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diff --git a/src/vppinfra/random_buffer.h b/src/vppinfra/random_buffer.h
new file mode 100644
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+++ b/src/vppinfra/random_buffer.h
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+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/*
+  Copyright (c) 2005 Eliot Dresselhaus
+
+  Permission is hereby granted, free of charge, to any person obtaining
+  a copy of this software and associated documentation files (the
+  "Software"), to deal in the Software without restriction, including
+  without limitation the rights to use, copy, modify, merge, publish,
+  distribute, sublicense, and/or sell copies of the Software, and to
+  permit persons to whom the Software is furnished to do so, subject to
+  the following conditions:
+
+  The above copyright notice and this permission notice shall be
+  included in all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#ifndef included_clib_random_buffer_h
+#define included_clib_random_buffer_h
+
+#include <vppinfra/clib.h>
+#include <vppinfra/random_isaac.h>
+
+typedef struct
+{
+  /* Two parallel ISAAC contexts for speed. */
+  isaac_t ctx[2];
+
+  /* Random buffer. */
+  uword *buffer;
+
+  /* Cache up to 1 word worth of bytes for random data
+     less than one word at a time. */
+  uword n_cached_bytes;
+
+  union
+  {
+    u8 cached_bytes[sizeof (uword)];
+    uword cached_word;
+  };
+}
+clib_random_buffer_t;
+
+always_inline void
+clib_random_buffer_free (clib_random_buffer_t * b)
+{
+  vec_free (b->buffer);
+}
+
+/* Fill random buffer. */
+void clib_random_buffer_fill (clib_random_buffer_t * b, uword n_words);
+
+/* Initialize random buffer. */
+void clib_random_buffer_init (clib_random_buffer_t * b, uword seed);
+
+/* Returns word aligned random data, possibly filling buffer. */
+always_inline void *
+clib_random_buffer_get_data (clib_random_buffer_t * b, uword n_bytes)
+{
+  uword n_words, i, l;
+
+  l = b->n_cached_bytes;
+  if (n_bytes <= l)
+    {
+      b->n_cached_bytes = l - n_bytes;
+      return &b->cached_bytes[l];
+    }
+
+  n_words = n_bytes / sizeof (uword);
+  if (n_bytes % sizeof (uword))
+    n_words++;
+
+  /* Enough random words left? */
+  if (PREDICT_FALSE (n_words > vec_len (b->buffer)))
+    clib_random_buffer_fill (b, n_words);
+
+  i = vec_len (b->buffer) - n_words;
+  _vec_len (b->buffer) = i;
+
+  if (n_bytes < sizeof (uword))
+    {
+      b->cached_word = b->buffer[i];
+      b->n_cached_bytes = sizeof (uword) - n_bytes;
+      return b->cached_bytes;
+    }
+  else
+    return b->buffer + i;
+}
+
+#endif /* included_clib_random_buffer_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */