Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog
[linux-2.6] / net / ipx / ipx_route.c
1 /*
2  *      Implements the IPX routing routines.
3  *      Code moved from af_ipx.c.
4  *
5  *      Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 2003
6  *
7  *      See net/ipx/ChangeLog.
8  */
9
10 #include <linux/config.h>
11 #include <linux/list.h>
12 #include <linux/route.h>
13 #include <linux/spinlock.h>
14
15 #include <net/ipx.h>
16 #include <net/sock.h>
17
18 LIST_HEAD(ipx_routes);
19 DEFINE_RWLOCK(ipx_routes_lock);
20
21 extern struct ipx_interface *ipx_internal_net;
22
23 extern __u16 ipx_cksum(struct ipxhdr *packet, int length);
24 extern struct ipx_interface *ipxitf_find_using_net(__u32 net);
25 extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
26                                struct sk_buff *skb, int copy);
27 extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
28                                struct sk_buff *skb, int copy);
29 extern int ipxitf_send(struct ipx_interface *intrfc, struct sk_buff *skb,
30                        char *node);
31 extern struct ipx_interface *ipxitf_find_using_net(__u32 net);
32
33 struct ipx_route *ipxrtr_lookup(__u32 net)
34 {
35         struct ipx_route *r;
36
37         read_lock_bh(&ipx_routes_lock);
38         list_for_each_entry(r, &ipx_routes, node)
39                 if (r->ir_net == net) {
40                         ipxrtr_hold(r);
41                         goto unlock;
42                 }
43         r = NULL;
44 unlock:
45         read_unlock_bh(&ipx_routes_lock);
46         return r;
47 }
48
49 /*
50  * Caller must hold a reference to intrfc
51  */
52 int ipxrtr_add_route(__u32 network, struct ipx_interface *intrfc,
53                      unsigned char *node)
54 {
55         struct ipx_route *rt;
56         int rc;
57
58         /* Get a route structure; either existing or create */
59         rt = ipxrtr_lookup(network);
60         if (!rt) {
61                 rt = kmalloc(sizeof(*rt), GFP_ATOMIC);
62                 rc = -EAGAIN;
63                 if (!rt)
64                         goto out;
65
66                 atomic_set(&rt->refcnt, 1);
67                 ipxrtr_hold(rt);
68                 write_lock_bh(&ipx_routes_lock);
69                 list_add(&rt->node, &ipx_routes);
70                 write_unlock_bh(&ipx_routes_lock);
71         } else {
72                 rc = -EEXIST;
73                 if (intrfc == ipx_internal_net)
74                         goto out_put;
75         }
76
77         rt->ir_net      = network;
78         rt->ir_intrfc   = intrfc;
79         if (!node) {
80                 memset(rt->ir_router_node, '\0', IPX_NODE_LEN);
81                 rt->ir_routed = 0;
82         } else {
83                 memcpy(rt->ir_router_node, node, IPX_NODE_LEN);
84                 rt->ir_routed = 1;
85         }
86
87         rc = 0;
88 out_put:
89         ipxrtr_put(rt);
90 out:
91         return rc;
92 }
93
94 void ipxrtr_del_routes(struct ipx_interface *intrfc)
95 {
96         struct ipx_route *r, *tmp;
97
98         write_lock_bh(&ipx_routes_lock);
99         list_for_each_entry_safe(r, tmp, &ipx_routes, node)
100                 if (r->ir_intrfc == intrfc) {
101                         list_del(&r->node);
102                         ipxrtr_put(r);
103                 }
104         write_unlock_bh(&ipx_routes_lock);
105 }
106
107 static int ipxrtr_create(struct ipx_route_definition *rd)
108 {
109         struct ipx_interface *intrfc;
110         int rc = -ENETUNREACH;
111
112         /* Find the appropriate interface */
113         intrfc = ipxitf_find_using_net(rd->ipx_router_network);
114         if (!intrfc)
115                 goto out;
116         rc = ipxrtr_add_route(rd->ipx_network, intrfc, rd->ipx_router_node);
117         ipxitf_put(intrfc);
118 out:
119         return rc;
120 }
121
122 static int ipxrtr_delete(__u32 net)
123 {
124         struct ipx_route *r, *tmp;
125         int rc;
126
127         write_lock_bh(&ipx_routes_lock);
128         list_for_each_entry_safe(r, tmp, &ipx_routes, node)
129                 if (r->ir_net == net) {
130                         /* Directly connected; can't lose route */
131                         rc = -EPERM;
132                         if (!r->ir_routed)
133                                 goto out;
134                         list_del(&r->node);
135                         ipxrtr_put(r);
136                         rc = 0;
137                         goto out;
138                 }
139         rc = -ENOENT;
140 out:
141         write_unlock_bh(&ipx_routes_lock);
142         return rc;
143 }
144
145 /*
146  * The skb has to be unshared, we'll end up calling ipxitf_send, that'll
147  * modify the packet
148  */
149 int ipxrtr_route_skb(struct sk_buff *skb)
150 {
151         struct ipxhdr *ipx = ipx_hdr(skb);
152         struct ipx_route *r = ipxrtr_lookup(IPX_SKB_CB(skb)->ipx_dest_net);
153
154         if (!r) {       /* no known route */
155                 kfree_skb(skb);
156                 return 0;
157         }
158
159         ipxitf_hold(r->ir_intrfc);
160         ipxitf_send(r->ir_intrfc, skb, r->ir_routed ?
161                         r->ir_router_node : ipx->ipx_dest.node);
162         ipxitf_put(r->ir_intrfc);
163         ipxrtr_put(r);
164
165         return 0;
166 }
167
168 /*
169  * Route an outgoing frame from a socket.
170  */
171 int ipxrtr_route_packet(struct sock *sk, struct sockaddr_ipx *usipx,
172                         struct iovec *iov, size_t len, int noblock)
173 {
174         struct sk_buff *skb;
175         struct ipx_sock *ipxs = ipx_sk(sk);
176         struct ipx_interface *intrfc;
177         struct ipxhdr *ipx;
178         size_t size;
179         int ipx_offset;
180         struct ipx_route *rt = NULL;
181         int rc;
182
183         /* Find the appropriate interface on which to send packet */
184         if (!usipx->sipx_network && ipx_primary_net) {
185                 usipx->sipx_network = ipx_primary_net->if_netnum;
186                 intrfc = ipx_primary_net;
187         } else {
188                 rt = ipxrtr_lookup(usipx->sipx_network);
189                 rc = -ENETUNREACH;
190                 if (!rt)
191                         goto out;
192                 intrfc = rt->ir_intrfc;
193         }
194
195         ipxitf_hold(intrfc);
196         ipx_offset = intrfc->if_ipx_offset;
197         size = sizeof(struct ipxhdr) + len + ipx_offset;
198
199         skb = sock_alloc_send_skb(sk, size, noblock, &rc);
200         if (!skb)
201                 goto out_put;
202
203         skb_reserve(skb, ipx_offset);
204         skb->sk = sk;
205
206         /* Fill in IPX header */
207         skb->h.raw = skb->nh.raw = skb_put(skb, sizeof(struct ipxhdr));
208         ipx = ipx_hdr(skb);
209         ipx->ipx_pktsize = htons(len + sizeof(struct ipxhdr));
210         IPX_SKB_CB(skb)->ipx_tctrl = 0;
211         ipx->ipx_type    = usipx->sipx_type;
212
213         IPX_SKB_CB(skb)->last_hop.index = -1;
214 #ifdef CONFIG_IPX_INTERN
215         IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
216         memcpy(ipx->ipx_source.node, ipxs->node, IPX_NODE_LEN);
217 #else
218         rc = ntohs(ipxs->port);
219         if (rc == 0x453 || rc == 0x452) {
220                 /* RIP/SAP special handling for mars_nwe */
221                 IPX_SKB_CB(skb)->ipx_source_net = intrfc->if_netnum;
222                 memcpy(ipx->ipx_source.node, intrfc->if_node, IPX_NODE_LEN);
223         } else {
224                 IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
225                 memcpy(ipx->ipx_source.node, ipxs->intrfc->if_node,
226                         IPX_NODE_LEN);
227         }
228 #endif  /* CONFIG_IPX_INTERN */
229         ipx->ipx_source.sock            = ipxs->port;
230         IPX_SKB_CB(skb)->ipx_dest_net   = usipx->sipx_network;
231         memcpy(ipx->ipx_dest.node, usipx->sipx_node, IPX_NODE_LEN);
232         ipx->ipx_dest.sock              = usipx->sipx_port;
233
234         rc = memcpy_fromiovec(skb_put(skb, len), iov, len);
235         if (rc) {
236                 kfree_skb(skb);
237                 goto out_put;
238         }       
239
240         /* Apply checksum. Not allowed on 802.3 links. */
241         if (sk->sk_no_check || intrfc->if_dlink_type == IPX_FRAME_8023)
242                 ipx->ipx_checksum = 0xFFFF;
243         else
244                 ipx->ipx_checksum = ipx_cksum(ipx, len + sizeof(struct ipxhdr));
245
246         rc = ipxitf_send(intrfc, skb, (rt && rt->ir_routed) ? 
247                          rt->ir_router_node : ipx->ipx_dest.node);
248 out_put:
249         ipxitf_put(intrfc);
250         if (rt)
251                 ipxrtr_put(rt);
252 out:
253         return rc;
254 }
255
256 /*
257  * We use a normal struct rtentry for route handling
258  */
259 int ipxrtr_ioctl(unsigned int cmd, void __user *arg)
260 {
261         struct rtentry rt;      /* Use these to behave like 'other' stacks */
262         struct sockaddr_ipx *sg, *st;
263         int rc = -EFAULT;
264
265         if (copy_from_user(&rt, arg, sizeof(rt)))
266                 goto out;
267
268         sg = (struct sockaddr_ipx *)&rt.rt_gateway;
269         st = (struct sockaddr_ipx *)&rt.rt_dst;
270
271         rc = -EINVAL;
272         if (!(rt.rt_flags & RTF_GATEWAY) || /* Direct routes are fixed */
273             sg->sipx_family != AF_IPX ||
274             st->sipx_family != AF_IPX)
275                 goto out;
276
277         switch (cmd) {
278         case SIOCDELRT:
279                 rc = ipxrtr_delete(st->sipx_network);
280                 break;
281         case SIOCADDRT: {
282                 struct ipx_route_definition f;
283                 f.ipx_network           = st->sipx_network;
284                 f.ipx_router_network    = sg->sipx_network;
285                 memcpy(f.ipx_router_node, sg->sipx_node, IPX_NODE_LEN);
286                 rc = ipxrtr_create(&f);
287                 break;
288         }
289         }
290
291 out:
292         return rc;
293 }