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 ax25_dev = kzalloc(sizeof(*ax25_dev), GFP_KERNEL); 56 if (!ax25_dev) { 57 printk(KERN_ERR "AX.25: ax25_dev_device_up - out of memory\n"); 58 return; 59 } 60 61 refcount_set(&ax25_dev->refcount, 1); 62 dev->ax25_ptr = ax25_dev; 63 ax25_dev->dev = dev; 64 netdev_hold(dev, &ax25_dev->dev_tracker, GFP_KERNEL); 65 ax25_dev->forward = NULL; 66 ax25_dev->device_up = true; 67 68 ax25_dev->values[AX25_VALUES_IPDEFMODE] = AX25_DEF_IPDEFMODE; 69 ax25_dev->values[AX25_VALUES_AXDEFMODE] = AX25_DEF_AXDEFMODE; 70 ax25_dev->values[AX25_VALUES_BACKOFF] = AX25_DEF_BACKOFF; 71 ax25_dev->values[AX25_VALUES_CONMODE] = AX25_DEF_CONMODE; 72 ax25_dev->values[AX25_VALUES_WINDOW] = AX25_DEF_WINDOW; 73 ax25_dev->values[AX25_VALUES_EWINDOW] = AX25_DEF_EWINDOW; 74 ax25_dev->values[AX25_VALUES_T1] = AX25_DEF_T1; 75 ax25_dev->values[AX25_VALUES_T2] = AX25_DEF_T2; 76 ax25_dev->values[AX25_VALUES_T3] = AX25_DEF_T3; 77 ax25_dev->values[AX25_VALUES_IDLE] = AX25_DEF_IDLE; 78 ax25_dev->values[AX25_VALUES_N2] = AX25_DEF_N2; 79 ax25_dev->values[AX25_VALUES_PACLEN] = AX25_DEF_PACLEN; 80 ax25_dev->values[AX25_VALUES_PROTOCOL] = AX25_DEF_PROTOCOL; 81 ax25_dev->values[AX25_VALUES_DS_TIMEOUT]= AX25_DEF_DS_TIMEOUT; 82 83 #if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER) 84 ax25_ds_setup_timer(ax25_dev); 85 #endif 86 87 spin_lock_bh(&ax25_dev_lock); 88 ax25_dev->next = ax25_dev_list; 89 ax25_dev_list = ax25_dev; 90 spin_unlock_bh(&ax25_dev_lock); 91 ax25_dev_hold(ax25_dev); 92 93 ax25_register_dev_sysctl(ax25_dev); 94 } 95 96 void ax25_dev_device_down(struct net_device *dev) 97 { 98 ax25_dev *s, *ax25_dev; 99 100 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 101 return; 102 103 ax25_unregister_dev_sysctl(ax25_dev); 104 105 spin_lock_bh(&ax25_dev_lock); 106 107 #ifdef CONFIG_AX25_DAMA_SLAVE 108 ax25_ds_del_timer(ax25_dev); 109 #endif 110 111 /* 112 * Remove any packet forwarding that points to this device. 113 */ 114 for (s = ax25_dev_list; s != NULL; s = s->next) 115 if (s->forward == dev) 116 s->forward = NULL; 117 118 if ((s = ax25_dev_list) == ax25_dev) { 119 ax25_dev_list = s->next; 120 goto unlock_put; 121 } 122 123 while (s != NULL && s->next != NULL) { 124 if (s->next == ax25_dev) { 125 s->next = ax25_dev->next; 126 goto unlock_put; 127 } 128 129 s = s->next; 130 } 131 spin_unlock_bh(&ax25_dev_lock); 132 dev->ax25_ptr = NULL; 133 ax25_dev_put(ax25_dev); 134 return; 135 136 unlock_put: 137 spin_unlock_bh(&ax25_dev_lock); 138 ax25_dev_put(ax25_dev); 139 dev->ax25_ptr = NULL; 140 netdev_put(dev, &ax25_dev->dev_tracker); 141 ax25_dev_put(ax25_dev); 142 } 143 144 int ax25_fwd_ioctl(unsigned int cmd, struct ax25_fwd_struct *fwd) 145 { 146 ax25_dev *ax25_dev, *fwd_dev; 147 148 if ((ax25_dev = ax25_addr_ax25dev(&fwd->port_from)) == NULL) 149 return -EINVAL; 150 151 switch (cmd) { 152 case SIOCAX25ADDFWD: 153 fwd_dev = ax25_addr_ax25dev(&fwd->port_to); 154 if (!fwd_dev) { 155 ax25_dev_put(ax25_dev); 156 return -EINVAL; 157 } 158 if (ax25_dev->forward) { 159 ax25_dev_put(fwd_dev); 160 ax25_dev_put(ax25_dev); 161 return -EINVAL; 162 } 163 ax25_dev->forward = fwd_dev->dev; 164 ax25_dev_put(fwd_dev); 165 ax25_dev_put(ax25_dev); 166 break; 167 168 case SIOCAX25DELFWD: 169 if (!ax25_dev->forward) { 170 ax25_dev_put(ax25_dev); 171 return -EINVAL; 172 } 173 ax25_dev->forward = NULL; 174 ax25_dev_put(ax25_dev); 175 break; 176 177 default: 178 ax25_dev_put(ax25_dev); 179 return -EINVAL; 180 } 181 182 return 0; 183 } 184 185 struct net_device *ax25_fwd_dev(struct net_device *dev) 186 { 187 ax25_dev *ax25_dev; 188 189 if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) 190 return dev; 191 192 if (ax25_dev->forward == NULL) 193 return dev; 194 195 return ax25_dev->forward; 196 } 197 198 /* 199 * Free all memory associated with device structures. 200 */ 201 void __exit ax25_dev_free(void) 202 { 203 ax25_dev *s, *ax25_dev; 204 205 spin_lock_bh(&ax25_dev_lock); 206 ax25_dev = ax25_dev_list; 207 while (ax25_dev != NULL) { 208 s = ax25_dev; 209 netdev_put(ax25_dev->dev, &ax25_dev->dev_tracker); 210 ax25_dev = ax25_dev->next; 211 kfree(s); 212 } 213 ax25_dev_list = NULL; 214 spin_unlock_bh(&ax25_dev_lock); 215 } 216