getpublickey.c

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2009, Sun Microsystems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * - Redistributions of source code must retain the above copyright notice, 
 *   this list of conditions and the following disclaimer.
 * - 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.
 * - Neither the name of Sun Microsystems, Inc. nor the names of its 
 *   contributors may be used to endorse or promote products derived 
 *   from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
 */

/*
 * publickey.c
 * Copyright (C) 1986, Sun Microsystems, Inc.
 */

/*
 * Public key lookup routines
 */
#include "namespace.h"
#include <stdio.h>
#include <pwd.h>
#include <rpc/rpc.h>
#include <rpc/key_prot.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
#include <string.h>
#include <stdlib.h>
#include "un-namespace.h"

#define PKFILE "/etc/publickey"

/*
 * Hack to let ypserv/rpc.nisd use AUTH_DES.
 */
int (*__getpublickey_LOCAL)(const char *, char *) = 0;

/*
 * Get somebody's public key
 */
static int
__getpublickey_real(const char *netname, char *publickey)
{
	char lookup[3 * HEXKEYBYTES];
	char *p;

	if (publickey == NULL)
		return (0);
	if (!getpublicandprivatekey(netname, lookup))
		return (0);
	p = strchr(lookup, ':');
	if (p == NULL) {
		return (0);
	}
	*p = '\0';
	(void) strncpy(publickey, lookup, HEXKEYBYTES);
	publickey[HEXKEYBYTES] = '\0';
	return (1);
}

/*
 * reads the file /etc/publickey looking for a + to optionally go to the
 * yellow pages
 */

int
getpublicandprivatekey(const char *key, char *ret)
{
	char buf[1024];	/* big enough */
	char *res;
	FILE *fd;
	char *mkey;
	char *mval;

	fd = fopen(PKFILE, "r");
	if (fd == NULL)
		return (0);
	for (;;) {
		res = fgets(buf, sizeof(buf), fd);
		if (res == NULL) {
			fclose(fd);
			return (0);
		}
		if (res[0] == '#')
			continue;
		else if (res[0] == '+') {
#ifdef YP
			char *PKMAP = "publickey.byname";
			char *lookup;
			char *domain;
			int err;
			int len;

			err = yp_get_default_domain(&domain);
			if (err) {
				continue;
			}
			lookup = NULL;
			err = yp_match(domain, PKMAP, key, strlen(key), &lookup, &len);
			if (err) {
#ifdef DEBUG
				fprintf(stderr, "match failed error %d\n", err);
#endif
				continue;
			}
			lookup[len] = 0;
			strcpy(ret, lookup);
			fclose(fd);
			free(lookup);
			return (2);
#else /* YP */
#ifdef DEBUG
			fprintf(stderr,
"Bad record in %s '+' -- NIS not supported in this library copy\n", PKFILE);
#endif /* DEBUG */
			continue;
#endif /* YP */
		} else {
			mkey = strsep(&res, "\t ");
			if (mkey == NULL) {
				fprintf(stderr,
				"Bad record in %s -- %s", PKFILE, buf);
				continue;
			}
			do {
				mval = strsep(&res, " \t#\n");
			} while (mval != NULL && !*mval);
			if (mval == NULL) {
				fprintf(stderr,
			"Bad record in %s val problem - %s", PKFILE, buf);
				continue;
			}
			if (strcmp(mkey, key) == 0) {
				strcpy(ret, mval);
				fclose(fd);
				return (1);
			}
		}
	}
}

int getpublickey(const char *netname, char *publickey)
{
	if (__getpublickey_LOCAL != NULL)
		return(__getpublickey_LOCAL(netname, publickey));
	else
		return(__getpublickey_real(netname, publickey));
}