diff options
Diffstat (limited to 'drivers/net/wan/hdlc_x25.c')
| -rw-r--r-- | drivers/net/wan/hdlc_x25.c | 247 |
1 files changed, 194 insertions, 53 deletions
diff --git a/drivers/net/wan/hdlc_x25.c b/drivers/net/wan/hdlc_x25.c index a49aec5efd20..f72c92c24003 100644 --- a/drivers/net/wan/hdlc_x25.c +++ b/drivers/net/wan/hdlc_x25.c @@ -1,12 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * Generic HDLC support routines for Linux * X.25 support * * Copyright (C) 1999 - 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> @@ -24,84 +21,131 @@ #include <linux/skbuff.h> #include <net/x25device.h> -static int x25_ioctl(struct net_device *dev, struct ifreq *ifr); +struct x25_state { + x25_hdlc_proto settings; + bool up; + spinlock_t up_lock; /* Protects "up" */ + struct sk_buff_head rx_queue; + struct tasklet_struct rx_tasklet; +}; + +static int x25_ioctl(struct net_device *dev, struct if_settings *ifs); + +static struct x25_state *state(hdlc_device *hdlc) +{ + return hdlc->state; +} + +static void x25_rx_queue_kick(struct tasklet_struct *t) +{ + struct x25_state *x25st = from_tasklet(x25st, t, rx_tasklet); + struct sk_buff *skb = skb_dequeue(&x25st->rx_queue); + + while (skb) { + netif_receive_skb_core(skb); + skb = skb_dequeue(&x25st->rx_queue); + } +} /* These functions are callbacks called by LAPB layer */ static void x25_connect_disconnect(struct net_device *dev, int reason, int code) { + struct x25_state *x25st = state(dev_to_hdlc(dev)); struct sk_buff *skb; unsigned char *ptr; - if ((skb = dev_alloc_skb(1)) == NULL) { - netdev_err(dev, "out of memory\n"); + skb = __dev_alloc_skb(1, GFP_ATOMIC | __GFP_NOMEMALLOC); + if (!skb) return; - } ptr = skb_put(skb, 1); *ptr = code; skb->protocol = x25_type_trans(skb, dev); - netif_rx(skb); -} - + skb_queue_tail(&x25st->rx_queue, skb); + tasklet_schedule(&x25st->rx_tasklet); +} static void x25_connected(struct net_device *dev, int reason) { x25_connect_disconnect(dev, reason, X25_IFACE_CONNECT); } - - static void x25_disconnected(struct net_device *dev, int reason) { x25_connect_disconnect(dev, reason, X25_IFACE_DISCONNECT); } - - static int x25_data_indication(struct net_device *dev, struct sk_buff *skb) { + struct x25_state *x25st = state(dev_to_hdlc(dev)); unsigned char *ptr; - skb_push(skb, 1); - - if (skb_cow(skb, 1)) + if (skb_cow(skb, 1)) { + kfree_skb(skb); return NET_RX_DROP; + } + + skb_push(skb, 1); ptr = skb->data; *ptr = X25_IFACE_DATA; skb->protocol = x25_type_trans(skb, dev); - return netif_rx(skb); -} - + skb_queue_tail(&x25st->rx_queue, skb); + tasklet_schedule(&x25st->rx_tasklet); + return NET_RX_SUCCESS; +} static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb) { hdlc_device *hdlc = dev_to_hdlc(dev); - hdlc->xmit(skb, dev); /* Ignore return value :-( */ -} + skb_reset_network_header(skb); + skb->protocol = hdlc_type_trans(skb, dev); + + if (dev_nit_active(dev)) + dev_queue_xmit_nit(skb, dev); + hdlc->xmit(skb, dev); /* Ignore return value :-( */ +} static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) { + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); int result; + /* There should be a pseudo header of 1 byte added by upper layers. + * Check to make sure it is there before reading it. + */ + if (skb->len < 1) { + kfree_skb(skb); + return NETDEV_TX_OK; + } + + spin_lock_bh(&x25st->up_lock); + if (!x25st->up) { + spin_unlock_bh(&x25st->up_lock); + kfree_skb(skb); + return NETDEV_TX_OK; + } - /* X.25 to LAPB */ switch (skb->data[0]) { case X25_IFACE_DATA: /* Data to be transmitted */ skb_pull(skb, 1); - if ((result = lapb_data_request(dev, skb)) != LAPB_OK) + result = lapb_data_request(dev, skb); + if (result != LAPB_OK) dev_kfree_skb(skb); + spin_unlock_bh(&x25st->up_lock); return NETDEV_TX_OK; case X25_IFACE_CONNECT: - if ((result = lapb_connect_request(dev))!= LAPB_OK) { + result = lapb_connect_request(dev); + if (result != LAPB_OK) { if (result == LAPB_CONNECTED) /* Send connect confirm. msg to level 3 */ x25_connected(dev, 0); @@ -112,7 +156,8 @@ static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) break; case X25_IFACE_DISCONNECT: - if ((result = lapb_disconnect_request(dev)) != LAPB_OK) { + result = lapb_disconnect_request(dev); + if (result != LAPB_OK) { if (result == LAPB_NOTCONNECTED) /* Send disconnect confirm. msg to level 3 */ x25_disconnected(dev, 0); @@ -126,15 +171,13 @@ static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev) break; } + spin_unlock_bh(&x25st->up_lock); dev_kfree_skb(skb); return NETDEV_TX_OK; } - - static int x25_open(struct net_device *dev) { - int result; static const struct lapb_register_struct cb = { .connect_confirmation = x25_connected, .connect_indication = x25_connected, @@ -143,40 +186,85 @@ static int x25_open(struct net_device *dev) .data_indication = x25_data_indication, .data_transmit = x25_data_transmit, }; + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); + struct lapb_parms_struct params; + int result; result = lapb_register(dev, &cb); if (result != LAPB_OK) - return result; - return 0; -} + return -ENOMEM; + + result = lapb_getparms(dev, ¶ms); + if (result != LAPB_OK) + return -EINVAL; + + if (state(hdlc)->settings.dce) + params.mode = params.mode | LAPB_DCE; + + if (state(hdlc)->settings.modulo == 128) + params.mode = params.mode | LAPB_EXTENDED; + + params.window = state(hdlc)->settings.window; + params.t1 = state(hdlc)->settings.t1; + params.t2 = state(hdlc)->settings.t2; + params.n2 = state(hdlc)->settings.n2; + result = lapb_setparms(dev, ¶ms); + if (result != LAPB_OK) + return -EINVAL; + spin_lock_bh(&x25st->up_lock); + x25st->up = true; + spin_unlock_bh(&x25st->up_lock); + + return 0; +} static void x25_close(struct net_device *dev) { - lapb_unregister(dev); -} + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); + spin_lock_bh(&x25st->up_lock); + x25st->up = false; + spin_unlock_bh(&x25st->up_lock); + lapb_unregister(dev); + tasklet_kill(&x25st->rx_tasklet); +} static int x25_rx(struct sk_buff *skb) { struct net_device *dev = skb->dev; + hdlc_device *hdlc = dev_to_hdlc(dev); + struct x25_state *x25st = state(hdlc); - if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) { + skb = skb_share_check(skb, GFP_ATOMIC); + if (!skb) { dev->stats.rx_dropped++; return NET_RX_DROP; } - if (lapb_data_received(dev, skb) == LAPB_OK) + spin_lock_bh(&x25st->up_lock); + if (!x25st->up) { + spin_unlock_bh(&x25st->up_lock); + kfree_skb(skb); + dev->stats.rx_dropped++; + return NET_RX_DROP; + } + + if (lapb_data_received(dev, skb) == LAPB_OK) { + spin_unlock_bh(&x25st->up_lock); return NET_RX_SUCCESS; + } + spin_unlock_bh(&x25st->up_lock); dev->stats.rx_errors++; dev_kfree_skb_any(skb); return NET_RX_DROP; } - static struct hdlc_proto proto = { .open = x25_open, .close = x25_close, @@ -186,18 +274,26 @@ static struct hdlc_proto proto = { .module = THIS_MODULE, }; - -static int x25_ioctl(struct net_device *dev, struct ifreq *ifr) +static int x25_ioctl(struct net_device *dev, struct if_settings *ifs) { + x25_hdlc_proto __user *x25_s = ifs->ifs_ifsu.x25; + const size_t size = sizeof(x25_hdlc_proto); hdlc_device *hdlc = dev_to_hdlc(dev); + x25_hdlc_proto new_settings; int result; - switch (ifr->ifr_settings.type) { + switch (ifs->type) { case IF_GET_PROTO: if (dev_to_hdlc(dev)->proto != &proto) return -EINVAL; - ifr->ifr_settings.type = IF_PROTO_X25; - return 0; /* return protocol only, no settable parameters */ + ifs->type = IF_PROTO_X25; + if (ifs->size < size) { + ifs->size = size; /* data size wanted */ + return -ENOBUFS; + } + if (copy_to_user(x25_s, &state(hdlc)->settings, size)) + return -EFAULT; + return 0; case IF_PROTO_X25: if (!capable(CAP_NET_ADMIN)) @@ -206,13 +302,62 @@ static int x25_ioctl(struct net_device *dev, struct ifreq *ifr) if (dev->flags & IFF_UP) return -EBUSY; - result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT); + /* backward compatibility */ + if (ifs->size == 0) { + new_settings.dce = 0; + new_settings.modulo = 8; + new_settings.window = 7; + new_settings.t1 = 3; + new_settings.t2 = 1; + new_settings.n2 = 10; + } else { + if (copy_from_user(&new_settings, x25_s, size)) + return -EFAULT; + + if ((new_settings.dce != 0 && + new_settings.dce != 1) || + (new_settings.modulo != 8 && + new_settings.modulo != 128) || + new_settings.window < 1 || + (new_settings.modulo == 8 && + new_settings.window > 7) || + (new_settings.modulo == 128 && + new_settings.window > 127) || + new_settings.t1 < 1 || + new_settings.t1 > 255 || + new_settings.t2 < 1 || + new_settings.t2 > 255 || + new_settings.n2 < 1 || + new_settings.n2 > 255) + return -EINVAL; + } + + result = hdlc->attach(dev, ENCODING_NRZ, + PARITY_CRC16_PR1_CCITT); if (result) return result; - if ((result = attach_hdlc_protocol(dev, &proto, 0))) + result = attach_hdlc_protocol(dev, &proto, + sizeof(struct x25_state)); + if (result) return result; + + memcpy(&state(hdlc)->settings, &new_settings, size); + state(hdlc)->up = false; + spin_lock_init(&state(hdlc)->up_lock); + skb_queue_head_init(&state(hdlc)->rx_queue); + tasklet_setup(&state(hdlc)->rx_tasklet, x25_rx_queue_kick); + + /* There's no header_ops so hard_header_len should be 0. */ + dev->hard_header_len = 0; + /* When transmitting data: + * first we'll remove a pseudo header of 1 byte, + * then we'll prepend an LAPB header of at most 3 bytes. + */ + dev->needed_headroom = 3 - 1; + dev->type = ARPHRD_X25; + call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev); netif_dormant_off(dev); return 0; } @@ -220,23 +365,19 @@ static int x25_ioctl(struct net_device *dev, struct ifreq *ifr) return -EINVAL; } - -static int __init mod_init(void) +static int __init hdlc_x25_init(void) { register_hdlc_protocol(&proto); return 0; } - - -static void __exit mod_exit(void) +static void __exit hdlc_x25_exit(void) { unregister_hdlc_protocol(&proto); } - -module_init(mod_init); -module_exit(mod_exit); +module_init(hdlc_x25_init); +module_exit(hdlc_x25_exit); MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>"); MODULE_DESCRIPTION("X.25 protocol support for generic HDLC"); |