dist/wpa/hostapd/driver_wired.c

   1 /*
   2  * hostapd / Kernel driver communication for wired (Ethernet) drivers
   3  * Copyright (c) 2002-2007, Jouni Malinen <j@w1.fi>
   4  * Copyright (c) 2004, Gunter Burchardt <tira@isx.de>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Alternatively, this software may be distributed under the terms of BSD
  11  * license.
  12  *
  13  * See README and COPYING for more details.
  14  */
  15
  16 #include "includes.h"
  17 #include <sys/ioctl.h>
  18
  19 #ifdef USE_KERNEL_HEADERS
  20 #include <asm/types.h>
  21 #include <linux/if_packet.h>
  22 #include <linux/if_ether.h>   /* The L2 protocols */
  23 #include <linux/if_arp.h>
  24 #include <linux/if.h>
  25 #else /* USE_KERNEL_HEADERS */
  26 #include <net/if_arp.h>
  27 #include <net/if.h>
  28 #include <netpacket/packet.h>
  29 #endif /* USE_KERNEL_HEADERS */
  30
  31 #include "hostapd.h"
  32 #include "ieee802_1x.h"
  33 #include "eloop.h"
  34 #include "sta_info.h"
  35 #include "driver.h"
  36 #include "accounting.h"
  37
  38
  39 struct wired_driver_data {
  40         struct hostapd_data *hapd;
  41
  42         int sock; /* raw packet socket for driver access */
  43         int dhcp_sock; /* socket for dhcp packets */
  44         int use_pae_group_addr;
  45 };
  46
  47
  48 #define WIRED_EAPOL_MULTICAST_GROUP     {0x01,0x80,0xc2,0x00,0x00,0x03}
  49
  50
  51 /* TODO: detecting new devices should eventually be changed from using DHCP
  52  * snooping to trigger on any packet from a new layer 2 MAC address, e.g.,
  53  * based on ebtables, etc. */
  54
  55 struct dhcp_message {
  56         u_int8_t op;
  57         u_int8_t htype;
  58         u_int8_t hlen;
  59         u_int8_t hops;
  60         u_int32_t xid;
  61         u_int16_t secs;
  62         u_int16_t flags;
  63         u_int32_t ciaddr;
  64         u_int32_t yiaddr;
  65         u_int32_t siaddr;
  66         u_int32_t giaddr;
  67         u_int8_t chaddr[16];
  68         u_int8_t sname[64];
  69         u_int8_t file[128];
  70         u_int32_t cookie;
  71         u_int8_t options[308]; /* 312 - cookie */
  72 };
  73
  74
  75 static void wired_possible_new_sta(struct hostapd_data *hapd, u8 *addr)
  76 {
  77         struct sta_info *sta;
  78
  79         sta = ap_get_sta(hapd, addr);
  80         if (sta)
  81                 return;
  82
  83         wpa_printf(MSG_DEBUG, "Data frame from unknown STA " MACSTR
  84                    " - adding a new STA", MAC2STR(addr));
  85         sta = ap_sta_add(hapd, addr);
  86         if (sta) {
  87                 hostapd_new_assoc_sta(hapd, sta, 0);
  88                 accounting_sta_get_id(hapd, sta);
  89         } else {
  90                 wpa_printf(MSG_DEBUG, "Failed to add STA entry for " MACSTR,
  91                            MAC2STR(addr));
  92         }
  93 }
  94
  95
  96 static void handle_data(struct hostapd_data *hapd, unsigned char *buf,
  97                         size_t len)
  98 {
  99         struct ieee8023_hdr *hdr;
 100         u8 *pos, *sa;
 101         size_t left;
 102
 103         /* must contain at least ieee8023_hdr 6 byte source, 6 byte dest,
 104          * 2 byte ethertype */
 105         if (len < 14) {
 106                 wpa_printf(MSG_MSGDUMP, "handle_data: too short (%lu)",
 107                            (unsigned long) len);
 108                 return;
 109         }
 110
 111         hdr = (struct ieee8023_hdr *) buf;
 112
 113         switch (ntohs(hdr->ethertype)) {
 114                 case ETH_P_PAE:
 115                         wpa_printf(MSG_MSGDUMP, "Received EAPOL packet");
 116                         sa = hdr->src;
 117                         wired_possible_new_sta(hapd, sa);
 118
 119                         pos = (u8 *) (hdr + 1);
 120                         left = len - sizeof(*hdr);
 121
 122                         ieee802_1x_receive(hapd, sa, pos, left);
 123                 break;
 124
 125         default:
 126                 wpa_printf(MSG_DEBUG, "Unknown ethertype 0x%04x in data frame",
 127                            ntohs(hdr->ethertype));
 128                 break;
 129         }
 130 }
 131
 132
 133 static void handle_read(int sock, void *eloop_ctx, void *sock_ctx)
 134 {
 135         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 136         int len;
 137         unsigned char buf[3000];
 138
 139         len = recv(sock, buf, sizeof(buf), 0);
 140         if (len < 0) {
 141                 perror("recv");
 142                 return;
 143         }
 144
 145         handle_data(hapd, buf, len);
 146 }
 147
 148
 149 static void handle_dhcp(int sock, void *eloop_ctx, void *sock_ctx)
 150 {
 151         struct hostapd_data *hapd = (struct hostapd_data *) eloop_ctx;
 152         int len;
 153         unsigned char buf[3000];
 154         struct dhcp_message *msg;
 155         u8 *mac_address;
 156
 157         len = recv(sock, buf, sizeof(buf), 0);
 158         if (len < 0) {
 159                 perror("recv");
 160                 return;
 161         }
 162
 163         /* must contain at least dhcp_message->chaddr */
 164         if (len < 44) {
 165                 wpa_printf(MSG_MSGDUMP, "handle_dhcp: too short (%d)", len);
 166                 return;
 167         }
 168
 169         msg = (struct dhcp_message *) buf;
 170         mac_address = (u8 *) &(msg->chaddr);
 171
 172         wpa_printf(MSG_MSGDUMP, "Got DHCP broadcast packet from " MACSTR,
 173                    MAC2STR(mac_address));
 174
 175         wired_possible_new_sta(hapd, mac_address);
 176 }
 177
 178
 179 static int wired_init_sockets(struct wired_driver_data *drv)
 180 {
 181         struct hostapd_data *hapd = drv->hapd;
 182         struct ifreq ifr;
 183         struct sockaddr_ll addr;
 184         struct sockaddr_in addr2;
 185         struct packet_mreq mreq;
 186         u8 multicastgroup_eapol[6] = WIRED_EAPOL_MULTICAST_GROUP;
 187         int n = 1;
 188
 189         drv->sock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_PAE));
 190         if (drv->sock < 0) {
 191                 perror("socket[PF_PACKET,SOCK_RAW]");
 192                 return -1;
 193         }
 194
 195         if (eloop_register_read_sock(drv->sock, handle_read, hapd, NULL)) {
 196                 printf("Could not register read socket\n");
 197                 return -1;
 198         }
 199
 200         memset(&ifr, 0, sizeof(ifr));
 201         os_strlcpy(ifr.ifr_name, hapd->conf->iface, sizeof(ifr.ifr_name));
 202         if (ioctl(drv->sock, SIOCGIFINDEX, &ifr) != 0) {
 203                 perror("ioctl(SIOCGIFINDEX)");
 204                 return -1;
 205         }
 206
 207
 208         memset(&addr, 0, sizeof(addr));
 209         addr.sll_family = AF_PACKET;
 210         addr.sll_ifindex = ifr.ifr_ifindex;
 211         wpa_printf(MSG_DEBUG, "Opening raw packet socket for ifindex %d",
 212                    addr.sll_ifindex);
 213
 214         if (bind(drv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 215                 perror("bind");
 216                 return -1;
 217         }
 218
 219         /* filter multicast address */
 220         memset(&mreq, 0, sizeof(mreq));
 221         mreq.mr_ifindex = ifr.ifr_ifindex;
 222         mreq.mr_type = PACKET_MR_MULTICAST;
 223         mreq.mr_alen = 6;
 224         memcpy(mreq.mr_address, multicastgroup_eapol, mreq.mr_alen);
 225
 226         if (setsockopt(drv->sock, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq,
 227                        sizeof(mreq)) < 0) {
 228                 perror("setsockopt[SOL_SOCKET,PACKET_ADD_MEMBERSHIP]");
 229                 return -1;
 230         }
 231
 232         memset(&ifr, 0, sizeof(ifr));
 233         os_strlcpy(ifr.ifr_name, hapd->conf->iface, sizeof(ifr.ifr_name));
 234         if (ioctl(drv->sock, SIOCGIFHWADDR, &ifr) != 0) {
 235                 perror("ioctl(SIOCGIFHWADDR)");
 236                 return -1;
 237         }
 238
 239         if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
 240                 printf("Invalid HW-addr family 0x%04x\n",
 241                        ifr.ifr_hwaddr.sa_family);
 242                 return -1;
 243         }
 244         memcpy(hapd->own_addr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 245
 246         /* setup dhcp listen socket for sta detection */
 247         if ((drv->dhcp_sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
 248                 perror("socket call failed for dhcp");
 249                 return -1;
 250         }
 251
 252         if (eloop_register_read_sock(drv->dhcp_sock, handle_dhcp, hapd, NULL))
 253         {
 254                 printf("Could not register read socket\n");
 255                 return -1;
 256         }
 257
 258         memset(&addr2, 0, sizeof(addr2));
 259         addr2.sin_family = AF_INET;
 260         addr2.sin_port = htons(67);
 261         addr2.sin_addr.s_addr = INADDR_ANY;
 262
 263         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_REUSEADDR, (char *) &n,
 264                        sizeof(n)) == -1) {
 265                 perror("setsockopt[SOL_SOCKET,SO_REUSEADDR]");
 266                 return -1;
 267         }
 268         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BROADCAST, (char *) &n,
 269                        sizeof(n)) == -1) {
 270                 perror("setsockopt[SOL_SOCKET,SO_BROADCAST]");
 271                 return -1;
 272         }
 273
 274         memset(&ifr, 0, sizeof(ifr));
 275         os_strlcpy(ifr.ifr_ifrn.ifrn_name, hapd->conf->iface, IFNAMSIZ);
 276         if (setsockopt(drv->dhcp_sock, SOL_SOCKET, SO_BINDTODEVICE,
 277                        (char *) &ifr, sizeof(ifr)) < 0) {
 278                 perror("setsockopt[SOL_SOCKET,SO_BINDTODEVICE]");
 279                 return -1;
 280         }
 281
 282         if (bind(drv->dhcp_sock, (struct sockaddr *) &addr2,
 283                  sizeof(struct sockaddr)) == -1) {
 284                 perror("bind");
 285                 return -1;
 286         }
 287
 288         return 0;
 289 }
 290
 291
 292 static int wired_send_eapol(void *priv, const u8 *addr,
 293                             const u8 *data, size_t data_len, int encrypt,
 294                             const u8 *own_addr)
 295 {
 296         struct wired_driver_data *drv = priv;
 297         u8 pae_group_addr[ETH_ALEN] = WIRED_EAPOL_MULTICAST_GROUP;
 298         struct ieee8023_hdr *hdr;
 299         size_t len;
 300         u8 *pos;
 301         int res;
 302
 303         len = sizeof(*hdr) + data_len;
 304         hdr = os_zalloc(len);
 305         if (hdr == NULL) {
 306                 printf("malloc() failed for wired_send_eapol(len=%lu)\n",
 307                        (unsigned long) len);
 308                 return -1;
 309         }
 310
 311         memcpy(hdr->dest, drv->use_pae_group_addr ? pae_group_addr : addr,
 312                ETH_ALEN);
 313         memcpy(hdr->src, own_addr, ETH_ALEN);
 314         hdr->ethertype = htons(ETH_P_PAE);
 315
 316         pos = (u8 *) (hdr + 1);
 317         memcpy(pos, data, data_len);
 318
 319         res = send(drv->sock, (u8 *) hdr, len, 0);
 320         free(hdr);
 321
 322         if (res < 0) {
 323                 perror("wired_send_eapol: send");
 324                 printf("wired_send_eapol - packet len: %lu - failed\n",
 325                        (unsigned long) len);
 326         }
 327
 328         return res;
 329 }
 330
 331
 332 static void * wired_driver_init(struct hostapd_data *hapd)
 333 {
 334         struct wired_driver_data *drv;
 335
 336         drv = os_zalloc(sizeof(struct wired_driver_data));
 337         if (drv == NULL) {
 338                 printf("Could not allocate memory for wired driver data\n");
 339                 return NULL;
 340         }
 341
 342         drv->hapd = hapd;
 343         drv->use_pae_group_addr = hapd->conf->use_pae_group_addr;
 344
 345         if (wired_init_sockets(drv)) {
 346                 free(drv);
 347                 return NULL;
 348         }
 349
 350         return drv;
 351 }
 352
 353
 354 static void wired_driver_deinit(void *priv)
 355 {
 356         struct wired_driver_data *drv = priv;
 357
 358         if (drv->sock >= 0)
 359                 close(drv->sock);
 360
 361         if (drv->dhcp_sock >= 0)
 362                 close(drv->dhcp_sock);
 363
 364         free(drv);
 365 }
 366
 367
 368 const struct wpa_driver_ops wpa_driver_wired_ops = {
 369         .name = "wired",
 370         .init = wired_driver_init,
 371         .deinit = wired_driver_deinit,
 372         .send_eapol = wired_send_eapol,
 373 };