| File: | src/usr.sbin/snmpd/snmpd.c |
| Warning: | line 198, column 2 Value stored to 'argv' is never read |
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| 1 | /* $OpenBSD: snmpd.c,v 1.46 2021/08/10 06:52:03 martijn Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 2007, 2008, 2012 Reyk Floeter <reyk@openbsd.org> |
| 5 | * |
| 6 | * Permission to use, copy, modify, and distribute this software for any |
| 7 | * purpose with or without fee is hereby granted, provided that the above |
| 8 | * copyright notice and this permission notice appear in all copies. |
| 9 | * |
| 10 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| 11 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 12 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| 13 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 14 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 15 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF |
| 16 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 17 | */ |
| 18 | |
| 19 | #include <sys/types.h> |
| 20 | #include <sys/queue.h> |
| 21 | #include <sys/socket.h> |
| 22 | #include <sys/wait.h> |
| 23 | #include <sys/tree.h> |
| 24 | |
| 25 | #include <net/if.h> |
| 26 | |
| 27 | #include <string.h> |
| 28 | #include <stdio.h> |
| 29 | #include <stdlib.h> |
| 30 | #include <getopt.h> |
| 31 | #include <err.h> |
| 32 | #include <errno(*__errno()).h> |
| 33 | #include <event.h> |
| 34 | #include <signal.h> |
| 35 | #include <syslog.h> |
| 36 | #include <unistd.h> |
| 37 | #include <fcntl.h> |
| 38 | #include <pwd.h> |
| 39 | |
| 40 | #include "snmpd.h" |
| 41 | #include "mib.h" |
| 42 | |
| 43 | __dead__attribute__((__noreturn__)) void usage(void); |
| 44 | |
| 45 | void snmpd_shutdown(struct snmpd *); |
| 46 | void snmpd_sig_handler(int, short, void *); |
| 47 | int snmpd_dispatch_snmpe(int, struct privsep_proc *, struct imsg *); |
| 48 | int check_child(pid_t, const char *); |
| 49 | |
| 50 | struct snmpd *snmpd_env; |
| 51 | |
| 52 | static struct privsep_proc procs[] = { |
| 53 | { "snmpe", PROC_SNMPE, snmpd_dispatch_snmpe, snmpe, snmpe_shutdown }, |
| 54 | }; |
| 55 | |
| 56 | enum privsep_procid privsep_process; |
| 57 | |
| 58 | void |
| 59 | snmpd_sig_handler(int sig, short event, void *arg) |
| 60 | { |
| 61 | struct privsep *ps = arg; |
| 62 | struct snmpd *env = ps->ps_env; |
| 63 | int die = 0, status, fail, id; |
| 64 | pid_t pid; |
| 65 | char *cause; |
| 66 | |
| 67 | switch (sig) { |
| 68 | case SIGTERM15: |
| 69 | case SIGINT2: |
| 70 | die = 1; |
| 71 | /* FALLTHROUGH */ |
| 72 | case SIGCHLD20: |
| 73 | do { |
| 74 | int len; |
| 75 | |
| 76 | pid = waitpid(WAIT_ANY(-1), &status, WNOHANG1); |
| 77 | if (pid <= 0) |
| 78 | continue; |
| 79 | |
| 80 | fail = 0; |
| 81 | if (WIFSIGNALED(status)(((status) & 0177) != 0177 && ((status) & 0177 ) != 0)) { |
| 82 | fail = 1; |
| 83 | len = asprintf(&cause, "terminated; signal %d", |
| 84 | WTERMSIG(status)(((status) & 0177))); |
| 85 | } else if (WIFEXITED(status)(((status) & 0177) == 0)) { |
| 86 | if (WEXITSTATUS(status)(int)(((unsigned)(status) >> 8) & 0xff) != 0) { |
| 87 | fail = 1; |
| 88 | len = asprintf(&cause, |
| 89 | "exited abnormally"); |
| 90 | } else |
| 91 | len = asprintf(&cause, "exited okay"); |
| 92 | } else |
| 93 | fatalx("unexpected cause of SIGCHLD"); |
| 94 | |
| 95 | if (len == -1) |
| 96 | fatal("asprintf"); |
| 97 | |
| 98 | for (id = 0; id < PROC_MAX; id++) { |
| 99 | if (pid == ps->ps_pid[id] && |
| 100 | check_child(ps->ps_pid[id], |
| 101 | ps->ps_title[id])) { |
| 102 | die = 1; |
| 103 | if (fail) |
| 104 | log_warnx("lost child: %s %s", |
| 105 | ps->ps_title[id], cause); |
| 106 | break; |
| 107 | } |
| 108 | } |
| 109 | free(cause); |
| 110 | } while (pid > 0 || (pid == -1 && errno(*__errno()) == EINTR4)); |
| 111 | |
| 112 | if (die) |
| 113 | snmpd_shutdown(env); |
| 114 | break; |
| 115 | case SIGHUP1: |
| 116 | /* reconfigure */ |
| 117 | break; |
| 118 | case SIGUSR130: |
| 119 | /* ignore */ |
| 120 | break; |
| 121 | default: |
| 122 | fatalx("unexpected signal"); |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | __dead__attribute__((__noreturn__)) void |
| 127 | usage(void) |
| 128 | { |
| 129 | extern char *__progname; |
| 130 | |
| 131 | fprintf(stderr(&__sF[2]), "usage: %s [-dNnv] [-D macro=value] " |
| 132 | "[-f file]\n", __progname); |
| 133 | exit(1); |
| 134 | } |
| 135 | |
| 136 | int |
| 137 | main(int argc, char *argv[]) |
| 138 | { |
| 139 | int c; |
| 140 | struct snmpd *env; |
| 141 | int debug = 0, verbose = 0; |
| 142 | u_int flags = 0; |
| 143 | int noaction = 0; |
| 144 | const char *conffile = CONF_FILE"/etc/snmpd.conf"; |
| 145 | struct privsep *ps; |
| 146 | int proc_id = PROC_PARENT, proc_instance = 0; |
| 147 | int argc0 = argc; |
| 148 | char **argv0 = argv; |
| 149 | const char *errp, *title = NULL((void *)0); |
| 150 | |
| 151 | smi_init(); |
| 152 | |
| 153 | /* log to stderr until daemonized */ |
| 154 | log_init(1, LOG_DAEMON(3<<3)); |
| 155 | |
| 156 | while ((c = getopt(argc, argv, "dD:nNf:I:P:v")) != -1) { |
| 157 | switch (c) { |
| 158 | case 'd': |
| 159 | debug++; |
| 160 | flags |= SNMPD_F_DEBUG0x02; |
| 161 | break; |
| 162 | case 'D': |
| 163 | if (cmdline_symset(optarg) < 0) |
| 164 | log_warnx("could not parse macro definition %s", |
| 165 | optarg); |
| 166 | break; |
| 167 | case 'n': |
| 168 | noaction = 1; |
| 169 | break; |
| 170 | case 'N': |
| 171 | flags |= SNMPD_F_NONAMES0x04; |
| 172 | break; |
| 173 | case 'f': |
| 174 | conffile = optarg; |
| 175 | break; |
| 176 | case 'I': |
| 177 | proc_instance = strtonum(optarg, 0, |
| 178 | PROC_MAX_INSTANCES32, &errp); |
| 179 | if (errp) |
| 180 | fatalx("invalid process instance"); |
| 181 | break; |
| 182 | case 'P': |
| 183 | title = optarg; |
| 184 | proc_id = proc_getid(procs, nitems(procs)(sizeof((procs)) / sizeof((procs)[0])), title); |
| 185 | if (proc_id == PROC_MAX) |
| 186 | fatalx("invalid process name"); |
| 187 | break; |
| 188 | case 'v': |
| 189 | verbose++; |
| 190 | flags |= SNMPD_F_VERBOSE0x01; |
| 191 | break; |
| 192 | default: |
| 193 | usage(); |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | argc -= optind; |
| 198 | argv += optind; |
Value stored to 'argv' is never read | |
| 199 | if (argc > 0) |
| 200 | usage(); |
| 201 | |
| 202 | if ((env = parse_config(conffile, flags)) == NULL((void *)0)) |
| 203 | exit(1); |
| 204 | |
| 205 | ps = &env->sc_ps; |
| 206 | ps->ps_env = env; |
| 207 | snmpd_env = env; |
| 208 | ps->ps_instance = proc_instance; |
| 209 | if (title) |
| 210 | ps->ps_title[proc_id] = title; |
| 211 | |
| 212 | if (noaction) { |
| 213 | fprintf(stderr(&__sF[2]), "configuration ok\n"); |
| 214 | exit(0); |
| 215 | } |
| 216 | |
| 217 | if (geteuid()) |
| 218 | errx(1, "need root privileges"); |
| 219 | |
| 220 | if ((ps->ps_pw = getpwnam(SNMPD_USER"_snmpd")) == NULL((void *)0)) |
| 221 | errx(1, "unknown user %s", SNMPD_USER"_snmpd"); |
| 222 | |
| 223 | log_init(debug, LOG_DAEMON(3<<3)); |
| 224 | log_setverbose(verbose); |
| 225 | |
| 226 | gettimeofday(&env->sc_starttime, NULL((void *)0)); |
| 227 | env->sc_engine_boots = 0; |
| 228 | |
| 229 | pf_init(); |
| 230 | |
| 231 | proc_init(ps, procs, nitems(procs)(sizeof((procs)) / sizeof((procs)[0])), debug, argc0, argv0, proc_id); |
| 232 | if (!debug && daemon(0, 0) == -1) |
| 233 | err(1, "failed to daemonize"); |
| 234 | |
| 235 | log_procinit("parent"); |
| 236 | log_info("startup"); |
| 237 | |
| 238 | event_init(); |
| 239 | |
| 240 | signal_set(&ps->ps_evsigint, SIGINT, snmpd_sig_handler, ps)event_set(&ps->ps_evsigint, 2, 0x08|0x10, snmpd_sig_handler , ps); |
| 241 | signal_set(&ps->ps_evsigterm, SIGTERM, snmpd_sig_handler, ps)event_set(&ps->ps_evsigterm, 15, 0x08|0x10, snmpd_sig_handler , ps); |
| 242 | signal_set(&ps->ps_evsigchld, SIGCHLD, snmpd_sig_handler, ps)event_set(&ps->ps_evsigchld, 20, 0x08|0x10, snmpd_sig_handler , ps); |
| 243 | signal_set(&ps->ps_evsighup, SIGHUP, snmpd_sig_handler, ps)event_set(&ps->ps_evsighup, 1, 0x08|0x10, snmpd_sig_handler , ps); |
| 244 | signal_set(&ps->ps_evsigpipe, SIGPIPE, snmpd_sig_handler, ps)event_set(&ps->ps_evsigpipe, 13, 0x08|0x10, snmpd_sig_handler , ps); |
| 245 | signal_set(&ps->ps_evsigusr1, SIGUSR1, snmpd_sig_handler, ps)event_set(&ps->ps_evsigusr1, 30, 0x08|0x10, snmpd_sig_handler , ps); |
| 246 | |
| 247 | signal_add(&ps->ps_evsigint, NULL)event_add(&ps->ps_evsigint, ((void *)0)); |
| 248 | signal_add(&ps->ps_evsigterm, NULL)event_add(&ps->ps_evsigterm, ((void *)0)); |
| 249 | signal_add(&ps->ps_evsigchld, NULL)event_add(&ps->ps_evsigchld, ((void *)0)); |
| 250 | signal_add(&ps->ps_evsighup, NULL)event_add(&ps->ps_evsighup, ((void *)0)); |
| 251 | signal_add(&ps->ps_evsigpipe, NULL)event_add(&ps->ps_evsigpipe, ((void *)0)); |
| 252 | signal_add(&ps->ps_evsigusr1, NULL)event_add(&ps->ps_evsigusr1, ((void *)0)); |
| 253 | |
| 254 | proc_connect(ps); |
| 255 | |
| 256 | if (pledge("stdio dns sendfd proc exec id", NULL((void *)0)) == -1) |
| 257 | fatal("pledge"); |
| 258 | |
| 259 | event_dispatch(); |
| 260 | |
| 261 | log_debug("%d parent exiting", getpid()); |
| 262 | |
| 263 | return (0); |
| 264 | } |
| 265 | |
| 266 | void |
| 267 | snmpd_shutdown(struct snmpd *env) |
| 268 | { |
| 269 | proc_kill(&env->sc_ps); |
| 270 | |
| 271 | free(env); |
| 272 | |
| 273 | log_info("terminating"); |
| 274 | exit(0); |
| 275 | } |
| 276 | |
| 277 | int |
| 278 | check_child(pid_t pid, const char *pname) |
| 279 | { |
| 280 | int status; |
| 281 | |
| 282 | if (waitpid(pid, &status, WNOHANG1) > 0) { |
| 283 | if (WIFEXITED(status)(((status) & 0177) == 0)) { |
| 284 | log_warnx("check_child: lost child: %s exited", pname); |
| 285 | return (1); |
| 286 | } |
| 287 | if (WIFSIGNALED(status)(((status) & 0177) != 0177 && ((status) & 0177 ) != 0)) { |
| 288 | log_warnx("check_child: lost child: %s terminated; " |
| 289 | "signal %d", pname, WTERMSIG(status)(((status) & 0177))); |
| 290 | return (1); |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | return (0); |
| 295 | } |
| 296 | |
| 297 | int |
| 298 | snmpd_dispatch_snmpe(int fd, struct privsep_proc *p, struct imsg *imsg) |
| 299 | { |
| 300 | switch (imsg->hdr.type) { |
| 301 | case IMSG_TRAP_EXEC: |
| 302 | return (traphandler_priv_recvmsg(p, imsg)); |
| 303 | case IMSG_CTL_RELOAD: |
| 304 | /* XXX notyet */ |
| 305 | default: |
| 306 | break; |
| 307 | } |
| 308 | |
| 309 | return (-1); |
| 310 | } |
| 311 | |
| 312 | int |
| 313 | snmpd_socket_af(struct sockaddr_storage *ss, int type) |
| 314 | { |
| 315 | int fd, serrno; |
| 316 | const int enable = 1; |
| 317 | |
| 318 | fd = socket(ss->ss_family, (type == SOCK_STREAM1 ? |
| 319 | SOCK_STREAM1 | SOCK_NONBLOCK0x4000 : SOCK_DGRAM2) | SOCK_CLOEXEC0x8000, 0); |
| 320 | if (fd == -1) |
| 321 | return -1; |
| 322 | |
| 323 | if (setsockopt(fd, SOL_SOCKET0xffff, SO_REUSEADDR0x0004, &enable, |
| 324 | sizeof(enable)) == -1) { |
| 325 | serrno = errno(*__errno()); |
| 326 | close(fd); |
| 327 | errno(*__errno()) = serrno; |
| 328 | return -1; |
| 329 | } |
| 330 | return fd; |
| 331 | } |
| 332 | |
| 333 | u_long |
| 334 | snmpd_engine_time(void) |
| 335 | { |
| 336 | struct timeval now; |
| 337 | |
| 338 | /* |
| 339 | * snmpEngineBoots should be stored in a non-volatile storage. |
| 340 | * snmpEngineTime is the number of seconds since snmpEngineBoots |
| 341 | * was last incremented. We don't rely on non-volatile storage. |
| 342 | * snmpEngineBoots is set to zero and snmpEngineTime to the system |
| 343 | * clock. Hence, the tuple (snmpEngineBoots, snmpEngineTime) is |
| 344 | * still unique and protects us against replay attacks. It only |
| 345 | * 'expires' a little bit sooner than the RFC3414 method. |
| 346 | */ |
| 347 | gettimeofday(&now, NULL((void *)0)); |
| 348 | return now.tv_sec; |
| 349 | } |