 2:
                        b = bt_hex_byte(str);
                        break;

                default:
                        b = -1;
                        break;
                }
                
                if (b < 0)
                        return (0);

                ba->b[i] = b;
        }

        if (i != 0 || end != NULL || *str == 0)
                return (0);

        switch (strlen(str)) {
        case 1:
                b = bt_hex_nibble(str[0]);
                break;

        case 2:
                b = bt_hex_byte(str);
                break;

        default:
                b = -1;
                break;
        }

        if (b < 0)
                return (0);

        ba->b[i] = b;

        return (1);
}

static int
bt_hex_byte(char const *str)
{
        int     n1, n2;

        if ((n1 = bt_hex_nibble(str[0])) < 0)
                return (-1);

        if ((n2 = bt_hex_nibble(str[1])) < 0)
                return (-1);

        return ((((n1 & 0x0f) << 4) | (n2 & 0x0f)) & 0xff);
}

static int
bt_hex_nibble(char nibble)
{
        if ('0' <= nibble && nibble <= '9')
                return (nibble - '0');

        if ('a' <= nibble && nibble <= 'f')
                return (nibble - 'a' + 0xa);

        if ('A' <= nibble && nibble <= 'F')
                return (nibble - 'A' + 0xa);

        return (-1);
}