| /* |
| * Copyright (C) ST-Ericsson AB 2010 |
| * Authors: Sjur Brendeland |
| * Daniel Martensson |
| * License terms: GNU General Public License (GPL) version 2 |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__ |
| |
| #include <linux/fs.h> |
| #include <linux/hardirq.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 void robust_list_del(struct list_head *delete_node) |
| { |
| struct list_head *list_node; |
| struct list_head *n; |
| ASSERT_RTNL(); |
| list_for_each_safe(list_node, n, &chnl_net_list) { |
| if (list_node == delete_node) { |
| list_del(list_node); |
| return; |
| } |
| } |
| WARN_ON(1); |
| } |
| |
| 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); |
| if (!priv) |
| return -EINVAL; |
| |
| 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; |
| |
| if (in_interrupt()) |
| netif_rx(skb); |
| else |
| netif_rx_ni(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" : "UKNOWN 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 int 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"); |
| caif_disconnect_client(dev_net(dev), &priv->chnl); |
| priv->state = CAIF_DISCONNECTED; |
| pr_debug("state disconnected\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)); |
| return 0; |
| } |
| |
| static void chnl_net_uninit(struct net_device *dev) |
| { |
| struct chnl_net *priv; |
| ASSERT_RTNL(); |
| priv = netdev_priv(dev); |
| robust_list_del(&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[]) |
| { |
| 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 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(list_node); |
| delete_device(dev); |
| } |
| rtnl_unlock(); |
| } |
| |
| module_init(chnl_init_module); |
| module_exit(chnl_exit_module); |