gethostbynis.c

Newlib 嵌入式 C库 标准实现代码

/*-
 * Copyright (c) 1994, Garrett Wollman
 *
 * 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 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 REGENTS 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.
 */

#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/types.h>

#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include <nsswitch.h>
#ifdef YP
#include <rpc/rpc.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
#endif

#ifdef YP
static char *host_aliases[MAXALIASES];
static char hostaddr[MAXADDRS];
static char *host_addrs[2];

static struct hostent *
_gethostbynis(name, map, af)
	const char *name;
	char *map;
	int af;
{
	char *cp, **q;
	char *result;
	int resultlen,size;
	static struct hostent h;
	static char *domain = (char *)NULL;
	static char ypbuf[YPMAXRECORD + 2];

	switch(af) {
	case AF_INET:
		size = NS_INADDRSZ;
		break;
	default:
	case AF_INET6:
		size = NS_IN6ADDRSZ;
		errno = EAFNOSUPPORT;
		h_errno = NETDB_INTERNAL;
		return NULL;
	}

	if (domain == (char *)NULL)
		if (yp_get_default_domain (&domain)) {
			h_errno = NETDB_INTERNAL;
			return ((struct hostent *)NULL);
		}

	if (yp_match(domain, map, name, strlen(name), &result, &resultlen)) {
		h_errno = HOST_NOT_FOUND;
		return ((struct hostent *)NULL);
	}

	/* avoid potential memory leak */
	bcopy((char *)result, (char *)&ypbuf, resultlen);
	ypbuf[resultlen] = '\0';
	free(result);
	result = (char *)&ypbuf;

	if ((cp = index(result, '\n')))
		*cp = '\0';

	cp = strpbrk(result, " \t");
	*cp++ = '\0';
	h.h_addr_list = host_addrs;
	h.h_addr = hostaddr;
	*((u_long *)h.h_addr) = inet_addr(result);
	h.h_length = size;
	h.h_addrtype = AF_INET;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	h.h_name = cp;
	q = h.h_aliases = host_aliases;
	cp = strpbrk(cp, " \t");
	if (cp != NULL)
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &host_aliases[MAXALIASES - 1])
			*q++ = cp;
		cp = strpbrk(cp, " \t");
		if (cp != NULL)
			*cp++ = '\0';
	}
	*q = NULL;
	return (&h);
}

static struct hostent *
_gethostbynis_r(name, map, af, hp, buffer, buflen, herr)
	const char *name;
	char *map;
	int af;
        struct hostent *hp;
        char *buffer;
        int buflen;
        int *herr;
{
	char *cp, **q;
	char *result;
	int resultlen,size;
	char *domain = (char *)NULL;

	switch(af) {
	case AF_INET:
		size = NS_INADDRSZ;
		break;
	default:
	case AF_INET6:
		size = NS_IN6ADDRSZ;
		errno = EAFNOSUPPORT;
		*herr = NETDB_INTERNAL;
		return NULL;
	}

	if (domain == (char *)NULL)
		if (yp_get_default_domain (&domain)) {
			*herr = NETDB_INTERNAL;
			return ((struct hostent *)NULL);
		}

	if (yp_match(domain, map, name, strlen(name), &result, &resultlen)) {
		*herr = HOST_NOT_FOUND;
		return ((struct hostent *)NULL);
	}

	/* avoid potential memory leak */
	bcopy((char *)result, buffer, resultlen);
	buffer[resultlen] = '\0';
	free(result);
	result = buffer;

	if ((cp = index(result, '\n')))
		*cp = '\0';

	cp = strpbrk(result, " \t");
	*cp++ = '\0';
	*((u_long *)hp->__host_addrs[0]) = inet_addr(result);
        hp->__host_addrs[1] = NULL;
	hp->h_addr_list = hp->__host_addrs;
	hp->h_addr = hp->__host_addrs[0];
	hp->h_length = size;
	hp->h_addrtype = AF_INET;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	hp->h_name = cp;
	q = hp->__host_aliases;
	cp = strpbrk(cp, " \t");
	if (cp != NULL)
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &hp->__host_aliases[MAXALIASES - 1])
			*q++ = cp;
		cp = strpbrk(cp, " \t");
		if (cp != NULL)
			*cp++ = '\0';
	}
        hp->h_aliases = hp->__host_aliases;
	*q = NULL;
	return (&hp);
}
#endif /* YP */

/* XXX _gethostbynisname/_gethostbynisaddr only used by getaddrinfo */
struct hostent *
_gethostbynisname(const char *name, int af)
{
#ifdef YP
	return _gethostbynis(name, "hosts.byname", af);
#else
	return NULL;
#endif
}

struct hostent *
_gethostbynisaddr(const char *addr, int len, int af)
{
#ifdef YP
	return _gethostbynis(inet_ntoa(*(struct in_addr *)addr), 
			     "hosts.byaddr", af);
#else
	return NULL;
#endif
}


int
_nis_gethostbyname(void *rval, void *cb_data, va_list ap)
{
#ifdef YP
	const char *name;
	int af;
        struct hostent *resultbuf;
        char *buf;
        int buflen;
        int *herr;

	name = va_arg(ap, const char *);
	af = va_arg(ap, int);
        resultbuf = va_arg(ap, struct hostent *);
        buf = va_arg(ap, char *);
        buflen = va_arg(ap, int);
        herr = va_arg(ap, int *);

        *(struct hostent **)rval = _gethostbynis_r(name, "hosts.byname", af, resultbuf, buf, buflen, herr);

        return (*(struct hostent **)rval != NULL) ? NS_SUCCESS : NS_NOTFOUND;
#else
	return NS_UNAVAIL;
#endif
}

int
_nis_gethostbyaddr(void *rval, void *cb_data, va_list ap)
{
#ifdef YP
	const char *addr;
	int len;
	int af;
        struct hostent *resultbuf;
        char *buf;
        int buflen;
        int *herr;

	addr = va_arg(ap, const char *);
	len = va_arg(ap, int);
	af = va_arg(ap, int);
        resultbuf = va_arg(ap, struct hostent *);
        buf = va_arg(ap, char *);
        buflen = va_arg(ap, int);
        herr = va_arg(ap, int *);

	*(struct hostent **)rval = _gethostbynis_r(inet_ntoa(*(struct in_addr *)addr),"hosts.byaddr", af);
        return (*(struct hostent **)rval != NULL) ? NS_SUCCESS : NS_NOTFOUND;
#else
	return NS_UNAVAIL;
#endif
}