// SPDX-License-Identifier: GPL-2.0

  /* net/atm/raw.c - Raw AAL0 and AAL5 transports */
  
  /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */

  #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

  
  #include <linux/module.h>

  #include <linux/atmdev.h>

  #include <linux/capability.h>

  #include <linux/kernel.h>
  #include <linux/skbuff.h>
  #include <linux/mm.h>

  #include <linux/slab.h>

  
  #include "common.h"
  #include "protocols.h"

  /*
   * SKB == NULL indicates that the link is being closed
   */

  static void atm_push_raw(struct atm_vcc *vcc, struct sk_buff *skb)

  {
  	if (skb) {
  		struct sock *sk = sk_atm(vcc);
  
  		skb_queue_tail(&sk->sk_receive_queue, skb);

  		sk->sk_data_ready(sk);

  	}
  }

  static void atm_pop_raw(struct atm_vcc *vcc, struct sk_buff *skb)

  {
  	struct sock *sk = sk_atm(vcc);

  	pr_debug("(%d) %d -= %d
  ",

  		 vcc->vci, sk_wmem_alloc_get(sk), ATM_SKB(skb)->acct_truesize);
  	WARN_ON(refcount_sub_and_test(ATM_SKB(skb)->acct_truesize, &sk->sk_wmem_alloc));

  	dev_kfree_skb_any(skb);
  	sk->sk_write_space(sk);
  }

  static int atm_send_aal0(struct atm_vcc *vcc, struct sk_buff *skb)

  {
  	/*
  	 * Note that if vpi/vci are _ANY or _UNSPEC the below will
  	 * still work
  	 */
  	if (!capable(CAP_NET_ADMIN) &&

  	    (((u32 *)skb->data)[0] & (ATM_HDR_VPI_MASK | ATM_HDR_VCI_MASK)) !=
  	    ((vcc->vpi << ATM_HDR_VPI_SHIFT) |
  	     (vcc->vci << ATM_HDR_VCI_SHIFT))) {

  		kfree_skb(skb);
  		return -EADDRNOTAVAIL;

  	}

  	return vcc->dev->ops->send(vcc, skb);

  }

  int atm_init_aal0(struct atm_vcc *vcc)
  {
  	vcc->push = atm_push_raw;
  	vcc->pop = atm_pop_raw;
  	vcc->push_oam = NULL;
  	vcc->send = atm_send_aal0;
  	return 0;
  }

  int atm_init_aal34(struct atm_vcc *vcc)
  {
  	vcc->push = atm_push_raw;
  	vcc->pop = atm_pop_raw;
  	vcc->push_oam = NULL;
  	vcc->send = vcc->dev->ops->send;
  	return 0;
  }

  int atm_init_aal5(struct atm_vcc *vcc)
  {
  	vcc->push = atm_push_raw;
  	vcc->pop = atm_pop_raw;
  	vcc->push_oam = NULL;
  	vcc->send = vcc->dev->ops->send;
  	return 0;
  }

  EXPORT_SYMBOL(atm_init_aal5);