diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index 4cc5ae2..20a38dc 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -64,6 +64,7 @@
 add_subdirectory(buf)
 add_subdirectory(base64)
 add_subdirectory(bytestring)
+add_subdirectory(pool)
 
 # Level 0.2 - depends on nothing but itself
 add_subdirectory(sha)
@@ -136,6 +137,7 @@
   $<TARGET_OBJECTS:err>
   $<TARGET_OBJECTS:base64>
   $<TARGET_OBJECTS:bytestring>
+  $<TARGET_OBJECTS:pool>
   $<TARGET_OBJECTS:sha>
   $<TARGET_OBJECTS:md4>
   $<TARGET_OBJECTS:md5>
diff --git a/crypto/pool/CMakeLists.txt b/crypto/pool/CMakeLists.txt
new file mode 100644
index 0000000..fe55af2
--- /dev/null
+++ b/crypto/pool/CMakeLists.txt
@@ -0,0 +1,20 @@
+include_directories(../../include)
+
+add_library(
+  pool
+
+  OBJECT
+
+  pool.c
+)
+
+add_executable(
+  pool_test
+
+  pool_test.cc
+
+  $<TARGET_OBJECTS:test_support>
+)
+
+target_link_libraries(pool_test crypto)
+add_dependencies(all_tests pool_test)
diff --git a/crypto/pool/internal.h b/crypto/pool/internal.h
new file mode 100644
index 0000000..3ec2ec2
--- /dev/null
+++ b/crypto/pool/internal.h
@@ -0,0 +1,45 @@
+/* Copyright (c) 2016, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#ifndef OPENSSL_HEADER_POOL_INTERNAL_H
+#define OPENSSL_HEADER_POOL_INTERNAL_H
+
+#include <openssl/lhash.h>
+#include <openssl/thread.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+DECLARE_LHASH_OF(CRYPTO_BUFFER);
+
+struct crypto_buffer_st {
+  CRYPTO_BUFFER_POOL *pool;
+  uint8_t *data;
+  size_t len;
+  CRYPTO_refcount_t references;
+};
+
+struct crypto_buffer_pool_st {
+  LHASH_OF(CRYPTO_BUFFER) *bufs;
+  CRYPTO_MUTEX lock;
+};
+
+
+#if defined(__cplusplus)
+} /* extern C */
+#endif
+
+#endif /* OPENSSL_HEADER_POOL_INTERNAL_H */
diff --git a/crypto/pool/pool.c b/crypto/pool/pool.c
new file mode 100644
index 0000000..ebe1b24
--- /dev/null
+++ b/crypto/pool/pool.c
@@ -0,0 +1,200 @@
+/* Copyright (c) 2016, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <openssl/pool.h>
+
+#include <assert.h>
+#include <string.h>
+
+#include <openssl/buf.h>
+#include <openssl/bytestring.h>
+#include <openssl/mem.h>
+#include <openssl/thread.h>
+
+#include "../internal.h"
+#include "internal.h"
+
+
+static uint32_t CRYPTO_BUFFER_hash(const CRYPTO_BUFFER *buf) {
+  return OPENSSL_hash32(buf->data, buf->len);
+}
+
+static int CRYPTO_BUFFER_cmp(const CRYPTO_BUFFER *a, const CRYPTO_BUFFER *b) {
+  if (a->len != b->len) {
+    return 1;
+  }
+  return memcmp(a->data, b->data, a->len);
+}
+
+CRYPTO_BUFFER_POOL* CRYPTO_BUFFER_POOL_new(void) {
+  CRYPTO_BUFFER_POOL *pool = OPENSSL_malloc(sizeof(CRYPTO_BUFFER_POOL));
+  if (pool == NULL) {
+    return NULL;
+  }
+
+  memset(pool, 0, sizeof(CRYPTO_BUFFER_POOL));
+  pool->bufs = lh_CRYPTO_BUFFER_new(CRYPTO_BUFFER_hash, CRYPTO_BUFFER_cmp);
+  if (pool->bufs == NULL) {
+    OPENSSL_free(pool);
+    return NULL;
+  }
+
+  CRYPTO_MUTEX_init(&pool->lock);
+
+  return pool;
+}
+
+void CRYPTO_BUFFER_POOL_free(CRYPTO_BUFFER_POOL *pool) {
+  if (pool == NULL) {
+    return;
+  }
+
+#if !defined(NDEBUG)
+  CRYPTO_MUTEX_lock_write(&pool->lock);
+  assert(lh_CRYPTO_BUFFER_num_items(pool->bufs) == 0);
+  CRYPTO_MUTEX_unlock_write(&pool->lock);
+#endif
+
+  lh_CRYPTO_BUFFER_free(pool->bufs);
+  CRYPTO_MUTEX_cleanup(&pool->lock);
+  OPENSSL_free(pool);
+}
+
+CRYPTO_BUFFER *CRYPTO_BUFFER_new(const uint8_t *data, size_t len,
+                                 CRYPTO_BUFFER_POOL *pool) {
+  if (pool != NULL) {
+    CRYPTO_BUFFER tmp;
+    tmp.data = (uint8_t *) data;
+    tmp.len = len;
+
+    CRYPTO_MUTEX_lock_read(&pool->lock);
+    CRYPTO_BUFFER *const duplicate =
+        lh_CRYPTO_BUFFER_retrieve(pool->bufs, &tmp);
+    if (duplicate != NULL) {
+      CRYPTO_refcount_inc(&duplicate->references);
+    }
+    CRYPTO_MUTEX_unlock_read(&pool->lock);
+
+    if (duplicate != NULL) {
+      return duplicate;
+    }
+  }
+
+  CRYPTO_BUFFER *const buf = OPENSSL_malloc(sizeof(CRYPTO_BUFFER));
+  if (buf == NULL) {
+    return NULL;
+  }
+  memset(buf, 0, sizeof(CRYPTO_BUFFER));
+
+  buf->data = BUF_memdup(data, len);
+  if (len != 0 && buf->data == NULL) {
+    OPENSSL_free(buf);
+    return NULL;
+  }
+
+  buf->len = len;
+  buf->references = 1;
+
+  if (pool == NULL) {
+    return buf;
+  }
+
+  buf->pool = pool;
+
+  CRYPTO_MUTEX_lock_write(&pool->lock);
+  CRYPTO_BUFFER *duplicate = lh_CRYPTO_BUFFER_retrieve(pool->bufs, buf);
+  int inserted = 0;
+  if (duplicate == NULL) {
+    CRYPTO_BUFFER *old = NULL;
+    inserted = lh_CRYPTO_BUFFER_insert(pool->bufs, &old, buf);
+    assert(old == NULL);
+  } else {
+    CRYPTO_refcount_inc(&duplicate->references);
+  }
+  CRYPTO_MUTEX_unlock_write(&pool->lock);
+
+  if (!inserted) {
+    /* We raced to insert |buf| into the pool and lost, or else there was an
+     * error inserting. */
+    OPENSSL_free(buf->data);
+    OPENSSL_free(buf);
+    return duplicate;
+  }
+
+  return buf;
+}
+
+CRYPTO_BUFFER* CRYPTO_BUFFER_new_from_CBS(CBS *cbs, CRYPTO_BUFFER_POOL *pool) {
+  return CRYPTO_BUFFER_new(CBS_data(cbs), CBS_len(cbs), pool);
+}
+
+void CRYPTO_BUFFER_free(CRYPTO_BUFFER *buf) {
+  if (buf == NULL) {
+    return;
+  }
+
+  CRYPTO_BUFFER_POOL *const pool = buf->pool;
+  if (pool == NULL) {
+    if (CRYPTO_refcount_dec_and_test_zero(&buf->references)) {
+      /* If a reference count of zero is observed, there cannot be a reference
+       * from any pool to this buffer and thus we are able to free this
+       * buffer. */
+      OPENSSL_free(buf->data);
+      OPENSSL_free(buf);
+    }
+
+    return;
+  }
+
+  CRYPTO_MUTEX_lock_write(&pool->lock);
+  if (!CRYPTO_refcount_dec_and_test_zero(&buf->references)) {
+    CRYPTO_MUTEX_unlock_write(&buf->pool->lock);
+    return;
+  }
+
+  /* We have an exclusive lock on the pool, therefore no concurrent lookups can
+   * find this buffer and increment the reference count. Thus, if the count is
+   * zero there are and can never be any more references and thus we can free
+   * this buffer. */
+  void *found = lh_CRYPTO_BUFFER_delete(pool->bufs, buf);
+  assert(found != NULL);
+  assert(found == buf);
+  (void)found;
+  CRYPTO_MUTEX_unlock_write(&buf->pool->lock);
+  OPENSSL_free(buf->data);
+  OPENSSL_free(buf);
+}
+
+int CRYPTO_BUFFER_up_ref(CRYPTO_BUFFER *buf) {
+  /* This is safe in the case that |buf->pool| is NULL because it's just
+   * standard reference counting in that case.
+   *
+   * This is also safe if |buf->pool| is non-NULL because, if it were racing
+   * with |CRYPTO_BUFFER_free| then the two callers must have independent
+   * references already and so the reference count will never hit zero. */
+  CRYPTO_refcount_inc(&buf->references);
+  return 1;
+}
+
+const uint8_t *CRYPTO_BUFFER_data(const CRYPTO_BUFFER *buf) {
+  return buf->data;
+}
+
+const size_t CRYPTO_BUFFER_len(const CRYPTO_BUFFER *buf) {
+  return buf->len;
+}
+
+void CRYPTO_BUFFER_init_CBS(const CRYPTO_BUFFER *buf, CBS *out) {
+  CBS_init(out, buf->data, buf->len);
+}
diff --git a/crypto/pool/pool_test.cc b/crypto/pool/pool_test.cc
new file mode 100644
index 0000000..4dfc546
--- /dev/null
+++ b/crypto/pool/pool_test.cc
@@ -0,0 +1,85 @@
+/* Copyright (c) 2016, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include <string.h>
+
+#include <openssl/pool.h>
+
+
+static bool TestUnpooled() {
+  static const uint8_t kData[4] = {1, 2, 3, 4};
+  bssl::UniquePtr<CRYPTO_BUFFER> buf(
+      CRYPTO_BUFFER_new(kData, sizeof(kData), nullptr));
+  if (!buf) {
+    return false;
+  }
+
+  if (CRYPTO_BUFFER_len(buf.get()) != sizeof(kData) ||
+      memcmp(kData, CRYPTO_BUFFER_data(buf.get()), sizeof(kData)) != 0) {
+    fprintf(stderr, "CRYPTO_BUFFER corrupted data.\n");
+    return false;
+  }
+
+  CRYPTO_BUFFER_up_ref(buf.get());
+  bssl::UniquePtr<CRYPTO_BUFFER> buf2(buf.get());
+
+  return true;
+}
+
+static bool TestEmpty() {
+  bssl::UniquePtr<CRYPTO_BUFFER> buf(CRYPTO_BUFFER_new(nullptr, 0, nullptr));
+  if (!buf) {
+    return false;
+  }
+
+  return true;
+}
+
+static bool TestPool() {
+  bssl::UniquePtr<CRYPTO_BUFFER_POOL> pool(CRYPTO_BUFFER_POOL_new());
+  if (!pool) {
+    return false;
+  }
+
+  static const uint8_t kData[4] = {1, 2, 3, 4};
+  bssl::UniquePtr<CRYPTO_BUFFER> buf(
+      CRYPTO_BUFFER_new(kData, sizeof(kData), pool.get()));
+  if (!buf) {
+    return false;
+  }
+
+  bssl::UniquePtr<CRYPTO_BUFFER> buf2(
+      CRYPTO_BUFFER_new(kData, sizeof(kData), pool.get()));
+  if (!buf2) {
+    return false;
+  }
+
+  if (buf.get() != buf2.get()) {
+    fprintf(stderr, "CRYPTO_BUFFER_POOL did not dedup data.\n");
+    return false;
+  }
+
+  return true;
+}
+
+int main(int argc, char **argv) {
+  if (!TestUnpooled() ||
+      !TestEmpty() ||
+      !TestPool()) {
+    return 1;
+  }
+
+  printf("PASS\n");
+  return 0;
+}