From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- drivers/net/wan/hdlc_x25.c | 381 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 381 insertions(+) create mode 100644 drivers/net/wan/hdlc_x25.c (limited to 'drivers/net/wan/hdlc_x25.c') diff --git a/drivers/net/wan/hdlc_x25.c b/drivers/net/wan/hdlc_x25.c new file mode 100644 index 000000000..6938cb3bd --- /dev/null +++ b/drivers/net/wan/hdlc_x25.c @@ -0,0 +1,381 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic HDLC support routines for Linux + * X.25 support + * + * Copyright (C) 1999 - 2006 Krzysztof Halasa + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct x25_state { + x25_hdlc_proto settings; + bool up; + spinlock_t up_lock; /* Protects "up" */ +}; + +static int x25_ioctl(struct net_device *dev, struct ifreq *ifr); + +static struct x25_state *state(hdlc_device *hdlc) +{ + return hdlc->state; +} + +/* These functions are callbacks called by LAPB layer */ + +static void x25_connect_disconnect(struct net_device *dev, int reason, int code) +{ + struct sk_buff *skb; + unsigned char *ptr; + + if ((skb = dev_alloc_skb(1)) == NULL) { + netdev_err(dev, "out of memory\n"); + return; + } + + ptr = skb_put(skb, 1); + *ptr = code; + + skb->protocol = x25_type_trans(skb, dev); + netif_rx(skb); +} + + + +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) +{ + unsigned char *ptr; + + if (skb_cow(skb, 1)) { + kfree_skb(skb); + return NET_RX_DROP; + } + + skb_push(skb, 1); + skb_reset_network_header(skb); + + ptr = skb->data; + *ptr = X25_IFACE_DATA; + + skb->protocol = x25_type_trans(skb, dev); + return netif_rx(skb); +} + + + +static void x25_data_transmit(struct net_device *dev, struct sk_buff *skb) +{ + hdlc_device *hdlc = dev_to_hdlc(dev); + + 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; + } + + switch (skb->data[0]) { + case X25_IFACE_DATA: /* Data to be transmitted */ + skb_pull(skb, 1); + skb_reset_network_header(skb); + if ((result = lapb_data_request(dev, skb)) != 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) { + if (result == LAPB_CONNECTED) + /* Send connect confirm. msg to level 3 */ + x25_connected(dev, 0); + else + netdev_err(dev, "LAPB connect request failed, error code = %i\n", + result); + } + break; + + case X25_IFACE_DISCONNECT: + if ((result = lapb_disconnect_request(dev)) != LAPB_OK) { + if (result == LAPB_NOTCONNECTED) + /* Send disconnect confirm. msg to level 3 */ + x25_disconnected(dev, 0); + else + netdev_err(dev, "LAPB disconnect request failed, error code = %i\n", + result); + } + break; + + default: /* to be defined */ + break; + } + + spin_unlock_bh(&x25st->up_lock); + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} + + + +static int x25_open(struct net_device *dev) +{ + static const struct lapb_register_struct cb = { + .connect_confirmation = x25_connected, + .connect_indication = x25_connected, + .disconnect_confirmation = x25_disconnected, + .disconnect_indication = x25_disconnected, + .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 -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) +{ + 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); +} + + + +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) { + dev->stats.rx_dropped++; + return NET_RX_DROP; + } + + 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, + .ioctl = x25_ioctl, + .netif_rx = x25_rx, + .xmit = x25_xmit, + .module = THIS_MODULE, +}; + + +static int x25_ioctl(struct net_device *dev, struct ifreq *ifr) +{ + x25_hdlc_proto __user *x25_s = ifr->ifr_settings.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) { + case IF_GET_PROTO: + if (dev_to_hdlc(dev)->proto != &proto) + return -EINVAL; + ifr->ifr_settings.type = IF_PROTO_X25; + if (ifr->ifr_settings.size < size) { + ifr->ifr_settings.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)) + return -EPERM; + + if (dev->flags & IFF_UP) + return -EBUSY; + + /* backward compatibility */ + if (ifr->ifr_settings.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, + sizeof(struct x25_state)))) + return result; + + memcpy(&state(hdlc)->settings, &new_settings, size); + state(hdlc)->up = false; + spin_lock_init(&state(hdlc)->up_lock); + + /* 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; + } + + return -EINVAL; +} + + +static int __init mod_init(void) +{ + register_hdlc_protocol(&proto); + return 0; +} + + + +static void __exit mod_exit(void) +{ + unregister_hdlc_protocol(&proto); +} + + +module_init(mod_init); +module_exit(mod_exit); + +MODULE_AUTHOR("Krzysztof Halasa "); +MODULE_DESCRIPTION("X.25 protocol support for generic HDLC"); +MODULE_LICENSE("GPL v2"); -- cgit v1.2.3