1 files changed, 227 insertions, 0 deletions
diff --git a/libotr/libgcrypt-1.8.7/cipher/arcfour.c b/libotr/libgcrypt-1.8.7/cipher/arcfour.c
new file mode 100644
index 0000000..44e8ef4
--- /dev/null
+++ b/libotr/libgcrypt-1.8.7/cipher/arcfour.c
@@ -0,0 +1,227 @@
+/* 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"
+
+/* 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)
+{
+#ifdef HAVE_COMPATIBLE_GCC_WIN64_PLATFORM_AS
+  const void *fn = _gcry_arcfour_amd64;
+  /* Call SystemV ABI function without storing non-volatile XMM registers,
+   * as target function does not use vector instruction sets. */
+  asm volatile ("callq *%0\n\t"
+                : "+a" (fn),
+                  "+D" (context),
+                  "+S" (length),
+                  "+d" (inbuf),
+                  "+c" (outbuf)
+                :
+                : "cc", "memory", "r8", "r9", "r10", "r11");
+#else
+  _gcry_arcfour_amd64 (context, length, inbuf, outbuf );
+#endif
+}
+
+#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 )
+{
+  ARCFOUR_context *ctx = (ARCFOUR_context *) context;
+  gcry_err_code_t rc = do_arcfour_setkey (ctx, key, keylen );
+  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));
+  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));
+  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,
+  };