Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Generic HDLC support routines for Linux |
| 3 | * Cisco HDLC support |
| 4 | * |
| 5 | * Copyright (C) 2000 - 2003 Krzysztof Halasa <khc@pm.waw.pl> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms of version 2 of the GNU General Public License |
| 9 | * as published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/poll.h> |
| 16 | #include <linux/errno.h> |
| 17 | #include <linux/if_arp.h> |
| 18 | #include <linux/init.h> |
| 19 | #include <linux/skbuff.h> |
| 20 | #include <linux/pkt_sched.h> |
| 21 | #include <linux/inetdevice.h> |
| 22 | #include <linux/lapb.h> |
| 23 | #include <linux/rtnetlink.h> |
| 24 | #include <linux/hdlc.h> |
| 25 | |
| 26 | #undef DEBUG_HARD_HEADER |
| 27 | |
| 28 | #define CISCO_MULTICAST 0x8F /* Cisco multicast address */ |
| 29 | #define CISCO_UNICAST 0x0F /* Cisco unicast address */ |
| 30 | #define CISCO_KEEPALIVE 0x8035 /* Cisco keepalive protocol */ |
| 31 | #define CISCO_SYS_INFO 0x2000 /* Cisco interface/system info */ |
| 32 | #define CISCO_ADDR_REQ 0 /* Cisco address request */ |
| 33 | #define CISCO_ADDR_REPLY 1 /* Cisco address reply */ |
| 34 | #define CISCO_KEEPALIVE_REQ 2 /* Cisco keepalive request */ |
| 35 | |
| 36 | |
| 37 | static int cisco_hard_header(struct sk_buff *skb, struct net_device *dev, |
| 38 | u16 type, void *daddr, void *saddr, |
| 39 | unsigned int len) |
| 40 | { |
| 41 | hdlc_header *data; |
| 42 | #ifdef DEBUG_HARD_HEADER |
| 43 | printk(KERN_DEBUG "%s: cisco_hard_header called\n", dev->name); |
| 44 | #endif |
| 45 | |
| 46 | skb_push(skb, sizeof(hdlc_header)); |
| 47 | data = (hdlc_header*)skb->data; |
| 48 | if (type == CISCO_KEEPALIVE) |
| 49 | data->address = CISCO_MULTICAST; |
| 50 | else |
| 51 | data->address = CISCO_UNICAST; |
| 52 | data->control = 0; |
| 53 | data->protocol = htons(type); |
| 54 | |
| 55 | return sizeof(hdlc_header); |
| 56 | } |
| 57 | |
| 58 | |
| 59 | |
| 60 | static void cisco_keepalive_send(struct net_device *dev, u32 type, |
| 61 | u32 par1, u32 par2) |
| 62 | { |
| 63 | struct sk_buff *skb; |
| 64 | cisco_packet *data; |
| 65 | |
| 66 | skb = dev_alloc_skb(sizeof(hdlc_header) + sizeof(cisco_packet)); |
| 67 | if (!skb) { |
| 68 | printk(KERN_WARNING |
| 69 | "%s: Memory squeeze on cisco_keepalive_send()\n", |
| 70 | dev->name); |
| 71 | return; |
| 72 | } |
| 73 | skb_reserve(skb, 4); |
| 74 | cisco_hard_header(skb, dev, CISCO_KEEPALIVE, NULL, NULL, 0); |
| 75 | data = (cisco_packet*)skb->tail; |
| 76 | |
| 77 | data->type = htonl(type); |
| 78 | data->par1 = htonl(par1); |
| 79 | data->par2 = htonl(par2); |
| 80 | data->rel = 0xFFFF; |
| 81 | /* we will need do_div here if 1000 % HZ != 0 */ |
| 82 | data->time = htonl((jiffies - INITIAL_JIFFIES) * (1000 / HZ)); |
| 83 | |
| 84 | skb_put(skb, sizeof(cisco_packet)); |
| 85 | skb->priority = TC_PRIO_CONTROL; |
| 86 | skb->dev = dev; |
| 87 | skb->nh.raw = skb->data; |
| 88 | |
| 89 | dev_queue_xmit(skb); |
| 90 | } |
| 91 | |
| 92 | |
| 93 | |
| 94 | static unsigned short cisco_type_trans(struct sk_buff *skb, |
| 95 | struct net_device *dev) |
| 96 | { |
| 97 | hdlc_header *data = (hdlc_header*)skb->data; |
| 98 | |
| 99 | if (skb->len < sizeof(hdlc_header)) |
| 100 | return __constant_htons(ETH_P_HDLC); |
| 101 | |
| 102 | if (data->address != CISCO_MULTICAST && |
| 103 | data->address != CISCO_UNICAST) |
| 104 | return __constant_htons(ETH_P_HDLC); |
| 105 | |
| 106 | switch(data->protocol) { |
| 107 | case __constant_htons(ETH_P_IP): |
| 108 | case __constant_htons(ETH_P_IPX): |
| 109 | case __constant_htons(ETH_P_IPV6): |
| 110 | skb_pull(skb, sizeof(hdlc_header)); |
| 111 | return data->protocol; |
| 112 | default: |
| 113 | return __constant_htons(ETH_P_HDLC); |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | |
| 118 | static int cisco_rx(struct sk_buff *skb) |
| 119 | { |
| 120 | struct net_device *dev = skb->dev; |
| 121 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 122 | hdlc_header *data = (hdlc_header*)skb->data; |
| 123 | cisco_packet *cisco_data; |
| 124 | struct in_device *in_dev; |
| 125 | u32 addr, mask; |
| 126 | |
| 127 | if (skb->len < sizeof(hdlc_header)) |
| 128 | goto rx_error; |
| 129 | |
| 130 | if (data->address != CISCO_MULTICAST && |
| 131 | data->address != CISCO_UNICAST) |
| 132 | goto rx_error; |
| 133 | |
| 134 | switch(ntohs(data->protocol)) { |
| 135 | case CISCO_SYS_INFO: |
| 136 | /* Packet is not needed, drop it. */ |
| 137 | dev_kfree_skb_any(skb); |
| 138 | return NET_RX_SUCCESS; |
| 139 | |
| 140 | case CISCO_KEEPALIVE: |
| 141 | if (skb->len != sizeof(hdlc_header) + CISCO_PACKET_LEN && |
| 142 | skb->len != sizeof(hdlc_header) + CISCO_BIG_PACKET_LEN) { |
| 143 | printk(KERN_INFO "%s: Invalid length of Cisco " |
| 144 | "control packet (%d bytes)\n", |
| 145 | dev->name, skb->len); |
| 146 | goto rx_error; |
| 147 | } |
| 148 | |
| 149 | cisco_data = (cisco_packet*)(skb->data + sizeof(hdlc_header)); |
| 150 | |
| 151 | switch(ntohl (cisco_data->type)) { |
| 152 | case CISCO_ADDR_REQ: /* Stolen from syncppp.c :-) */ |
| 153 | in_dev = dev->ip_ptr; |
| 154 | addr = 0; |
| 155 | mask = ~0; /* is the mask correct? */ |
| 156 | |
| 157 | if (in_dev != NULL) { |
| 158 | struct in_ifaddr **ifap = &in_dev->ifa_list; |
| 159 | |
| 160 | while (*ifap != NULL) { |
| 161 | if (strcmp(dev->name, |
| 162 | (*ifap)->ifa_label) == 0) { |
| 163 | addr = (*ifap)->ifa_local; |
| 164 | mask = (*ifap)->ifa_mask; |
| 165 | break; |
| 166 | } |
| 167 | ifap = &(*ifap)->ifa_next; |
| 168 | } |
| 169 | |
| 170 | cisco_keepalive_send(dev, CISCO_ADDR_REPLY, |
| 171 | addr, mask); |
| 172 | } |
| 173 | dev_kfree_skb_any(skb); |
| 174 | return NET_RX_SUCCESS; |
| 175 | |
| 176 | case CISCO_ADDR_REPLY: |
| 177 | printk(KERN_INFO "%s: Unexpected Cisco IP address " |
| 178 | "reply\n", dev->name); |
| 179 | goto rx_error; |
| 180 | |
| 181 | case CISCO_KEEPALIVE_REQ: |
| 182 | hdlc->state.cisco.rxseq = ntohl(cisco_data->par1); |
| 183 | if (hdlc->state.cisco.request_sent && |
| 184 | ntohl(cisco_data->par2)==hdlc->state.cisco.txseq) { |
| 185 | hdlc->state.cisco.last_poll = jiffies; |
| 186 | if (!hdlc->state.cisco.up) { |
| 187 | u32 sec, min, hrs, days; |
| 188 | sec = ntohl(cisco_data->time) / 1000; |
| 189 | min = sec / 60; sec -= min * 60; |
| 190 | hrs = min / 60; min -= hrs * 60; |
| 191 | days = hrs / 24; hrs -= days * 24; |
| 192 | printk(KERN_INFO "%s: Link up (peer " |
| 193 | "uptime %ud%uh%um%us)\n", |
| 194 | dev->name, days, hrs, |
| 195 | min, sec); |
| 196 | netif_carrier_on(dev); |
| 197 | hdlc->state.cisco.up = 1; |
| 198 | } |
| 199 | } |
| 200 | |
| 201 | dev_kfree_skb_any(skb); |
| 202 | return NET_RX_SUCCESS; |
| 203 | } /* switch(keepalive type) */ |
| 204 | } /* switch(protocol) */ |
| 205 | |
| 206 | printk(KERN_INFO "%s: Unsupported protocol %x\n", dev->name, |
| 207 | data->protocol); |
| 208 | dev_kfree_skb_any(skb); |
| 209 | return NET_RX_DROP; |
| 210 | |
| 211 | rx_error: |
| 212 | hdlc->stats.rx_errors++; /* Mark error */ |
| 213 | dev_kfree_skb_any(skb); |
| 214 | return NET_RX_DROP; |
| 215 | } |
| 216 | |
| 217 | |
| 218 | |
| 219 | static void cisco_timer(unsigned long arg) |
| 220 | { |
| 221 | struct net_device *dev = (struct net_device *)arg; |
| 222 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 223 | |
| 224 | if (hdlc->state.cisco.up && |
| 225 | time_after(jiffies, hdlc->state.cisco.last_poll + |
| 226 | hdlc->state.cisco.settings.timeout * HZ)) { |
| 227 | hdlc->state.cisco.up = 0; |
| 228 | printk(KERN_INFO "%s: Link down\n", dev->name); |
| 229 | netif_carrier_off(dev); |
| 230 | } |
| 231 | |
| 232 | cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ, |
| 233 | ++hdlc->state.cisco.txseq, |
| 234 | hdlc->state.cisco.rxseq); |
| 235 | hdlc->state.cisco.request_sent = 1; |
| 236 | hdlc->state.cisco.timer.expires = jiffies + |
| 237 | hdlc->state.cisco.settings.interval * HZ; |
| 238 | hdlc->state.cisco.timer.function = cisco_timer; |
| 239 | hdlc->state.cisco.timer.data = arg; |
| 240 | add_timer(&hdlc->state.cisco.timer); |
| 241 | } |
| 242 | |
| 243 | |
| 244 | |
| 245 | static void cisco_start(struct net_device *dev) |
| 246 | { |
| 247 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 248 | hdlc->state.cisco.up = 0; |
| 249 | hdlc->state.cisco.request_sent = 0; |
| 250 | hdlc->state.cisco.txseq = hdlc->state.cisco.rxseq = 0; |
| 251 | |
| 252 | init_timer(&hdlc->state.cisco.timer); |
| 253 | hdlc->state.cisco.timer.expires = jiffies + HZ; /*First poll after 1s*/ |
| 254 | hdlc->state.cisco.timer.function = cisco_timer; |
| 255 | hdlc->state.cisco.timer.data = (unsigned long)dev; |
| 256 | add_timer(&hdlc->state.cisco.timer); |
| 257 | } |
| 258 | |
| 259 | |
| 260 | |
| 261 | static void cisco_stop(struct net_device *dev) |
| 262 | { |
| 263 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 264 | del_timer_sync(&hdlc->state.cisco.timer); |
| 265 | if (netif_carrier_ok(dev)) |
| 266 | netif_carrier_off(dev); |
| 267 | hdlc->state.cisco.up = 0; |
| 268 | hdlc->state.cisco.request_sent = 0; |
| 269 | } |
| 270 | |
| 271 | |
| 272 | |
| 273 | int hdlc_cisco_ioctl(struct net_device *dev, struct ifreq *ifr) |
| 274 | { |
| 275 | cisco_proto __user *cisco_s = ifr->ifr_settings.ifs_ifsu.cisco; |
| 276 | const size_t size = sizeof(cisco_proto); |
| 277 | cisco_proto new_settings; |
| 278 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 279 | int result; |
| 280 | |
| 281 | switch (ifr->ifr_settings.type) { |
| 282 | case IF_GET_PROTO: |
| 283 | ifr->ifr_settings.type = IF_PROTO_CISCO; |
| 284 | if (ifr->ifr_settings.size < size) { |
| 285 | ifr->ifr_settings.size = size; /* data size wanted */ |
| 286 | return -ENOBUFS; |
| 287 | } |
| 288 | if (copy_to_user(cisco_s, &hdlc->state.cisco.settings, size)) |
| 289 | return -EFAULT; |
| 290 | return 0; |
| 291 | |
| 292 | case IF_PROTO_CISCO: |
| 293 | if(!capable(CAP_NET_ADMIN)) |
| 294 | return -EPERM; |
| 295 | |
| 296 | if(dev->flags & IFF_UP) |
| 297 | return -EBUSY; |
| 298 | |
| 299 | if (copy_from_user(&new_settings, cisco_s, size)) |
| 300 | return -EFAULT; |
| 301 | |
| 302 | if (new_settings.interval < 1 || |
| 303 | new_settings.timeout < 2) |
| 304 | return -EINVAL; |
| 305 | |
| 306 | result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT); |
| 307 | |
| 308 | if (result) |
| 309 | return result; |
| 310 | |
| 311 | hdlc_proto_detach(hdlc); |
| 312 | memcpy(&hdlc->state.cisco.settings, &new_settings, size); |
| 313 | memset(&hdlc->proto, 0, sizeof(hdlc->proto)); |
| 314 | |
| 315 | hdlc->proto.start = cisco_start; |
| 316 | hdlc->proto.stop = cisco_stop; |
| 317 | hdlc->proto.netif_rx = cisco_rx; |
| 318 | hdlc->proto.type_trans = cisco_type_trans; |
| 319 | hdlc->proto.id = IF_PROTO_CISCO; |
| 320 | dev->hard_start_xmit = hdlc->xmit; |
| 321 | dev->hard_header = cisco_hard_header; |
| 322 | dev->hard_header_cache = NULL; |
| 323 | dev->type = ARPHRD_CISCO; |
| 324 | dev->flags = IFF_POINTOPOINT | IFF_NOARP; |
| 325 | dev->addr_len = 0; |
| 326 | return 0; |
| 327 | } |
| 328 | |
| 329 | return -EINVAL; |
| 330 | } |