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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 10:40:14 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-03 10:40:14 -0700 |
| commit | ab5c60b79ab6cc50b39bbb21b2f9fb55af900b84 (patch) | |
| tree | 71fa895fbf01e3b88f26cf257d9105f9d286b631 /lib/mpi/mpi-sub-ui.c | |
| parent | 5577416c39652d395a6045677f4f598564aba1cf (diff) | |
| parent | 3cbfe80737c18ac6e635421ab676716a393d3074 (diff) | |
| download | lwn-ab5c60b79ab6cc50b39bbb21b2f9fb55af900b84.tar.gz lwn-ab5c60b79ab6cc50b39bbb21b2f9fb55af900b84.zip | |
Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
"API:
- Add support for allocating transforms on a specific NUMA Node
- Introduce the flag CRYPTO_ALG_ALLOCATES_MEMORY for storage users
Algorithms:
- Drop PMULL based ghash on arm64
- Fixes for building with clang on x86
- Add sha256 helper that does the digest in one go
- Add SP800-56A rev 3 validation checks to dh
Drivers:
- Permit users to specify NUMA node in hisilicon/zip
- Add support for i.MX6 in imx-rngc
- Add sa2ul crypto driver
- Add BA431 hwrng driver
- Add Ingenic JZ4780 and X1000 hwrng driver
- Spread IRQ affinity in inside-secure and marvell/cesa"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (157 commits)
crypto: sa2ul - Fix inconsistent IS_ERR and PTR_ERR
hwrng: core - remove redundant initialization of variable ret
crypto: x86/curve25519 - Remove unused carry variables
crypto: ingenic - Add hardware RNG for Ingenic JZ4780 and X1000
dt-bindings: RNG: Add Ingenic RNG bindings.
crypto: caam/qi2 - add module alias
crypto: caam - add more RNG hw error codes
crypto: caam/jr - remove incorrect reference to caam_jr_register()
crypto: caam - silence .setkey in case of bad key length
crypto: caam/qi2 - create ahash shared descriptors only once
crypto: caam/qi2 - fix error reporting for caam_hash_alloc
crypto: caam - remove deadcode on 32-bit platforms
crypto: ccp - use generic power management
crypto: xts - Replace memcpy() invocation with simple assignment
crypto: marvell/cesa - irq balance
crypto: inside-secure - irq balance
crypto: ecc - SP800-56A rev 3 local public key validation
crypto: dh - SP800-56A rev 3 local public key validation
crypto: dh - check validity of Z before export
lib/mpi: Add mpi_sub_ui()
...
Diffstat (limited to 'lib/mpi/mpi-sub-ui.c')
| -rw-r--r-- | lib/mpi/mpi-sub-ui.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/lib/mpi/mpi-sub-ui.c b/lib/mpi/mpi-sub-ui.c new file mode 100644 index 000000000000..b41b082b5f3e --- /dev/null +++ b/lib/mpi/mpi-sub-ui.c @@ -0,0 +1,78 @@ +// 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/510b83519d1c/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/. + */ + +#include "mpi-internal.h" + +int mpi_sub_ui(MPI w, MPI u, unsigned long vval) +{ + if (u->nlimbs == 0) { + if (mpi_resize(w, 1) < 0) + return -ENOMEM; + w->d[0] = vval; + w->nlimbs = (vval != 0); + w->sign = (vval != 0); + return 0; + } + + /* If not space for W (and possible carry), increase space. */ + if (mpi_resize(w, u->nlimbs + 1)) + return -ENOMEM; + + if (u->sign) { + mpi_limb_t cy; + + cy = mpihelp_add_1(w->d, u->d, u->nlimbs, (mpi_limb_t) vval); + w->d[u->nlimbs] = cy; + w->nlimbs = u->nlimbs + cy; + w->sign = 1; + } else { + /* The signs are different. Need exact comparison to determine + * which operand to subtract from which. + */ + if (u->nlimbs == 1 && u->d[0] < vval) { + w->d[0] = vval - u->d[0]; + w->nlimbs = 1; + w->sign = 1; + } else { + mpihelp_sub_1(w->d, u->d, u->nlimbs, (mpi_limb_t) vval); + /* Size can decrease with at most one limb. */ + w->nlimbs = (u->nlimbs - (w->d[u->nlimbs - 1] == 0)); + w->sign = 0; + } + } + + mpi_normalize(w); + return 0; +} +EXPORT_SYMBOL_GPL(mpi_sub_ui); |