diff options
Diffstat (limited to 'net/ax25/ax25_route.c')
-rw-r--r-- | net/ax25/ax25_route.c | 534 |
1 files changed, 534 insertions, 0 deletions
diff --git a/net/ax25/ax25_route.c b/net/ax25/ax25_route.c new file mode 100644 index 0000000..44b99b1f --- /dev/null +++ b/net/ax25/ax25_route.c @@ -0,0 +1,534 @@ +/* + * 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) Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk) + * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + * Copyright (C) Steven Whitehouse GW7RRM (stevew@acm.org) + * Copyright (C) Joerg Reuter DL1BKE (jreuter@yaina.de) + * Copyright (C) Hans-Joachim Hetscher DD8NE (dd8ne@bnv-bamberg.de) + * Copyright (C) Frederic Rible F1OAT (frible@teaser.fr) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/timer.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/spinlock.h> +#include <net/sock.h> +#include <asm/uaccess.h> +#include <asm/system.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/seq_file.h> + +static ax25_route *ax25_route_list; +static DEFINE_RWLOCK(ax25_route_lock); + +static ax25_route *ax25_get_route(ax25_address *, struct net_device *); + +void ax25_rt_device_down(struct net_device *dev) +{ + ax25_route *s, *t, *ax25_rt; + + write_lock(&ax25_route_lock); + ax25_rt = ax25_route_list; + while (ax25_rt != NULL) { + s = ax25_rt; + ax25_rt = ax25_rt->next; + + if (s->dev == dev) { + if (ax25_route_list == s) { + ax25_route_list = s->next; + if (s->digipeat != NULL) + kfree(s->digipeat); + kfree(s); + } else { + for (t = ax25_route_list; t != NULL; t = t->next) { + if (t->next == s) { + t->next = s->next; + if (s->digipeat != NULL) + kfree(s->digipeat); + kfree(s); + break; + } + } + } + } + } + write_unlock(&ax25_route_lock); +} + +static int ax25_rt_add(struct ax25_routes_struct *route) +{ + ax25_route *ax25_rt; + ax25_dev *ax25_dev; + int i; + + if ((ax25_dev = ax25_addr_ax25dev(&route->port_addr)) == NULL) + return -EINVAL; + if (route->digi_count > AX25_MAX_DIGIS) + return -EINVAL; + + write_lock(&ax25_route_lock); + + ax25_rt = ax25_route_list; + while (ax25_rt != NULL) { + if (ax25cmp(&ax25_rt->callsign, &route->dest_addr) == 0 && + ax25_rt->dev == ax25_dev->dev) { + if (ax25_rt->digipeat != NULL) { + kfree(ax25_rt->digipeat); + ax25_rt->digipeat = NULL; + } + if (route->digi_count != 0) { + if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { + write_unlock(&ax25_route_lock); + return -ENOMEM; + } + ax25_rt->digipeat->lastrepeat = -1; + ax25_rt->digipeat->ndigi = route->digi_count; + for (i = 0; i < route->digi_count; i++) { + ax25_rt->digipeat->repeated[i] = 0; + ax25_rt->digipeat->calls[i] = route->digi_addr[i]; + } + } + write_unlock(&ax25_route_lock); + return 0; + } + ax25_rt = ax25_rt->next; + } + + if ((ax25_rt = kmalloc(sizeof(ax25_route), GFP_ATOMIC)) == NULL) { + write_unlock(&ax25_route_lock); + return -ENOMEM; + } + + atomic_set(&ax25_rt->ref, 0); + ax25_rt->callsign = route->dest_addr; + ax25_rt->dev = ax25_dev->dev; + ax25_rt->digipeat = NULL; + ax25_rt->ip_mode = ' '; + if (route->digi_count != 0) { + if ((ax25_rt->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { + write_unlock(&ax25_route_lock); + kfree(ax25_rt); + return -ENOMEM; + } + ax25_rt->digipeat->lastrepeat = -1; + ax25_rt->digipeat->ndigi = route->digi_count; + for (i = 0; i < route->digi_count; i++) { + ax25_rt->digipeat->repeated[i] = 0; + ax25_rt->digipeat->calls[i] = route->digi_addr[i]; + } + } + ax25_rt->next = ax25_route_list; + ax25_route_list = ax25_rt; + write_unlock(&ax25_route_lock); + + return 0; +} + +static void ax25_rt_destroy(ax25_route *ax25_rt) +{ + if (atomic_read(&ax25_rt->ref) == 0) { + if (ax25_rt->digipeat != NULL) + kfree(ax25_rt->digipeat); + kfree(ax25_rt); + return; + } + + /* + * Uh... Route is still in use; we can't yet destroy it. Retry later. + */ + init_timer(&ax25_rt->timer); + ax25_rt->timer.data = (unsigned long) ax25_rt; + ax25_rt->timer.function = (void *) ax25_rt_destroy; + ax25_rt->timer.expires = jiffies + 5 * HZ; + + add_timer(&ax25_rt->timer); +} + +static int ax25_rt_del(struct ax25_routes_struct *route) +{ + ax25_route *s, *t, *ax25_rt; + ax25_dev *ax25_dev; + + if ((ax25_dev = ax25_addr_ax25dev(&route->port_addr)) == NULL) + return -EINVAL; + + write_lock(&ax25_route_lock); + + ax25_rt = ax25_route_list; + while (ax25_rt != NULL) { + s = ax25_rt; + ax25_rt = ax25_rt->next; + if (s->dev == ax25_dev->dev && + ax25cmp(&route->dest_addr, &s->callsign) == 0) { + if (ax25_route_list == s) { + ax25_route_list = s->next; + ax25_rt_destroy(s); + } else { + for (t = ax25_route_list; t != NULL; t = t->next) { + if (t->next == s) { + t->next = s->next; + ax25_rt_destroy(s); + break; + } + } + } + } + } + write_unlock(&ax25_route_lock); + + return 0; +} + +static int ax25_rt_opt(struct ax25_route_opt_struct *rt_option) +{ + ax25_route *ax25_rt; + ax25_dev *ax25_dev; + int err = 0; + + if ((ax25_dev = ax25_addr_ax25dev(&rt_option->port_addr)) == NULL) + return -EINVAL; + + write_lock(&ax25_route_lock); + + ax25_rt = ax25_route_list; + while (ax25_rt != NULL) { + if (ax25_rt->dev == ax25_dev->dev && + ax25cmp(&rt_option->dest_addr, &ax25_rt->callsign) == 0) { + switch (rt_option->cmd) { + case AX25_SET_RT_IPMODE: + switch (rt_option->arg) { + case ' ': + case 'D': + case 'V': + ax25_rt->ip_mode = rt_option->arg; + break; + default: + err = -EINVAL; + goto out; + } + break; + default: + err = -EINVAL; + goto out; + } + } + ax25_rt = ax25_rt->next; + } + +out: + write_unlock(&ax25_route_lock); + return err; +} + +int ax25_rt_ioctl(unsigned int cmd, void __user *arg) +{ + struct ax25_route_opt_struct rt_option; + struct ax25_routes_struct route; + + switch (cmd) { + case SIOCADDRT: + if (copy_from_user(&route, arg, sizeof(route))) + return -EFAULT; + return ax25_rt_add(&route); + + case SIOCDELRT: + if (copy_from_user(&route, arg, sizeof(route))) + return -EFAULT; + return ax25_rt_del(&route); + + case SIOCAX25OPTRT: + if (copy_from_user(&rt_option, arg, sizeof(rt_option))) + return -EFAULT; + return ax25_rt_opt(&rt_option); + + default: + return -EINVAL; + } +} + +#ifdef CONFIG_PROC_FS + +static void *ax25_rt_seq_start(struct seq_file *seq, loff_t *pos) +{ + struct ax25_route *ax25_rt; + int i = 1; + + read_lock(&ax25_route_lock); + if (*pos == 0) + return SEQ_START_TOKEN; + + for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) { + if (i == *pos) + return ax25_rt; + ++i; + } + + return NULL; +} + +static void *ax25_rt_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + ++*pos; + return (v == SEQ_START_TOKEN) ? ax25_route_list : + ((struct ax25_route *) v)->next; +} + +static void ax25_rt_seq_stop(struct seq_file *seq, void *v) +{ + read_unlock(&ax25_route_lock); +} + +static int ax25_rt_seq_show(struct seq_file *seq, void *v) +{ + if (v == SEQ_START_TOKEN) + seq_puts(seq, "callsign dev mode digipeaters\n"); + else { + struct ax25_route *ax25_rt = v; + const char *callsign; + int i; + + if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0) + callsign = "default"; + else + callsign = ax2asc(&ax25_rt->callsign); + + seq_printf(seq, "%-9s %-4s", + callsign, + ax25_rt->dev ? ax25_rt->dev->name : "???"); + + switch (ax25_rt->ip_mode) { + case 'V': + seq_puts(seq, " vc"); + break; + case 'D': + seq_puts(seq, " dg"); + break; + default: + seq_puts(seq, " *"); + break; + } + + if (ax25_rt->digipeat != NULL) + for (i = 0; i < ax25_rt->digipeat->ndigi; i++) + seq_printf(seq, " %s", ax2asc(&ax25_rt->digipeat->calls[i])); + + seq_puts(seq, "\n"); + } + return 0; +} + +static struct seq_operations ax25_rt_seqops = { + .start = ax25_rt_seq_start, + .next = ax25_rt_seq_next, + .stop = ax25_rt_seq_stop, + .show = ax25_rt_seq_show, +}; + +static int ax25_rt_info_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &ax25_rt_seqops); +} + +struct file_operations ax25_route_fops = { + .owner = THIS_MODULE, + .open = ax25_rt_info_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +#endif + +/* + * Find AX.25 route + * + * Only routes with a refernce rout of zero can be destroyed. + */ +static ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev) +{ + ax25_route *ax25_spe_rt = NULL; + ax25_route *ax25_def_rt = NULL; + ax25_route *ax25_rt; + + read_lock(&ax25_route_lock); + /* + * Bind to the physical interface we heard them on, or the default + * route if none is found; + */ + for (ax25_rt = ax25_route_list; ax25_rt != NULL; ax25_rt = ax25_rt->next) { + if (dev == NULL) { + if (ax25cmp(&ax25_rt->callsign, addr) == 0 && ax25_rt->dev != NULL) + ax25_spe_rt = ax25_rt; + if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0 && ax25_rt->dev != NULL) + ax25_def_rt = ax25_rt; + } else { + if (ax25cmp(&ax25_rt->callsign, addr) == 0 && ax25_rt->dev == dev) + ax25_spe_rt = ax25_rt; + if (ax25cmp(&ax25_rt->callsign, &null_ax25_address) == 0 && ax25_rt->dev == dev) + ax25_def_rt = ax25_rt; + } + } + + ax25_rt = ax25_def_rt; + if (ax25_spe_rt != NULL) + ax25_rt = ax25_spe_rt; + + if (ax25_rt != NULL) + atomic_inc(&ax25_rt->ref); + + read_unlock(&ax25_route_lock); + + return ax25_rt; +} + +/* + * Adjust path: If you specify a default route and want to connect + * a target on the digipeater path but w/o having a special route + * set before, the path has to be truncated from your target on. + */ +static inline void ax25_adjust_path(ax25_address *addr, ax25_digi *digipeat) +{ + int k; + + for (k = 0; k < digipeat->ndigi; k++) { + if (ax25cmp(addr, &digipeat->calls[k]) == 0) + break; + } + + digipeat->ndigi = k; +} + + +/* + * Find which interface to use. + */ +int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr) +{ + ax25_route *ax25_rt; + ax25_address *call; + int err; + + if ((ax25_rt = ax25_get_route(addr, NULL)) == NULL) + return -EHOSTUNREACH; + + if ((ax25->ax25_dev = ax25_dev_ax25dev(ax25_rt->dev)) == NULL) { + err = -EHOSTUNREACH; + goto put; + } + + if ((call = ax25_findbyuid(current->euid)) == NULL) { + if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) { + err = -EPERM; + goto put; + } + call = (ax25_address *)ax25->ax25_dev->dev->dev_addr; + } + + ax25->source_addr = *call; + + if (ax25_rt->digipeat != NULL) { + if ((ax25->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { + err = -ENOMEM; + goto put; + } + memcpy(ax25->digipeat, ax25_rt->digipeat, sizeof(ax25_digi)); + ax25_adjust_path(addr, ax25->digipeat); + } + + if (ax25->sk != NULL) { + bh_lock_sock(ax25->sk); + sock_reset_flag(ax25->sk, SOCK_ZAPPED); + bh_unlock_sock(ax25->sk); + } + +put: + ax25_put_route(ax25_rt); + + return 0; +} + +ax25_route *ax25_rt_find_route(ax25_route * route, ax25_address *addr, + struct net_device *dev) +{ + ax25_route *ax25_rt; + + if ((ax25_rt = ax25_get_route(addr, dev))) + return ax25_rt; + + route->next = NULL; + atomic_set(&route->ref, 1); + route->callsign = *addr; + route->dev = dev; + route->digipeat = NULL; + route->ip_mode = ' '; + + return route; +} + +struct sk_buff *ax25_rt_build_path(struct sk_buff *skb, ax25_address *src, + ax25_address *dest, ax25_digi *digi) +{ + struct sk_buff *skbn; + unsigned char *bp; + int len; + + len = digi->ndigi * AX25_ADDR_LEN; + + if (skb_headroom(skb) < len) { + if ((skbn = skb_realloc_headroom(skb, len)) == NULL) { + printk(KERN_CRIT "AX.25: ax25_dg_build_path - out of memory\n"); + return NULL; + } + + if (skb->sk != NULL) + skb_set_owner_w(skbn, skb->sk); + + kfree_skb(skb); + + skb = skbn; + } + + bp = skb_push(skb, len); + + ax25_addr_build(bp, src, dest, digi, AX25_COMMAND, AX25_MODULUS); + + return skb; +} + +/* + * Free all memory associated with routing structures. + */ +void __exit ax25_rt_free(void) +{ + ax25_route *s, *ax25_rt = ax25_route_list; + + write_lock(&ax25_route_lock); + while (ax25_rt != NULL) { + s = ax25_rt; + ax25_rt = ax25_rt->next; + + if (s->digipeat != NULL) + kfree(s->digipeat); + + kfree(s); + } + write_unlock(&ax25_route_lock); +} |