1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * 4 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) 5 */ 6 #include <linux/errno.h> 7 #include <linux/types.h> 8 #include <linux/socket.h> 9 #include <linux/slab.h> 10 #include <linux/in.h> 11 #include <linux/kernel.h> 12 #include <linux/timer.h> 13 #include <linux/string.h> 14 #include <linux/sockios.h> 15 #include <linux/net.h> 16 #include <linux/spinlock.h> 17 #include <net/ax25.h> 18 #include <linux/inet.h> 19 #include <linux/netdevice.h> 20 #include <linux/if_arp.h> 21 #include <linux/skbuff.h> 22 #include <net/sock.h> 23 #include <linux/uaccess.h> 24 #include <linux/fcntl.h> 25 #include <linux/mm.h> 26 #include <linux/interrupt.h> 27 #include <linux/init.h> 28 29 ax25_dev *ax25_dev_list; 30 DEFINE_SPINLOCK(ax25_dev_lock); 31 32 ax25_dev *ax25_addr_ax25dev(ax25_address *addr) 33 { 34 ax25_dev *ax25_dev, *res = NULL; 35 36 spin_lock_bh(&ax25_dev_lock); 37 for (ax25_dev = ax25_dev_list; ax25_dev != NULL; ax25_dev = ax25_dev->next) 38 if (ax25cmp(addr, (const ax25_address *)ax25_dev->dev->dev_addr) == 0) { 39 res = ax25_dev; 40 } 41 spin_unlock_bh(&ax25_dev_lock); 42 43 return res; 44 } 45 46 /* 47 * This is called when an interface is brought up. These are 48 * reasonable defaults. 49 */ 50 void ax25_dev_device_up(struct net_device *dev) 51 { 52 ax25_dev *ax25_dev; 53 54 if ((ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_ATOMIC)) == NULL) { 55 printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n"); 56 return; 57 } 58 59 dev->ax25_ptr = ax25_dev; 60 ax25_dev->dev = dev; 61 dev_hold_track(dev, &ax25_dev->dev_tracker, GFP_ATOMIC); 62 ax25_dev->forward = NULL; 63 64 ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE; 65 ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE; 66 ax25_dev->values[AX25_VALUES_BACKOFF] = AX25_DEF_BACKOFF; 67 ax25_dev->values[AX25_VALUES_CONMODE] = AX25_DEF_CONMODE; 68 ax25_dev->values[AX25_VALUES_WINDOW] = AX25_DEF_WINDOW; 69 ax25_dev->values[AX25_VALUES_EWINDOW] = AX25_DEF_EWINDOW; 70 ax25_dev->values[AX25_VALUES_T1] = AX25_DEF_T1; 71 ax25_dev->values[AX25_VALUES_T2] = AX25_DEF_T2; 72 ax25_dev->values[AX25_VALUES_T3] = AX25_DEF_T3; 73 ax25_dev->values[AX25_VALUES_IDLE] = AX25_DEF_IDLE; 74 ax25_dev->values[AX25_VALUES_N2] = AX25_DEF_N2; 75 ax25_dev->values[AX25_VALUES_PACLEN] = AX25_DEF_PACLEN; 76 ax25_dev->values[AX25_VALUES_PROTOCOL] = AX25_DEF_PROTOCOL; 77 ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT; 78 79 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER) 80 ax25_ds_setup_timer(ax25_dev); 81 #endif 82 83 spin_lock_bh(&ax25_dev_lock); 84 ax25_dev->next = ax25_dev_list; 85 ax25_dev_list = ax25_dev; 86 spin_unlock_bh(&ax25_dev_lock); 87 88 ax25_register_dev_sysctl(ax25_dev); 89 } 90 91 void ax25_dev_device_down(struct net_device *dev) 92 { 93 ax25_dev *s, *ax25_dev; 94 95 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 96 return; 97 98 ax25_unregister_dev_sysctl(ax25_dev); 99 100 spin_lock_bh(&ax25_dev_lock); 101 102 #ifdef CONFIG_AX25_DAMA_SLAVE 103 ax25_ds_del_timer(ax25_dev); 104 #endif 105 106 /* 107 * Remove any packet forwarding that points to this device. 108 */ 109 for (s = ax25_dev_list; s != NULL; s = s->next) 110 if (s->forward == dev) 111 s->forward = NULL; 112 113 if ((s = ax25_dev_list) == ax25_dev) { 114 ax25_dev_list = s->next; 115 spin_unlock_bh(&ax25_dev_lock); 116 dev->ax25_ptr = NULL; 117 dev_put_track(dev, &ax25_dev->dev_tracker); 118 kfree(ax25_dev); 119 return; 120 } 121 122 while (s != NULL && s->next != NULL) { 123 if (s->next == ax25_dev) { 124 s->next = ax25_dev->next; 125 spin_unlock_bh(&ax25_dev_lock); 126 dev->ax25_ptr = NULL; 127 dev_put_track(dev, &ax25_dev->dev_tracker); 128 kfree(ax25_dev); 129 return; 130 } 131 132 s = s->next; 133 } 134 spin_unlock_bh(&ax25_dev_lock); 135 dev->ax25_ptr = NULL; 136 } 137 138 int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd) 139 { 140 ax25_dev *ax25_dev, *fwd_dev; 141 142 if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL) 143 return -EINVAL; 144 145 switch (cmd) { 146 case SIOCAX25ADDFWD: 147 if ((fwd_dev = ax25_addr_ax25dev(&fwd->port_to)) == NULL) 148 return -EINVAL; 149 if (ax25_dev->forward != NULL) 150 return -EINVAL; 151 ax25_dev->forward = fwd_dev->dev; 152 break; 153 154 case SIOCAX25DELFWD: 155 if (ax25_dev->forward == NULL) 156 return -EINVAL; 157 ax25_dev->forward = NULL; 158 break; 159 160 default: 161 return -EINVAL; 162 } 163 164 return 0; 165 } 166 167 struct net_device *ax25_fwd_dev(struct net_device *dev) 168 { 169 ax25_dev *ax25_dev; 170 171 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 172 return dev; 173 174 if (ax25_dev->forward == NULL) 175 return dev; 176 177 return ax25_dev->forward; 178 } 179 180 /* 181 * Free all memory associated with device structures. 182 */ 183 void __exit ax25_dev_free(void) 184 { 185 ax25_dev *s, *ax25_dev; 186 187 spin_lock_bh(&ax25_dev_lock); 188 ax25_dev = ax25_dev_list; 189 while (ax25_dev != NULL) { 190 s = ax25_dev; 191 dev_put_track(ax25_dev->dev, &ax25_dev->dev_tracker); 192 ax25_dev = ax25_dev->next; 193 kfree(s); 194 } 195 ax25_dev_list = NULL; 196 spin_unlock_bh(&ax25_dev_lock); 197 } 198