summaryrefslogtreecommitdiffstats
path: root/lib/mpi/generic_mpih-add1.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2012-01-10 21:51:23 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-10 21:51:23 -0800
commite7691a1ce341c80ed9504244a36b31c025217391 (patch)
treee9941bb350f64a726130e299c411821da6f41a53 /lib/mpi/generic_mpih-add1.c
parent5cd9599bba428762025db6027764f1c59d0b1e1b (diff)
parent8fcc99549522fc7a0bbaeb5755855ab0d9a59ce8 (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-add1.c')
-rw-r--r--lib/mpi/generic_mpih-add1.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/lib/mpi/generic_mpih-add1.c b/lib/mpi/generic_mpih-add1.c
new file mode 100644
index 00000000000..c94c7dd344b
--- /dev/null
+++ b/lib/mpi/generic_mpih-add1.c
@@ -0,0 +1,61 @@
+/* mpihelp-add_1.c - MPI helper functions
+ * Copyright (C) 1994, 1996, 1997, 1998,
+ * 2000 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"
+#include "longlong.h"
+
+mpi_limb_t
+mpihelp_add_n(mpi_ptr_t res_ptr, mpi_ptr_t s1_ptr,
+ mpi_ptr_t s2_ptr, mpi_size_t size)
+{
+ mpi_limb_t x, y, cy;
+ mpi_size_t j;
+
+ /* The loop counter and index J goes from -SIZE to -1. This way
+ the loop becomes faster. */
+ j = -size;
+
+ /* Offset the base pointers to compensate for the negative indices. */
+ s1_ptr -= j;
+ s2_ptr -= j;
+ res_ptr -= j;
+
+ cy = 0;
+ do {
+ y = s2_ptr[j];
+ x = s1_ptr[j];
+ y += cy; /* add previous carry to one addend */
+ cy = y < cy; /* get out carry from that addition */
+ y += x; /* add other addend */
+ cy += y < x; /* get out carry from that add, combine */
+ res_ptr[j] = y;
+ } while (++j);
+
+ return cy;
+}