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-rw-r--r--bin/named/os.c932
1 files changed, 932 insertions, 0 deletions
diff --git a/bin/named/os.c b/bin/named/os.c
new file mode 100644
index 0000000..7af4729
--- /dev/null
+++ b/bin/named/os.c
@@ -0,0 +1,932 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+#include <stdarg.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/types.h> /* dev_t FreeBSD 2.1 */
+#ifdef HAVE_UNAME
+#include <sys/utsname.h>
+#endif /* ifdef HAVE_UNAME */
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <pwd.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syslog.h>
+#ifdef HAVE_TZSET
+#include <time.h>
+#endif /* ifdef HAVE_TZSET */
+#include <unistd.h>
+
+#include <isc/buffer.h>
+#include <isc/file.h>
+#include <isc/print.h>
+#include <isc/resource.h>
+#include <isc/result.h>
+#include <isc/strerr.h>
+#include <isc/string.h>
+#include <isc/util.h>
+
+#include <named/globals.h>
+#include <named/main.h>
+#include <named/os.h>
+#ifdef HAVE_LIBSCF
+#include <named/smf_globals.h>
+#endif /* ifdef HAVE_LIBSCF */
+
+static char *pidfile = NULL;
+static char *lockfile = NULL;
+static int devnullfd = -1;
+static int singletonfd = -1;
+
+#ifndef ISC_FACILITY
+#define ISC_FACILITY LOG_DAEMON
+#endif /* ifndef ISC_FACILITY */
+
+static struct passwd *runas_pw = NULL;
+static bool done_setuid = false;
+static int dfd[2] = { -1, -1 };
+
+#ifdef HAVE_SYS_CAPABILITY_H
+
+static bool non_root = false;
+static bool non_root_caps = false;
+
+#include <sys/capability.h>
+#include <sys/prctl.h>
+
+static void
+linux_setcaps(cap_t caps) {
+ char strbuf[ISC_STRERRORSIZE];
+
+ if ((getuid() != 0 && !non_root_caps) || non_root) {
+ return;
+ }
+ if (cap_set_proc(caps) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("cap_set_proc() failed: %s:"
+ " please ensure that the capset kernel"
+ " module is loaded. see insmod(8)",
+ strbuf);
+ }
+}
+
+#define SET_CAP(flag) \
+ do { \
+ cap_flag_value_t curval; \
+ capval = (flag); \
+ err = cap_get_flag(curcaps, capval, CAP_PERMITTED, &curval); \
+ if (err != -1 && curval) { \
+ err = cap_set_flag(caps, CAP_EFFECTIVE, 1, &capval, \
+ CAP_SET); \
+ if (err == -1) { \
+ strerror_r(errno, strbuf, sizeof(strbuf)); \
+ named_main_earlyfatal("cap_set_proc failed: " \
+ "%s", \
+ strbuf); \
+ } \
+ \
+ err = cap_set_flag(caps, CAP_PERMITTED, 1, &capval, \
+ CAP_SET); \
+ if (err == -1) { \
+ strerror_r(errno, strbuf, sizeof(strbuf)); \
+ named_main_earlyfatal("cap_set_proc failed: " \
+ "%s", \
+ strbuf); \
+ } \
+ } \
+ } while (0)
+#define INIT_CAP \
+ do { \
+ caps = cap_init(); \
+ if (caps == NULL) { \
+ strerror_r(errno, strbuf, sizeof(strbuf)); \
+ named_main_earlyfatal("cap_init failed: %s", strbuf); \
+ } \
+ curcaps = cap_get_proc(); \
+ if (curcaps == NULL) { \
+ strerror_r(errno, strbuf, sizeof(strbuf)); \
+ named_main_earlyfatal("cap_get_proc failed: %s", \
+ strbuf); \
+ } \
+ } while (0)
+#define FREE_CAP \
+ { \
+ cap_free(caps); \
+ cap_free(curcaps); \
+ } \
+ while (0)
+
+static void
+linux_initialprivs(void) {
+ cap_t caps;
+ cap_t curcaps;
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+
+ /*%
+ * We don't need most privileges, so we drop them right away.
+ * Later on linux_minprivs() will be called, which will drop our
+ * capabilities to the minimum needed to run the server.
+ */
+ INIT_CAP;
+
+ /*
+ * We need to be able to bind() to privileged ports, notably port 53!
+ */
+ SET_CAP(CAP_NET_BIND_SERVICE);
+
+ /*
+ * We need chroot() initially too.
+ */
+ SET_CAP(CAP_SYS_CHROOT);
+
+ /*
+ * We need setuid() as the kernel supports keeping capabilities after
+ * setuid().
+ */
+ SET_CAP(CAP_SETUID);
+
+ /*
+ * Since we call initgroups, we need this.
+ */
+ SET_CAP(CAP_SETGID);
+
+ /*
+ * Without this, we run into problems reading a configuration file
+ * owned by a non-root user and non-world-readable on startup.
+ */
+ SET_CAP(CAP_DAC_READ_SEARCH);
+
+ /*
+ * XXX We might want to add CAP_SYS_RESOURCE, though it's not
+ * clear it would work right given the way linuxthreads work.
+ * XXXDCL But since we need to be able to set the maximum number
+ * of files, the stack size, data size, and core dump size to
+ * support named.conf options, this is now being added to test.
+ */
+ SET_CAP(CAP_SYS_RESOURCE);
+
+ /*
+ * We need to be able to set the ownership of the containing
+ * directory of the pid file when we create it.
+ */
+ SET_CAP(CAP_CHOWN);
+
+ linux_setcaps(caps);
+
+ FREE_CAP;
+}
+
+static void
+linux_minprivs(void) {
+ cap_t caps;
+ cap_t curcaps;
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+
+ INIT_CAP;
+ /*%
+ * Drop all privileges except the ability to bind() to privileged
+ * ports.
+ *
+ * It's important that we drop CAP_SYS_CHROOT. If we didn't, it
+ * chroot() could be used to escape from the chrooted area.
+ */
+
+ SET_CAP(CAP_NET_BIND_SERVICE);
+
+ /*
+ * XXX We might want to add CAP_SYS_RESOURCE, though it's not
+ * clear it would work right given the way linuxthreads work.
+ * XXXDCL But since we need to be able to set the maximum number
+ * of files, the stack size, data size, and core dump size to
+ * support named.conf options, this is now being added to test.
+ */
+ SET_CAP(CAP_SYS_RESOURCE);
+
+ linux_setcaps(caps);
+
+ FREE_CAP;
+}
+
+static void
+linux_keepcaps(void) {
+ char strbuf[ISC_STRERRORSIZE];
+ /*%
+ * Ask the kernel to allow us to keep our capabilities after we
+ * setuid().
+ */
+
+ if (prctl(PR_SET_KEEPCAPS, 1, 0, 0, 0) < 0) {
+ if (errno != EINVAL) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("prctl() failed: %s", strbuf);
+ }
+ } else {
+ non_root_caps = true;
+ if (getuid() != 0) {
+ non_root = true;
+ }
+ }
+}
+
+#endif /* HAVE_SYS_CAPABILITY_H */
+
+static void
+setup_syslog(const char *progname) {
+ int options;
+
+ options = LOG_PID;
+#ifdef LOG_NDELAY
+ options |= LOG_NDELAY;
+#endif /* ifdef LOG_NDELAY */
+ openlog(isc_file_basename(progname), options, ISC_FACILITY);
+}
+
+void
+named_os_init(const char *progname) {
+ setup_syslog(progname);
+#ifdef HAVE_SYS_CAPABILITY_H
+ linux_initialprivs();
+#endif /* ifdef HAVE_SYS_CAPABILITY_H */
+#ifdef SIGXFSZ
+ signal(SIGXFSZ, SIG_IGN);
+#endif /* ifdef SIGXFSZ */
+}
+
+void
+named_os_daemonize(void) {
+ pid_t pid;
+ char strbuf[ISC_STRERRORSIZE];
+
+ if (pipe(dfd) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("pipe(): %s", strbuf);
+ }
+
+ pid = fork();
+ if (pid == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("fork(): %s", strbuf);
+ }
+ if (pid != 0) {
+ int n;
+ /*
+ * Wait for the child to finish loading for the first time.
+ * This would be so much simpler if fork() worked once we
+ * were multi-threaded.
+ */
+ (void)close(dfd[1]);
+ do {
+ char buf;
+ n = read(dfd[0], &buf, 1);
+ if (n == 1) {
+ _exit(0);
+ }
+ } while (n == -1 && errno == EINTR);
+ _exit(1);
+ }
+ (void)close(dfd[0]);
+
+ /*
+ * We're the child.
+ */
+
+ if (setsid() == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("setsid(): %s", strbuf);
+ }
+
+ /*
+ * Try to set stdin, stdout, and stderr to /dev/null, but press
+ * on even if it fails.
+ *
+ * XXXMLG The close() calls here are unneeded on all but NetBSD, but
+ * are harmless to include everywhere. dup2() is supposed to close
+ * the FD if it is in use, but unproven-pthreads-0.16 is broken
+ * and will end up closing the wrong FD. This will be fixed eventually,
+ * and these calls will be removed.
+ */
+ if (devnullfd != -1) {
+ if (devnullfd != STDIN_FILENO) {
+ (void)close(STDIN_FILENO);
+ (void)dup2(devnullfd, STDIN_FILENO);
+ }
+ if (devnullfd != STDOUT_FILENO) {
+ (void)close(STDOUT_FILENO);
+ (void)dup2(devnullfd, STDOUT_FILENO);
+ }
+ if (devnullfd != STDERR_FILENO && !named_g_keepstderr) {
+ (void)close(STDERR_FILENO);
+ (void)dup2(devnullfd, STDERR_FILENO);
+ }
+ }
+}
+
+void
+named_os_started(void) {
+ char buf = 0;
+
+ /*
+ * Signal to the parent that we started successfully.
+ */
+ if (dfd[0] != -1 && dfd[1] != -1) {
+ if (write(dfd[1], &buf, 1) != 1) {
+ named_main_earlyfatal("unable to signal parent that we "
+ "otherwise started "
+ "successfully.");
+ }
+ close(dfd[1]);
+ dfd[0] = dfd[1] = -1;
+ }
+}
+
+void
+named_os_opendevnull(void) {
+ devnullfd = open("/dev/null", O_RDWR, 0);
+}
+
+void
+named_os_closedevnull(void) {
+ if (devnullfd != STDIN_FILENO && devnullfd != STDOUT_FILENO &&
+ devnullfd != STDERR_FILENO)
+ {
+ close(devnullfd);
+ devnullfd = -1;
+ }
+}
+
+static bool
+all_digits(const char *s) {
+ if (*s == '\0') {
+ return (false);
+ }
+ while (*s != '\0') {
+ if (!isdigit((unsigned char)(*s))) {
+ return (false);
+ }
+ s++;
+ }
+ return (true);
+}
+
+void
+named_os_chroot(const char *root) {
+ char strbuf[ISC_STRERRORSIZE];
+#ifdef HAVE_LIBSCF
+ named_smf_chroot = 0;
+#endif /* ifdef HAVE_LIBSCF */
+ if (root != NULL) {
+#ifdef HAVE_CHROOT
+ if (chroot(root) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("chroot(): %s", strbuf);
+ }
+#else /* ifdef HAVE_CHROOT */
+ named_main_earlyfatal("chroot(): disabled");
+#endif /* ifdef HAVE_CHROOT */
+ if (chdir("/") < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("chdir(/): %s", strbuf);
+ }
+#ifdef HAVE_LIBSCF
+ /* Set named_smf_chroot flag on successful chroot. */
+ named_smf_chroot = 1;
+#endif /* ifdef HAVE_LIBSCF */
+ }
+}
+
+void
+named_os_inituserinfo(const char *username) {
+ if (username == NULL) {
+ return;
+ }
+
+ if (all_digits(username)) {
+ runas_pw = getpwuid((uid_t)atoi(username));
+ } else {
+ runas_pw = getpwnam(username);
+ }
+ endpwent();
+
+ if (runas_pw == NULL) {
+ named_main_earlyfatal("user '%s' unknown", username);
+ }
+
+ if (getuid() == 0) {
+ char strbuf[ISC_STRERRORSIZE];
+ if (initgroups(runas_pw->pw_name, runas_pw->pw_gid) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("initgroups(): %s", strbuf);
+ }
+ }
+}
+
+void
+named_os_changeuser(void) {
+ char strbuf[ISC_STRERRORSIZE];
+ if (runas_pw == NULL || done_setuid) {
+ return;
+ }
+
+ done_setuid = true;
+
+ if (setgid(runas_pw->pw_gid) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("setgid(): %s", strbuf);
+ }
+
+ if (setuid(runas_pw->pw_uid) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("setuid(): %s", strbuf);
+ }
+
+#if defined(HAVE_SYS_CAPABILITY_H)
+ /*
+ * Restore the ability of named to drop core after the setuid()
+ * call has disabled it.
+ */
+ if (prctl(PR_SET_DUMPABLE, 1, 0, 0, 0) < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("prctl(PR_SET_DUMPABLE) failed: %s",
+ strbuf);
+ }
+
+ linux_minprivs();
+#endif /* if defined(HAVE_SYS_CAPABILITY_H) */
+}
+
+uid_t
+ns_os_uid(void) {
+ if (runas_pw == NULL) {
+ return (0);
+ }
+ return (runas_pw->pw_uid);
+}
+
+void
+named_os_adjustnofile(void) {
+#if defined(__linux__) || defined(__sun)
+ isc_result_t result;
+ isc_resourcevalue_t newvalue;
+
+ /*
+ * Linux: max number of open files specified by one thread doesn't seem
+ * to apply to other threads on Linux.
+ * Sun: restriction needs to be removed sooner when hundreds of CPUs
+ * are available.
+ */
+ newvalue = ISC_RESOURCE_UNLIMITED;
+
+ result = isc_resource_setlimit(isc_resource_openfiles, newvalue);
+ if (result != ISC_R_SUCCESS) {
+ named_main_earlywarning("couldn't adjust limit on open files");
+ }
+#endif /* if defined(__linux__) || defined(__sun) */
+}
+
+void
+named_os_minprivs(void) {
+#if defined(HAVE_SYS_CAPABILITY_H)
+ linux_keepcaps();
+ named_os_changeuser();
+ linux_minprivs();
+#endif /* if defined(HAVE_SYS_CAPABILITY_H) */
+}
+
+static int
+safe_open(const char *filename, mode_t mode, bool append) {
+ int fd;
+ struct stat sb;
+
+ if (stat(filename, &sb) == -1) {
+ if (errno != ENOENT) {
+ return (-1);
+ }
+ } else if ((sb.st_mode & S_IFREG) == 0) {
+ errno = EOPNOTSUPP;
+ return (-1);
+ }
+
+ if (append) {
+ fd = open(filename, O_WRONLY | O_CREAT | O_APPEND, mode);
+ } else {
+ if (unlink(filename) < 0 && errno != ENOENT) {
+ return (-1);
+ }
+ fd = open(filename, O_WRONLY | O_CREAT | O_EXCL, mode);
+ }
+ return (fd);
+}
+
+static void
+cleanup_pidfile(void) {
+ int n;
+ if (pidfile != NULL) {
+ n = unlink(pidfile);
+ if (n == -1 && errno != ENOENT) {
+ named_main_earlywarning("unlink '%s': failed", pidfile);
+ }
+ free(pidfile);
+ }
+ pidfile = NULL;
+}
+
+static void
+cleanup_lockfile(void) {
+ if (singletonfd != -1) {
+ close(singletonfd);
+ singletonfd = -1;
+ }
+
+ if (lockfile != NULL) {
+ int n = unlink(lockfile);
+ if (n == -1 && errno != ENOENT) {
+ named_main_earlywarning("unlink '%s': failed",
+ lockfile);
+ }
+ free(lockfile);
+ lockfile = NULL;
+ }
+}
+
+/*
+ * Ensure that a directory exists.
+ * NOTE: This function overwrites the '/' characters in 'filename' with
+ * nulls. The caller should copy the filename to a fresh buffer first.
+ */
+static int
+mkdirpath(char *filename, void (*report)(const char *, ...)) {
+ char *slash = strrchr(filename, '/');
+ char strbuf[ISC_STRERRORSIZE];
+ unsigned int mode;
+
+ if (slash != NULL && slash != filename) {
+ struct stat sb;
+ *slash = '\0';
+
+ if (stat(filename, &sb) == -1) {
+ if (errno != ENOENT) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ (*report)("couldn't stat '%s': %s", filename,
+ strbuf);
+ goto error;
+ }
+ if (mkdirpath(filename, report) == -1) {
+ goto error;
+ }
+ /*
+ * Handle "//", "/./" and "/../" in path.
+ */
+ if (!strcmp(slash + 1, "") || !strcmp(slash + 1, ".") ||
+ !strcmp(slash + 1, ".."))
+ {
+ *slash = '/';
+ return (0);
+ }
+ mode = S_IRUSR | S_IWUSR | S_IXUSR; /* u=rwx */
+ mode |= S_IRGRP | S_IXGRP; /* g=rx */
+ mode |= S_IROTH | S_IXOTH; /* o=rx */
+ if (mkdir(filename, mode) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ (*report)("couldn't mkdir '%s': %s", filename,
+ strbuf);
+ goto error;
+ }
+ if (runas_pw != NULL &&
+ chown(filename, runas_pw->pw_uid,
+ runas_pw->pw_gid) == -1)
+ {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ (*report)("couldn't chown '%s': %s", filename,
+ strbuf);
+ }
+ }
+ *slash = '/';
+ }
+ return (0);
+
+error:
+ *slash = '/';
+ return (-1);
+}
+
+#if !HAVE_SYS_CAPABILITY_H
+static void
+setperms(uid_t uid, gid_t gid) {
+#if defined(HAVE_SETEGID) || defined(HAVE_SETRESGID)
+ char strbuf[ISC_STRERRORSIZE];
+#endif /* if defined(HAVE_SETEGID) || defined(HAVE_SETRESGID) */
+#if !defined(HAVE_SETEGID) && defined(HAVE_SETRESGID)
+ gid_t oldgid, tmpg;
+#endif /* if !defined(HAVE_SETEGID) && defined(HAVE_SETRESGID) */
+#if !defined(HAVE_SETEUID) && defined(HAVE_SETRESUID)
+ uid_t olduid, tmpu;
+#endif /* if !defined(HAVE_SETEUID) && defined(HAVE_SETRESUID) */
+#if defined(HAVE_SETEGID)
+ if (getegid() != gid && setegid(gid) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("unable to set effective "
+ "gid to %ld: %s",
+ (long)gid, strbuf);
+ }
+#elif defined(HAVE_SETRESGID)
+ if (getresgid(&tmpg, &oldgid, &tmpg) == -1 || oldgid != gid) {
+ if (setresgid(-1, gid, -1) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("unable to set effective "
+ "gid to %d: %s",
+ gid, strbuf);
+ }
+ }
+#endif /* if defined(HAVE_SETEGID) */
+
+#if defined(HAVE_SETEUID)
+ if (geteuid() != uid && seteuid(uid) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("unable to set effective "
+ "uid to %ld: %s",
+ (long)uid, strbuf);
+ }
+#elif defined(HAVE_SETRESUID)
+ if (getresuid(&tmpu, &olduid, &tmpu) == -1 || olduid != uid) {
+ if (setresuid(-1, uid, -1) == -1) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("unable to set effective "
+ "uid to %d: %s",
+ uid, strbuf);
+ }
+ }
+#endif /* if defined(HAVE_SETEUID) */
+}
+#endif /* !HAVE_SYS_CAPABILITY_H */
+
+FILE *
+named_os_openfile(const char *filename, mode_t mode, bool switch_user) {
+ char strbuf[ISC_STRERRORSIZE], *f;
+ FILE *fp;
+ int fd;
+
+ /*
+ * Make the containing directory if it doesn't exist.
+ */
+ f = strdup(filename);
+ if (f == NULL) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("couldn't strdup() '%s': %s", filename,
+ strbuf);
+ return (NULL);
+ }
+ if (mkdirpath(f, named_main_earlywarning) == -1) {
+ free(f);
+ return (NULL);
+ }
+ free(f);
+
+ if (switch_user && runas_pw != NULL) {
+ uid_t olduid = getuid();
+ gid_t oldgid = getgid();
+#if HAVE_SYS_CAPABILITY_H
+ REQUIRE(olduid == runas_pw->pw_uid);
+ REQUIRE(oldgid == runas_pw->pw_gid);
+#else /* HAVE_SYS_CAPABILITY_H */
+ /* Set UID/GID to the one we'll be running with eventually */
+ setperms(runas_pw->pw_uid, runas_pw->pw_gid);
+#endif
+ fd = safe_open(filename, mode, false);
+
+#if !HAVE_SYS_CAPABILITY_H
+ /* Restore UID/GID to previous uid/gid */
+ setperms(olduid, oldgid);
+#endif
+
+ if (fd == -1) {
+ fd = safe_open(filename, mode, false);
+ if (fd != -1) {
+ named_main_earlywarning("Required root "
+ "permissions to open "
+ "'%s'.",
+ filename);
+ } else {
+ named_main_earlywarning("Could not open "
+ "'%s'.",
+ filename);
+ }
+ named_main_earlywarning("Please check file and "
+ "directory permissions "
+ "or reconfigure the filename.");
+ }
+ } else {
+ fd = safe_open(filename, mode, false);
+ }
+
+ if (fd < 0) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("could not open file '%s': %s",
+ filename, strbuf);
+ return (NULL);
+ }
+
+ fp = fdopen(fd, "w");
+ if (fp == NULL) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlywarning("could not fdopen() file '%s': %s",
+ filename, strbuf);
+ }
+
+ return (fp);
+}
+
+void
+named_os_writepidfile(const char *filename, bool first_time) {
+ FILE *fh;
+ pid_t pid;
+ char strbuf[ISC_STRERRORSIZE];
+ void (*report)(const char *, ...);
+
+ /*
+ * The caller must ensure any required synchronization.
+ */
+
+ report = first_time ? named_main_earlyfatal : named_main_earlywarning;
+
+ cleanup_pidfile();
+
+ if (filename == NULL) {
+ return;
+ }
+
+ pidfile = strdup(filename);
+ if (pidfile == NULL) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ (*report)("couldn't strdup() '%s': %s", filename, strbuf);
+ return;
+ }
+
+ fh = named_os_openfile(filename, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH,
+ first_time);
+ if (fh == NULL) {
+ cleanup_pidfile();
+ return;
+ }
+ pid = getpid();
+ if (fprintf(fh, "%ld\n", (long)pid) < 0) {
+ (*report)("fprintf() to pid file '%s' failed", filename);
+ (void)fclose(fh);
+ cleanup_pidfile();
+ return;
+ }
+ if (fflush(fh) == EOF) {
+ (*report)("fflush() to pid file '%s' failed", filename);
+ (void)fclose(fh);
+ cleanup_pidfile();
+ return;
+ }
+ (void)fclose(fh);
+}
+
+bool
+named_os_issingleton(const char *filename) {
+ char strbuf[ISC_STRERRORSIZE];
+ struct flock lock;
+
+ if (singletonfd != -1) {
+ return (true);
+ }
+
+ if (strcasecmp(filename, "none") == 0) {
+ return (true);
+ }
+
+ /*
+ * Make the containing directory if it doesn't exist.
+ */
+ lockfile = strdup(filename);
+ if (lockfile == NULL) {
+ strerror_r(errno, strbuf, sizeof(strbuf));
+ named_main_earlyfatal("couldn't allocate memory for '%s': %s",
+ filename, strbuf);
+ } else {
+ int ret = mkdirpath(lockfile, named_main_earlywarning);
+ if (ret == -1) {
+ named_main_earlywarning("couldn't create '%s'",
+ filename);
+ cleanup_lockfile();
+ return (false);
+ }
+ }
+
+ /*
+ * named_os_openfile() uses safeopen() which removes any existing
+ * files. We can't use that here.
+ */
+ singletonfd = open(filename, O_WRONLY | O_CREAT,
+ S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
+ if (singletonfd == -1) {
+ cleanup_lockfile();
+ return (false);
+ }
+
+ memset(&lock, 0, sizeof(lock));
+ lock.l_type = F_WRLCK;
+ lock.l_whence = SEEK_SET;
+ lock.l_start = 0;
+ lock.l_len = 1;
+
+ /* Non-blocking (does not wait for lock) */
+ if (fcntl(singletonfd, F_SETLK, &lock) == -1) {
+ close(singletonfd);
+ singletonfd = -1;
+ return (false);
+ }
+
+ return (true);
+}
+
+void
+named_os_shutdown(void) {
+ closelog();
+ cleanup_pidfile();
+ cleanup_lockfile();
+}
+
+void
+named_os_shutdownmsg(char *command, isc_buffer_t *text) {
+ char *last, *ptr;
+ pid_t pid;
+
+ /* Skip the command name. */
+ if (strtok_r(command, " \t", &last) == NULL) {
+ return;
+ }
+
+ if ((ptr = strtok_r(NULL, " \t", &last)) == NULL) {
+ return;
+ }
+
+ if (strcmp(ptr, "-p") != 0) {
+ return;
+ }
+
+ pid = getpid();
+
+ (void)isc_buffer_printf(text, "pid: %ld", (long)pid);
+}
+
+void
+named_os_tzset(void) {
+#ifdef HAVE_TZSET
+ tzset();
+#endif /* ifdef HAVE_TZSET */
+}
+
+#ifdef HAVE_UNAME
+static char unamebuf[sizeof(struct utsname)];
+#else
+static const char unamebuf[] = { "unknown architecture" };
+#endif
+static const char *unamep = NULL;
+
+static void
+getuname(void) {
+#ifdef HAVE_UNAME
+ struct utsname uts;
+
+ memset(&uts, 0, sizeof(uts));
+ if (uname(&uts) < 0) {
+ snprintf(unamebuf, sizeof(unamebuf), "unknown architecture");
+ return;
+ }
+
+ snprintf(unamebuf, sizeof(unamebuf), "%s %s %s %s", uts.sysname,
+ uts.machine, uts.release, uts.version);
+#endif /* ifdef HAVE_UNAME */
+ unamep = unamebuf;
+}
+
+const char *
+named_os_uname(void) {
+ if (unamep == NULL) {
+ getuname();
+ }
+ return (unamep);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-04 01:04:47 +0000