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Split off timestamp functions into their own source file.

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This commit is contained in:
Todd C. Miller
2012-09-27 10:21:13 -04:00
parent 05896f9cfc
commit 0fa33ccf0f
6 changed files with 535 additions and 439 deletions
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2
MANIFEST
View File

@@ -274,6 +274,8 @@ plugins/sudoers/sudoers2ldif
plugins/sudoers/sudoers_version.h
plugins/sudoers/sudoreplay.c
plugins/sudoers/testsudoers.c
plugins/sudoers/timestamp.c
plugins/sudoers/timestamp.h
plugins/sudoers/timestr.c
plugins/sudoers/toke.c
plugins/sudoers/toke.h

13
plugins/sudoers/Makefile.in
View File

@@ -130,7 +130,7 @@ LIBPARSESUDOERS_OBJS = alias.lo audit.lo defaults.lo gram.lo match.lo \
SUDOERS_OBJS = $(AUTH_OBJS) boottime.lo check.lo env.lo goodpath.lo \
group_plugin.lo find_path.lo interfaces.lo logging.lo \
logwrap.lo parse.lo set_perms.lo sudoers.lo sudo_nss.lo \
iolog.lo iolog_path.lo @SUDOERS_OBJS@
timestamp.lo iolog.lo iolog_path.lo @SUDOERS_OBJS@
VISUDO_OBJS = visudo.o goodpath.o find_path.o error.o
@@ -447,7 +447,8 @@ check.lo: $(srcdir)/check.c $(top_builddir)/config.h $(srcdir)/sudoers.h \
$(incdir)/missing.h $(incdir)/error.h $(incdir)/alloc.h \
$(incdir)/list.h $(incdir)/fileops.h $(srcdir)/defaults.h \
$(devdir)/def_data.h $(srcdir)/logging.h $(srcdir)/sudo_nss.h \
$(incdir)/sudo_plugin.h $(incdir)/sudo_debug.h $(incdir)/gettext.h
$(incdir)/sudo_plugin.h $(incdir)/sudo_debug.h $(incdir)/gettext.h \
$(srcdir)/timestamp.h
$(LIBTOOL) --mode=compile $(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(DEFS) $(srcdir)/check.c
check_addr.o: $(srcdir)/regress/parser/check_addr.c $(top_builddir)/config.h \
$(srcdir)/sudoers.h $(top_srcdir)/compat/stdbool.h \
@@ -789,6 +790,14 @@ testsudoers.o: $(srcdir)/testsudoers.c $(top_builddir)/config.h \
$(incdir)/sudo_conf.h $(incdir)/list.h $(incdir)/secure_path.h \
$(devdir)/gram.h
$(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(DEFS) $(srcdir)/testsudoers.c
timestamp.lo: $(srcdir)/timestamp.c $(top_builddir)/config.h \
$(srcdir)/sudoers.h $(top_srcdir)/compat/stdbool.h \
$(top_builddir)/pathnames.h $(incdir)/missing.h \
$(incdir)/error.h $(incdir)/alloc.h $(incdir)/list.h \
$(incdir)/fileops.h $(srcdir)/defaults.h $(devdir)/def_data.h \
$(srcdir)/logging.h $(srcdir)/sudo_nss.h $(incdir)/sudo_plugin.h \
$(incdir)/sudo_debug.h $(incdir)/gettext.h $(srcdir)/timestamp.h
$(LIBTOOL) --mode=compile $(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(DEFS) $(srcdir)/timestamp.c
timestr.lo: $(srcdir)/timestr.c $(top_builddir)/config.h $(incdir)/missing.h
$(LIBTOOL) --mode=compile $(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(DEFS) $(srcdir)/timestr.c
toke.lo: $(devdir)/toke.c $(top_builddir)/config.h $(top_builddir)/config.h \

450
plugins/sudoers/check.c
View File

@@ -1,5 +1,5 @@
/*
* Copyright (c) 1993-1996,1998-2005, 2007-2011
* Copyright (c) 1993-1996,1998-2005, 2007-2012
* Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
@@ -23,17 +23,6 @@
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/stat.h>
#ifdef __linux__
# include <sys/vfs.h>
#endif
#if defined(__sun) && defined(__SVR4)
# include <sys/statvfs.h>
#endif
#ifndef __TANDEM
# include <sys/file.h>
#endif
#include <stdio.h>
#ifdef STDC_HEADERS
# include <stdlib.h>
@@ -52,44 +41,16 @@
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif /* HAVE_UNISTD_H */
#if TIME_WITH_SYS_TIME
# include <time.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <pwd.h>
#include <grp.h>
#include "sudoers.h"
#include "timestamp.h"
/* Status codes for timestamp_status() */
#define TS_CURRENT 0
#define TS_OLD 1
#define TS_MISSING 2
#define TS_NOFILE 3
#define TS_ERROR 4
/* Flags for timestamp_status() */
#define TS_MAKE_DIRS 1
#define TS_REMOVE 2
/*
* Info stored in tty ticket from stat(2) to help with tty matching.
*/
static struct tty_info {
dev_t dev; /* ID of device tty resides on */
dev_t rdev; /* tty device ID */
ino_t ino; /* tty inode number */
struct timeval ctime; /* tty inode change time */
} tty_info;
static int build_timestamp(char **, char **);
static int timestamp_status(char *, char *, char *, int);
static char *expand_prompt(char *, char *, char *);
static void lecture(int);
static void update_timestamp(char *, char *);
static bool tty_is_devpts(const char *);
static bool display_lecture(int);
static struct passwd *get_authpw(void);
/*
@@ -100,10 +61,7 @@ int
check_user(int validated, int mode)
{
struct passwd *auth_pw;
char *timestampdir = NULL;
char *timestampfile = NULL;
char *prompt;
struct stat sb;
int status, rval = true;
debug_decl(check_user, SUDO_DEBUG_AUTH)
@@ -138,22 +96,12 @@ check_user(int validated, int mode)
if (ISSET(mode, MODE_IGNORE_TICKET))
SET(validated, FLAG_CHECK_USER);
/* Stash the tty's ctime for tty ticket comparison. */
if (def_tty_tickets && user_ttypath && stat(user_ttypath, &sb) == 0) {
tty_info.dev = sb.st_dev;
tty_info.ino = sb.st_ino;
tty_info.rdev = sb.st_rdev;
if (tty_is_devpts(user_ttypath))
ctim_get(&sb, &tty_info.ctime);
}
if (build_timestamp(&timestampdir, &timestampfile) == -1) {
if (build_timestamp() == -1) {
rval = -1;
goto done;
}
status = timestamp_status(timestampdir, timestampfile, user_name,
TS_MAKE_DIRS);
status = timestamp_status(TS_MAKE_DIRS);
if (status != TS_CURRENT || ISSET(validated, FLAG_CHECK_USER)) {
/* Bail out if we are non-interactive and a password is required */
@@ -165,7 +113,7 @@ check_user(int validated, int mode)
}
/* XXX - should not lecture if askpass helper is being used. */
lecture(status);
display_lecture(status);
/* Expand any escapes in the prompt. */
prompt = expand_prompt(user_prompt ? user_prompt : def_passprompt,
@@ -176,9 +124,7 @@ check_user(int validated, int mode)
/* Only update timestamp if user was validated. */
if (rval == true && ISSET(validated, VALIDATE_OK) &&
!ISSET(mode, MODE_IGNORE_TICKET) && status != TS_ERROR)
update_timestamp(timestampdir, timestampfile);
efree(timestampdir);
efree(timestampfile);
update_timestamp();
done:
sudo_auth_cleanup(auth_pw);
@@ -195,10 +141,11 @@ done:
" #3) With great power comes great responsibility.\n\n"
/*
* Standard sudo lecture.
* Display sudo lecture (standard or custom).
* Returns true if the user was lectured, else false.
*/
static void
lecture(int status)
static bool
display_lecture(int status)
{
FILE *fp;
char buf[BUFSIZ];
@@ -209,7 +156,7 @@ lecture(int status)
if (def_lecture == never ||
(def_lecture == once && status != TS_MISSING && status != TS_ERROR))
debug_return;
debug_return_int(false);
memset(&msg, 0, sizeof(msg));
memset(&repl, 0, sizeof(repl));
@@ -227,49 +174,7 @@ lecture(int status)
msg.msg = _(DEFAULT_LECTURE);
sudo_conv(1, &msg, &repl);
}
debug_return;
}
/*
* Update the time on the timestamp file/dir or create it if necessary.
*/
static void
update_timestamp(char *timestampdir, char *timestampfile)
{
debug_decl(update_timestamp, SUDO_DEBUG_AUTH)
/* If using tty timestamps but we have no tty there is nothing to do. */
if (def_tty_tickets && !user_ttypath)
debug_return;
if (timestamp_uid != 0)
set_perms(PERM_TIMESTAMP);
if (timestampfile) {
/*
* Store tty info in timestamp file
*/
int fd = open(timestampfile, O_WRONLY|O_CREAT, 0600);
if (fd == -1)
log_error(USE_ERRNO, _("unable to open %s"), timestampfile);
else {
lock_file(fd, SUDO_LOCK);
if (write(fd, &tty_info, sizeof(tty_info)) != sizeof(tty_info)) {
log_error(USE_ERRNO, _("unable to write to %s"),
timestampfile);
}
close(fd);
}
} else {
if (touch(-1, timestampdir, NULL) == -1) {
if (mkdir(timestampdir, 0700) == -1) {
log_error(USE_ERRNO, _("unable to mkdir %s"),
timestampdir);
}
}
}
if (timestamp_uid != 0)
restore_perms();
debug_return;
debug_return_int(true);
}
/*
@@ -414,335 +319,6 @@ user_is_exempt(void)
debug_return_bool(rval);
}
/*
* Fills in timestampdir as well as timestampfile if using tty tickets.
*/
static int
build_timestamp(char **timestampdir, char **timestampfile)
{
char *dirparent;
int len;
debug_decl(build_timestamp, SUDO_DEBUG_AUTH)
dirparent = def_timestampdir;
*timestampfile = NULL;
len = easprintf(timestampdir, "%s/%s", dirparent, user_name);
if (len >= PATH_MAX)
goto bad;
/*
* Timestamp file may be a file in the directory or NUL to use
* the directory as the timestamp.
*/
if (def_tty_tickets) {
char *p;
if ((p = strrchr(user_tty, '/')))
p++;
else
p = user_tty;
if (def_targetpw)
len = easprintf(timestampfile, "%s/%s/%s:%s", dirparent, user_name,
p, runas_pw->pw_name);
else
len = easprintf(timestampfile, "%s/%s/%s", dirparent, user_name, p);
if (len >= PATH_MAX)
goto bad;
} else if (def_targetpw) {
len = easprintf(timestampfile, "%s/%s/%s", dirparent, user_name,
runas_pw->pw_name);
if (len >= PATH_MAX)
goto bad;
} else
*timestampfile = NULL;
debug_return_int(len);
bad:
log_fatal(0, _("timestamp path too long: %s"),
*timestampfile ? *timestampfile : *timestampdir);
/* NOTREACHED */
debug_return_int(-1);
}
/*
* Check the timestamp file and directory and return their status.
*/
static int
timestamp_status(char *timestampdir, char *timestampfile, char *user, int flags)
{
struct stat sb;
struct timeval boottime, mtime;
time_t now;
char *dirparent = def_timestampdir;
int status = TS_ERROR; /* assume the worst */
debug_decl(timestamp_status, SUDO_DEBUG_AUTH)
if (timestamp_uid != 0)
set_perms(PERM_TIMESTAMP);
/*
* Sanity check dirparent and make it if it doesn't already exist.
* We start out assuming the worst (that the dir is not sane) and
* if it is ok upgrade the status to ``no timestamp file''.
* Note that we don't check the parent(s) of dirparent for
* sanity since the sudo dir is often just located in /tmp.
*/
if (lstat(dirparent, &sb) == 0) {
if (!S_ISDIR(sb.st_mode))
log_error(0, _("%s exists but is not a directory (0%o)"),
dirparent, (unsigned int) sb.st_mode);
else if (sb.st_uid != timestamp_uid)
log_error(0, _("%s owned by uid %u, should be uid %u"),
dirparent, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
else if ((sb.st_mode & 0000022))
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0700"),
dirparent, (unsigned int) sb.st_mode);
else {
if ((sb.st_mode & 0000777) != 0700)
(void) chmod(dirparent, 0700);
status = TS_MISSING;
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), dirparent);
} else {
/* No dirparent, try to make one. */
if (ISSET(flags, TS_MAKE_DIRS)) {
if (mkdir(dirparent, S_IRWXU))
log_error(USE_ERRNO, _("unable to mkdir %s"),
dirparent);
else
status = TS_MISSING;
}
}
if (status == TS_ERROR)
goto done;
/*
* Sanity check the user's ticket dir. We start by downgrading
* the status to TS_ERROR. If the ticket dir exists and is sane
* this will be upgraded to TS_OLD. If the dir does not exist,
* it will be upgraded to TS_MISSING.
*/
status = TS_ERROR; /* downgrade status again */
if (lstat(timestampdir, &sb) == 0) {
if (!S_ISDIR(sb.st_mode)) {
if (S_ISREG(sb.st_mode)) {
/* convert from old style */
if (unlink(timestampdir) == 0)
status = TS_MISSING;
} else
log_error(0, _("%s exists but is not a directory (0%o)"),
timestampdir, (unsigned int) sb.st_mode);
} else if (sb.st_uid != timestamp_uid)
log_error(0, _("%s owned by uid %u, should be uid %u"),
timestampdir, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
else if ((sb.st_mode & 0000022))
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0700"),
timestampdir, (unsigned int) sb.st_mode);
else {
if ((sb.st_mode & 0000777) != 0700)
(void) chmod(timestampdir, 0700);
status = TS_OLD; /* do date check later */
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), timestampdir);
} else
status = TS_MISSING;
/*
* If there is no user ticket dir, AND we are in tty ticket mode,
* AND the TS_MAKE_DIRS flag is set, create the user ticket dir.
*/
if (status == TS_MISSING && timestampfile && ISSET(flags, TS_MAKE_DIRS)) {
if (mkdir(timestampdir, S_IRWXU) == -1) {
status = TS_ERROR;
log_error(USE_ERRNO, _("unable to mkdir %s"), timestampdir);
}
}
/*
* Sanity check the tty ticket file if it exists.
*/
if (timestampfile && status != TS_ERROR) {
if (status != TS_MISSING)
status = TS_NOFILE; /* dir there, file missing */
if (def_tty_tickets && !user_ttypath)
goto done; /* no tty, always prompt */
if (lstat(timestampfile, &sb) == 0) {
if (!S_ISREG(sb.st_mode)) {
status = TS_ERROR;
log_error(0, _("%s exists but is not a regular file (0%o)"),
timestampfile, (unsigned int) sb.st_mode);
} else {
/* If bad uid or file mode, complain and kill the bogus file. */
if (sb.st_uid != timestamp_uid) {
log_error(0,
_("%s owned by uid %u, should be uid %u"),
timestampfile, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
(void) unlink(timestampfile);
} else if ((sb.st_mode & 0000022)) {
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0600"),
timestampfile, (unsigned int) sb.st_mode);
(void) unlink(timestampfile);
} else {
/* If not mode 0600, fix it. */
if ((sb.st_mode & 0000777) != 0600)
(void) chmod(timestampfile, 0600);
/*
* Check for stored tty info. If the file is zero-sized
* it is an old-style timestamp with no tty info in it.
* If removing, we don't care about the contents.
* The actual mtime check is done later.
*/
if (ISSET(flags, TS_REMOVE)) {
status = TS_OLD;
} else if (sb.st_size != 0) {
struct tty_info info;
int fd = open(timestampfile, O_RDONLY, 0644);
if (fd != -1) {
if (read(fd, &info, sizeof(info)) == sizeof(info) &&
memcmp(&info, &tty_info, sizeof(info)) == 0) {
status = TS_OLD;
}
close(fd);
}
}
}
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), timestampfile);
status = TS_ERROR;
}
}
/*
* If the file/dir exists and we are not removing it, check its mtime.
*/
if (status == TS_OLD && !ISSET(flags, TS_REMOVE)) {
mtim_get(&sb, &mtime);
/* Negative timeouts only expire manually (sudo -k). */
if (def_timestamp_timeout < 0 && mtime.tv_sec != 0)
status = TS_CURRENT;
else {
now = time(NULL);
if (def_timestamp_timeout &&
now - mtime.tv_sec < 60 * def_timestamp_timeout) {
/*
* Check for bogus time on the stampfile. The clock may
* have been set back or someone could be trying to spoof us.
*/
if (mtime.tv_sec > now + 60 * def_timestamp_timeout * 2) {
time_t tv_sec = (time_t)mtime.tv_sec;
log_error(0,
_("timestamp too far in the future: %20.20s"),
4 + ctime(&tv_sec));
if (timestampfile)
(void) unlink(timestampfile);
else
(void) rmdir(timestampdir);
status = TS_MISSING;
} else if (get_boottime(&boottime) && timevalcmp(&mtime, &boottime, <)) {
status = TS_OLD;
} else {
status = TS_CURRENT;
}
}
}
}
done:
if (timestamp_uid != 0)
restore_perms();
debug_return_int(status);
}
/*
* Remove the timestamp ticket file/dir.
*/
void
remove_timestamp(bool remove)
{
struct timeval tv;
char *timestampdir, *timestampfile, *path;
int status;
debug_decl(remove_timestamp, SUDO_DEBUG_AUTH)
if (build_timestamp(&timestampdir, &timestampfile) == -1)
debug_return;
status = timestamp_status(timestampdir, timestampfile, user_name,
TS_REMOVE);
if (status != TS_MISSING && status != TS_ERROR) {
path = timestampfile ? timestampfile : timestampdir;
if (remove) {
if (timestampfile)
status = unlink(timestampfile);
else
status = rmdir(timestampdir);
if (status == -1 && errno != ENOENT) {
log_error(0,
_("unable to remove %s (%s), will reset to the epoch"),
path, strerror(errno));
remove = false;
}
}
if (!remove) {
timevalclear(&tv);
if (touch(-1, path, &tv) == -1 && errno != ENOENT)
error(1, _("unable to reset %s to the epoch"), path);
}
}
efree(timestampdir);
efree(timestampfile);
debug_return;
}
/*
* Returns true if tty lives on a devpts, /dev or /devices filesystem, else
* false. Unlike most filesystems, the ctime of devpts nodes is not updated
* when the device node is written to, only when the inode's status changes,
* typically via the chmod, chown, link, rename, or utimes system calls.
* Since the ctime is "stable" in this case, we can stash it the tty ticket
* file and use it to determine whether the tty ticket file is stale.
*/
static bool
tty_is_devpts(const char *tty)
{
bool retval = false;
#ifdef __linux__
struct statfs sfs;
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
#ifndef DEVPTS_SUPER_MAGIC
# define DEVPTS_SUPER_MAGIC 0x1cd1
#endif
if (statfs(tty, &sfs) == 0) {
if (sfs.f_type == DEVPTS_SUPER_MAGIC)
retval = true;
}
#elif defined(__sun) && defined(__SVR4)
struct statvfs sfs;
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
if (statvfs(tty, &sfs) == 0) {
if (strcmp(sfs.f_fstr, "dev") == 0 || strcmp(sfs.f_fstr, "devices") == 0)
retval = true;
}
#else
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
#endif /* __linux__ */
debug_return_bool(retval);
}
/*
* Get passwd entry for the user we are going to authenticate as.
* By default, this is the user invoking sudo. In the most common

11
plugins/sudoers/defaults.c
View File

@@ -500,10 +500,21 @@ update_defaults(int what)
rc = false;
break;
case DEFAULTS_USER:
#if 1
if (ISSET(what, SETDEF_USER)) {
int m;
m = userlist_matches(sudo_user.pw, &def->binding);
if (m == ALLOW) {
if (!set_default(def->var, def->val, def->op))
rc = false;
}
}
#else
if (ISSET(what, SETDEF_USER) &&
userlist_matches(sudo_user.pw, &def->binding) == ALLOW &&
!set_default(def->var, def->val, def->op))
rc = false;
#endif
break;
case DEFAULTS_RUNAS:
if (ISSET(what, SETDEF_RUNAS) &&

448
plugins/sudoers/timestamp.c Normal file
View File

@@ -0,0 +1,448 @@
/*
* Copyright (c) 1993-1996,1998-2005, 2007-2012
* Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
*
* Sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F39502-99-1-0512.
*/
#include <config.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/stat.h>
#ifdef __linux__
# include <sys/vfs.h>
#endif
#if defined(__sun) && defined(__SVR4)
# include <sys/statvfs.h>
#endif
#ifndef __TANDEM
# include <sys/file.h>
#endif
#include <stdio.h>
#ifdef STDC_HEADERS
# include <stdlib.h>
# include <stddef.h>
#else
# ifdef HAVE_STDLIB_H
# include <stdlib.h>
# endif
#endif /* STDC_HEADERS */
#ifdef HAVE_STRING_H
# include <string.h>
#endif /* HAVE_STRING_H */
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif /* HAVE_UNISTD_H */
#if TIME_WITH_SYS_TIME
# include <time.h>
#endif
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <pwd.h>
#include <grp.h>
#include "sudoers.h"
#include "timestamp.h"
static bool tty_is_devpts(const char *);
static struct sudo_tty_info tty_info;
static char timestampdir[PATH_MAX];
static char timestampfile[PATH_MAX];
/*
* Fills in timestampdir as well as timestampfile if using tty tickets.
*/
int
build_timestamp(void)
{
char *dirparent;
struct stat sb;
int len;
debug_decl(build_timestamp, SUDO_DEBUG_AUTH)
/* Stash the tty's ctime for tty ticket comparison. */
if (def_tty_tickets && user_ttypath && stat(user_ttypath, &sb) == 0) {
tty_info.dev = sb.st_dev;
tty_info.ino = sb.st_ino;
tty_info.rdev = sb.st_rdev;
if (tty_is_devpts(user_ttypath))
ctim_get(&sb, &tty_info.ctime);
}
dirparent = def_timestampdir;
timestampfile[0] = '\0';
len = snprintf(timestampdir, sizeof(timestampdir), "%s/%s", dirparent,
user_name);
if (len <= 0 || len >= sizeof(timestampdir))
goto bad;
/*
* Timestamp file may be a file in the directory or NUL to use
* the directory as the timestamp.
*/
if (def_tty_tickets) {
char *p;
if ((p = strrchr(user_tty, '/')))
p++;
else
p = user_tty;
if (def_targetpw)
len = snprintf(timestampfile, sizeof(timestampfile), "%s/%s/%s:%s",
dirparent, user_name, p, runas_pw->pw_name);
else
len = snprintf(timestampfile, sizeof(timestampfile), "%s/%s/%s",
dirparent, user_name, p);
if (len <= 0 || len >= sizeof(timestampfile))
goto bad;
} else if (def_targetpw) {
len = snprintf(timestampfile, sizeof(timestampfile), "%s/%s/%s",
dirparent, user_name, runas_pw->pw_name);
if (len <= 0 || len >= sizeof(timestampfile))
goto bad;
}
debug_return_int(len);
bad:
log_fatal(0, _("timestamp path too long: %s"),
*timestampfile ? timestampfile : timestampdir);
/* NOTREACHED */
debug_return_int(-1);
}
/*
* Update the time on the timestamp file/dir or create it if necessary.
*/
bool
update_timestamp(void)
{
debug_decl(update_timestamp, SUDO_DEBUG_AUTH)
/* If using tty timestamps but we have no tty there is nothing to do. */
if (def_tty_tickets && !user_ttypath)
debug_return_bool(false);
if (timestamp_uid != 0)
set_perms(PERM_TIMESTAMP);
if (*timestampfile) {
/*
* Store tty info in timestamp file
*/
int fd = open(timestampfile, O_WRONLY|O_CREAT, 0600);
if (fd == -1)
log_error(USE_ERRNO, _("unable to open %s"), timestampfile);
else {
lock_file(fd, SUDO_LOCK);
if (write(fd, &tty_info, sizeof(tty_info)) != sizeof(tty_info))
log_error(USE_ERRNO, _("unable to write to %s"), timestampfile);
close(fd);
}
} else {
if (touch(-1, timestampdir, NULL) == -1) {
if (mkdir(timestampdir, 0700) == -1) {
log_error(USE_ERRNO, _("unable to mkdir %s"),
timestampdir);
}
}
}
if (timestamp_uid != 0)
restore_perms();
debug_return_bool(true);
}
/*
* Check the timestamp file and directory and return their status.
*/
int
timestamp_status(int flags)
{
struct stat sb;
struct timeval boottime, mtime;
time_t now;
char *dirparent = def_timestampdir;
int status = TS_ERROR; /* assume the worst */
debug_decl(timestamp_status, SUDO_DEBUG_AUTH)
if (timestamp_uid != 0)
set_perms(PERM_TIMESTAMP);
/*
* Sanity check dirparent and make it if it doesn't already exist.
* We start out assuming the worst (that the dir is not sane) and
* if it is ok upgrade the status to ``no timestamp file''.
* Note that we don't check the parent(s) of dirparent for
* sanity since the sudo dir is often just located in /tmp.
*/
if (lstat(dirparent, &sb) == 0) {
if (!S_ISDIR(sb.st_mode))
log_error(0, _("%s exists but is not a directory (0%o)"),
dirparent, (unsigned int) sb.st_mode);
else if (sb.st_uid != timestamp_uid)
log_error(0, _("%s owned by uid %u, should be uid %u"),
dirparent, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
else if ((sb.st_mode & 0000022))
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0700"),
dirparent, (unsigned int) sb.st_mode);
else {
if ((sb.st_mode & 0000777) != 0700)
(void) chmod(dirparent, 0700);
status = TS_MISSING;
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), dirparent);
} else {
/* No dirparent, try to make one. */
if (ISSET(flags, TS_MAKE_DIRS)) {
if (mkdir(dirparent, S_IRWXU))
log_error(USE_ERRNO, _("unable to mkdir %s"),
dirparent);
else
status = TS_MISSING;
}
}
if (status == TS_ERROR)
goto done;
/*
* Sanity check the user's ticket dir. We start by downgrading
* the status to TS_ERROR. If the ticket dir exists and is sane
* this will be upgraded to TS_OLD. If the dir does not exist,
* it will be upgraded to TS_MISSING.
*/
status = TS_ERROR; /* downgrade status again */
if (lstat(timestampdir, &sb) == 0) {
if (!S_ISDIR(sb.st_mode)) {
if (S_ISREG(sb.st_mode)) {
/* convert from old style */
if (unlink(timestampdir) == 0)
status = TS_MISSING;
} else
log_error(0, _("%s exists but is not a directory (0%o)"),
timestampdir, (unsigned int) sb.st_mode);
} else if (sb.st_uid != timestamp_uid)
log_error(0, _("%s owned by uid %u, should be uid %u"),
timestampdir, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
else if ((sb.st_mode & 0000022))
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0700"),
timestampdir, (unsigned int) sb.st_mode);
else {
if ((sb.st_mode & 0000777) != 0700)
(void) chmod(timestampdir, 0700);
status = TS_OLD; /* do date check later */
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), timestampdir);
} else
status = TS_MISSING;
/*
* If there is no user ticket dir, AND we are in tty ticket mode,
* AND the TS_MAKE_DIRS flag is set, create the user ticket dir.
*/
if (status == TS_MISSING && *timestampfile && ISSET(flags, TS_MAKE_DIRS)) {
if (mkdir(timestampdir, S_IRWXU) == -1) {
status = TS_ERROR;
log_error(USE_ERRNO, _("unable to mkdir %s"), timestampdir);
}
}
/*
* Sanity check the tty ticket file if it exists.
*/
if (*timestampfile && status != TS_ERROR) {
if (status != TS_MISSING)
status = TS_NOFILE; /* dir there, file missing */
if (def_tty_tickets && !user_ttypath)
goto done; /* no tty, always prompt */
if (lstat(timestampfile, &sb) == 0) {
if (!S_ISREG(sb.st_mode)) {
status = TS_ERROR;
log_error(0, _("%s exists but is not a regular file (0%o)"),
timestampfile, (unsigned int) sb.st_mode);
} else {
/* If bad uid or file mode, complain and kill the bogus file. */
if (sb.st_uid != timestamp_uid) {
log_error(0,
_("%s owned by uid %u, should be uid %u"),
timestampfile, (unsigned int) sb.st_uid,
(unsigned int) timestamp_uid);
(void) unlink(timestampfile);
} else if ((sb.st_mode & 0000022)) {
log_error(0,
_("%s writable by non-owner (0%o), should be mode 0600"),
timestampfile, (unsigned int) sb.st_mode);
(void) unlink(timestampfile);
} else {
/* If not mode 0600, fix it. */
if ((sb.st_mode & 0000777) != 0600)
(void) chmod(timestampfile, 0600);
/*
* Check for stored tty info. If the file is zero-sized
* it is an old-style timestamp with no tty info in it.
* If removing, we don't care about the contents.
* The actual mtime check is done later.
*/
if (ISSET(flags, TS_REMOVE)) {
status = TS_OLD;
} else if (sb.st_size != 0) {
struct sudo_tty_info info;
int fd = open(timestampfile, O_RDONLY, 0644);
if (fd != -1) {
if (read(fd, &info, sizeof(info)) == sizeof(info) &&
memcmp(&info, &tty_info, sizeof(info)) == 0) {
status = TS_OLD;
}
close(fd);
}
}
}
}
} else if (errno != ENOENT) {
log_error(USE_ERRNO, _("unable to stat %s"), timestampfile);
status = TS_ERROR;
}
}
/*
* If the file/dir exists and we are not removing it, check its mtime.
*/
if (status == TS_OLD && !ISSET(flags, TS_REMOVE)) {
mtim_get(&sb, &mtime);
/* Negative timeouts only expire manually (sudo -k). */
if (def_timestamp_timeout < 0 && mtime.tv_sec != 0)
status = TS_CURRENT;
else {
now = time(NULL);
if (def_timestamp_timeout &&
now - mtime.tv_sec < 60 * def_timestamp_timeout) {
/*
* Check for bogus time on the stampfile. The clock may
* have been set back or someone could be trying to spoof us.
*/
if (mtime.tv_sec > now + 60 * def_timestamp_timeout * 2) {
time_t tv_sec = (time_t)mtime.tv_sec;
log_error(0,
_("timestamp too far in the future: %20.20s"),
4 + ctime(&tv_sec));
if (*timestampfile)
(void) unlink(timestampfile);
else
(void) rmdir(timestampdir);
status = TS_MISSING;
} else if (get_boottime(&boottime) && timevalcmp(&mtime, &boottime, <)) {
status = TS_OLD;
} else {
status = TS_CURRENT;
}
}
}
}
done:
if (timestamp_uid != 0)
restore_perms();
debug_return_int(status);
}
/*
* Remove the timestamp ticket file/dir.
*/
void
remove_timestamp(bool remove)
{
struct timeval tv;
char *path;
int status;
debug_decl(remove_timestamp, SUDO_DEBUG_AUTH)
if (build_timestamp() == -1)
debug_return;
status = timestamp_status(TS_REMOVE);
if (status != TS_MISSING && status != TS_ERROR) {
path = *timestampfile ? timestampfile : timestampdir;
if (remove) {
if (*timestampfile)
status = unlink(timestampfile);
else
status = rmdir(timestampdir);
if (status == -1 && errno != ENOENT) {
log_error(0,
_("unable to remove %s (%s), will reset to the epoch"),
path, strerror(errno));
remove = false;
}
}
if (!remove) {
timevalclear(&tv);
if (touch(-1, path, &tv) == -1 && errno != ENOENT)
error(1, _("unable to reset %s to the epoch"), path);
}
}
debug_return;
}
/*
* Returns true if tty lives on a devpts, /dev or /devices filesystem, else
* false. Unlike most filesystems, the ctime of devpts nodes is not updated
* when the device node is written to, only when the inode's status changes,
* typically via the chmod, chown, link, rename, or utimes system calls.
* Since the ctime is "stable" in this case, we can stash it the tty ticket
* file and use it to determine whether the tty ticket file is stale.
*/
static bool
tty_is_devpts(const char *tty)
{
bool retval = false;
#ifdef __linux__
struct statfs sfs;
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
#ifndef DEVPTS_SUPER_MAGIC
# define DEVPTS_SUPER_MAGIC 0x1cd1
#endif
if (statfs(tty, &sfs) == 0) {
if (sfs.f_type == DEVPTS_SUPER_MAGIC)
retval = true;
}
#elif defined(__sun) && defined(__SVR4)
struct statvfs sfs;
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
if (statvfs(tty, &sfs) == 0) {
if (strcmp(sfs.f_fstr, "dev") == 0 || strcmp(sfs.f_fstr, "devices") == 0)
retval = true;
}
#else
debug_decl(tty_is_devpts, SUDO_DEBUG_PTY)
#endif /* __linux__ */
debug_return_bool(retval);
}

50
plugins/sudoers/timestamp.h Normal file
View File

@@ -0,0 +1,50 @@
/*
* Copyright (c) 1993-1996,1998-2005, 2007-2012
* Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and 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 THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
*
* Sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F39502-99-1-0512.
*/
#ifndef _SUDO_TIMESTAMP_H
#define _SUDO_TIMESTAMP_H
/* Status codes for timestamp_status() */
#define TS_CURRENT 0
#define TS_OLD 1
#define TS_MISSING 2
#define TS_NOFILE 3
#define TS_ERROR 4
/* Flags for timestamp_status() */
#define TS_MAKE_DIRS 1
#define TS_REMOVE 2
/*
* Info stored in tty ticket from stat(2) to help with tty matching.
*/
struct sudo_tty_info {
dev_t dev; /* ID of device tty resides on */
dev_t rdev; /* tty device ID */
ino_t ino; /* tty inode number */
struct timeval ctime; /* tty inode change time */
};
bool update_timestamp(void);
int build_timestamp(void);
int timestamp_status(int);
#endif /* _SUDO_TIMESTAMP_H */