410 строки
9.6 KiB
C
410 строки
9.6 KiB
C
/*
|
|
* Generic HDLC support routines for Linux
|
|
* Cisco HDLC support
|
|
*
|
|
* Copyright (C) 2000 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of version 2 of the GNU General Public License
|
|
* as published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/hdlc.h>
|
|
#include <linux/if_arp.h>
|
|
#include <linux/inetdevice.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pkt_sched.h>
|
|
#include <linux/poll.h>
|
|
#include <linux/rtnetlink.h>
|
|
#include <linux/skbuff.h>
|
|
|
|
#undef DEBUG_HARD_HEADER
|
|
|
|
#define CISCO_MULTICAST 0x8F /* Cisco multicast address */
|
|
#define CISCO_UNICAST 0x0F /* Cisco unicast address */
|
|
#define CISCO_KEEPALIVE 0x8035 /* Cisco keepalive protocol */
|
|
#define CISCO_SYS_INFO 0x2000 /* Cisco interface/system info */
|
|
#define CISCO_ADDR_REQ 0 /* Cisco address request */
|
|
#define CISCO_ADDR_REPLY 1 /* Cisco address reply */
|
|
#define CISCO_KEEPALIVE_REQ 2 /* Cisco keepalive request */
|
|
|
|
|
|
struct hdlc_header {
|
|
u8 address;
|
|
u8 control;
|
|
__be16 protocol;
|
|
}__packed;
|
|
|
|
|
|
struct cisco_packet {
|
|
__be32 type; /* code */
|
|
__be32 par1;
|
|
__be32 par2;
|
|
__be16 rel; /* reliability */
|
|
__be32 time;
|
|
}__packed;
|
|
#define CISCO_PACKET_LEN 18
|
|
#define CISCO_BIG_PACKET_LEN 20
|
|
|
|
|
|
struct cisco_state {
|
|
cisco_proto settings;
|
|
|
|
struct timer_list timer;
|
|
spinlock_t lock;
|
|
unsigned long last_poll;
|
|
int up;
|
|
u32 txseq; /* TX sequence number, 0 = none */
|
|
u32 rxseq; /* RX sequence number */
|
|
};
|
|
|
|
|
|
static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr);
|
|
|
|
|
|
static inline struct cisco_state* state(hdlc_device *hdlc)
|
|
{
|
|
return (struct cisco_state *)hdlc->state;
|
|
}
|
|
|
|
|
|
static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev,
|
|
u16 type, const void *daddr, const void *saddr,
|
|
unsigned int len)
|
|
{
|
|
struct hdlc_header *data;
|
|
#ifdef DEBUG_HARD_HEADER
|
|
printk(KERN_DEBUG "%s: cisco_hard_header called\n", dev->name);
|
|
#endif
|
|
|
|
skb_push(skb, sizeof(struct hdlc_header));
|
|
data = (struct hdlc_header*)skb->data;
|
|
if (type == CISCO_KEEPALIVE)
|
|
data->address = CISCO_MULTICAST;
|
|
else
|
|
data->address = CISCO_UNICAST;
|
|
data->control = 0;
|
|
data->protocol = htons(type);
|
|
|
|
return sizeof(struct hdlc_header);
|
|
}
|
|
|
|
|
|
|
|
static void cisco_keepalive_send(struct net_device *dev, u32 type,
|
|
__be32 par1, __be32 par2)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct cisco_packet *data;
|
|
|
|
skb = dev_alloc_skb(sizeof(struct hdlc_header) +
|
|
sizeof(struct cisco_packet));
|
|
if (!skb) {
|
|
netdev_warn(dev, "Memory squeeze on cisco_keepalive_send()\n");
|
|
return;
|
|
}
|
|
skb_reserve(skb, 4);
|
|
cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0);
|
|
data = (struct cisco_packet*)(skb->data + 4);
|
|
|
|
data->type = htonl(type);
|
|
data->par1 = par1;
|
|
data->par2 = par2;
|
|
data->rel = cpu_to_be16(0xFFFF);
|
|
/* we will need do_div here if 1000 % HZ != 0 */
|
|
data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ));
|
|
|
|
skb_put(skb, sizeof(struct cisco_packet));
|
|
skb->priority = TC_PRIO_CONTROL;
|
|
skb->dev = dev;
|
|
skb_reset_network_header(skb);
|
|
|
|
dev_queue_xmit(skb);
|
|
}
|
|
|
|
|
|
|
|
static __be16 cisco_type_trans(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct hdlc_header *data = (struct hdlc_header*)skb->data;
|
|
|
|
if (skb->len < sizeof(struct hdlc_header))
|
|
return cpu_to_be16(ETH_P_HDLC);
|
|
|
|
if (data->address != CISCO_MULTICAST &&
|
|
data->address != CISCO_UNICAST)
|
|
return cpu_to_be16(ETH_P_HDLC);
|
|
|
|
switch (data->protocol) {
|
|
case cpu_to_be16(ETH_P_IP):
|
|
case cpu_to_be16(ETH_P_IPX):
|
|
case cpu_to_be16(ETH_P_IPV6):
|
|
skb_pull(skb, sizeof(struct hdlc_header));
|
|
return data->protocol;
|
|
default:
|
|
return cpu_to_be16(ETH_P_HDLC);
|
|
}
|
|
}
|
|
|
|
|
|
static int cisco_rx(struct sk_buff *skb)
|
|
{
|
|
struct net_device *dev = skb->dev;
|
|
hdlc_device *hdlc = dev_to_hdlc(dev);
|
|
struct cisco_state *st = state(hdlc);
|
|
struct hdlc_header *data = (struct hdlc_header*)skb->data;
|
|
struct cisco_packet *cisco_data;
|
|
struct in_device *in_dev;
|
|
__be32 addr, mask;
|
|
u32 ack;
|
|
|
|
if (skb->len < sizeof(struct hdlc_header))
|
|
goto rx_error;
|
|
|
|
if (data->address != CISCO_MULTICAST &&
|
|
data->address != CISCO_UNICAST)
|
|
goto rx_error;
|
|
|
|
switch (ntohs(data->protocol)) {
|
|
case CISCO_SYS_INFO:
|
|
/* Packet is not needed, drop it. */
|
|
dev_kfree_skb_any(skb);
|
|
return NET_RX_SUCCESS;
|
|
|
|
case CISCO_KEEPALIVE:
|
|
if ((skb->len != sizeof(struct hdlc_header) +
|
|
CISCO_PACKET_LEN) &&
|
|
(skb->len != sizeof(struct hdlc_header) +
|
|
CISCO_BIG_PACKET_LEN)) {
|
|
netdev_info(dev, "Invalid length of Cisco control packet (%d bytes)\n",
|
|
skb->len);
|
|
goto rx_error;
|
|
}
|
|
|
|
cisco_data = (struct cisco_packet*)(skb->data + sizeof
|
|
(struct hdlc_header));
|
|
|
|
switch (ntohl (cisco_data->type)) {
|
|
case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */
|
|
rcu_read_lock();
|
|
in_dev = __in_dev_get_rcu(dev);
|
|
addr = 0;
|
|
mask = ~cpu_to_be32(0); /* is the mask correct? */
|
|
|
|
if (in_dev != NULL) {
|
|
struct in_ifaddr **ifap = &in_dev->ifa_list;
|
|
|
|
while (*ifap != NULL) {
|
|
if (strcmp(dev->name,
|
|
(*ifap)->ifa_label) == 0) {
|
|
addr = (*ifap)->ifa_local;
|
|
mask = (*ifap)->ifa_mask;
|
|
break;
|
|
}
|
|
ifap = &(*ifap)->ifa_next;
|
|
}
|
|
|
|
cisco_keepalive_send(dev, CISCO_ADDR_REPLY,
|
|
addr, mask);
|
|
}
|
|
rcu_read_unlock();
|
|
dev_kfree_skb_any(skb);
|
|
return NET_RX_SUCCESS;
|
|
|
|
case CISCO_ADDR_REPLY:
|
|
netdev_info(dev, "Unexpected Cisco IP address reply\n");
|
|
goto rx_error;
|
|
|
|
case CISCO_KEEPALIVE_REQ:
|
|
spin_lock(&st->lock);
|
|
st->rxseq = ntohl(cisco_data->par1);
|
|
ack = ntohl(cisco_data->par2);
|
|
if (ack && (ack == st->txseq ||
|
|
/* our current REQ may be in transit */
|
|
ack == st->txseq - 1)) {
|
|
st->last_poll = jiffies;
|
|
if (!st->up) {
|
|
u32 sec, min, hrs, days;
|
|
sec = ntohl(cisco_data->time) / 1000;
|
|
min = sec / 60; sec -= min * 60;
|
|
hrs = min / 60; min -= hrs * 60;
|
|
days = hrs / 24; hrs -= days * 24;
|
|
netdev_info(dev, "Link up (peer uptime %ud%uh%um%us)\n",
|
|
days, hrs, min, sec);
|
|
netif_dormant_off(dev);
|
|
st->up = 1;
|
|
}
|
|
}
|
|
spin_unlock(&st->lock);
|
|
|
|
dev_kfree_skb_any(skb);
|
|
return NET_RX_SUCCESS;
|
|
} /* switch (keepalive type) */
|
|
} /* switch (protocol) */
|
|
|
|
netdev_info(dev, "Unsupported protocol %x\n", ntohs(data->protocol));
|
|
dev_kfree_skb_any(skb);
|
|
return NET_RX_DROP;
|
|
|
|
rx_error:
|
|
dev->stats.rx_errors++; /* Mark error */
|
|
dev_kfree_skb_any(skb);
|
|
return NET_RX_DROP;
|
|
}
|
|
|
|
|
|
|
|
static void cisco_timer(unsigned long arg)
|
|
{
|
|
struct net_device *dev = (struct net_device *)arg;
|
|
hdlc_device *hdlc = dev_to_hdlc(dev);
|
|
struct cisco_state *st = state(hdlc);
|
|
|
|
spin_lock(&st->lock);
|
|
if (st->up &&
|
|
time_after(jiffies, st->last_poll + st->settings.timeout * HZ)) {
|
|
st->up = 0;
|
|
netdev_info(dev, "Link down\n");
|
|
netif_dormant_on(dev);
|
|
}
|
|
|
|
cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, htonl(++st->txseq),
|
|
htonl(st->rxseq));
|
|
spin_unlock(&st->lock);
|
|
|
|
st->timer.expires = jiffies + st->settings.interval * HZ;
|
|
st->timer.function = cisco_timer;
|
|
st->timer.data = arg;
|
|
add_timer(&st->timer);
|
|
}
|
|
|
|
|
|
|
|
static void cisco_start(struct net_device *dev)
|
|
{
|
|
hdlc_device *hdlc = dev_to_hdlc(dev);
|
|
struct cisco_state *st = state(hdlc);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&st->lock, flags);
|
|
st->up = st->txseq = st->rxseq = 0;
|
|
spin_unlock_irqrestore(&st->lock, flags);
|
|
|
|
init_timer(&st->timer);
|
|
st->timer.expires = jiffies + HZ; /* First poll after 1 s */
|
|
st->timer.function = cisco_timer;
|
|
st->timer.data = (unsigned long)dev;
|
|
add_timer(&st->timer);
|
|
}
|
|
|
|
|
|
|
|
static void cisco_stop(struct net_device *dev)
|
|
{
|
|
hdlc_device *hdlc = dev_to_hdlc(dev);
|
|
struct cisco_state *st = state(hdlc);
|
|
unsigned long flags;
|
|
|
|
del_timer_sync(&st->timer);
|
|
|
|
spin_lock_irqsave(&st->lock, flags);
|
|
netif_dormant_on(dev);
|
|
st->up = st->txseq = 0;
|
|
spin_unlock_irqrestore(&st->lock, flags);
|
|
}
|
|
|
|
|
|
static struct hdlc_proto proto = {
|
|
.start = cisco_start,
|
|
.stop = cisco_stop,
|
|
.type_trans = cisco_type_trans,
|
|
.ioctl = cisco_ioctl,
|
|
.netif_rx = cisco_rx,
|
|
.module = THIS_MODULE,
|
|
};
|
|
|
|
static const struct header_ops cisco_header_ops = {
|
|
.create = cisco_hard_header,
|
|
};
|
|
|
|
static int cisco_ioctl(struct net_device *dev, struct ifreq *ifr)
|
|
{
|
|
cisco_proto __user *cisco_s = ifr->ifr_settings.ifs_ifsu.cisco;
|
|
const size_t size = sizeof(cisco_proto);
|
|
cisco_proto new_settings;
|
|
hdlc_device *hdlc = dev_to_hdlc(dev);
|
|
int result;
|
|
|
|
switch (ifr->ifr_settings.type) {
|
|
case IF_GET_PROTO:
|
|
if (dev_to_hdlc(dev)->proto != &proto)
|
|
return -EINVAL;
|
|
ifr->ifr_settings.type = IF_PROTO_CISCO;
|
|
if (ifr->ifr_settings.size < size) {
|
|
ifr->ifr_settings.size = size; /* data size wanted */
|
|
return -ENOBUFS;
|
|
}
|
|
if (copy_to_user(cisco_s, &state(hdlc)->settings, size))
|
|
return -EFAULT;
|
|
return 0;
|
|
|
|
case IF_PROTO_CISCO:
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (dev->flags & IFF_UP)
|
|
return -EBUSY;
|
|
|
|
if (copy_from_user(&new_settings, cisco_s, size))
|
|
return -EFAULT;
|
|
|
|
if (new_settings.interval < 1 ||
|
|
new_settings.timeout < 2)
|
|
return -EINVAL;
|
|
|
|
result = hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
|
|
if (result)
|
|
return result;
|
|
|
|
result = attach_hdlc_protocol(dev, &proto,
|
|
sizeof(struct cisco_state));
|
|
if (result)
|
|
return result;
|
|
|
|
memcpy(&state(hdlc)->settings, &new_settings, size);
|
|
spin_lock_init(&state(hdlc)->lock);
|
|
dev->header_ops = &cisco_header_ops;
|
|
dev->type = ARPHRD_CISCO;
|
|
call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
|
|
netif_dormant_on(dev);
|
|
return 0;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
|
|
static int __init mod_init(void)
|
|
{
|
|
register_hdlc_protocol(&proto);
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
static void __exit mod_exit(void)
|
|
{
|
|
unregister_hdlc_protocol(&proto);
|
|
}
|
|
|
|
|
|
module_init(mod_init);
|
|
module_exit(mod_exit);
|
|
|
|
MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
|
|
MODULE_DESCRIPTION("Cisco HDLC protocol support for generic HDLC");
|
|
MODULE_LICENSE("GPL v2");
|