dc8f923eae
The Reed-Solomon library is based on code from Phil Karn who granted
permission to import it into the kernel under the GPL V2.
See commit 15b5423757a7 ("Shared Reed-Solomon ECC library") in the history
git tree at: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
...
The encoder/decoder code is lifted from the GPL'd userspace RS-library
written by Phil Karn. I modified/wrapped it to provide the different
functions which we need in the MTD/NAND code.
...
Signed-Off-By: Thomas Gleixner <tglx@linutronix.de>
Signed-Off-By: David Woodhouse <dwmw2@infradead.org>
"No objections at all. Just keep the authorship notices." -- Phil Karn
Add the proper SPDX identifiers according to
Documentation/process/license-rules.rst.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Andrew Morton <akpm@linuxfoundation.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alasdair Kergon <agk@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
47 lines
1.1 KiB
C
47 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Generic Reed Solomon encoder / decoder library
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*
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* Copyright 2002, Phil Karn, KA9Q
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* May be used under the terms of the GNU General Public License (GPL)
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*
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* Adaption to the kernel by Thomas Gleixner (tglx@linutronix.de)
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*
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* Generic data width independent code which is included by the wrappers.
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*/
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{
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int i, j, pad;
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int nn = rs->nn;
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int nroots = rs->nroots;
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uint16_t *alpha_to = rs->alpha_to;
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uint16_t *index_of = rs->index_of;
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uint16_t *genpoly = rs->genpoly;
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uint16_t fb;
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uint16_t msk = (uint16_t) rs->nn;
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/* Check length parameter for validity */
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pad = nn - nroots - len;
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if (pad < 0 || pad >= nn)
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return -ERANGE;
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for (i = 0; i < len; i++) {
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fb = index_of[((((uint16_t) data[i])^invmsk) & msk) ^ par[0]];
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/* feedback term is non-zero */
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if (fb != nn) {
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for (j = 1; j < nroots; j++) {
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par[j] ^= alpha_to[rs_modnn(rs, fb +
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genpoly[nroots - j])];
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}
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}
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/* Shift */
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memmove(&par[0], &par[1], sizeof(uint16_t) * (nroots - 1));
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if (fb != nn) {
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par[nroots - 1] = alpha_to[rs_modnn(rs,
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fb + genpoly[0])];
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} else {
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par[nroots - 1] = 0;
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}
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}
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return 0;
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}
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