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 struct ipx_interface *ipxitf_find_using_net(__be32 net);
24 extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
25 struct sk_buff *skb, int copy);
26 extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
27 struct sk_buff *skb, int copy);
28
ipxrtr_lookup(__be32 net)29 struct ipx_route *ipxrtr_lookup(__be32 net)
30 {
31 struct ipx_route *r;
32
33 read_lock_bh(&ipx_routes_lock);
34 list_for_each_entry(r, &ipx_routes, node)
35 if (r->ir_net == net) {
36 ipxrtr_hold(r);
37 goto unlock;
38 }
39 r = NULL;
40 unlock:
41 read_unlock_bh(&ipx_routes_lock);
42 return r;
43 }
44
45 /*
46 * Caller must hold a reference to intrfc
47 */
ipxrtr_add_route(__be32 network,struct ipx_interface * intrfc,unsigned char * node)48 int ipxrtr_add_route(__be32 network, struct ipx_interface *intrfc,
49 unsigned char *node)
50 {
51 struct ipx_route *rt;
52 int rc;
53
54 /* Get a route structure; either existing or create */
55 rt = ipxrtr_lookup(network);
56 if (!rt) {
57 rt = kmalloc(sizeof(*rt), GFP_ATOMIC);
58 rc = -EAGAIN;
59 if (!rt)
60 goto out;
61
62 atomic_set(&rt->refcnt, 1);
63 ipxrtr_hold(rt);
64 write_lock_bh(&ipx_routes_lock);
65 list_add(&rt->node, &ipx_routes);
66 write_unlock_bh(&ipx_routes_lock);
67 } else {
68 rc = -EEXIST;
69 if (intrfc == ipx_internal_net)
70 goto out_put;
71 }
72
73 rt->ir_net = network;
74 rt->ir_intrfc = intrfc;
75 if (!node) {
76 memset(rt->ir_router_node, '\0', IPX_NODE_LEN);
77 rt->ir_routed = 0;
78 } else {
79 memcpy(rt->ir_router_node, node, IPX_NODE_LEN);
80 rt->ir_routed = 1;
81 }
82
83 rc = 0;
84 out_put:
85 ipxrtr_put(rt);
86 out:
87 return rc;
88 }
89
ipxrtr_del_routes(struct ipx_interface * intrfc)90 void ipxrtr_del_routes(struct ipx_interface *intrfc)
91 {
92 struct ipx_route *r, *tmp;
93
94 write_lock_bh(&ipx_routes_lock);
95 list_for_each_entry_safe(r, tmp, &ipx_routes, node)
96 if (r->ir_intrfc == intrfc) {
97 list_del(&r->node);
98 ipxrtr_put(r);
99 }
100 write_unlock_bh(&ipx_routes_lock);
101 }
102
ipxrtr_create(struct ipx_route_definition * rd)103 static int ipxrtr_create(struct ipx_route_definition *rd)
104 {
105 struct ipx_interface *intrfc;
106 int rc = -ENETUNREACH;
107
108 /* Find the appropriate interface */
109 intrfc = ipxitf_find_using_net(rd->ipx_router_network);
110 if (!intrfc)
111 goto out;
112 rc = ipxrtr_add_route(rd->ipx_network, intrfc, rd->ipx_router_node);
113 ipxitf_put(intrfc);
114 out:
115 return rc;
116 }
117
ipxrtr_delete(__be32 net)118 static int ipxrtr_delete(__be32 net)
119 {
120 struct ipx_route *r, *tmp;
121 int rc;
122
123 write_lock_bh(&ipx_routes_lock);
124 list_for_each_entry_safe(r, tmp, &ipx_routes, node)
125 if (r->ir_net == net) {
126 /* Directly connected; can't lose route */
127 rc = -EPERM;
128 if (!r->ir_routed)
129 goto out;
130 list_del(&r->node);
131 ipxrtr_put(r);
132 rc = 0;
133 goto out;
134 }
135 rc = -ENOENT;
136 out:
137 write_unlock_bh(&ipx_routes_lock);
138 return rc;
139 }
140
141 /*
142 * The skb has to be unshared, we'll end up calling ipxitf_send, that'll
143 * modify the packet
144 */
ipxrtr_route_skb(struct sk_buff * skb)145 int ipxrtr_route_skb(struct sk_buff *skb)
146 {
147 struct ipxhdr *ipx = ipx_hdr(skb);
148 struct ipx_route *r = ipxrtr_lookup(IPX_SKB_CB(skb)->ipx_dest_net);
149
150 if (!r) { /* no known route */
151 kfree_skb(skb);
152 return 0;
153 }
154
155 ipxitf_hold(r->ir_intrfc);
156 ipxitf_send(r->ir_intrfc, skb, r->ir_routed ?
157 r->ir_router_node : ipx->ipx_dest.node);
158 ipxitf_put(r->ir_intrfc);
159 ipxrtr_put(r);
160
161 return 0;
162 }
163
164 /*
165 * Route an outgoing frame from a socket.
166 */
ipxrtr_route_packet(struct sock * sk,struct sockaddr_ipx * usipx,struct msghdr * msg,size_t len,int noblock)167 int ipxrtr_route_packet(struct sock *sk, struct sockaddr_ipx *usipx,
168 struct msghdr *msg, size_t len, int noblock)
169 {
170 struct sk_buff *skb;
171 struct ipx_sock *ipxs = ipx_sk(sk);
172 struct ipx_interface *intrfc;
173 struct ipxhdr *ipx;
174 size_t size;
175 int ipx_offset;
176 struct ipx_route *rt = NULL;
177 int rc;
178
179 /* Find the appropriate interface on which to send packet */
180 if (!usipx->sipx_network && ipx_primary_net) {
181 usipx->sipx_network = ipx_primary_net->if_netnum;
182 intrfc = ipx_primary_net;
183 } else {
184 rt = ipxrtr_lookup(usipx->sipx_network);
185 rc = -ENETUNREACH;
186 if (!rt)
187 goto out;
188 intrfc = rt->ir_intrfc;
189 }
190
191 ipxitf_hold(intrfc);
192 ipx_offset = intrfc->if_ipx_offset;
193 size = sizeof(struct ipxhdr) + len + ipx_offset;
194
195 skb = sock_alloc_send_skb(sk, size, noblock, &rc);
196 if (!skb)
197 goto out_put;
198
199 skb_reserve(skb, ipx_offset);
200 skb->sk = sk;
201
202 /* Fill in IPX header */
203 skb_reset_network_header(skb);
204 skb_reset_transport_header(skb);
205 skb_put(skb, sizeof(struct ipxhdr));
206 ipx = ipx_hdr(skb);
207 ipx->ipx_pktsize = htons(len + sizeof(struct ipxhdr));
208 IPX_SKB_CB(skb)->ipx_tctrl = 0;
209 ipx->ipx_type = usipx->sipx_type;
210
211 IPX_SKB_CB(skb)->last_hop.index = -1;
212 #ifdef CONFIG_IPX_INTERN
213 IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
214 memcpy(ipx->ipx_source.node, ipxs->node, IPX_NODE_LEN);
215 #else
216 rc = ntohs(ipxs->port);
217 if (rc == 0x453 || rc == 0x452) {
218 /* RIP/SAP special handling for mars_nwe */
219 IPX_SKB_CB(skb)->ipx_source_net = intrfc->if_netnum;
220 memcpy(ipx->ipx_source.node, intrfc->if_node, IPX_NODE_LEN);
221 } else {
222 IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
223 memcpy(ipx->ipx_source.node, ipxs->intrfc->if_node,
224 IPX_NODE_LEN);
225 }
226 #endif /* CONFIG_IPX_INTERN */
227 ipx->ipx_source.sock = ipxs->port;
228 IPX_SKB_CB(skb)->ipx_dest_net = usipx->sipx_network;
229 memcpy(ipx->ipx_dest.node, usipx->sipx_node, IPX_NODE_LEN);
230 ipx->ipx_dest.sock = usipx->sipx_port;
231
232 rc = memcpy_from_msg(skb_put(skb, len), msg, len);
233 if (rc) {
234 kfree_skb(skb);
235 goto out_put;
236 }
237
238 /* Apply checksum. Not allowed on 802.3 links. */
239 if (sk->sk_no_check_tx ||
240 intrfc->if_dlink_type == htons(IPX_FRAME_8023))
241 ipx->ipx_checksum = htons(0xFFFF);
242 else
243 ipx->ipx_checksum = ipx_cksum(ipx, len + sizeof(struct ipxhdr));
244
245 rc = ipxitf_send(intrfc, skb, (rt && rt->ir_routed) ?
246 rt->ir_router_node : ipx->ipx_dest.node);
247 out_put:
248 ipxitf_put(intrfc);
249 if (rt)
250 ipxrtr_put(rt);
251 out:
252 return rc;
253 }
254
255 /*
256 * We use a normal struct rtentry for route handling
257 */
ipxrtr_ioctl(unsigned int cmd,void __user * arg)258 int ipxrtr_ioctl(unsigned int cmd, void __user *arg)
259 {
260 struct rtentry rt; /* Use these to behave like 'other' stacks */
261 struct sockaddr_ipx *sg, *st;
262 int rc = -EFAULT;
263
264 if (copy_from_user(&rt, arg, sizeof(rt)))
265 goto out;
266
267 sg = (struct sockaddr_ipx *)&rt.rt_gateway;
268 st = (struct sockaddr_ipx *)&rt.rt_dst;
269
270 rc = -EINVAL;
271 if (!(rt.rt_flags & RTF_GATEWAY) || /* Direct routes are fixed */
272 sg->sipx_family != AF_IPX ||
273 st->sipx_family != AF_IPX)
274 goto out;
275
276 switch (cmd) {
277 case SIOCDELRT:
278 rc = ipxrtr_delete(st->sipx_network);
279 break;
280 case SIOCADDRT: {
281 struct ipx_route_definition f;
282 f.ipx_network = st->sipx_network;
283 f.ipx_router_network = sg->sipx_network;
284 memcpy(f.ipx_router_node, sg->sipx_node, IPX_NODE_LEN);
285 rc = ipxrtr_create(&f);
286 break;
287 }
288 }
289
290 out:
291 return rc;
292 }
293