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diff --git a/comm/third_party/libgcrypt/cipher/arcfour.c b/comm/third_party/libgcrypt/cipher/arcfour.c
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+/* arcfour.c - The arcfour stream cipher
+ * Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
+ * This file is part of Libgcrypt.
+ *
+ * Libgcrypt is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser general Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * Libgcrypt 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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
+ *
+ * For a description of the algorithm, see:
+ * Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1996.
+ * ISBN 0-471-11709-9. Pages 397 ff.
+ */
+
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "types.h"
+#include "g10lib.h"
+#include "cipher.h"
+#include "cipher-internal.h"
+
+/* USE_AMD64_ASM indicates whether to use AMD64 assembly code. */
+#undef USE_AMD64_ASM
+#if defined(__x86_64__) && (defined(HAVE_COMPATIBLE_GCC_AMD64_PLATFORM_AS) || \
+ defined(HAVE_COMPATIBLE_GCC_WIN64_PLATFORM_AS))
+# define USE_AMD64_ASM 1
+#endif
+
+static const char *selftest(void);
+
+#ifdef USE_AMD64_ASM
+
+typedef struct {
+ u32 sbox[256];
+ u32 idx_i, idx_j;
+} ARCFOUR_context;
+
+void _gcry_arcfour_amd64(void *key, size_t len, const byte *indata,
+ byte *outdata);
+
+static void
+encrypt_stream (void *context,
+ byte *outbuf, const byte *inbuf, size_t length)
+{
+ _gcry_arcfour_amd64 (context, length, inbuf, outbuf );
+}
+
+#else /*!USE_AMD64_ASM*/
+
+typedef struct {
+ byte sbox[256];
+ int idx_i, idx_j;
+} ARCFOUR_context;
+
+static void
+do_encrypt_stream( ARCFOUR_context *ctx,
+ byte *outbuf, const byte *inbuf, size_t length )
+{
+#ifndef __i386__
+ register unsigned int i = ctx->idx_i;
+ register byte j = ctx->idx_j;
+ register byte *sbox = ctx->sbox;
+ register byte t, u;
+
+ while ( length-- )
+ {
+ i++;
+ t = sbox[(byte)i];
+ j += t;
+ u = sbox[j];
+ sbox[(byte)i] = u;
+ u += t;
+ sbox[j] = t;
+ *outbuf++ = sbox[u] ^ *inbuf++;
+ }
+
+ ctx->idx_i = (byte)i;
+ ctx->idx_j = (byte)j;
+#else /*__i386__*/
+ /* Old implementation of arcfour is faster on i386 than the version above.
+ * This is because version above increases register pressure which on i386
+ * would push some of the variables to memory/stack. Therefore keep this
+ * version for i386 to avoid regressing performance. */
+ register int i = ctx->idx_i;
+ register int j = ctx->idx_j;
+ register byte *sbox = ctx->sbox;
+ register int t;
+
+ while ( length-- )
+ {
+ i++;
+ i = i & 255; /* The and-op seems to be faster than the mod-op. */
+ j += sbox[i];
+ j &= 255;
+ t = sbox[i]; sbox[i] = sbox[j]; sbox[j] = t;
+ *outbuf++ = *inbuf++ ^ sbox[(sbox[i] + sbox[j]) & 255];
+ }
+
+ ctx->idx_i = i;
+ ctx->idx_j = j;
+#endif
+}
+
+static void
+encrypt_stream (void *context,
+ byte *outbuf, const byte *inbuf, size_t length)
+{
+ ARCFOUR_context *ctx = (ARCFOUR_context *) context;
+ do_encrypt_stream (ctx, outbuf, inbuf, length );
+ _gcry_burn_stack (64);
+}
+
+#endif /*!USE_AMD64_ASM*/
+
+
+static gcry_err_code_t
+do_arcfour_setkey (void *context, const byte *key, unsigned int keylen)
+{
+ static int initialized;
+ static const char* selftest_failed;
+ int i, j;
+ byte karr[256];
+ ARCFOUR_context *ctx = (ARCFOUR_context *) context;
+
+ if (!initialized )
+ {
+ initialized = 1;
+ selftest_failed = selftest();
+ if( selftest_failed )
+ log_error ("ARCFOUR selftest failed (%s)\n", selftest_failed );
+ }
+ if( selftest_failed )
+ return GPG_ERR_SELFTEST_FAILED;
+
+ if( keylen < 40/8 ) /* we want at least 40 bits */
+ return GPG_ERR_INV_KEYLEN;
+
+ ctx->idx_i = ctx->idx_j = 0;
+ for (i=0; i < 256; i++ )
+ ctx->sbox[i] = i;
+ for (i=j=0; i < 256; i++,j++ )
+ {
+ if (j >= keylen)
+ j = 0;
+ karr[i] = key[j];
+ }
+ for (i=j=0; i < 256; i++ )
+ {
+ int t;
+ j = (j + ctx->sbox[i] + karr[i]) & 255;
+ t = ctx->sbox[i];
+ ctx->sbox[i] = ctx->sbox[j];
+ ctx->sbox[j] = t;
+ }
+ wipememory( karr, sizeof(karr) );
+
+ return GPG_ERR_NO_ERROR;
+}
+
+static gcry_err_code_t
+arcfour_setkey ( void *context, const byte *key, unsigned int keylen,
+ cipher_bulk_ops_t *bulk_ops )
+{
+ ARCFOUR_context *ctx = (ARCFOUR_context *) context;
+ gcry_err_code_t rc = do_arcfour_setkey (ctx, key, keylen );
+ (void)bulk_ops;
+ return rc;
+}
+
+
+static const char*
+selftest(void)
+{
+ ARCFOUR_context ctx;
+ byte scratch[16];
+
+ /* Test vector from Cryptlib labeled there: "from the
+ State/Commerce Department". */
+ static const byte key_1[] =
+ { 0x61, 0x8A, 0x63, 0xD2, 0xFB };
+ static const byte plaintext_1[] =
+ { 0xDC, 0xEE, 0x4C, 0xF9, 0x2C };
+ static const byte ciphertext_1[] =
+ { 0xF1, 0x38, 0x29, 0xC9, 0xDE };
+
+ arcfour_setkey( &ctx, key_1, sizeof(key_1), NULL);
+ encrypt_stream( &ctx, scratch, plaintext_1, sizeof(plaintext_1));
+ if ( memcmp (scratch, ciphertext_1, sizeof (ciphertext_1)))
+ return "Arcfour encryption test 1 failed.";
+ arcfour_setkey( &ctx, key_1, sizeof(key_1), NULL);
+ encrypt_stream(&ctx, scratch, scratch, sizeof(plaintext_1)); /* decrypt */
+ if ( memcmp (scratch, plaintext_1, sizeof (plaintext_1)))
+ return "Arcfour decryption test 1 failed.";
+ return NULL;
+}
+
+
+gcry_cipher_spec_t _gcry_cipher_spec_arcfour =
+ {
+ GCRY_CIPHER_ARCFOUR, {0, 0},
+ "ARCFOUR", NULL, NULL, 1, 128, sizeof (ARCFOUR_context),
+ arcfour_setkey, NULL, NULL, encrypt_stream, encrypt_stream,
+ };