1/* Linux multicast routing support
  2 * Common logic shared by IPv4 [ipmr] and IPv6 [ip6mr] implementation
  3 */
  4
  5#include <linux/mroute_base.h>
  6
  7/* Sets everything common except 'dev', since that is done under locking */
  8void vif_device_init(struct vif_device *v,
  9		     struct net_device *dev,
 10		     unsigned long rate_limit,
 11		     unsigned char threshold,
 12		     unsigned short flags,
 13		     unsigned short get_iflink_mask)
 14{
 15	v->dev = NULL;
 16	v->bytes_in = 0;
 17	v->bytes_out = 0;
 18	v->pkt_in = 0;
 19	v->pkt_out = 0;
 20	v->rate_limit = rate_limit;
 21	v->flags = flags;
 22	v->threshold = threshold;
 23	if (v->flags & get_iflink_mask)
 24		v->link = dev_get_iflink(dev);
 25	else
 26		v->link = dev->ifindex;
 27}
 28EXPORT_SYMBOL(vif_device_init);
 29
 30struct mr_table *
 31mr_table_alloc(struct net *net, u32 id,
 32	       struct mr_table_ops *ops,
 33	       void (*expire_func)(struct timer_list *t),
 34	       void (*table_set)(struct mr_table *mrt,
 35				 struct net *net))
 36{
 37	struct mr_table *mrt;
 38
 39	mrt = kzalloc(sizeof(*mrt), GFP_KERNEL);
 40	if (!mrt)
 41		return NULL;
 42	mrt->id = id;
 43	write_pnet(&mrt->net, net);
 44
 45	mrt->ops = *ops;
 46	if (rhltable_init(&mrt->mfc_hash, mrt->ops.rht_params)) {
 47		kfree(mrt);
 48		return NULL;
 49	}
 50	INIT_LIST_HEAD(&mrt->mfc_cache_list);
 51	INIT_LIST_HEAD(&mrt->mfc_unres_queue);
 52
 53	timer_setup(&mrt->ipmr_expire_timer, expire_func, 0);
 54
 55	mrt->mroute_reg_vif_num = -1;
 56	table_set(mrt, net);
 57	return mrt;
 58}
 59EXPORT_SYMBOL(mr_table_alloc);
 60
 61void *mr_mfc_find_parent(struct mr_table *mrt, void *hasharg, int parent)
 62{
 63	struct rhlist_head *tmp, *list;
 64	struct mr_mfc *c;
 65
 66	list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
 67	rhl_for_each_entry_rcu(c, tmp, list, mnode)
 68		if (parent == -1 || parent == c->mfc_parent)
 69			return c;
 70
 71	return NULL;
 72}
 73EXPORT_SYMBOL(mr_mfc_find_parent);
 74
 75void *mr_mfc_find_any_parent(struct mr_table *mrt, int vifi)
 76{
 77	struct rhlist_head *tmp, *list;
 78	struct mr_mfc *c;
 79
 80	list = rhltable_lookup(&mrt->mfc_hash, mrt->ops.cmparg_any,
 81			       *mrt->ops.rht_params);
 82	rhl_for_each_entry_rcu(c, tmp, list, mnode)
 83		if (c->mfc_un.res.ttls[vifi] < 255)
 84			return c;
 85
 86	return NULL;
 87}
 88EXPORT_SYMBOL(mr_mfc_find_any_parent);
 89
 90void *mr_mfc_find_any(struct mr_table *mrt, int vifi, void *hasharg)
 91{
 92	struct rhlist_head *tmp, *list;
 93	struct mr_mfc *c, *proxy;
 94
 95	list = rhltable_lookup(&mrt->mfc_hash, hasharg, *mrt->ops.rht_params);
 96	rhl_for_each_entry_rcu(c, tmp, list, mnode) {
 97		if (c->mfc_un.res.ttls[vifi] < 255)
 98			return c;
 99
100		/* It's ok if the vifi is part of the static tree */
101		proxy = mr_mfc_find_any_parent(mrt, c->mfc_parent);
102		if (proxy && proxy->mfc_un.res.ttls[vifi] < 255)
103			return c;
104	}
105
106	return mr_mfc_find_any_parent(mrt, vifi);
107}
108EXPORT_SYMBOL(mr_mfc_find_any);
109
110#ifdef CONFIG_PROC_FS
111void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter, loff_t pos)
112{
113	struct mr_table *mrt = iter->mrt;
114
115	for (iter->ct = 0; iter->ct < mrt->maxvif; ++iter->ct) {
116		if (!VIF_EXISTS(mrt, iter->ct))
117			continue;
118		if (pos-- == 0)
119			return &mrt->vif_table[iter->ct];
120	}
121	return NULL;
122}
123EXPORT_SYMBOL(mr_vif_seq_idx);
124
125void *mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
126{
127	struct mr_vif_iter *iter = seq->private;
128	struct net *net = seq_file_net(seq);
129	struct mr_table *mrt = iter->mrt;
130
131	++*pos;
132	if (v == SEQ_START_TOKEN)
133		return mr_vif_seq_idx(net, iter, 0);
134
135	while (++iter->ct < mrt->maxvif) {
136		if (!VIF_EXISTS(mrt, iter->ct))
137			continue;
138		return &mrt->vif_table[iter->ct];
139	}
140	return NULL;
141}
142EXPORT_SYMBOL(mr_vif_seq_next);
143
144void *mr_mfc_seq_idx(struct net *net,
145		     struct mr_mfc_iter *it, loff_t pos)
146{
147	struct mr_table *mrt = it->mrt;
148	struct mr_mfc *mfc;
149
150	rcu_read_lock();
151	it->cache = &mrt->mfc_cache_list;
152	list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
153		if (pos-- == 0)
154			return mfc;
155	rcu_read_unlock();
156
157	spin_lock_bh(it->lock);
158	it->cache = &mrt->mfc_unres_queue;
159	list_for_each_entry(mfc, it->cache, list)
160		if (pos-- == 0)
161			return mfc;
162	spin_unlock_bh(it->lock);
163
164	it->cache = NULL;
165	return NULL;
166}
167EXPORT_SYMBOL(mr_mfc_seq_idx);
168
169void *mr_mfc_seq_next(struct seq_file *seq, void *v,
170		      loff_t *pos)
171{
172	struct mr_mfc_iter *it = seq->private;
173	struct net *net = seq_file_net(seq);
174	struct mr_table *mrt = it->mrt;
175	struct mr_mfc *c = v;
176
177	++*pos;
178
179	if (v == SEQ_START_TOKEN)
180		return mr_mfc_seq_idx(net, seq->private, 0);
181
182	if (c->list.next != it->cache)
183		return list_entry(c->list.next, struct mr_mfc, list);
184
185	if (it->cache == &mrt->mfc_unres_queue)
186		goto end_of_list;
187
188	/* exhausted cache_array, show unresolved */
189	rcu_read_unlock();
190	it->cache = &mrt->mfc_unres_queue;
191
192	spin_lock_bh(it->lock);
193	if (!list_empty(it->cache))
194		return list_first_entry(it->cache, struct mr_mfc, list);
195
196end_of_list:
197	spin_unlock_bh(it->lock);
198	it->cache = NULL;
199
200	return NULL;
201}
202EXPORT_SYMBOL(mr_mfc_seq_next);
203#endif
204
205int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
206		   struct mr_mfc *c, struct rtmsg *rtm)
207{
208	struct rta_mfc_stats mfcs;
209	struct nlattr *mp_attr;
210	struct rtnexthop *nhp;
211	unsigned long lastuse;
212	int ct;
213
214	/* If cache is unresolved, don't try to parse IIF and OIF */
215	if (c->mfc_parent >= MAXVIFS) {
216		rtm->rtm_flags |= RTNH_F_UNRESOLVED;
217		return -ENOENT;
218	}
219
220	if (VIF_EXISTS(mrt, c->mfc_parent) &&
221	    nla_put_u32(skb, RTA_IIF,
222			mrt->vif_table[c->mfc_parent].dev->ifindex) < 0)
223		return -EMSGSIZE;
224
225	if (c->mfc_flags & MFC_OFFLOAD)
226		rtm->rtm_flags |= RTNH_F_OFFLOAD;
227
228	mp_attr = nla_nest_start(skb, RTA_MULTIPATH);
229	if (!mp_attr)
230		return -EMSGSIZE;
231
232	for (ct = c->mfc_un.res.minvif; ct < c->mfc_un.res.maxvif; ct++) {
233		if (VIF_EXISTS(mrt, ct) && c->mfc_un.res.ttls[ct] < 255) {
234			struct vif_device *vif;
235
236			nhp = nla_reserve_nohdr(skb, sizeof(*nhp));
237			if (!nhp) {
238				nla_nest_cancel(skb, mp_attr);
239				return -EMSGSIZE;
240			}
241
242			nhp->rtnh_flags = 0;
243			nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
244			vif = &mrt->vif_table[ct];
245			nhp->rtnh_ifindex = vif->dev->ifindex;
246			nhp->rtnh_len = sizeof(*nhp);
247		}
248	}
249
250	nla_nest_end(skb, mp_attr);
251
252	lastuse = READ_ONCE(c->mfc_un.res.lastuse);
253	lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
254
255	mfcs.mfcs_packets = c->mfc_un.res.pkt;
256	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
257	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
258	if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
259	    nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
260			      RTA_PAD))
261		return -EMSGSIZE;
262
263	rtm->rtm_type = RTN_MULTICAST;
264	return 1;
265}
266EXPORT_SYMBOL(mr_fill_mroute);
267
268int mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb,
269		     struct mr_table *(*iter)(struct net *net,
270					      struct mr_table *mrt),
271		     int (*fill)(struct mr_table *mrt,
272				 struct sk_buff *skb,
273				 u32 portid, u32 seq, struct mr_mfc *c,
274				 int cmd, int flags),
275		     spinlock_t *lock)
276{
277	unsigned int t = 0, e = 0, s_t = cb->args[0], s_e = cb->args[1];
278	struct net *net = sock_net(skb->sk);
279	struct mr_table *mrt;
280	struct mr_mfc *mfc;
281
282	rcu_read_lock();
283	for (mrt = iter(net, NULL); mrt; mrt = iter(net, mrt)) {
284		if (t < s_t)
285			goto next_table;
286		list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list) {
287			if (e < s_e)
288				goto next_entry;
289			if (fill(mrt, skb, NETLINK_CB(cb->skb).portid,
290				 cb->nlh->nlmsg_seq, mfc,
291				 RTM_NEWROUTE, NLM_F_MULTI) < 0)
292				goto done;
293next_entry:
294			e++;
295		}
296		e = 0;
297		s_e = 0;
298
299		spin_lock_bh(lock);
300		list_for_each_entry(mfc, &mrt->mfc_unres_queue, list) {
301			if (e < s_e)
302				goto next_entry2;
303			if (fill(mrt, skb, NETLINK_CB(cb->skb).portid,
304				 cb->nlh->nlmsg_seq, mfc,
305				 RTM_NEWROUTE, NLM_F_MULTI) < 0) {
306				spin_unlock_bh(lock);
307				goto done;
308			}
309next_entry2:
310			e++;
311		}
312		spin_unlock_bh(lock);
313		e = 0;
314		s_e = 0;
315next_table:
316		t++;
317	}
318done:
319	rcu_read_unlock();
320
321	cb->args[1] = e;
322	cb->args[0] = t;
323
324	return skb->len;
325}
326EXPORT_SYMBOL(mr_rtm_dumproute);
327
328int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
329	    int (*rules_dump)(struct net *net,
330			      struct notifier_block *nb),
331	    struct mr_table *(*mr_iter)(struct net *net,
332					struct mr_table *mrt),
333	    rwlock_t *mrt_lock)
334{
335	struct mr_table *mrt;
336	int err;
337
338	err = rules_dump(net, nb);
339	if (err)
340		return err;
341
342	for (mrt = mr_iter(net, NULL); mrt; mrt = mr_iter(net, mrt)) {
343		struct vif_device *v = &mrt->vif_table[0];
344		struct mr_mfc *mfc;
345		int vifi;
346
347		/* Notifiy on table VIF entries */
348		read_lock(mrt_lock);
349		for (vifi = 0; vifi < mrt->maxvif; vifi++, v++) {
350			if (!v->dev)
351				continue;
352
353			mr_call_vif_notifier(nb, net, family,
354					     FIB_EVENT_VIF_ADD,
355					     v, vifi, mrt->id);
356		}
357		read_unlock(mrt_lock);
358
359		/* Notify on table MFC entries */
360		list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
361			mr_call_mfc_notifier(nb, net, family,
362					     FIB_EVENT_ENTRY_ADD,
363					     mfc, mrt->id);
364	}
365
366	return 0;
367}
368EXPORT_SYMBOL(mr_dump);