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-rw-r--r--utils/ipodpatcher/arc4.c108
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diff --git a/utils/ipodpatcher/arc4.c b/utils/ipodpatcher/arc4.c
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+/*
+ * arc4.c
+ * Release $Name: MATRIXSSL_1_8_3_OPEN $
+ *
+ * ARC4 stream cipher implementation
+ */
+/*
+ * Copyright (c) PeerSec Networks, 2002-2007. All Rights Reserved.
+ * The latest version of this code is available at http://www.matrixssl.org
+ *
+ * This software is open source; 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.
+ *
+ * This General Public License does NOT permit incorporating this software
+ * into proprietary programs. If you are unable to comply with the GPL, a
+ * commercial license for this software may be purchased from PeerSec Networks
+ * at http://www.peersec.com
+ *
+ * This program is distributed in 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
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+/******************************************************************************/
+
+#include "arc4.h"
+
+/*
+ Some accounts, such as O'Reilly's Secure Programming Cookbook say that no
+ more than 2^30 bytes should be processed without rekeying, so we
+ enforce that limit here. FYI, this is equal to 1GB of data transferred.
+*/
+#define ARC4_MAX_BYTES 0x40000000
+
+/******************************************************************************/
+/*
+ SSL_RSA_WITH_RC4_* cipher callbacks
+ */
+void matrixArc4Init(struct rc4_key_t *ctx, unsigned char *key, int32_t keylen)
+{
+ unsigned char index1, index2, tmp, *state;
+ int16_t counter;
+
+ ctx->byteCount = 0;
+ state = &ctx->state[0];
+
+ for (counter = 0; counter < 256; counter++) {
+ state[counter] = (unsigned char)counter;
+ }
+ ctx->x = 0;
+ ctx->y = 0;
+ index1 = 0;
+ index2 = 0;
+
+ for (counter = 0; counter < 256; counter++) {
+ index2 = (key[index1] + state[counter] + index2) & 0xff;
+
+ tmp = state[counter];
+ state[counter] = state[index2];
+ state[index2] = tmp;
+
+ index1 = (index1 + 1) % keylen;
+ }
+}
+
+int32_t matrixArc4(struct rc4_key_t *ctx, unsigned char *in,
+ unsigned char *out, int32_t len)
+{
+ unsigned char x, y, *state, xorIndex, tmp;
+ int counter; /* NOTE BY DAVE CHAPMAN: This was a short in
+ the original code, which caused a segfault
+ when attempting to process data > 32767
+ bytes. */
+
+ ctx->byteCount += len;
+ if (ctx->byteCount > ARC4_MAX_BYTES) {
+ return -1;
+ }
+
+ x = ctx->x;
+ y = ctx->y;
+ state = &ctx->state[0];
+ for (counter = 0; counter < len; counter++) {
+ x = (x + 1) & 0xff;
+ y = (state[x] + y) & 0xff;
+
+ tmp = state[x];
+ state[x] = state[y];
+ state[y] = tmp;
+
+ xorIndex = (state[x] + state[y]) & 0xff;
+
+ tmp = in[counter];
+ tmp ^= state[xorIndex];
+ out[counter] = tmp;
+ }
+ ctx->x = x;
+ ctx->y = y;
+ return len;
+}
+
+/*****************************************************************************/