net/atm/raw.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /* net/atm/raw.c - Raw AAL0 and AAL5 transports */
0003
0004 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
0005
0006 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
0007
0008 #include <linux/module.h>
0009 #include <linux/atmdev.h>
0010 #include <linux/capability.h>
0011 #include <linux/kernel.h>
0012 #include <linux/skbuff.h>
0013 #include <linux/mm.h>
0014 #include <linux/slab.h>
0015
0016 #include "common.h"
0017 #include "protocols.h"
0018
0019 /*
0020  * SKB == NULL indicates that the link is being closed
0021  */
0022
0023 static void atm_push_raw(struct atm_vcc *vcc, struct sk_buff *skb)
0024 {
0025     if (skb) {
0026         struct sock *sk = sk_atm(vcc);
0027
0028         skb_queue_tail(&sk->sk_receive_queue, skb);
0029         sk->sk_data_ready(sk);
0030     }
0031 }
0032
0033 static void atm_pop_raw(struct atm_vcc *vcc, struct sk_buff *skb)
0034 {
0035     struct sock *sk = sk_atm(vcc);
0036
0037     pr_debug("(%d) %d -= %d\n",
0038          vcc->vci, sk_wmem_alloc_get(sk), ATM_SKB(skb)->acct_truesize);
0039     WARN_ON(refcount_sub_and_test(ATM_SKB(skb)->acct_truesize, &sk->sk_wmem_alloc));
0040     dev_kfree_skb_any(skb);
0041     sk->sk_write_space(sk);
0042 }
0043
0044 static int atm_send_aal0(struct atm_vcc *vcc, struct sk_buff *skb)
0045 {
0046     /*
0047      * Note that if vpi/vci are _ANY or _UNSPEC the below will
0048      * still work
0049      */
0050     if (!capable(CAP_NET_ADMIN) &&
0051         (((u32 *)skb->data)[0] & (ATM_HDR_VPI_MASK | ATM_HDR_VCI_MASK)) !=
0052         ((vcc->vpi << ATM_HDR_VPI_SHIFT) |
0053          (vcc->vci << ATM_HDR_VCI_SHIFT))) {
0054         kfree_skb(skb);
0055         return -EADDRNOTAVAIL;
0056     }
0057     if (vcc->dev->ops->send_bh)
0058         return vcc->dev->ops->send_bh(vcc, skb);
0059     return vcc->dev->ops->send(vcc, skb);
0060 }
0061
0062 int atm_init_aal0(struct atm_vcc *vcc)
0063 {
0064     vcc->push = atm_push_raw;
0065     vcc->pop = atm_pop_raw;
0066     vcc->push_oam = NULL;
0067     vcc->send = atm_send_aal0;
0068     return 0;
0069 }
0070
0071 int atm_init_aal34(struct atm_vcc *vcc)
0072 {
0073     vcc->push = atm_push_raw;
0074     vcc->pop = atm_pop_raw;
0075     vcc->push_oam = NULL;
0076     if (vcc->dev->ops->send_bh)
0077         vcc->send = vcc->dev->ops->send_bh;
0078     else
0079         vcc->send = vcc->dev->ops->send;
0080     return 0;
0081 }
0082
0083 int atm_init_aal5(struct atm_vcc *vcc)
0084 {
0085     vcc->push = atm_push_raw;
0086     vcc->pop = atm_pop_raw;
0087     vcc->push_oam = NULL;
0088     if (vcc->dev->ops->send_bh)
0089         vcc->send = vcc->dev->ops->send_bh;
0090     else
0091         vcc->send = vcc->dev->ops->send;
0092     return 0;
0093 }
0094 EXPORT_SYMBOL(atm_init_aal5);