xref: /openbmc/linux/net/rose/rose_loopback.c (revision e190bfe5)
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 
18 static struct sk_buff_head loopback_queue;
19 static struct timer_list loopback_timer;
20 
21 static void rose_set_loopback_timer(void);
22 
23 void rose_loopback_init(void)
24 {
25 	skb_queue_head_init(&loopback_queue);
26 
27 	init_timer(&loopback_timer);
28 }
29 
30 static int rose_loopback_running(void)
31 {
32 	return timer_pending(&loopback_timer);
33 }
34 
35 int 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 
53 static void rose_loopback_timer(unsigned long);
54 
55 static 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 
66 static 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 		lci_i     = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
77 		frametype = skb->data[2];
78 		dest      = (rose_address *)(skb->data + 4);
79 		lci_o     = ROSE_DEFAULT_MAXVC + 1 - lci_i;
80 
81 		skb_reset_transport_header(skb);
82 
83 		sk = rose_find_socket(lci_o, rose_loopback_neigh);
84 		if (sk) {
85 			if (rose_process_rx_frame(sk, skb) == 0)
86 				kfree_skb(skb);
87 			continue;
88 		}
89 
90 		if (frametype == ROSE_CALL_REQUEST) {
91 			if ((dev = rose_dev_get(dest)) != NULL) {
92 				if (rose_rx_call_request(skb, dev, rose_loopback_neigh, lci_o) == 0)
93 					kfree_skb(skb);
94 			} else {
95 				kfree_skb(skb);
96 			}
97 		} else {
98 			kfree_skb(skb);
99 		}
100 	}
101 }
102 
103 void __exit rose_loopback_clear(void)
104 {
105 	struct sk_buff *skb;
106 
107 	del_timer(&loopback_timer);
108 
109 	while ((skb = skb_dequeue(&loopback_queue)) != NULL) {
110 		skb->sk = NULL;
111 		kfree_skb(skb);
112 	}
113 }
114