133 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			133 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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|  * This program is free software; you can redistribute it and/or modify it
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|  * under the terms of version 2 of the GNU General Public License
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|  * as published by the Free Software Foundation.
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|  */
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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/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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| #include <linux/slab.h>
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| 
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| static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr);
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| 
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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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| 
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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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| 
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| 
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| static int raw_eth_ioctl(struct net_device *dev, struct ifreq *ifr)
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| {
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| 	raw_hdlc_proto __user *raw_s = ifr->ifr_settings.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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| 	int result, old_qlen;
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| 
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| 	switch (ifr->ifr_settings.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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| 		ifr->ifr_settings.type = IF_PROTO_HDLC_ETH;
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| 		if (ifr->ifr_settings.size < size) {
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| 			ifr->ifr_settings.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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| 
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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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| 
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| 		if (dev->flags & IFF_UP)
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| 			return -EBUSY;
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| 
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| 		if (copy_from_user(&new_settings, raw_s, size))
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| 			return -EFAULT;
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| 
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| 		if (new_settings.encoding == ENCODING_DEFAULT)
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| 			new_settings.encoding = ENCODING_NRZ;
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| 
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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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| 
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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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| 
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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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| 		random_ether_addr(dev->dev_addr);
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| 		netif_dormant_off(dev);
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| 		return 0;
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| 	}
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| 
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| 	return -EINVAL;
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| }
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| 
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| 
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| static int __init mod_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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| 
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| 
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| 
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| static void __exit mod_exit(void)
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| {
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| 	unregister_hdlc_protocol(&proto);
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| }
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| 
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| 
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| module_init(mod_init);
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| module_exit(mod_exit);
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| 
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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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