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22#include <linux/config.h>
23#include <asm/uaccess.h>
24#include <asm/system.h>
25#include <asm/bitops.h>
26#include <linux/types.h>
27#include <linux/kernel.h>
28#include <linux/sched.h>
29#include <linux/mm.h>
30#include <linux/string.h>
31#include <linux/socket.h>
32#include <linux/sockios.h>
33#include <linux/errno.h>
34#include <linux/in.h>
35#include <linux/inet.h>
36#include <linux/netdevice.h>
37#include <linux/if_arp.h>
38#include <linux/proc_fs.h>
39#include <linux/skbuff.h>
40#include <linux/netlink.h>
41#include <linux/init.h>
42
43#include <net/ip.h>
44#include <net/protocol.h>
45#include <net/route.h>
46#include <net/tcp.h>
47#include <net/sock.h>
48#include <net/ip_fib.h>
49
50#define FRprintk(a...)
51
52struct fib_rule
53{
54 struct fib_rule *r_next;
55 atomic_t r_clntref;
56 u32 r_preference;
57 unsigned char r_table;
58 unsigned char r_action;
59 unsigned char r_dst_len;
60 unsigned char r_src_len;
61 u32 r_src;
62 u32 r_srcmask;
63 u32 r_dst;
64 u32 r_dstmask;
65 u32 r_srcmap;
66 u8 r_flags;
67 u8 r_tos;
68#ifdef CONFIG_IP_ROUTE_FWMARK
69 u32 r_fwmark;
70#endif
71 int r_ifindex;
72#ifdef CONFIG_NET_CLS_ROUTE
73 __u32 r_tclassid;
74#endif
75 char r_ifname[IFNAMSIZ];
76 int r_dead;
77};
78
79static struct fib_rule default_rule = {
80 .r_clntref = ATOMIC_INIT(2),
81 .r_preference = 0x7FFF,
82 .r_table = RT_TABLE_DEFAULT,
83 .r_action = RTN_UNICAST,
84};
85
86static struct fib_rule main_rule = {
87 .r_next = &default_rule,
88 .r_clntref = ATOMIC_INIT(2),
89 .r_preference = 0x7FFE,
90 .r_table = RT_TABLE_MAIN,
91 .r_action = RTN_UNICAST,
92};
93
94static struct fib_rule local_rule = {
95 .r_next = &main_rule,
96 .r_clntref = ATOMIC_INIT(2),
97 .r_table = RT_TABLE_LOCAL,
98 .r_action = RTN_UNICAST,
99};
100
101static struct fib_rule *fib_rules = &local_rule;
102static rwlock_t fib_rules_lock = RW_LOCK_UNLOCKED;
103
104int inet_rtm_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
105{
106 struct rtattr **rta = arg;
107 struct rtmsg *rtm = NLMSG_DATA(nlh);
108 struct fib_rule *r, **rp;
109 int err = -ESRCH;
110
111 for (rp=&fib_rules; (r=*rp) != NULL; rp=&r->r_next) {
112 if ((!rta[RTA_SRC-1] || memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 4) == 0) &&
113 rtm->rtm_src_len == r->r_src_len &&
114 rtm->rtm_dst_len == r->r_dst_len &&
115 (!rta[RTA_DST-1] || memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 4) == 0) &&
116 rtm->rtm_tos == r->r_tos &&
117#ifdef CONFIG_IP_ROUTE_FWMARK
118 (!rta[RTA_PROTOINFO-1] || memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
119#endif
120 (!rtm->rtm_type || rtm->rtm_type == r->r_action) &&
121 (!rta[RTA_PRIORITY-1] || memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
122 (!rta[RTA_IIF-1] || strcmp(RTA_DATA(rta[RTA_IIF-1]), r->r_ifname) == 0) &&
123 (!rtm->rtm_table || (r && rtm->rtm_table == r->r_table))) {
124 err = -EPERM;
125 if (r == &local_rule)
126 break;
127
128 write_lock_bh(&fib_rules_lock);
129 *rp = r->r_next;
130 r->r_dead = 1;
131 write_unlock_bh(&fib_rules_lock);
132 fib_rule_put(r);
133 err = 0;
134 break;
135 }
136 }
137 return err;
138}
139
140
141
142static struct fib_table *fib_empty_table(void)
143{
144 int id;
145
146 for (id = 1; id <= RT_TABLE_MAX; id++)
147 if (fib_tables[id] == NULL)
148 return __fib_new_table(id);
149 return NULL;
150}
151
152void fib_rule_put(struct fib_rule *r)
153{
154 if (atomic_dec_and_test(&r->r_clntref)) {
155 if (r->r_dead)
156 kfree(r);
157 else
158 printk("Freeing alive rule %p\n", r);
159 }
160}
161
162int inet_rtm_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
163{
164 struct rtattr **rta = arg;
165 struct rtmsg *rtm = NLMSG_DATA(nlh);
166 struct fib_rule *r, *new_r, **rp;
167 unsigned char table_id;
168
169 if (rtm->rtm_src_len > 32 || rtm->rtm_dst_len > 32 ||
170 (rtm->rtm_tos & ~IPTOS_TOS_MASK))
171 return -EINVAL;
172
173 if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
174 return -EINVAL;
175
176 table_id = rtm->rtm_table;
177 if (table_id == RT_TABLE_UNSPEC) {
178 struct fib_table *table;
179 if (rtm->rtm_type == RTN_UNICAST || rtm->rtm_type == RTN_NAT) {
180 if ((table = fib_empty_table()) == NULL)
181 return -ENOBUFS;
182 table_id = table->tb_id;
183 }
184 }
185
186 new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
187 if (!new_r)
188 return -ENOMEM;
189 memset(new_r, 0, sizeof(*new_r));
190 if (rta[RTA_SRC-1])
191 memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 4);
192 if (rta[RTA_DST-1])
193 memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 4);
194 if (rta[RTA_GATEWAY-1])
195 memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 4);
196 new_r->r_src_len = rtm->rtm_src_len;
197 new_r->r_dst_len = rtm->rtm_dst_len;
198 new_r->r_srcmask = inet_make_mask(rtm->rtm_src_len);
199 new_r->r_dstmask = inet_make_mask(rtm->rtm_dst_len);
200 new_r->r_tos = rtm->rtm_tos;
201#ifdef CONFIG_IP_ROUTE_FWMARK
202 if (rta[RTA_PROTOINFO-1])
203 memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
204#endif
205 new_r->r_action = rtm->rtm_type;
206 new_r->r_flags = rtm->rtm_flags;
207 if (rta[RTA_PRIORITY-1])
208 memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
209 new_r->r_table = table_id;
210 if (rta[RTA_IIF-1]) {
211 struct net_device *dev;
212 memcpy(new_r->r_ifname, RTA_DATA(rta[RTA_IIF-1]), IFNAMSIZ);
213 new_r->r_ifname[IFNAMSIZ-1] = 0;
214 new_r->r_ifindex = -1;
215 dev = __dev_get_by_name(new_r->r_ifname);
216 if (dev)
217 new_r->r_ifindex = dev->ifindex;
218 }
219#ifdef CONFIG_NET_CLS_ROUTE
220 if (rta[RTA_FLOW-1])
221 memcpy(&new_r->r_tclassid, RTA_DATA(rta[RTA_FLOW-1]), 4);
222#endif
223
224 rp = &fib_rules;
225 if (!new_r->r_preference) {
226 r = fib_rules;
227 if (r && (r = r->r_next) != NULL) {
228 rp = &fib_rules->r_next;
229 if (r->r_preference)
230 new_r->r_preference = r->r_preference - 1;
231 }
232 }
233
234 while ( (r = *rp) != NULL ) {
235 if (r->r_preference > new_r->r_preference)
236 break;
237 rp = &r->r_next;
238 }
239
240 new_r->r_next = r;
241 atomic_inc(&new_r->r_clntref);
242 write_lock_bh(&fib_rules_lock);
243 *rp = new_r;
244 write_unlock_bh(&fib_rules_lock);
245 return 0;
246}
247
248u32 fib_rules_map_destination(u32 daddr, struct fib_result *res)
249{
250 u32 mask = inet_make_mask(res->prefixlen);
251 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
252}
253
254u32 fib_rules_policy(u32 saddr, struct fib_result *res, unsigned *flags)
255{
256 struct fib_rule *r = res->r;
257
258 if (r->r_action == RTN_NAT) {
259 int addrtype = inet_addr_type(r->r_srcmap);
260
261 if (addrtype == RTN_NAT) {
262
263 saddr = (saddr&~r->r_srcmask)|r->r_srcmap;
264 *flags |= RTCF_SNAT;
265 } else if (addrtype == RTN_LOCAL || r->r_srcmap == 0) {
266
267 saddr = r->r_srcmap;
268 *flags |= RTCF_MASQ;
269 }
270 }
271 return saddr;
272}
273
274#ifdef CONFIG_NET_CLS_ROUTE
275u32 fib_rules_tclass(struct fib_result *res)
276{
277 if (res->r)
278 return res->r->r_tclassid;
279 return 0;
280}
281#endif
282
283
284static void fib_rules_detach(struct net_device *dev)
285{
286 struct fib_rule *r;
287
288 for (r=fib_rules; r; r=r->r_next) {
289 if (r->r_ifindex == dev->ifindex) {
290 write_lock_bh(&fib_rules_lock);
291 r->r_ifindex = -1;
292 write_unlock_bh(&fib_rules_lock);
293 }
294 }
295}
296
297static void fib_rules_attach(struct net_device *dev)
298{
299 struct fib_rule *r;
300
301 for (r=fib_rules; r; r=r->r_next) {
302 if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
303 write_lock_bh(&fib_rules_lock);
304 r->r_ifindex = dev->ifindex;
305 write_unlock_bh(&fib_rules_lock);
306 }
307 }
308}
309
310int fib_lookup(const struct flowi *flp, struct fib_result *res)
311{
312 int err;
313 struct fib_rule *r, *policy;
314 struct fib_table *tb;
315
316 u32 daddr = flp->fl4_dst;
317 u32 saddr = flp->fl4_src;
318
319FRprintk("Lookup: %u.%u.%u.%u <- %u.%u.%u.%u ",
320 NIPQUAD(flp->fl4_dst), NIPQUAD(flp->fl4_src));
321 read_lock(&fib_rules_lock);
322 for (r = fib_rules; r; r=r->r_next) {
323 if (((saddr^r->r_src) & r->r_srcmask) ||
324 ((daddr^r->r_dst) & r->r_dstmask) ||
325#ifdef CONFIG_IP_ROUTE_TOS
326 (r->r_tos && r->r_tos != flp->fl4_tos) ||
327#endif
328#ifdef CONFIG_IP_ROUTE_FWMARK
329 (r->r_fwmark && r->r_fwmark != flp->fl4_fwmark) ||
330#endif
331 (r->r_ifindex && r->r_ifindex != flp->iif))
332 continue;
333
334FRprintk("tb %d r %d ", r->r_table, r->r_action);
335 switch (r->r_action) {
336 case RTN_UNICAST:
337 case RTN_NAT:
338 policy = r;
339 break;
340 case RTN_UNREACHABLE:
341 read_unlock(&fib_rules_lock);
342 return -ENETUNREACH;
343 default:
344 case RTN_BLACKHOLE:
345 read_unlock(&fib_rules_lock);
346 return -EINVAL;
347 case RTN_PROHIBIT:
348 read_unlock(&fib_rules_lock);
349 return -EACCES;
350 }
351
352 if ((tb = fib_get_table(r->r_table)) == NULL)
353 continue;
354 err = tb->tb_lookup(tb, flp, res);
355 if (err == 0) {
356 res->r = policy;
357 if (policy)
358 atomic_inc(&policy->r_clntref);
359 read_unlock(&fib_rules_lock);
360 return 0;
361 }
362 if (err < 0 && err != -EAGAIN) {
363 read_unlock(&fib_rules_lock);
364 return err;
365 }
366 }
367FRprintk("FAILURE\n");
368 read_unlock(&fib_rules_lock);
369 return -ENETUNREACH;
370}
371
372void fib_select_default(const struct flowi *flp, struct fib_result *res)
373{
374 if (res->r && res->r->r_action == RTN_UNICAST &&
375 FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) {
376 struct fib_table *tb;
377 if ((tb = fib_get_table(res->r->r_table)) != NULL)
378 tb->tb_select_default(tb, flp, res);
379 }
380}
381
382static int fib_rules_event(struct notifier_block *this, unsigned long event, void *ptr)
383{
384 struct net_device *dev = ptr;
385
386 if (event == NETDEV_UNREGISTER)
387 fib_rules_detach(dev);
388 else if (event == NETDEV_REGISTER)
389 fib_rules_attach(dev);
390 return NOTIFY_DONE;
391}
392
393
394struct notifier_block fib_rules_notifier = {
395 .notifier_call =fib_rules_event,
396};
397
398static __inline__ int inet_fill_rule(struct sk_buff *skb,
399 struct fib_rule *r,
400 struct netlink_callback *cb)
401{
402 struct rtmsg *rtm;
403 struct nlmsghdr *nlh;
404 unsigned char *b = skb->tail;
405
406 nlh = NLMSG_PUT(skb, NETLINK_CREDS(cb->skb)->pid, cb->nlh->nlmsg_seq, RTM_NEWRULE, sizeof(*rtm));
407 rtm = NLMSG_DATA(nlh);
408 rtm->rtm_family = AF_INET;
409 rtm->rtm_dst_len = r->r_dst_len;
410 rtm->rtm_src_len = r->r_src_len;
411 rtm->rtm_tos = r->r_tos;
412#ifdef CONFIG_IP_ROUTE_FWMARK
413 if (r->r_fwmark)
414 RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
415#endif
416 rtm->rtm_table = r->r_table;
417 rtm->rtm_protocol = 0;
418 rtm->rtm_scope = 0;
419 rtm->rtm_type = r->r_action;
420 rtm->rtm_flags = r->r_flags;
421
422 if (r->r_dst_len)
423 RTA_PUT(skb, RTA_DST, 4, &r->r_dst);
424 if (r->r_src_len)
425 RTA_PUT(skb, RTA_SRC, 4, &r->r_src);
426 if (r->r_ifname[0])
427 RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
428 if (r->r_preference)
429 RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
430 if (r->r_srcmap)
431 RTA_PUT(skb, RTA_GATEWAY, 4, &r->r_srcmap);
432#ifdef CONFIG_NET_CLS_ROUTE
433 if (r->r_tclassid)
434 RTA_PUT(skb, RTA_FLOW, 4, &r->r_tclassid);
435#endif
436 nlh->nlmsg_len = skb->tail - b;
437 return skb->len;
438
439nlmsg_failure:
440rtattr_failure:
441 skb_put(skb, b - skb->tail);
442 return -1;
443}
444
445int inet_dump_rules(struct sk_buff *skb, struct netlink_callback *cb)
446{
447 int idx;
448 int s_idx = cb->args[0];
449 struct fib_rule *r;
450
451 read_lock(&fib_rules_lock);
452 for (r=fib_rules, idx=0; r; r = r->r_next, idx++) {
453 if (idx < s_idx)
454 continue;
455 if (inet_fill_rule(skb, r, cb) < 0)
456 break;
457 }
458 read_unlock(&fib_rules_lock);
459 cb->args[0] = idx;
460
461 return skb->len;
462}
463
464void __init fib_rules_init(void)
465{
466 register_netdevice_notifier(&fib_rules_notifier);
467}
468
