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