xref: /freebsd/usr.sbin/rpc.ypupdated/update.c (revision e0c4386e)
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 /*
32  * Copyright (C) 1986, 1989, Sun Microsystems, Inc.
33  */
34 
35 /*
36  * Administrative tool to add a new user to the publickey database
37  */
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41 #include <rpc/rpc.h>
42 #include <rpc/key_prot.h>
43 #ifdef YP
44 #include <rpcsvc/yp_prot.h>
45 #include <rpcsvc/ypclnt.h>
46 #include <sys/wait.h>
47 #include <netdb.h>
48 #endif	/* YP */
49 #include <pwd.h>
50 #include <string.h>
51 #include <sys/resource.h>
52 #include "ypupdated_extern.h"
53 
54 #ifdef YP
55 #define	MAXMAPNAMELEN 256
56 #else
57 #define	YPOP_CHANGE 1			/* change, do not add */
58 #define	YPOP_INSERT 2			/* add, do not change */
59 #define	YPOP_DELETE 3			/* delete this entry */
60 #define	YPOP_STORE  4			/* add, or change */
61 #endif
62 
63 #ifdef YP
64 static char SHELL[] = "/bin/sh";
65 static char YPDBPATH[]="/var/yp";	/* This is defined but not used! */
66 static char PKMAP[] = "publickey.byname";
67 static char UPDATEFILE[] = "updaters";
68 static char PKFILE[] = "/etc/publickey";
69 #endif	/* YP */
70 
71 #ifdef YP
72 static int _openchild(char *, FILE **, FILE **);
73 
74 /*
75  * Determine if requester is allowed to update the given map,
76  * and update it if so. Returns the yp status, which is zero
77  * if there is no access violation.
78  */
79 int
80 mapupdate(char *requester, char *mapname, u_int op, u_int keylen, char *key,
81     u_int datalen, char *data)
82 {
83 	char updater[MAXMAPNAMELEN + 40];
84 	FILE *childargs;
85 	FILE *childrslt;
86 #ifdef WEXITSTATUS
87 	int status;
88 #else
89 	union wait status;
90 #endif
91 	pid_t pid;
92 	u_int yperrno;
93 
94 
95 #ifdef DEBUG
96 	printf("%s %s\n", key, data);
97 #endif
98 	(void)sprintf(updater, "make -s -f %s/%s %s", YPDBPATH, /* !!! */
99 					UPDATEFILE, mapname);
100 	pid = _openchild(updater, &childargs, &childrslt);
101 	if (pid < 0) {
102 		return (YPERR_YPERR);
103 	}
104 
105 	/*
106 	 * Write to child
107 	 */
108 	(void)fprintf(childargs, "%s\n", requester);
109 	(void)fprintf(childargs, "%u\n", op);
110 	(void)fprintf(childargs, "%u\n", keylen);
111 	(void)fwrite(key, (int)keylen, 1, childargs);
112 	(void)fprintf(childargs, "\n");
113 	(void)fprintf(childargs, "%u\n", datalen);
114 	(void)fwrite(data, (int)datalen, 1, childargs);
115 	(void)fprintf(childargs, "\n");
116 	(void)fclose(childargs);
117 
118 	/*
119 	 * Read from child
120 	 */
121 	(void)fscanf(childrslt, "%d", &yperrno);
122 	(void)fclose(childrslt);
123 
124 	(void)wait(&status);
125 #ifdef WEXITSTATUS
126 	if (WEXITSTATUS(status) != 0)
127 #else
128 	if (status.w_retcode != 0)
129 #endif
130 		return (YPERR_YPERR);
131 	return (yperrno);
132 }
133 
134 /*
135  * returns pid, or -1 for failure
136  */
137 static int
138 _openchild(char *command, FILE **fto, FILE **ffrom)
139 {
140 	int i;
141 	pid_t pid;
142 	int pdto[2];
143 	int pdfrom[2];
144 	char *com;
145 	struct rlimit rl;
146 
147 	if (pipe(pdto) < 0) {
148 		goto error1;
149 	}
150 	if (pipe(pdfrom) < 0) {
151 		goto error2;
152 	}
153 	switch (pid = fork()) {
154 	case -1:
155 		goto error3;
156 
157 	case 0:
158 		/*
159 		 * child: read from pdto[0], write into pdfrom[1]
160 		 */
161 		(void)close(0);
162 		(void)dup(pdto[0]);
163 		(void)close(1);
164 		(void)dup(pdfrom[1]);
165 		getrlimit(RLIMIT_NOFILE, &rl);
166 		for (i = rl.rlim_max - 1; i >= 3; i--) {
167 			(void) close(i);
168 		}
169 		com = malloc((unsigned) strlen(command) + 6);
170 		if (com == NULL) {
171 			_exit(~0);
172 		}
173 		(void)sprintf(com, "exec %s", command);
174 		execl(SHELL, basename(SHELL), "-c", com, (char *)NULL);
175 		_exit(~0);
176 
177 	default:
178 		/*
179 		 * parent: write into pdto[1], read from pdfrom[0]
180 		 */
181 		*fto = fdopen(pdto[1], "w");
182 		(void)close(pdto[0]);
183 		*ffrom = fdopen(pdfrom[0], "r");
184 		(void)close(pdfrom[1]);
185 		break;
186 	}
187 	return (pid);
188 
189 	/*
190 	 * error cleanup and return
191 	 */
192 error3:
193 	(void)close(pdfrom[0]);
194 	(void)close(pdfrom[1]);
195 error2:
196 	(void)close(pdto[0]);
197 	(void)close(pdto[1]);
198 error1:
199 	return (-1);
200 }
201 
202 static char *
203 basename(char *path)
204 {
205 	char *p;
206 
207 	p = strrchr(path, '/');
208 	if (p == NULL) {
209 		return (path);
210 	} else {
211 		return (p + 1);
212 	}
213 }
214 
215 #else /* YP */
216 
217 static int match(char *, char *);
218 
219 /*
220  * Determine if requester is allowed to update the given map,
221  * and update it if so. Returns the status, which is zero
222  * if there is no access violation. This function updates
223  * the local file and then shuts up.
224  */
225 int
226 localupdate(char *name, char *filename, u_int op, u_int keylen __unused,
227     char *key, u_int datalen __unused, char *data)
228 {
229 	char line[256];
230 	FILE *rf;
231 	FILE *wf;
232 	char *tmpname;
233 	int err;
234 
235 	/*
236 	 * Check permission
237 	 */
238 	if (strcmp(name, key) != 0) {
239 		return (ERR_ACCESS);
240 	}
241 	if (strcmp(name, "nobody") == 0) {
242 		/*
243 		 * Can't change "nobody"s key.
244 		 */
245 		return (ERR_ACCESS);
246 	}
247 
248 	/*
249 	 * Open files
250 	 */
251 	tmpname = malloc(strlen(filename) + 4);
252 	if (tmpname == NULL) {
253 		return (ERR_MALLOC);
254 	}
255 	sprintf(tmpname, "%s.tmp", filename);
256 	rf = fopen(filename, "r");
257 	if (rf == NULL) {
258 		err = ERR_READ;
259 		goto cleanup;
260 	}
261 	wf = fopen(tmpname, "w");
262 	if (wf == NULL) {
263 		fclose(rf);
264 		err = ERR_WRITE;
265 		goto cleanup;
266 	}
267 	err = -1;
268 	while (fgets(line, sizeof (line), rf)) {
269 		if (err < 0 && match(line, name)) {
270 			switch (op) {
271 			case YPOP_INSERT:
272 				err = ERR_KEY;
273 				break;
274 			case YPOP_STORE:
275 			case YPOP_CHANGE:
276 				fprintf(wf, "%s %s\n", key, data);
277 				err = 0;
278 				break;
279 			case YPOP_DELETE:
280 				/* do nothing */
281 				err = 0;
282 				break;
283 			}
284 		} else {
285 			fputs(line, wf);
286 		}
287 	}
288 	if (err < 0) {
289 		switch (op) {
290 		case YPOP_CHANGE:
291 		case YPOP_DELETE:
292 			err = ERR_KEY;
293 			break;
294 		case YPOP_INSERT:
295 		case YPOP_STORE:
296 			err = 0;
297 			fprintf(wf, "%s %s\n", key, data);
298 			break;
299 		}
300 	}
301 	fclose(wf);
302 	fclose(rf);
303 	if (err == 0) {
304 		if (rename(tmpname, filename) < 0) {
305 			err = ERR_DBASE;
306 			goto cleanup;
307 		}
308 	} else {
309 		if (unlink(tmpname) < 0) {
310 			err = ERR_DBASE;
311 			goto cleanup;
312 		}
313 	}
314 cleanup:
315 	free(tmpname);
316 	return (err);
317 }
318 
319 static int
320 match(char *line, char *name)
321 {
322 	int len;
323 
324 	len = strlen(name);
325 	return (strncmp(line, name, len) == 0 &&
326 		(line[len] == ' ' || line[len] == '\t'));
327 }
328 #endif /* !YP */
329