1 files changed, 1129 insertions, 0 deletions

diff --git a/net/econet/af_econet.c b/net/econet/af_econet.c
new file mode 100644
index 000000000000..de691e119e17
--- /dev/null
+++ b/net/econet/af_econet.c
@@ -0,0 +1,1129 @@
+/*
+ *      An implementation of the Acorn Econet and AUN protocols.
+ *      Philip Blundell <philb@gnu.org>
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/route.h>
+#include <linux/inet.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/wireless.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/inet_common.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/if_ec.h>
+#include <net/udp.h>
+#include <net/ip.h>
+#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
+#include <linux/bitops.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+static struct proto_ops econet_ops;
+static struct hlist_head econet_sklist;
+static DEFINE_RWLOCK(econet_lock);
+
+/* Since there are only 256 possible network numbers (or fewer, depends
+   how you count) it makes sense to use a simple lookup table. */
+static struct net_device *net2dev_map[256];
+
+#define EC_PORT_IP      0xd2
+
+#ifdef CONFIG_ECONET_AUNUDP
+static spinlock_t aun_queue_lock;
+static struct socket *udpsock;
+#define AUN_PORT        0x8000
+
+
+struct aunhdr
+{
+        unsigned char code;             /* AUN magic protocol byte */
+        unsigned char port;
+        unsigned char cb;
+        unsigned char pad;
+        unsigned long handle;
+};
+
+static unsigned long aun_seq;
+
+/* Queue of packets waiting to be transmitted. */
+static struct sk_buff_head aun_queue;
+static struct timer_list ab_cleanup_timer;
+
+#endif          /* CONFIG_ECONET_AUNUDP */
+
+/* Per-packet information */
+struct ec_cb
+{
+        struct sockaddr_ec sec;
+        unsigned long cookie;           /* Supplied by user. */
+#ifdef CONFIG_ECONET_AUNUDP
+        int done;
+        unsigned long seq;              /* Sequencing */
+        unsigned long timeout;          /* Timeout */
+        unsigned long start;            /* jiffies */
+#endif
+#ifdef CONFIG_ECONET_NATIVE
+        void (*sent)(struct sk_buff *, int result);
+#endif
+};
+
+static void econet_remove_socket(struct hlist_head *list, struct sock *sk)
+{
+        write_lock_bh(&econet_lock);
+        sk_del_node_init(sk);
+        write_unlock_bh(&econet_lock);
+}
+
+static void econet_insert_socket(struct hlist_head *list, struct sock *sk)
+{
+        write_lock_bh(&econet_lock);
+        sk_add_node(sk, list);
+        write_unlock_bh(&econet_lock);
+}
+
+/*
+ *      Pull a packet from our receive queue and hand it to the user.
+ *      If necessary we block.
+ */
+
+static int econet_recvmsg(struct kiocb *iocb, struct socket *sock,
+                          struct msghdr *msg, size_t len, int flags)
+{
+        struct sock *sk = sock->sk;
+        struct sk_buff *skb;
+        size_t copied;
+        int err;
+
+        msg->msg_namelen = sizeof(struct sockaddr_ec);
+
+        /*
+         *      Call the generic datagram receiver. This handles all sorts
+         *      of horrible races and re-entrancy so we can forget about it
+         *      in the protocol layers.
+         *
+         *      Now it will return ENETDOWN, if device have just gone down,
+         *      but then it will block.
+         */
+
+        skb=skb_recv_datagram(sk,flags,flags&MSG_DONTWAIT,&err);
+
+        /*
+         *      An error occurred so return it. Because skb_recv_datagram() 
+         *      handles the blocking we don't see and worry about blocking
+         *      retries.
+         */
+
+        if(skb==NULL)
+                goto out;
+
+        /*
+         *      You lose any data beyond the buffer you gave. If it worries a
+         *      user program they can ask the device for its MTU anyway.
+         */
+
+        copied = skb->len;
+        if (copied > len)
+        {
+                copied=len;
+                msg->msg_flags|=MSG_TRUNC;
+        }
+
+        /* We can't use skb_copy_datagram here */
+        err = memcpy_toiovec(msg->msg_iov, skb->data, copied);
+        if (err)
+                goto out_free;
+        sk->sk_stamp = skb->stamp;
+
+        if (msg->msg_name)
+                memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
+
+        /*
+         *      Free or return the buffer as appropriate. Again this
+         *      hides all the races and re-entrancy issues from us.
+         */
+        err = copied;
+
+out_free:
+        skb_free_datagram(sk, skb);
+out:
+        return err;
+}
+
+/*
+ *      Bind an Econet socket.
+ */
+
+static int econet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+        struct sockaddr_ec *sec = (struct sockaddr_ec *)uaddr;
+        struct sock *sk=sock->sk;
+        struct econet_sock *eo = ec_sk(sk);
+        
+        /*
+         *      Check legality
+         */
+         
+        if (addr_len < sizeof(struct sockaddr_ec) ||
+            sec->sec_family != AF_ECONET)
+                return -EINVAL;
+        
+        eo->cb      = sec->cb;
+        eo->port    = sec->port;
+        eo->station = sec->addr.station;
+        eo->net     = sec->addr.net;
+
+        return 0;
+}
+
+#if defined(CONFIG_ECONET_AUNUDP) || defined(CONFIG_ECONET_NATIVE)
+/*
+ *      Queue a transmit result for the user to be told about.
+ */
+
+static void tx_result(struct sock *sk, unsigned long cookie, int result)
+{
+        struct sk_buff *skb = alloc_skb(0, GFP_ATOMIC);
+        struct ec_cb *eb;
+        struct sockaddr_ec *sec;
+
+        if (skb == NULL)
+        {
+                printk(KERN_DEBUG "ec: memory squeeze, transmit result dropped.\n");
+                return;
+        }
+
+        eb = (struct ec_cb *)&skb->cb;
+        sec = (struct sockaddr_ec *)&eb->sec;
+        memset(sec, 0, sizeof(struct sockaddr_ec));
+        sec->cookie = cookie;
+        sec->type = ECTYPE_TRANSMIT_STATUS | result;
+        sec->sec_family = AF_ECONET;
+
+        if (sock_queue_rcv_skb(sk, skb) < 0)
+                kfree_skb(skb);
+}
+#endif
+
+#ifdef CONFIG_ECONET_NATIVE
+/*
+ *      Called by the Econet hardware driver when a packet transmit
+ *      has completed.  Tell the user.
+ */
+
+static void ec_tx_done(struct sk_buff *skb, int result)
+{
+        struct ec_cb *eb = (struct ec_cb *)&skb->cb;
+        tx_result(skb->sk, eb->cookie, result);
+}
+#endif
+
+/*
+ *      Send a packet.  We have to work out which device it's going out on
+ *      and hence whether to use real Econet or the UDP emulation.
+ */
+
+static int econet_sendmsg(struct kiocb *iocb, struct socket *sock,
+                          struct msghdr *msg, size_t len)
+{
+        struct sock *sk = sock->sk;
+        struct sockaddr_ec *saddr=(struct sockaddr_ec *)msg->msg_name;
+        struct net_device *dev;
+        struct ec_addr addr;
+        int err;
+        unsigned char port, cb;
+#if defined(CONFIG_ECONET_AUNUDP) || defined(CONFIG_ECONET_NATIVE)
+        struct sk_buff *skb;
+        struct ec_cb *eb;
+#endif
+#ifdef CONFIG_ECONET_AUNUDP
+        struct msghdr udpmsg;
+        struct iovec iov[msg->msg_iovlen+1];
+        struct aunhdr ah;
+        struct sockaddr_in udpdest;
+        __kernel_size_t size;
+        int i;
+        mm_segment_t oldfs;
+#endif
+                
+        /*
+         *      Check the flags. 
+         */
+
+        if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_CMSG_COMPAT)) 
+                return -EINVAL;
+
+        /*
+         *      Get and verify the address. 
+         */
+         
+        if (saddr == NULL) {
+                struct econet_sock *eo = ec_sk(sk);
+
+                addr.station = eo->station;
+                addr.net     = eo->net;
+                port         = eo->port;
+                cb           = eo->cb;
+        } else {
+                if (msg->msg_namelen < sizeof(struct sockaddr_ec)) 
+                        return -EINVAL;
+                addr.station = saddr->addr.station;
+                addr.net = saddr->addr.net;
+                port = saddr->port;
+                cb = saddr->cb;
+        }
+
+        /* Look for a device with the right network number. */
+        dev = net2dev_map[addr.net];
+
+        /* If not directly reachable, use some default */
+        if (dev == NULL)
+        {
+                dev = net2dev_map[0];
+                /* No interfaces at all? */
+                if (dev == NULL)
+                        return -ENETDOWN;
+        }
+
+        if (len + 15 > dev->mtu)
+                return -EMSGSIZE;
+
+        if (dev->type == ARPHRD_ECONET)
+        {
+                /* Real hardware Econet.  We're not worthy etc. */
+#ifdef CONFIG_ECONET_NATIVE
+                unsigned short proto = 0;
+
+                dev_hold(dev);
+                
+                skb = sock_alloc_send_skb(sk, len+LL_RESERVED_SPACE(dev), 
+                                          msg->msg_flags & MSG_DONTWAIT, &err);
+                if (skb==NULL)
+                        goto out_unlock;
+                
+                skb_reserve(skb, LL_RESERVED_SPACE(dev));
+                skb->nh.raw = skb->data;
+                
+                eb = (struct ec_cb *)&skb->cb;
+                
+                /* BUG: saddr may be NULL */
+                eb->cookie = saddr->cookie;
+                eb->sec = *saddr;
+                eb->sent = ec_tx_done;
+
+                if (dev->hard_header) {
+                        int res;
+                        struct ec_framehdr *fh;
+                        err = -EINVAL;
+                        res = dev->hard_header(skb, dev, ntohs(proto), 
+                                               &addr, NULL, len);
+                        /* Poke in our control byte and
+                           port number.  Hack, hack.  */
+                        fh = (struct ec_framehdr *)(skb->data);
+                        fh->cb = cb;
+                        fh->port = port;
+                        if (sock->type != SOCK_DGRAM) {
+                                skb->tail = skb->data;
+                                skb->len = 0;
+                        } else if (res < 0)
+                                goto out_free;
+                }
+                
+                /* Copy the data. Returns -EFAULT on error */
+                err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
+                skb->protocol = proto;
+                skb->dev = dev;
+                skb->priority = sk->sk_priority;
+                if (err)
+                        goto out_free;
+                
+                err = -ENETDOWN;
+                if (!(dev->flags & IFF_UP))
+                        goto out_free;
+                
+                /*
+                 *      Now send it
+                 */
+                
+                dev_queue_xmit(skb);
+                dev_put(dev);
+                return(len);
+
+        out_free:
+                kfree_skb(skb);
+        out_unlock:
+                if (dev)
+                        dev_put(dev);
+#else
+                err = -EPROTOTYPE;
+#endif
+                return err;
+        }
+
+#ifdef CONFIG_ECONET_AUNUDP
+        /* AUN virtual Econet. */
+
+        if (udpsock == NULL)
+                return -ENETDOWN;               /* No socket - can't send */
+        
+        /* Make up a UDP datagram and hand it off to some higher intellect. */
+
+        memset(&udpdest, 0, sizeof(udpdest));
+        udpdest.sin_family = AF_INET;
+        udpdest.sin_port = htons(AUN_PORT);
+
+        /* At the moment we use the stupid Acorn scheme of Econet address
+           y.x maps to IP a.b.c.x.  This should be replaced with something
+           more flexible and more aware of subnet masks.  */
+        {
+                struct in_device *idev;
+                unsigned long network = 0;
+
+                rcu_read_lock();
+                idev = __in_dev_get(dev);
+                if (idev) {
+                        if (idev->ifa_list)
+                                network = ntohl(idev->ifa_list->ifa_address) & 
+                                        0xffffff00;             /* !!! */
+                }
+                rcu_read_unlock();
+                udpdest.sin_addr.s_addr = htonl(network | addr.station);
+        }
+
+        ah.port = port;
+        ah.cb = cb & 0x7f;
+        ah.code = 2;            /* magic */
+        ah.pad = 0;
+
+        /* tack our header on the front of the iovec */
+        size = sizeof(struct aunhdr);
+        /*
+         * XXX: that is b0rken.  We can't mix userland and kernel pointers
+         * in iovec, since on a lot of platforms copy_from_user() will
+         * *not* work with the kernel and userland ones at the same time,
+         * regardless of what we do with set_fs().  And we are talking about
+         * econet-over-ethernet here, so "it's only ARM anyway" doesn't
+         * apply.  Any suggestions on fixing that code?         -- AV
+         */
+        iov[0].iov_base = (void *)&ah;
+        iov[0].iov_len = size;
+        for (i = 0; i < msg->msg_iovlen; i++) {
+                void __user *base = msg->msg_iov[i].iov_base;
+                size_t len = msg->msg_iov[i].iov_len;
+                /* Check it now since we switch to KERNEL_DS later. */
+                if (!access_ok(VERIFY_READ, base, len))
+                        return -EFAULT;
+                iov[i+1].iov_base = base;
+                iov[i+1].iov_len = len;
+                size += len;
+        }
+
+        /* Get a skbuff (no data, just holds our cb information) */
+        if ((skb = sock_alloc_send_skb(sk, 0, 
+                             msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
+                return err;
+
+        eb = (struct ec_cb *)&skb->cb;
+
+        eb->cookie = saddr->cookie;
+        eb->timeout = (5*HZ);
+        eb->start = jiffies;
+        ah.handle = aun_seq;
+        eb->seq = (aun_seq++);
+        eb->sec = *saddr;
+
+        skb_queue_tail(&aun_queue, skb);
+
+        udpmsg.msg_name = (void *)&udpdest;
+        udpmsg.msg_namelen = sizeof(udpdest);
+        udpmsg.msg_iov = &iov[0];
+        udpmsg.msg_iovlen = msg->msg_iovlen + 1;
+        udpmsg.msg_control = NULL;
+        udpmsg.msg_controllen = 0;
+        udpmsg.msg_flags=0;
+
+        oldfs = get_fs(); set_fs(KERNEL_DS);    /* More privs :-) */
+        err = sock_sendmsg(udpsock, &udpmsg, size);
+        set_fs(oldfs);
+#else
+        err = -EPROTOTYPE;
+#endif
+        return err;
+}
+
+/*
+ *      Look up the address of a socket.
+ */
+
+static int econet_getname(struct socket *sock, struct sockaddr *uaddr,
+                          int *uaddr_len, int peer)
+{
+        struct sock *sk = sock->sk;
+        struct econet_sock *eo = ec_sk(sk);
+        struct sockaddr_ec *sec = (struct sockaddr_ec *)uaddr;
+
+        if (peer)
+                return -EOPNOTSUPP;
+
+        sec->sec_family   = AF_ECONET;
+        sec->port         = eo->port;
+        sec->addr.station = eo->station;
+        sec->addr.net     = eo->net;
+
+        *uaddr_len = sizeof(*sec);
+        return 0;
+}
+
+static void econet_destroy_timer(unsigned long data)
+{
+        struct sock *sk=(struct sock *)data;
+
+        if (!atomic_read(&sk->sk_wmem_alloc) &&
+            !atomic_read(&sk->sk_rmem_alloc)) {
+                sk_free(sk);
+                return;
+        }
+
+        sk->sk_timer.expires = jiffies + 10 * HZ;
+        add_timer(&sk->sk_timer);
+        printk(KERN_DEBUG "econet socket destroy delayed\n");
+}
+
+/*
+ *      Close an econet socket.
+ */
+
+static int econet_release(struct socket *sock)
+{
+        struct sock *sk = sock->sk;
+
+        if (!sk)
+                return 0;
+
+        econet_remove_socket(&econet_sklist, sk);
+
+        /*
+         *      Now the socket is dead. No more input will appear.
+         */
+
+        sk->sk_state_change(sk);        /* It is useless. Just for sanity. */
+
+        sock->sk = NULL;
+        sk->sk_socket = NULL;
+        sock_set_flag(sk, SOCK_DEAD);
+
+        /* Purge queues */
+
+        skb_queue_purge(&sk->sk_receive_queue);
+
+        if (atomic_read(&sk->sk_rmem_alloc) ||
+            atomic_read(&sk->sk_wmem_alloc)) {
+                sk->sk_timer.data     = (unsigned long)sk;
+                sk->sk_timer.expires  = jiffies + HZ;
+                sk->sk_timer.function = econet_destroy_timer;
+                add_timer(&sk->sk_timer);
+                return 0;
+        }
+
+        sk_free(sk);
+        return 0;
+}
+
+static struct proto econet_proto = {
+        .name     = "ECONET",
+        .owner    = THIS_MODULE,
+        .obj_size = sizeof(struct econet_sock),
+};
+
+/*
+ *      Create an Econet socket
+ */
+
+static int econet_create(struct socket *sock, int protocol)
+{
+        struct sock *sk;
+        struct econet_sock *eo;
+        int err;
+
+        /* Econet only provides datagram services. */
+        if (sock->type != SOCK_DGRAM)
+                return -ESOCKTNOSUPPORT;
+
+        sock->state = SS_UNCONNECTED;
+
+        err = -ENOBUFS;
+        sk = sk_alloc(PF_ECONET, GFP_KERNEL, &econet_proto, 1);
+        if (sk == NULL)
+                goto out;
+
+        sk->sk_reuse = 1;
+        sock->ops = &econet_ops;
+        sock_init_data(sock, sk);
+
+        eo = ec_sk(sk);
+        sock_reset_flag(sk, SOCK_ZAPPED);
+        sk->sk_family = PF_ECONET;
+        eo->num = protocol;
+
+        econet_insert_socket(&econet_sklist, sk);
+        return(0);
+out:
+        return err;
+}
+
+/*
+ *      Handle Econet specific ioctls
+ */
+
+static int ec_dev_ioctl(struct socket *sock, unsigned int cmd, void __user *arg)
+{
+        struct ifreq ifr;
+        struct ec_device *edev;
+        struct net_device *dev;
+        struct sockaddr_ec *sec;
+
+        /*
+         *      Fetch the caller's info block into kernel space
+         */
+
+        if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
+                return -EFAULT;
+
+        if ((dev = dev_get_by_name(ifr.ifr_name)) == NULL) 
+                return -ENODEV;
+
+        sec = (struct sockaddr_ec *)&ifr.ifr_addr;
+
+        switch (cmd)
+        {
+        case SIOCSIFADDR:
+                edev = dev->ec_ptr;
+                if (edev == NULL)
+                {
+                        /* Magic up a new one. */
+                        edev = kmalloc(sizeof(struct ec_device), GFP_KERNEL);
+                        if (edev == NULL) {
+                                printk("af_ec: memory squeeze.\n");
+                                dev_put(dev);
+                                return -ENOMEM;
+                        }
+                        memset(edev, 0, sizeof(struct ec_device));
+                        dev->ec_ptr = edev;
+                }
+                else
+                        net2dev_map[edev->net] = NULL;
+                edev->station = sec->addr.station;
+                edev->net = sec->addr.net;
+                net2dev_map[sec->addr.net] = dev;
+                if (!net2dev_map[0])
+                        net2dev_map[0] = dev;
+                dev_put(dev);
+                return 0;
+
+        case SIOCGIFADDR:
+                edev = dev->ec_ptr;
+                if (edev == NULL)
+                {
+                        dev_put(dev);
+                        return -ENODEV;
+                }
+                memset(sec, 0, sizeof(struct sockaddr_ec));
+                sec->addr.station = edev->station;
+                sec->addr.net = edev->net;
+                sec->sec_family = AF_ECONET;
+                dev_put(dev);
+                if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
+                        return -EFAULT;
+                return 0;
+        }
+
+        dev_put(dev);
+        return -EINVAL;
+}
+
+/*
+ *      Handle generic ioctls
+ */
+
+static int econet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+        struct sock *sk = sock->sk;
+        void __user *argp = (void __user *)arg;
+
+        switch(cmd) {
+                case SIOCGSTAMP:
+                        return sock_get_timestamp(sk, argp);
+
+                case SIOCSIFADDR:
+                case SIOCGIFADDR:
+                        return ec_dev_ioctl(sock, cmd, argp);
+                        break;
+
+                default:
+                        return dev_ioctl(cmd, argp);
+        }
+        /*NOTREACHED*/
+        return 0;
+}
+
+static struct net_proto_family econet_family_ops = {
+        .family =       PF_ECONET,
+        .create =       econet_create,
+        .owner  =       THIS_MODULE,
+};
+
+static struct proto_ops SOCKOPS_WRAPPED(econet_ops) = {
+        .family =       PF_ECONET,
+        .owner =        THIS_MODULE,
+        .release =      econet_release,
+        .bind =         econet_bind,
+        .connect =      sock_no_connect,
+        .socketpair =   sock_no_socketpair,
+        .accept =       sock_no_accept,
+        .getname =      econet_getname, 
+        .poll =         datagram_poll,
+        .ioctl =        econet_ioctl,
+        .listen =       sock_no_listen,
+        .shutdown =     sock_no_shutdown,
+        .setsockopt =   sock_no_setsockopt,
+        .getsockopt =   sock_no_getsockopt,
+        .sendmsg =      econet_sendmsg,
+        .recvmsg =      econet_recvmsg,
+        .mmap =         sock_no_mmap,
+        .sendpage =     sock_no_sendpage,
+};
+
+#include <linux/smp_lock.h>
+SOCKOPS_WRAP(econet, PF_ECONET);
+
+#if defined(CONFIG_ECONET_AUNUDP) || defined(CONFIG_ECONET_NATIVE)
+/*
+ *      Find the listening socket, if any, for the given data.
+ */
+
+static struct sock *ec_listening_socket(unsigned char port, unsigned char
+                                 station, unsigned char net)
+{
+        struct sock *sk;
+        struct hlist_node *node;
+
+        sk_for_each(sk, node, &econet_sklist) {
+                struct econet_sock *opt = ec_sk(sk);
+                if ((opt->port == port || opt->port == 0) && 
+                    (opt->station == station || opt->station == 0) &&
+                    (opt->net == net || opt->net == 0))
+                        goto found;
+        }
+        sk = NULL;
+found:
+        return sk;
+}
+
+/*
+ *      Queue a received packet for a socket.
+ */
+
+static int ec_queue_packet(struct sock *sk, struct sk_buff *skb,
+                           unsigned char stn, unsigned char net,
+                           unsigned char cb, unsigned char port)
+{
+        struct ec_cb *eb = (struct ec_cb *)&skb->cb;
+        struct sockaddr_ec *sec = (struct sockaddr_ec *)&eb->sec;
+
+        memset(sec, 0, sizeof(struct sockaddr_ec));
+        sec->sec_family = AF_ECONET;
+        sec->type = ECTYPE_PACKET_RECEIVED;
+        sec->port = port;
+        sec->cb = cb;
+        sec->addr.net = net;
+        sec->addr.station = stn;
+
+        return sock_queue_rcv_skb(sk, skb);
+}
+#endif
+
+#ifdef CONFIG_ECONET_AUNUDP
+/*
+ *      Send an AUN protocol response. 
+ */
+
+static void aun_send_response(__u32 addr, unsigned long seq, int code, int cb)
+{
+        struct sockaddr_in sin = {
+                .sin_family = AF_INET,
+                .sin_port = htons(AUN_PORT),
+                .sin_addr = {.s_addr = addr}
+        };
+        struct aunhdr ah = {.code = code, .cb = cb, .handle = seq};
+        struct kvec iov = {.iov_base = (void *)&ah, .iov_len = sizeof(ah)};
+        struct msghdr udpmsg;
+        
+        udpmsg.msg_name = (void *)&sin;
+        udpmsg.msg_namelen = sizeof(sin);
+        udpmsg.msg_control = NULL;
+        udpmsg.msg_controllen = 0;
+        udpmsg.msg_flags=0;
+
+        kernel_sendmsg(udpsock, &udpmsg, &iov, 1, sizeof(ah));
+}
+
+
+/*
+ *      Handle incoming AUN packets.  Work out if anybody wants them,
+ *      and send positive or negative acknowledgements as appropriate.
+ */
+
+static void aun_incoming(struct sk_buff *skb, struct aunhdr *ah, size_t len)
+{
+        struct iphdr *ip = skb->nh.iph;
+        unsigned char stn = ntohl(ip->saddr) & 0xff;
+        struct sock *sk;
+        struct sk_buff *newskb;
+        struct ec_device *edev = skb->dev->ec_ptr;
+
+        if (! edev)
+                goto bad;
+
+        if ((sk = ec_listening_socket(ah->port, stn, edev->net)) == NULL)
+                goto bad;               /* Nobody wants it */
+
+        newskb = alloc_skb((len - sizeof(struct aunhdr) + 15) & ~15, 
+                           GFP_ATOMIC);
+        if (newskb == NULL)
+        {
+                printk(KERN_DEBUG "AUN: memory squeeze, dropping packet.\n");
+                /* Send nack and hope sender tries again */
+                goto bad;
+        }
+
+        memcpy(skb_put(newskb, len - sizeof(struct aunhdr)), (void *)(ah+1), 
+               len - sizeof(struct aunhdr));
+
+        if (ec_queue_packet(sk, newskb, stn, edev->net, ah->cb, ah->port))
+        {
+                /* Socket is bankrupt. */
+                kfree_skb(newskb);
+                goto bad;
+        }
+
+        aun_send_response(ip->saddr, ah->handle, 3, 0);
+        return;
+
+bad:
+        aun_send_response(ip->saddr, ah->handle, 4, 0);
+}
+
+/*
+ *      Handle incoming AUN transmit acknowledgements.  If the sequence
+ *      number matches something in our backlog then kill it and tell
+ *      the user.  If the remote took too long to reply then we may have
+ *      dropped the packet already.
+ */
+
+static void aun_tx_ack(unsigned long seq, int result)
+{
+        struct sk_buff *skb;
+        unsigned long flags;
+        struct ec_cb *eb;
+
+        spin_lock_irqsave(&aun_queue_lock, flags);
+        skb = skb_peek(&aun_queue);
+        while (skb && skb != (struct sk_buff *)&aun_queue)
+        {
+                struct sk_buff *newskb = skb->next;
+                eb = (struct ec_cb *)&skb->cb;
+                if (eb->seq == seq)
+                        goto foundit;
+
+                skb = newskb;
+        }
+        spin_unlock_irqrestore(&aun_queue_lock, flags);
+        printk(KERN_DEBUG "AUN: unknown sequence %ld\n", seq);
+        return;
+
+foundit:
+        tx_result(skb->sk, eb->cookie, result);
+        skb_unlink(skb);
+        spin_unlock_irqrestore(&aun_queue_lock, flags);
+        kfree_skb(skb);
+}
+
+/*
+ *      Deal with received AUN frames - sort out what type of thing it is
+ *      and hand it to the right function.
+ */
+
+static void aun_data_available(struct sock *sk, int slen)
+{
+        int err;
+        struct sk_buff *skb;
+        unsigned char *data;
+        struct aunhdr *ah;
+        struct iphdr *ip;
+        size_t len;
+
+        while ((skb = skb_recv_datagram(sk, 0, 1, &err)) == NULL) {
+                if (err == -EAGAIN) {
+                        printk(KERN_ERR "AUN: no data available?!");
+                        return;
+                }
+                printk(KERN_DEBUG "AUN: recvfrom() error %d\n", -err);
+        }
+
+        data = skb->h.raw + sizeof(struct udphdr);
+        ah = (struct aunhdr *)data;
+        len = skb->len - sizeof(struct udphdr);
+        ip = skb->nh.iph;
+
+        switch (ah->code)
+        {
+        case 2:
+                aun_incoming(skb, ah, len);
+                break;
+        case 3:
+                aun_tx_ack(ah->handle, ECTYPE_TRANSMIT_OK);
+                break;
+        case 4:
+                aun_tx_ack(ah->handle, ECTYPE_TRANSMIT_NOT_LISTENING);
+                break;
+#if 0
+                /* This isn't quite right yet. */
+        case 5:
+                aun_send_response(ip->saddr, ah->handle, 6, ah->cb);
+                break;
+#endif
+        default:
+                printk(KERN_DEBUG "unknown AUN packet (type %d)\n", data[0]);
+        }
+
+        skb_free_datagram(sk, skb);
+}
+
+/*
+ *      Called by the timer to manage the AUN transmit queue.  If a packet
+ *      was sent to a dead or nonexistent host then we will never get an
+ *      acknowledgement back.  After a few seconds we need to spot this and
+ *      drop the packet.
+ */
+
+static void ab_cleanup(unsigned long h)
+{
+        struct sk_buff *skb;
+        unsigned long flags;
+
+        spin_lock_irqsave(&aun_queue_lock, flags);
+        skb = skb_peek(&aun_queue);
+        while (skb && skb != (struct sk_buff *)&aun_queue)
+        {
+                struct sk_buff *newskb = skb->next;
+                struct ec_cb *eb = (struct ec_cb *)&skb->cb;
+                if ((jiffies - eb->start) > eb->timeout)
+                {
+                        tx_result(skb->sk, eb->cookie, 
+                                  ECTYPE_TRANSMIT_NOT_PRESENT);
+                        skb_unlink(skb);
+                        kfree_skb(skb);
+                }
+                skb = newskb;
+        }
+        spin_unlock_irqrestore(&aun_queue_lock, flags);
+
+        mod_timer(&ab_cleanup_timer, jiffies + (HZ*2));
+}
+
+static int __init aun_udp_initialise(void)
+{
+        int error;
+        struct sockaddr_in sin;
+
+        skb_queue_head_init(&aun_queue);
+        spin_lock_init(&aun_queue_lock);
+        init_timer(&ab_cleanup_timer);
+        ab_cleanup_timer.expires = jiffies + (HZ*2);
+        ab_cleanup_timer.function = ab_cleanup;
+        add_timer(&ab_cleanup_timer);
+
+        memset(&sin, 0, sizeof(sin));
+        sin.sin_port = htons(AUN_PORT);
+
+        /* We can count ourselves lucky Acorn machines are too dim to
+           speak IPv6. :-) */
+        if ((error = sock_create_kern(PF_INET, SOCK_DGRAM, 0, &udpsock)) < 0)
+        {
+                printk("AUN: socket error %d\n", -error);
+                return error;
+        }
+        
+        udpsock->sk->sk_reuse = 1;
+        udpsock->sk->sk_allocation = GFP_ATOMIC; /* we're going to call it
+                                                    from interrupts */
+        
+        error = udpsock->ops->bind(udpsock, (struct sockaddr *)&sin,
+                                sizeof(sin));
+        if (error < 0)
+        {
+                printk("AUN: bind error %d\n", -error);
+                goto release;
+        }
+
+        udpsock->sk->sk_data_ready = aun_data_available;
+
+        return 0;
+
+release:
+        sock_release(udpsock);
+        udpsock = NULL;
+        return error;
+}
+#endif
+
+#ifdef CONFIG_ECONET_NATIVE
+
+/*
+ *      Receive an Econet frame from a device.
+ */
+
+static int econet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt)
+{
+        struct ec_framehdr *hdr;
+        struct sock *sk;
+        struct ec_device *edev = dev->ec_ptr;
+
+        if (skb->pkt_type == PACKET_OTHERHOST)
+                goto drop;
+
+        if (!edev)
+                goto drop;
+
+        if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
+                return NET_RX_DROP;
+
+        if (!pskb_may_pull(skb, sizeof(struct ec_framehdr)))
+                goto drop;
+
+        hdr = (struct ec_framehdr *) skb->data;
+
+        /* First check for encapsulated IP */
+        if (hdr->port == EC_PORT_IP) {
+                skb->protocol = htons(ETH_P_IP);
+                skb_pull(skb, sizeof(struct ec_framehdr));
+                netif_rx(skb);
+                return 0;
+        }
+
+        sk = ec_listening_socket(hdr->port, hdr->src_stn, hdr->src_net);
+        if (!sk)
+                goto drop;
+
+        if (ec_queue_packet(sk, skb, edev->net, hdr->src_stn, hdr->cb,
+                            hdr->port))
+                goto drop;
+
+        return 0;
+
+drop:
+        kfree_skb(skb);
+        return NET_RX_DROP;
+}
+
+static struct packet_type econet_packet_type = {
+        .type =         __constant_htons(ETH_P_ECONET),
+        .func =         econet_rcv,
+};
+
+static void econet_hw_initialise(void)
+{
+        dev_add_pack(&econet_packet_type);
+}
+
+#endif
+
+static int econet_notifier(struct notifier_block *this, unsigned long msg, void *data)
+{
+        struct net_device *dev = (struct net_device *)data;
+        struct ec_device *edev;
+
+        switch (msg) {
+        case NETDEV_UNREGISTER:
+                /* A device has gone down - kill any data we hold for it. */
+                edev = dev->ec_ptr;
+                if (edev)
+                {
+                        if (net2dev_map[0] == dev)
+                                net2dev_map[0] = NULL;
+                        net2dev_map[edev->net] = NULL;
+                        kfree(edev);
+                        dev->ec_ptr = NULL;
+                }
+                break;
+        }
+
+        return NOTIFY_DONE;
+}
+
+static struct notifier_block econet_netdev_notifier = {
+        .notifier_call =econet_notifier,
+};
+
+static void __exit econet_proto_exit(void)
+{
+#ifdef CONFIG_ECONET_AUNUDP
+        del_timer(&ab_cleanup_timer);
+        if (udpsock)
+                sock_release(udpsock);
+#endif
+        unregister_netdevice_notifier(&econet_netdev_notifier);
+        sock_unregister(econet_family_ops.family);
+        proto_unregister(&econet_proto);
+}
+
+static int __init econet_proto_init(void)
+{
+        int err = proto_register(&econet_proto, 0);
+
+        if (err != 0)
+                goto out;
+        sock_register(&econet_family_ops);
+#ifdef CONFIG_ECONET_AUNUDP
+        spin_lock_init(&aun_queue_lock);
+        aun_udp_initialise();
+#endif
+#ifdef CONFIG_ECONET_NATIVE
+        econet_hw_initialise();
+#endif
+        register_netdevice_notifier(&econet_netdev_notifier);
+out:
+        return err;
+}
+
+module_init(econet_proto_init);
+module_exit(econet_proto_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_ECONET);