diff options
Diffstat (limited to 'server/src/daemon.cc')
| -rw-r--r-- | server/src/daemon.cc | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/server/src/daemon.cc b/server/src/daemon.cc new file mode 100644 index 0000000..a88fa39 --- /dev/null +++ b/server/src/daemon.cc @@ -0,0 +1,158 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * daemon.cc + * + * Thu Jun 9 10:27:59 CEST 2005 + * Copyright 2005 Bent Bisballe + * deva@aasimon.org + ****************************************************************************/ + +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include "daemon.h" + +#include <sys/stat.h> +#include <unistd.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <errno.h> + +// For getgrent and getgrent +#include <sys/types.h> +#include <grp.h> +#include <pwd.h> + +// For strcmp +#include <string.h> + +/* Resolve a group's name or id into a numeric gid */ +static gid_t get_gid(const char *grp) +{ + char *eptr; + gid_t xid = strtoul(grp, &eptr, 10); + struct group *gr; + errno = 0; /* Per getgrnam(3) and getgrgid(3) manual page */ + if(!*eptr) + gr = getgrgid(xid); + else + gr = getgrnam(grp); + return !gr ? 0 : gr->gr_gid; +} + +/* Resolve a user's name or id into a numeric uid with associated gid */ +static uid_t get_uid(const char *usr, gid_t *gid) +{ + char *eptr; + uid_t xid = strtoul(usr, &eptr, 10); + struct passwd *pw; + errno = 0; /* Per getpwnam(3) and getpwuid(3) manual page */ + if(!*eptr) + pw = getpwuid(xid); + else + pw = getpwnam(usr); + if(!pw) + return 0; + if(!gid) + *gid = pw->pw_gid; + return pw->pw_uid; +} + +Daemon::Daemon() +{} + +Daemon::~Daemon() +{} + +int Daemon::run(const char *user, const char* group, bool detach) +{ + int f; + int fd; + + // Fetch user and group IDs + gid_t gid = 0; + uid_t uid = 0; + if(user && *user) { + uid = get_uid(user, &gid); + if(errno) { + fprintf(stderr, "Could resolve user \"%s\"", user); + perror(""); + } + } + + if(group && *group) { + gid = get_gid(group); + if(errno) { + fprintf(stderr, "Could not resolve group \"%s\"", group); + perror(""); + } + } + + chdir("/"); + umask(0); + + if(detach) { + switch(fork()) { + case -1: // Fork error + perror("Fork in daemon.cc"); + return 1; + + case 0: // Forked child + break; // Break out of switch + + default: // Parent + // exit(0); + return 0; + } + } + + if(gid) { + // Switch to given group + if(setgid(gid) != 0) { + fprintf(stderr, "Failed to change to group \"%s\" (gid: %d), quitting.\n", group, gid); + perror(""); + fprintf(stderr, "Runnning daemon as current group\n"); + } + } + + if(uid) { + // Switch to given user + if(setuid(uid) != 0) { + fprintf(stderr, "Failed to change to user \"%s\" (uid: %d), quitting.\n", user, uid); + perror(""); + fprintf(stderr, "Runnning daemon as current user\n"); + } + } + + // Redirect stdin, stdout and stderr to /dev/null + fd = open("/dev/null", O_NOCTTY | O_RDWR, 0666); + + dup2(0, fd); + dup2(1, fd); + dup2(2, fd); + + close(fd); + + setsid(); + + signal (SIGTERM, SIG_IGN); + signal (SIGHUP, SIG_IGN); + if(detach) signal (SIGINT, SIG_IGN); // Don't disable Ctrl+c when running in foreground. + + return daemon_main(); +} |