* #35924: added zrtp module build instructions
diff --git a/jni/libzrtp/srtp/crypto/macSkein.h b/jni/libzrtp/srtp/crypto/macSkein.h
new file mode 100644
index 0000000..71c2ad9
--- /dev/null
+++ b/jni/libzrtp/srtp/crypto/macSkein.h
@@ -0,0 +1,148 @@
+/*
+ Copyright (C) 2010 Werner Dittmann
+
+ This program is free software: 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 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+
+#ifndef MAC_SKEIN_H
+#define MAC_SKEIN_H
+
+#include <crypto/skeinApi.h>
+/**
+ * @file macSkein.h
+ * @brief Function that provide Skein MAC support
+ *
+ *
+ * Functions to compute Skein MAC.
+ *
+ * @ingroup GNU_ZRTP
+ * @{
+ */
+
+/**
+ * Compute Skein MAC.
+ *
+ * This functions takes one data chunk and computes its Skein MAC.
+ *
+ * @param key
+ * The MAC key.
+ * @param key_length
+ * Lneght of the MAC key in bytes
+ * @param data
+ * Points to the data chunk.
+ * @param data_length
+ * Length of the data in bytes
+ * @param mac
+ * Points to a buffer that receives the computed digest.
+ * @param mac_length
+ * Integer that contains the length of the MAC in bits (not bytes).
+ * @param skeinSize
+ * The Skein size to use.
+ */
+void macSkein( uint8_t* key, int32_t key_length,
+ const uint8_t* data, uint32_t data_length,
+ uint8_t* mac, int32_t mac_length, SkeinSize_t skeinSize );
+
+/**
+ * Compute Skein MAC over several data cunks.
+ *
+ * This functions takes several data chunk and computes the Skein MAC.
+ *
+ * @param key
+ * The MAC key.
+ * @param key_length
+ * Lneght of the MAC key in bytes
+ * @param data
+ * Points to an array of pointers that point to the data chunks. A NULL
+ * pointer in an array element terminates the data chunks.
+ * @param data_length
+ * Points to an array of integers that hold the length of each data chunk.
+ * @param mac
+ * Points to a buffer that receives the computed digest.
+ * @param mac_length
+ * Integer that contains the length of the MAC in bits (not bytes).
+ * @param skeinSize
+ * The Skein size to use.
+ */
+void macSkein( uint8_t* key, int32_t key_length,
+ const uint8_t* data[], uint32_t data_length[],
+ uint8_t* mac, int32_t mac_length, SkeinSize_t skeinSize);
+
+/**
+ * Create and initialize a Skein MAC context.
+ *
+ * An application uses this context to hash several data with on Skein MAC
+ * Context with the same key, key length and mac length
+ *
+ * @param key
+ * The MAC key.
+ * @param key_length
+ * Lenght of the MAC key in bytes
+ * @param mac_length
+ * Integer that contains the length of the MAC in bits (not bytes).
+ * @param skeinSize
+ * The Skein size to use.
+ * @return Returns a pointer to the initialized context
+ */
+void* createSkeinMacContext(uint8_t* key, int32_t key_length,
+ int32_t mac_length, SkeinSize_t skeinSize);
+
+/**
+ * Compute Skein MAC.
+ *
+ * This functions takes one data chunk and computes its Skein MAC.
+ *
+ * @param ctx
+ * Pointer to initialized Skein MAC context
+ * @param data
+ * Points to the data chunk.
+ * @param data_length
+ * Length of the data in bytes
+ * @param mac
+ * Points to a buffer that receives the computed digest.
+ */
+
+void macSkeinCtx(void* ctx, const uint8_t* data, uint32_t data_length,
+ uint8_t* mac);
+
+/**
+ * Compute Skein MAC over several data cunks.
+ *
+ * This functions takes several data chunk and computes the SHA1 HAMAC.
+ *
+ * @param ctx
+ * Pointer to initialized Skein MAC context
+ * @param data
+ * Points to an array of pointers that point to the data chunks. A NULL
+ * pointer in an array element terminates the data chunks.
+ * @param data_length
+ * Points to an array of integers that hold the length of each data chunk.
+ * @param mac
+ * Points to a buffer that receives the computed digest.
+ */
+void macSkeinCtx(void* ctx, const uint8_t* data[], uint32_t data_length[],
+ uint8_t* mac);
+
+/**
+ * Free Skein MAC context.
+ *
+ * @param ctx a pointer to Skein MAC context
+ */
+void freeSkeinMacContext(void* ctx);
+
+/**
+ * @}
+ */
+#endif
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