1 /* $OpenBSD: procs.c,v 1.3 2017/01/21 08:33:51 krw 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 <errno.h> 37 #include <netdb.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <syslog.h> 42 #include <signal.h> 43 #include <unistd.h> 44 45 #include <rpc/rpc.h> 46 47 #include "statd.h" 48 49 /* sm_stat_1 --------------------------------------------------------------- */ 50 /* 51 * Purpose: RPC call to enquire if a host can be monitored 52 * Returns: TRUE for any hostname that can be looked up to give 53 * an address. 54 */ 55 struct sm_stat_res * 56 sm_stat_1_svc(sm_name *arg, struct svc_req *req) 57 { 58 static sm_stat_res res; 59 60 NO_ALARM; 61 if (debug) 62 syslog(LOG_DEBUG, "stat called for host %s", arg->mon_name); 63 64 if (gethostbyname(arg->mon_name)) 65 res.res_stat = stat_succ; 66 else { 67 syslog(LOG_ERR, "invalid hostname to sm_stat: %s", 68 arg->mon_name); 69 res.res_stat = stat_fail; 70 } 71 72 res.state = status_info.ourState; 73 ALARM; 74 return (&res); 75 } 76 77 /* sm_mon_1 ---------------------------------------------------------------- */ 78 /* 79 * Purpose: RPC procedure to establish a monitor request 80 * Returns: Success, unless lack of resources prevents 81 * the necessary structures from being set up 82 * to record the request, or if the hostname is not 83 * valid (as judged by gethostbyname()) 84 */ 85 struct sm_stat_res * 86 sm_mon_1_svc(mon *arg, struct svc_req *req) 87 { 88 static sm_stat_res res; 89 HostInfo *hp, h; 90 MonList *lp; 91 92 NO_ALARM; 93 if (debug) { 94 syslog(LOG_DEBUG, "monitor request for host %s", 95 arg->mon_id.mon_name); 96 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d", 97 arg->mon_id.my_id.my_name, arg->mon_id.my_id.my_prog, 98 arg->mon_id.my_id.my_vers, arg->mon_id.my_id.my_proc); 99 } 100 res.res_stat = stat_fail; /* Assume fail until set otherwise */ 101 res.state = status_info.ourState; 102 103 /* 104 * Find existing host entry, or create one if not found. If 105 * find_host() fails, it will have logged the error already. 106 */ 107 if (!gethostbyname(arg->mon_id.mon_name)) { 108 syslog(LOG_ERR, "Invalid hostname to sm_mon: %s", 109 arg->mon_id.mon_name); 110 return &res; 111 } 112 113 if ((hp = find_host(arg->mon_id.mon_name, &h)) == NULL) 114 memset(hp = &h, 0, sizeof(h)); 115 116 lp = malloc(sizeof(MonList)); 117 if (!lp) 118 syslog(LOG_ERR, "Out of memory"); 119 else { 120 strncpy(lp->notifyHost, arg->mon_id.my_id.my_name, 121 SM_MAXSTRLEN); 122 lp->notifyProg = arg->mon_id.my_id.my_prog; 123 lp->notifyVers = arg->mon_id.my_id.my_vers; 124 lp->notifyProc = arg->mon_id.my_id.my_proc; 125 memcpy(lp->notifyData, arg->priv, 126 sizeof(lp->notifyData)); 127 128 lp->next = hp->monList; 129 hp->monList = lp; 130 change_host(arg->mon_id.mon_name, hp); 131 sync_file(); 132 res.res_stat = stat_succ; /* Report success */ 133 } 134 ALARM; 135 return (&res); 136 } 137 138 /* do_unmon ---------------------------------------------------------------- */ 139 /* 140 * Purpose: Remove a monitor request from a host 141 * Returns: TRUE if found, FALSE if not found. 142 * Notes: Common code from sm_unmon_1_svc and sm_unmon_all_1_svc 143 * In the unlikely event of more than one identical monitor 144 * request, all are removed. 145 */ 146 int 147 do_unmon(char *name, HostInfo *hp, void *ptr) 148 { 149 my_id *idp = ptr; 150 MonList *lp, *next; 151 MonList *last = NULL; 152 int result = FALSE; 153 154 lp = hp->monList; 155 while (lp) { 156 if (!strncasecmp(idp->my_name, lp->notifyHost, SM_MAXSTRLEN) 157 && (idp->my_prog == lp->notifyProg) 158 && (idp->my_proc == lp->notifyProc) 159 && (idp->my_vers == lp->notifyVers)) { 160 /* found one. Unhook from chain and free. */ 161 next = lp->next; 162 if (last) 163 last->next = next; 164 else 165 hp->monList = next; 166 free(lp); 167 lp = next; 168 result = TRUE; 169 } else { 170 last = lp; 171 lp = lp->next; 172 } 173 } 174 return (result); 175 } 176 177 /* sm_unmon_1 -------------------------------------------------------------- */ 178 /* 179 * Purpose: RPC procedure to release a monitor request. 180 * Returns: Local machine's status number 181 * Notes: The supplied mon_id should match the value passed in an 182 * earlier call to sm_mon_1 183 */ 184 struct sm_stat * 185 sm_unmon_1_svc(mon_id *arg, struct svc_req *req) 186 { 187 static sm_stat res; 188 HostInfo *hp, h; 189 190 NO_ALARM; 191 if (debug) { 192 syslog(LOG_DEBUG, "un-monitor request for host %s", 193 arg->mon_name); 194 syslog(LOG_DEBUG, "recall host: %s prog: %d ver: %d proc: %d", 195 arg->my_id.my_name, arg->my_id.my_prog, 196 arg->my_id.my_vers, arg->my_id.my_proc); 197 } 198 if ((hp = find_host(arg->mon_name, &h)) != NULL) { 199 if (do_unmon(arg->mon_name, hp, &arg->my_id)) { 200 change_host(arg->mon_name, hp); 201 sync_file(); 202 } else 203 syslog(LOG_ERR, 204 "unmon request from %s, no matching monitor", 205 arg->my_id.my_name); 206 } else 207 syslog(LOG_ERR, "unmon request from %s for unknown host %s", 208 arg->my_id.my_name, arg->mon_name); 209 210 res.state = status_info.ourState; 211 ALARM; 212 213 return (&res); 214 } 215 216 /* sm_unmon_all_1 ---------------------------------------------------------- */ 217 /* 218 * Purpose: RPC procedure to release monitor requests. 219 * Returns: Local machine's status number 220 * Notes: Releases all monitor requests (if any) from the specified 221 * host and program number. 222 */ 223 struct sm_stat * 224 sm_unmon_all_1_svc(my_id *arg, struct svc_req *req) 225 { 226 static sm_stat res; 227 228 NO_ALARM; 229 if (debug) { 230 syslog(LOG_DEBUG, 231 "unmon_all for host: %s prog: %d ver: %d proc: %d", 232 arg->my_name, arg->my_prog, arg->my_vers, arg->my_proc); 233 } 234 235 unmon_hosts(); 236 sync_file(); 237 238 res.state = status_info.ourState; 239 ALARM; 240 241 return (&res); 242 } 243 244 /* sm_simu_crash_1 --------------------------------------------------------- */ 245 /* 246 * Purpose: RPC procedure to simulate a crash 247 * Returns: Nothing 248 * Notes: Standardised mechanism for debug purposes 249 * The specification says that we should drop all of our 250 * status information (apart from the list of monitored hosts 251 * on disc). However, this would confuse the rpc.lockd 252 * which would be unaware that all of its monitor requests 253 * had been silently junked. Hence we in fact retain all 254 * current requests and simply increment the status counter 255 * and inform all hosts on the monitor list. 256 */ 257 void * 258 sm_simu_crash_1_svc(void *v, struct svc_req *req) 259 { 260 static char dummy; 261 262 NO_ALARM; 263 if (debug) 264 syslog(LOG_DEBUG, "simu_crash called!!"); 265 266 reset_database(); 267 ALARM; 268 notify_handler(0); 269 270 return (&dummy); 271 } 272 273 /* sm_notify_1 ------------------------------------------------------------- */ 274 /* 275 * Purpose: RPC procedure notifying local statd of the crash of another 276 * Returns: Nothing 277 * Notes: There is danger of deadlock, since it is quite likely that 278 * the client procedure that we call will in turn call us 279 * to remove or adjust the monitor request. 280 * We therefore fork() a process to do the notifications. 281 * Note that the main HostInfo structure is in a mmap() 282 * region and so will be shared with the child, but the 283 * monList pointed to by the HostInfo is in normal memory. 284 * Hence if we read the monList before forking, we are 285 * protected from the parent servicing other requests 286 * that modify the list. 287 */ 288 void * 289 sm_notify_1_svc(stat_chge *arg, struct svc_req *req) 290 { 291 struct timeval timeout = {20, 0}; /* 20 secs timeout */ 292 CLIENT *cli; 293 static char dummy; 294 status tx_arg; /* arg sent to callback procedure */ 295 MonList *lp; 296 HostInfo *hp, h; 297 pid_t pid; 298 299 if (debug) 300 syslog(LOG_DEBUG, "notify from host %s, new state %d", 301 arg->mon_name, arg->state); 302 303 hp = find_host(arg->mon_name, &h); 304 if (!hp) { 305 /* Never heard of this host - why is it notifying us? */ 306 syslog(LOG_DEBUG, "Unsolicited notification from host %s", 307 arg->mon_name); 308 return (&dummy); 309 } 310 lp = hp->monList; 311 if (!lp) /* We know this host, but have no outstanding requests. */ 312 return (&dummy); 313 314 sync_file(); 315 pid = fork(); 316 if (pid == -1) { 317 syslog(LOG_ERR, "Unable to fork notify process - %s", 318 strerror(errno)); 319 return (FALSE); 320 } 321 if (pid) 322 return (&dummy); /* Parent returns */ 323 324 while (lp) { 325 tx_arg.mon_name = arg->mon_name; 326 tx_arg.state = arg->state; 327 memcpy(tx_arg.priv, lp->notifyData, sizeof(tx_arg.priv)); 328 cli = clnt_create(lp->notifyHost, lp->notifyProg, 329 lp->notifyVers, "udp"); 330 if (!cli) 331 syslog(LOG_ERR, "Failed to contact host %s%s", 332 lp->notifyHost, clnt_spcreateerror("")); 333 else { 334 if (clnt_call(cli, lp->notifyProc, xdr_status, &tx_arg, 335 xdr_void, &dummy, timeout) != RPC_SUCCESS) 336 syslog(LOG_ERR, 337 "Failed to call rpc.statd client at host %s", 338 lp->notifyHost); 339 clnt_destroy(cli); 340 } 341 lp = lp->next; 342 } 343 344 exit(0); /* Child quits */ 345 } 346