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/list.h>
11 #include <linux/route.h>
12 #include <linux/slab.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 __be16 ipx_cksum(struct ipxhdr *packet, int length);
24 extern struct ipx_interface *ipxitf_find_using_net(__be32 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(__be32 net);
32
ipxrtr_lookup(__be32 net)33 struct ipx_route *ipxrtr_lookup(__be32 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 */
ipxrtr_add_route(__be32 network,struct ipx_interface * intrfc,unsigned char * node)52 int ipxrtr_add_route(__be32 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
ipxrtr_del_routes(struct ipx_interface * intrfc)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
ipxrtr_create(struct ipx_route_definition * rd)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
ipxrtr_delete(__be32 net)122 static int ipxrtr_delete(__be32 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 */
ipxrtr_route_skb(struct sk_buff * skb)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 */
ipxrtr_route_packet(struct sock * sk,struct sockaddr_ipx * usipx,struct iovec * iov,size_t len,int noblock)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_reset_network_header(skb);
208 skb_reset_transport_header(skb);
209 skb_put(skb, sizeof(struct ipxhdr));
210 ipx = ipx_hdr(skb);
211 ipx->ipx_pktsize = htons(len + sizeof(struct ipxhdr));
212 IPX_SKB_CB(skb)->ipx_tctrl = 0;
213 ipx->ipx_type = usipx->sipx_type;
214
215 IPX_SKB_CB(skb)->last_hop.index = -1;
216 #ifdef CONFIG_IPX_INTERN
217 IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
218 memcpy(ipx->ipx_source.node, ipxs->node, IPX_NODE_LEN);
219 #else
220 rc = ntohs(ipxs->port);
221 if (rc == 0x453 || rc == 0x452) {
222 /* RIP/SAP special handling for mars_nwe */
223 IPX_SKB_CB(skb)->ipx_source_net = intrfc->if_netnum;
224 memcpy(ipx->ipx_source.node, intrfc->if_node, IPX_NODE_LEN);
225 } else {
226 IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
227 memcpy(ipx->ipx_source.node, ipxs->intrfc->if_node,
228 IPX_NODE_LEN);
229 }
230 #endif /* CONFIG_IPX_INTERN */
231 ipx->ipx_source.sock = ipxs->port;
232 IPX_SKB_CB(skb)->ipx_dest_net = usipx->sipx_network;
233 memcpy(ipx->ipx_dest.node, usipx->sipx_node, IPX_NODE_LEN);
234 ipx->ipx_dest.sock = usipx->sipx_port;
235
236 rc = memcpy_fromiovec(skb_put(skb, len), iov, len);
237 if (rc) {
238 kfree_skb(skb);
239 goto out_put;
240 }
241
242 /* Apply checksum. Not allowed on 802.3 links. */
243 if (sk->sk_no_check || intrfc->if_dlink_type == htons(IPX_FRAME_8023))
244 ipx->ipx_checksum = htons(0xFFFF);
245 else
246 ipx->ipx_checksum = ipx_cksum(ipx, len + sizeof(struct ipxhdr));
247
248 rc = ipxitf_send(intrfc, skb, (rt && rt->ir_routed) ?
249 rt->ir_router_node : ipx->ipx_dest.node);
250 out_put:
251 ipxitf_put(intrfc);
252 if (rt)
253 ipxrtr_put(rt);
254 out:
255 return rc;
256 }
257
258 /*
259 * We use a normal struct rtentry for route handling
260 */
ipxrtr_ioctl(unsigned int cmd,void __user * arg)261 int ipxrtr_ioctl(unsigned int cmd, void __user *arg)
262 {
263 struct rtentry rt; /* Use these to behave like 'other' stacks */
264 struct sockaddr_ipx *sg, *st;
265 int rc = -EFAULT;
266
267 if (copy_from_user(&rt, arg, sizeof(rt)))
268 goto out;
269
270 sg = (struct sockaddr_ipx *)&rt.rt_gateway;
271 st = (struct sockaddr_ipx *)&rt.rt_dst;
272
273 rc = -EINVAL;
274 if (!(rt.rt_flags & RTF_GATEWAY) || /* Direct routes are fixed */
275 sg->sipx_family != AF_IPX ||
276 st->sipx_family != AF_IPX)
277 goto out;
278
279 switch (cmd) {
280 case SIOCDELRT:
281 rc = ipxrtr_delete(st->sipx_network);
282 break;
283 case SIOCADDRT: {
284 struct ipx_route_definition f;
285 f.ipx_network = st->sipx_network;
286 f.ipx_router_network = sg->sipx_network;
287 memcpy(f.ipx_router_node, sg->sipx_node, IPX_NODE_LEN);
288 rc = ipxrtr_create(&f);
289 break;
290 }
291 }
292
293 out:
294 return rc;
295 }
296