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authorSteven Barth <steven@midlink.org>2009-02-22 23:19:25 +0000
committerSteven Barth <steven@midlink.org>2009-02-22 23:19:25 +0000
commitd730c1263328c5990ce46cdf6394ce6e36cc3609 (patch)
tree8dc37350e69dcbd0ca82570cfa62a4c710defc93 /libs/nixio/axTLS/crypto/rc4.c
parentd2b11117f26285186b711271d24733d35e0444a1 (diff)
Add axTLS sourcecode
Diffstat (limited to 'libs/nixio/axTLS/crypto/rc4.c')
-rw-r--r--libs/nixio/axTLS/crypto/rc4.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/libs/nixio/axTLS/crypto/rc4.c b/libs/nixio/axTLS/crypto/rc4.c
new file mode 100644
index 000000000..57136b82b
--- /dev/null
+++ b/libs/nixio/axTLS/crypto/rc4.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2007, Cameron Rich
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * * Neither the name of the axTLS project nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * An implementation of the RC4/ARC4 algorithm.
+ * Originally written by Christophe Devine.
+ */
+
+#include <string.h>
+#include "crypto.h"
+
+/**
+ * Get ready for an encrypt/decrypt operation
+ */
+void RC4_setup(RC4_CTX *ctx, const uint8_t *key, int length)
+{
+ int i, j = 0, k = 0, a;
+ uint8_t *m;
+
+ ctx->x = 0;
+ ctx->y = 0;
+ m = ctx->m;
+
+ for (i = 0; i < 256; i++)
+ m[i] = i;
+
+ for (i = 0; i < 256; i++)
+ {
+ a = m[i];
+ j = (uint8_t)(j + a + key[k]);
+ m[i] = m[j];
+ m[j] = a;
+
+ if (++k >= length)
+ k = 0;
+ }
+}
+
+/**
+ * Perform the encrypt/decrypt operation (can use it for either since
+ * this is a stream cipher).
+ */
+void RC4_crypt(RC4_CTX *ctx, const uint8_t *msg, uint8_t *out, int length)
+{
+ int i;
+ uint8_t *m, x, y, a, b;
+ out = (uint8_t *)msg;
+
+ x = ctx->x;
+ y = ctx->y;
+ m = ctx->m;
+
+ for (i = 0; i < length; i++)
+ {
+ a = m[++x];
+ y += a;
+ m[x] = b = m[y];
+ m[y] = a;
+ out[i] ^= m[(uint8_t)(a + b)];
+ }
+
+ ctx->x = x;
+ ctx->y = y;
+}