1 files changed, 531 insertions, 0 deletions

diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
new file mode 100644
index 000000000..f35fc87c4
--- /dev/null
+++ b/net/caif/chnl_net.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Authors:	Sjur Brendeland
+ *		Daniel Martensson
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/if_ether.h>
+#include <linux/ip.h>
+#include <linux/sched.h>
+#include <linux/sockios.h>
+#include <linux/caif/if_caif.h>
+#include <net/rtnetlink.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/caif_dev.h>
+
+/* GPRS PDP connection has MTU to 1500 */
+#define GPRS_PDP_MTU 1500
+/* 5 sec. connect timeout */
+#define CONNECT_TIMEOUT (5 * HZ)
+#define CAIF_NET_DEFAULT_QUEUE_LEN 500
+#define UNDEF_CONNID 0xffffffff
+
+/*This list is protected by the rtnl lock. */
+static LIST_HEAD(chnl_net_list);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK("caif");
+
+enum caif_states {
+	CAIF_CONNECTED		= 1,
+	CAIF_CONNECTING,
+	CAIF_DISCONNECTED,
+	CAIF_SHUTDOWN
+};
+
+struct chnl_net {
+	struct cflayer chnl;
+	struct caif_connect_request conn_req;
+	struct list_head list_field;
+	struct net_device *netdev;
+	char name[256];
+	wait_queue_head_t netmgmt_wq;
+	/* Flow status to remember and control the transmission. */
+	bool flowenabled;
+	enum caif_states state;
+};
+
+static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt)
+{
+	struct sk_buff *skb;
+	struct chnl_net *priv;
+	int pktlen;
+	const u8 *ip_version;
+	u8 buf;
+
+	priv = container_of(layr, struct chnl_net, chnl);
+
+	skb = (struct sk_buff *) cfpkt_tonative(pkt);
+
+	/* Get length of CAIF packet. */
+	pktlen = skb->len;
+
+	/* Pass some minimum information and
+	 * send the packet to the net stack.
+	 */
+	skb->dev = priv->netdev;
+
+	/* check the version of IP */
+	ip_version = skb_header_pointer(skb, 0, 1, &buf);
+	if (!ip_version) {
+		kfree_skb(skb);
+		return -EINVAL;
+	}
+
+	switch (*ip_version >> 4) {
+	case 4:
+		skb->protocol = htons(ETH_P_IP);
+		break;
+	case 6:
+		skb->protocol = htons(ETH_P_IPV6);
+		break;
+	default:
+		kfree_skb(skb);
+		priv->netdev->stats.rx_errors++;
+		return -EINVAL;
+	}
+
+	/* If we change the header in loop mode, the checksum is corrupted. */
+	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+	else
+		skb->ip_summed = CHECKSUM_NONE;
+
+	netif_rx(skb);
+
+	/* Update statistics. */
+	priv->netdev->stats.rx_packets++;
+	priv->netdev->stats.rx_bytes += pktlen;
+
+	return 0;
+}
+
+static int delete_device(struct chnl_net *dev)
+{
+	ASSERT_RTNL();
+	if (dev->netdev)
+		unregister_netdevice(dev->netdev);
+	return 0;
+}
+
+static void close_work(struct work_struct *work)
+{
+	struct chnl_net *dev = NULL;
+	struct list_head *list_node;
+	struct list_head *_tmp;
+
+	rtnl_lock();
+	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
+		dev = list_entry(list_node, struct chnl_net, list_field);
+		if (dev->state == CAIF_SHUTDOWN)
+			dev_close(dev->netdev);
+	}
+	rtnl_unlock();
+}
+static DECLARE_WORK(close_worker, close_work);
+
+static void chnl_hold(struct cflayer *lyr)
+{
+	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
+	dev_hold(priv->netdev);
+}
+
+static void chnl_put(struct cflayer *lyr)
+{
+	struct chnl_net *priv = container_of(lyr, struct chnl_net, chnl);
+	dev_put(priv->netdev);
+}
+
+static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
+			     int phyid)
+{
+	struct chnl_net *priv = container_of(layr, struct chnl_net, chnl);
+	pr_debug("NET flowctrl func called flow: %s\n",
+		flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
+		flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" :
+		flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
+		flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" :
+		flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" :
+		flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ?
+		 "REMOTE_SHUTDOWN" : "UNKNOWN CTRL COMMAND");
+
+
+
+	switch (flow) {
+	case CAIF_CTRLCMD_FLOW_OFF_IND:
+		priv->flowenabled = false;
+		netif_stop_queue(priv->netdev);
+		break;
+	case CAIF_CTRLCMD_DEINIT_RSP:
+		priv->state = CAIF_DISCONNECTED;
+		break;
+	case CAIF_CTRLCMD_INIT_FAIL_RSP:
+		priv->state = CAIF_DISCONNECTED;
+		wake_up_interruptible(&priv->netmgmt_wq);
+		break;
+	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
+		priv->state = CAIF_SHUTDOWN;
+		netif_tx_disable(priv->netdev);
+		schedule_work(&close_worker);
+		break;
+	case CAIF_CTRLCMD_FLOW_ON_IND:
+		priv->flowenabled = true;
+		netif_wake_queue(priv->netdev);
+		break;
+	case CAIF_CTRLCMD_INIT_RSP:
+		caif_client_register_refcnt(&priv->chnl, chnl_hold, chnl_put);
+		priv->state = CAIF_CONNECTED;
+		priv->flowenabled = true;
+		netif_wake_queue(priv->netdev);
+		wake_up_interruptible(&priv->netmgmt_wq);
+		break;
+	default:
+		break;
+	}
+}
+
+static netdev_tx_t chnl_net_start_xmit(struct sk_buff *skb,
+				       struct net_device *dev)
+{
+	struct chnl_net *priv;
+	struct cfpkt *pkt = NULL;
+	int len;
+	int result = -1;
+	/* Get our private data. */
+	priv = netdev_priv(dev);
+
+	if (skb->len > priv->netdev->mtu) {
+		pr_warn("Size of skb exceeded MTU\n");
+		kfree_skb(skb);
+		dev->stats.tx_errors++;
+		return NETDEV_TX_OK;
+	}
+
+	if (!priv->flowenabled) {
+		pr_debug("dropping packets flow off\n");
+		kfree_skb(skb);
+		dev->stats.tx_dropped++;
+		return NETDEV_TX_OK;
+	}
+
+	if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP)
+		swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr);
+
+	/* Store original SKB length. */
+	len = skb->len;
+
+	pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb);
+
+	/* Send the packet down the stack. */
+	result = priv->chnl.dn->transmit(priv->chnl.dn, pkt);
+	if (result) {
+		dev->stats.tx_dropped++;
+		return NETDEV_TX_OK;
+	}
+
+	/* Update statistics. */
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += len;
+
+	return NETDEV_TX_OK;
+}
+
+static int chnl_net_open(struct net_device *dev)
+{
+	struct chnl_net *priv = NULL;
+	int result = -1;
+	int llifindex, headroom, tailroom, mtu;
+	struct net_device *lldev;
+	ASSERT_RTNL();
+	priv = netdev_priv(dev);
+	if (!priv) {
+		pr_debug("chnl_net_open: no priv\n");
+		return -ENODEV;
+	}
+
+	if (priv->state != CAIF_CONNECTING) {
+		priv->state = CAIF_CONNECTING;
+		result = caif_connect_client(dev_net(dev), &priv->conn_req,
+						&priv->chnl, &llifindex,
+						&headroom, &tailroom);
+		if (result != 0) {
+				pr_debug("err: "
+					 "Unable to register and open device,"
+					 " Err:%d\n",
+					 result);
+				goto error;
+		}
+
+		lldev = __dev_get_by_index(dev_net(dev), llifindex);
+
+		if (lldev == NULL) {
+			pr_debug("no interface?\n");
+			result = -ENODEV;
+			goto error;
+		}
+
+		dev->needed_tailroom = tailroom + lldev->needed_tailroom;
+		dev->hard_header_len = headroom + lldev->hard_header_len +
+			lldev->needed_tailroom;
+
+		/*
+		 * MTU, head-room etc is not know before we have a
+		 * CAIF link layer device available. MTU calculation may
+		 * override initial RTNL configuration.
+		 * MTU is minimum of current mtu, link layer mtu pluss
+		 * CAIF head and tail, and PDP GPRS contexts max MTU.
+		 */
+		mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
+		mtu = min_t(int, GPRS_PDP_MTU, mtu);
+		dev_set_mtu(dev, mtu);
+
+		if (mtu < 100) {
+			pr_warn("CAIF Interface MTU too small (%d)\n", mtu);
+			result = -ENODEV;
+			goto error;
+		}
+	}
+
+	rtnl_unlock();  /* Release RTNL lock during connect wait */
+
+	result = wait_event_interruptible_timeout(priv->netmgmt_wq,
+						priv->state != CAIF_CONNECTING,
+						CONNECT_TIMEOUT);
+
+	rtnl_lock();
+
+	if (result == -ERESTARTSYS) {
+		pr_debug("wait_event_interruptible woken by a signal\n");
+		result = -ERESTARTSYS;
+		goto error;
+	}
+
+	if (result == 0) {
+		pr_debug("connect timeout\n");
+		result = -ETIMEDOUT;
+		goto error;
+	}
+
+	if (priv->state != CAIF_CONNECTED) {
+		pr_debug("connect failed\n");
+		result = -ECONNREFUSED;
+		goto error;
+	}
+	pr_debug("CAIF Netdevice connected\n");
+	return 0;
+
+error:
+	caif_disconnect_client(dev_net(dev), &priv->chnl);
+	priv->state = CAIF_DISCONNECTED;
+	pr_debug("state disconnected\n");
+	return result;
+
+}
+
+static int chnl_net_stop(struct net_device *dev)
+{
+	struct chnl_net *priv;
+
+	ASSERT_RTNL();
+	priv = netdev_priv(dev);
+	priv->state = CAIF_DISCONNECTED;
+	caif_disconnect_client(dev_net(dev), &priv->chnl);
+	return 0;
+}
+
+static int chnl_net_init(struct net_device *dev)
+{
+	struct chnl_net *priv;
+	ASSERT_RTNL();
+	priv = netdev_priv(dev);
+	strncpy(priv->name, dev->name, sizeof(priv->name));
+	INIT_LIST_HEAD(&priv->list_field);
+	return 0;
+}
+
+static void chnl_net_uninit(struct net_device *dev)
+{
+	struct chnl_net *priv;
+	ASSERT_RTNL();
+	priv = netdev_priv(dev);
+	list_del_init(&priv->list_field);
+}
+
+static const struct net_device_ops netdev_ops = {
+	.ndo_open = chnl_net_open,
+	.ndo_stop = chnl_net_stop,
+	.ndo_init = chnl_net_init,
+	.ndo_uninit = chnl_net_uninit,
+	.ndo_start_xmit = chnl_net_start_xmit,
+};
+
+static void chnl_net_destructor(struct net_device *dev)
+{
+	struct chnl_net *priv = netdev_priv(dev);
+	caif_free_client(&priv->chnl);
+}
+
+static void ipcaif_net_setup(struct net_device *dev)
+{
+	struct chnl_net *priv;
+	dev->netdev_ops = &netdev_ops;
+	dev->needs_free_netdev = true;
+	dev->priv_destructor = chnl_net_destructor;
+	dev->flags |= IFF_NOARP;
+	dev->flags |= IFF_POINTOPOINT;
+	dev->mtu = GPRS_PDP_MTU;
+	dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN;
+
+	priv = netdev_priv(dev);
+	priv->chnl.receive = chnl_recv_cb;
+	priv->chnl.ctrlcmd = chnl_flowctrl_cb;
+	priv->netdev = dev;
+	priv->conn_req.protocol = CAIFPROTO_DATAGRAM;
+	priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
+	priv->conn_req.priority = CAIF_PRIO_LOW;
+	/* Insert illegal value */
+	priv->conn_req.sockaddr.u.dgm.connection_id = UNDEF_CONNID;
+	priv->flowenabled = false;
+
+	init_waitqueue_head(&priv->netmgmt_wq);
+}
+
+
+static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct chnl_net *priv;
+	u8 loop;
+	priv = netdev_priv(dev);
+	if (nla_put_u32(skb, IFLA_CAIF_IPV4_CONNID,
+			priv->conn_req.sockaddr.u.dgm.connection_id) ||
+	    nla_put_u32(skb, IFLA_CAIF_IPV6_CONNID,
+			priv->conn_req.sockaddr.u.dgm.connection_id))
+		goto nla_put_failure;
+	loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP;
+	if (nla_put_u8(skb, IFLA_CAIF_LOOPBACK, loop))
+		goto nla_put_failure;
+	return 0;
+nla_put_failure:
+	return -EMSGSIZE;
+
+}
+
+static void caif_netlink_parms(struct nlattr *data[],
+			       struct caif_connect_request *conn_req)
+{
+	if (!data) {
+		pr_warn("no params data found\n");
+		return;
+	}
+	if (data[IFLA_CAIF_IPV4_CONNID])
+		conn_req->sockaddr.u.dgm.connection_id =
+			nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]);
+	if (data[IFLA_CAIF_IPV6_CONNID])
+		conn_req->sockaddr.u.dgm.connection_id =
+			nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]);
+	if (data[IFLA_CAIF_LOOPBACK]) {
+		if (nla_get_u8(data[IFLA_CAIF_LOOPBACK]))
+			conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP;
+		else
+			conn_req->protocol = CAIFPROTO_DATAGRAM;
+	}
+}
+
+static int ipcaif_newlink(struct net *src_net, struct net_device *dev,
+			  struct nlattr *tb[], struct nlattr *data[],
+			  struct netlink_ext_ack *extack)
+{
+	int ret;
+	struct chnl_net *caifdev;
+	ASSERT_RTNL();
+	caifdev = netdev_priv(dev);
+	caif_netlink_parms(data, &caifdev->conn_req);
+
+	ret = register_netdevice(dev);
+	if (ret)
+		pr_warn("device rtml registration failed\n");
+	else
+		list_add(&caifdev->list_field, &chnl_net_list);
+
+	/* Use ifindex as connection id, and use loopback channel default. */
+	if (caifdev->conn_req.sockaddr.u.dgm.connection_id == UNDEF_CONNID) {
+		caifdev->conn_req.sockaddr.u.dgm.connection_id = dev->ifindex;
+		caifdev->conn_req.protocol = CAIFPROTO_DATAGRAM_LOOP;
+	}
+	return ret;
+}
+
+static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[],
+			     struct nlattr *data[],
+			     struct netlink_ext_ack *extack)
+{
+	struct chnl_net *caifdev;
+	ASSERT_RTNL();
+	caifdev = netdev_priv(dev);
+	caif_netlink_parms(data, &caifdev->conn_req);
+	netdev_state_change(dev);
+	return 0;
+}
+
+static size_t ipcaif_get_size(const struct net_device *dev)
+{
+	return
+		/* IFLA_CAIF_IPV4_CONNID */
+		nla_total_size(4) +
+		/* IFLA_CAIF_IPV6_CONNID */
+		nla_total_size(4) +
+		/* IFLA_CAIF_LOOPBACK */
+		nla_total_size(2) +
+		0;
+}
+
+static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = {
+	[IFLA_CAIF_IPV4_CONNID]	      = { .type = NLA_U32 },
+	[IFLA_CAIF_IPV6_CONNID]	      = { .type = NLA_U32 },
+	[IFLA_CAIF_LOOPBACK]	      = { .type = NLA_U8 }
+};
+
+
+static struct rtnl_link_ops ipcaif_link_ops __read_mostly = {
+	.kind		= "caif",
+	.priv_size	= sizeof(struct chnl_net),
+	.setup		= ipcaif_net_setup,
+	.maxtype	= IFLA_CAIF_MAX,
+	.policy		= ipcaif_policy,
+	.newlink	= ipcaif_newlink,
+	.changelink	= ipcaif_changelink,
+	.get_size	= ipcaif_get_size,
+	.fill_info	= ipcaif_fill_info,
+
+};
+
+static int __init chnl_init_module(void)
+{
+	return rtnl_link_register(&ipcaif_link_ops);
+}
+
+static void __exit chnl_exit_module(void)
+{
+	struct chnl_net *dev = NULL;
+	struct list_head *list_node;
+	struct list_head *_tmp;
+	rtnl_link_unregister(&ipcaif_link_ops);
+	rtnl_lock();
+	list_for_each_safe(list_node, _tmp, &chnl_net_list) {
+		dev = list_entry(list_node, struct chnl_net, list_field);
+		list_del_init(list_node);
+		delete_device(dev);
+	}
+	rtnl_unlock();
+}
+
+module_init(chnl_init_module);
+module_exit(chnl_exit_module);