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Diffstat (limited to '')
| -rw-r--r-- | net/rose/rose_link.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/net/rose/rose_link.c b/net/rose/rose_link.c new file mode 100644 index 000000000..62055d306 --- /dev/null +++ b/net/rose/rose_link.c @@ -0,0 +1,289 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/rose.h> + +static void rose_ftimer_expiry(struct timer_list *); +static void rose_t0timer_expiry(struct timer_list *); + +static void rose_transmit_restart_confirmation(struct rose_neigh *neigh); +static void rose_transmit_restart_request(struct rose_neigh *neigh); + +void rose_start_ftimer(struct rose_neigh *neigh) +{ + del_timer(&neigh->ftimer); + + neigh->ftimer.function = rose_ftimer_expiry; + neigh->ftimer.expires = + jiffies + msecs_to_jiffies(sysctl_rose_link_fail_timeout); + + add_timer(&neigh->ftimer); +} + +static void rose_start_t0timer(struct rose_neigh *neigh) +{ + del_timer(&neigh->t0timer); + + neigh->t0timer.function = rose_t0timer_expiry; + neigh->t0timer.expires = + jiffies + msecs_to_jiffies(sysctl_rose_restart_request_timeout); + + add_timer(&neigh->t0timer); +} + +void rose_stop_ftimer(struct rose_neigh *neigh) +{ + del_timer(&neigh->ftimer); +} + +void rose_stop_t0timer(struct rose_neigh *neigh) +{ + del_timer(&neigh->t0timer); +} + +int rose_ftimer_running(struct rose_neigh *neigh) +{ + return timer_pending(&neigh->ftimer); +} + +static int rose_t0timer_running(struct rose_neigh *neigh) +{ + return timer_pending(&neigh->t0timer); +} + +static void rose_ftimer_expiry(struct timer_list *t) +{ +} + +static void rose_t0timer_expiry(struct timer_list *t) +{ + struct rose_neigh *neigh = from_timer(neigh, t, t0timer); + + rose_transmit_restart_request(neigh); + + neigh->dce_mode = 0; + + rose_start_t0timer(neigh); +} + +/* + * Interface to ax25_send_frame. Changes my level 2 callsign depending + * on whether we have a global ROSE callsign or use the default port + * callsign. + */ +static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh) +{ + ax25_address *rose_call; + ax25_cb *ax25s; + + if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) + rose_call = (ax25_address *)neigh->dev->dev_addr; + else + rose_call = &rose_callsign; + + ax25s = neigh->ax25; + neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); + if (ax25s) + ax25_cb_put(ax25s); + + return neigh->ax25 != NULL; +} + +/* + * Interface to ax25_link_up. Changes my level 2 callsign depending + * on whether we have a global ROSE callsign or use the default port + * callsign. + */ +static int rose_link_up(struct rose_neigh *neigh) +{ + ax25_address *rose_call; + ax25_cb *ax25s; + + if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) + rose_call = (ax25_address *)neigh->dev->dev_addr; + else + rose_call = &rose_callsign; + + ax25s = neigh->ax25; + neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); + if (ax25s) + ax25_cb_put(ax25s); + + return neigh->ax25 != NULL; +} + +/* + * This handles all restart and diagnostic frames. + */ +void rose_link_rx_restart(struct sk_buff *skb, struct rose_neigh *neigh, unsigned short frametype) +{ + struct sk_buff *skbn; + + switch (frametype) { + case ROSE_RESTART_REQUEST: + rose_stop_t0timer(neigh); + neigh->restarted = 1; + neigh->dce_mode = (skb->data[3] == ROSE_DTE_ORIGINATED); + rose_transmit_restart_confirmation(neigh); + break; + + case ROSE_RESTART_CONFIRMATION: + rose_stop_t0timer(neigh); + neigh->restarted = 1; + break; + + case ROSE_DIAGNOSTIC: + pr_warn("ROSE: received diagnostic #%d - %3ph\n", skb->data[3], + skb->data + 4); + break; + + default: + printk(KERN_WARNING "ROSE: received unknown %02X with LCI 000\n", frametype); + break; + } + + if (neigh->restarted) { + while ((skbn = skb_dequeue(&neigh->queue)) != NULL) + if (!rose_send_frame(skbn, neigh)) + kfree_skb(skbn); + } +} + +/* + * This routine is called when a Restart Request is needed + */ +static void rose_transmit_restart_request(struct rose_neigh *neigh) +{ + struct sk_buff *skb; + unsigned char *dptr; + int len; + + len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3; + + if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) + return; + + skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); + + dptr = skb_put(skb, ROSE_MIN_LEN + 3); + + *dptr++ = AX25_P_ROSE; + *dptr++ = ROSE_GFI; + *dptr++ = 0x00; + *dptr++ = ROSE_RESTART_REQUEST; + *dptr++ = ROSE_DTE_ORIGINATED; + *dptr++ = 0; + + if (!rose_send_frame(skb, neigh)) + kfree_skb(skb); +} + +/* + * This routine is called when a Restart Confirmation is needed + */ +static void rose_transmit_restart_confirmation(struct rose_neigh *neigh) +{ + struct sk_buff *skb; + unsigned char *dptr; + int len; + + len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 1; + + if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) + return; + + skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); + + dptr = skb_put(skb, ROSE_MIN_LEN + 1); + + *dptr++ = AX25_P_ROSE; + *dptr++ = ROSE_GFI; + *dptr++ = 0x00; + *dptr++ = ROSE_RESTART_CONFIRMATION; + + if (!rose_send_frame(skb, neigh)) + kfree_skb(skb); +} + +/* + * This routine is called when a Clear Request is needed outside of the context + * of a connected socket. + */ +void rose_transmit_clear_request(struct rose_neigh *neigh, unsigned int lci, unsigned char cause, unsigned char diagnostic) +{ + struct sk_buff *skb; + unsigned char *dptr; + int len; + + len = AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN + ROSE_MIN_LEN + 3; + + if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) + return; + + skb_reserve(skb, AX25_BPQ_HEADER_LEN + AX25_MAX_HEADER_LEN); + + dptr = skb_put(skb, ROSE_MIN_LEN + 3); + + *dptr++ = AX25_P_ROSE; + *dptr++ = ((lci >> 8) & 0x0F) | ROSE_GFI; + *dptr++ = ((lci >> 0) & 0xFF); + *dptr++ = ROSE_CLEAR_REQUEST; + *dptr++ = cause; + *dptr++ = diagnostic; + + if (!rose_send_frame(skb, neigh)) + kfree_skb(skb); +} + +void rose_transmit_link(struct sk_buff *skb, struct rose_neigh *neigh) +{ + unsigned char *dptr; + + if (neigh->loopback) { + rose_loopback_queue(skb, neigh); + return; + } + + if (!rose_link_up(neigh)) + neigh->restarted = 0; + + dptr = skb_push(skb, 1); + *dptr++ = AX25_P_ROSE; + + if (neigh->restarted) { + if (!rose_send_frame(skb, neigh)) + kfree_skb(skb); + } else { + skb_queue_tail(&neigh->queue, skb); + + if (!rose_t0timer_running(neigh)) { + rose_transmit_restart_request(neigh); + neigh->dce_mode = 0; + rose_start_t0timer(neigh); + } + } +} |