1// SPDX-License-Identifier: GPL-2.0
2/* net/atm/raw.c - Raw AAL0 and AAL5 transports */
3
4/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
7
8#include <linux/module.h>
9#include <linux/atmdev.h>
10#include <linux/capability.h>
11#include <linux/kernel.h>
12#include <linux/skbuff.h>
13#include <linux/mm.h>
14#include <linux/slab.h>
15
16#include "common.h"
17#include "protocols.h"
18
19/*
20 * SKB == NULL indicates that the link is being closed
21 */
22
23static void atm_push_raw(struct atm_vcc *vcc, struct sk_buff *skb)
24{
25	if (skb) {
26		struct sock *sk = sk_atm(vcc);
27
28		skb_queue_tail(&sk->sk_receive_queue, skb);
29		sk->sk_data_ready(sk);
30	}
31}
32
33static void atm_pop_raw(struct atm_vcc *vcc, struct sk_buff *skb)
34{
35	struct sock *sk = sk_atm(vcc);
36
37	pr_debug("(%d) %d -= %d\n",
38		 vcc->vci, sk_wmem_alloc_get(sk), ATM_SKB(skb)->acct_truesize);
39	WARN_ON(refcount_sub_and_test(ATM_SKB(skb)->acct_truesize, &sk->sk_wmem_alloc));
40	dev_kfree_skb_any(skb);
41	sk->sk_write_space(sk);
42}
43
44static int atm_send_aal0(struct atm_vcc *vcc, struct sk_buff *skb)
45{
46	/*
47	 * Note that if vpi/vci are _ANY or _UNSPEC the below will
48	 * still work
49	 */
50	if (!capable(CAP_NET_ADMIN) &&
51	    (((u32 *)skb->data)[0] & (ATM_HDR_VPI_MASK | ATM_HDR_VCI_MASK)) !=
52	    ((vcc->vpi << ATM_HDR_VPI_SHIFT) |
53	     (vcc->vci << ATM_HDR_VCI_SHIFT))) {
54		kfree_skb(skb);
55		return -EADDRNOTAVAIL;
56	}
57	if (vcc->dev->ops->send_bh)
58		return vcc->dev->ops->send_bh(vcc, skb);
59	return vcc->dev->ops->send(vcc, skb);
60}
61
62int atm_init_aal0(struct atm_vcc *vcc)
63{
64	vcc->push = atm_push_raw;
65	vcc->pop = atm_pop_raw;
66	vcc->push_oam = NULL;
67	vcc->send = atm_send_aal0;
68	return 0;
69}
70
71int atm_init_aal34(struct atm_vcc *vcc)
72{
73	vcc->push = atm_push_raw;
74	vcc->pop = atm_pop_raw;
75	vcc->push_oam = NULL;
76	if (vcc->dev->ops->send_bh)
77		vcc->send = vcc->dev->ops->send_bh;
78	else
79		vcc->send = vcc->dev->ops->send;
80	return 0;
81}
82
83int atm_init_aal5(struct atm_vcc *vcc)
84{
85	vcc->push = atm_push_raw;
86	vcc->pop = atm_pop_raw;
87	vcc->push_oam = NULL;
88	if (vcc->dev->ops->send_bh)
89		vcc->send = vcc->dev->ops->send_bh;
90	else
91		vcc->send = vcc->dev->ops->send;
92	return 0;
93}
94EXPORT_SYMBOL(atm_init_aal5);
95