1 /* $NetBSD: stat_proc.c,v 1.9 2018/01/23 21:06:26 sevan Exp $ */
2
3 /*
4 * Copyright (c) 1995
5 * A.R. Gordon (andrew.gordon@net-tel.co.uk). All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed for the FreeBSD project
18 * 4. Neither the name of the author nor the names of any co-contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY ANDREW GORDON AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 */
35
36 #include <sys/cdefs.h>
37 #ifndef lint
38 __RCSID("$NetBSD: stat_proc.c,v 1.9 2018/01/23 21:06:26 sevan Exp $");
39 #endif
40
41 #include <errno.h>
42 #include <netdb.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <syslog.h>
47 #include <signal.h>
48 #include <unistd.h>
49
50 #include <rpc/rpc.h>
51
52 #include "statd.h"
53
54 /* sm_stat_1 --------------------------------------------------------------- */
55 /*
56 * Purpose: RPC call to enquire if a host can be monitored
57 * Returns: TRUE for any hostname that can be looked up to give
58 * an address.
59 */
60 struct sm_stat_res *
sm_stat_1_svc(sm_name * arg,struct svc_req * req)61 sm_stat_1_svc(sm_name *arg, struct svc_req *req)
62 {
63 static sm_stat_res smres;
64 struct addrinfo *ai;
65
66 NO_ALARM;
67 if (debug)
68 syslog(LOG_DEBUG, "stat called for host %s", arg->mon_name);
69
70 if (getaddrinfo(arg->mon_name, NULL, NULL, &ai) == 0) {
71 smres.res_stat = stat_succ;
72 freeaddrinfo(ai);
73 } else {
74 syslog(LOG_ERR, "invalid hostname to sm_stat: %s",
75 arg->mon_name);
76 smres.res_stat = stat_fail;
77 }
78
79 smres.state = status_info.ourState;
80 ALARM;
81 return (&smres);
82 }
83
84 /* sm_mon_1 ---------------------------------------------------------------- */
85 /*
86 * Purpose: RPC procedure to establish a monitor request
87 * Returns: Success, unless lack of resources prevents
88 * the necessary structures from being set up
89 * to record the request, or if the hostname is not
90 * valid (as judged by gethostbyname())
91 */
92 struct sm_stat_res *
sm_mon_1_svc(mon * arg,struct svc_req * req)93 sm_mon_1_svc(mon *arg, struct svc_req *req)
94 {
95 static sm_stat_res smres;
96 struct addrinfo *ai;
97 HostInfo *hp, h;
98 MonList *lp;
99
100 NO_ALARM;
101 if (debug) {
102 syslog(LOG_DEBUG, "monitor request for host %s",
103 arg->mon_id.mon_name);
104 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d",
105 arg->mon_id.my_id.my_name, arg->mon_id.my_id.my_prog,
106 arg->mon_id.my_id.my_vers, arg->mon_id.my_id.my_proc);
107 }
108 smres.res_stat = stat_fail; /* Assume fail until set otherwise */
109 smres.state = status_info.ourState;
110
111 /*
112 * Find existing host entry, or create one if not found. If
113 * find_host() fails, it will have logged the error already.
114 */
115 if (getaddrinfo(arg->mon_id.mon_name, NULL, NULL, &ai) != 0) {
116 syslog(LOG_ERR, "Invalid hostname to sm_mon: %s",
117 arg->mon_id.mon_name);
118 return &smres;
119 }
120
121 freeaddrinfo(ai);
122
123 if ((hp = find_host(arg->mon_id.mon_name, &h)) == NULL)
124 memset(hp = &h, 0, sizeof(h));
125
126 lp = (MonList *)malloc(sizeof(MonList));
127 if (!lp)
128 syslog(LOG_ERR, "Out of memory");
129 else {
130 strncpy(lp->notifyHost, arg->mon_id.my_id.my_name,
131 SM_MAXSTRLEN);
132 lp->notifyProg = arg->mon_id.my_id.my_prog;
133 lp->notifyVers = arg->mon_id.my_id.my_vers;
134 lp->notifyProc = arg->mon_id.my_id.my_proc;
135 memcpy(lp->notifyData, arg->priv,
136 sizeof(lp->notifyData));
137
138 lp->next = hp->monList;
139 hp->monList = lp;
140 change_host(arg->mon_id.mon_name, hp);
141 sync_file();
142 smres.res_stat = stat_succ; /* Report success */
143 }
144 ALARM;
145 return (&smres);
146 }
147
148 /* do_unmon ---------------------------------------------------------------- */
149 /*
150 * Purpose: Remove a monitor request from a host
151 * Returns: TRUE if found, FALSE if not found.
152 * Notes: Common code from sm_unmon_1_svc and sm_unmon_all_1_svc
153 * In the unlikely event of more than one identical monitor
154 * request, all are removed.
155 */
156 int
do_unmon(char * name,HostInfo * hp,void * ptr)157 do_unmon(char *name, HostInfo *hp, void *ptr)
158 {
159 my_id *idp = ptr;
160 MonList *lp, *next;
161 MonList *last = NULL;
162 int result = FALSE;
163
164 lp = hp->monList;
165 while (lp) {
166 if (!strncasecmp(idp->my_name, lp->notifyHost, SM_MAXSTRLEN)
167 && (idp->my_prog == lp->notifyProg)
168 && (idp->my_proc == lp->notifyProc)
169 && (idp->my_vers == lp->notifyVers)) {
170 /* found one. Unhook from chain and free. */
171 next = lp->next;
172 if (last)
173 last->next = next;
174 else
175 hp->monList = next;
176 free(lp);
177 lp = next;
178 result = TRUE;
179 } else {
180 last = lp;
181 lp = lp->next;
182 }
183 }
184 return (result);
185 }
186
187 /* sm_unmon_1 -------------------------------------------------------------- */
188 /*
189 * Purpose: RPC procedure to release a monitor request.
190 * Returns: Local machine's status number
191 * Notes: The supplied mon_id should match the value passed in an
192 * earlier call to sm_mon_1
193 */
194 struct sm_stat *
sm_unmon_1_svc(mon_id * arg,struct svc_req * req)195 sm_unmon_1_svc(mon_id *arg, struct svc_req *req)
196 {
197 static sm_stat smres;
198 HostInfo *hp, h;
199
200 NO_ALARM;
201 if (debug) {
202 syslog(LOG_DEBUG, "un-monitor request for host %s",
203 arg->mon_name);
204 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d",
205 arg->my_id.my_name, arg->my_id.my_prog,
206 arg->my_id.my_vers, arg->my_id.my_proc);
207 }
208 if ((hp = find_host(arg->mon_name, &h)) != NULL) {
209 if (do_unmon(arg->mon_name, hp, &arg->my_id)) {
210 change_host(arg->mon_name, hp);
211 sync_file();
212 }
213 else
214 syslog(LOG_ERR,
215 "unmon request from %s, no matching monitor",
216 arg->my_id.my_name);
217 } else
218 syslog(LOG_ERR, "unmon request from %s for unknown host %s",
219 arg->my_id.my_name, arg->mon_name);
220
221 smres.state = status_info.ourState;
222 ALARM;
223
224 return (&smres);
225 }
226
227 /* sm_unmon_all_1 ---------------------------------------------------------- */
228 /*
229 * Purpose: RPC procedure to release monitor requests.
230 * Returns: Local machine's status number
231 * Notes: Releases all monitor requests (if any) from the specified
232 * host and program number.
233 */
234 struct sm_stat *
sm_unmon_all_1_svc(my_id * arg,struct svc_req * req)235 sm_unmon_all_1_svc(my_id *arg, struct svc_req *req)
236 {
237 static sm_stat smres;
238
239 NO_ALARM;
240 if (debug) {
241 syslog(LOG_DEBUG,
242 "unmon_all for host: %s prog: %d ver: %d proc: %d",
243 arg->my_name, arg->my_prog, arg->my_vers, arg->my_proc);
244 }
245
246 unmon_hosts();
247 sync_file();
248
249 smres.state = status_info.ourState;
250 ALARM;
251
252 return (&smres);
253 }
254
255 /* sm_simu_crash_1 --------------------------------------------------------- */
256 /*
257 * Purpose: RPC procedure to simulate a crash
258 * Returns: Nothing
259 * Notes: Standardised mechanism for debug purposes
260 * The specification says that we should drop all of our
261 * status information (apart from the list of monitored hosts
262 * on disc). However, this would confuse the rpc.lockd
263 * which would be unaware that all of its monitor requests
264 * had been silently junked. Hence we in fact retain all
265 * current requests and simply increment the status counter
266 * and inform all hosts on the monitor list.
267 */
268 void *
sm_simu_crash_1_svc(void * v,struct svc_req * req)269 sm_simu_crash_1_svc(void *v, struct svc_req *req)
270 {
271 static char dummy;
272
273 NO_ALARM;
274 if (debug)
275 syslog(LOG_DEBUG, "simu_crash called!!");
276
277 reset_database();
278 ALARM;
279 notify_handler(0);
280
281 return (&dummy);
282 }
283
284 /* sm_notify_1 ------------------------------------------------------------- */
285 /*
286 * Purpose: RPC procedure notifying local statd of the crash of another
287 * Returns: Nothing
288 * Notes: There is danger of deadlock, since it is quite likely that
289 * the client procedure that we call will in turn call us
290 * to remove or adjust the monitor request.
291 * We therefore fork() a process to do the notifications.
292 * Note that the main HostInfo structure is in a mmap()
293 * region and so will be shared with the child, but the
294 * monList pointed to by the HostInfo is in normal memory.
295 * Hence if we read the monList before forking, we are
296 * protected from the parent servicing other requests
297 * that modify the list.
298 */
299 void *
sm_notify_1_svc(stat_chge * arg,struct svc_req * req)300 sm_notify_1_svc(stat_chge *arg, struct svc_req *req)
301 {
302 struct timeval timeout = {20, 0}; /* 20 secs timeout */
303 CLIENT *cli;
304 static char dummy;
305 status tx_arg; /* arg sent to callback procedure */
306 MonList *lp;
307 HostInfo *hp, h;
308 pid_t pid;
309
310 if (debug)
311 syslog(LOG_DEBUG, "notify from host %s, new state %d",
312 arg->mon_name, arg->state);
313
314 hp = find_host(arg->mon_name, &h);
315 if (!hp) {
316 /* Never heard of this host - why is it notifying us? */
317 syslog(LOG_DEBUG, "Unsolicited notification from host %s",
318 arg->mon_name);
319 return (&dummy);
320 }
321 lp = hp->monList;
322 if (!lp) /* We know this host, but have no outstanding requests. */
323 return (&dummy);
324
325 sync_file();
326 pid = fork();
327 if (pid == -1) {
328 syslog(LOG_ERR, "Unable to fork notify process - %s",
329 strerror(errno));
330 return (FALSE);
331 }
332 if (pid)
333 return (&dummy); /* Parent returns */
334
335 while (lp) {
336 tx_arg.mon_name = arg->mon_name;
337 tx_arg.state = arg->state;
338 memcpy(tx_arg.priv, lp->notifyData, sizeof(tx_arg.priv));
339 cli = clnt_create(lp->notifyHost, lp->notifyProg,
340 lp->notifyVers, "udp");
341 if (!cli)
342 syslog(LOG_ERR, "Failed to contact host %s%s",
343 lp->notifyHost, clnt_spcreateerror(""));
344 else {
345 if (clnt_call(cli, lp->notifyProc, xdr_status, &tx_arg,
346 xdr_void, &dummy, timeout) != RPC_SUCCESS)
347 syslog(LOG_ERR,
348 "Failed to call rpc.statd client at host %s",
349 lp->notifyHost);
350 clnt_destroy(cli);
351 }
352 lp = lp->next;
353 }
354
355 exit(0); /* Child quits */
356 }
357