contrib/hostapd-0.4.9/driver_wired.c

   1 /*
   2  * Host AP (software wireless LAN access point) user space daemon for
   3  * Host AP kernel driver / Kernel driver communication
   4  * Copyright (c) 2002-2005, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Copyright (c) 2004, Gunter Burchardt <tira@isx.de>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * Alternatively, this software may be distributed under the terms of BSD
  12  * license.
  13  *
  14  * See README and COPYING for more details.
  15  */
  16
  17 #include <stdlib.h>
  18 #include <stdio.h>
  19 #include <string.h>
  20 #include <unistd.h>
  21 #include <errno.h>
  22 #include <sys/ioctl.h>
  23 #include <netinet/in.h>
  24 #include <signal.h>
  25 #include <sys/types.h>
  26 #include <sys/socket.h>
  27
  28 #ifdef USE_KERNEL_HEADERS
  29 #include <asm/types.h>
  30 #include <linux/if_packet.h>
  31 #include <linux/if_ether.h>   /* The L2 protocols */
  32 #include <linux/if_arp.h>
  33 #include <linux/if.h>
  34 #else /* USE_KERNEL_HEADERS */
  35 #include <net/if_arp.h>
  36 #include <net/if.h>
  37 #include <netpacket/packet.h>
  38 #endif /* USE_KERNEL_HEADERS */
  39
  40 #include "hostapd.h"
  41 #include "ieee802_1x.h"
  42 #include "eloop.h"
  43 #include "sta_info.h"
  44 #include "driver.h"
  45 #include "accounting.h"
  46
  47
  48 struct wired_driver_data {
  49         struct driver_ops ops;
  50         struct hostapd_data *hapd;
  51
  52         int sock; /* raw packet socket for driver access */
  53         int dhcp_sock; /* socket for dhcp packets */
  54         int use_pae_group_addr;
  55 };
  56
  57 static const struct driver_ops wired_driver_ops;
  58
  59
  60 #define WIRED_EAPOL_MULTICAST_GROUP     {0x01,0x80,0xc2,0x00,0x00,0x03}
  61
  62
  63 /* TODO: detecting new devices should eventually be changed from using DHCP
  64  * snooping to trigger on any packet from a new layer 2 MAC address, e.g.,
  65  * based on ebtables, etc. */
  66
  67 struct dhcp_message {
  68         u_int8_t op;
  69         u_int8_t htype;
  70         u_int8_t hlen;
  71         u_int8_t hops;
  72         u_int32_t xid;
  73         u_int16_t secs;
  74         u_int16_t flags;
  75         u_int32_t ciaddr;
  76         u_int32_t yiaddr;
  77         u_int32_t siaddr;
  78         u_int32_t giaddr;
  79         u_int8_t chaddr[16];
  80         u_int8_t sname[64];
  81         u_int8_t file[128];
  82         u_int32_t cookie;
  83         u_int8_t options[308]; /* 312 - cookie */
  84 };
  85
  86
  87 static void wired_possible_new_sta(struct hostapd_data *hapd, u8 *addr)
  88 {
  89         struct sta_info *sta;
  90
  91         sta = ap_get_sta(hapd, addr);
  92         if (sta)
  93                 return;
  94
  95         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Data frame from unknown STA "
  96                       MACSTR " - adding a new STA\n", MAC2STR(addr));
  97         sta = ap_sta_add(hapd, addr);
  98         if (sta) {
  99                 hostapd_new_assoc_sta(hapd, sta, 0);
 100                 accounting_sta_get_id(hapd, sta);
 101         } else {
 102                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL, "Failed to add STA entry "
 103                               "for " MACSTR "\n", MAC2STR(addr));
 104         }
 105 }
 106
 107
 108 static void handle_data(struct hostapd_data *hapd, unsigned char *buf,
 109                         size_t len)
 110 {
 111         struct ieee8023_hdr *hdr;
 112         u8 *pos, *sa;
 113         size_t left;
 114
 115         /* must contain at least ieee8023_hdr 6 byte source, 6 byte dest,
 116          * 2 byte ethertype */
 117         if (len < 14) {
 118                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE, "handle_data: too short "
 119                               "(%lu)\n", (unsigned long) len);
 120                 return;
 121         }
 122
 123         hdr = (struct ieee8023_hdr *) buf;
 124
 125         switch (ntohs(hdr->ethertype)) {
 126                 case ETH_P_PAE:
 127                         HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE,
 128                                       "Received EAPOL packet\n");
 129                         sa = hdr->src;
 130                         wired_possible_new_sta(hapd, sa);
 131
 132                         pos = (u8 *) (hdr + 1);
 133                         left = len - sizeof(*hdr);
 134
 135                         ieee802_1x_receive(hapd, sa, pos, left);
 136                 break;
 137
 138         default:
 139                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 140                               "Unknown ethertype 0x%04x in data frame\n",
 141                               ntohs(hdr->ethertype));
 142                 break;
 143         }
 144 }
 145
 146
 147 static void handle_read(int sock, void *eloop_ctx, void *sock_ctx)
 148 {
 149         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 150         int len;
 151         unsigned char buf[3000];
 152
 153         len = recv(sock, buf, sizeof(buf), 0);
 154         if (len < 0) {
 155                 perror("recv");
 156                 return;
 157         }
 158
 159         handle_data(hapd, buf, len);
 160 }
 161
 162
 163 static void handle_dhcp(int sock, void *eloop_ctx, void *sock_ctx)
 164 {
 165         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 166         int len;
 167         unsigned char buf[3000];
 168         struct dhcp_message *msg;
 169         u8 *mac_address;
 170
 171         len = recv(sock, buf, sizeof(buf), 0);
 172         if (len < 0) {
 173                 perror("recv");
 174                 return;
 175         }
 176
 177         /* must contain at least dhcp_message->chaddr */
 178         if (len < 44) {
 179                 HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE, "handle_dhcp: too short "
 180                               "(%d)\n", len);
 181                 return;
 182         }
 183
 184         msg = (struct dhcp_message *) buf;
 185         mac_address = (u8 *) &(msg->chaddr);
 186
 187         HOSTAPD_DEBUG(HOSTAPD_DEBUG_VERBOSE,
 188                       "Got DHCP broadcast packet from " MACSTR "\n",
 189                       MAC2STR(mac_address));
 190
 191         wired_possible_new_sta(hapd, mac_address);
 192 }
 193
 194
 195 static int wired_init_sockets(struct wired_driver_data *drv)
 196 {
 197         struct hostapd_data *hapd = drv->hapd;
 198         struct ifreq ifr;
 199         struct sockaddr_ll addr;
 200         struct sockaddr_in addr2;
 201         struct packet_mreq mreq;
 202         u8 multicastgroup_eapol[6] = WIRED_EAPOL_MULTICAST_GROUP;
 203         int n = 1;
 204
 205         drv->sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_PAE));
 206         if (drv->sock < 0) {
 207                 perror("socket[PF_PACKET,SOCK_RAW]");
 208                 return -1;
 209         }
 210
 211         if (eloop_register_read_sock(drv->sock, handle_read, hapd, NULL)) {
 212                 printf("Could not register read socket\n");
 213                 return -1;
 214         }
 215
 216         memset(&ifr, 0, sizeof(ifr));
 217         snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s",
 218         hapd->conf->iface);
 219         if (ioctl(drv->sock, SIOCGIFINDEX, &ifr) != 0) {
 220                 perror("ioctl(SIOCGIFINDEX)");
 221                 return -1;
 222         }
 223
 224
 225         memset(&addr, 0, sizeof(addr));
 226         addr.sll_family = AF_PACKET;
 227         addr.sll_ifindex = ifr.ifr_ifindex;
 228         HOSTAPD_DEBUG(HOSTAPD_DEBUG_MINIMAL,
 229                       "Opening raw packet socket for ifindex %d\n",
 230                       addr.sll_ifindex);
 231
 232         if (bind(drv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 233                 perror("bind");
 234                 return -1;
 235         }
 236
 237         /* filter multicast address */
 238         memset(&mreq, 0, sizeof(mreq));
 239         mreq.mr_ifindex = ifr.ifr_ifindex;
 240         mreq.mr_type = PACKET_MR_MULTICAST;
 241         mreq.mr_alen = 6;
 242         memcpy(mreq.mr_address, multicastgroup_eapol, mreq.mr_alen);
 243
 244         if (setsockopt(drv->sock, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq,
 245                        sizeof(mreq)) < 0) {
 246                 perror("setsockopt[SOL_SOCKET,PACKET_ADD_MEMBERSHIP]");
 247                 return -1;
 248         }
 249
 250         memset(&ifr, 0, sizeof(ifr));
 251         snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", hapd->conf->iface);
 252         if (ioctl(drv->sock, SIOCGIFHWADDR, &ifr) != 0) {
 253                 perror("ioctl(SIOCGIFHWADDR)");
 254                 return -1;
 255         }
 256
 257         if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
 258                 printf("Invalid HW-addr family 0x%04x\n",
 259                        ifr.ifr_hwaddr.sa_family);
 260                 return -1;
 261         }
 262         memcpy(hapd->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 263
 264         /* setup dhcp listen socket for sta detection */
 265         if ((drv->dhcp_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
 266                 perror("socket call failed for dhcp");
 267                 return -1;
 268         }
 269
 270         if (eloop_register_read_sock(drv->dhcp_sock, handle_dhcp, hapd, NULL))
 271         {
 272                 printf("Could not register read socket\n");
 273                 return -1;
 274         }
 275
 276         memset(&addr2, 0, sizeof(addr2));
 277         addr2.sin_family = AF_INET;
 278         addr2.sin_port = htons(67);
 279         addr2.sin_addr.s_addr = INADDR_ANY;
 280
 281         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_REUSEADDR, (char *) &n,
 282                        sizeof(n)) == -1) {
 283                 perror("setsockopt[SOL_SOCKET,SO_REUSEADDR]");
 284                 return -1;
 285         }
 286         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BROADCAST, (char *) &n,
 287                        sizeof(n)) == -1) {
 288                 perror("setsockopt[SOL_SOCKET,SO_BROADCAST]");
 289                 return -1;
 290         }
 291
 292         memset(&ifr, 0, sizeof(ifr));
 293         strncpy(ifr.ifr_ifrn.ifrn_name, hapd->conf->iface, IFNAMSIZ);
 294         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BINDTODEVICE,
 295                        (char *) &ifr, sizeof(ifr)) < 0) {
 296                 perror("setsockopt[SOL_SOCKET,SO_BINDTODEVICE]");
 297                 return -1;
 298         }
 299
 300         if (bind(drv->dhcp_sock, (struct sockaddr *) &addr2,
 301                  sizeof(struct sockaddr)) == -1) {
 302                 perror("bind");
 303                 return -1;
 304         }
 305
 306         return 0;
 307 }
 308
 309
 310 static int wired_send_eapol(void *priv, u8 *addr,
 311                             u8 *data, size_t data_len, int encrypt)
 312 {
 313         struct wired_driver_data *drv = priv;
 314         u8 pae_group_addr[ETH_ALEN] = WIRED_EAPOL_MULTICAST_GROUP;
 315         struct ieee8023_hdr *hdr;
 316         size_t len;
 317         u8 *pos;
 318         int res;
 319
 320         len = sizeof(*hdr) + data_len;
 321         hdr = malloc(len);
 322         if (hdr == NULL) {
 323                 printf("malloc() failed for wired_send_eapol(len=%lu)\n",
 324                        (unsigned long) len);
 325                 return -1;
 326         }
 327
 328         memset(hdr, 0, len);
 329         memcpy(hdr->dest, drv->use_pae_group_addr ? pae_group_addr : addr,
 330                ETH_ALEN);
 331         memcpy(hdr->src, drv->hapd->own_addr, ETH_ALEN);
 332         hdr->ethertype = htons(ETH_P_PAE);
 333
 334         pos = (u8 *) (hdr + 1);
 335         memcpy(pos, data, data_len);
 336
 337         res = send(drv->sock, (u8 *) hdr, len, 0);
 338         free(hdr);
 339
 340         if (res < 0) {
 341                 perror("wired_send_eapol: send");
 342                 printf("wired_send_eapol - packet len: %lu - failed\n",
 343                        (unsigned long) len);
 344         }
 345
 346         return res;
 347 }
 348
 349
 350 static int wired_driver_init(struct hostapd_data *hapd)
 351 {
 352         struct wired_driver_data *drv;
 353
 354         drv = malloc(sizeof(struct wired_driver_data));
 355         if (drv == NULL) {
 356                 printf("Could not allocate memory for wired driver data\n");
 357                 return -1;
 358         }
 359
 360         memset(drv, 0, sizeof(*drv));
 361         drv->ops = wired_driver_ops;
 362         drv->hapd = hapd;
 363         drv->use_pae_group_addr = hapd->conf->use_pae_group_addr;
 364
 365         if (wired_init_sockets(drv))
 366                 return -1;
 367
 368         hapd->driver = &drv->ops;
 369         return 0;
 370 }
 371
 372
 373 static void wired_driver_deinit(void *priv)
 374 {
 375         struct wired_driver_data *drv = priv;
 376
 377         drv->hapd->driver = NULL;
 378
 379         if (drv->sock >= 0)
 380                 close(drv->sock);
 381
 382         if (drv->dhcp_sock >= 0)
 383                 close(drv->dhcp_sock);
 384
 385         free(drv);
 386 }
 387
 388
 389 static const struct driver_ops wired_driver_ops = {
 390         .name = "wired",
 391         .init = wired_driver_init,
 392         .deinit = wired_driver_deinit,
 393         .send_eapol = wired_send_eapol,
 394 };
 395
 396 void wired_driver_register(void)
 397 {
 398         driver_register(wired_driver_ops.name, &wired_driver_ops);
 399 }