1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 */
9#include <linux/types.h>
10#include <linux/slab.h>
11#include <linux/socket.h>
12#include <linux/timer.h>
13#include <net/ax25.h>
14#include <linux/skbuff.h>
15#include <net/rose.h>
16#include <linux/init.h>
17
18static struct sk_buff_head loopback_queue;
19static struct timer_list loopback_timer;
20
21static void rose_set_loopback_timer(void);
22
23void rose_loopback_init(void)
24{
25	skb_queue_head_init(&loopback_queue);
26
27	init_timer(&loopback_timer);
28}
29
30static int rose_loopback_running(void)
31{
32	return timer_pending(&loopback_timer);
33}
34
35int rose_loopback_queue(struct sk_buff *skb, struct rose_neigh *neigh)
36{
37	struct sk_buff *skbn;
38
39	skbn = skb_clone(skb, GFP_ATOMIC);
40
41	kfree_skb(skb);
42
43	if (skbn != NULL) {
44		skb_queue_tail(&loopback_queue, skbn);
45
46		if (!rose_loopback_running())
47			rose_set_loopback_timer();
48	}
49
50	return 1;
51}
52
53static void rose_loopback_timer(unsigned long);
54
55static void rose_set_loopback_timer(void)
56{
57	del_timer(&loopback_timer);
58
59	loopback_timer.data     = 0;
60	loopback_timer.function = &rose_loopback_timer;
61	loopback_timer.expires  = jiffies + 10;
62
63	add_timer(&loopback_timer);
64}
65
66static void rose_loopback_timer(unsigned long param)
67{
68	struct sk_buff *skb;
69	struct net_device *dev;
70	rose_address *dest;
71	struct sock *sk;
72	unsigned short frametype;
73	unsigned int lci_i, lci_o;
74
75	while ((skb = skb_dequeue(&loopback_queue)) != NULL) {
76		if (skb->len < ROSE_MIN_LEN) {
77			kfree_skb(skb);
78			continue;
79		}
80		lci_i     = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
81		frametype = skb->data[2];
82		if (frametype == ROSE_CALL_REQUEST &&
83		    (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
84		     skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
85		     ROSE_CALL_REQ_ADDR_LEN_VAL)) {
86			kfree_skb(skb);
87			continue;
88		}
89		dest      = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
90		lci_o     = ROSE_DEFAULT_MAXVC + 1 - lci_i;
91
92		skb_reset_transport_header(skb);
93
94		sk = rose_find_socket(lci_o, rose_loopback_neigh);
95		if (sk) {
96			if (rose_process_rx_frame(sk, skb) == 0)
97				kfree_skb(skb);
98			continue;
99		}
100
101		if (frametype == ROSE_CALL_REQUEST) {
102			if ((dev = rose_dev_get(dest)) != NULL) {
103				if (rose_rx_call_request(skb, dev, rose_loopback_neigh, lci_o) == 0)
104					kfree_skb(skb);
105			} else {
106				kfree_skb(skb);
107			}
108		} else {
109			kfree_skb(skb);
110		}
111	}
112}
113
114void __exit rose_loopback_clear(void)
115{
116	struct sk_buff *skb;
117
118	del_timer(&loopback_timer);
119
120	while ((skb = skb_dequeue(&loopback_queue)) != NULL) {
121		skb->sk = NULL;
122		kfree_skb(skb);
123	}
124}
125