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 ax25_dev_hold(ax25_dev); 41 } 42 spin_unlock_bh(&ax25_dev_lock); 43 44 return res; 45 } 46 47 /* 48 * This is called when an interface is brought up. These are 49 * reasonable defaults. 50 */ 51 void ax25_dev_device_up(struct net_device *dev) 52 { 53 ax25_dev *ax25_dev; 54 55 if ((ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_ATOMIC)) == NULL) { 56 printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n"); 57 return; 58 } 59 60 refcount_set(&ax25_dev->refcount, 1); 61 dev->ax25_ptr = ax25_dev; 62 ax25_dev->dev = dev; 63 dev_hold_track(dev, &ax25_dev->dev_tracker, GFP_ATOMIC); 64 ax25_dev->forward = NULL; 65 ax25_dev->device_up = true; 66 67 ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE; 68 ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE; 69 ax25_dev->values[AX25_VALUES_BACKOFF] = AX25_DEF_BACKOFF; 70 ax25_dev->values[AX25_VALUES_CONMODE] = AX25_DEF_CONMODE; 71 ax25_dev->values[AX25_VALUES_WINDOW] = AX25_DEF_WINDOW; 72 ax25_dev->values[AX25_VALUES_EWINDOW] = AX25_DEF_EWINDOW; 73 ax25_dev->values[AX25_VALUES_T1] = AX25_DEF_T1; 74 ax25_dev->values[AX25_VALUES_T2] = AX25_DEF_T2; 75 ax25_dev->values[AX25_VALUES_T3] = AX25_DEF_T3; 76 ax25_dev->values[AX25_VALUES_IDLE] = AX25_DEF_IDLE; 77 ax25_dev->values[AX25_VALUES_N2] = AX25_DEF_N2; 78 ax25_dev->values[AX25_VALUES_PACLEN] = AX25_DEF_PACLEN; 79 ax25_dev->values[AX25_VALUES_PROTOCOL] = AX25_DEF_PROTOCOL; 80 ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT; 81 82 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER) 83 ax25_ds_setup_timer(ax25_dev); 84 #endif 85 86 spin_lock_bh(&ax25_dev_lock); 87 ax25_dev->next = ax25_dev_list; 88 ax25_dev_list = ax25_dev; 89 spin_unlock_bh(&ax25_dev_lock); 90 ax25_dev_hold(ax25_dev); 91 92 ax25_register_dev_sysctl(ax25_dev); 93 } 94 95 void ax25_dev_device_down(struct net_device *dev) 96 { 97 ax25_dev *s, *ax25_dev; 98 99 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 100 return; 101 102 ax25_unregister_dev_sysctl(ax25_dev); 103 104 spin_lock_bh(&ax25_dev_lock); 105 106 #ifdef CONFIG_AX25_DAMA_SLAVE 107 ax25_ds_del_timer(ax25_dev); 108 #endif 109 110 /* 111 * Remove any packet forwarding that points to this device. 112 */ 113 for (s = ax25_dev_list; s != NULL; s = s->next) 114 if (s->forward == dev) 115 s->forward = NULL; 116 117 if ((s = ax25_dev_list) == ax25_dev) { 118 ax25_dev_list = s->next; 119 goto unlock_put; 120 } 121 122 while (s != NULL && s->next != NULL) { 123 if (s->next == ax25_dev) { 124 s->next = ax25_dev->next; 125 goto unlock_put; 126 } 127 128 s = s->next; 129 } 130 spin_unlock_bh(&ax25_dev_lock); 131 dev->ax25_ptr = NULL; 132 ax25_dev_put(ax25_dev); 133 return; 134 135 unlock_put: 136 spin_unlock_bh(&ax25_dev_lock); 137 ax25_dev_put(ax25_dev); 138 dev->ax25_ptr = NULL; 139 dev_put_track(dev, &ax25_dev->dev_tracker); 140 ax25_dev_put(ax25_dev); 141 } 142 143 int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd) 144 { 145 ax25_dev *ax25_dev, *fwd_dev; 146 147 if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL) 148 return -EINVAL; 149 150 switch (cmd) { 151 case SIOCAX25ADDFWD: 152 fwd_dev = ax25_addr_ax25dev(&fwd->port_to); 153 if (!fwd_dev) { 154 ax25_dev_put(ax25_dev); 155 return -EINVAL; 156 } 157 if (ax25_dev->forward) { 158 ax25_dev_put(fwd_dev); 159 ax25_dev_put(ax25_dev); 160 return -EINVAL; 161 } 162 ax25_dev->forward = fwd_dev->dev; 163 ax25_dev_put(fwd_dev); 164 ax25_dev_put(ax25_dev); 165 break; 166 167 case SIOCAX25DELFWD: 168 if (!ax25_dev->forward) { 169 ax25_dev_put(ax25_dev); 170 return -EINVAL; 171 } 172 ax25_dev->forward = NULL; 173 ax25_dev_put(ax25_dev); 174 break; 175 176 default: 177 ax25_dev_put(ax25_dev); 178 return -EINVAL; 179 } 180 181 return 0; 182 } 183 184 struct net_device *ax25_fwd_dev(struct net_device *dev) 185 { 186 ax25_dev *ax25_dev; 187 188 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 189 return dev; 190 191 if (ax25_dev->forward == NULL) 192 return dev; 193 194 return ax25_dev->forward; 195 } 196 197 /* 198 * Free all memory associated with device structures. 199 */ 200 void __exit ax25_dev_free(void) 201 { 202 ax25_dev *s, *ax25_dev; 203 204 spin_lock_bh(&ax25_dev_lock); 205 ax25_dev = ax25_dev_list; 206 while (ax25_dev != NULL) { 207 s = ax25_dev; 208 dev_put_track(ax25_dev->dev, &ax25_dev->dev_tracker); 209 ax25_dev = ax25_dev->next; 210 kfree(s); 211 } 212 ax25_dev_list = NULL; 213 spin_unlock_bh(&ax25_dev_lock); 214 } 215