diff options
author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-01-27 11:14:02 -0500 |
---|---|---|
committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-01-27 11:14:02 -0500 |
commit | 6c02b7b1610f873888af20f291c07730889ff0f9 (patch) | |
tree | 1b33e6642cc81605b8d37c0bda0abff0ba64fa2d /lib/mpi/generic_mpih-rshift.c | |
parent | 7a7546b377bdaa25ac77f33d9433c59f259b9688 (diff) | |
parent | dcd6c92267155e70a94b3927bce681ce74b80d1f (diff) |
Merge commit 'v3.3-rc1' into stable/for-linus-fixes-3.3
* commit 'v3.3-rc1': (9775 commits)
Linux 3.3-rc1
x86, syscall: Need __ARCH_WANT_SYS_IPC for 32 bits
qnx4: don't leak ->BitMap on late failure exits
qnx4: reduce the insane nesting in qnx4_checkroot()
qnx4: di_fname is an array, for crying out loud...
KEYS: Permit key_serial() to be called with a const key pointer
keys: fix user_defined key sparse messages
ima: fix cred sparse warning
uml: fix compile for x86-64
MPILIB: Add a missing ENOMEM check
tpm: fix (ACPI S3) suspend regression
nvme: fix merge error due to change of 'make_request_fn' fn type
xen: using EXPORT_SYMBOL requires including export.h
gpio: tps65910: Use correct offset for gpio initialization
acpi/apei/einj: Add extensions to EINJ from rev 5.0 of acpi spec
intel_idle: Split up and provide per CPU initialization func
ACPI processor: Remove unneeded variable passed by acpi_processor_hotadd_init V2
tg3: Fix single-vector MSI-X code
openvswitch: Fix multipart datapath dumps.
ipv6: fix per device IP snmp counters
...
Diffstat (limited to 'lib/mpi/generic_mpih-rshift.c')
-rw-r--r-- | lib/mpi/generic_mpih-rshift.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/lib/mpi/generic_mpih-rshift.c b/lib/mpi/generic_mpih-rshift.c new file mode 100644 index 00000000000..ffa328818ca --- /dev/null +++ b/lib/mpi/generic_mpih-rshift.c @@ -0,0 +1,63 @@ +/* mpih-rshift.c - MPI helper functions + * 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. + */ + +#include "mpi-internal.h" + +/* Shift U (pointed to by UP and USIZE limbs long) CNT bits to the right + * and store the USIZE least significant limbs of the result at WP. + * The bits shifted out to the right are returned. + * + * Argument constraints: + * 1. 0 < CNT < BITS_PER_MP_LIMB + * 2. If the result is to be written over the input, WP must be <= UP. + */ + +mpi_limb_t +mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned cnt) +{ + mpi_limb_t high_limb, low_limb; + unsigned sh_1, sh_2; + mpi_size_t i; + mpi_limb_t retval; + + sh_1 = cnt; + wp -= 1; + sh_2 = BITS_PER_MPI_LIMB - sh_1; + high_limb = up[0]; + retval = high_limb << sh_2; + low_limb = high_limb; + for (i = 1; i < usize; i++) { + high_limb = up[i]; + wp[i] = (low_limb >> sh_1) | (high_limb << sh_2); + low_limb = high_limb; + } + wp[i] = low_limb >> sh_1; + + return retval; +} |