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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 u32 r_preference;
56 unsigned char r_table;
57 unsigned char r_action;
58 unsigned char r_dst_len;
59 unsigned char r_src_len;
60 u32 r_src;
61 u32 r_srcmask;
62 u32 r_dst;
63 u32 r_dstmask;
64 u32 r_srcmap;
65 u8 r_flags;
66 u8 r_tos;
67#ifdef CONFIG_IP_ROUTE_FWMARK
68 u32 r_fwmark;
69#endif
70 int r_ifindex;
71#ifdef CONFIG_NET_CLS_ROUTE
72 __u32 r_tclassid;
73#endif
74 char r_ifname[IFNAMSIZ];
75};
76
77static struct fib_rule default_rule = { NULL, 0x7FFF, RT_TABLE_DEFAULT, RTN_UNICAST, };
78static struct fib_rule main_rule = { &default_rule, 0x7FFE, RT_TABLE_MAIN, RTN_UNICAST, };
79static struct fib_rule local_rule = { &main_rule, 0, RT_TABLE_LOCAL, RTN_UNICAST, };
80
81static struct fib_rule *fib_rules = &local_rule;
82
83int inet_rtm_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
84{
85 struct rtattr **rta = arg;
86 struct rtmsg *rtm = NLMSG_DATA(nlh);
87 struct fib_rule *r, **rp;
88
89 for (rp=&fib_rules; (r=*rp) != NULL; rp=&r->r_next) {
90 if ((!rta[RTA_SRC-1] || memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 4) == 0) &&
91 rtm->rtm_src_len == r->r_src_len &&
92 rtm->rtm_dst_len == r->r_dst_len &&
93 (!rta[RTA_DST-1] || memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 4) == 0) &&
94 rtm->rtm_tos == r->r_tos &&
95#ifdef CONFIG_IP_ROUTE_FWMARK
96 (!rta[RTA_PROTOINFO-1] || memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
97#endif
98 (!rtm->rtm_type || rtm->rtm_type == r->r_action) &&
99 (!rta[RTA_PRIORITY-1] || memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
100 (!rta[RTA_IIF-1] || strcmp(RTA_DATA(rta[RTA_IIF-1]), r->r_ifname) == 0) &&
101 (!rtm->rtm_table || (r && rtm->rtm_table == r->r_table))) {
102 if (r == &local_rule)
103 return -EPERM;
104
105 *rp = r->r_next;
106 synchronize_bh();
107
108 if (r != &default_rule && r != &main_rule)
109 kfree(r);
110 return 0;
111 }
112 }
113 return -ESRCH;
114}
115
116
117
118static struct fib_table *fib_empty_table(void)
119{
120 int id;
121
122 for (id = 1; id <= RT_TABLE_MAX; id++)
123 if (fib_tables[id] == NULL)
124 return __fib_new_table(id);
125 return NULL;
126}
127
128
129int inet_rtm_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
130{
131 struct rtattr **rta = arg;
132 struct rtmsg *rtm = NLMSG_DATA(nlh);
133 struct fib_rule *r, *new_r, **rp;
134 unsigned char table_id;
135
136 if (rtm->rtm_src_len > 32 || rtm->rtm_dst_len > 32 ||
137 (rtm->rtm_tos & ~IPTOS_TOS_MASK))
138 return -EINVAL;
139
140 if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
141 return -EINVAL;
142
143 table_id = rtm->rtm_table;
144 if (table_id == RT_TABLE_UNSPEC) {
145 struct fib_table *table;
146 if (rtm->rtm_type == RTN_UNICAST || rtm->rtm_type == RTN_NAT) {
147 if ((table = fib_empty_table()) == NULL)
148 return -ENOBUFS;
149 table_id = table->tb_id;
150 }
151 }
152
153 new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
154 if (!new_r)
155 return -ENOMEM;
156 memset(new_r, 0, sizeof(*new_r));
157 if (rta[RTA_SRC-1])
158 memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 4);
159 if (rta[RTA_DST-1])
160 memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 4);
161 if (rta[RTA_GATEWAY-1])
162 memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 4);
163 new_r->r_src_len = rtm->rtm_src_len;
164 new_r->r_dst_len = rtm->rtm_dst_len;
165 new_r->r_srcmask = inet_make_mask(rtm->rtm_src_len);
166 new_r->r_dstmask = inet_make_mask(rtm->rtm_dst_len);
167 new_r->r_tos = rtm->rtm_tos;
168#ifdef CONFIG_IP_ROUTE_FWMARK
169 if (rta[RTA_PROTOINFO-1])
170 memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
171#endif
172 new_r->r_action = rtm->rtm_type;
173 new_r->r_flags = rtm->rtm_flags;
174 if (rta[RTA_PRIORITY-1])
175 memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
176 new_r->r_table = table_id;
177 if (rta[RTA_IIF-1]) {
178 struct device *dev;
179 memcpy(new_r->r_ifname, RTA_DATA(rta[RTA_IIF-1]), IFNAMSIZ);
180 new_r->r_ifname[IFNAMSIZ-1] = 0;
181 new_r->r_ifindex = -1;
182 dev = dev_get(new_r->r_ifname);
183 if (dev)
184 new_r->r_ifindex = dev->ifindex;
185 }
186#ifdef CONFIG_NET_CLS_ROUTE
187 if (rta[RTA_FLOW-1])
188 memcpy(&new_r->r_tclassid, RTA_DATA(rta[RTA_FLOW-1]), 4);
189#endif
190
191 rp = &fib_rules;
192 if (!new_r->r_preference) {
193 r = fib_rules;
194 if (r && (r = r->r_next) != NULL) {
195 rp = &fib_rules->r_next;
196 if (r->r_preference)
197 new_r->r_preference = r->r_preference - 1;
198 }
199 }
200
201 while ( (r = *rp) != NULL ) {
202 if (r->r_preference > new_r->r_preference)
203 break;
204 rp = &r->r_next;
205 }
206
207 new_r->r_next = r;
208 *rp = new_r;
209 return 0;
210}
211
212u32 fib_rules_map_destination(u32 daddr, struct fib_result *res)
213{
214 u32 mask = inet_make_mask(res->prefixlen);
215 return (daddr&~mask)|res->fi->fib_nh->nh_gw;
216}
217
218u32 fib_rules_policy(u32 saddr, struct fib_result *res, unsigned *flags)
219{
220 struct fib_rule *r = res->r;
221
222 if (r->r_action == RTN_NAT) {
223 int addrtype = inet_addr_type(r->r_srcmap);
224
225 if (addrtype == RTN_NAT) {
226
227 saddr = (saddr&~r->r_srcmask)|r->r_srcmap;
228 *flags |= RTCF_SNAT;
229 } else if (addrtype == RTN_LOCAL || r->r_srcmap == 0) {
230
231 saddr = r->r_srcmap;
232 *flags |= RTCF_MASQ;
233 }
234 }
235 return saddr;
236}
237
238#ifdef CONFIG_NET_CLS_ROUTE
239u32 fib_rules_tclass(struct fib_result *res)
240{
241 if (res->r)
242 return res->r->r_tclassid;
243 return 0;
244}
245#endif
246
247
248static void fib_rules_detach(struct device *dev)
249{
250 struct fib_rule *r;
251
252 for (r=fib_rules; r; r=r->r_next) {
253 if (r->r_ifindex == dev->ifindex)
254 r->r_ifindex = -1;
255 }
256}
257
258static void fib_rules_attach(struct device *dev)
259{
260 struct fib_rule *r;
261
262 for (r=fib_rules; r; r=r->r_next) {
263 if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0)
264 r->r_ifindex = dev->ifindex;
265 }
266}
267
268int fib_lookup(const struct rt_key *key, struct fib_result *res)
269{
270 int err;
271 struct fib_rule *r, *policy;
272 struct fib_table *tb;
273
274 u32 daddr = key->dst;
275 u32 saddr = key->src;
276
277FRprintk("Lookup: %08x <- %08x ", key->dst, key->src);
278 for (r = fib_rules; r; r=r->r_next) {
279 if (((saddr^r->r_src) & r->r_srcmask) ||
280 ((daddr^r->r_dst) & r->r_dstmask) ||
281#ifdef CONFIG_IP_ROUTE_TOS
282 (r->r_tos && r->r_tos != key->tos) ||
283#endif
284#ifdef CONFIG_IP_ROUTE_FWMARK
285 (r->r_fwmark && r->r_fwmark != key->fwmark) ||
286#endif
287 (r->r_ifindex && r->r_ifindex != key->iif))
288 continue;
289
290FRprintk("tb %d r %d ", r->r_table, r->r_action);
291 switch (r->r_action) {
292 case RTN_UNICAST:
293 case RTN_NAT:
294 policy = r;
295 break;
296 case RTN_UNREACHABLE:
297 return -ENETUNREACH;
298 default:
299 case RTN_BLACKHOLE:
300 return -EINVAL;
301 case RTN_PROHIBIT:
302 return -EACCES;
303 }
304
305 if ((tb = fib_get_table(r->r_table)) == NULL)
306 continue;
307 err = tb->tb_lookup(tb, key, res);
308 if (err == 0) {
309FRprintk("ok\n");
310 res->r = policy;
311 return 0;
312 }
313 if (err < 0 && err != -EAGAIN)
314 return err;
315 }
316FRprintk("FAILURE\n");
317 return -ENETUNREACH;
318}
319
320void fib_select_default(const struct rt_key *key, struct fib_result *res)
321{
322 if (res->r && res->r->r_action == RTN_UNICAST &&
323 FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) {
324 struct fib_table *tb;
325 if ((tb = fib_get_table(res->r->r_table)) != NULL)
326 tb->tb_select_default(tb, key, res);
327 }
328}
329
330static int fib_rules_event(struct notifier_block *this, unsigned long event, void *ptr)
331{
332 struct device *dev = ptr;
333
334 if (event == NETDEV_UNREGISTER)
335 fib_rules_detach(dev);
336 else if (event == NETDEV_REGISTER)
337 fib_rules_attach(dev);
338 return NOTIFY_DONE;
339}
340
341
342struct notifier_block fib_rules_notifier = {
343 fib_rules_event,
344 NULL,
345 0
346};
347
348#ifdef CONFIG_RTNETLINK
349
350extern __inline__ int inet_fill_rule(struct sk_buff *skb,
351 struct fib_rule *r,
352 struct netlink_callback *cb)
353{
354 struct rtmsg *rtm;
355 struct nlmsghdr *nlh;
356 unsigned char *b = skb->tail;
357
358 nlh = NLMSG_PUT(skb, NETLINK_CREDS(cb->skb)->pid, cb->nlh->nlmsg_seq, RTM_NEWRULE, sizeof(*rtm));
359 rtm = NLMSG_DATA(nlh);
360 rtm->rtm_family = AF_INET;
361 rtm->rtm_dst_len = r->r_dst_len;
362 rtm->rtm_src_len = r->r_src_len;
363 rtm->rtm_tos = r->r_tos;
364#ifdef CONFIG_IP_ROUTE_FWMARK
365 if (r->r_fwmark)
366 RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
367#endif
368 rtm->rtm_table = r->r_table;
369 rtm->rtm_protocol = 0;
370 rtm->rtm_scope = 0;
371 rtm->rtm_type = r->r_action;
372 rtm->rtm_flags = r->r_flags;
373
374 if (r->r_dst_len)
375 RTA_PUT(skb, RTA_DST, 4, &r->r_dst);
376 if (r->r_src_len)
377 RTA_PUT(skb, RTA_SRC, 4, &r->r_src);
378 if (r->r_ifname[0])
379 RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
380 if (r->r_preference)
381 RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
382 if (r->r_srcmap)
383 RTA_PUT(skb, RTA_GATEWAY, 4, &r->r_srcmap);
384#ifdef CONFIG_NET_CLS_ROUTE
385 if (r->r_tclassid)
386 RTA_PUT(skb, RTA_FLOW, 4, &r->r_tclassid);
387#endif
388 nlh->nlmsg_len = skb->tail - b;
389 return skb->len;
390
391nlmsg_failure:
392rtattr_failure:
393 skb_put(skb, b - skb->tail);
394 return -1;
395}
396
397int inet_dump_rules(struct sk_buff *skb, struct netlink_callback *cb)
398{
399 int idx;
400 int s_idx = cb->args[0];
401 struct fib_rule *r;
402
403 for (r=fib_rules, idx=0; r; r = r->r_next, idx++) {
404 if (idx < s_idx)
405 continue;
406 if (inet_fill_rule(skb, r, cb) < 0)
407 break;
408 }
409 cb->args[0] = idx;
410
411 return skb->len;
412}
413
414#endif
415
416__initfunc(void fib_rules_init(void))
417{
418 register_netdevice_notifier(&fib_rules_notifier);
419}
420
