Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 
  2 /*
  3  * DECnet       An implementation of the DECnet protocol suite for the LINUX
  4  *              operating system.  DECnet is implemented using the  BSD Socket
  5  *              interface as the means of communication with the user level.
  6  *
  7  *              DECnet Routing Forwarding Information Base (Rules)
  8  *
  9  * Author:      Steve Whitehouse <SteveW@ACM.org>
 10  *              Mostly copied from Alexey Kuznetsov's ipv4/fib_rules.c
 11  *
 12  *
 13  * Changes:
 14  *              Steve Whitehouse <steve@chygwyn.com>
 15  *              Updated for Thomas Graf's generic rules
 16  *
 17  */
 18 #include <linux/net.h>
 19 #include <linux/init.h>
 20 #include <linux/netlink.h>
 21 #include <linux/rtnetlink.h>
 22 #include <linux/netdevice.h>
 23 #include <linux/spinlock.h>
 24 #include <linux/list.h>
 25 #include <linux/rcupdate.h>
 26 #include <net/neighbour.h>
 27 #include <net/dst.h>
 28 #include <net/flow.h>
 29 #include <net/fib_rules.h>
 30 #include <net/dn.h>
 31 #include <net/dn_fib.h>
 32 #include <net/dn_neigh.h>
 33 #include <net/dn_dev.h>
 34 #include <net/dn_route.h>
 35 
 36 static struct fib_rules_ops dn_fib_rules_ops;
 37 
 38 struct dn_fib_rule
 39 {
 40         struct fib_rule         common;
 41         unsigned char           dst_len;
 42         unsigned char           src_len;
 43         __le16                  src;
 44         __le16                  srcmask;
 45         __le16                  dst;
 46         __le16                  dstmask;
 47         __le16                  srcmap;
 48         u8                      flags;
 49 };
 50 
 51 
 52 int dn_fib_lookup(struct flowi *flp, struct dn_fib_res *res)
 53 {
 54         struct fib_lookup_arg arg = {
 55                 .result = res,
 56         };
 57         int err;
 58 
 59         err = fib_rules_lookup(&dn_fib_rules_ops, flp, 0, &arg);
 60         res->r = arg.rule;
 61 
 62         return err;
 63 }
 64 
 65 static int dn_fib_rule_action(struct fib_rule *rule, struct flowi *flp,
 66                               int flags, struct fib_lookup_arg *arg)
 67 {
 68         int err = -EAGAIN;
 69         struct dn_fib_table *tbl;
 70 
 71         switch(rule->action) {
 72         case FR_ACT_TO_TBL:
 73                 break;
 74 
 75         case FR_ACT_UNREACHABLE:
 76                 err = -ENETUNREACH;
 77                 goto errout;
 78 
 79         case FR_ACT_PROHIBIT:
 80                 err = -EACCES;
 81                 goto errout;
 82 
 83         case FR_ACT_BLACKHOLE:
 84         default:
 85                 err = -EINVAL;
 86                 goto errout;
 87         }
 88 
 89         tbl = dn_fib_get_table(rule->table, 0);
 90         if (tbl == NULL)
 91                 goto errout;
 92 
 93         err = tbl->lookup(tbl, flp, (struct dn_fib_res *)arg->result);
 94         if (err > 0)
 95                 err = -EAGAIN;
 96 errout:
 97         return err;
 98 }
 99 
100 static const struct nla_policy dn_fib_rule_policy[FRA_MAX+1] = {
101         FRA_GENERIC_POLICY,
102 };
103 
104 static int dn_fib_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
105 {
106         struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
107         __le16 daddr = fl->fld_dst;
108         __le16 saddr = fl->fld_src;
109 
110         if (((saddr ^ r->src) & r->srcmask) ||
111             ((daddr ^ r->dst) & r->dstmask))
112                 return 0;
113 
114         return 1;
115 }
116 
117 static int dn_fib_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
118                                  struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
119                                  struct nlattr **tb)
120 {
121         int err = -EINVAL;
122         struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
123 
124         if (frh->tos)
125                 goto  errout;
126 
127         if (rule->table == RT_TABLE_UNSPEC) {
128                 if (rule->action == FR_ACT_TO_TBL) {
129                         struct dn_fib_table *table;
130 
131                         table = dn_fib_empty_table();
132                         if (table == NULL) {
133                                 err = -ENOBUFS;
134                                 goto errout;
135                         }
136 
137                         rule->table = table->n;
138                 }
139         }
140 
141         if (frh->src_len)
142                 r->src = nla_get_le16(tb[FRA_SRC]);
143 
144         if (frh->dst_len)
145                 r->dst = nla_get_le16(tb[FRA_DST]);
146 
147         r->src_len = frh->src_len;
148         r->srcmask = dnet_make_mask(r->src_len);
149         r->dst_len = frh->dst_len;
150         r->dstmask = dnet_make_mask(r->dst_len);
151         err = 0;
152 errout:
153         return err;
154 }
155 
156 static int dn_fib_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
157                                struct nlattr **tb)
158 {
159         struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
160 
161         if (frh->src_len && (r->src_len != frh->src_len))
162                 return 0;
163 
164         if (frh->dst_len && (r->dst_len != frh->dst_len))
165                 return 0;
166 
167         if (frh->src_len && (r->src != nla_get_le16(tb[FRA_SRC])))
168                 return 0;
169 
170         if (frh->dst_len && (r->dst != nla_get_le16(tb[FRA_DST])))
171                 return 0;
172 
173         return 1;
174 }
175 
176 unsigned dnet_addr_type(__le16 addr)
177 {
178         struct flowi fl = { .nl_u = { .dn_u = { .daddr = addr } } };
179         struct dn_fib_res res;
180         unsigned ret = RTN_UNICAST;
181         struct dn_fib_table *tb = dn_fib_get_table(RT_TABLE_LOCAL, 0);
182 
183         res.r = NULL;
184 
185         if (tb) {
186                 if (!tb->lookup(tb, &fl, &res)) {
187                         ret = res.type;
188                         dn_fib_res_put(&res);
189                 }
190         }
191         return ret;
192 }
193 
194 static int dn_fib_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
195                             struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
196 {
197         struct dn_fib_rule *r = (struct dn_fib_rule *)rule;
198 
199         frh->family = AF_DECnet;
200         frh->dst_len = r->dst_len;
201         frh->src_len = r->src_len;
202         frh->tos = 0;
203 
204         if (r->dst_len)
205                 NLA_PUT_LE16(skb, FRA_DST, r->dst);
206         if (r->src_len)
207                 NLA_PUT_LE16(skb, FRA_SRC, r->src);
208 
209         return 0;
210 
211 nla_put_failure:
212         return -ENOBUFS;
213 }
214 
215 static u32 dn_fib_rule_default_pref(struct fib_rules_ops *ops)
216 {
217         struct list_head *pos;
218         struct fib_rule *rule;
219 
220         if (!list_empty(&dn_fib_rules_ops.rules_list)) {
221                 pos = dn_fib_rules_ops.rules_list.next;
222                 if (pos->next != &dn_fib_rules_ops.rules_list) {
223                         rule = list_entry(pos->next, struct fib_rule, list);
224                         if (rule->pref)
225                                 return rule->pref - 1;
226                 }
227         }
228 
229         return 0;
230 }
231 
232 static void dn_fib_rule_flush_cache(void)
233 {
234         dn_rt_cache_flush(-1);
235 }
236 
237 static struct fib_rules_ops dn_fib_rules_ops = {
238         .family         = AF_DECnet,
239         .rule_size      = sizeof(struct dn_fib_rule),
240         .addr_size      = sizeof(u16),
241         .action         = dn_fib_rule_action,
242         .match          = dn_fib_rule_match,
243         .configure      = dn_fib_rule_configure,
244         .compare        = dn_fib_rule_compare,
245         .fill           = dn_fib_rule_fill,
246         .default_pref   = dn_fib_rule_default_pref,
247         .flush_cache    = dn_fib_rule_flush_cache,
248         .nlgroup        = RTNLGRP_DECnet_RULE,
249         .policy         = dn_fib_rule_policy,
250         .rules_list     = LIST_HEAD_INIT(dn_fib_rules_ops.rules_list),
251         .owner          = THIS_MODULE,
252         .fro_net        = &init_net,
253 };
254 
255 void __init dn_fib_rules_init(void)
256 {
257         BUG_ON(fib_default_rule_add(&dn_fib_rules_ops, 0x7fff,
258                                     RT_TABLE_MAIN, 0));
259         fib_rules_register(&dn_fib_rules_ops);
260 }
261 
262 void __exit dn_fib_rules_cleanup(void)
263 {
264         fib_rules_unregister(&dn_fib_rules_ops);
265 }
266 
267 
268 
  This page was automatically generated by the LXR engine.