xref: /src/lib/libc/yp/yplib.c

/*	$NetBSD: yplib.c,v 1.20 1996/05/14 23:37:33 jtc Exp $	 */

/*
 * Copyright (c) 1992, 1993 Theo de Raadt <deraadt (at) fsa.ca>
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Theo de Raadt.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char rcsid[] = "$NetBSD: yplib.c,v 1.20 1996/05/14 23:37:33 jtc Exp $";
#endif

#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <rpc/rpc.h>
#include <rpc/xdr.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>

#define BINDINGDIR	"/var/yp/binding"
#define YPBINDLOCK	"/var/run/ypbind.lock"
#define YPMATCHCACHE

struct dom_binding *_ypbindlist;
static char _yp_domain[MAXHOSTNAMELEN];
int _yplib_timeout = 10;

static bool_t ypmatch_add __P((const char *, const char *, int, char *, int));
static bool_t ypmatch_find __P((const char *, const char *, int, const char **,
				int *));
void _yp_unbind __P((struct dom_binding *));

#ifdef YPMATCHCACHE
int _yplib_cache = 5;

static struct ypmatch_ent {
	struct ypmatch_ent 	*next;
	char     		*map, *key;
	char           		*val;
	int             	 keylen, vallen;
	time_t          	 expire_t;
} *ypmc;

static bool_t
ypmatch_add(map, key, keylen, val, vallen)
	const char     *map;
	const char     *key;
	int             keylen;
	char           *val;
	int             vallen;
{
	struct ypmatch_ent *ep;
	time_t t;

	(void)time(&t);

	for (ep = ypmc; ep; ep = ep->next)
		if (ep->expire_t < t)
			break;
	if (ep == NULL) {
		if ((ep = malloc(sizeof *ep)) == NULL)
			return 0;
		(void)memset(ep, 0, sizeof *ep);
		if (ypmc)
			ep->next = ypmc;
		ypmc = ep;
	}

	if (ep->key) {
		free(ep->key);
		ep->key = NULL;
	}
	if (ep->val) {
		free(ep->val);
		ep->val = NULL;
	}

	if ((ep->key = malloc(keylen)) == NULL)
		return 0;

	if ((ep->val = malloc(vallen)) == NULL) {
		free(ep->key);
		ep->key = NULL;
		return 0;
	}

	ep->keylen = keylen;
	ep->vallen = vallen;

	(void)memcpy(ep->key, key, ep->keylen);
	(void)memcpy(ep->val, val, ep->vallen);

	if (ep->map) {
		if (strcmp(ep->map, map)) {
			free(ep->map);
			if ((ep->map = strdup(map)) == NULL)
				return 0;
		}
	} else {
		if ((ep->map = strdup(map)) == NULL)
			return 0;
	}

	ep->expire_t = t + _yplib_cache;
	return 1;
}

static bool_t
ypmatch_find(map, key, keylen, val, vallen)
	const char     *map;
	const char     *key;
	int             keylen;
	const char    **val;
	int            *vallen;
{
	struct ypmatch_ent *ep;
	time_t          t;

	if (ypmc == NULL)
		return 0;

	(void) time(&t);

	for (ep = ypmc; ep; ep = ep->next) {
		if (ep->keylen != keylen)
			continue;
		if (strcmp(ep->map, map))
			continue;
		if (memcmp(ep->key, key, keylen))
			continue;
		if (t > ep->expire_t)
			continue;

		*val = ep->val;
		*vallen = ep->vallen;
		return 1;
	}
	return 0;
}
#endif

int
_yp_dobind(dom, ypdb)
	const char     *dom;
	struct dom_binding **ypdb;
{
	static int      pid = -1;
	char            path[MAXPATHLEN];
	struct dom_binding *ysd, *ysd2;
	struct ypbind_resp ypbr;
	struct timeval  tv;
	struct sockaddr_in clnt_sin;
	int             clnt_sock, fd, gpid;
	CLIENT         *client;
	int             new = 0, r;
	int             count = 0;

	/*
	 * test if YP is running or not
	 */
	if ((fd = open(YPBINDLOCK, O_RDONLY)) == -1)
		return YPERR_YPBIND;
	if (!(flock(fd, LOCK_EX | LOCK_NB) == -1 && errno == EWOULDBLOCK)) {
		(void)close(fd);
		return YPERR_YPBIND;
	}
	(void)close(fd);

	gpid = getpid();
	if (!(pid == -1 || pid == gpid)) {
		ysd = _ypbindlist;
		while (ysd) {
			if (ysd->dom_client)
				clnt_destroy(ysd->dom_client);
			ysd2 = ysd->dom_pnext;
			free(ysd);
			ysd = ysd2;
		}
		_ypbindlist = NULL;
	}
	pid = gpid;

	if (ypdb != NULL)
		*ypdb = NULL;

	if (dom == NULL || strlen(dom) == 0)
		return YPERR_BADARGS;

	for (ysd = _ypbindlist; ysd; ysd = ysd->dom_pnext)
		if (strcmp(dom, ysd->dom_domain) == 0)
			break;
	if (ysd == NULL) {
		if ((ysd = malloc(sizeof *ysd)) == NULL)
			return YPERR_YPERR;
		(void)memset(ysd, 0, sizeof *ysd);
		ysd->dom_socket = -1;
		ysd->dom_vers = 0;
		new = 1;
	}
again:
	if (ysd->dom_vers == 0) {
		(void) snprintf(path, sizeof(path), "%s/%s.%d",
				BINDINGDIR, dom, 2);
		if ((fd = open(path, O_RDONLY)) == -1) {
			/*
			 * no binding file, YP is dead, or not yet fully
			 * alive.
			 */
			goto trynet;
		}
		if (flock(fd, LOCK_EX | LOCK_NB) == -1 &&
		    errno == EWOULDBLOCK) {
			struct iovec    iov[2];
			struct ypbind_resp ybr;
			u_short         ypb_port;
			struct ypbind_binding *bn;

			iov[0].iov_base = (caddr_t) & ypb_port;
			iov[0].iov_len = sizeof ypb_port;
			iov[1].iov_base = (caddr_t) & ybr;
			iov[1].iov_len = sizeof ybr;

			r = readv(fd, iov, 2);
			if (r != iov[0].iov_len + iov[1].iov_len) {
				(void)close(fd);
				ysd->dom_vers = -1;
				goto again;
			}
			(void)memset(&ysd->dom_server_addr, 0,
				     sizeof ysd->dom_server_addr);
			ysd->dom_server_addr.sin_len =
				sizeof(struct sockaddr_in);
			ysd->dom_server_addr.sin_family = AF_INET;
			bn = &ybr.ypbind_respbody.ypbind_bindinfo;
			ysd->dom_server_addr.sin_port =
				bn->ypbind_binding_port;

			ysd->dom_server_addr.sin_addr =
				bn->ypbind_binding_addr;

			ysd->dom_server_port = ysd->dom_server_addr.sin_port;
			(void)close(fd);
			goto gotit;
		} else {
			/* no lock on binding file, YP is dead. */
			(void)close(fd);
			if (new)
				free(ysd);
			return YPERR_YPBIND;
		}
	}
trynet:
	if (ysd->dom_vers == -1 || ysd->dom_vers == 0) {
		struct ypbind_binding *bn;
		(void)memset(&clnt_sin, 0, sizeof clnt_sin);
		clnt_sin.sin_len = sizeof(struct sockaddr_in);
		clnt_sin.sin_family = AF_INET;
		clnt_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);

		clnt_sock = RPC_ANYSOCK;
		client = clnttcp_create(&clnt_sin, YPBINDPROG, YPBINDVERS,
					&clnt_sock, 0, 0);
		if (client == NULL) {
			clnt_pcreateerror("clnttcp_create");
			if (new)
				free(ysd);
			return YPERR_YPBIND;
		}
		tv.tv_sec = _yplib_timeout;
		tv.tv_usec = 0;
		r = clnt_call(client, YPBINDPROC_DOMAIN, xdr_domainname,
			      dom, xdr_ypbind_resp, &ypbr, tv);
		if (r != RPC_SUCCESS) {
			if (new == 0 || count)
				fprintf(stderr,
		    "YP server for domain %s not responding, still trying\n",
					dom);
			count++;
			clnt_destroy(client);
			ysd->dom_vers = -1;
			goto again;
		}
		clnt_destroy(client);

		(void)memset(&ysd->dom_server_addr, 0,
			     sizeof ysd->dom_server_addr);
		ysd->dom_server_addr.sin_len = sizeof(struct sockaddr_in);
		ysd->dom_server_addr.sin_family = AF_INET;
		bn = &ypbr.ypbind_respbody.ypbind_bindinfo;
		ysd->dom_server_addr.sin_port =
			bn->ypbind_binding_port;
		ysd->dom_server_addr.sin_addr.s_addr =
			bn->ypbind_binding_addr.s_addr;
		ysd->dom_server_port =
			bn->ypbind_binding_port;
gotit:
		ysd->dom_vers = YPVERS;
		(void)strcpy(ysd->dom_domain, dom);
	}
	tv.tv_sec = _yplib_timeout / 2;
	tv.tv_usec = 0;
	if (ysd->dom_client)
		clnt_destroy(ysd->dom_client);
	ysd->dom_socket = RPC_ANYSOCK;
	ysd->dom_client = clntudp_create(&ysd->dom_server_addr,
				      YPPROG, YPVERS, tv, &ysd->dom_socket);
	if (ysd->dom_client == NULL) {
		clnt_pcreateerror("clntudp_create");
		ysd->dom_vers = -1;
		goto again;
	}
	if (fcntl(ysd->dom_socket, F_SETFD, 1) == -1)
		perror("fcntl: F_SETFD");

	if (new) {
		ysd->dom_pnext = _ypbindlist;
		_ypbindlist = ysd;
	}
	if (ypdb != NULL)
		*ypdb = ysd;
	return 0;
}

void
_yp_unbind(ypb)
	struct dom_binding *ypb;
{
	clnt_destroy(ypb->dom_client);
	ypb->dom_client = NULL;
	ypb->dom_socket = -1;
}

int
yp_bind(dom)
	const char     *dom;
{
	return _yp_dobind(dom, NULL);
}

void
yp_unbind(dom)
	const char     *dom;
{
	struct dom_binding *ypb, *ypbp;

	ypbp = NULL;
	for (ypb = _ypbindlist; ypb; ypb = ypb->dom_pnext) {
		if (strcmp(dom, ypb->dom_domain) == 0) {
			clnt_destroy(ypb->dom_client);
			if (ypbp)
				ypbp->dom_pnext = ypb->dom_pnext;
			else
				_ypbindlist = ypb->dom_pnext;
			free(ypb);
			return;
		}
		ypbp = ypb;
	}
	return;
}

int
yp_match(indomain, inmap, inkey, inkeylen, outval, outvallen)
	const char     *indomain;
	const char     *inmap;
	const char     *inkey;
	int             inkeylen;
	char          **outval;
	int            *outvallen;
{
	struct dom_binding *ysd;
	struct ypresp_val yprv;
	struct timeval  tv;
	struct ypreq_key yprk;
	int             r;

	*outval = NULL;
	*outvallen = 0;

again:
	if (_yp_dobind(indomain, &ysd) != 0)
		return YPERR_DOMAIN;

#ifdef YPMATCHCACHE
	if (!strcmp(_yp_domain, indomain) && ypmatch_find(inmap, inkey,
			 inkeylen, &yprv.valdat.dptr, &yprv.valdat.dsize)) {
		*outvallen = yprv.valdat.dsize;
		if ((*outval = malloc(*outvallen + 1)) == NULL)
			return YPERR_YPERR;
		(void)memcpy(*outval, yprv.valdat.dptr, *outvallen);
		(*outval)[*outvallen] = '\0';
		return 0;
	}
#endif

	tv.tv_sec = _yplib_timeout;
	tv.tv_usec = 0;

	yprk.domain = indomain;
	yprk.map = inmap;
	yprk.keydat.dptr = (char *) inkey;
	yprk.keydat.dsize = inkeylen;

	memset(&yprv, 0, sizeof yprv);

	r = clnt_call(ysd->dom_client, YPPROC_MATCH,
		      xdr_ypreq_key, &yprk, xdr_ypresp_val, &yprv, tv);
	if (r != RPC_SUCCESS) {
		clnt_perror(ysd->dom_client, "yp_match: clnt_call");
		ysd->dom_vers = -1;
		goto again;
	}
	if (!(r = ypprot_err(yprv.status))) {
		*outvallen = yprv.valdat.dsize;
		if ((*outval = malloc(*outvallen + 1)) == NULL)
			return YPERR_YPERR;
		(void)memcpy(*outval, yprv.valdat.dptr, *outvallen);
		(*outval)[*outvallen] = '\0';
#ifdef YPMATCHCACHE
		if (strcmp(_yp_domain, indomain) == 0)
			if (!ypmatch_add(inmap, inkey, inkeylen,
					 *outval, *outvallen))
				r = RPC_SYSTEMERROR;
#endif
	}
	xdr_free(xdr_ypresp_val, (char *) &yprv);
	_yp_unbind(ysd);
	return r;
}

int
yp_get_default_domain(domp)
	char          **domp;
{
	*domp = NULL;
	if (_yp_domain[0] == '\0')
		if (getdomainname(_yp_domain, sizeof _yp_domain))
			return YPERR_NODOM;
	*domp = _yp_domain;
	return 0;
}

int
yp_first(indomain, inmap, outkey, outkeylen, outval, outvallen)
	const char     *indomain;
	const char     *inmap;
	char          **outkey;
	int            *outkeylen;
	char          **outval;
	int            *outvallen;
{
	struct ypresp_key_val yprkv;
	struct ypreq_nokey yprnk;
	struct dom_binding *ysd;
	struct timeval  tv;
	int             r;

	*outkey = *outval = NULL;
	*outkeylen = *outvallen = 0;

again:
	if (_yp_dobind(indomain, &ysd) != 0)
		return YPERR_DOMAIN;

	tv.tv_sec = _yplib_timeout;
	tv.tv_usec = 0;

	yprnk.domain = indomain;
	yprnk.map = inmap;
	(void)memset(&yprkv, 0, sizeof yprkv);

	r = clnt_call(ysd->dom_client, YPPROC_FIRST,
		   xdr_ypreq_nokey, &yprnk, xdr_ypresp_key_val, &yprkv, tv);
	if (r != RPC_SUCCESS) {
		clnt_perror(ysd->dom_client, "yp_first: clnt_call");
		ysd->dom_vers = -1;
		goto again;
	}
	if (!(r = ypprot_err(yprkv.status))) {
		*outkeylen = yprkv.keydat.dsize;
		if ((*outkey = malloc(*outkeylen + 1)) == NULL)
			r = RPC_SYSTEMERROR;
		else {
			(void)memcpy(*outkey, yprkv.keydat.dptr, *outkeylen);
			(*outkey)[*outkeylen] = '\0';
		}
		*outvallen = yprkv.valdat.dsize;
		if ((*outval = malloc(*outvallen + 1)) == NULL)
			r = RPC_SYSTEMERROR;
		else {
			(void)memcpy(*outval, yprkv.valdat.dptr, *outvallen);
			(*outval)[*outvallen] = '\0';
		}
	}
	xdr_free(xdr_ypresp_key_val, (char *) &yprkv);
	_yp_unbind(ysd);
	return r;
}

int
yp_next(indomain, inmap, inkey, inkeylen, outkey, outkeylen, outval, outvallen)
	const char     *indomain;
	const char     *inmap;
	const char     *inkey;
	int             inkeylen;
	char          **outkey;
	int            *outkeylen;
	char          **outval;
	int            *outvallen;
{
	struct ypresp_key_val yprkv;
	struct ypreq_key yprk;
	struct dom_binding *ysd;
	struct timeval  tv;
	int             r;

	*outkey = *outval = NULL;
	*outkeylen = *outvallen = 0;

again:
	if (_yp_dobind(indomain, &ysd) != 0)
		return YPERR_DOMAIN;

	tv.tv_sec = _yplib_timeout;
	tv.tv_usec = 0;

	yprk.domain = indomain;
	yprk.map = inmap;
	yprk.keydat.dptr = inkey;
	yprk.keydat.dsize = inkeylen;
	(void)memset(&yprkv, 0, sizeof yprkv);

	r = clnt_call(ysd->dom_client, YPPROC_NEXT,
		      xdr_ypreq_key, &yprk, xdr_ypresp_key_val, &yprkv, tv);
	if (r != RPC_SUCCESS) {
		clnt_perror(ysd->dom_client, "yp_next: clnt_call");
		ysd->dom_vers = -1;
		goto again;
	}
	if (!(r = ypprot_err(yprkv.status))) {
		*outkeylen = yprkv.keydat.dsize;
		if ((*outkey = malloc(*outkeylen + 1)) == NULL)
			r = RPC_SYSTEMERROR;
		else {
			(void)memcpy(*outkey, yprkv.keydat.dptr, *outkeylen);
			(*outkey)[*outkeylen] = '\0';
		}
		*outvallen = yprkv.valdat.dsize;
		if ((*outval = malloc(*outvallen + 1)) == NULL)
			r = RPC_SYSTEMERROR;
		else {
			(void)memcpy(*outval, yprkv.valdat.dptr, *outvallen);
			(*outval)[*outvallen] = '\0';
		}
	}
	xdr_free(xdr_ypresp_key_val, (char *) &yprkv);
	_yp_unbind(ysd);
	return r;
}

int
yp_maplist(indomain, outmaplist)
	const char     *indomain;
	struct ypmaplist **outmaplist;
{
	struct dom_binding *ysd;
	struct ypresp_maplist ypml;
	struct timeval  tv;
	int             r;

again:
	if (_yp_dobind(indomain, &ysd) != 0)
		return YPERR_DOMAIN;

	tv.tv_sec = _yplib_timeout;
	tv.tv_usec = 0;

	memset(&ypml, 0, sizeof ypml);

	r = clnt_call(ysd->dom_client, YPPROC_MAPLIST,
		   xdr_domainname, indomain, xdr_ypresp_maplist, &ypml, tv);
	if (r != RPC_SUCCESS) {
		clnt_perror(ysd->dom_client, "yp_maplist: clnt_call");
		ysd->dom_vers = -1;
		goto again;
	}
	*outmaplist = ypml.list;
	/* NO: xdr_free(xdr_ypresp_maplist, &ypml); */
	_yp_unbind(ysd);
	return ypprot_err(ypml.status);
}

int
ypprot_err(incode)
	unsigned int    incode;
{
	switch (incode) {
	case YP_TRUE:
		return 0;
	case YP_FALSE:
		return YPERR_YPBIND;
	case YP_NOMORE:
		return YPERR_NOMORE;
	case YP_NOMAP:
		return YPERR_MAP;
	case YP_NODOM:
		return YPERR_NODOM;
	case YP_NOKEY:
		return YPERR_KEY;
	case YP_BADOP:
		return YPERR_YPERR;
	case YP_BADDB:
		return YPERR_BADDB;
	case YP_YPERR:
		return YPERR_YPERR;
	case YP_BADARGS:
		return YPERR_BADARGS;
	case YP_VERS:
		return YPERR_VERS;
	}
	return YPERR_YPERR;
}

int
_yp_check(dom)
	char          **dom;
{
	char           *unused;

	if (_yp_domain[0] == '\0')
		if (yp_get_default_domain(&unused))
			return 0;

	if (dom)
		*dom = _yp_domain;

	if (yp_bind(_yp_domain) == 0)
		return 1;
	return 0;
}