1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2010 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * netcfgd - network configuration daemon. At present, this daemon implements 29 * the configuration backend for libnwam (via calls to nwam_backend_init() 30 * and nwam_backend_fini()). Initialization of the backend creates a door 31 * that libnwam calls use to read, update and destroy persistent configuration. 32 * 33 * More long-term, netcfgd will be used to manage other sources of configuration 34 * data and the backend functionality currently contained in libnwam will be 35 * generalized. 36 */ 37 38 #include <errno.h> 39 #include <signal.h> 40 #include <stdio.h> 41 #include <stdarg.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <syslog.h> 45 #include <sys/types.h> 46 #include <sys/stat.h> 47 #include <unistd.h> 48 #include <wait.h> 49 #include <libnwam_priv.h> 50 #include <libnwam.h> 51 52 static const char *progname; 53 static boolean_t fg = B_FALSE; 54 55 /* 56 * This function allows you to drop a dtrace probe here and trace 57 * complete strings (not just those containing formatting). It's 58 * important that we actually format the strings so we could trace them 59 * even if we choose not to log them. 60 */ 61 static void 62 log_out(int severity, const char *str) 63 { 64 if (fg) { 65 (void) fprintf(stderr, "%s: %s\n", progname, str); 66 } else { 67 syslog(severity, str); 68 } 69 } 70 71 /* PRINTFLIKE2 */ 72 void 73 nlog(int severity, const char *fmt, ...) 74 { 75 va_list ap; 76 char *vbuf; 77 78 va_start(ap, fmt); 79 if (vasprintf(&vbuf, fmt, ap) != -1) { 80 log_out(severity, vbuf); 81 free(vbuf); 82 } 83 va_end(ap); 84 } 85 86 static void 87 start_logging(void) 88 { 89 if (!fg) 90 openlog(progname, LOG_PID, LOG_DAEMON); 91 92 nlog(LOG_DEBUG, "%s started", progname); 93 } 94 95 static void 96 daemonize(void) 97 { 98 pid_t pid; 99 100 /* 101 * A little bit of magic here. By the first fork+setsid, we 102 * disconnect from our current controlling terminal and become 103 * a session group leader. By forking again without calling 104 * setsid again, we make certain that we are not the session 105 * group leader and can never reacquire a controlling terminal. 106 */ 107 if ((pid = fork()) == -1) { 108 nlog(LOG_ERR, "fork 1 failed"); 109 exit(EXIT_FAILURE); 110 } 111 if (pid != 0) { 112 (void) wait(NULL); 113 nlog(LOG_DEBUG, "child %ld exited, daemonizing", pid); 114 _exit(0); 115 } 116 if (setsid() == (pid_t)-1) { 117 nlog(LOG_ERR, "setsid"); 118 exit(EXIT_FAILURE); 119 } 120 if ((pid = fork()) == -1) { 121 nlog(LOG_ERR, "fork 2 failed"); 122 exit(EXIT_FAILURE); 123 } 124 if (pid != 0) { 125 _exit(0); 126 } 127 (void) chdir("/"); 128 (void) umask(022); 129 } 130 131 /* ARGSUSED */ 132 static void 133 graceful_shutdown(int signo) 134 { 135 nwam_backend_fini(); 136 exit(EXIT_SUCCESS); 137 } 138 139 int 140 main(int argc, char *argv[]) 141 { 142 int c; 143 nwam_error_t err; 144 145 if ((progname = strrchr(argv[0], '/')) == NULL) 146 progname = argv[0]; 147 else 148 progname++; 149 150 while ((c = getopt(argc, argv, "f")) != -1) { 151 switch (c) { 152 case 'f': 153 fg = B_TRUE; 154 break; 155 default: 156 (void) fprintf(stderr, "%s: unrecognized option %c\n", 157 progname, optopt); 158 exit(EXIT_FAILURE); 159 } 160 } 161 start_logging(); 162 163 if (!fg) 164 daemonize(); 165 166 (void) signal(SIGTERM, graceful_shutdown); 167 (void) signal(SIGQUIT, graceful_shutdown); 168 (void) signal(SIGPIPE, SIG_IGN); 169 (void) signal(SIGCHLD, SIG_IGN); 170 (void) atexit(nwam_backend_fini); 171 172 if ((err = nwam_backend_init()) != NWAM_SUCCESS) { 173 nlog(LOG_ERR, 174 "couldn't initialize libnwam backend: %s", 175 nwam_strerror(err)); 176 exit(EXIT_FAILURE); 177 } 178 179 for (;;) 180 (void) pause(); 181 182 /* NOTREACHED */ 183 return (EXIT_SUCCESS); 184 } 185