Re: [PATCH v2 3/5] crypto: Add RSA support

[Jan Beulich <jbeulich@xxxxxxxx>]

On 15.05.2025 11:38, Ross Lagerwall wrote:
> --- a/xen/common/Makefile
> +++ b/xen/common/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o livepatch_elf.o
>  obj-$(CONFIG_LLC_COLORING) += llc-coloring.o
>  obj-$(CONFIG_VM_EVENT) += mem_access.o
>  obj-y += memory.o
> +obj-$(CONFIG_PAYLOAD_VERIFY) += mpi.o

This being odd and non-scalable, I now think the file would better move to
lib/. It _is_ library code, after all. Then it can be included in lib-y
(thus always being built, i.e. reducing the risk of accidental build
breakages), but will be included in the final image only when needed.

> --- /dev/null
> +++ b/xen/include/xen/mpi.h
> @@ -0,0 +1,68 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/* mpi.h  -  Multi Precision Integers
> + *        Copyright (C) 1994, 1996, 1998, 1999,
> + *                    2000, 2001 Free Software Foundation, Inc.
> + *
> + * This file is part of GNUPG.
> + *
> + * GNUPG is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * GNUPG is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
> + *
> + * Note: This code is heavily based on the GNU MP Library.
> + *         Actually it's the same code with only minor changes in the
> + *         way the data is stored; this is to support the abstraction
> + *         of an optional secure memory allocation which may be used
> + *         to avoid revealing of sensitive data due to paging etc.
> + *         The GNU MP Library itself is published under the LGPL;
> + *         however I decided to publish this code under the plain GPL.
> + */
> +
> +#ifndef XEN__MPI_H
> +#define XEN__MPI_H

With the recent change to header guard naming, the double underscore here
(and in rsa.h) wants to shrink back to a single one.

Jan