diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-11 00:51:23 -0500 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-11 00:51:23 -0500 |
commit | e7691a1ce341c80ed9504244a36b31c025217391 (patch) | |
tree | e9941bb350f64a726130e299c411821da6f41a53 /lib/mpi/generic_mpih-rshift.c | |
parent | 5cd9599bba428762025db6027764f1c59d0b1e1b (diff) | |
parent | 8fcc99549522fc7a0bbaeb5755855ab0d9a59ce8 (diff) |
Merge branch 'for-linus' of git://selinuxproject.org/~jmorris/linux-security
* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security: (32 commits)
ima: fix invalid memory reference
ima: free duplicate measurement memory
security: update security_file_mmap() docs
selinux: Casting (void *) value returned by kmalloc is useless
apparmor: fix module parameter handling
Security: tomoyo: add .gitignore file
tomoyo: add missing rcu_dereference()
apparmor: add missing rcu_dereference()
evm: prevent racing during tfm allocation
evm: key must be set once during initialization
mpi/mpi-mpow: NULL dereference on allocation failure
digsig: build dependency fix
KEYS: Give key types their own lockdep class for key->sem
TPM: fix transmit_cmd error logic
TPM: NSC and TIS drivers X86 dependency fix
TPM: Export wait_for_stat for other vendor specific drivers
TPM: Use vendor specific function for status probe
tpm_tis: add delay after aborting command
tpm_tis: Check return code from getting timeouts/durations
tpm: Introduce function to poll for result of self test
...
Fix up trivial conflict in lib/Makefile due to addition of CONFIG_MPI
and SIGSIG next to CONFIG_DQL addition.
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 000000000000..ffa328818ca6 --- /dev/null +++ b/lib/mpi/generic_mpih-rshift.c | |||
@@ -0,0 +1,63 @@ | |||
1 | /* mpih-rshift.c - MPI helper functions | ||
2 | * Copyright (C) 1994, 1996, 1998, 1999, | ||
3 | * 2000, 2001 Free Software Foundation, Inc. | ||
4 | * | ||
5 | * This file is part of GNUPG | ||
6 | * | ||
7 | * GNUPG is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License as published by | ||
9 | * the Free Software Foundation; either version 2 of the License, or | ||
10 | * (at your option) any later version. | ||
11 | * | ||
12 | * GNUPG is distributed in the hope that it will be useful, | ||
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
15 | * GNU General Public License for more details. | ||
16 | * | ||
17 | * You should have received a copy of the GNU General Public License | ||
18 | * along with this program; if not, write to the Free Software | ||
19 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA | ||
20 | * | ||
21 | * Note: This code is heavily based on the GNU MP Library. | ||
22 | * Actually it's the same code with only minor changes in the | ||
23 | * way the data is stored; this is to support the abstraction | ||
24 | * of an optional secure memory allocation which may be used | ||
25 | * to avoid revealing of sensitive data due to paging etc. | ||
26 | * The GNU MP Library itself is published under the LGPL; | ||
27 | * however I decided to publish this code under the plain GPL. | ||
28 | */ | ||
29 | |||
30 | #include "mpi-internal.h" | ||
31 | |||
32 | /* Shift U (pointed to by UP and USIZE limbs long) CNT bits to the right | ||
33 | * and store the USIZE least significant limbs of the result at WP. | ||
34 | * The bits shifted out to the right are returned. | ||
35 | * | ||
36 | * Argument constraints: | ||
37 | * 1. 0 < CNT < BITS_PER_MP_LIMB | ||
38 | * 2. If the result is to be written over the input, WP must be <= UP. | ||
39 | */ | ||
40 | |||
41 | mpi_limb_t | ||
42 | mpihelp_rshift(mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize, unsigned cnt) | ||
43 | { | ||
44 | mpi_limb_t high_limb, low_limb; | ||
45 | unsigned sh_1, sh_2; | ||
46 | mpi_size_t i; | ||
47 | mpi_limb_t retval; | ||
48 | |||
49 | sh_1 = cnt; | ||
50 | wp -= 1; | ||
51 | sh_2 = BITS_PER_MPI_LIMB - sh_1; | ||
52 | high_limb = up[0]; | ||
53 | retval = high_limb << sh_2; | ||
54 | low_limb = high_limb; | ||
55 | for (i = 1; i < usize; i++) { | ||
56 | high_limb = up[i]; | ||
57 | wp[i] = (low_limb >> sh_1) | (high_limb << sh_2); | ||
58 | low_limb = high_limb; | ||
59 | } | ||
60 | wp[i] = low_limb >> sh_1; | ||
61 | |||
62 | return retval; | ||
63 | } | ||