ipxe.py 文件源码

def _write_file(filename, data):
    # If the ISO was tampered with such that the destination is a symlink,
    # that could allow a malicious user to write to protected areas of the
    # dom0 filesystem. /HT to comstud for pointing this out.
    #
    # Short-term, checking that the destination is not a symlink should be
    # sufficient.
    #
    # Long-term, we probably want to perform all file manipulations within a
    # chroot jail to be extra safe.
    if os.path.islink(filename):
        raise RuntimeError('SECURITY: Cannot write to symlinked destination')

    logging.debug("Writing to file '%s'" % filename)
    f = open(filename, 'w')
    try:
        f.write(data)
    finally:
        f.close()