Mercurial > routeflapper
annotate src/routeflapper.cpp @ 3:4a81cc2da570
fix hourly randomization for unsynch
| author | Carl Byington <carl@five-ten-sg.com> |
|---|---|
| date | Thu, 22 May 2008 20:39:52 -0700 |
| parents | bb3f804f13a0 |
| children | 180d26aa2a17 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 | |
| 3 Copyright (c) 2007 Carl Byington - 510 Software Group, released under | |
| 4 the GPL version 3 or any later version at your choice available at | |
| 5 http://www.gnu.org/licenses/gpl-3.0.txt | |
| 6 | |
| 7 */ | |
| 8 | |
| 9 | |
| 10 // debug levels: | |
| 11 //14 - show regex matches | |
| 12 // 4 - show route annoucement/withdraw actions | |
| 13 // 3 - show suspicious routes announcements, and hourly totals | |
| 14 // 2 - show files open/close | |
| 15 // 1 - show config files loading | |
| 16 | |
| 17 #include "includes.h" | |
| 18 #include <iostream> | |
| 19 #include <cstdlib> | |
| 20 #include <errno.h> | |
| 21 #include <sysexits.h> | |
| 22 #include <pthread.h> | |
| 23 #include <syslog.h> | |
| 24 #include <sys/wait.h> /* header for waitpid() and various macros */ | |
| 25 #include <signal.h> /* header for signal functions */ | |
| 26 | |
| 27 #ifndef HAVE_DAEMON | |
| 28 #include "daemon.h" | |
| 29 #include "daemon.c" | |
| 30 #endif | |
| 31 | |
| 32 extern "C" { | |
| 33 void sigchld(int sig); | |
| 34 void sigterm(int sig); | |
| 35 } | |
| 36 int debug_syslog = 0; | |
| 37 bool syslog_opened = false; | |
| 38 bool use_syslog = true; // false to printf | |
| 39 bool loader_run = true; // used to stop the config loader thread | |
| 40 CONFIG *config = NULL; // protected by the config_mutex | |
| 41 int generation = 0; // protected by the config_mutex | |
| 42 const int maxlen = 1000; // used for snprintf buffers | |
| 43 | |
| 44 pthread_mutex_t config_mutex; | |
| 45 pthread_mutex_t syslog_mutex; | |
| 46 | |
| 47 | |
| 48 //////////////////////////////////////////////// | |
| 49 // syslog a message | |
| 50 // | |
|
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4a81cc2da570
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51 void my_syslog(char *text) |
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4a81cc2da570
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52 { |
| 0 | 53 if (use_syslog) { |
| 54 pthread_mutex_lock(&syslog_mutex); | |
| 55 if (!syslog_opened) { | |
| 56 openlog("routeflapper", LOG_PID, LOG_AUTHPRIV); | |
| 57 syslog_opened = true; | |
| 58 } | |
| 59 syslog(LOG_NOTICE, "%s", text); | |
| 60 pthread_mutex_unlock(&syslog_mutex); | |
| 61 } | |
| 62 else { | |
| 63 printf("%s\n", text); | |
| 64 } | |
| 65 } | |
| 66 | |
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67 |
| 0 | 68 //////////////////////////////////////////////// |
| 69 // reload the config | |
| 70 // | |
| 71 CONFIG* new_conf(); | |
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72 CONFIG* new_conf() |
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73 { |
| 0 | 74 CONFIG *newc = new CONFIG; |
| 75 pthread_mutex_lock(&config_mutex); | |
| 76 newc->generation = generation++; | |
| 77 pthread_mutex_unlock(&config_mutex); | |
| 78 if (debug_syslog) { | |
| 79 char buf[maxlen]; | |
| 80 snprintf(buf, sizeof(buf), "loading configuration generation %d", newc->generation); | |
| 81 my_syslog(buf); | |
| 82 } | |
| 83 if (load_conf(*newc, "routeflapper.conf")) { | |
| 84 newc->load_time = time(NULL); | |
| 85 return newc; | |
| 86 } | |
| 87 delete newc; | |
| 88 return NULL; | |
| 89 } | |
| 90 | |
| 91 | |
| 92 //////////////////////////////////////////////// | |
| 93 // thread to update hourly statistics | |
| 94 // | |
| 95 void* hourly_update(void *arg); | |
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96 void* hourly_update(void *arg) |
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97 { |
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98 unsigned seed = (unsigned)time(NULL); |
| 0 | 99 while (loader_run) { |
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100 int ran = (rand_r(&seed) % 600) - 300; // random(-5min,+5min) |
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bb3f804f13a0
add random unsynchronization to hourly timer, trust prefix only for same origin AS, ignore self adjacency
Carl Byington <carl@five-ten-sg.com>
parents:
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101 int hour = 3600 - 60 + ran; // 59 minutes +- random up to 5 minutes. |
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bb3f804f13a0
add random unsynchronization to hourly timer, trust prefix only for same origin AS, ignore self adjacency
Carl Byington <carl@five-ten-sg.com>
parents:
0
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102 int period = (hour + 10) / 20; // twenty periods ... |
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4a81cc2da570
fix hourly randomization for unsynch
Carl Byington <carl@five-ten-sg.com>
parents:
2
diff
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103 for (int count = 0; loader_run && (count < 20); count++) { |
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bb3f804f13a0
add random unsynchronization to hourly timer, trust prefix only for same origin AS, ignore self adjacency
Carl Byington <carl@five-ten-sg.com>
parents:
0
diff
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104 sleep(period); |
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bb3f804f13a0
add random unsynchronization to hourly timer, trust prefix only for same origin AS, ignore self adjacency
Carl Byington <carl@five-ten-sg.com>
parents:
0
diff
changeset
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105 } |
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3
4a81cc2da570
fix hourly randomization for unsynch
Carl Byington <carl@five-ten-sg.com>
parents:
2
diff
changeset
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106 if (!loader_run) break; // ... so we only wait about 3 minutes to terminate |
|
4a81cc2da570
fix hourly randomization for unsynch
Carl Byington <carl@five-ten-sg.com>
parents:
2
diff
changeset
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107 routing_hourly_update(); // roughly an hour |
| 0 | 108 } |
| 109 } | |
| 110 | |
| 111 | |
| 112 //////////////////////////////////////////////// | |
| 113 // thread to watch the old config files for changes | |
| 114 // and reload when needed. | |
| 115 // | |
| 116 void* config_loader(void *arg); | |
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4a81cc2da570
fix hourly randomization for unsynch
Carl Byington <carl@five-ten-sg.com>
parents:
2
diff
changeset
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117 void* config_loader(void *arg) |
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4a81cc2da570
fix hourly randomization for unsynch
Carl Byington <carl@five-ten-sg.com>
parents:
2
diff
changeset
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118 { |
| 0 | 119 typedef set<CONFIG *> configp_set; |
| 120 while (loader_run) { | |
| 121 sleep(180); // look for modifications every 3 minutes | |
| 122 if (!loader_run) break; | |
| 123 CONFIG &dc = *config; | |
| 124 time_t then = dc.load_time; | |
| 125 struct stat st; | |
| 126 bool reload = false; | |
| 127 for (string_set::iterator i=dc.config_files.begin(); i!=dc.config_files.end(); i++) { | |
| 128 char *fn = *i; | |
| 129 if (stat(fn, &st)) reload = true; // file disappeared | |
| 130 else if (st.st_mtime > then) reload = true; // file modified | |
| 131 if (reload) break; | |
| 132 } | |
| 133 if (reload) { | |
| 134 CONFIG *newc = new_conf(); | |
| 135 if (newc) { | |
| 136 // replace the global config pointer | |
| 137 pthread_mutex_lock(&config_mutex); | |
| 138 config = newc; | |
| 139 pthread_mutex_unlock(&config_mutex); | |
| 140 } | |
| 141 else { | |
| 142 // failed to load new config | |
| 143 my_syslog("failed to load new configuration"); | |
| 144 system("echo 'failed to load new /etc/routeflapper.conf' | mail -s 'error in /etc/routeflapper.conf' root"); | |
| 145 // update the load time on the current config to prevent complaining every 3 minutes | |
| 146 dc.load_time = time(NULL); | |
| 147 } | |
| 148 } | |
| 149 } | |
| 150 return NULL; | |
| 151 } | |
| 152 | |
| 153 | |
| 154 //////////////////////////////////////////////// | |
| 155 // The signal handler function for child process terminations, | |
| 156 // called when a child terminates. | |
| 157 // | |
| 158 void sigchld(int sig) | |
| 159 { | |
| 160 int status; | |
| 161 /* Wait for any child without blocking */ | |
| 162 while (waitpid(-1, &status, WNOHANG) > 0) { | |
| 163 // ignore child exit status, we only do this to cleanup zombies | |
| 164 } | |
| 165 } | |
| 166 | |
| 167 | |
| 168 //////////////////////////////////////////////// | |
| 169 // The termination signal handler function, called to | |
| 170 // request termination of this process. | |
| 171 // | |
| 172 void sigterm(int sig) | |
| 173 { | |
| 174 loader_run = false; | |
| 175 signal(sig, SIG_DFL); // quit on repeated signals | |
| 176 } | |
| 177 | |
| 178 | |
| 179 void usage(char *prog); | |
| 180 void usage(char *prog) | |
| 181 { | |
| 182 fprintf(stderr, "Usage: %s [-d [level]] [-c]\n", prog); | |
| 183 fprintf(stderr, "-c will load and dump the config to stdout\n"); | |
| 184 fprintf(stderr, "-d will set the syslog message level, currently 0 to 3\n"); | |
| 185 } | |
| 186 | |
| 187 | |
| 188 void worker(); | |
| 189 void worker() | |
| 190 { | |
| 191 CONFIG *c; | |
| 192 pthread_mutex_lock(&config_mutex); | |
| 193 c = config; | |
| 194 c->reference_count++; | |
| 195 pthread_mutex_unlock(&config_mutex); | |
| 196 while (loader_run) { | |
| 197 if (c != config) { | |
| 198 pthread_mutex_lock(&config_mutex); | |
| 199 CONFIG *old = c; old->reference_count--; | |
| 200 c = config; c->reference_count++; | |
| 201 pthread_mutex_unlock(&config_mutex); | |
| 202 if (!old->reference_count) { | |
| 203 if (debug_syslog) { | |
| 204 char buf[maxlen]; | |
| 205 snprintf(buf, sizeof(buf), "freeing memory for old configuration generation %d", old->generation); | |
| 206 my_syslog(buf); | |
| 207 } | |
| 208 delete old; // destructor does all the work | |
| 209 } | |
| 210 } | |
| 211 c->read(); | |
| 212 ::sleep(2); | |
| 213 } | |
| 214 } | |
| 215 | |
| 216 | |
| 217 int main(int argc, char *argv[]) | |
| 218 { | |
| 219 token_init(); | |
| 220 bool check = false; | |
| 221 int c; | |
| 222 const char *args = "d:ch"; | |
| 223 extern char *optarg; | |
| 224 | |
| 225 // Process command line options | |
| 226 while ((c = getopt(argc, argv, args)) != -1) { | |
| 227 switch (c) { | |
| 228 case 'c': | |
| 229 check = true; | |
| 230 break; | |
| 231 | |
| 232 case 'd': | |
| 233 if (optarg == NULL || *optarg == '\0') debug_syslog = 1; | |
| 234 else debug_syslog = atoi(optarg); | |
| 235 break; | |
| 236 | |
| 237 case 'h': | |
| 238 default: | |
| 239 usage(argv[0]); | |
| 240 exit(EX_USAGE); | |
| 241 } | |
| 242 } | |
| 243 | |
| 244 if (check) { | |
| 245 use_syslog = false; | |
| 246 debug_syslog = 10; | |
| 247 config = new_conf(); | |
| 248 if (config) { | |
| 249 config->dump(); | |
| 250 delete config; | |
| 251 clear_strings(); // for valgrind checking | |
| 252 return 0; | |
| 253 } | |
| 254 else { | |
| 255 return 1; // config failed to load | |
| 256 } | |
| 257 } | |
| 258 | |
| 259 // switch to background mode | |
| 260 if (daemon(1,0) < 0) { | |
| 261 fprintf(stderr, "daemon() call failed\n"); | |
| 262 exit(EX_UNAVAILABLE); | |
| 263 } | |
| 264 | |
| 265 // write the pid | |
| 266 const char *pidpath = "/var/run/routeflapper.pid"; | |
| 267 unlink(pidpath); | |
| 268 FILE *f = fopen(pidpath, "w"); | |
| 269 if (f) { | |
| 270 #ifdef linux | |
| 271 // from a comment in the DCC source code: | |
| 272 // Linux threads are broken. Signals given the | |
| 273 // original process are delivered to only the | |
| 274 // thread that happens to have that PID. The | |
| 275 // sendmail libmilter thread that needs to hear | |
| 276 // SIGINT and other signals does not, and that breaks | |
| 277 // scripts that need to stop milters. | |
| 278 // However, signaling the process group works. | |
| 279 fprintf(f, "-%d\n", (u_int)getpgrp()); | |
| 280 #else | |
| 281 fprintf(f, "%d\n", (u_int)getpid()); | |
| 282 #endif | |
| 283 fclose(f); | |
| 284 } | |
| 285 | |
| 286 // setup signal handler for termination signals | |
| 287 signal(SIGHUP, sigterm); | |
| 288 signal(SIGTERM, sigterm); | |
| 289 signal(SIGINT, sigterm); | |
| 290 | |
| 291 // initialize the thread sync objects | |
| 292 pthread_mutex_init(&config_mutex, 0); | |
| 293 pthread_mutex_init(&syslog_mutex, 0); | |
| 294 | |
| 295 // load the initial config | |
| 296 config = new_conf(); | |
| 297 if (!config) { | |
| 298 my_syslog("failed to load initial configuration, quitting"); | |
| 299 exit(1); | |
| 300 } | |
| 301 | |
| 302 // setup sigchld handler to prevent zombies | |
| 303 struct sigaction act; | |
| 304 act.sa_handler = sigchld; // Assign sig_chld as our SIGCHLD handler | |
| 305 sigemptyset(&act.sa_mask); // We don't want to block any other signals in this example | |
| 306 act.sa_flags = SA_NOCLDSTOP; // only want children that have terminated | |
| 307 if (sigaction(SIGCHLD, &act, NULL) < 0) { | |
| 308 my_syslog("failed to setup SIGCHLD handler"); | |
| 309 exit(1); | |
| 310 } | |
| 311 | |
| 312 // only create threads after the fork() in daemon | |
| 313 pthread_t tid; | |
| 314 if (pthread_create(&tid, 0, config_loader, 0)) | |
| 315 my_syslog("failed to create config loader thread"); | |
| 316 if (pthread_detach(tid)) | |
| 317 my_syslog("failed to detach config loader thread"); | |
| 318 if (pthread_create(&tid, 0, hourly_update, 0)) | |
| 319 my_syslog("failed to create hourly update thread"); | |
| 320 if (pthread_detach(tid)) | |
| 321 my_syslog("failed to detach hourly update thread"); | |
| 322 | |
| 323 worker(); | |
| 324 if (config) delete config; // for valgrind checking | |
| 325 clear_strings(); // for valgrind checking | |
| 326 clear_rib(); // for valgrind checking | |
| 327 | |
| 328 return EXIT_SUCCESS; | |
| 329 } |