Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 609 insertions, 0 deletions

diff --git a/drivers/net/hamradio/bpqether.c b/drivers/net/hamradio/bpqether.c
new file mode 100644
index 000000000..83a16d10e
--- /dev/null
+++ b/drivers/net/hamradio/bpqether.c
@@ -0,0 +1,609 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	G8BPQ compatible "AX.25 via ethernet" driver release 004
+ *
+ *	This code REQUIRES 2.0.0 or higher/ NET3.029
+ *
+ *	This is a "pseudo" network driver to allow AX.25 over Ethernet
+ *	using G8BPQ encapsulation. It has been extracted from the protocol
+ *	implementation because
+ *
+ *		- things got unreadable within the protocol stack
+ *		- to cure the protocol stack from "feature-ism"
+ *		- a protocol implementation shouldn't need to know on
+ *		  which hardware it is running
+ *		- user-level programs like the AX.25 utilities shouldn't
+ *		  need to know about the hardware.
+ *		- IP over ethernet encapsulated AX.25 was impossible
+ *		- rxecho.c did not work
+ *		- to have room for extensions
+ *		- it just deserves to "live" as an own driver
+ *
+ *	This driver can use any ethernet destination address, and can be
+ *	limited to accept frames from one dedicated ethernet card only.
+ *
+ *	Note that the driver sets up the BPQ devices automagically on
+ *	startup or (if started before the "insmod" of an ethernet device)
+ *	on "ifconfig up". It hopefully will remove the BPQ on "rmmod"ing
+ *	the ethernet device (in fact: as soon as another ethernet or bpq
+ *	device gets "ifconfig"ured).
+ *
+ *	I have heard that several people are thinking of experiments
+ *	with highspeed packet radio using existing ethernet cards.
+ *	Well, this driver is prepared for this purpose, just add
+ *	your tx key control and a txdelay / tailtime algorithm,
+ *	probably some buffering, and /voila/...
+ *
+ *	History
+ *	BPQ   001	Joerg(DL1BKE)		Extracted BPQ code from AX.25
+ *						protocol stack and added my own
+ *						yet existing patches
+ *	BPQ   002	Joerg(DL1BKE)		Scan network device list on
+ *						startup.
+ *	BPQ   003	Joerg(DL1BKE)		Ethernet destination address
+ *						and accepted source address
+ *						can be configured by an ioctl()
+ *						call.
+ *						Fixed to match Linux networking
+ *						changes - 2.1.15.
+ *	BPQ   004	Joerg(DL1BKE)		Fixed to not lock up on ifconfig.
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/uaccess.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/stat.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rtnetlink.h>
+
+#include <net/ip.h>
+#include <net/arp.h>
+#include <net/net_namespace.h>
+
+#include <linux/bpqether.h>
+
+static const char banner[] __initconst = KERN_INFO \
+	"AX.25: bpqether driver version 004\n";
+
+static int bpq_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);
+static int bpq_device_event(struct notifier_block *, unsigned long, void *);
+
+static struct packet_type bpq_packet_type __read_mostly = {
+	.type	= cpu_to_be16(ETH_P_BPQ),
+	.func	= bpq_rcv,
+};
+
+static struct notifier_block bpq_dev_notifier = {
+	.notifier_call = bpq_device_event,
+};
+
+
+struct bpqdev {
+	struct list_head bpq_list;	/* list of bpq devices chain */
+	struct net_device *ethdev;	/* link to ethernet device */
+	struct net_device *axdev;	/* bpq device (bpq#) */
+	char   dest_addr[6];		/* ether destination address */
+	char   acpt_addr[6];		/* accept ether frames from this address only */
+};
+
+static LIST_HEAD(bpq_devices);
+
+/*
+ * bpqether network devices are paired with ethernet devices below them, so
+ * form a special "super class" of normal ethernet devices; split their locks
+ * off into a separate class since they always nest.
+ */
+static struct lock_class_key bpq_netdev_xmit_lock_key;
+static struct lock_class_key bpq_netdev_addr_lock_key;
+
+static void bpq_set_lockdep_class_one(struct net_device *dev,
+				      struct netdev_queue *txq,
+				      void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &bpq_netdev_xmit_lock_key);
+}
+
+static void bpq_set_lockdep_class(struct net_device *dev)
+{
+	lockdep_set_class(&dev->addr_list_lock, &bpq_netdev_addr_lock_key);
+	netdev_for_each_tx_queue(dev, bpq_set_lockdep_class_one, NULL);
+}
+
+/* ------------------------------------------------------------------------ */
+
+
+/*
+ *	Get the ethernet device for a BPQ device
+ */
+static inline struct net_device *bpq_get_ether_dev(struct net_device *dev)
+{
+	struct bpqdev *bpq = netdev_priv(dev);
+
+	return bpq ? bpq->ethdev : NULL;
+}
+
+/*
+ *	Get the BPQ device for the ethernet device
+ */
+static inline struct net_device *bpq_get_ax25_dev(struct net_device *dev)
+{
+	struct bpqdev *bpq;
+
+	list_for_each_entry_rcu(bpq, &bpq_devices, bpq_list,
+				lockdep_rtnl_is_held()) {
+		if (bpq->ethdev == dev)
+			return bpq->axdev;
+	}
+	return NULL;
+}
+
+static inline int dev_is_ethdev(struct net_device *dev)
+{
+	return dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5);
+}
+
+/* ------------------------------------------------------------------------ */
+
+
+/*
+ *	Receive an AX.25 frame via an ethernet interface.
+ */
+static int bpq_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *ptype, struct net_device *orig_dev)
+{
+	int len;
+	char * ptr;
+	struct ethhdr *eth;
+	struct bpqdev *bpq;
+
+	if (!net_eq(dev_net(dev), &init_net))
+		goto drop;
+
+	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
+		return NET_RX_DROP;
+
+	if (!pskb_may_pull(skb, sizeof(struct ethhdr)))
+		goto drop;
+
+	rcu_read_lock();
+	dev = bpq_get_ax25_dev(dev);
+
+	if (dev == NULL || !netif_running(dev)) 
+		goto drop_unlock;
+
+	/*
+	 * if we want to accept frames from just one ethernet device
+	 * we check the source address of the sender.
+	 */
+
+	bpq = netdev_priv(dev);
+
+	eth = eth_hdr(skb);
+
+	if (!(bpq->acpt_addr[0] & 0x01) &&
+	    !ether_addr_equal(eth->h_source, bpq->acpt_addr))
+		goto drop_unlock;
+
+	if (skb_cow(skb, sizeof(struct ethhdr)))
+		goto drop_unlock;
+
+	len = skb->data[0] + skb->data[1] * 256 - 5;
+
+	skb_pull(skb, 2);	/* Remove the length bytes */
+	skb_trim(skb, len);	/* Set the length of the data */
+
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += len;
+
+	ptr = skb_push(skb, 1);
+	*ptr = 0;
+
+	skb->protocol = ax25_type_trans(skb, dev);
+	netif_rx(skb);
+unlock:
+
+	rcu_read_unlock();
+
+	return 0;
+drop_unlock:
+	kfree_skb(skb);
+	goto unlock;
+
+drop:
+	kfree_skb(skb);
+	return 0;
+}
+
+/*
+ * 	Send an AX.25 frame via an ethernet interface
+ */
+static netdev_tx_t bpq_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	unsigned char *ptr;
+	struct bpqdev *bpq;
+	struct net_device *orig_dev;
+	int size;
+
+	if (skb->protocol == htons(ETH_P_IP))
+		return ax25_ip_xmit(skb);
+
+	/*
+	 * Just to be *really* sure not to send anything if the interface
+	 * is down, the ethernet device may have gone.
+	 */
+	if (!netif_running(dev)) {
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	skb_pull(skb, 1);			/* Drop KISS byte */
+	size = skb->len;
+
+	/*
+	 * We're about to mess with the skb which may still shared with the
+	 * generic networking code so unshare and ensure it's got enough
+	 * space for the BPQ headers.
+	 */
+	if (skb_cow(skb, AX25_BPQ_HEADER_LEN)) {
+		if (net_ratelimit())
+			pr_err("bpqether: out of memory\n");
+		kfree_skb(skb);
+
+		return NETDEV_TX_OK;
+	}
+
+	ptr = skb_push(skb, 2);			/* Make space for length */
+
+	*ptr++ = (size + 5) % 256;
+	*ptr++ = (size + 5) / 256;
+
+	bpq = netdev_priv(dev);
+
+	orig_dev = dev;
+	if ((dev = bpq_get_ether_dev(dev)) == NULL) {
+		orig_dev->stats.tx_dropped++;
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	skb->protocol = ax25_type_trans(skb, dev);
+	skb_reset_network_header(skb);
+	dev_hard_header(skb, dev, ETH_P_BPQ, bpq->dest_addr, NULL, 0);
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes+=skb->len;
+  
+	dev_queue_xmit(skb);
+	netif_wake_queue(dev);
+	return NETDEV_TX_OK;
+}
+
+/*
+ *	Set AX.25 callsign
+ */
+static int bpq_set_mac_address(struct net_device *dev, void *addr)
+{
+    struct sockaddr *sa = (struct sockaddr *)addr;
+
+    dev_addr_set(dev, sa->sa_data);
+
+    return 0;
+}
+
+/*	Ioctl commands
+ *
+ *		SIOCSBPQETHOPT		reserved for enhancements
+ *		SIOCSBPQETHADDR		set the destination and accepted
+ *					source ethernet address (broadcast
+ *					or multicast: accept all)
+ */
+static int bpq_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
+			      void __user *data, int cmd)
+{
+	struct bpq_ethaddr __user *ethaddr = data;
+	struct bpqdev *bpq = netdev_priv(dev);
+	struct bpq_req req;
+
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
+	switch (cmd) {
+		case SIOCSBPQETHOPT:
+			if (copy_from_user(&req, data, sizeof(struct bpq_req)))
+				return -EFAULT;
+			switch (req.cmd) {
+				case SIOCGBPQETHPARAM:
+				case SIOCSBPQETHPARAM:
+				default:
+					return -EINVAL;
+			}
+
+			break;
+
+		case SIOCSBPQETHADDR:
+			if (copy_from_user(bpq->dest_addr, ethaddr->destination, ETH_ALEN))
+				return -EFAULT;
+			if (copy_from_user(bpq->acpt_addr, ethaddr->accept, ETH_ALEN))
+				return -EFAULT;
+			break;
+
+		default:
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * open/close a device
+ */
+static int bpq_open(struct net_device *dev)
+{
+	netif_start_queue(dev);
+	return 0;
+}
+
+static int bpq_close(struct net_device *dev)
+{
+	netif_stop_queue(dev);
+	return 0;
+}
+
+
+/* ------------------------------------------------------------------------ */
+
+#ifdef CONFIG_PROC_FS
+/*
+ *	Proc filesystem
+ */
+static void *bpq_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(RCU)
+{
+	int i = 1;
+	struct bpqdev *bpqdev;
+
+	rcu_read_lock();
+
+	if (*pos == 0)
+		return SEQ_START_TOKEN;
+	
+	list_for_each_entry_rcu(bpqdev, &bpq_devices, bpq_list) {
+		if (i == *pos)
+			return bpqdev;
+	}
+	return NULL;
+}
+
+static void *bpq_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct list_head *p;
+	struct bpqdev *bpqdev = v;
+
+	++*pos;
+
+	if (v == SEQ_START_TOKEN)
+		p = rcu_dereference(list_next_rcu(&bpq_devices));
+	else
+		p = rcu_dereference(list_next_rcu(&bpqdev->bpq_list));
+
+	return (p == &bpq_devices) ? NULL 
+		: list_entry(p, struct bpqdev, bpq_list);
+}
+
+static void bpq_seq_stop(struct seq_file *seq, void *v)
+	__releases(RCU)
+{
+	rcu_read_unlock();
+}
+
+
+static int bpq_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq, 
+			 "dev   ether      destination        accept from\n");
+	else {
+		const struct bpqdev *bpqdev = v;
+
+		seq_printf(seq, "%-5s %-10s %pM  ",
+			bpqdev->axdev->name, bpqdev->ethdev->name,
+			bpqdev->dest_addr);
+
+		if (is_multicast_ether_addr(bpqdev->acpt_addr))
+			seq_printf(seq, "*\n");
+		else
+			seq_printf(seq, "%pM\n", bpqdev->acpt_addr);
+
+	}
+	return 0;
+}
+
+static const struct seq_operations bpq_seqops = {
+	.start = bpq_seq_start,
+	.next = bpq_seq_next,
+	.stop = bpq_seq_stop,
+	.show = bpq_seq_show,
+};
+#endif
+/* ------------------------------------------------------------------------ */
+
+static const struct net_device_ops bpq_netdev_ops = {
+	.ndo_open	     = bpq_open,
+	.ndo_stop	     = bpq_close,
+	.ndo_start_xmit	     = bpq_xmit,
+	.ndo_set_mac_address = bpq_set_mac_address,
+	.ndo_siocdevprivate  = bpq_siocdevprivate,
+};
+
+static void bpq_setup(struct net_device *dev)
+{
+	dev->netdev_ops	     = &bpq_netdev_ops;
+	dev->needs_free_netdev = true;
+
+	dev->flags      = 0;
+	dev->features	= NETIF_F_LLTX;	/* Allow recursion */
+
+#if IS_ENABLED(CONFIG_AX25)
+	dev->header_ops      = &ax25_header_ops;
+#endif
+
+	dev->type            = ARPHRD_AX25;
+	dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
+	dev->mtu             = AX25_DEF_PACLEN;
+	dev->addr_len        = AX25_ADDR_LEN;
+
+	memcpy(dev->broadcast, &ax25_bcast, AX25_ADDR_LEN);
+	dev_addr_set(dev, (u8 *)&ax25_defaddr);
+}
+
+/*
+ *	Setup a new device.
+ */
+static int bpq_new_device(struct net_device *edev)
+{
+	int err;
+	struct net_device *ndev;
+	struct bpqdev *bpq;
+
+	ndev = alloc_netdev(sizeof(struct bpqdev), "bpq%d", NET_NAME_UNKNOWN,
+			    bpq_setup);
+	if (!ndev)
+		return -ENOMEM;
+
+		
+	bpq = netdev_priv(ndev);
+	dev_hold(edev);
+	bpq->ethdev = edev;
+	bpq->axdev = ndev;
+
+	eth_broadcast_addr(bpq->dest_addr);
+	eth_broadcast_addr(bpq->acpt_addr);
+
+	err = register_netdevice(ndev);
+	if (err)
+		goto error;
+	bpq_set_lockdep_class(ndev);
+
+	/* List protected by RTNL */
+	list_add_rcu(&bpq->bpq_list, &bpq_devices);
+	return 0;
+
+ error:
+	dev_put(edev);
+	free_netdev(ndev);
+	return err;
+	
+}
+
+static void bpq_free_device(struct net_device *ndev)
+{
+	struct bpqdev *bpq = netdev_priv(ndev);
+
+	dev_put(bpq->ethdev);
+	list_del_rcu(&bpq->bpq_list);
+
+	unregister_netdevice(ndev);
+}
+
+/*
+ *	Handle device status changes.
+ */
+static int bpq_device_event(struct notifier_block *this,
+			    unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+	if (!net_eq(dev_net(dev), &init_net))
+		return NOTIFY_DONE;
+
+	if (!dev_is_ethdev(dev) && !bpq_get_ax25_dev(dev))
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case NETDEV_UP:		/* new ethernet device -> new BPQ interface */
+		if (bpq_get_ax25_dev(dev) == NULL)
+			bpq_new_device(dev);
+		break;
+
+	case NETDEV_DOWN:	/* ethernet device closed -> close BPQ interface */
+		if ((dev = bpq_get_ax25_dev(dev)) != NULL)
+			dev_close(dev);
+		break;
+
+	case NETDEV_UNREGISTER:	/* ethernet device removed -> free BPQ interface */
+		if ((dev = bpq_get_ax25_dev(dev)) != NULL)
+			bpq_free_device(dev);
+		break;
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+
+/* ------------------------------------------------------------------------ */
+
+/*
+ * Initialize driver. To be called from af_ax25 if not compiled as a
+ * module
+ */
+static int __init bpq_init_driver(void)
+{
+#ifdef CONFIG_PROC_FS
+	if (!proc_create_seq("bpqether", 0444, init_net.proc_net, &bpq_seqops)) {
+		printk(KERN_ERR
+			"bpq: cannot create /proc/net/bpqether entry.\n");
+		return -ENOENT;
+	}
+#endif  /* CONFIG_PROC_FS */
+
+	dev_add_pack(&bpq_packet_type);
+
+	register_netdevice_notifier(&bpq_dev_notifier);
+
+	printk(banner);
+
+	return 0;
+}
+
+static void __exit bpq_cleanup_driver(void)
+{
+	struct bpqdev *bpq;
+
+	dev_remove_pack(&bpq_packet_type);
+
+	unregister_netdevice_notifier(&bpq_dev_notifier);
+
+	remove_proc_entry("bpqether", init_net.proc_net);
+
+	rtnl_lock();
+	while (!list_empty(&bpq_devices)) {
+		bpq = list_entry(bpq_devices.next, struct bpqdev, bpq_list);
+		bpq_free_device(bpq->axdev);
+	}
+	rtnl_unlock();
+}
+
+MODULE_AUTHOR("Joerg Reuter DL1BKE <jreuter@yaina.de>");
+MODULE_DESCRIPTION("Transmit and receive AX.25 packets over Ethernet");
+MODULE_LICENSE("GPL");
+module_init(bpq_init_driver);
+module_exit(bpq_cleanup_driver);