1 /* $NetBSD: stat_proc.c,v 1.3 1997/10/17 16:12:48 lukem 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 1.3 1997/10/17 16:12:48 lukem 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 <unistd.h> 48 49 #include <rpc/rpc.h> 50 51 #include "statd.h" 52 53 static int do_unmon __P((HostInfo *, my_id *)); 54 55 /* sm_stat_1 --------------------------------------------------------------- */ 56 /* 57 * Purpose: RPC call to enquire if a host can be monitored 58 * Returns: TRUE for any hostname that can be looked up to give 59 * an address. 60 */ 61 struct sm_stat_res * 62 sm_stat_1_svc(arg, req) 63 sm_name *arg; 64 struct svc_req *req; 65 { 66 static sm_stat_res res; 67 68 if (debug) 69 syslog(LOG_DEBUG, "stat called for host %s", arg->mon_name); 70 71 if (gethostbyname(arg->mon_name)) 72 res.res_stat = stat_succ; 73 else { 74 syslog(LOG_ERR, "invalid hostname to sm_stat: %s", 75 arg->mon_name); 76 res.res_stat = stat_fail; 77 } 78 79 res.state = status_info->ourState; 80 return (&res); 81 } 82 83 /* sm_mon_1 ---------------------------------------------------------------- */ 84 /* 85 * Purpose: RPC procedure to establish a monitor request 86 * Returns: Success, unless lack of resources prevents 87 * the necessary structures from being set up 88 * to record the request, or if the hostname is not 89 * valid (as judged by gethostbyname()) 90 */ 91 struct sm_stat_res * 92 sm_mon_1_svc(arg, req) 93 mon *arg; 94 struct svc_req *req; 95 { 96 static sm_stat_res res; 97 HostInfo *hp; 98 MonList *lp; 99 100 if (debug) { 101 syslog(LOG_DEBUG, "monitor request for host %s", 102 arg->mon_id.mon_name); 103 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d", 104 arg->mon_id.my_id.my_name, arg->mon_id.my_id.my_prog, 105 arg->mon_id.my_id.my_vers, arg->mon_id.my_id.my_proc); 106 } 107 res.res_stat = stat_fail; /* Assume fail until set otherwise */ 108 res.state = status_info->ourState; 109 110 /* 111 * Find existing host entry, or create one if not found. If 112 * find_host() fails, it will have logged the error already. 113 */ 114 if (!gethostbyname(arg->mon_id.mon_name)) 115 syslog(LOG_ERR, "Invalid hostname to sm_mon: %s", 116 arg->mon_id.mon_name); 117 else if ((hp = find_host(arg->mon_id.mon_name, TRUE)) != NULL) { 118 lp = (MonList *)malloc(sizeof(MonList)); 119 if (!lp) 120 syslog(LOG_ERR, "Out of memory"); 121 else { 122 strncpy(lp->notifyHost, arg->mon_id.my_id.my_name, 123 SM_MAXSTRLEN); 124 lp->notifyProg = arg->mon_id.my_id.my_prog; 125 lp->notifyVers = arg->mon_id.my_id.my_vers; 126 lp->notifyProc = arg->mon_id.my_id.my_proc; 127 memcpy(lp->notifyData, arg->priv, 128 sizeof(lp->notifyData)); 129 130 lp->next = hp->monList; 131 hp->monList = lp; 132 sync_file(); 133 134 res.res_stat = stat_succ; /* Report success */ 135 } 136 } 137 return (&res); 138 } 139 140 /* do_unmon ---------------------------------------------------------------- */ 141 /* 142 * Purpose: Remove a monitor request from a host 143 * Returns: TRUE if found, FALSE if not found. 144 * Notes: Common code from sm_unmon_1_svc and sm_unmon_all_1_svc 145 * In the unlikely event of more than one identical monitor 146 * request, all are removed. 147 */ 148 static int 149 do_unmon(hp, idp) 150 HostInfo *hp; 151 my_id *idp; 152 { 153 MonList *lp, *next; 154 MonList *last = NULL; 155 int result = FALSE; 156 157 lp = hp->monList; 158 while (lp) { 159 if (!strncasecmp(idp->my_name, lp->notifyHost, SM_MAXSTRLEN) 160 && (idp->my_prog == lp->notifyProg) 161 && (idp->my_proc == lp->notifyProc) 162 && (idp->my_vers == lp->notifyVers)) { 163 /* found one. Unhook from chain and free. */ 164 next = lp->next; 165 if (last) 166 last->next = next; 167 else 168 hp->monList = next; 169 free(lp); 170 lp = next; 171 result = TRUE; 172 } else { 173 last = lp; 174 lp = lp->next; 175 } 176 } 177 return (result); 178 } 179 180 /* sm_unmon_1 -------------------------------------------------------------- */ 181 /* 182 * Purpose: RPC procedure to release a monitor request. 183 * Returns: Local machine's status number 184 * Notes: The supplied mon_id should match the value passed in an 185 * earlier call to sm_mon_1 186 */ 187 struct sm_stat * 188 sm_unmon_1_svc(arg, req) 189 mon_id *arg; 190 struct svc_req *req; 191 { 192 static sm_stat res; 193 HostInfo *hp; 194 195 if (debug) { 196 syslog(LOG_DEBUG, "un-monitor request for host %s", 197 arg->mon_name); 198 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d", 199 arg->my_id.my_name, arg->my_id.my_prog, 200 arg->my_id.my_vers, arg->my_id.my_proc); 201 } 202 if ((hp = find_host(arg->mon_name, FALSE)) != NULL) { 203 if (do_unmon(hp, &arg->my_id)) 204 sync_file(); 205 else 206 syslog(LOG_ERR, 207 "unmon request from %s, no matching monitor", 208 arg->my_id.my_name); 209 } else 210 syslog(LOG_ERR, "unmon request from %s for unknown host %s", 211 arg->my_id.my_name, arg->mon_name); 212 213 res.state = status_info->ourState; 214 215 return (&res); 216 } 217 218 /* sm_unmon_all_1 ---------------------------------------------------------- */ 219 /* 220 * Purpose: RPC procedure to release monitor requests. 221 * Returns: Local machine's status number 222 * Notes: Releases all monitor requests (if any) from the specified 223 * host and program number. 224 */ 225 struct sm_stat * 226 sm_unmon_all_1_svc(arg, req) 227 my_id *arg; 228 struct svc_req *req; 229 { 230 static sm_stat res; 231 HostInfo *hp; 232 int i; 233 234 if (debug) { 235 syslog(LOG_DEBUG, 236 "unmon_all for host: %s prog: %d ver: %d proc: %d", 237 arg->my_name, arg->my_prog, arg->my_vers, arg->my_proc); 238 } 239 240 for (i = status_info->noOfHosts, hp = status_info->hosts; i; i--, hp++) 241 do_unmon(hp, arg); 242 243 sync_file(); 244 245 res.state = status_info->ourState; 246 247 return (&res); 248 } 249 250 /* sm_simu_crash_1 --------------------------------------------------------- */ 251 /* 252 * Purpose: RPC procedure to simulate a crash 253 * Returns: Nothing 254 * Notes: Standardised mechanism for debug purposes 255 * The specification says that we should drop all of our 256 * status information (apart from the list of monitored hosts 257 * on disc). However, this would confuse the rpc.lockd 258 * which would be unaware that all of its monitor requests 259 * had been silently junked. Hence we in fact retain all 260 * current requests and simply increment the status counter 261 * and inform all hosts on the monitor list. 262 */ 263 void * 264 sm_simu_crash_1_svc(v, req) 265 void *v; 266 struct svc_req *req; 267 { 268 static char dummy; 269 int work_to_do; 270 HostInfo *hp; 271 int i; 272 273 work_to_do = 0; 274 if (debug) 275 syslog(LOG_DEBUG, "simu_crash called!!"); 276 277 /* 278 * Simulate crash by setting notify-required flag on all monitored 279 * hosts, and incrementing our status number. notify_hosts() is 280 * then called to fork a process to do the notifications. 281 */ 282 for (i = status_info->noOfHosts, hp = status_info->hosts; i > 0; 283 i--, hp++) { 284 if (hp->monList) { 285 work_to_do = TRUE; 286 hp->notifyReqd = TRUE; 287 } 288 } 289 status_info->ourState += 2; /* always even numbers if not crashed */ 290 291 if (work_to_do) 292 notify_hosts(); 293 294 return (&dummy); 295 } 296 297 /* sm_notify_1 ------------------------------------------------------------- */ 298 /* 299 * Purpose: RPC procedure notifying local statd of the crash of another 300 * Returns: Nothing 301 * Notes: There is danger of deadlock, since it is quite likely that 302 * the client procedure that we call will in turn call us 303 * to remove or adjust the monitor request. 304 * We therefore fork() a process to do the notifications. 305 * Note that the main HostInfo structure is in a mmap() 306 * region and so will be shared with the child, but the 307 * monList pointed to by the HostInfo is in normal memory. 308 * Hence if we read the monList before forking, we are 309 * protected from the parent servicing other requests 310 * that modify the list. 311 */ 312 void * 313 sm_notify_1_svc(arg, req) 314 stat_chge *arg; 315 struct svc_req *req; 316 { 317 struct timeval timeout = {20, 0}; /* 20 secs timeout */ 318 CLIENT *cli; 319 static char dummy; 320 status tx_arg; /* arg sent to callback procedure */ 321 MonList *lp; 322 HostInfo *hp; 323 pid_t pid; 324 325 if (debug) 326 syslog(LOG_DEBUG, "notify from host %s, new state %d", 327 arg->mon_name, arg->state); 328 329 hp = find_host(arg->mon_name, FALSE); 330 if (!hp) { 331 /* Never heard of this host - why is it notifying us? */ 332 syslog(LOG_ERR, "Unsolicited notification from host %s", 333 arg->mon_name); 334 return (FALSE); 335 } 336 lp = hp->monList; 337 if (!lp) /* We know this host, but have no outstanding requests. */ 338 return (FALSE); 339 340 pid = fork(); 341 if (pid == -1) { 342 syslog(LOG_ERR, "Unable to fork notify process - %s", 343 strerror(errno)); 344 return (FALSE); 345 } 346 if (pid) 347 return (&dummy); /* Parent returns */ 348 349 while (lp) { 350 tx_arg.mon_name = arg->mon_name; 351 tx_arg.state = arg->state; 352 memcpy(tx_arg.priv, lp->notifyData, sizeof(tx_arg.priv)); 353 cli = clnt_create(lp->notifyHost, lp->notifyProg, 354 lp->notifyVers, "udp"); 355 if (!cli) 356 syslog(LOG_ERR, "Failed to contact host %s%s", 357 lp->notifyHost, clnt_spcreateerror("")); 358 else { 359 if (clnt_call(cli, lp->notifyProc, xdr_status, &tx_arg, 360 xdr_void, &dummy, timeout) != RPC_SUCCESS) 361 syslog(LOG_ERR, 362 "Failed to call rpc.statd client at host %s", 363 lp->notifyHost); 364 clnt_destroy(cli); 365 } 366 lp = lp->next; 367 } 368 369 exit(0); /* Child quits */ 370 } 371