/* * NET/ROM release 007 * * This code REQUIRES 2.1.15 or higher/ NET3.038 * * This module: * This module 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. * * History * NET/ROM 001 Jonathan(G4KLX) First attempt. * NET/ROM 003 Jonathan(G4KLX) Use SIOCADDRT/SIOCDELRT ioctl values * for NET/ROM routes. * Use '*' for a blank mnemonic in /proc/net/nr_nodes. * Change default quality for new neighbour when same * as node callsign. * Alan Cox(GW4PTS) Added the firewall hooks. * NET/ROM 006 Jonathan(G4KLX) Added the setting of digipeated neighbours. * Tomi(OH2BNS) Routing quality and link failure changes. * Device refcnt fixes. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* For TIOCINQ/OUTQ */ #include #include #include #include #include #include static unsigned int nr_neigh_no = 1; static struct nr_node *nr_node_list; static struct nr_neigh *nr_neigh_list; static void nr_remove_neigh(struct nr_neigh *); /* * Add a new route to a node, and in the process add the node and the * neighbour if it is new. */ static int nr_add_node(ax25_address *nr, const char *mnemonic, ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev, int quality, int obs_count) { struct nr_node *nr_node; struct nr_neigh *nr_neigh; struct nr_route nr_route; struct net_device *tdev; unsigned long flags; int i, found; /* Can't add routes to ourself */ if ((tdev = nr_dev_get(nr)) != NULL) { dev_put(tdev); return -EINVAL; } for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) if (ax25cmp(nr, &nr_node->callsign) == 0) break; for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) if (ax25cmp(ax25, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) break; /* * The L2 link to a neighbour has failed in the past * and now a frame comes from this neighbour. We assume * it was a temporary trouble with the link and reset the * routes now (and not wait for a node broadcast). */ if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) { struct nr_node *node; for (node = nr_node_list; node != NULL; node = node->next) for (i = 0; i < node->count; i++) if (node->routes[i].neighbour == nr_neigh) if (i < node->which) node->which = i; } if (nr_neigh != NULL) nr_neigh->failed = 0; if (quality == 0 && nr_neigh != NULL && nr_node != NULL) return 0; if (nr_neigh == NULL) { if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) return -ENOMEM; nr_neigh->callsign = *ax25; nr_neigh->digipeat = NULL; nr_neigh->ax25 = NULL; nr_neigh->dev = dev; nr_neigh->quality = sysctl_netrom_default_path_quality; nr_neigh->locked = 0; nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; if (ax25_digi != NULL && ax25_digi->ndigi > 0) { if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) { kfree(nr_neigh); return -ENOMEM; } memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi)); } dev_hold(nr_neigh->dev); save_flags(flags); cli(); nr_neigh->next = nr_neigh_list; nr_neigh_list = nr_neigh; restore_flags(flags); } if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked) nr_neigh->quality = quality; if (nr_node == NULL) { if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) return -ENOMEM; nr_node->callsign = *nr; strcpy(nr_node->mnemonic, mnemonic); nr_node->which = 0; nr_node->count = 1; nr_node->routes[0].quality = quality; nr_node->routes[0].obs_count = obs_count; nr_node->routes[0].neighbour = nr_neigh; save_flags(flags); cli(); nr_node->next = nr_node_list; nr_node_list = nr_node; restore_flags(flags); nr_neigh->count++; return 0; } if (quality != 0) strcpy(nr_node->mnemonic, mnemonic); for (found = 0, i = 0; i < nr_node->count; i++) { if (nr_node->routes[i].neighbour == nr_neigh) { nr_node->routes[i].quality = quality; nr_node->routes[i].obs_count = obs_count; found = 1; break; } } if (!found) { /* We have space at the bottom, slot it in */ if (nr_node->count < 3) { nr_node->routes[2] = nr_node->routes[1]; nr_node->routes[1] = nr_node->routes[0]; nr_node->routes[0].quality = quality; nr_node->routes[0].obs_count = obs_count; nr_node->routes[0].neighbour = nr_neigh; nr_node->which++; nr_node->count++; nr_neigh->count++; } else { /* It must be better than the worst */ if (quality > nr_node->routes[2].quality) { nr_node->routes[2].neighbour->count--; if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked) nr_remove_neigh(nr_node->routes[2].neighbour); nr_node->routes[2].quality = quality; nr_node->routes[2].obs_count = obs_count; nr_node->routes[2].neighbour = nr_neigh; nr_neigh->count++; } } } /* Now re-sort the routes in quality order */ switch (nr_node->count) { case 3: if (nr_node->routes[1].quality > nr_node->routes[0].quality) { switch (nr_node->which) { case 0: nr_node->which = 1; break; case 1: nr_node->which = 0; break; default: break; } nr_route = nr_node->routes[0]; nr_node->routes[0] = nr_node->routes[1]; nr_node->routes[1] = nr_route; } if (nr_node->routes[2].quality > nr_node->routes[1].quality) { switch (nr_node->which) { case 1: nr_node->which = 2; break; case 2: nr_node->which = 1; break; default: break; } nr_route = nr_node->routes[1]; nr_node->routes[1] = nr_node->routes[2]; nr_node->routes[2] = nr_route; } case 2: if (nr_node->routes[1].quality > nr_node->routes[0].quality) { switch (nr_node->which) { case 0: nr_node->which = 1; break; case 1: nr_node->which = 0; break; default: break; } nr_route = nr_node->routes[0]; nr_node->routes[0] = nr_node->routes[1]; nr_node->routes[1] = nr_route; } case 1: break; } for (i = 0; i < nr_node->count; i++) { if (nr_node->routes[i].neighbour == nr_neigh) { if (i < nr_node->which) nr_node->which = i; break; } } return 0; } static void nr_remove_node(struct nr_node *nr_node) { struct nr_node *s; unsigned long flags; save_flags(flags); cli(); if ((s = nr_node_list) == nr_node) { nr_node_list = nr_node->next; restore_flags(flags); kfree(nr_node); return; } while (s != NULL && s->next != NULL) { if (s->next == nr_node) { s->next = nr_node->next; restore_flags(flags); kfree(nr_node); return; } s = s->next; } restore_flags(flags); } static void nr_remove_neigh(struct nr_neigh *nr_neigh) { struct nr_neigh *s; unsigned long flags; save_flags(flags); cli(); if ((s = nr_neigh_list) == nr_neigh) { nr_neigh_list = nr_neigh->next; restore_flags(flags); dev_put(nr_neigh->dev); if (nr_neigh->digipeat != NULL) kfree(nr_neigh->digipeat); kfree(nr_neigh); return; } while (s != NULL && s->next != NULL) { if (s->next == nr_neigh) { s->next = nr_neigh->next; restore_flags(flags); dev_put(nr_neigh->dev); if (nr_neigh->digipeat != NULL) kfree(nr_neigh->digipeat); kfree(nr_neigh); return; } s = s->next; } restore_flags(flags); } /* * "Delete" a node. Strictly speaking remove a route to a node. The node * is only deleted if no routes are left to it. */ static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev) { struct nr_node *nr_node; struct nr_neigh *nr_neigh; int i; for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) if (ax25cmp(callsign, &nr_node->callsign) == 0) break; if (nr_node == NULL) return -EINVAL; for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) if (ax25cmp(neighbour, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) break; if (nr_neigh == NULL) return -EINVAL; for (i = 0; i < nr_node->count; i++) { if (nr_node->routes[i].neighbour == nr_neigh) { nr_neigh->count--; if (nr_neigh->count == 0 && !nr_neigh->locked) nr_remove_neigh(nr_neigh); nr_node->count--; if (nr_node->count == 0) { nr_remove_node(nr_node); } else { switch (i) { case 0: nr_node->routes[0] = nr_node->routes[1]; case 1: nr_node->routes[1] = nr_node->routes[2]; case 2: break; } } return 0; } } return -EINVAL; } /* * Lock a neighbour with a quality. */ static int nr_add_neigh(ax25_address *callsign, ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality) { struct nr_neigh *nr_neigh; unsigned long flags; for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) { if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) { nr_neigh->quality = quality; nr_neigh->locked = 1; return 0; } } if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) return -ENOMEM; nr_neigh->callsign = *callsign; nr_neigh->digipeat = NULL; nr_neigh->ax25 = NULL; nr_neigh->dev = dev; nr_neigh->quality = quality; nr_neigh->locked = 1; nr_neigh->count = 0; nr_neigh->number = nr_neigh_no++; nr_neigh->failed = 0; if (ax25_digi != NULL && ax25_digi->ndigi > 0) { if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) { kfree(nr_neigh); return -ENOMEM; } memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi)); } dev_hold(nr_neigh->dev); save_flags(flags); cli(); nr_neigh->next = nr_neigh_list; nr_neigh_list = nr_neigh; restore_flags(flags); return 0; } /* * "Delete" a neighbour. The neighbour is only removed if the number * of nodes that may use it is zero. */ static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality) { struct nr_neigh *nr_neigh; for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) break; if (nr_neigh == NULL) return -EINVAL; nr_neigh->quality = quality; nr_neigh->locked = 0; if (nr_neigh->count == 0) nr_remove_neigh(nr_neigh); return 0; } /* * Decrement the obsolescence count by one. If a route is reduced to a * count of zero, remove it. Also remove any unlocked neighbours with * zero nodes routing via it. */ static int nr_dec_obs(void) { struct nr_neigh *nr_neigh; struct nr_node *s, *nr_node; int i; nr_node = nr_node_list; while (nr_node != NULL) { s = nr_node; nr_node = nr_node->next; for (i = 0; i < s->count; i++) { switch (s->routes[i].obs_count) { case 0: /* A locked entry */ break; case 1: /* From 1 -> 0 */ nr_neigh = s->routes[i].neighbour; nr_neigh->count--; if (nr_neigh->count == 0 && !nr_neigh->locked) nr_remove_neigh(nr_neigh); s->count--; switch (i) { case 0: s->routes[0] = s->routes[1]; case 1: s->routes[1] = s->routes[2]; case 2: break; } break; default: s->routes[i].obs_count--; break; } } if (s->count <= 0) nr_remove_node(s); } return 0; } /* * A device has been removed. Remove its routes and neighbours. */ void nr_rt_device_down(struct net_device *dev) { struct nr_neigh *s, *nr_neigh = nr_neigh_list; struct nr_node *t, *nr_node; int i; while (nr_neigh != NULL) { s = nr_neigh; nr_neigh = nr_neigh->next; if (s->dev == dev) { nr_node = nr_node_list; while (nr_node != NULL) { t = nr_node; nr_node = nr_node->next; for (i = 0; i < t->count; i++) { if (t->routes[i].neighbour == s) { t->count--; switch (i) { case 0: t->routes[0] = t->routes[1]; case 1: t->routes[1] = t->routes[2]; case 2: break; } } } if (t->count <= 0) nr_remove_node(t); } nr_remove_neigh(s); } } } /* * Check that the device given is a valid AX.25 interface that is "up". * Or a valid ethernet interface with an AX.25 callsign binding. */ static struct net_device *nr_ax25_dev_get(char *devname) { struct net_device *dev; if ((dev = dev_get_by_name(devname)) == NULL) return NULL; if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25) return dev; dev_put(dev); return NULL; } /* * Find the first active NET/ROM device, usually "nr0". */ struct net_device *nr_dev_first(void) { struct net_device *dev, *first = NULL; read_lock(&dev_base_lock); for (dev = dev_base; dev != NULL; dev = dev->next) { if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM) if (first == NULL || strncmp(dev->name, first->name, 3) < 0) first = dev; } if (first != NULL) dev_hold(first); read_unlock(&dev_base_lock); return first; } /* * Find the NET/ROM device for the given callsign. */ struct net_device *nr_dev_get(ax25_address *addr) { struct net_device *dev; read_lock(&dev_base_lock); for (dev = dev_base; dev != NULL; dev = dev->next) { if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM && ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) { dev_hold(dev); goto out; } } out: read_unlock(&dev_base_lock); return dev; } static ax25_digi *nr_call_to_digi(int ndigis, ax25_address *digipeaters) { static ax25_digi ax25_digi; int i; if (ndigis == 0) return NULL; for (i = 0; i < ndigis; i++) { ax25_digi.calls[i] = digipeaters[i]; ax25_digi.repeated[i] = 0; } ax25_digi.ndigi = ndigis; ax25_digi.lastrepeat = -1; return &ax25_digi; } /* * Handle the ioctls that control the routing functions. */ int nr_rt_ioctl(unsigned int cmd, void *arg) { struct nr_route_struct nr_route; struct net_device *dev; int ret; switch (cmd) { case SIOCADDRT: if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct))) return -EFAULT; if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL) return -EINVAL; if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS) { dev_put(dev); return -EINVAL; } switch (nr_route.type) { case NETROM_NODE: ret = nr_add_node(&nr_route.callsign, nr_route.mnemonic, &nr_route.neighbour, nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters), dev, nr_route.quality, nr_route.obs_count); break; case NETROM_NEIGH: ret = nr_add_neigh(&nr_route.callsign, nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters), dev, nr_route.quality); break; default: ret = -EINVAL; break; } dev_put(dev); return ret; case SIOCDELRT: if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct))) return -EFAULT; if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL) return -EINVAL; switch (nr_route.type) { case NETROM_NODE: ret = nr_del_node(&nr_route.callsign, &nr_route.neighbour, dev); break; case NETROM_NEIGH: ret = nr_del_neigh(&nr_route.callsign, dev, nr_route.quality); break; default: ret = -EINVAL; break; } dev_put(dev); return ret; case SIOCNRDECOBS: return nr_dec_obs(); default: return -EINVAL; } return 0; } /* * A level 2 link has timed out, therefore it appears to be a poor link, * then don't use that neighbour until it is reset. */ void nr_link_failed(ax25_cb *ax25, int reason) { struct nr_neigh *nr_neigh; struct nr_node *nr_node; for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) if (nr_neigh->ax25 == ax25) break; if (nr_neigh == NULL) return; nr_neigh->ax25 = NULL; if (++nr_neigh->failed < sysctl_netrom_link_fails_count) return; for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) if (nr_node->which < nr_node->count && nr_node->routes[nr_node->which].neighbour == nr_neigh) nr_node->which++; } /* * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb * indicates an internally generated frame. */ int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25) { ax25_address *nr_src, *nr_dest; struct nr_neigh *nr_neigh; struct nr_node *nr_node; struct net_device *dev; unsigned char *dptr; nr_src = (ax25_address *)(skb->data + 0); nr_dest = (ax25_address *)(skb->data + 7); if (ax25 != NULL) nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat, ax25->ax25_dev->dev, 0, sysctl_netrom_obsolescence_count_initialiser); if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */ int ret; if (ax25 == NULL) /* Its from me */ ret = nr_loopback_queue(skb); else ret = nr_rx_frame(skb, dev); dev_put(dev); return ret; } if (!sysctl_netrom_routing_control && ax25 != NULL) return 0; /* Its Time-To-Live has expired */ if (--skb->data[14] == 0) return 0; for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) if (ax25cmp(nr_dest, &nr_node->callsign) == 0) break; if (nr_node == NULL || nr_node->which >= nr_node->count) return 0; nr_neigh = nr_node->routes[nr_node->which].neighbour; if ((dev = nr_dev_first()) == NULL) return 0; dptr = skb_push(skb, 1); *dptr = AX25_P_NETROM; nr_neigh->ax25 = ax25_send_frame(skb, 256, (ax25_address *)dev->dev_addr, &nr_neigh->callsign, nr_neigh->digipeat, nr_neigh->dev); dev_put(dev); return (nr_neigh->ax25 != NULL); } int nr_nodes_get_info(char *buffer, char **start, off_t offset, int length) { struct nr_node *nr_node; int len = 0; off_t pos = 0; off_t begin = 0; int i; cli(); len += sprintf(buffer, "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n"); for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) { len += sprintf(buffer + len, "%-9s %-7s %d %d", ax2asc(&nr_node->callsign), (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic, nr_node->which + 1, nr_node->count); for (i = 0; i < nr_node->count; i++) { len += sprintf(buffer + len, " %3d %d %05d", nr_node->routes[i].quality, nr_node->routes[i].obs_count, nr_node->routes[i].neighbour->number); } len += sprintf(buffer + len, "\n"); pos = begin + len; if (pos < offset) { len = 0; begin = pos; } if (pos > offset + length) break; } sti(); *start = buffer + (offset - begin); len -= (offset - begin); if (len > length) len = length; return len; } int nr_neigh_get_info(char *buffer, char **start, off_t offset, int length) { struct nr_neigh *nr_neigh; int len = 0; off_t pos = 0; off_t begin = 0; int i; cli(); len += sprintf(buffer, "addr callsign dev qual lock count failed digipeaters\n"); for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) { len += sprintf(buffer + len, "%05d %-9s %-4s %3d %d %3d %3d", nr_neigh->number, ax2asc(&nr_neigh->callsign), nr_neigh->dev ? nr_neigh->dev->name : "???", nr_neigh->quality, nr_neigh->locked, nr_neigh->count, nr_neigh->failed); if (nr_neigh->digipeat != NULL) { for (i = 0; i < nr_neigh->digipeat->ndigi; i++) len += sprintf(buffer + len, " %s", ax2asc(&nr_neigh->digipeat->calls[i])); } len += sprintf(buffer + len, "\n"); pos = begin + len; if (pos < offset) { len = 0; begin = pos; } if (pos > offset + length) break; } sti(); *start = buffer + (offset - begin); len -= (offset - begin); if (len > length) len = length; return len; } /* * Free all memory associated with the nodes and routes lists. */ void __exit nr_rt_free(void) { struct nr_neigh *s, *nr_neigh = nr_neigh_list; struct nr_node *t, *nr_node = nr_node_list; while (nr_node != NULL) { t = nr_node; nr_node = nr_node->next; nr_remove_node(t); } while (nr_neigh != NULL) { s = nr_neigh; nr_neigh = nr_neigh->next; nr_remove_neigh(s); } }