cregit-Linux how code gets into the kernel

Release 4.8 net/netrom/nr_route.c

Directory: net/netrom
/*
 * 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 Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
 */
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.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 <net/arp.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <net/netrom.h>
#include <linux/seq_file.h>
#include <linux/export.h>


static unsigned int nr_neigh_no = 1;

static HLIST_HEAD(nr_node_list);
static DEFINE_SPINLOCK(nr_node_list_lock);
static HLIST_HEAD(nr_neigh_list);
static DEFINE_SPINLOCK(nr_neigh_list_lock);


static struct nr_node *nr_node_get(ax25_address *callsign) { struct nr_node *found = NULL; struct nr_node *nr_node; spin_lock_bh(&nr_node_list_lock); nr_node_for_each(nr_node, &nr_node_list) if (ax25cmp(callsign, &nr_node->callsign) == 0) { nr_node_hold(nr_node); found = nr_node; break; } spin_unlock_bh(&nr_node_list_lock); return found; }

Contributors

PersonTokensPropCommitsCommitProp
jeroen vreekenjeroen vreeken7098.59%150.00%
adrian bunkadrian bunk11.41%150.00%
Total71100.00%2100.00%


static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign, struct net_device *dev) { struct nr_neigh *found = NULL; struct nr_neigh *nr_neigh; spin_lock_bh(&nr_neigh_list_lock); nr_neigh_for_each(nr_neigh, &nr_neigh_list) if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) { nr_neigh_hold(nr_neigh); found = nr_neigh; break; } spin_unlock_bh(&nr_neigh_list_lock); return found; }

Contributors

PersonTokensPropCommitsCommitProp
jeroen vreekenjeroen vreeken7692.68%125.00%
pre-gitpre-git44.88%125.00%
adrian bunkadrian bunk11.22%125.00%
ralf baechleralf baechle11.22%125.00%
Total82100.00%4100.00%

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 __must_check 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; int i, found; struct net_device *odev; if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */ dev_put(odev); return -EINVAL; } nr_node = nr_node_get(nr); nr_neigh = nr_neigh_get_dev(ax25, dev); /* * 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 *nr_nodet; spin_lock_bh(&nr_node_list_lock); nr_node_for_each(nr_nodet, &nr_node_list) { nr_node_lock(nr_nodet); for (i = 0; i < nr_nodet->count; i++) if (nr_nodet->routes[i].neighbour == nr_neigh) if (i < nr_nodet->which) nr_nodet->which = i; nr_node_unlock(nr_nodet); } spin_unlock_bh(&nr_node_list_lock); } if (nr_neigh != NULL) nr_neigh->failed = 0; if (quality == 0 && nr_neigh != NULL && nr_node != NULL) { nr_neigh_put(nr_neigh); nr_node_put(nr_node); return 0; } if (nr_neigh == NULL) { if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) { if (nr_node) nr_node_put(nr_node); 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; atomic_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi), GFP_KERNEL); if (nr_neigh->digipeat == NULL) { kfree(nr_neigh); if (nr_node) nr_node_put(nr_node); return -ENOMEM; } } spin_lock_bh(&nr_neigh_list_lock); hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list); nr_neigh_hold(nr_neigh); spin_unlock_bh(&nr_neigh_list_lock); } 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) { if (nr_neigh) nr_neigh_put(nr_neigh); return -ENOMEM; } nr_node->callsign = *nr; strcpy(nr_node->mnemonic, mnemonic); nr_node->which = 0; nr_node->count = 1; atomic_set(&nr_node->refcount, 1); spin_lock_init(&nr_node->node_lock); nr_node->routes[0].quality = quality; nr_node->routes[0].obs_count = obs_count; nr_node->routes[0].neighbour = nr_neigh; nr_neigh_hold(nr_neigh); nr_neigh->count++; spin_lock_bh(&nr_node_list_lock); hlist_add_head(&nr_node->node_node, &nr_node_list); /* refcount initialized at 1 */ spin_unlock_bh(&nr_node_list_lock); return 0; } nr_node_lock(nr_node); 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_hold(nr_neigh); nr_neigh->count++; } else { /* It must be better than the worst */ if (quality > nr_node->routes[2].quality) { nr_node->routes[2].neighbour->count--; nr_neigh_put(nr_node->routes[2].neighbour); 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_hold(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; } 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; } } nr_neigh_put(nr_neigh); nr_node_unlock(nr_node); nr_node_put(nr_node); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git103582.34%1368.42%
jeroen vreekenjeroen vreeken20015.91%15.26%
arnaldo carvalho de meloarnaldo carvalho de melo90.72%15.26%
ralf baechleralf baechle90.72%315.79%
andrew mortonandrew morton40.32%15.26%
Total1257100.00%19100.00%


static inline void __nr_remove_node(struct nr_node *nr_node) { hlist_del_init(&nr_node->node_node); nr_node_put(nr_node); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1976.00%133.33%
jeroen vreekenjeroen vreeken520.00%133.33%
ralf baechleralf baechle14.00%133.33%
Total25100.00%3100.00%

#define nr_remove_node_locked(__node) \ __nr_remove_node(__node)
static void nr_remove_node(struct nr_node *nr_node) { spin_lock_bh(&nr_node_list_lock); __nr_remove_node(nr_node); spin_unlock_bh(&nr_node_list_lock); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1346.43%125.00%
jeroen vreekenjeroen vreeken1242.86%125.00%
ralf baechleralf baechle310.71%250.00%
Total28100.00%4100.00%


static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh) { hlist_del_init(&nr_neigh->neigh_node); nr_neigh_put(nr_neigh); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1976.00%250.00%
jeroen vreekenjeroen vreeken520.00%125.00%
ralf baechleralf baechle14.00%125.00%
Total25100.00%4100.00%

#define nr_remove_neigh_locked(__neigh) \ __nr_remove_neigh(__neigh)
static void nr_remove_neigh(struct nr_neigh *nr_neigh) { spin_lock_bh(&nr_neigh_list_lock); __nr_remove_neigh(nr_neigh); spin_unlock_bh(&nr_neigh_list_lock); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git1346.43%240.00%
jeroen vreekenjeroen vreeken1242.86%120.00%
ralf baechleralf baechle310.71%240.00%
Total28100.00%5100.00%

/* * "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; nr_node = nr_node_get(callsign); if (nr_node == NULL) return -EINVAL; nr_neigh = nr_neigh_get_dev(neighbour, dev); if (nr_neigh == NULL) { nr_node_put(nr_node); return -EINVAL; } nr_node_lock(nr_node); for (i = 0; i < nr_node->count; i++) { if (nr_node->routes[i].neighbour == nr_neigh) { nr_neigh->count--; nr_neigh_put(nr_neigh); if (nr_neigh->count == 0 && !nr_neigh->locked) nr_remove_neigh(nr_neigh); nr_neigh_put(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; } nr_node_put(nr_node); } nr_node_unlock(nr_node); return 0; } } nr_neigh_put(nr_neigh); nr_node_unlock(nr_node); nr_node_put(nr_node); return -EINVAL; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git18676.23%266.67%
jeroen vreekenjeroen vreeken5823.77%133.33%
Total244100.00%3100.00%

/* * Lock a neighbour with a quality. */
static int __must_check nr_add_neigh(ax25_address *callsign, ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality) { struct nr_neigh *nr_neigh; nr_neigh = nr_neigh_get_dev(callsign, dev); if (nr_neigh) { nr_neigh->quality = quality; nr_neigh->locked = 1; nr_neigh_put(nr_neigh); 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; atomic_set(&nr_neigh->refcount, 1); if (ax25_digi != NULL && ax25_digi->ndigi > 0) { nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi), GFP_KERNEL); if (nr_neigh->digipeat == NULL) { kfree(nr_neigh); return -ENOMEM; } } spin_lock_bh(&nr_neigh_list_lock); hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list); /* refcount is initialized at 1 */ spin_unlock_bh(&nr_neigh_list_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git18680.87%861.54%
jeroen vreekenjeroen vreeken3013.04%17.69%
arnaldo carvalho de meloarnaldo carvalho de melo93.91%17.69%
ralf baechleralf baechle52.17%323.08%
Total230100.00%13100.00%

/* * "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; nr_neigh = nr_neigh_get_dev(callsign, dev); if (nr_neigh == NULL) return -EINVAL; nr_neigh->quality = quality; nr_neigh->locked = 0; if (nr_neigh->count == 0) nr_remove_neigh(nr_neigh); nr_neigh_put(nr_neigh); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git6889.47%266.67%
jeroen vreekenjeroen vreeken810.53%133.33%
Total76100.00%3100.00%

/* * 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; struct hlist_node *nodet; int i; spin_lock_bh(&nr_node_list_lock); nr_node_for_each_safe(s, nodet, &nr_node_list) { nr_node_lock(s); 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--; nr_neigh_put(nr_neigh); 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]; /* Fallthrough */ 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_locked(s); nr_node_unlock(s); } spin_unlock_bh(&nr_node_list_lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git17681.86%250.00%
jeroen vreekenjeroen vreeken3817.67%125.00%
joe perchesjoe perches10.47%125.00%
Total215100.00%4100.00%

/* * A device has been removed. Remove its routes and neighbours. */
void nr_rt_device_down(struct net_device *dev) { struct nr_neigh *s; struct hlist_node *nodet, *node2t; struct nr_node *t; int i; spin_lock_bh(&nr_neigh_list_lock); nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) { if (s->dev == dev) { spin_lock_bh(&nr_node_list_lock); nr_node_for_each_safe(t, node2t, &nr_node_list) { nr_node_lock(t); 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_locked(t); nr_node_unlock(t); } spin_unlock_bh(&nr_node_list_lock); nr_remove_neigh_locked(s); } } spin_unlock_bh(&nr_neigh_list_lock); }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git13670.10%266.67%
jeroen vreekenjeroen vreeken5829.90%133.33%
Total194100.00%3100.00%

/* * 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(&init_net, devname)) == NULL) return NULL; if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25) return dev; dev_put(dev); return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git6095.24%375.00%
eric w. biedermaneric w. biederman34.76%125.00%
Total63100.00%4100.00%

/* * Find the first active NET/ROM device, usually "nr0". */
struct net_device *nr_dev_first(void) { struct net_device *dev, *first = NULL; rcu_read_lock(); for_each_netdev_rcu(&init_net, dev) { if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM) if (first == NULL || strncmp(dev->name, first->name, 3) < 0) first = dev; } if (first) dev_hold(first); rcu_read_unlock(); return first; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git6777.91%342.86%
jeroen vreekenjeroen vreeken910.47%114.29%
eric dumazeteric dumazet55.81%114.29%
pavel emelianovpavel emelianov33.49%114.29%
eric w. biedermaneric w. biederman22.33%114.29%
Total86100.00%7100.00%

/* * Find the NET/ROM device for the given callsign. */
struct net_device *nr_dev_get(ax25_address *addr) { struct net_device *dev; rcu_read_lock(); for_each_netdev_rcu(&init_net, dev) { if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM && ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) { dev_hold(dev); goto out; } } dev = NULL; out: rcu_read_unlock(); return dev; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git6682.50%457.14%
pavel emelianovpavel emelianov78.75%114.29%
eric dumazeteric dumazet56.25%114.29%
eric w. biedermaneric w. biederman22.50%114.29%
Total80100.00%7100.00%


static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis, ax25_address *digipeaters) { int i; if (ndigis == 0) return NULL; for (i = 0; i < ndigis; i++) { digi->calls[i] = digipeaters[i]; digi->repeated[i] = 0; } digi->ndigi = ndigis; digi->lastrepeat = -1; return digi; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git6984.15%266.67%
ralf baechleralf baechle1315.85%133.33%
Total82100.00%3100.00%

/* * Handle the ioctls that control the routing functions. */
int nr_rt_ioctl(unsigned int cmd, void __user *arg) { struct nr_route_struct nr_route; struct net_device *dev; ax25_digi digi; int ret; switch (cmd) { case SIOCADDRT: if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct))) return -EFAULT; if (nr_route.ndigis > AX25_MAX_DIGIS) return -EINVAL; if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL) return -EINVAL; switch (nr_route.type) { case NETROM_NODE: if (strnlen(nr_route.mnemonic, 7) == 7) { ret = -EINVAL; break; } ret = nr_add_node(&nr_route.callsign, nr_route.mnemonic, &nr_route.neighbour, nr_call_to_digi(&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(&digi, nr_route.ndigis, nr_route.digipeaters), dev, nr_route.quality); break; default: ret = -EINVAL; } dev_put(dev); return ret; case SIOCDELRT: if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))