966 lines
22 KiB
C
966 lines
22 KiB
C
/*
|
|
* Copyright (C) 2004-2011 Internet Systems Consortium, Inc. ("ISC")
|
|
* Copyright (C) 1999-2002 Internet Software Consortium.
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
|
|
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
|
|
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
|
|
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
|
|
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
|
|
* PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
/* $Id: os.c,v 1.104.38.3 2011/03/02 00:04:01 marka Exp $ */
|
|
|
|
/*! \file */
|
|
|
|
#include <config.h>
|
|
#include <stdarg.h>
|
|
|
|
#include <sys/types.h> /* dev_t FreeBSD 2.1 */
|
|
#include <sys/stat.h>
|
|
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <grp.h> /* Required for initgroups() on IRIX. */
|
|
#include <pwd.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <signal.h>
|
|
#include <syslog.h>
|
|
#ifdef HAVE_TZSET
|
|
#include <time.h>
|
|
#endif
|
|
#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/strerror.h>
|
|
#include <isc/string.h>
|
|
|
|
#include <named/main.h>
|
|
#include <named/os.h>
|
|
#ifdef HAVE_LIBSCF
|
|
#include <named/ns_smf_globals.h>
|
|
#endif
|
|
|
|
static char *pidfile = NULL;
|
|
static int devnullfd = -1;
|
|
|
|
#ifndef ISC_FACILITY
|
|
#define ISC_FACILITY LOG_DAEMON
|
|
#endif
|
|
|
|
/*
|
|
* If there's no <linux/capability.h>, we don't care about <sys/prctl.h>
|
|
*/
|
|
#ifndef HAVE_LINUX_CAPABILITY_H
|
|
#undef HAVE_SYS_PRCTL_H
|
|
#endif
|
|
|
|
/*
|
|
* Linux defines:
|
|
* (T) HAVE_LINUXTHREADS
|
|
* (C) HAVE_SYS_CAPABILITY_H (or HAVE_LINUX_CAPABILITY_H)
|
|
* (P) HAVE_SYS_PRCTL_H
|
|
* The possible cases are:
|
|
* none: setuid() normally
|
|
* T: no setuid()
|
|
* C: setuid() normally, drop caps (keep CAP_SETUID)
|
|
* T+C: no setuid(), drop caps (don't keep CAP_SETUID)
|
|
* T+C+P: setuid() early, drop caps (keep CAP_SETUID)
|
|
* C+P: setuid() normally, drop caps (keep CAP_SETUID)
|
|
* P: not possible
|
|
* T+P: not possible
|
|
*
|
|
* if (C)
|
|
* caps = BIND_SERVICE + CHROOT + SETGID
|
|
* if ((T && C && P) || !T)
|
|
* caps += SETUID
|
|
* endif
|
|
* capset(caps)
|
|
* endif
|
|
* if (T && C && P && -u)
|
|
* setuid()
|
|
* else if (T && -u)
|
|
* fail
|
|
* --> start threads
|
|
* if (!T && -u)
|
|
* setuid()
|
|
* if (C && (P || !-u))
|
|
* caps = BIND_SERVICE
|
|
* capset(caps)
|
|
* endif
|
|
*
|
|
* It will be nice when Linux threads work properly with setuid().
|
|
*/
|
|
|
|
#ifdef HAVE_LINUXTHREADS
|
|
static pid_t mainpid = 0;
|
|
#endif
|
|
|
|
static struct passwd *runas_pw = NULL;
|
|
static isc_boolean_t done_setuid = ISC_FALSE;
|
|
static int dfd[2] = { -1, -1 };
|
|
|
|
#ifdef HAVE_LINUX_CAPABILITY_H
|
|
|
|
static isc_boolean_t non_root = ISC_FALSE;
|
|
static isc_boolean_t non_root_caps = ISC_FALSE;
|
|
|
|
#ifdef HAVE_SYS_CAPABILITY_H
|
|
#include <sys/capability.h>
|
|
#else
|
|
/*%
|
|
* We define _LINUX_FS_H to prevent it from being included. We don't need
|
|
* anything from it, and the files it includes cause warnings with 2.2
|
|
* kernels, and compilation failures (due to conflicts between <linux/string.h>
|
|
* and <string.h>) on 2.3 kernels.
|
|
*/
|
|
#define _LINUX_FS_H
|
|
#include <linux/capability.h>
|
|
#include <syscall.h>
|
|
#ifndef SYS_capset
|
|
#ifndef __NR_capset
|
|
#include <asm/unistd.h> /* Slackware 4.0 needs this. */
|
|
#endif /* __NR_capset */
|
|
#define SYS_capset __NR_capset
|
|
#endif /* SYS_capset */
|
|
#endif /* HAVE_SYS_CAPABILITY_H */
|
|
|
|
#ifdef HAVE_SYS_PRCTL_H
|
|
#include <sys/prctl.h> /* Required for prctl(). */
|
|
|
|
/*
|
|
* If the value of PR_SET_KEEPCAPS is not in <sys/prctl.h>, define it
|
|
* here. This allows setuid() to work on systems running a new enough
|
|
* kernel but with /usr/include/linux pointing to "standard" kernel
|
|
* headers.
|
|
*/
|
|
#ifndef PR_SET_KEEPCAPS
|
|
#define PR_SET_KEEPCAPS 8
|
|
#endif
|
|
|
|
#endif /* HAVE_SYS_PRCTL_H */
|
|
|
|
#ifdef HAVE_LIBCAP
|
|
#define SETCAPS_FUNC "cap_set_proc "
|
|
#else
|
|
typedef unsigned int cap_t;
|
|
#define SETCAPS_FUNC "syscall(capset) "
|
|
#endif /* HAVE_LIBCAP */
|
|
|
|
static void
|
|
linux_setcaps(cap_t caps) {
|
|
#ifndef HAVE_LIBCAP
|
|
struct __user_cap_header_struct caphead;
|
|
struct __user_cap_data_struct cap;
|
|
#endif
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
|
|
if ((getuid() != 0 && !non_root_caps) || non_root)
|
|
return;
|
|
#ifndef HAVE_LIBCAP
|
|
memset(&caphead, 0, sizeof(caphead));
|
|
caphead.version = _LINUX_CAPABILITY_VERSION;
|
|
caphead.pid = 0;
|
|
memset(&cap, 0, sizeof(cap));
|
|
cap.effective = caps;
|
|
cap.permitted = caps;
|
|
cap.inheritable = 0;
|
|
#endif
|
|
#ifdef HAVE_LIBCAP
|
|
if (cap_set_proc(caps) < 0) {
|
|
#else
|
|
if (syscall(SYS_capset, &caphead, &cap) < 0) {
|
|
#endif
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal(SETCAPS_FUNC "failed: %s:"
|
|
" please ensure that the capset kernel"
|
|
" module is loaded. see insmod(8)",
|
|
strbuf);
|
|
}
|
|
}
|
|
|
|
#ifdef HAVE_LIBCAP
|
|
#define SET_CAP(flag) \
|
|
do { \
|
|
capval = (flag); \
|
|
cap_flag_value_t curval; \
|
|
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) { \
|
|
isc__strerror(errno, strbuf, sizeof(strbuf)); \
|
|
ns_main_earlyfatal("cap_set_proc failed: %s", strbuf); \
|
|
} \
|
|
\
|
|
err = cap_set_flag(caps, CAP_PERMITTED, 1, &capval, CAP_SET); \
|
|
if (err == -1) { \
|
|
isc__strerror(errno, strbuf, sizeof(strbuf)); \
|
|
ns_main_earlyfatal("cap_set_proc failed: %s", strbuf); \
|
|
} \
|
|
} \
|
|
} while (0)
|
|
#define INIT_CAP \
|
|
do { \
|
|
caps = cap_init(); \
|
|
if (caps == NULL) { \
|
|
isc__strerror(errno, strbuf, sizeof(strbuf)); \
|
|
ns_main_earlyfatal("cap_init failed: %s", strbuf); \
|
|
} \
|
|
curcaps = cap_get_proc(); \
|
|
if (curcaps == NULL) { \
|
|
isc__strerror(errno, strbuf, sizeof(strbuf)); \
|
|
ns_main_earlyfatal("cap_get_proc failed: %s", strbuf); \
|
|
} \
|
|
} while (0)
|
|
#define FREE_CAP \
|
|
{ \
|
|
cap_free(caps); \
|
|
cap_free(curcaps); \
|
|
} while (0)
|
|
#else
|
|
#define SET_CAP(flag) do { caps |= (1 << (flag)); } while (0)
|
|
#define INIT_CAP do { caps = 0; } while (0)
|
|
#endif /* HAVE_LIBCAP */
|
|
|
|
static void
|
|
linux_initialprivs(void) {
|
|
cap_t caps;
|
|
#ifdef HAVE_LIBCAP
|
|
cap_t curcaps;
|
|
cap_value_t capval;
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
int err;
|
|
#endif
|
|
|
|
/*%
|
|
* 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);
|
|
|
|
#if defined(HAVE_SYS_PRCTL_H) || !defined(HAVE_LINUXTHREADS)
|
|
/*
|
|
* We can setuid() only if either the kernel supports keeping
|
|
* capabilities after setuid() (which we don't know until we've
|
|
* tried) or we're not using threads. If either of these is
|
|
* true, we want the setuid capability.
|
|
*/
|
|
SET_CAP(CAP_SETUID);
|
|
#endif
|
|
|
|
/*
|
|
* 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);
|
|
|
|
#ifdef HAVE_LIBCAP
|
|
FREE_CAP;
|
|
#endif
|
|
}
|
|
|
|
static void
|
|
linux_minprivs(void) {
|
|
cap_t caps;
|
|
#ifdef HAVE_LIBCAP
|
|
cap_t curcaps;
|
|
cap_value_t capval;
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
int err;
|
|
#endif
|
|
|
|
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);
|
|
|
|
#ifdef HAVE_LIBCAP
|
|
FREE_CAP;
|
|
#endif
|
|
}
|
|
|
|
#ifdef HAVE_SYS_PRCTL_H
|
|
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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("prctl() failed: %s", strbuf);
|
|
}
|
|
} else {
|
|
non_root_caps = ISC_TRUE;
|
|
if (getuid() != 0)
|
|
non_root = ISC_TRUE;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#endif /* HAVE_LINUX_CAPABILITY_H */
|
|
|
|
|
|
static void
|
|
setup_syslog(const char *progname) {
|
|
int options;
|
|
|
|
options = LOG_PID;
|
|
#ifdef LOG_NDELAY
|
|
options |= LOG_NDELAY;
|
|
#endif
|
|
openlog(isc_file_basename(progname), options, ISC_FACILITY);
|
|
}
|
|
|
|
void
|
|
ns_os_init(const char *progname) {
|
|
setup_syslog(progname);
|
|
#ifdef HAVE_LINUX_CAPABILITY_H
|
|
linux_initialprivs();
|
|
#endif
|
|
#ifdef HAVE_LINUXTHREADS
|
|
mainpid = getpid();
|
|
#endif
|
|
#ifdef SIGXFSZ
|
|
signal(SIGXFSZ, SIG_IGN);
|
|
#endif
|
|
}
|
|
|
|
void
|
|
ns_os_daemonize(void) {
|
|
pid_t pid;
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
|
|
if (pipe(dfd) == -1) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("pipe(): %s", strbuf);
|
|
}
|
|
|
|
pid = fork();
|
|
if (pid == -1) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_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.
|
|
*/
|
|
|
|
#ifdef HAVE_LINUXTHREADS
|
|
mainpid = getpid();
|
|
#endif
|
|
|
|
if (setsid() == -1) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_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) {
|
|
(void)close(STDERR_FILENO);
|
|
(void)dup2(devnullfd, STDERR_FILENO);
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
ns_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)
|
|
ns_main_earlyfatal("unable to signal parent that we "
|
|
"otherwise started successfully.");
|
|
close(dfd[1]);
|
|
dfd[0] = dfd[1] = -1;
|
|
}
|
|
}
|
|
|
|
void
|
|
ns_os_opendevnull(void) {
|
|
devnullfd = open("/dev/null", O_RDWR, 0);
|
|
}
|
|
|
|
void
|
|
ns_os_closedevnull(void) {
|
|
if (devnullfd != STDIN_FILENO &&
|
|
devnullfd != STDOUT_FILENO &&
|
|
devnullfd != STDERR_FILENO) {
|
|
close(devnullfd);
|
|
devnullfd = -1;
|
|
}
|
|
}
|
|
|
|
static isc_boolean_t
|
|
all_digits(const char *s) {
|
|
if (*s == '\0')
|
|
return (ISC_FALSE);
|
|
while (*s != '\0') {
|
|
if (!isdigit((*s)&0xff))
|
|
return (ISC_FALSE);
|
|
s++;
|
|
}
|
|
return (ISC_TRUE);
|
|
}
|
|
|
|
void
|
|
ns_os_chroot(const char *root) {
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
#ifdef HAVE_LIBSCF
|
|
ns_smf_chroot = 0;
|
|
#endif
|
|
if (root != NULL) {
|
|
#ifdef HAVE_CHROOT
|
|
if (chroot(root) < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("chroot(): %s", strbuf);
|
|
}
|
|
#else
|
|
ns_main_earlyfatal("chroot(): disabled");
|
|
#endif
|
|
if (chdir("/") < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("chdir(/): %s", strbuf);
|
|
}
|
|
#ifdef HAVE_LIBSCF
|
|
/* Set ns_smf_chroot flag on successful chroot. */
|
|
ns_smf_chroot = 1;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
void
|
|
ns_os_inituserinfo(const char *username) {
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
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)
|
|
ns_main_earlyfatal("user '%s' unknown", username);
|
|
|
|
if (getuid() == 0) {
|
|
if (initgroups(runas_pw->pw_name, runas_pw->pw_gid) < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("initgroups(): %s", strbuf);
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
void
|
|
ns_os_changeuser(void) {
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
if (runas_pw == NULL || done_setuid)
|
|
return;
|
|
|
|
done_setuid = ISC_TRUE;
|
|
|
|
#ifdef HAVE_LINUXTHREADS
|
|
#ifdef HAVE_LINUX_CAPABILITY_H
|
|
if (!non_root_caps)
|
|
ns_main_earlyfatal("-u with Linux threads not supported: "
|
|
"requires kernel support for "
|
|
"prctl(PR_SET_KEEPCAPS)");
|
|
#else
|
|
ns_main_earlyfatal("-u with Linux threads not supported: "
|
|
"no capabilities support or capabilities "
|
|
"disabled at build time");
|
|
#endif
|
|
#endif
|
|
|
|
if (setgid(runas_pw->pw_gid) < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("setgid(): %s", strbuf);
|
|
}
|
|
|
|
if (setuid(runas_pw->pw_uid) < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlyfatal("setuid(): %s", strbuf);
|
|
}
|
|
|
|
#if defined(HAVE_SYS_PRCTL_H) && defined(PR_SET_DUMPABLE)
|
|
/*
|
|
* 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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("prctl(PR_SET_DUMPABLE) failed: %s",
|
|
strbuf);
|
|
}
|
|
#endif
|
|
#if defined(HAVE_LINUX_CAPABILITY_H) && !defined(HAVE_LINUXTHREADS)
|
|
linux_minprivs();
|
|
#endif
|
|
}
|
|
|
|
void
|
|
ns_os_adjustnofile() {
|
|
#ifdef HAVE_LINUXTHREADS
|
|
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.
|
|
*/
|
|
newvalue = ISC_RESOURCE_UNLIMITED;
|
|
|
|
result = isc_resource_setlimit(isc_resource_openfiles, newvalue);
|
|
if (result != ISC_R_SUCCESS)
|
|
ns_main_earlywarning("couldn't adjust limit on open files");
|
|
#endif
|
|
}
|
|
|
|
void
|
|
ns_os_minprivs(void) {
|
|
#ifdef HAVE_SYS_PRCTL_H
|
|
linux_keepcaps();
|
|
#endif
|
|
|
|
#ifdef HAVE_LINUXTHREADS
|
|
ns_os_changeuser(); /* Call setuid() before threads are started */
|
|
#endif
|
|
|
|
#if defined(HAVE_LINUX_CAPABILITY_H) && defined(HAVE_LINUXTHREADS)
|
|
linux_minprivs();
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
safe_open(const char *filename, mode_t mode, isc_boolean_t 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)
|
|
ns_main_earlywarning("unlink '%s': failed", pidfile);
|
|
free(pidfile);
|
|
}
|
|
pidfile = NULL;
|
|
}
|
|
|
|
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) {
|
|
isc__strerror(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) {
|
|
isc__strerror(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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
(*report)("couldn't chown '%s': %s", filename,
|
|
strbuf);
|
|
}
|
|
}
|
|
*slash = '/';
|
|
}
|
|
return (0);
|
|
|
|
error:
|
|
*slash = '/';
|
|
return (-1);
|
|
}
|
|
|
|
static void
|
|
setperms(uid_t uid, gid_t gid) {
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
#if !defined(HAVE_SETEGID) && defined(HAVE_SETRESGID)
|
|
gid_t oldgid, tmpg;
|
|
#endif
|
|
#if !defined(HAVE_SETEUID) && defined(HAVE_SETRESUID)
|
|
uid_t olduid, tmpu;
|
|
#endif
|
|
#if defined(HAVE_SETEGID)
|
|
if (getegid() != gid && setegid(gid) == -1) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("unable to set effective "
|
|
"gid to %d: %s", gid, strbuf);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(HAVE_SETEUID)
|
|
if (geteuid() != uid && seteuid(uid) == -1) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("unable to set effective "
|
|
"uid to %d: %s", uid, strbuf);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
FILE *
|
|
ns_os_openfile(const char *filename, mode_t mode, isc_boolean_t 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) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("couldn't strdup() '%s': %s",
|
|
filename, strbuf);
|
|
return (NULL);
|
|
}
|
|
if (mkdirpath(f, ns_main_earlywarning) == -1) {
|
|
free(f);
|
|
return (NULL);
|
|
}
|
|
free(f);
|
|
|
|
if (switch_user && runas_pw != NULL) {
|
|
#ifndef HAVE_LINUXTHREADS
|
|
gid_t oldgid = getgid();
|
|
#endif
|
|
/* Set UID/GID to the one we'll be running with eventually */
|
|
setperms(runas_pw->pw_uid, runas_pw->pw_gid);
|
|
|
|
fd = safe_open(filename, mode, ISC_FALSE);
|
|
|
|
#ifndef HAVE_LINUXTHREADS
|
|
/* Restore UID/GID to root */
|
|
setperms(0, oldgid);
|
|
#endif /* HAVE_LINUXTHREADS */
|
|
|
|
if (fd == -1) {
|
|
#ifndef HAVE_LINUXTHREADS
|
|
fd = safe_open(filename, mode, ISC_FALSE);
|
|
if (fd != -1) {
|
|
ns_main_earlywarning("Required root "
|
|
"permissions to open "
|
|
"'%s'.", filename);
|
|
} else {
|
|
ns_main_earlywarning("Could not open "
|
|
"'%s'.", filename);
|
|
}
|
|
ns_main_earlywarning("Please check file and "
|
|
"directory permissions "
|
|
"or reconfigure the filename.");
|
|
#else /* HAVE_LINUXTHREADS */
|
|
ns_main_earlywarning("Could not open "
|
|
"'%s'.", filename);
|
|
ns_main_earlywarning("Please check file and "
|
|
"directory permissions "
|
|
"or reconfigure the filename.");
|
|
#endif /* HAVE_LINUXTHREADS */
|
|
}
|
|
} else {
|
|
fd = safe_open(filename, mode, ISC_FALSE);
|
|
}
|
|
|
|
if (fd < 0) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("could not open file '%s': %s",
|
|
filename, strbuf);
|
|
return (NULL);
|
|
}
|
|
|
|
fp = fdopen(fd, "w");
|
|
if (fp == NULL) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
ns_main_earlywarning("could not fdopen() file '%s': %s",
|
|
filename, strbuf);
|
|
}
|
|
|
|
return (fp);
|
|
}
|
|
|
|
void
|
|
ns_os_writepidfile(const char *filename, isc_boolean_t first_time) {
|
|
FILE *lockfile;
|
|
pid_t pid;
|
|
char strbuf[ISC_STRERRORSIZE];
|
|
void (*report)(const char *, ...);
|
|
|
|
/*
|
|
* The caller must ensure any required synchronization.
|
|
*/
|
|
|
|
report = first_time ? ns_main_earlyfatal : ns_main_earlywarning;
|
|
|
|
cleanup_pidfile();
|
|
|
|
if (filename == NULL)
|
|
return;
|
|
|
|
pidfile = strdup(filename);
|
|
if (pidfile == NULL) {
|
|
isc__strerror(errno, strbuf, sizeof(strbuf));
|
|
(*report)("couldn't strdup() '%s': %s", filename, strbuf);
|
|
return;
|
|
}
|
|
|
|
lockfile = ns_os_openfile(filename, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
|
|
first_time);
|
|
if (lockfile == NULL) {
|
|
cleanup_pidfile();
|
|
return;
|
|
}
|
|
#ifdef HAVE_LINUXTHREADS
|
|
pid = mainpid;
|
|
#else
|
|
pid = getpid();
|
|
#endif
|
|
if (fprintf(lockfile, "%ld\n", (long)pid) < 0) {
|
|
(*report)("fprintf() to pid file '%s' failed", filename);
|
|
(void)fclose(lockfile);
|
|
cleanup_pidfile();
|
|
return;
|
|
}
|
|
if (fflush(lockfile) == EOF) {
|
|
(*report)("fflush() to pid file '%s' failed", filename);
|
|
(void)fclose(lockfile);
|
|
cleanup_pidfile();
|
|
return;
|
|
}
|
|
(void)fclose(lockfile);
|
|
}
|
|
|
|
void
|
|
ns_os_shutdown(void) {
|
|
closelog();
|
|
cleanup_pidfile();
|
|
}
|
|
|
|
isc_result_t
|
|
ns_os_gethostname(char *buf, size_t len) {
|
|
int n;
|
|
|
|
n = gethostname(buf, len);
|
|
return ((n == 0) ? ISC_R_SUCCESS : ISC_R_FAILURE);
|
|
}
|
|
|
|
static char *
|
|
next_token(char **stringp, const char *delim) {
|
|
char *res;
|
|
|
|
do {
|
|
res = strsep(stringp, delim);
|
|
if (res == NULL)
|
|
break;
|
|
} while (*res == '\0');
|
|
return (res);
|
|
}
|
|
|
|
void
|
|
ns_os_shutdownmsg(char *command, isc_buffer_t *text) {
|
|
char *input, *ptr;
|
|
unsigned int n;
|
|
pid_t pid;
|
|
|
|
input = command;
|
|
|
|
/* Skip the command name. */
|
|
ptr = next_token(&input, " \t");
|
|
if (ptr == NULL)
|
|
return;
|
|
|
|
ptr = next_token(&input, " \t");
|
|
if (ptr == NULL)
|
|
return;
|
|
|
|
if (strcmp(ptr, "-p") != 0)
|
|
return;
|
|
|
|
#ifdef HAVE_LINUXTHREADS
|
|
pid = mainpid;
|
|
#else
|
|
pid = getpid();
|
|
#endif
|
|
|
|
n = snprintf((char *)isc_buffer_used(text),
|
|
isc_buffer_availablelength(text),
|
|
"pid: %ld", (long)pid);
|
|
/* Only send a message if it is complete. */
|
|
if (n > 0 && n < isc_buffer_availablelength(text))
|
|
isc_buffer_add(text, n);
|
|
}
|
|
|
|
void
|
|
ns_os_tzset(void) {
|
|
#ifdef HAVE_TZSET
|
|
tzset();
|
|
#endif
|
|
}
|