wlantest/rx_data.c

   1 /*
   2  * Received Data frame processing
   3  * Copyright (c) 2010, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "utils/includes.h"
  16 #include <linux/if_ether.h>
  17
  18 #include "utils/common.h"
  19 #include "common/defs.h"
  20 #include "common/ieee802_11_defs.h"
  21 #include "wlantest.h"
  22
  23
  24 static const char * data_stype(u16 stype)
  25 {
  26         switch (stype) {
  27         case WLAN_FC_STYPE_DATA:
  28                 return "DATA";
  29         case WLAN_FC_STYPE_DATA_CFACK:
  30                 return "DATA-CFACK";
  31         case WLAN_FC_STYPE_DATA_CFPOLL:
  32                 return "DATA-CFPOLL";
  33         case WLAN_FC_STYPE_DATA_CFACKPOLL:
  34                 return "DATA-CFACKPOLL";
  35         case WLAN_FC_STYPE_NULLFUNC:
  36                 return "NULLFUNC";
  37         case WLAN_FC_STYPE_CFACK:
  38                 return "CFACK";
  39         case WLAN_FC_STYPE_CFPOLL:
  40                 return "CFPOLL";
  41         case WLAN_FC_STYPE_CFACKPOLL:
  42                 return "CFACKPOLL";
  43         case WLAN_FC_STYPE_QOS_DATA:
  44                 return "QOSDATA";
  45         case WLAN_FC_STYPE_QOS_DATA_CFACK:
  46                 return "QOSDATA-CFACK";
  47         case WLAN_FC_STYPE_QOS_DATA_CFPOLL:
  48                 return "QOSDATA-CFPOLL";
  49         case WLAN_FC_STYPE_QOS_DATA_CFACKPOLL:
  50                 return "QOSDATA-CFACKPOLL";
  51         case WLAN_FC_STYPE_QOS_NULL:
  52                 return "QOS-NULL";
  53         case WLAN_FC_STYPE_QOS_CFPOLL:
  54                 return "QOS-CFPOLL";
  55         case WLAN_FC_STYPE_QOS_CFACKPOLL:
  56                 return "QOS-CFACKPOLL";
  57         }
  58         return "??";
  59 }
  60
  61
  62 static void rx_data_eth(struct wlantest *wt, const u8 *bssid,
  63                         const u8 *sta_addr, const u8 *dst, const u8 *src,
  64                         u16 ethertype, const u8 *data, size_t len, int prot)
  65 {
  66         switch (ethertype) {
  67         case ETH_P_PAE:
  68                 rx_data_eapol(wt, dst, src, data, len, prot);
  69                 break;
  70         case ETH_P_IP:
  71                 rx_data_ip(wt, bssid, sta_addr, dst, src, data, len);
  72                 break;
  73         case 0x890d:
  74                 rx_data_80211_encap(wt, bssid, sta_addr, dst, src, data, len);
  75                 break;
  76         }
  77 }
  78
  79
  80 static void rx_data_process(struct wlantest *wt, const u8 *bssid,
  81                             const u8 *sta_addr,
  82                             const u8 *dst, const u8 *src,
  83                             const u8 *data, size_t len, int prot)
  84 {
  85         if (len == 0)
  86                 return;
  87
  88         if (len >= 8 && os_memcmp(data, "\xaa\xaa\x03\x00\x00\x00", 6) == 0) {
  89                 rx_data_eth(wt, bssid, sta_addr, dst, src,
  90                             WPA_GET_BE16(data + 6), data + 8, len - 8, prot);
  91                 return;
  92         }
  93
  94         wpa_hexdump(MSG_DEBUG, "Unrecognized LLC", data, len > 8 ? 8 : len);
  95 }
  96
  97
  98 static void rx_data_bss_prot_group(struct wlantest *wt,
  99                                    const struct ieee80211_hdr *hdr,
 100                                    const u8 *qos, const u8 *dst, const u8 *src,
 101                                    const u8 *data, size_t len)
 102 {
 103         struct wlantest_bss *bss;
 104         int keyid;
 105         u8 *decrypted;
 106         size_t dlen;
 107         u8 pn[6];
 108
 109         bss = bss_get(wt, hdr->addr2);
 110         if (bss == NULL)
 111                 return;
 112         if (len < 4) {
 113                 wpa_printf(MSG_INFO, "Too short group addressed data frame");
 114                 return;
 115         }
 116
 117         if (bss->group_cipher & (WPA_CIPHER_TKIP | WPA_CIPHER_CCMP) &&
 118             !(data[3] & 0x20)) {
 119                     wpa_printf(MSG_INFO, "Expected TKIP/CCMP frame from "
 120                                MACSTR " did not have ExtIV bit set to 1",
 121                                MAC2STR(bss->bssid));
 122                     return;
 123         }
 124
 125         if (bss->group_cipher == WPA_CIPHER_TKIP) {
 126                 if (data[3] & 0x1f) {
 127                         wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
 128                                    "non-zero reserved bit",
 129                                    MAC2STR(bss->bssid));
 130                 }
 131                 if (data[1] != ((data[0] | 0x20) & 0x7f)) {
 132                         wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
 133                                    "incorrect WEPSeed[1] (was 0x%x, expected "
 134                                    "0x%x)",
 135                                    MAC2STR(bss->bssid), data[1],
 136                                    (data[0] | 0x20) & 0x7f);
 137                 }
 138         } else if (bss->group_cipher == WPA_CIPHER_CCMP) {
 139                 if (data[2] != 0 || (data[3] & 0x1f) != 0) {
 140                         wpa_printf(MSG_INFO, "CCMP frame from " MACSTR " used "
 141                                    "non-zero reserved bit",
 142                                    MAC2STR(bss->bssid));
 143                 }
 144         }
 145
 146         keyid = data[3] >> 6;
 147         if (bss->gtk_len[keyid] == 0) {
 148                 wpa_printf(MSG_MSGDUMP, "No GTK known to decrypt the frame "
 149                            "(A2=" MACSTR " KeyID=%d)",
 150                            MAC2STR(hdr->addr2), keyid);
 151                 return;
 152         }
 153
 154         if (bss->group_cipher == WPA_CIPHER_TKIP)
 155                 tkip_get_pn(pn, data);
 156         else
 157                 ccmp_get_pn(pn, data);
 158         if (os_memcmp(pn, bss->rsc[keyid], 6) <= 0) {
 159                 wpa_printf(MSG_INFO, "CCMP/TKIP replay detected: SA=" MACSTR,
 160                            MAC2STR(hdr->addr2));
 161                 wpa_hexdump(MSG_INFO, "RX PN", pn, 6);
 162                 wpa_hexdump(MSG_INFO, "RSC", bss->rsc[keyid], 6);
 163         }
 164
 165         if (bss->group_cipher == WPA_CIPHER_TKIP)
 166                 decrypted = tkip_decrypt(bss->gtk[keyid], hdr, data, len,
 167                                          &dlen);
 168         else
 169                 decrypted = ccmp_decrypt(bss->gtk[keyid], hdr, data, len,
 170                                          &dlen);
 171         if (decrypted) {
 172                 rx_data_process(wt, bss->bssid, NULL, dst, src, decrypted,
 173                                 dlen, 1);
 174                 os_memcpy(bss->rsc[keyid], pn, 6);
 175                 write_pcap_decrypted(wt, (const u8 *) hdr, 24 + (qos ? 2 : 0),
 176                                      decrypted, dlen);
 177         }
 178         os_free(decrypted);
 179 }
 180
 181
 182 static void rx_data_bss_prot(struct wlantest *wt,
 183                              const struct ieee80211_hdr *hdr, const u8 *qos,
 184                              const u8 *dst, const u8 *src, const u8 *data,
 185                              size_t len)
 186 {
 187         struct wlantest_bss *bss;
 188         struct wlantest_sta *sta, *sta2;
 189         int keyid;
 190         u16 fc = le_to_host16(hdr->frame_control);
 191         u8 *decrypted;
 192         size_t dlen;
 193         int tid;
 194         u8 pn[6], *rsc;
 195         struct wlantest_tdls *tdls = NULL;
 196         const u8 *tk = NULL;
 197
 198         if (hdr->addr1[0] & 0x01) {
 199                 rx_data_bss_prot_group(wt, hdr, qos, dst, src, data, len);
 200                 return;
 201         }
 202
 203         if (fc & WLAN_FC_TODS) {
 204                 bss = bss_get(wt, hdr->addr1);
 205                 if (bss == NULL)
 206                         return;
 207                 sta = sta_get(bss, hdr->addr2);
 208         } else if (fc & WLAN_FC_FROMDS) {
 209                 bss = bss_get(wt, hdr->addr2);
 210                 if (bss == NULL)
 211                         return;
 212                 sta = sta_get(bss, hdr->addr1);
 213         } else {
 214                 bss = bss_get(wt, hdr->addr3);
 215                 if (bss == NULL)
 216                         return;
 217                 sta = sta_find(bss, hdr->addr2);
 218                 sta2 = sta_find(bss, hdr->addr1);
 219                 if (sta == NULL || sta2 == NULL)
 220                         return;
 221                 dl_list_for_each(tdls, &bss->tdls, struct wlantest_tdls, list)
 222                 {
 223                         if ((tdls->init == sta && tdls->resp == sta2) ||
 224                             (tdls->init == sta2 && tdls->resp == sta)) {
 225                                 if (!tdls->link_up)
 226                                         wpa_printf(MSG_DEBUG, "TDLS: Link not "
 227                                                    "up, but Data frame seen");
 228                                 tk = tdls->tpk.tk;
 229                                 break;
 230                         }
 231                 }
 232         }
 233         if ((sta == NULL || !sta->ptk_set) && tk == NULL) {
 234                 wpa_printf(MSG_MSGDUMP, "No PTK known to decrypt the frame");
 235                 return;
 236         }
 237
 238         if (len < 4) {
 239                 wpa_printf(MSG_INFO, "Too short encrypted data frame");
 240                 return;
 241         }
 242
 243         if (sta->pairwise_cipher & (WPA_CIPHER_TKIP | WPA_CIPHER_CCMP) &&
 244             !(data[3] & 0x20)) {
 245                     wpa_printf(MSG_INFO, "Expected TKIP/CCMP frame from "
 246                                MACSTR " did not have ExtIV bit set to 1",
 247                                MAC2STR(src));
 248                     return;
 249         }
 250
 251         if (tk == NULL && sta->pairwise_cipher == WPA_CIPHER_TKIP) {
 252                 if (data[3] & 0x1f) {
 253                         wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
 254                                    "non-zero reserved bit",
 255                                    MAC2STR(hdr->addr2));
 256                 }
 257                 if (data[1] != ((data[0] | 0x20) & 0x7f)) {
 258                         wpa_printf(MSG_INFO, "TKIP frame from " MACSTR " used "
 259                                    "incorrect WEPSeed[1] (was 0x%x, expected "
 260                                    "0x%x)",
 261                                    MAC2STR(hdr->addr2), data[1],
 262                                    (data[0] | 0x20) & 0x7f);
 263                 }
 264         } else if (tk || sta->pairwise_cipher == WPA_CIPHER_CCMP) {
 265                 if (data[2] != 0 || (data[3] & 0x1f) != 0) {
 266                         wpa_printf(MSG_INFO, "CCMP frame from " MACSTR " used "
 267                                    "non-zero reserved bit",
 268                                    MAC2STR(hdr->addr2));
 269                 }
 270         }
 271
 272         keyid = data[3] >> 6;
 273         if (keyid != 0) {
 274                 wpa_printf(MSG_INFO, "Unexpected non-zero KeyID %d in "
 275                            "individually addressed Data frame from " MACSTR,
 276                            keyid, MAC2STR(hdr->addr2));
 277         }
 278
 279         if (qos)
 280                 tid = qos[0] & 0x0f;
 281         else
 282                 tid = 0;
 283         if (tk) {
 284                 if (os_memcmp(hdr->addr2, tdls->init->addr, ETH_ALEN) == 0)
 285                         rsc = tdls->rsc_init[tid];
 286                 else
 287                         rsc = tdls->rsc_resp[tid];
 288         } else if (fc & WLAN_FC_TODS)
 289                 rsc = sta->rsc_tods[tid];
 290         else
 291                 rsc = sta->rsc_fromds[tid];
 292
 293
 294         if (tk == NULL && sta->pairwise_cipher == WPA_CIPHER_TKIP)
 295                 tkip_get_pn(pn, data);
 296         else
 297                 ccmp_get_pn(pn, data);
 298         if (os_memcmp(pn, rsc, 6) <= 0) {
 299                 wpa_printf(MSG_INFO, "CCMP/TKIP replay detected: SA=" MACSTR,
 300                            MAC2STR(hdr->addr2));
 301                 wpa_hexdump(MSG_INFO, "RX PN", pn, 6);
 302                 wpa_hexdump(MSG_INFO, "RSC", rsc, 6);
 303         }
 304
 305         if (tk)
 306                 decrypted = ccmp_decrypt(tk, hdr, data, len, &dlen);
 307         else if (sta->pairwise_cipher == WPA_CIPHER_TKIP)
 308                 decrypted = tkip_decrypt(sta->ptk.tk1, hdr, data, len, &dlen);
 309         else
 310                 decrypted = ccmp_decrypt(sta->ptk.tk1, hdr, data, len, &dlen);
 311         if (decrypted) {
 312                 rx_data_process(wt, bss->bssid, sta->addr, dst, src, decrypted,
 313                                 dlen, 1);
 314                 os_memcpy(rsc, pn, 6);
 315                 write_pcap_decrypted(wt, (const u8 *) hdr, 24 + (qos ? 2 : 0),
 316                                      decrypted, dlen);
 317         }
 318         os_free(decrypted);
 319 }
 320
 321
 322 static void rx_data_bss(struct wlantest *wt, const struct ieee80211_hdr *hdr,
 323                         const u8 *qos, const u8 *dst, const u8 *src,
 324                         const u8 *data, size_t len)
 325 {
 326         u16 fc = le_to_host16(hdr->frame_control);
 327         int prot = !!(fc & WLAN_FC_ISWEP);
 328
 329         if (qos) {
 330                 u8 ack = (qos[0] & 0x60) >> 5;
 331                 wpa_printf(MSG_MSGDUMP, "BSS DATA: " MACSTR " -> " MACSTR
 332                            " len=%u%s tid=%u%s%s",
 333                            MAC2STR(src), MAC2STR(dst), (unsigned int) len,
 334                            prot ? " Prot" : "", qos[0] & 0x0f,
 335                            (qos[0] & 0x10) ? " EOSP" : "",
 336                            ack == 0 ? "" :
 337                            (ack == 1 ? " NoAck" :
 338                             (ack == 2 ? " NoExpAck" : " BA")));
 339         } else {
 340                 wpa_printf(MSG_MSGDUMP, "BSS DATA: " MACSTR " -> " MACSTR
 341                            " len=%u%s",
 342                            MAC2STR(src), MAC2STR(dst), (unsigned int) len,
 343                            prot ? " Prot" : "");
 344         }
 345
 346         if (prot)
 347                 rx_data_bss_prot(wt, hdr, qos, dst, src, data, len);
 348         else {
 349                 const u8 *bssid, *sta_addr;
 350                 if (fc & WLAN_FC_TODS) {
 351                         bssid = hdr->addr1;
 352                         sta_addr = hdr->addr2;
 353                 } else {
 354                         bssid = hdr->addr2;
 355                         sta_addr = hdr->addr1;
 356                 }
 357                 rx_data_process(wt, bssid, sta_addr, dst, src, data, len, 0);
 358         }
 359 }
 360
 361
 362 static struct wlantest_tdls * get_tdls(struct wlantest *wt, const u8 *bssid,
 363                                        const u8 *sta1_addr,
 364                                        const u8 *sta2_addr)
 365 {
 366         struct wlantest_bss *bss;
 367         struct wlantest_sta *sta1, *sta2;
 368         struct wlantest_tdls *tdls;
 369
 370         bss = bss_find(wt, bssid);
 371         if (bss == NULL)
 372                 return NULL;
 373         sta1 = sta_find(bss, sta1_addr);
 374         if (sta1 == NULL)
 375                 return NULL;
 376         sta2 = sta_find(bss, sta2_addr);
 377         if (sta2 == NULL)
 378                 return NULL;
 379
 380         dl_list_for_each(tdls, &bss->tdls, struct wlantest_tdls, list) {
 381                 if ((tdls->init == sta1 && tdls->resp == sta2) ||
 382                     (tdls->init == sta2 && tdls->resp == sta1))
 383                         return tdls;
 384         }
 385
 386         return NULL;
 387 }
 388
 389
 390 static void add_direct_link(struct wlantest *wt, const u8 *bssid,
 391                             const u8 *sta1_addr, const u8 *sta2_addr)
 392 {
 393         struct wlantest_tdls *tdls;
 394
 395         tdls = get_tdls(wt, bssid, sta1_addr, sta2_addr);
 396         if (tdls == NULL)
 397                 return;
 398
 399         if (tdls->link_up)
 400                 tdls->counters[WLANTEST_TDLS_COUNTER_VALID_DIRECT_LINK]++;
 401         else
 402                 tdls->counters[WLANTEST_TDLS_COUNTER_INVALID_DIRECT_LINK]++;
 403 }
 404
 405
 406 static void add_ap_path(struct wlantest *wt, const u8 *bssid,
 407                         const u8 *sta1_addr, const u8 *sta2_addr)
 408 {
 409         struct wlantest_tdls *tdls;
 410
 411         tdls = get_tdls(wt, bssid, sta1_addr, sta2_addr);
 412         if (tdls == NULL)
 413                 return;
 414
 415         if (tdls->link_up)
 416                 tdls->counters[WLANTEST_TDLS_COUNTER_INVALID_AP_PATH]++;
 417         else
 418                 tdls->counters[WLANTEST_TDLS_COUNTER_VALID_AP_PATH]++;
 419 }
 420
 421
 422 void rx_data(struct wlantest *wt, const u8 *data, size_t len)
 423 {
 424         const struct ieee80211_hdr *hdr;
 425         u16 fc, stype;
 426         size_t hdrlen;
 427         const u8 *qos = NULL;
 428
 429         if (len < 24)
 430                 return;
 431
 432         hdr = (const struct ieee80211_hdr *) data;
 433         fc = le_to_host16(hdr->frame_control);
 434         stype = WLAN_FC_GET_STYPE(fc);
 435         hdrlen = 24;
 436         if ((fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) ==
 437             (WLAN_FC_TODS | WLAN_FC_FROMDS))
 438                 hdrlen += ETH_ALEN;
 439         if (stype & 0x08) {
 440                 qos = data + hdrlen;
 441                 hdrlen += 2;
 442         }
 443         if (len < hdrlen)
 444                 return;
 445         wt->rx_data++;
 446
 447         switch (fc & (WLAN_FC_TODS | WLAN_FC_FROMDS)) {
 448         case 0:
 449                 wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s IBSS DA=" MACSTR " SA="
 450                            MACSTR " BSSID=" MACSTR,
 451                            data_stype(WLAN_FC_GET_STYPE(fc)),
 452                            fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
 453                            fc & WLAN_FC_ISWEP ? " Prot" : "",
 454                            MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
 455                            MAC2STR(hdr->addr3));
 456                 add_direct_link(wt, hdr->addr3, hdr->addr1, hdr->addr2);
 457                 rx_data_bss(wt, hdr, qos, hdr->addr1, hdr->addr2,
 458                             data + hdrlen, len - hdrlen);
 459                 break;
 460         case WLAN_FC_FROMDS:
 461                 wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s FromDS DA=" MACSTR
 462                            " BSSID=" MACSTR " SA=" MACSTR,
 463                            data_stype(WLAN_FC_GET_STYPE(fc)),
 464                            fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
 465                            fc & WLAN_FC_ISWEP ? " Prot" : "",
 466                            MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
 467                            MAC2STR(hdr->addr3));
 468                 add_ap_path(wt, hdr->addr2, hdr->addr1, hdr->addr3);
 469                 rx_data_bss(wt, hdr, qos, hdr->addr1, hdr->addr2,
 470                             data + hdrlen, len - hdrlen);
 471                 break;
 472         case WLAN_FC_TODS:
 473                 wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s ToDS BSSID=" MACSTR
 474                            " SA=" MACSTR " DA=" MACSTR,
 475                            data_stype(WLAN_FC_GET_STYPE(fc)),
 476                            fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
 477                            fc & WLAN_FC_ISWEP ? " Prot" : "",
 478                            MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
 479                            MAC2STR(hdr->addr3));
 480                 add_ap_path(wt, hdr->addr1, hdr->addr3, hdr->addr2);
 481                 rx_data_bss(wt, hdr, qos, hdr->addr3, hdr->addr2,
 482                             data + hdrlen, len - hdrlen);
 483                 break;
 484         case WLAN_FC_TODS | WLAN_FC_FROMDS:
 485                 wpa_printf(MSG_EXCESSIVE, "DATA %s%s%s WDS RA=" MACSTR " TA="
 486                            MACSTR " DA=" MACSTR " SA=" MACSTR,
 487                            data_stype(WLAN_FC_GET_STYPE(fc)),
 488                            fc & WLAN_FC_PWRMGT ? " PwrMgt" : "",
 489                            fc & WLAN_FC_ISWEP ? " Prot" : "",
 490                            MAC2STR(hdr->addr1), MAC2STR(hdr->addr2),
 491                            MAC2STR(hdr->addr3),
 492                            MAC2STR((const u8 *) (hdr + 1)));
 493                 break;
 494         }
 495 }