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diff --git a/src/core/tsi/ssl/session_cache/ssl_session_cache.h b/src/core/tsi/ssl/session_cache/ssl_session_cache.h
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+++ b/src/core/tsi/ssl/session_cache/ssl_session_cache.h
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+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * 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.
+ *
+ */
+
+#ifndef GRPC_CORE_TSI_SSL_SESSION_CACHE_SSL_SESSION_CACHE_H
+#define GRPC_CORE_TSI_SSL_SESSION_CACHE_SSL_SESSION_CACHE_H
+
+#include <grpc/support/port_platform.h>
+
+#include <grpc/slice.h>
+#include <grpc/support/sync.h>
+
+extern "C" {
+#include <openssl/ssl.h>
+}
+
+#include "src/core/lib/avl/avl.h"
+#include "src/core/lib/gprpp/memory.h"
+#include "src/core/lib/gprpp/ref_counted.h"
+#include "src/core/tsi/ssl/session_cache/ssl_session.h"
+
+/// Cache for SSL sessions for sessions resumption.
+///
+/// Older sessions may be evicted from the cache using LRU policy if capacity
+/// limit is hit. All sessions are associated with some key, usually server
+/// name. Note that servers are required to share session ticket encryption keys
+/// in order for cache to be effective.
+///
+/// This class is thread safe.
+
+namespace tsi {
+
+class SslSessionLRUCache : public grpc_core::RefCounted<SslSessionLRUCache> {
+ public:
+  /// Create new LRU cache with the given capacity.
+  static grpc_core::RefCountedPtr<SslSessionLRUCache> Create(size_t capacity) {
+    return grpc_core::MakeRefCounted<SslSessionLRUCache>(capacity);
+  }
+
+  // Not copyable nor movable.
+  SslSessionLRUCache(const SslSessionLRUCache&) = delete;
+  SslSessionLRUCache& operator=(const SslSessionLRUCache&) = delete;
+
+  /// Returns current number of sessions in the cache.
+  size_t Size();
+  /// Add \a session in the cache using \a key. This operation may discard older
+  /// sessions.
+  void Put(const char* key, SslSessionPtr session);
+  /// Returns the session from the cache associated with \a key or null if not
+  /// found.
+  SslSessionPtr Get(const char* key);
+
+ private:
+  // So New() can call our private ctor.
+  template <typename T, typename... Args>
+  friend T* grpc_core::New(Args&&... args);
+
+  // So Delete() can call our private dtor.
+  template <typename T>
+  friend void grpc_core::Delete(T*);
+
+  class Node;
+
+  explicit SslSessionLRUCache(size_t capacity);
+  ~SslSessionLRUCache();
+
+  Node* FindLocked(const grpc_slice& key);
+  void Remove(Node* node);
+  void PushFront(Node* node);
+  void AssertInvariants();
+
+  gpr_mu lock_;
+  size_t capacity_;
+
+  Node* use_order_list_head_ = nullptr;
+  Node* use_order_list_tail_ = nullptr;
+  size_t use_order_list_size_ = 0;
+  grpc_avl entry_by_key_;
+};
+
+}  // namespace tsi
+
+#endif /* GRPC_CORE_TSI_SSL_SESSION_CACHE_SSL_SESSION_CACHE_H */