update.c revision 344746 
1/*
2 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3 * unrestricted use provided that this legend is included on all tape
4 * media and as a part of the software program in whole or part.  Users
5 * may copy or modify Sun RPC without charge, but are not authorized
6 * to license or distribute it to anyone else except as part of a product or
7 * program developed by the user or with the express written consent of
8 * Sun Microsystems, Inc.
9 *
10 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
11 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
12 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
13 *
14 * Sun RPC is provided with no support and without any obligation on the
15 * part of Sun Microsystems, Inc. to assist in its use, correction,
16 * modification or enhancement.
17 *
18 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
19 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
20 * OR ANY PART THEREOF.
21 *
22 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
23 * or profits or other special, indirect and consequential damages, even if
24 * Sun has been advised of the possibility of such damages.
25 *
26 * Sun Microsystems, Inc.
27 * 2550 Garcia Avenue
28 * Mountain View, California  94043
29 */
30
31#ifndef lint
32#if 0
33static	char sccsid[] = "@(#)update.c 1.2 91/03/11 Copyr 1986 Sun Micro";
34#endif
35static const char rcsid[] =
36  "$FreeBSD: stable/11/usr.sbin/rpc.ypupdated/update.c 344746 2019-03-04 03:30:39Z avos $";
37#endif /* not lint */
38
39/*
40 * Copyright (C) 1986, 1989, Sun Microsystems, Inc.
41 */
42
43/*
44 * Administrative tool to add a new user to the publickey database
45 */
46#include <stdio.h>
47#include <stdlib.h>
48#include <unistd.h>
49#include <rpc/rpc.h>
50#include <rpc/key_prot.h>
51#ifdef YP
52#include <rpcsvc/yp_prot.h>
53#include <rpcsvc/ypclnt.h>
54#include <sys/wait.h>
55#include <netdb.h>
56#endif	/* YP */
57#include <pwd.h>
58#include <string.h>
59#include <sys/resource.h>
60#include "ypupdated_extern.h"
61
62#ifdef YP
63#define	MAXMAPNAMELEN 256
64#else
65#define	YPOP_CHANGE 1			/* change, do not add */
66#define	YPOP_INSERT 2			/* add, do not change */
67#define	YPOP_DELETE 3			/* delete this entry */
68#define	YPOP_STORE  4			/* add, or change */
69#endif
70
71#ifdef YP
72static char SHELL[] = "/bin/sh";
73static char YPDBPATH[]="/var/yp";	/* This is defined but not used! */
74static char PKMAP[] = "publickey.byname";
75static char UPDATEFILE[] = "updaters";
76static char PKFILE[] = "/etc/publickey";
77#endif	/* YP */
78
79#ifdef YP
80static int _openchild(char *, FILE **, FILE **);
81
82/*
83 * Determine if requester is allowed to update the given map,
84 * and update it if so. Returns the yp status, which is zero
85 * if there is no access violation.
86 */
87int
88mapupdate(char *requester, char *mapname, u_int op, u_int keylen, char *key,
89    u_int datalen, char *data)
90{
91	char updater[MAXMAPNAMELEN + 40];
92	FILE *childargs;
93	FILE *childrslt;
94#ifdef WEXITSTATUS
95	int status;
96#else
97	union wait status;
98#endif
99	pid_t pid;
100	u_int yperrno;
101
102
103#ifdef DEBUG
104	printf("%s %s\n", key, data);
105#endif
106	(void)sprintf(updater, "make -s -f %s/%s %s", YPDBPATH, /* !!! */
107					UPDATEFILE, mapname);
108	pid = _openchild(updater, &childargs, &childrslt);
109	if (pid < 0) {
110		return (YPERR_YPERR);
111	}
112
113	/*
114	 * Write to child
115	 */
116	(void)fprintf(childargs, "%s\n", requester);
117	(void)fprintf(childargs, "%u\n", op);
118	(void)fprintf(childargs, "%u\n", keylen);
119	(void)fwrite(key, (int)keylen, 1, childargs);
120	(void)fprintf(childargs, "\n");
121	(void)fprintf(childargs, "%u\n", datalen);
122	(void)fwrite(data, (int)datalen, 1, childargs);
123	(void)fprintf(childargs, "\n");
124	(void)fclose(childargs);
125
126	/*
127	 * Read from child
128	 */
129	(void)fscanf(childrslt, "%d", &yperrno);
130	(void)fclose(childrslt);
131
132	(void)wait(&status);
133#ifdef WEXITSTATUS
134	if (WEXITSTATUS(status) != 0)
135#else
136	if (status.w_retcode != 0)
137#endif
138		return (YPERR_YPERR);
139	return (yperrno);
140}
141
142/*
143 * returns pid, or -1 for failure
144 */
145static int
146_openchild(char *command, FILE **fto, FILE **ffrom)
147{
148	int i;
149	pid_t pid;
150	int pdto[2];
151	int pdfrom[2];
152	char *com;
153	struct rlimit rl;
154
155	if (pipe(pdto) < 0) {
156		goto error1;
157	}
158	if (pipe(pdfrom) < 0) {
159		goto error2;
160	}
161	switch (pid = fork()) {
162	case -1:
163		goto error3;
164
165	case 0:
166		/*
167		 * child: read from pdto[0], write into pdfrom[1]
168		 */
169		(void)close(0);
170		(void)dup(pdto[0]);
171		(void)close(1);
172		(void)dup(pdfrom[1]);
173		getrlimit(RLIMIT_NOFILE, &rl);
174		for (i = rl.rlim_max - 1; i >= 3; i--) {
175			(void) close(i);
176		}
177		com = malloc((unsigned) strlen(command) + 6);
178		if (com == NULL) {
179			_exit(~0);
180		}
181		(void)sprintf(com, "exec %s", command);
182		execl(SHELL, basename(SHELL), "-c", com, (char *)NULL);
183		_exit(~0);
184
185	default:
186		/*
187		 * parent: write into pdto[1], read from pdfrom[0]
188		 */
189		*fto = fdopen(pdto[1], "w");
190		(void)close(pdto[0]);
191		*ffrom = fdopen(pdfrom[0], "r");
192		(void)close(pdfrom[1]);
193		break;
194	}
195	return (pid);
196
197	/*
198	 * error cleanup and return
199	 */
200error3:
201	(void)close(pdfrom[0]);
202	(void)close(pdfrom[1]);
203error2:
204	(void)close(pdto[0]);
205	(void)close(pdto[1]);
206error1:
207	return (-1);
208}
209
210static char *
211basename(char *path)
212{
213	char *p;
214
215	p = strrchr(path, '/');
216	if (p == NULL) {
217		return (path);
218	} else {
219		return (p + 1);
220	}
221}
222
223#else /* YP */
224
225static int match(char *, char *);
226
227/*
228 * Determine if requester is allowed to update the given map,
229 * and update it if so. Returns the status, which is zero
230 * if there is no access violation. This function updates
231 * the local file and then shuts up.
232 */
233int
234localupdate(char *name, char *filename, u_int op, u_int keylen __unused,
235    char *key, u_int datalen __unused, char *data)
236{
237	char line[256];
238	FILE *rf;
239	FILE *wf;
240	char *tmpname;
241	int err;
242
243	/*
244	 * Check permission
245	 */
246	if (strcmp(name, key) != 0) {
247		return (ERR_ACCESS);
248	}
249	if (strcmp(name, "nobody") == 0) {
250		/*
251		 * Can't change "nobody"s key.
252		 */
253		return (ERR_ACCESS);
254	}
255
256	/*
257	 * Open files
258	 */
259	tmpname = malloc(strlen(filename) + 4);
260	if (tmpname == NULL) {
261		return (ERR_MALLOC);
262	}
263	sprintf(tmpname, "%s.tmp", filename);
264	rf = fopen(filename, "r");
265	if (rf == NULL) {
266		err = ERR_READ;
267		goto cleanup;
268	}
269	wf = fopen(tmpname, "w");
270	if (wf == NULL) {
271		fclose(rf);
272		err = ERR_WRITE;
273		goto cleanup;
274	}
275	err = -1;
276	while (fgets(line, sizeof (line), rf)) {
277		if (err < 0 && match(line, name)) {
278			switch (op) {
279			case YPOP_INSERT:
280				err = ERR_KEY;
281				break;
282			case YPOP_STORE:
283			case YPOP_CHANGE:
284				fprintf(wf, "%s %s\n", key, data);
285				err = 0;
286				break;
287			case YPOP_DELETE:
288				/* do nothing */
289				err = 0;
290				break;
291			}
292		} else {
293			fputs(line, wf);
294		}
295	}
296	if (err < 0) {
297		switch (op) {
298		case YPOP_CHANGE:
299		case YPOP_DELETE:
300			err = ERR_KEY;
301			break;
302		case YPOP_INSERT:
303		case YPOP_STORE:
304			err = 0;
305			fprintf(wf, "%s %s\n", key, data);
306			break;
307		}
308	}
309	fclose(wf);
310	fclose(rf);
311	if (err == 0) {
312		if (rename(tmpname, filename) < 0) {
313			err = ERR_DBASE;
314			goto cleanup;
315		}
316	} else {
317		if (unlink(tmpname) < 0) {
318			err = ERR_DBASE;
319			goto cleanup;
320		}
321	}
322cleanup:
323	free(tmpname);
324	return (err);
325}
326
327static int
328match(char *line, char *name)
329{
330	int len;
331
332	len = strlen(name);
333	return (strncmp(line, name, len) == 0 &&
334		(line[len] == ' ' || line[len] == '\t'));
335}
336#endif /* !YP */
337