static void check_access(
rtems_filesystem_eval_path_context_t *ctx,
int eval_flags
)
{
const rtems_filesystem_location_info_t *currentloc = &ctx->currentloc;
const rtems_filesystem_mount_table_entry_t *mt_entry = currentloc->mt_entry;
if ((eval_flags & RTEMS_FS_PERMS_WRITE) == 0 || mt_entry->writeable) {
struct stat st;
int rv;
st.st_mode = 0;
st.st_uid = 0;
st.st_gid = 0;
rv = (*currentloc->handlers->fstat_h)(currentloc, &st);
if (rv == 0) {
bool access_ok = rtems_filesystem_check_access(
eval_flags,
st.st_mode,
st.st_uid,
st.st_gid
);
if (!access_ok) {
rtems_filesystem_eval_path_error(ctx, EACCES);
}
} else {
rtems_filesystem_eval_path_error(ctx, 0);
}
} else {
rtems_filesystem_eval_path_error(ctx, EROFS);
}
}
static inline bool shm_access_ok( POSIX_Shm_Control *shm, int oflag )
{
int flags;
if ( oflag & O_RDONLY ) {
flags = RTEMS_FS_PERMS_READ;
} else {
flags = RTEMS_FS_PERMS_WRITE;
}
return rtems_filesystem_check_access( flags, shm->mode, shm->uid, shm->gid );
}
bool rtems_filesystem_eval_path_check_access(
rtems_filesystem_eval_path_context_t *ctx,
int eval_flags,
mode_t node_mode,
uid_t node_uid,
gid_t node_gid
)
{
bool access_ok = rtems_filesystem_check_access(
eval_flags,
node_mode,
node_uid,
node_gid
);
if (!access_ok) {
rtems_filesystem_eval_path_error(ctx, EACCES);
}
return access_ok;
}
int fchdir( int fd )
{
int rv = 0;
rtems_libio_t *iop;
struct stat st;
rtems_filesystem_location_info_t loc;
st.st_mode = 0;
st.st_uid = 0;
st.st_gid = 0;
rtems_libio_check_fd( fd );
iop = rtems_libio_iop( fd );
rtems_libio_check_is_open( iop );
rtems_filesystem_instance_lock( &iop->pathinfo );
rv = (*iop->pathinfo.handlers->fstat_h)( &iop->pathinfo, &st );
if ( rv == 0 ) {
bool access_ok = rtems_filesystem_check_access(
RTEMS_FS_PERMS_EXEC,
st.st_mode,
st.st_uid,
st.st_gid
);
if ( access_ok ) {
rtems_filesystem_location_clone( &loc, &iop->pathinfo );
} else {
errno = EACCES;
rv = -1;
}
}
rtems_filesystem_instance_unlock( &iop->pathinfo );
if ( rv == 0 ) {
rv = rtems_filesystem_chdir( &loc );
}
return rv;
}