133 lines
3.0 KiB
C
133 lines
3.0 KiB
C
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// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Generic HDLC support routines for Linux
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* HDLC Ethernet emulation support
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*
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* Copyright (C) 2002-2006 Krzysztof Halasa <khc@pm.waw.pl>
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*/
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#include <linux/errno.h>
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#include <linux/etherdevice.h>
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#include <linux/gfp.h>
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#include <linux/hdlc.h>
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#include <linux/if_arp.h>
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#include <linux/inetdevice.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/pkt_sched.h>
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#include <linux/poll.h>
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#include <linux/rtnetlink.h>
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#include <linux/skbuff.h>
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static int raw_eth_ioctl(struct net_device *dev, struct if_settings *ifs);
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static netdev_tx_t eth_tx(struct sk_buff *skb, struct net_device *dev)
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{
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int pad = ETH_ZLEN - skb->len;
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if (pad > 0) { /* Pad the frame with zeros */
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int len = skb->len;
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if (skb_tailroom(skb) < pad)
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if (pskb_expand_head(skb, 0, pad, GFP_ATOMIC)) {
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dev->stats.tx_dropped++;
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dev_kfree_skb(skb);
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return 0;
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}
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skb_put(skb, pad);
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memset(skb->data + len, 0, pad);
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}
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return dev_to_hdlc(dev)->xmit(skb, dev);
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}
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static struct hdlc_proto proto = {
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.type_trans = eth_type_trans,
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.xmit = eth_tx,
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.ioctl = raw_eth_ioctl,
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.module = THIS_MODULE,
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};
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static int raw_eth_ioctl(struct net_device *dev, struct if_settings *ifs)
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{
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raw_hdlc_proto __user *raw_s = ifs->ifs_ifsu.raw_hdlc;
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const size_t size = sizeof(raw_hdlc_proto);
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raw_hdlc_proto new_settings;
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hdlc_device *hdlc = dev_to_hdlc(dev);
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unsigned int old_qlen;
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int result;
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switch (ifs->type) {
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case IF_GET_PROTO:
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if (dev_to_hdlc(dev)->proto != &proto)
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return -EINVAL;
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ifs->type = IF_PROTO_HDLC_ETH;
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if (ifs->size < size) {
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ifs->size = size; /* data size wanted */
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return -ENOBUFS;
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}
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if (copy_to_user(raw_s, hdlc->state, size))
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return -EFAULT;
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return 0;
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case IF_PROTO_HDLC_ETH:
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if (!capable(CAP_NET_ADMIN))
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return -EPERM;
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if (dev->flags & IFF_UP)
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return -EBUSY;
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if (copy_from_user(&new_settings, raw_s, size))
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return -EFAULT;
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if (new_settings.encoding == ENCODING_DEFAULT)
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new_settings.encoding = ENCODING_NRZ;
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if (new_settings.parity == PARITY_DEFAULT)
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new_settings.parity = PARITY_CRC16_PR1_CCITT;
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result = hdlc->attach(dev, new_settings.encoding,
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new_settings.parity);
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if (result)
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return result;
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result = attach_hdlc_protocol(dev, &proto,
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sizeof(raw_hdlc_proto));
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if (result)
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return result;
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memcpy(hdlc->state, &new_settings, size);
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old_qlen = dev->tx_queue_len;
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ether_setup(dev);
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dev->tx_queue_len = old_qlen;
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dev->priv_flags &= ~IFF_TX_SKB_SHARING;
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eth_hw_addr_random(dev);
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call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
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netif_dormant_off(dev);
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return 0;
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}
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return -EINVAL;
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}
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static int __init hdlc_eth_init(void)
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{
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register_hdlc_protocol(&proto);
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return 0;
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}
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static void __exit hdlc_eth_exit(void)
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{
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unregister_hdlc_protocol(&proto);
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}
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module_init(hdlc_eth_init);
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module_exit(hdlc_eth_exit);
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MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
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MODULE_DESCRIPTION("Ethernet encapsulation support for generic HDLC");
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MODULE_LICENSE("GPL v2");
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