summaryrefslogtreecommitdiffabout
path: root/pwmanager/libcrypt/cipher/arcfour.c
Side-by-side diff
Diffstat (limited to 'pwmanager/libcrypt/cipher/arcfour.c') (more/less context) (ignore whitespace changes)
-rw-r--r--pwmanager/libcrypt/cipher/arcfour.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/pwmanager/libcrypt/cipher/arcfour.c b/pwmanager/libcrypt/cipher/arcfour.c
new file mode 100644
index 0000000..6bb0555
--- a/dev/null
+++ b/pwmanager/libcrypt/cipher/arcfour.c
@@ -0,0 +1,156 @@
+/* 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"
+
+static const char *selftest(void);
+
+typedef struct {
+ int idx_i, idx_j;
+ byte sbox[256];
+} ARCFOUR_context;
+
+static void
+do_encrypt_stream( ARCFOUR_context *ctx,
+ byte *outbuf, const byte *inbuf, unsigned int length )
+{
+ 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;
+}
+
+static void
+encrypt_stream (void *context,
+ byte *outbuf, const byte *inbuf, unsigned int length)
+{
+ ARCFOUR_context *ctx = (ARCFOUR_context *) context;
+ do_encrypt_stream (ctx, outbuf, inbuf, length );
+ _gcry_burn_stack (64);
+}
+
+
+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=0; i < 256; i++ )
+ karr[i] = key[i%keylen];
+ for (i=j=0; i < 256; i++ )
+ {
+ int t;
+ j = (j + ctx->sbox[i] + karr[i]) % 256;
+ t = ctx->sbox[i];
+ ctx->sbox[i] = ctx->sbox[j];
+ ctx->sbox[j] = t;
+ }
+ memset( karr, 0, 256 );
+
+ 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 );
+ _gcry_burn_stack (300);
+ 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 byte key_1[] =
+ { 0x61, 0x8A, 0x63, 0xD2, 0xFB };
+ static 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 =
+ {
+ "ARCFOUR", NULL, NULL, 1, 128, sizeof (ARCFOUR_context),
+ arcfour_setkey, NULL, NULL, encrypt_stream, encrypt_stream,
+ };
+