/*
   * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
   * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     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.
   *
   * 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.
   */
  
  #include <linux/list.h>
  #include <linux/rcupdate.h>
  #include <linux/spinlock.h>
  #include <net/inet_connection_sock.h>
  #include <net/tls.h>
  #include <net/tls_toe.h>
  
  static LIST_HEAD(device_list);
  static DEFINE_SPINLOCK(device_spinlock);

  static void tls_toe_sk_destruct(struct sock *sk)

  {
  	struct inet_connection_sock *icsk = inet_csk(sk);
  	struct tls_context *ctx = tls_get_ctx(sk);
  
  	ctx->sk_destruct(sk);
  	/* Free ctx */
  	rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
  	tls_ctx_free(sk, ctx);
  }

  int tls_toe_bypass(struct sock *sk)

  {
  	struct tls_toe_device *dev;
  	struct tls_context *ctx;
  	int rc = 0;
  
  	spin_lock_bh(&device_spinlock);
  	list_for_each_entry(dev, &device_list, dev_list) {
  		if (dev->feature && dev->feature(dev)) {
  			ctx = tls_ctx_create(sk);
  			if (!ctx)
  				goto out;
  
  			ctx->sk_destruct = sk->sk_destruct;

  			sk->sk_destruct = tls_toe_sk_destruct;

  			ctx->rx_conf = TLS_HW_RECORD;
  			ctx->tx_conf = TLS_HW_RECORD;
  			update_sk_prot(sk, ctx);
  			rc = 1;
  			break;
  		}
  	}
  out:
  	spin_unlock_bh(&device_spinlock);
  	return rc;
  }

  void tls_toe_unhash(struct sock *sk)

  {
  	struct tls_context *ctx = tls_get_ctx(sk);
  	struct tls_toe_device *dev;
  
  	spin_lock_bh(&device_spinlock);
  	list_for_each_entry(dev, &device_list, dev_list) {
  		if (dev->unhash) {
  			kref_get(&dev->kref);
  			spin_unlock_bh(&device_spinlock);
  			dev->unhash(dev, sk);
  			kref_put(&dev->kref, dev->release);
  			spin_lock_bh(&device_spinlock);
  		}
  	}
  	spin_unlock_bh(&device_spinlock);
  	ctx->sk_proto->unhash(sk);
  }

  int tls_toe_hash(struct sock *sk)

  {
  	struct tls_context *ctx = tls_get_ctx(sk);
  	struct tls_toe_device *dev;
  	int err;
  
  	err = ctx->sk_proto->hash(sk);
  	spin_lock_bh(&device_spinlock);
  	list_for_each_entry(dev, &device_list, dev_list) {
  		if (dev->hash) {
  			kref_get(&dev->kref);
  			spin_unlock_bh(&device_spinlock);
  			err |= dev->hash(dev, sk);
  			kref_put(&dev->kref, dev->release);
  			spin_lock_bh(&device_spinlock);
  		}
  	}
  	spin_unlock_bh(&device_spinlock);
  
  	if (err)

  		tls_toe_unhash(sk);

  	return err;
  }
  
  void tls_toe_register_device(struct tls_toe_device *device)
  {
  	spin_lock_bh(&device_spinlock);
  	list_add_tail(&device->dev_list, &device_list);
  	spin_unlock_bh(&device_spinlock);
  }
  EXPORT_SYMBOL(tls_toe_register_device);
  
  void tls_toe_unregister_device(struct tls_toe_device *device)
  {
  	spin_lock_bh(&device_spinlock);
  	list_del(&device->dev_list);
  	spin_unlock_bh(&device_spinlock);
  }
  EXPORT_SYMBOL(tls_toe_unregister_device);