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 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 } 113 114 void __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