/*
- * Copyright (c) 1993-1996,1998-2005 Todd C. Miller <Todd.Miller@courtesan.com>
+ * Copyright (c) 1993-1996,1998-2005, 2007-2010
+ * 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
#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
#endif /* STDC_HEADERS */
#ifdef HAVE_STRING_H
# include <string.h>
-#else
-# ifdef HAVE_STRINGS_H
-# include <strings.h>
-# endif
#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 */
-#ifdef HAVE_ERR_H
-# include <err.h>
-#else
-# include "emul/err.h"
-#endif /* HAVE_ERR_H */
+#if TIME_WITH_SYS_TIME
+# include <time.h>
+#endif
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
-#include <time.h>
#include <pwd.h>
#include <grp.h>
-#ifndef HAVE_TIMESPEC
-# include <emul/timespec.h>
-#endif
#include "sudo.h"
-#ifndef lint
-__unused static const char rcsid[] = "$Sudo: check.c,v 1.223.2.9 2007/07/06 19:52:13 millert Exp $";
-#endif /* lint */
-
/* Status codes for timestamp_status() */
#define TS_CURRENT 0
#define TS_OLD 1
#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 void build_timestamp __P((char **, char **));
static int timestamp_status __P((char *, char *, char *, int));
static char *expand_prompt __P((char *, char *, char *));
static void lecture __P((int));
static void update_timestamp __P((char *, char *));
+static int tty_is_devpts __P((const char *));
/*
* This function only returns if the user can successfully
* verify who he/she is.
*/
void
-check_user(validated)
+check_user(validated, mode)
int validated;
+ int mode;
{
char *timestampdir = NULL;
char *timestampfile = NULL;
char *prompt;
+ struct stat sb;
int status;
- if (user_uid == 0 || user_uid == runas_pw->pw_uid || user_is_exempt())
- return;
+ /* 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);
+ }
+
+ /* Always prompt for a password when -k was specified with the command. */
+ if (ISSET(mode, MODE_INVALIDATE)) {
+ SET(validated, FLAG_CHECK_USER);
+ } else {
+ if (user_uid == 0 || user_uid == runas_pw->pw_uid || user_is_exempt())
+ return;
+ }
build_timestamp(×tampdir, ×tampfile);
status = timestamp_status(timestampdir, timestampfile, user_name,
TS_MAKE_DIRS);
+
if (status != TS_CURRENT || ISSET(validated, FLAG_CHECK_USER)) {
- lecture(status);
+ /* Bail out if we are non-interactive and a password is required */
+ if (ISSET(mode, MODE_NONINTERACTIVE))
+ errorx(1, "sorry, a password is required to run %s", getprogname());
+
+ /* If user specified -A, make sure we have an askpass helper. */
+ if (ISSET(tgetpass_flags, TGP_ASKPASS)) {
+ if (user_askpass == NULL)
+ log_error(NO_MAIL,
+ "no askpass program specified, try setting SUDO_ASKPASS");
+ } else if (!ISSET(tgetpass_flags, TGP_STDIN)) {
+ /* If no tty but DISPLAY is set, use askpass if we have it. */
+ if (!user_ttypath && !tty_present()) {
+ if (user_askpass && user_display && *user_display != '\0') {
+ SET(tgetpass_flags, TGP_ASKPASS);
+ } else if (!def_visiblepw) {
+ log_error(NO_MAIL,
+ "no tty present and no askpass program specified");
+ }
+ }
+ }
+
+ if (!ISSET(tgetpass_flags, TGP_ASKPASS))
+ lecture(status);
/* Expand any escapes in the prompt. */
prompt = expand_prompt(user_prompt ? user_prompt : def_passprompt,
verify_user(auth_pw, prompt);
}
/* Only update timestamp if user was validated. */
- if (status != TS_ERROR && ISSET(validated, VALIDATE_OK))
+ if (ISSET(validated, VALIDATE_OK) && !ISSET(mode, MODE_INVALIDATE) && status != TS_ERROR)
update_timestamp(timestampdir, timestampfile);
efree(timestampdir);
efree(timestampfile);
/*
* Standard sudo lecture.
- * TODO: allow the user to specify a file name instead.
*/
static void
lecture(status)
char *timestampdir;
char *timestampfile;
{
+ /* If using tty timestamps but we have no tty there is nothing to do. */
+ if (def_tty_tickets && !user_ttypath)
+ return;
+
if (timestamp_uid != 0)
set_perms(PERM_TIMESTAMP);
- if (touch(-1, timestampfile ? timestampfile : timestampdir, NULL) == -1) {
- if (timestampfile) {
- int fd = open(timestampfile, O_WRONLY|O_CREAT|O_TRUNC, 0600);
-
- if (fd == -1)
- log_error(NO_EXIT|USE_ERRNO, "Can't open %s", timestampfile);
- else
- close(fd);
- } else {
+ if (timestampfile) {
+ /*
+ * Store tty info in timestamp file
+ */
+ int fd = open(timestampfile, O_WRONLY|O_CREAT, 0600);
+ if (fd == -1)
+ log_error(NO_EXIT|USE_ERRNO, "Can't open %s", timestampfile);
+ else {
+ lock_file(fd, SUDO_LOCK);
+ write(fd, &tty_info, sizeof(tty_info));
+ close(fd);
+ }
+ } else {
+ if (touch(-1, timestampdir, NULL) == -1) {
if (mkdir(timestampdir, 0700) == -1)
log_error(NO_EXIT|USE_ERRNO, "Can't mkdir %s", timestampdir);
}
len += strlen(user_host) - 2;
subst = 1;
break;
+ case 'p':
+ p++;
+ if (def_rootpw)
+ len += 2;
+ else if (def_targetpw || def_runaspw)
+ len += strlen(runas_pw->pw_name) - 2;
+ else
+ len += strlen(user_name) - 2;
+ subst = 1;
+ break;
case 'u':
p++;
len += strlen(user_name) - 2;
break;
case 'U':
p++;
- len += strlen(*user_runas) - 2;
+ len += strlen(runas_pw->pw_name) - 2;
subst = 1;
break;
case '%':
goto oflow;
np += n;
continue;
+ case 'p':
+ p++;
+ if (def_rootpw)
+ n = strlcpy(np, "root", np - endp);
+ else if (def_targetpw || def_runaspw)
+ n = strlcpy(np, runas_pw->pw_name, np - endp);
+ else
+ n = strlcpy(np, user_name, np - endp);
+ if (n >= np - endp)
+ goto oflow;
+ np += n;
+ continue;
case 'u':
p++;
n = strlcpy(np, user_name, np - endp);
continue;
case 'U':
p++;
- n = strlcpy(np, *user_runas, np - endp);
+ n = strlcpy(np, runas_pw->pw_name, np - endp);
if (n >= np - endp)
goto oflow;
np += n;
oflow:
/* We pre-allocate enough space, so this should never happen. */
- errx(1, "internal error, expand_prompt() overflow");
+ errorx(1, "internal error, expand_prompt() overflow");
}
/*
int
user_is_exempt()
{
- struct group *grp;
- char **gr_mem;
-
if (!def_exempt_group)
return(FALSE);
-
- if (!(grp = getgrnam(def_exempt_group)))
- return(FALSE);
-
- if (user_gid == grp->gr_gid)
- return(TRUE);
-
- for (gr_mem = grp->gr_mem; *gr_mem; gr_mem++) {
- if (strcmp(user_name, *gr_mem) == 0)
- return(TRUE);
- }
-
- return(FALSE);
+ return(user_in_group(sudo_user.pw, def_exempt_group));
}
/*
p = user_tty;
if (def_targetpw)
len = easprintf(timestampfile, "%s/%s/%s:%s", dirparent, user_name,
- p, *user_runas);
+ p, runas_pw->pw_name);
else
len = easprintf(timestampfile, "%s/%s/%s", dirparent, user_name, p);
if (len >= PATH_MAX)
log_error(0, "timestamp path too long: %s", *timestampfile);
} else if (def_targetpw) {
len = easprintf(timestampfile, "%s/%s/%s", dirparent, user_name,
- *user_runas);
+ runas_pw->pw_name);
if (len >= PATH_MAX)
log_error(0, "timestamp path too long: %s", *timestampfile);
} else
int flags;
{
struct stat sb;
+ struct timeval boottime, mtime;
time_t now;
char *dirparent = def_timestampdir;
int status = TS_ERROR; /* assume the worst */
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;
if ((sb.st_mode & 0000777) != 0600)
(void) chmod(timestampfile, 0600);
- status = TS_OLD; /* actually check mtime below */
+ /*
+ * 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) {
* 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 && sb.st_mtime != 0)
+ if (def_timestamp_timeout < 0 && mtime.tv_sec != 0)
status = TS_CURRENT;
else {
- /* XXX - should use timespec here */
now = time(NULL);
if (def_timestamp_timeout &&
- now - sb.st_mtime < 60 * 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 (sb.st_mtime > now + 60 * def_timestamp_timeout * 2) {
+ if (mtime.tv_sec > now + 60 * def_timestamp_timeout * 2) {
+ time_t tv_sec = (time_t)mtime.tv_sec;
log_error(NO_EXIT,
"timestamp too far in the future: %20.20s",
- 4 + ctime(&sb.st_mtime));
+ 4 + ctime(&tv_sec));
if (timestampfile)
(void) unlink(timestampfile);
else
(void) rmdir(timestampdir);
status = TS_MISSING;
- } else
+ } else if (get_boottime(&boottime) && timevalcmp(&mtime, &boottime, <)) {
+ status = TS_OLD;
+ } else {
status = TS_CURRENT;
+ }
}
}
}
+done:
if (timestamp_uid != 0)
set_perms(PERM_ROOT);
return(status);
remove_timestamp(remove)
int remove;
{
- struct timespec ts;
+ struct timeval tv;
char *timestampdir, *timestampfile, *path;
int status;
remove = FALSE;
}
} else {
- timespecclear(&ts);
- if (touch(-1, path, &ts) == -1)
- err(1, "can't reset %s to Epoch", path);
+ timevalclear(&tv);
+ if (touch(-1, path, &tv) == -1 && errno != ENOENT)
+ error(1, "can't reset %s to Epoch", path);
}
}
efree(timestampdir);
efree(timestampfile);
}
+
+/*
+ * Returns TRUE if tty lives on a devpts 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 int
+tty_is_devpts(tty)
+ const char *tty;
+{
+ int retval = FALSE;
+#ifdef __linux__
+ struct statfs sfs;
+
+#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;
+
+ if (statvfs(tty, &sfs) == 0) {
+ if (strcmp(sfs.f_fstr, "devices") == 0)
+ retval = TRUE;
+ }
+#endif /* __linux__ */
+ return retval;
+}
projects / debian / sudo / blobdiff