aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipx/ipx_route.c
blob: a394c6fe19a26839e07dbed3f7015224d03c1161 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
/*
 *	Implements the IPX routing routines.
 *	Code moved from af_ipx.c.
 *
 *	Arnaldo Carvalho de Melo <acme@conectiva.com.br>, 2003
 *
 *	See net/ipx/ChangeLog.
 */

#include <linux/config.h>
#include <linux/list.h>
#include <linux/route.h>
#include <linux/spinlock.h>

#include <net/ipx.h>
#include <net/sock.h>

LIST_HEAD(ipx_routes);
DEFINE_RWLOCK(ipx_routes_lock);

extern struct ipx_interface *ipx_internal_net;

extern __u16 ipx_cksum(struct ipxhdr *packet, int length);
extern struct ipx_interface *ipxitf_find_using_net(__u32 net);
extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
			       struct sk_buff *skb, int copy);
extern int ipxitf_demux_socket(struct ipx_interface *intrfc,
			       struct sk_buff *skb, int copy);
extern int ipxitf_send(struct ipx_interface *intrfc, struct sk_buff *skb,
		       char *node);
extern struct ipx_interface *ipxitf_find_using_net(__u32 net);

struct ipx_route *ipxrtr_lookup(__u32 net)
{
	struct ipx_route *r;

	read_lock_bh(&ipx_routes_lock);
	list_for_each_entry(r, &ipx_routes, node)
		if (r->ir_net == net) {
			ipxrtr_hold(r);
			goto unlock;
		}
	r = NULL;
unlock:
	read_unlock_bh(&ipx_routes_lock);
	return r;
}

/*
 * Caller must hold a reference to intrfc
 */
int ipxrtr_add_route(__u32 network, struct ipx_interface *intrfc,
		     unsigned char *node)
{
	struct ipx_route *rt;
	int rc;

	/* Get a route structure; either existing or create */
	rt = ipxrtr_lookup(network);
	if (!rt) {
		rt = kmalloc(sizeof(*rt), GFP_ATOMIC);
		rc = -EAGAIN;
		if (!rt)
			goto out;

		atomic_set(&rt->refcnt, 1);
		ipxrtr_hold(rt);
		write_lock_bh(&ipx_routes_lock);
		list_add(&rt->node, &ipx_routes);
		write_unlock_bh(&ipx_routes_lock);
	} else {
		rc = -EEXIST;
		if (intrfc == ipx_internal_net)
			goto out_put;
	}

	rt->ir_net 	= network;
	rt->ir_intrfc 	= intrfc;
	if (!node) {
		memset(rt->ir_router_node, '\0', IPX_NODE_LEN);
		rt->ir_routed = 0;
	} else {
		memcpy(rt->ir_router_node, node, IPX_NODE_LEN);
		rt->ir_routed = 1;
	}

	rc = 0;
out_put:
	ipxrtr_put(rt);
out:
	return rc;
}

void ipxrtr_del_routes(struct ipx_interface *intrfc)
{
	struct ipx_route *r, *tmp;

	write_lock_bh(&ipx_routes_lock);
	list_for_each_entry_safe(r, tmp, &ipx_routes, node)
		if (r->ir_intrfc == intrfc) {
			list_del(&r->node);
			ipxrtr_put(r);
		}
	write_unlock_bh(&ipx_routes_lock);
}

static int ipxrtr_create(struct ipx_route_definition *rd)
{
	struct ipx_interface *intrfc;
	int rc = -ENETUNREACH;

	/* Find the appropriate interface */
	intrfc = ipxitf_find_using_net(rd->ipx_router_network);
	if (!intrfc)
		goto out;
	rc = ipxrtr_add_route(rd->ipx_network, intrfc, rd->ipx_router_node);
	ipxitf_put(intrfc);
out:
	return rc;
}

static int ipxrtr_delete(__u32 net)
{
	struct ipx_route *r, *tmp;
	int rc;

	write_lock_bh(&ipx_routes_lock);
	list_for_each_entry_safe(r, tmp, &ipx_routes, node)
		if (r->ir_net == net) {
			/* Directly connected; can't lose route */
			rc = -EPERM;
			if (!r->ir_routed)
				goto out;
			list_del(&r->node);
			ipxrtr_put(r);
			rc = 0;
			goto out;
		}
	rc = -ENOENT;
out:
	write_unlock_bh(&ipx_routes_lock);
	return rc;
}

/*
 * The skb has to be unshared, we'll end up calling ipxitf_send, that'll
 * modify the packet
 */
int ipxrtr_route_skb(struct sk_buff *skb)
{
	struct ipxhdr *ipx = ipx_hdr(skb);
	struct ipx_route *r = ipxrtr_lookup(IPX_SKB_CB(skb)->ipx_dest_net);

	if (!r) {	/* no known route */
		kfree_skb(skb);
		return 0;
	}

	ipxitf_hold(r->ir_intrfc);
	ipxitf_send(r->ir_intrfc, skb, r->ir_routed ?
			r->ir_router_node : ipx->ipx_dest.node);
	ipxitf_put(r->ir_intrfc);
	ipxrtr_put(r);

	return 0;
}

/*
 * Route an outgoing frame from a socket.
 */
int ipxrtr_route_packet(struct sock *sk, struct sockaddr_ipx *usipx,
			struct iovec *iov, size_t len, int noblock)
{
	struct sk_buff *skb;
	struct ipx_sock *ipxs = ipx_sk(sk);
	struct ipx_interface *intrfc;
	struct ipxhdr *ipx;
	size_t size;
	int ipx_offset;
	struct ipx_route *rt = NULL;
	int rc;

	/* Find the appropriate interface on which to send packet */
	if (!usipx->sipx_network && ipx_primary_net) {
		usipx->sipx_network = ipx_primary_net->if_netnum;
		intrfc = ipx_primary_net;
	} else {
		rt = ipxrtr_lookup(usipx->sipx_network);
		rc = -ENETUNREACH;
		if (!rt)
			goto out;
		intrfc = rt->ir_intrfc;
	}

	ipxitf_hold(intrfc);
	ipx_offset = intrfc->if_ipx_offset;
	size = sizeof(struct ipxhdr) + len + ipx_offset;

	skb = sock_alloc_send_skb(sk, size, noblock, &rc);
	if (!skb)
		goto out_put;

	skb_reserve(skb, ipx_offset);
	skb->sk = sk;

	/* Fill in IPX header */
	skb->h.raw = skb->nh.raw = skb_put(skb, sizeof(struct ipxhdr));
	ipx = ipx_hdr(skb);
	ipx->ipx_pktsize = htons(len + sizeof(struct ipxhdr));
	IPX_SKB_CB(skb)->ipx_tctrl = 0;
	ipx->ipx_type 	 = usipx->sipx_type;

	IPX_SKB_CB(skb)->last_hop.index = -1;
#ifdef CONFIG_IPX_INTERN
	IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
	memcpy(ipx->ipx_source.node, ipxs->node, IPX_NODE_LEN);
#else
	rc = ntohs(ipxs->port);
	if (rc == 0x453 || rc == 0x452) {
		/* RIP/SAP special handling for mars_nwe */
		IPX_SKB_CB(skb)->ipx_source_net = intrfc->if_netnum;
		memcpy(ipx->ipx_source.node, intrfc->if_node, IPX_NODE_LEN);
	} else {
		IPX_SKB_CB(skb)->ipx_source_net = ipxs->intrfc->if_netnum;
		memcpy(ipx->ipx_source.node, ipxs->intrfc->if_node,
			IPX_NODE_LEN);
	}
#endif	/* CONFIG_IPX_INTERN */
	ipx->ipx_source.sock		= ipxs->port;
	IPX_SKB_CB(skb)->ipx_dest_net	= usipx->sipx_network;
	memcpy(ipx->ipx_dest.node, usipx->sipx_node, IPX_NODE_LEN);
	ipx->ipx_dest.sock		= usipx->sipx_port;

	rc = memcpy_fromiovec(skb_put(skb, len), iov, len);
	if (rc) {
		kfree_skb(skb);
		goto out_put;
	}	

	/* Apply checksum. Not allowed on 802.3 links. */
	if (sk->sk_no_check || intrfc->if_dlink_type == IPX_FRAME_8023)
		ipx->ipx_checksum = 0xFFFF;
	else
		ipx->ipx_checksum = ipx_cksum(ipx, len + sizeof(struct ipxhdr));

	rc = ipxitf_send(intrfc, skb, (rt && rt->ir_routed) ? 
			 rt->ir_router_node : ipx->ipx_dest.node);
out_put:
	ipxitf_put(intrfc);
	if (rt)
		ipxrtr_put(rt);
out:
	return rc;
}

/*
 * We use a normal struct rtentry for route handling
 */
int ipxrtr_ioctl(unsigned int cmd, void __user *arg)
{
	struct rtentry rt;	/* Use these to behave like 'other' stacks */
	struct sockaddr_ipx *sg, *st;
	int rc = -EFAULT;

	if (copy_from_user(&rt, arg, sizeof(rt)))
		goto out;

	sg = (struct sockaddr_ipx *)&rt.rt_gateway;
	st = (struct sockaddr_ipx *)&rt.rt_dst;

	rc = -EINVAL;
	if (!(rt.rt_flags & RTF_GATEWAY) || /* Direct routes are fixed */
	    sg->sipx_family != AF_IPX ||
	    st->sipx_family != AF_IPX)
		goto out;

	switch (cmd) {
	case SIOCDELRT:
		rc = ipxrtr_delete(st->sipx_network);
		break;
	case SIOCADDRT: {
		struct ipx_route_definition f;
		f.ipx_network		= st->sipx_network;
		f.ipx_router_network	= sg->sipx_network;
		memcpy(f.ipx_router_node, sg->sipx_node, IPX_NODE_LEN);
		rc = ipxrtr_create(&f);
		break;
	}
	}

out:
	return rc;
}