On Thu, Jul 16, 2020 at 05:37:32PM +0300, Ard Biesheuvel wrote: > On Thu, 16 Jul 2020 at 17:23, Marcelo Henrique Cerri > wrote: > > > > On Thu, Jul 16, 2020 at 04:53:24PM +0300, Ard Biesheuvel wrote: > > > On Thu, 16 Jul 2020 at 16:41, Marcelo Henrique Cerri > > > wrote: > > > > > > > > On Thu, Jul 16, 2020 at 04:09:39PM +0300, Ard Biesheuvel wrote: > > > > > On Thu, 16 Jul 2020 at 15:50, Marcelo Henrique Cerri > > > > > wrote: > > > > > > > > > > > > No. The code is really based on Gnu MP. I used the header from > > > > > > lib/mpi/mpi-pow.c as reference and that's source of the mention to > > > > > > GnuPG that went unnoticed by me. > > > > > > > > > > > > > > > > So where did the file lib/mpi/mpi-sub-ui.c come from? From GnuPG or > > > > > from GnuMP? Did you modify the license statement? Because as proposed, > > > > > this patch clearly is not acceptable from GPL compliance point of > > > > > view. > > > > > > > > Sorry for the confusion. The code is from Gnu MP (not GnuPG). > > > > > > > > Gnu MP is distributed under either LGPLv3 or later or GPLv2 or later > > > > (check their license statement on the aors_ui.h file below). > > > > > > > > For mpi-sub-ui.h I added a SPDX identifier for GPLv2 or later and I > > > > kept the FSF copyright line. > > > > > > > > I also used the header from mpi-powm.c as a reference basically to > > > > inform the code was changed from its original form. > > > > > > > > Here lies my mistake, I didn't notice that part was referring to GnuPG > > > > instead of Gnu MP. > > > > > > > > So mpi-sub-ui.h header was actually intended to be: > > > > > > > > // SPDX-License-Identifier: GPL-2.0-or-later > > > > /* mpi-sub-ui.c - MPI functions > > > > * Copyright 1991, 1993, 1994, 1996, 1999-2002, 2004, 2012, 2013, 2015 > > > > * Free Software Foundation, Inc. > > > > * > > > > * This file is part of Gnu MP. > > > > * > > > > * 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. > > > > */ > > > > > > > > Or maybe instead of "This file is part of Gnu MP.", "This file is > > > > based on Gnu MP" might be more appropriate. > > > > > > > > Do you have any license concerns considering this updated header? > > > > > > > > > > Yes. How can this code be both part of GnuMP *and* be heavily based on > > > it, but with changes? > > > The final mpi-sub-ui.c is not part of Gnu MP, but heavily based on it sounds very accurate to me. > > You haven't answered this question yet. I suppose you just slapped a > different license text on this file, one that already existed in > lib/mpi? Correct. The copyright line I used matches the original copyright from Gnu MP. The "This file is part..." line and the Note is the same from mpi/lib/mpi-powm.c. However I'm proposing the removal of that part in favor of the new header I listed below based on Gnu MP header. > > > > Please avoid making changes to the original header, just add the SPDX > > > header in front, and add a clear justification in the commit log where > > > the file came from (preferably including git url and commit ID), and > > > what you based your assertion on that its license is compatible with > > > GPLv2. > > > > The commit message is stating the origin, but I can add a reference to > > the mercurial repo with its corresponding id. > > > > Yes, please. > > > > > > > Ideally, you would import the file *exactly* as it appears in the > > > upstream in one patch (with the above justification), and apply any > > > necessary changes in a subsequent patch, so it's crystal clear that > > > we are complying with the original license. > > > > I'm not sure that's the ideal approach for this case. The logic is the > > same but since naming convention, macros, data types and etc are > > pretty different everything was basically re-written to fit the > > kernel. Adding the original file and then massively changing will just > > add unnecessary noise. > > > > Do any of these modifications resemble the changes made to the GnuPG > versions of these routines? I haven't looked at the GnuPG code at all. Neither while I was preparing this patch, neither after or before. So I can affirm this patch has no influence of GnuPG code at all. But if you want to be sure I can check that. Please let me know. As I said, the GnuPG reference came from me trying to re-use the header from kernel's lib/mpi/mpi-powm.c file. > > > If you agree I will update the commit message with more details about > > the original source and then just update the comment header in > > mpi-sub-ui.c following closely the original header with minor > > adjustments to explain its origin and to fix some checkpatch warnings. > > > > That is fine, provided that none of our modifications were taken from > the GnuPG version of this file without giving credit. I can assure I haven't used any code from GnuPG at all. > > > > Something like that: > > > > // SPDX-License-Identifier: GPL-2.0-or-later > > /* mpi-sub-ui.c - Subtract an unsigned integer from an MPI. > > * > > * Copyright 1991, 1993, 1994, 1996, 1999-2002, 2004, 2012, 2013, 2015 > > * Free Software Foundation, Inc. > > * > > * This file was based on the GNU MP Library source file: > > * https://gmplib.org/repo/gmp-6.2/file/tip/mpz/aors_ui.h > > * > > * The GNU MP Library is free software; you can redistribute it and/or modify > > * it under the terms of either: > > * > > * * the GNU Lesser General Public License as published by the Free > > * Software Foundation; either version 3 of the License, or (at your > > * option) any later version. > > * > > * or > > * > > * * 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. > > * > > * or both in parallel, as here. > > * > > * The GNU MP Library 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 copies of the GNU General Public License and the > > * GNU Lesser General Public License along with the GNU MP Library. If not, > > * see https://www.gnu.org/licenses/. > > */ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > You can find the original Gnu MP source that I used as reference in > > > > > > the file gmp-6.2.0/mpz/aors_ui.h from: > > > > > > > > > > > > https://gmplib.org/download/gmp/gmp-6.2.0.tar.lz > > > > > > > > > > > > I'm pasting the contents of gmp-6.2.0/mpz/aors_ui.h below for > > > > > > reference. Do you think we should use or adapt the original header > > > > > > instead? > > > > > > > > > > > > That said, assuming the patch set submitted by Tianjia is updated to > > > > > > ensure that mpi_sub_ui() and other functions are returning allocation > > > > > > errors, we could drop this patch in favor of that patch set that is > > > > > > more extensive and also provides an implementation to mpi_sub_ui(). > > > > > > > > > > > > > > > > > > --->8--- > > > > > > /* mpz_add_ui, mpz_sub_ui -- Add or subtract an mpz_t and an unsigned > > > > > > one-word integer. > > > > > > > > > > > > Copyright 1991, 1993, 1994, 1996, 1999-2002, 2004, 2012, 2013, 2015 > > > > > > Free Software Foundation, Inc. > > > > > > > > > > > > > > > > > > Gnu MP license -. > > > > V > > > > > > > > > > > > > > This file is part of the GNU MP Library. > > > > > > > > > > > > The GNU MP Library is free software; you can redistribute it and/or modify > > > > > > it under the terms of either: > > > > > > > > > > > > * the GNU Lesser General Public License as published by the Free > > > > > > Software Foundation; either version 3 of the License, or (at your > > > > > > option) any later version. > > > > > > > > > > > > or > > > > > > > > > > > > * 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. > > > > > > > > > > > > or both in parallel, as here. > > > > > > > > > > > > The GNU MP Library 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 copies of the GNU General Public License and the > > > > > > GNU Lesser General Public License along with the GNU MP Library. If not, > > > > > > see https://www.gnu.org/licenses/. */ > > > > > > > > > > > > #include "gmp-impl.h" > > > > > > > > > > > > > > > > > > #ifdef OPERATION_add_ui > > > > > > #define FUNCTION mpz_add_ui > > > > > > #define FUNCTION2 mpz_add > > > > > > #define VARIATION_CMP >= > > > > > > #define VARIATION_NEG > > > > > > #define VARIATION_UNNEG - > > > > > > #endif > > > > > > > > > > > > #ifdef OPERATION_sub_ui > > > > > > #define FUNCTION mpz_sub_ui > > > > > > #define FUNCTION2 mpz_sub > > > > > > #define VARIATION_CMP < > > > > > > #define VARIATION_NEG - > > > > > > #define VARIATION_UNNEG > > > > > > #endif > > > > > > > > > > > > #ifndef FUNCTION > > > > > > Error, need OPERATION_add_ui or OPERATION_sub_ui > > > > > > #endif > > > > > > > > > > > > > > > > > > void > > > > > > FUNCTION (mpz_ptr w, mpz_srcptr u, unsigned long int vval) > > > > > > { > > > > > > mp_srcptr up; > > > > > > mp_ptr wp; > > > > > > mp_size_t usize, wsize; > > > > > > mp_size_t abs_usize; > > > > > > > > > > > > #if BITS_PER_ULONG > GMP_NUMB_BITS /* avoid warnings about shift amount */ > > > > > > if (vval > GMP_NUMB_MAX) > > > > > > { > > > > > > mpz_t v; > > > > > > mp_limb_t vl[2]; > > > > > > PTR(v) = vl; > > > > > > vl[0] = vval & GMP_NUMB_MASK; > > > > > > vl[1] = vval >> GMP_NUMB_BITS; > > > > > > SIZ(v) = 2; > > > > > > FUNCTION2 (w, u, v); > > > > > > return; > > > > > > } > > > > > > #endif > > > > > > > > > > > > usize = SIZ (u); > > > > > > if (usize == 0) > > > > > > { > > > > > > MPZ_NEWALLOC (w, 1)[0] = vval; > > > > > > SIZ (w) = VARIATION_NEG (vval != 0); > > > > > > return; > > > > > > } > > > > > > > > > > > > abs_usize = ABS (usize); > > > > > > > > > > > > /* If not space for W (and possible carry), increase space. */ > > > > > > wp = MPZ_REALLOC (w, abs_usize + 1); > > > > > > > > > > > > /* These must be after realloc (U may be the same as W). */ > > > > > > up = PTR (u); > > > > > > > > > > > > if (usize VARIATION_CMP 0) > > > > > > { > > > > > > mp_limb_t cy; > > > > > > cy = mpn_add_1 (wp, up, abs_usize, (mp_limb_t) vval); > > > > > > wp[abs_usize] = cy; > > > > > > wsize = VARIATION_NEG (abs_usize + cy); > > > > > > } > > > > > > else > > > > > > { > > > > > > /* The signs are different. Need exact comparison to determine > > > > > > which operand to subtract from which. */ > > > > > > if (abs_usize == 1 && up[0] < vval) > > > > > > { > > > > > > wp[0] = vval - up[0]; > > > > > > wsize = VARIATION_NEG 1; > > > > > > } > > > > > > else > > > > > > { > > > > > > mpn_sub_1 (wp, up, abs_usize, (mp_limb_t) vval); > > > > > > /* Size can decrease with at most one limb. */ > > > > > > wsize = VARIATION_UNNEG (abs_usize - (wp[abs_usize - 1] == 0)); > > > > > > } > > > > > > } > > > > > > > > > > > > SIZ (w) = wsize; > > > > > > } > > > > > > --->*--- > > > > > > > > > > > > > > > > > > > > > > > > On Thu, Jul 16, 2020 at 11:41:17AM +0300, Ard Biesheuvel wrote: > > > > > > > On Thu, 16 Jul 2020 at 10:30, Herbert Xu wrote: > > > > > > > > > > > > > > > > On Sun, Jul 12, 2020 at 06:39:54PM +0200, Stephan Müller wrote: > > > > > > > > > > > > > > > > > > diff --git a/lib/mpi/mpi-sub-ui.c b/lib/mpi/mpi-sub-ui.c > > > > > > > > > new file mode 100644 > > > > > > > > > index 000000000000..fa6b085bac36 > > > > > > > > > --- /dev/null > > > > > > > > > +++ b/lib/mpi/mpi-sub-ui.c > > > > > > > > > @@ -0,0 +1,60 @@ > > > > > > > > > +// SPDX-License-Identifier: GPL-2.0-or-later > > > > > > > > > +/* mpi-sub-ui.c - MPI functions > > > > > > > > > + * Copyright 1991, 1993, 1994, 1996, 1999-2002, 2004, 2012, 2013, 2015 > > > > > > > > > + * Free Software Foundation, Inc. > > > > > > > > > + * > > > > > > > > > + * This file is part of GnuPG. > > > > > > > > > + * > > > > > > > > > + * 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. > > > > > > > > > + */ > > > > > > > > > > > > > > > > Hmm, you said that this code is from GNU MP. But this notice clearly > > > > > > > > says that it's part of GnuPG and is under GPL. Though it doesn't > > > > > > > > clarify what version of GPL it is. Can you please clarify this with > > > > > > > > the author? > > > > > > > > > > > > > > > > > > > > > > GnuPG was relicensed under GPLv3 in ~2007, IIRC, so given the > > > > > > > copyright years and the explicit statements that the file is part of > > > > > > > GnuPG and not under the original LGPL license, there is no way we can > > > > > > > take this code under the kernel's GPLv2 license. > > > > > > > > > > > > -- > > > > > > Regards, > > > > > > Marcelo > > > > > > > > > > > > > > -- > > > > Regards, > > > > Marcelo > > > > > > > > -- > > Regards, > > Marcelo > > -- Regards, Marcelo