~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/ipv4/fib_rules.c

Version: ~ [ linux-5.6-rc1 ] ~ [ linux-5.5.2 ] ~ [ linux-5.4.17 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.102 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.170 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.213 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.213 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.81 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
  3  *              operating system.  INET is implemented using the  BSD Socket
  4  *              interface as the means of communication with the user level.
  5  *
  6  *              IPv4 Forwarding Information Base: policy rules.
  7  *
  8  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  9  *              Thomas Graf <tgraf@suug.ch>
 10  *
 11  *              This program is free software; you can redistribute it and/or
 12  *              modify it under the terms of the GNU General Public License
 13  *              as published by the Free Software Foundation; either version
 14  *              2 of the License, or (at your option) any later version.
 15  *
 16  * Fixes:
 17  *              Rani Assaf      :       local_rule cannot be deleted
 18  *              Marc Boucher    :       routing by fwmark
 19  */
 20 
 21 #include <linux/types.h>
 22 #include <linux/kernel.h>
 23 #include <linux/netdevice.h>
 24 #include <linux/netlink.h>
 25 #include <linux/inetdevice.h>
 26 #include <linux/init.h>
 27 #include <linux/list.h>
 28 #include <linux/rcupdate.h>
 29 #include <linux/export.h>
 30 #include <net/ip.h>
 31 #include <net/route.h>
 32 #include <net/tcp.h>
 33 #include <net/ip_fib.h>
 34 #include <net/fib_rules.h>
 35 
 36 struct fib4_rule {
 37         struct fib_rule         common;
 38         u8                      dst_len;
 39         u8                      src_len;
 40         u8                      tos;
 41         __be32                  src;
 42         __be32                  srcmask;
 43         __be32                  dst;
 44         __be32                  dstmask;
 45 #ifdef CONFIG_IP_ROUTE_CLASSID
 46         u32                     tclassid;
 47 #endif
 48 };
 49 
 50 int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res)
 51 {
 52         struct fib_lookup_arg arg = {
 53                 .result = res,
 54                 .flags = FIB_LOOKUP_NOREF,
 55         };
 56         int err;
 57 
 58         err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
 59 #ifdef CONFIG_IP_ROUTE_CLASSID
 60         if (arg.rule)
 61                 res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
 62         else
 63                 res->tclassid = 0;
 64 #endif
 65         return err;
 66 }
 67 EXPORT_SYMBOL_GPL(__fib_lookup);
 68 
 69 static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp,
 70                             int flags, struct fib_lookup_arg *arg)
 71 {
 72         int err = -EAGAIN;
 73         struct fib_table *tbl;
 74 
 75         switch (rule->action) {
 76         case FR_ACT_TO_TBL:
 77                 break;
 78 
 79         case FR_ACT_UNREACHABLE:
 80                 err = -ENETUNREACH;
 81                 goto errout;
 82 
 83         case FR_ACT_PROHIBIT:
 84                 err = -EACCES;
 85                 goto errout;
 86 
 87         case FR_ACT_BLACKHOLE:
 88         default:
 89                 err = -EINVAL;
 90                 goto errout;
 91         }
 92 
 93         tbl = fib_get_table(rule->fr_net, rule->table);
 94         if (!tbl)
 95                 goto errout;
 96 
 97         err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *) arg->result, arg->flags);
 98         if (err > 0)
 99                 err = -EAGAIN;
100 errout:
101         return err;
102 }
103 
104 
105 static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
106 {
107         struct fib4_rule *r = (struct fib4_rule *) rule;
108         struct flowi4 *fl4 = &fl->u.ip4;
109         __be32 daddr = fl4->daddr;
110         __be32 saddr = fl4->saddr;
111 
112         if (((saddr ^ r->src) & r->srcmask) ||
113             ((daddr ^ r->dst) & r->dstmask))
114                 return 0;
115 
116         if (r->tos && (r->tos != fl4->flowi4_tos))
117                 return 0;
118 
119         return 1;
120 }
121 
122 static struct fib_table *fib_empty_table(struct net *net)
123 {
124         u32 id;
125 
126         for (id = 1; id <= RT_TABLE_MAX; id++)
127                 if (fib_get_table(net, id) == NULL)
128                         return fib_new_table(net, id);
129         return NULL;
130 }
131 
132 static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
133         FRA_GENERIC_POLICY,
134         [FRA_FLOW]      = { .type = NLA_U32 },
135 };
136 
137 static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
138                                struct fib_rule_hdr *frh,
139                                struct nlattr **tb)
140 {
141         struct net *net = sock_net(skb->sk);
142         int err = -EINVAL;
143         struct fib4_rule *rule4 = (struct fib4_rule *) rule;
144 
145         if (frh->tos & ~IPTOS_TOS_MASK)
146                 goto errout;
147 
148         if (rule->table == RT_TABLE_UNSPEC) {
149                 if (rule->action == FR_ACT_TO_TBL) {
150                         struct fib_table *table;
151 
152                         table = fib_empty_table(net);
153                         if (table == NULL) {
154                                 err = -ENOBUFS;
155                                 goto errout;
156                         }
157 
158                         rule->table = table->tb_id;
159                 }
160         }
161 
162         if (frh->src_len)
163                 rule4->src = nla_get_be32(tb[FRA_SRC]);
164 
165         if (frh->dst_len)
166                 rule4->dst = nla_get_be32(tb[FRA_DST]);
167 
168 #ifdef CONFIG_IP_ROUTE_CLASSID
169         if (tb[FRA_FLOW]) {
170                 rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
171                 if (rule4->tclassid)
172                         net->ipv4.fib_num_tclassid_users++;
173         }
174 #endif
175 
176         rule4->src_len = frh->src_len;
177         rule4->srcmask = inet_make_mask(rule4->src_len);
178         rule4->dst_len = frh->dst_len;
179         rule4->dstmask = inet_make_mask(rule4->dst_len);
180         rule4->tos = frh->tos;
181 
182         net->ipv4.fib_has_custom_rules = true;
183         err = 0;
184 errout:
185         return err;
186 }
187 
188 static void fib4_rule_delete(struct fib_rule *rule)
189 {
190         struct net *net = rule->fr_net;
191 #ifdef CONFIG_IP_ROUTE_CLASSID
192         struct fib4_rule *rule4 = (struct fib4_rule *) rule;
193 
194         if (rule4->tclassid)
195                 net->ipv4.fib_num_tclassid_users--;
196 #endif
197         net->ipv4.fib_has_custom_rules = true;
198 }
199 
200 static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
201                              struct nlattr **tb)
202 {
203         struct fib4_rule *rule4 = (struct fib4_rule *) rule;
204 
205         if (frh->src_len && (rule4->src_len != frh->src_len))
206                 return 0;
207 
208         if (frh->dst_len && (rule4->dst_len != frh->dst_len))
209                 return 0;
210 
211         if (frh->tos && (rule4->tos != frh->tos))
212                 return 0;
213 
214 #ifdef CONFIG_IP_ROUTE_CLASSID
215         if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
216                 return 0;
217 #endif
218 
219         if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC])))
220                 return 0;
221 
222         if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST])))
223                 return 0;
224 
225         return 1;
226 }
227 
228 static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
229                           struct fib_rule_hdr *frh)
230 {
231         struct fib4_rule *rule4 = (struct fib4_rule *) rule;
232 
233         frh->dst_len = rule4->dst_len;
234         frh->src_len = rule4->src_len;
235         frh->tos = rule4->tos;
236 
237         if ((rule4->dst_len &&
238              nla_put_be32(skb, FRA_DST, rule4->dst)) ||
239             (rule4->src_len &&
240              nla_put_be32(skb, FRA_SRC, rule4->src)))
241                 goto nla_put_failure;
242 #ifdef CONFIG_IP_ROUTE_CLASSID
243         if (rule4->tclassid &&
244             nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
245                 goto nla_put_failure;
246 #endif
247         return 0;
248 
249 nla_put_failure:
250         return -ENOBUFS;
251 }
252 
253 static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
254 {
255         return nla_total_size(4) /* dst */
256                + nla_total_size(4) /* src */
257                + nla_total_size(4); /* flow */
258 }
259 
260 static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
261 {
262         rt_cache_flush(ops->fro_net);
263 }
264 
265 static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
266         .family         = AF_INET,
267         .rule_size      = sizeof(struct fib4_rule),
268         .addr_size      = sizeof(u32),
269         .action         = fib4_rule_action,
270         .match          = fib4_rule_match,
271         .configure      = fib4_rule_configure,
272         .delete         = fib4_rule_delete,
273         .compare        = fib4_rule_compare,
274         .fill           = fib4_rule_fill,
275         .default_pref   = fib_default_rule_pref,
276         .nlmsg_payload  = fib4_rule_nlmsg_payload,
277         .flush_cache    = fib4_rule_flush_cache,
278         .nlgroup        = RTNLGRP_IPV4_RULE,
279         .policy         = fib4_rule_policy,
280         .owner          = THIS_MODULE,
281 };
282 
283 static int fib_default_rules_init(struct fib_rules_ops *ops)
284 {
285         int err;
286 
287         err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
288         if (err < 0)
289                 return err;
290         err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
291         if (err < 0)
292                 return err;
293         err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
294         if (err < 0)
295                 return err;
296         return 0;
297 }
298 
299 int __net_init fib4_rules_init(struct net *net)
300 {
301         int err;
302         struct fib_rules_ops *ops;
303 
304         ops = fib_rules_register(&fib4_rules_ops_template, net);
305         if (IS_ERR(ops))
306                 return PTR_ERR(ops);
307 
308         err = fib_default_rules_init(ops);
309         if (err < 0)
310                 goto fail;
311         net->ipv4.rules_ops = ops;
312         net->ipv4.fib_has_custom_rules = false;
313         return 0;
314 
315 fail:
316         /* also cleans all rules already added */
317         fib_rules_unregister(ops);
318         return err;
319 }
320 
321 void __net_exit fib4_rules_exit(struct net *net)
322 {
323         fib_rules_unregister(net->ipv4.rules_ops);
324 }
325 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp