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-rw-r--r--bin/named/unix/os.c1114
1 files changed, 1114 insertions, 0 deletions
diff --git a/bin/named/unix/os.c b/bin/named/unix/os.c
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index 0000000..809cede
--- /dev/null
+++ b/bin/named/unix/os.c
@@ -0,0 +1,1114 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * 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 http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file */
+
+#include <config.h>
+#include <stdarg.h>
+#include <stdbool.h>
+
+#include <sys/types.h> /* dev_t FreeBSD 2.1 */
+#include <sys/stat.h>
+#ifdef HAVE_UNAME
+#include <sys/utsname.h>
+#endif
+
+#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/globals.h>
+#include <named/main.h>
+#include <named/os.h>
+#ifdef HAVE_LIBSCF
+#include <named/ns_smf_globals.h>
+#endif
+
+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
+
+/*
+ * 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 bool done_setuid = false;
+static int dfd[2] = { -1, -1 };
+
+#ifdef HAVE_LINUX_CAPABILITY_H
+
+static bool non_root = false;
+static bool non_root_caps = false;
+
+#ifdef HAVE_SYS_CAPABILITY_H
+#include <sys/capability.h>
+#else
+#ifdef HAVE_LINUX_TYPES_H
+#include <linux/types.h>
+#endif
+/*%
+ * 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 { \
+ 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) { \
+ 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 { \
+ if (curcaps & (1 << (flag))) { \
+ caps |= (1 << (flag)); \
+ } \
+ } while (0)
+#define INIT_CAP do { caps = 0; } while (0)
+#endif /* HAVE_LIBCAP */
+
+#ifndef HAVE_LIBCAP
+/*%
+ * Store the bitmask representing the permitted capability set in 'capsp'. To
+ * match libcap-enabled behavior, capget() syscall errors are not reported,
+ * they just cause 'capsp' to be set to 0, which effectively prevents any
+ * capability from being subsequently requested.
+ */
+static void
+linux_getpermittedcaps(cap_t *capsp) {
+ struct __user_cap_header_struct caphead;
+ struct __user_cap_data_struct curcaps;
+
+ memset(&caphead, 0, sizeof(caphead));
+ caphead.version = _LINUX_CAPABILITY_VERSION;
+ caphead.pid = 0;
+ memset(&curcaps, 0, sizeof(curcaps));
+ syscall(SYS_capget, &caphead, &curcaps);
+
+ *capsp = curcaps.permitted;
+}
+#endif /* HAVE_LIBCAP */
+
+static void
+linux_initialprivs(void) {
+ cap_t curcaps;
+ cap_t caps;
+#ifdef HAVE_LIBCAP
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+#else
+ linux_getpermittedcaps(&curcaps);
+#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 curcaps;
+ cap_t caps;
+#ifdef HAVE_LIBCAP
+ cap_value_t capval;
+ char strbuf[ISC_STRERRORSIZE];
+ int err;
+#else
+ linux_getpermittedcaps(&curcaps);
+#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 = true;
+ if (getuid() != 0)
+ non_root = 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 && !ns_g_keepstderr) {
+ (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 bool
+all_digits(const char *s) {
+ if (*s == '\0')
+ return (false);
+ while (*s != '\0') {
+ if (!isdigit((*s)&0xff))
+ return (false);
+ s++;
+ }
+ return (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 = 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
+}
+
+uid_t
+ns_os_uid(void) {
+ if (runas_pw == NULL)
+ return (0);
+ return (runas_pw->pw_uid);
+}
+
+void
+ns_os_adjustnofile(void) {
+#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, 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)
+ ns_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)
+ ns_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) {
+ 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) {
+#if defined(HAVE_SETEGID) || defined(HAVE_SETRESGID)
+ char strbuf[ISC_STRERRORSIZE];
+#endif
+#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, 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) {
+ 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, 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, 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, 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, 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 ? 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;
+ }
+
+ fh = ns_os_openfile(filename, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
+ first_time);
+ if (fh == NULL) {
+ cleanup_pidfile();
+ return;
+ }
+#ifdef HAVE_LINUXTHREADS
+ pid = mainpid;
+#else
+ pid = getpid();
+#endif
+ 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
+ns_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) {
+ isc__strerror(errno, strbuf, sizeof(strbuf));
+ ns_main_earlyfatal("couldn't allocate memory for '%s': %s",
+ filename, strbuf);
+ } else {
+ int ret = mkdirpath(lockfile, ns_main_earlywarning);
+ if (ret == -1) {
+ ns_main_earlywarning("couldn't create '%s'", filename);
+ cleanup_lockfile();
+ return (false);
+ }
+ }
+
+ /*
+ * ns_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
+ns_os_shutdown(void) {
+ closelog();
+ cleanup_pidfile();
+ cleanup_lockfile();
+}
+
+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
+}
+
+static char unamebuf[BUFSIZ];
+static 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);
+#else
+ snprintf(unamebuf, sizeof(unamebuf), "unknown architecture");
+#endif
+ unamep = unamebuf;
+}
+
+char *
+ns_os_uname(void) {
+ if (unamep == NULL)
+ getuname();
+ return (unamep);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-03 21:13:20 +0000