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authorMatt Johnston <matt@ucc.asn.au>2007-02-22 14:53:49 +0000
committerMatt Johnston <matt@ucc.asn.au>2007-02-22 14:53:49 +0000
commitb01a74a9d757ce2b83465214bde1fa07d3e2d3ea (patch)
tree092cac6797947f7b23fcdcc2c081b19c390c5bc4 /libtomcrypt/src/encauth/gcm/gcm_mult_h.c
parent66643fa5c723da2dc781c5eeae2e008c280a7b1c (diff)
parent7f12251fbb2acefac04e13a7c6a95ca4dd4b5578 (diff)
merge of 'a9b0496634cdd25647b65e585cc3240f3fa699ee'
and 'c22be8b8f570b48e9662dac32c7b3e7148a42206' --HG-- extra : convert_revision : 066f6aef2791d54b9ec6a0c3033fd28fa946251f
Diffstat (limited to 'libtomcrypt/src/encauth/gcm/gcm_mult_h.c')
-rw-r--r--libtomcrypt/src/encauth/gcm/gcm_mult_h.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/libtomcrypt/src/encauth/gcm/gcm_mult_h.c b/libtomcrypt/src/encauth/gcm/gcm_mult_h.c
new file mode 100644
index 0000000..8391e00
--- /dev/null
+++ b/libtomcrypt/src/encauth/gcm/gcm_mult_h.c
@@ -0,0 +1,58 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
+ */
+
+/**
+ @file gcm_mult_h.c
+ GCM implementation, do the GF mult, by Tom St Denis
+*/
+#include "tomcrypt.h"
+
+#if defined(GCM_MODE)
+/**
+ GCM multiply by H
+ @param gcm The GCM state which holds the H value
+ @param I The value to multiply H by
+ */
+void gcm_mult_h(gcm_state *gcm, unsigned char *I)
+{
+ unsigned char T[16];
+#ifdef GCM_TABLES
+ int x, y;
+#ifdef GCM_TABLES_SSE2
+ asm("movdqa (%0),%%xmm0"::"r"(&gcm->PC[0][I[0]][0]));
+ for (x = 1; x < 16; x++) {
+ asm("pxor (%0),%%xmm0"::"r"(&gcm->PC[x][I[x]][0]));
+ }
+ asm("movdqa %%xmm0,(%0)"::"r"(&T));
+#else
+ XMEMCPY(T, &gcm->PC[0][I[0]][0], 16);
+ for (x = 1; x < 16; x++) {
+#ifdef LTC_FAST
+ for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) {
+ *((LTC_FAST_TYPE *)(T + y)) ^= *((LTC_FAST_TYPE *)(&gcm->PC[x][I[x]][y]));
+ }
+#else
+ for (y = 0; y < 16; y++) {
+ T[y] ^= gcm->PC[x][I[x]][y];
+ }
+#endif /* LTC_FAST */
+ }
+#endif /* GCM_TABLES_SSE2 */
+#else
+ gcm_gf_mult(gcm->H, I, T);
+#endif
+ XMEMCPY(I, T, 16);
+}
+#endif
+
+/* $Source: /cvs/libtom/libtomcrypt/src/encauth/gcm/gcm_mult_h.c,v $ */
+/* $Revision: 1.4 $ */
+/* $Date: 2006/08/23 20:40:23 $ */