void
__libc_init_secure (void)
{
if (__libc_enable_secure_decided == 0)
__libc_enable_secure = (__geteuid () != __getuid ()
|| __getegid () != __getgid ());
}
/* Return any pending signal or wait for one for the given time. */
int
__sigqueue (pid_t pid, int sig, const union sigval val)
{
siginfo_t info;
/* First, clear the siginfo_t structure, so that we don't pass our
stack content to other tasks. */
memset (&info, 0, sizeof (siginfo_t));
/* We must pass the information about the data in a siginfo_t value. */
info.si_signo = sig;
info.si_code = SI_QUEUE;
info.si_pid = __getpid ();
info.si_uid = __getuid ();
info.si_value = val;
return INLINE_SYSCALL (rt_sigqueueinfo, 3, pid, sig, &info);
}
int
faccessat (int fd, const char *file, int mode, int flag)
{
if (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS))
return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
if ((flag == 0 || ((flag & ~AT_EACCESS) == 0 && ! __libc_enable_secure)))
return INLINE_SYSCALL (faccessat, 3, fd, file, mode);
struct stat64 stats;
if (__fxstatat64 (_STAT_VER, fd, file, &stats, flag & AT_SYMLINK_NOFOLLOW))
return -1;
mode &= (X_OK | W_OK | R_OK); /* Clear any bogus bits. */
#if R_OK != S_IROTH || W_OK != S_IWOTH || X_OK != S_IXOTH
# error Oops, portability assumptions incorrect.
#endif
if (mode == F_OK)
return 0; /* The file exists. */
uid_t uid = (flag & AT_EACCESS) ? __geteuid () : __getuid ();
/* The super-user can read and write any file, and execute any file
that anyone can execute. */
if (uid == 0 && ((mode & X_OK) == 0
|| (stats.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))))
return 0;
int granted = (uid == stats.st_uid
? (unsigned int) (stats.st_mode & (mode << 6)) >> 6
: (stats.st_gid == ((flag & AT_EACCESS)
? __getegid () : __getgid ())
|| __group_member (stats.st_gid))
? (unsigned int) (stats.st_mode & (mode << 3)) >> 3
: (stats.st_mode & mode));
if (granted == mode)
return 0;
return INLINE_SYSCALL_ERROR_RETURN_VALUE (EACCES);
}
/* Spawn a new process executing PATH with the attributes describes in *ATTRP.
Before running the process perform the actions described in FILE-ACTIONS. */
int
__spawni (pid_t *pid, const char *file,
const posix_spawn_file_actions_t *file_actions,
const posix_spawnattr_t *attrp, char *const argv[],
char *const envp[], int xflags)
{
pid_t new_pid;
char *path, *p, *name;
size_t len;
size_t pathlen;
/* Do this once. */
short int flags = attrp == NULL ? 0 : attrp->__flags;
/* Generate the new process. */
if ((flags & POSIX_SPAWN_USEVFORK) != 0
/* If no major work is done, allow using vfork. Note that we
might perform the path searching. But this would be done by
a call to execvp(), too, and such a call must be OK according
to POSIX. */
|| ((flags & (POSIX_SPAWN_SETSIGMASK | POSIX_SPAWN_SETSIGDEF
| POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER
| POSIX_SPAWN_SETPGROUP | POSIX_SPAWN_RESETIDS)) == 0
&& file_actions == NULL))
new_pid = __vfork ();
else
new_pid = __fork ();
if (new_pid != 0)
{
if (new_pid < 0)
return errno;
/* The call was successful. Store the PID if necessary. */
if (pid != NULL)
*pid = new_pid;
return 0;
}
/* Set signal mask. */
if ((flags & POSIX_SPAWN_SETSIGMASK) != 0
&& __sigprocmask (SIG_SETMASK, &attrp->__ss, NULL) != 0)
_exit (SPAWN_ERROR);
/* Set signal default action. */
if ((flags & POSIX_SPAWN_SETSIGDEF) != 0)
{
/* We have to iterate over all signals. This could possibly be
done better but it requires system specific solutions since
the sigset_t data type can be very different on different
architectures. */
int sig;
struct sigaction sa;
memset (&sa, '\0', sizeof (sa));
sa.sa_handler = SIG_DFL;
for (sig = 1; sig <= _NSIG; ++sig)
if (__sigismember (&attrp->__sd, sig) != 0
&& __sigaction (sig, &sa, NULL) != 0)
_exit (SPAWN_ERROR);
}
#ifdef _POSIX_PRIORITY_SCHEDULING
/* Set the scheduling algorithm and parameters. */
if ((flags & (POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER))
== POSIX_SPAWN_SETSCHEDPARAM)
{
if (__sched_setparam (0, &attrp->__sp) == -1)
_exit (SPAWN_ERROR);
}
else if ((flags & POSIX_SPAWN_SETSCHEDULER) != 0)
{
if (__sched_setscheduler (0, attrp->__policy, &attrp->__sp) == -1)
_exit (SPAWN_ERROR);
}
#endif
/* Set the process group ID. */
if ((flags & POSIX_SPAWN_SETPGROUP) != 0
&& __setpgid (0, attrp->__pgrp) != 0)
_exit (SPAWN_ERROR);
/* Set the effective user and group IDs. */
if ((flags & POSIX_SPAWN_RESETIDS) != 0
&& (local_seteuid (__getuid ()) != 0
|| local_setegid (__getgid ()) != 0))
_exit (SPAWN_ERROR);
/* Execute the file actions. */
if (file_actions != NULL)
{
int cnt;
struct rlimit64 fdlimit;
bool have_fdlimit = false;
for (cnt = 0; cnt < file_actions->__used; ++cnt)
{
struct __spawn_action *action = &file_actions->__actions[cnt];
switch (action->tag)
{
case spawn_do_close:
if (close_not_cancel (action->action.close_action.fd) != 0)
{
if (! have_fdlimit)
{
getrlimit64 (RLIMIT_NOFILE, &fdlimit);
have_fdlimit = true;
}
/* Only signal errors for file descriptors out of range. */
if (action->action.close_action.fd < 0
|| action->action.close_action.fd >= fdlimit.rlim_cur)
/* Signal the error. */
_exit (SPAWN_ERROR);
}
break;
case spawn_do_open:
{
int new_fd = open_not_cancel (action->action.open_action.path,
action->action.open_action.oflag
| O_LARGEFILE,
action->action.open_action.mode);
if (new_fd == -1)
/* The `open' call failed. */
_exit (SPAWN_ERROR);
/* Make sure the desired file descriptor is used. */
if (new_fd != action->action.open_action.fd)
{
if (__dup2 (new_fd, action->action.open_action.fd)
!= action->action.open_action.fd)
/* The `dup2' call failed. */
_exit (SPAWN_ERROR);
if (close_not_cancel (new_fd) != 0)
/* The `close' call failed. */
_exit (SPAWN_ERROR);
}
}
break;
case spawn_do_dup2:
if (__dup2 (action->action.dup2_action.fd,
action->action.dup2_action.newfd)
!= action->action.dup2_action.newfd)
/* The `dup2' call failed. */
_exit (SPAWN_ERROR);
break;
}
}
}
if ((xflags & SPAWN_XFLAGS_USE_PATH) == 0 || strchr (file, '/') != NULL)
{
/* The FILE parameter is actually a path. */
__execve (file, argv, envp);
maybe_script_execute (file, argv, envp, xflags);
/* Oh, oh. `execve' returns. This is bad. */
_exit (SPAWN_ERROR);
}
/* We have to search for FILE on the path. */
path = getenv ("PATH");
if (path == NULL)
{
/* There is no `PATH' in the environment.
The default search path is the current directory
followed by the path `confstr' returns for `_CS_PATH'. */
len = confstr (_CS_PATH, (char *) NULL, 0);
path = (char *) __alloca (1 + len);
path[0] = ':';
(void) confstr (_CS_PATH, path + 1, len);
}
len = strlen (file) + 1;
pathlen = strlen (path);
name = __alloca (pathlen + len + 1);
/* Copy the file name at the top. */
name = (char *) memcpy (name + pathlen + 1, file, len);
/* And add the slash. */
*--name = '/';
p = path;
do
{
char *startp;
path = p;
p = __strchrnul (path, ':');
if (p == path)
/* Two adjacent colons, or a colon at the beginning or the end
of `PATH' means to search the current directory. */
startp = name + 1;
else
startp = (char *) memcpy (name - (p - path), path, p - path);
/* Try to execute this name. If it works, execv will not return. */
__execve (startp, argv, envp);
maybe_script_execute (startp, argv, envp, xflags);
switch (errno)
{
case EACCES:
case ENOENT:
case ESTALE:
case ENOTDIR:
/* Those errors indicate the file is missing or not executable
by us, in which case we want to just try the next path
directory. */
break;
default:
/* Some other error means we found an executable file, but
something went wrong executing it; return the error to our
caller. */
_exit (SPAWN_ERROR);
}
}
while (*p++ != '\0');
/* Return with an error. */
_exit (SPAWN_ERROR);
}
/* Change the ownership and access permission of the slave pseudo
terminal associated with the master pseudo terminal specified
by FD. */
int
grantpt (int fd)
{
int retval = -1;
#ifdef PATH_MAX
char _buf[PATH_MAX];
#else
char _buf[512];
#endif
char *buf = _buf;
struct stat64 st;
if (__glibc_unlikely (pts_name (fd, &buf, sizeof (_buf), &st)))
{
int save_errno = errno;
/* Check, if the file descriptor is valid. pts_name returns the
wrong errno number, so we cannot use that. */
if (__libc_fcntl (fd, F_GETFD) == -1 && errno == EBADF)
return -1;
/* If the filedescriptor is no TTY, grantpt has to set errno
to EINVAL. */
if (save_errno == ENOTTY)
__set_errno (EINVAL);
else
__set_errno (save_errno);
return -1;
}
/* Make sure that we own the device. */
uid_t uid = __getuid ();
if (st.st_uid != uid)
{
if (__chown (buf, uid, st.st_gid) < 0)
goto helper;
}
static int tty_gid = -1;
if (__glibc_unlikely (tty_gid == -1))
{
char *grtmpbuf;
struct group grbuf;
size_t grbuflen = __sysconf (_SC_GETGR_R_SIZE_MAX);
struct group *p;
/* Get the group ID of the special `tty' group. */
if (grbuflen == (size_t) -1L)
/* `sysconf' does not support _SC_GETGR_R_SIZE_MAX.
Try a moderate value. */
grbuflen = 1024;
grtmpbuf = (char *) __alloca (grbuflen);
__getgrnam_r (TTY_GROUP, &grbuf, grtmpbuf, grbuflen, &p);
if (p != NULL)
tty_gid = p->gr_gid;
}
gid_t gid = tty_gid == -1 ? __getgid () : tty_gid;
/* Make sure the group of the device is that special group. */
if (st.st_gid != gid)
{
if (__chown (buf, uid, gid) < 0)
goto helper;
}
/* Make sure the permission mode is set to readable and writable by
the owner, and writable by the group. */
if ((st.st_mode & ACCESSPERMS) != (S_IRUSR|S_IWUSR|S_IWGRP))
{
if (__chmod (buf, S_IRUSR|S_IWUSR|S_IWGRP) < 0)
goto helper;
}
retval = 0;
goto cleanup;
/* We have to use the helper program if it is available. */
helper:;
#ifdef HAVE_PT_CHOWN
pid_t pid = __fork ();
if (pid == -1)
goto cleanup;
else if (pid == 0)
{
/* Disable core dumps. */
struct rlimit rl = { 0, 0 };
__setrlimit (RLIMIT_CORE, &rl);
/* We pass the master pseudo terminal as file descriptor PTY_FILENO. */
if (fd != PTY_FILENO)
if (__dup2 (fd, PTY_FILENO) < 0)
_exit (FAIL_EBADF);
# ifdef CLOSE_ALL_FDS
CLOSE_ALL_FDS ();
# endif
execle (_PATH_PT_CHOWN, basename (_PATH_PT_CHOWN), NULL, NULL);
_exit (FAIL_EXEC);
}
else
{
int w;
if (__waitpid (pid, &w, 0) == -1)
goto cleanup;
if (!WIFEXITED (w))
__set_errno (ENOEXEC);
else
switch (WEXITSTATUS (w))
{
case 0:
retval = 0;
break;
case FAIL_EBADF:
__set_errno (EBADF);
break;
case FAIL_EINVAL:
__set_errno (EINVAL);
break;
case FAIL_EACCES:
__set_errno (EACCES);
break;
case FAIL_EXEC:
__set_errno (ENOEXEC);
break;
case FAIL_ENOMEM:
__set_errno (ENOMEM);
break;
default:
assert(! "getpt: internal error: invalid exit code from pt_chown");
}
}
#endif
cleanup:
if (buf != _buf)
free (buf);
return retval;
}
/* Function used in the clone call to setup the signals mask, posix_spawn
attributes, and file actions. It run on its own stack (provided by the
posix_spawn call). */
static int
__spawni_child (void *arguments)
{
struct posix_spawn_args *args = arguments;
const posix_spawnattr_t *restrict attr = args->attr;
const posix_spawn_file_actions_t *file_actions = args->fa;
int p = args->pipe[1];
int ret;
close_not_cancel (args->pipe[0]);
/* The child must ensure that no signal handler are enabled because it shared
memory with parent, so the signal disposition must be either SIG_DFL or
SIG_IGN. It does by iterating over all signals and although it could
possibly be more optimized (by tracking which signal potentially have a
signal handler), it might requires system specific solutions (since the
sigset_t data type can be very different on different architectures). */
struct sigaction sa;
memset (&sa, '\0', sizeof (sa));
sigset_t hset;
__sigprocmask (SIG_BLOCK, 0, &hset);
for (int sig = 1; sig < _NSIG; ++sig)
{
if ((attr->__flags & POSIX_SPAWN_SETSIGDEF)
&& sigismember (&attr->__sd, sig))
{
sa.sa_handler = SIG_DFL;
}
else if (sigismember (&hset, sig))
{
if (__nptl_is_internal_signal (sig))
sa.sa_handler = SIG_IGN;
else
{
__libc_sigaction (sig, 0, &sa);
if (sa.sa_handler == SIG_IGN)
continue;
sa.sa_handler = SIG_DFL;
}
}
else
continue;
__libc_sigaction (sig, &sa, 0);
}
#ifdef _POSIX_PRIORITY_SCHEDULING
/* Set the scheduling algorithm and parameters. */
if ((attr->__flags & (POSIX_SPAWN_SETSCHEDPARAM | POSIX_SPAWN_SETSCHEDULER))
== POSIX_SPAWN_SETSCHEDPARAM)
{
if ((ret = __sched_setparam (0, &attr->__sp)) == -1)
goto fail;
}
else if ((attr->__flags & POSIX_SPAWN_SETSCHEDULER) != 0)
{
if ((ret = __sched_setscheduler (0, attr->__policy, &attr->__sp)) == -1)
goto fail;
}
#endif
/* Set the process group ID. */
if ((attr->__flags & POSIX_SPAWN_SETPGROUP) != 0
&& (ret = __setpgid (0, attr->__pgrp)) != 0)
goto fail;
/* Set the effective user and group IDs. */
if ((attr->__flags & POSIX_SPAWN_RESETIDS) != 0
&& ((ret = local_seteuid (__getuid ())) != 0
|| (ret = local_setegid (__getgid ())) != 0))
goto fail;
/* Execute the file actions. */
if (file_actions != 0)
{
int cnt;
struct rlimit64 fdlimit;
bool have_fdlimit = false;
for (cnt = 0; cnt < file_actions->__used; ++cnt)
{
struct __spawn_action *action = &file_actions->__actions[cnt];
/* Dup the pipe fd onto an unoccupied one to avoid any file
operation to clobber it. */
if ((action->action.close_action.fd == p)
|| (action->action.open_action.fd == p)
|| (action->action.dup2_action.fd == p))
{
if ((ret = __dup (p)) < 0)
goto fail;
p = ret;
}
switch (action->tag)
{
case spawn_do_close:
if ((ret =
close_not_cancel (action->action.close_action.fd)) != 0)
{
if (!have_fdlimit)
{
__getrlimit64 (RLIMIT_NOFILE, &fdlimit);
have_fdlimit = true;
}
/* Signal errors only for file descriptors out of range. */
if (action->action.close_action.fd < 0
|| action->action.close_action.fd >= fdlimit.rlim_cur)
goto fail;
}
break;
case spawn_do_open:
{
ret = open_not_cancel (action->action.open_action.path,
action->action.
open_action.oflag | O_LARGEFILE,
action->action.open_action.mode);
if (ret == -1)
goto fail;
int new_fd = ret;
/* Make sure the desired file descriptor is used. */
if (ret != action->action.open_action.fd)
{
if ((ret = __dup2 (new_fd, action->action.open_action.fd))
!= action->action.open_action.fd)
goto fail;
if ((ret = close_not_cancel (new_fd)) != 0)
goto fail;
}
}
break;
case spawn_do_dup2:
if ((ret = __dup2 (action->action.dup2_action.fd,
action->action.dup2_action.newfd))
!= action->action.dup2_action.newfd)
goto fail;
break;
}
}
}
/* Set the initial signal mask of the child if POSIX_SPAWN_SETSIGMASK
is set, otherwise restore the previous one. */
__sigprocmask (SIG_SETMASK, (attr->__flags & POSIX_SPAWN_SETSIGMASK)
? &attr->__ss : &args->oldmask, 0);
args->exec (args->file, args->argv, args->envp);
/* This is compatibility function required to enable posix_spawn run
script without shebang definition for older posix_spawn versions
(2.15). */
maybe_script_execute (args);
ret = -errno;
fail:
/* Since sizeof errno < PIPE_BUF, the write is atomic. */
ret = -ret;
if (ret)
while (write_not_cancel (p, &ret, sizeof ret) < 0)
continue;
exit (SPAWN_ERROR);
}
static int
internal_function
key_call_keyenvoy (u_long proc, xdrproc_t xdr_arg, char *arg,
xdrproc_t xdr_rslt, char *rslt)
{
XDR xdrargs;
XDR xdrrslt;
FILE *fargs;
FILE *frslt;
sigset_t oldmask, mask;
union wait status;
int pid;
int success;
uid_t ruid;
uid_t euid;
static const char MESSENGER[] = "/usr/etc/keyenvoy";
success = 1;
sigemptyset (&mask);
sigaddset (&mask, SIGCHLD);
__sigprocmask (SIG_BLOCK, &mask, &oldmask);
/*
* We are going to exec a set-uid program which makes our effective uid
* zero, and authenticates us with our real uid. We need to make the
* effective uid be the real uid for the setuid program, and
* the real uid be the effective uid so that we can change things back.
*/
euid = __geteuid ();
ruid = __getuid ();
__setreuid (euid, ruid);
pid = _openchild (MESSENGER, &fargs, &frslt);
__setreuid (ruid, euid);
if (pid < 0)
{
debug ("open_streams");
__sigprocmask (SIG_SETMASK, &oldmask, NULL);
return (0);
}
xdrstdio_create (&xdrargs, fargs, XDR_ENCODE);
xdrstdio_create (&xdrrslt, frslt, XDR_DECODE);
if (!INTUSE(xdr_u_long) (&xdrargs, &proc) || !(*xdr_arg) (&xdrargs, arg))
{
debug ("xdr args");
success = 0;
}
fclose (fargs);
if (success && !(*xdr_rslt) (&xdrrslt, rslt))
{
debug ("xdr rslt");
success = 0;
}
fclose(frslt);
wait_again:
if (__wait4 (pid, &status, 0, NULL) < 0)
{
if (errno == EINTR)
goto wait_again;
debug ("wait4");
if (errno == ECHILD || errno == ESRCH)
perror ("wait");
else
success = 0;
}
else
if (status.w_retcode)
{
debug ("wait4 1");
success = 0;
}
__sigprocmask (SIG_SETMASK, &oldmask, NULL);
return success;
}
init_secure (void)
{
__libc_enable_secure = (__geteuid () != __getuid () ||
__getegid () != __getgid ());
}
