add srtp

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@1086 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/srtp/crypto/include/rand_source.h

@@ -0,0 +1,91 @@
+/*
+ * rand_source.h
+ *
+ * implements a random source based on /dev/random
+ *
+ * David A. McGrew
+ * Cisco Systems, Inc.
+ */
+/*
+ *	
+ * Copyright(c) 2001-2005 Cisco Systems, Inc.
+ * 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 Cisco Systems, Inc. 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 HOLDERS 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.
+ *
+ */
+
+
+#ifndef RAND_SOURCE
+#define RAND_SOURCE
+
+#include "err.h"
+#include "datatypes.h"
+
+err_status_t
+rand_source_init(void);
+
+/*
+ * rand_source_get_octet_string() writes a random octet string.
+ *
+ * The function call rand_source_get_octet_string(dest, len) writes
+ * len octets of random data to the location to which dest points,
+ * and returns an error code.  This error code should be checked,
+ * and if a failure is reported, the data in the buffer MUST NOT
+ * be used.
+ * 
+ * warning: If the return code is not checked, then non-random
+ *          data may inadvertently be used.
+ *
+ * returns:
+ *     - err_status_ok    if no problems occured.
+ *     - [other]          a problem occured, and no assumptions should
+ *                        be made about the contents of the destination
+ *                        buffer.
+ */
+
+err_status_t
+rand_source_get_octet_string(void *dest, uint32_t length);
+
+err_status_t
+rand_source_deinit(void);
+
+/* 
+ * function prototype for a random source function
+ *
+ * A rand_source_func_t writes num_octets at the location indicated by
+ * dest and returns err_status_ok.  Any other return value indicates
+ * failure.
+ */
+
+typedef err_status_t (*rand_source_func_t)
+     (void *dest, uint32_t num_octets);
+
+#endif /* RAND_SOURCE */