linux/net/wireless/util.c
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   1/*
   2 * Wireless utility functions
   3 *
   4 * Copyright 2007-2009  Johannes Berg <johannes@sipsolutions.net>
   5 */
   6#include <linux/bitops.h>
   7#include <linux/etherdevice.h>
   8#include <linux/slab.h>
   9#include <net/cfg80211.h>
  10#include <net/ip.h>
  11#include "core.h"
  12
  13struct ieee80211_rate *
  14ieee80211_get_response_rate(struct ieee80211_supported_band *sband,
  15                            u32 basic_rates, int bitrate)
  16{
  17        struct ieee80211_rate *result = &sband->bitrates[0];
  18        int i;
  19
  20        for (i = 0; i < sband->n_bitrates; i++) {
  21                if (!(basic_rates & BIT(i)))
  22                        continue;
  23                if (sband->bitrates[i].bitrate > bitrate)
  24                        continue;
  25                result = &sband->bitrates[i];
  26        }
  27
  28        return result;
  29}
  30EXPORT_SYMBOL(ieee80211_get_response_rate);
  31
  32int ieee80211_channel_to_frequency(int chan, enum ieee80211_band band)
  33{
  34        /* see 802.11 17.3.8.3.2 and Annex J
  35         * there are overlapping channel numbers in 5GHz and 2GHz bands */
  36        if (band == IEEE80211_BAND_5GHZ) {
  37                if (chan >= 182 && chan <= 196)
  38                        return 4000 + chan * 5;
  39                else
  40                        return 5000 + chan * 5;
  41        } else { /* IEEE80211_BAND_2GHZ */
  42                if (chan == 14)
  43                        return 2484;
  44                else if (chan < 14)
  45                        return 2407 + chan * 5;
  46                else
  47                        return 0; /* not supported */
  48        }
  49}
  50EXPORT_SYMBOL(ieee80211_channel_to_frequency);
  51
  52int ieee80211_frequency_to_channel(int freq)
  53{
  54        /* see 802.11 17.3.8.3.2 and Annex J */
  55        if (freq == 2484)
  56                return 14;
  57        else if (freq < 2484)
  58                return (freq - 2407) / 5;
  59        else if (freq >= 4910 && freq <= 4980)
  60                return (freq - 4000) / 5;
  61        else
  62                return (freq - 5000) / 5;
  63}
  64EXPORT_SYMBOL(ieee80211_frequency_to_channel);
  65
  66struct ieee80211_channel *__ieee80211_get_channel(struct wiphy *wiphy,
  67                                                  int freq)
  68{
  69        enum ieee80211_band band;
  70        struct ieee80211_supported_band *sband;
  71        int i;
  72
  73        for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
  74                sband = wiphy->bands[band];
  75
  76                if (!sband)
  77                        continue;
  78
  79                for (i = 0; i < sband->n_channels; i++) {
  80                        if (sband->channels[i].center_freq == freq)
  81                                return &sband->channels[i];
  82                }
  83        }
  84
  85        return NULL;
  86}
  87EXPORT_SYMBOL(__ieee80211_get_channel);
  88
  89static void set_mandatory_flags_band(struct ieee80211_supported_band *sband,
  90                                     enum ieee80211_band band)
  91{
  92        int i, want;
  93
  94        switch (band) {
  95        case IEEE80211_BAND_5GHZ:
  96                want = 3;
  97                for (i = 0; i < sband->n_bitrates; i++) {
  98                        if (sband->bitrates[i].bitrate == 60 ||
  99                            sband->bitrates[i].bitrate == 120 ||
 100                            sband->bitrates[i].bitrate == 240) {
 101                                sband->bitrates[i].flags |=
 102                                        IEEE80211_RATE_MANDATORY_A;
 103                                want--;
 104                        }
 105                }
 106                WARN_ON(want);
 107                break;
 108        case IEEE80211_BAND_2GHZ:
 109                want = 7;
 110                for (i = 0; i < sband->n_bitrates; i++) {
 111                        if (sband->bitrates[i].bitrate == 10) {
 112                                sband->bitrates[i].flags |=
 113                                        IEEE80211_RATE_MANDATORY_B |
 114                                        IEEE80211_RATE_MANDATORY_G;
 115                                want--;
 116                        }
 117
 118                        if (sband->bitrates[i].bitrate == 20 ||
 119                            sband->bitrates[i].bitrate == 55 ||
 120                            sband->bitrates[i].bitrate == 110 ||
 121                            sband->bitrates[i].bitrate == 60 ||
 122                            sband->bitrates[i].bitrate == 120 ||
 123                            sband->bitrates[i].bitrate == 240) {
 124                                sband->bitrates[i].flags |=
 125                                        IEEE80211_RATE_MANDATORY_G;
 126                                want--;
 127                        }
 128
 129                        if (sband->bitrates[i].bitrate != 10 &&
 130                            sband->bitrates[i].bitrate != 20 &&
 131                            sband->bitrates[i].bitrate != 55 &&
 132                            sband->bitrates[i].bitrate != 110)
 133                                sband->bitrates[i].flags |=
 134                                        IEEE80211_RATE_ERP_G;
 135                }
 136                WARN_ON(want != 0 && want != 3 && want != 6);
 137                break;
 138        case IEEE80211_NUM_BANDS:
 139                WARN_ON(1);
 140                break;
 141        }
 142}
 143
 144void ieee80211_set_bitrate_flags(struct wiphy *wiphy)
 145{
 146        enum ieee80211_band band;
 147
 148        for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 149                if (wiphy->bands[band])
 150                        set_mandatory_flags_band(wiphy->bands[band], band);
 151}
 152
 153int cfg80211_validate_key_settings(struct cfg80211_registered_device *rdev,
 154                                   struct key_params *params, int key_idx,
 155                                   bool pairwise, const u8 *mac_addr)
 156{
 157        int i;
 158
 159        if (key_idx > 5)
 160                return -EINVAL;
 161
 162        if (!pairwise && mac_addr && !(rdev->wiphy.flags & WIPHY_FLAG_IBSS_RSN))
 163                return -EINVAL;
 164
 165        if (pairwise && !mac_addr)
 166                return -EINVAL;
 167
 168        /*
 169         * Disallow pairwise keys with non-zero index unless it's WEP
 170         * or a vendor specific cipher (because current deployments use
 171         * pairwise WEP keys with non-zero indices and for vendor specific
 172         * ciphers this should be validated in the driver or hardware level
 173         * - but 802.11i clearly specifies to use zero)
 174         */
 175        if (pairwise && key_idx &&
 176            ((params->cipher == WLAN_CIPHER_SUITE_TKIP) ||
 177             (params->cipher == WLAN_CIPHER_SUITE_CCMP) ||
 178             (params->cipher == WLAN_CIPHER_SUITE_AES_CMAC)))
 179                return -EINVAL;
 180
 181        switch (params->cipher) {
 182        case WLAN_CIPHER_SUITE_WEP40:
 183                if (params->key_len != WLAN_KEY_LEN_WEP40)
 184                        return -EINVAL;
 185                break;
 186        case WLAN_CIPHER_SUITE_TKIP:
 187                if (params->key_len != WLAN_KEY_LEN_TKIP)
 188                        return -EINVAL;
 189                break;
 190        case WLAN_CIPHER_SUITE_CCMP:
 191                if (params->key_len != WLAN_KEY_LEN_CCMP)
 192                        return -EINVAL;
 193                break;
 194        case WLAN_CIPHER_SUITE_WEP104:
 195                if (params->key_len != WLAN_KEY_LEN_WEP104)
 196                        return -EINVAL;
 197                break;
 198        case WLAN_CIPHER_SUITE_AES_CMAC:
 199                if (params->key_len != WLAN_KEY_LEN_AES_CMAC)
 200                        return -EINVAL;
 201                break;
 202        default:
 203                /*
 204                 * We don't know anything about this algorithm,
 205                 * allow using it -- but the driver must check
 206                 * all parameters! We still check below whether
 207                 * or not the driver supports this algorithm,
 208                 * of course.
 209                 */
 210                break;
 211        }
 212
 213        if (params->seq) {
 214                switch (params->cipher) {
 215                case WLAN_CIPHER_SUITE_WEP40:
 216                case WLAN_CIPHER_SUITE_WEP104:
 217                        /* These ciphers do not use key sequence */
 218                        return -EINVAL;
 219                case WLAN_CIPHER_SUITE_TKIP:
 220                case WLAN_CIPHER_SUITE_CCMP:
 221                case WLAN_CIPHER_SUITE_AES_CMAC:
 222                        if (params->seq_len != 6)
 223                                return -EINVAL;
 224                        break;
 225                }
 226        }
 227
 228        for (i = 0; i < rdev->wiphy.n_cipher_suites; i++)
 229                if (params->cipher == rdev->wiphy.cipher_suites[i])
 230                        break;
 231        if (i == rdev->wiphy.n_cipher_suites)
 232                return -EINVAL;
 233
 234        return 0;
 235}
 236
 237/* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 238/* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 239const unsigned char rfc1042_header[] __aligned(2) =
 240        { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
 241EXPORT_SYMBOL(rfc1042_header);
 242
 243/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
 244const unsigned char bridge_tunnel_header[] __aligned(2) =
 245        { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
 246EXPORT_SYMBOL(bridge_tunnel_header);
 247
 248unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc)
 249{
 250        unsigned int hdrlen = 24;
 251
 252        if (ieee80211_is_data(fc)) {
 253                if (ieee80211_has_a4(fc))
 254                        hdrlen = 30;
 255                if (ieee80211_is_data_qos(fc)) {
 256                        hdrlen += IEEE80211_QOS_CTL_LEN;
 257                        if (ieee80211_has_order(fc))
 258                                hdrlen += IEEE80211_HT_CTL_LEN;
 259                }
 260                goto out;
 261        }
 262
 263        if (ieee80211_is_ctl(fc)) {
 264                /*
 265                 * ACK and CTS are 10 bytes, all others 16. To see how
 266                 * to get this condition consider
 267                 *   subtype mask:   0b0000000011110000 (0x00F0)
 268                 *   ACK subtype:    0b0000000011010000 (0x00D0)
 269                 *   CTS subtype:    0b0000000011000000 (0x00C0)
 270                 *   bits that matter:         ^^^      (0x00E0)
 271                 *   value of those: 0b0000000011000000 (0x00C0)
 272                 */
 273                if ((fc & cpu_to_le16(0x00E0)) == cpu_to_le16(0x00C0))
 274                        hdrlen = 10;
 275                else
 276                        hdrlen = 16;
 277        }
 278out:
 279        return hdrlen;
 280}
 281EXPORT_SYMBOL(ieee80211_hdrlen);
 282
 283unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb)
 284{
 285        const struct ieee80211_hdr *hdr =
 286                        (const struct ieee80211_hdr *)skb->data;
 287        unsigned int hdrlen;
 288
 289        if (unlikely(skb->len < 10))
 290                return 0;
 291        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 292        if (unlikely(hdrlen > skb->len))
 293                return 0;
 294        return hdrlen;
 295}
 296EXPORT_SYMBOL(ieee80211_get_hdrlen_from_skb);
 297
 298static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
 299{
 300        int ae = meshhdr->flags & MESH_FLAGS_AE;
 301        /* 7.1.3.5a.2 */
 302        switch (ae) {
 303        case 0:
 304                return 6;
 305        case MESH_FLAGS_AE_A4:
 306                return 12;
 307        case MESH_FLAGS_AE_A5_A6:
 308                return 18;
 309        case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
 310                return 24;
 311        default:
 312                return 6;
 313        }
 314}
 315
 316int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
 317                           enum nl80211_iftype iftype)
 318{
 319        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 320        u16 hdrlen, ethertype;
 321        u8 *payload;
 322        u8 dst[ETH_ALEN];
 323        u8 src[ETH_ALEN] __aligned(2);
 324
 325        if (unlikely(!ieee80211_is_data_present(hdr->frame_control)))
 326                return -1;
 327
 328        hdrlen = ieee80211_hdrlen(hdr->frame_control);
 329
 330        /* convert IEEE 802.11 header + possible LLC headers into Ethernet
 331         * header
 332         * IEEE 802.11 address fields:
 333         * ToDS FromDS Addr1 Addr2 Addr3 Addr4
 334         *   0     0   DA    SA    BSSID n/a
 335         *   0     1   DA    BSSID SA    n/a
 336         *   1     0   BSSID SA    DA    n/a
 337         *   1     1   RA    TA    DA    SA
 338         */
 339        memcpy(dst, ieee80211_get_DA(hdr), ETH_ALEN);
 340        memcpy(src, ieee80211_get_SA(hdr), ETH_ALEN);
 341
 342        switch (hdr->frame_control &
 343                cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
 344        case cpu_to_le16(IEEE80211_FCTL_TODS):
 345                if (unlikely(iftype != NL80211_IFTYPE_AP &&
 346                             iftype != NL80211_IFTYPE_AP_VLAN &&
 347                             iftype != NL80211_IFTYPE_P2P_GO))
 348                        return -1;
 349                break;
 350        case cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS):
 351                if (unlikely(iftype != NL80211_IFTYPE_WDS &&
 352                             iftype != NL80211_IFTYPE_MESH_POINT &&
 353                             iftype != NL80211_IFTYPE_AP_VLAN &&
 354                             iftype != NL80211_IFTYPE_STATION))
 355                        return -1;
 356                if (iftype == NL80211_IFTYPE_MESH_POINT) {
 357                        struct ieee80211s_hdr *meshdr =
 358                                (struct ieee80211s_hdr *) (skb->data + hdrlen);
 359                        /* make sure meshdr->flags is on the linear part */
 360                        if (!pskb_may_pull(skb, hdrlen + 1))
 361                                return -1;
 362                        if (meshdr->flags & MESH_FLAGS_AE_A5_A6) {
 363                                skb_copy_bits(skb, hdrlen +
 364                                        offsetof(struct ieee80211s_hdr, eaddr1),
 365                                        dst, ETH_ALEN);
 366                                skb_copy_bits(skb, hdrlen +
 367                                        offsetof(struct ieee80211s_hdr, eaddr2),
 368                                        src, ETH_ALEN);
 369                        }
 370                        hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 371                }
 372                break;
 373        case cpu_to_le16(IEEE80211_FCTL_FROMDS):
 374                if ((iftype != NL80211_IFTYPE_STATION &&
 375                     iftype != NL80211_IFTYPE_P2P_CLIENT &&
 376                     iftype != NL80211_IFTYPE_MESH_POINT) ||
 377                    (is_multicast_ether_addr(dst) &&
 378                     !compare_ether_addr(src, addr)))
 379                        return -1;
 380                if (iftype == NL80211_IFTYPE_MESH_POINT) {
 381                        struct ieee80211s_hdr *meshdr =
 382                                (struct ieee80211s_hdr *) (skb->data + hdrlen);
 383                        /* make sure meshdr->flags is on the linear part */
 384                        if (!pskb_may_pull(skb, hdrlen + 1))
 385                                return -1;
 386                        if (meshdr->flags & MESH_FLAGS_AE_A4)
 387                                skb_copy_bits(skb, hdrlen +
 388                                        offsetof(struct ieee80211s_hdr, eaddr1),
 389                                        src, ETH_ALEN);
 390                        hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
 391                }
 392                break;
 393        case cpu_to_le16(0):
 394                if (iftype != NL80211_IFTYPE_ADHOC)
 395                        return -1;
 396                break;
 397        }
 398
 399        if (!pskb_may_pull(skb, hdrlen + 8))
 400                return -1;
 401
 402        payload = skb->data + hdrlen;
 403        ethertype = (payload[6] << 8) | payload[7];
 404
 405        if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 406                    ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 407                   compare_ether_addr(payload, bridge_tunnel_header) == 0)) {
 408                /* remove RFC1042 or Bridge-Tunnel encapsulation and
 409                 * replace EtherType */
 410                skb_pull(skb, hdrlen + 6);
 411                memcpy(skb_push(skb, ETH_ALEN), src, ETH_ALEN);
 412                memcpy(skb_push(skb, ETH_ALEN), dst, ETH_ALEN);
 413        } else {
 414                struct ethhdr *ehdr;
 415                __be16 len;
 416
 417                skb_pull(skb, hdrlen);
 418                len = htons(skb->len);
 419                ehdr = (struct ethhdr *) skb_push(skb, sizeof(struct ethhdr));
 420                memcpy(ehdr->h_dest, dst, ETH_ALEN);
 421                memcpy(ehdr->h_source, src, ETH_ALEN);
 422                ehdr->h_proto = len;
 423        }
 424        return 0;
 425}
 426EXPORT_SYMBOL(ieee80211_data_to_8023);
 427
 428int ieee80211_data_from_8023(struct sk_buff *skb, const u8 *addr,
 429                             enum nl80211_iftype iftype, u8 *bssid, bool qos)
 430{
 431        struct ieee80211_hdr hdr;
 432        u16 hdrlen, ethertype;
 433        __le16 fc;
 434        const u8 *encaps_data;
 435        int encaps_len, skip_header_bytes;
 436        int nh_pos, h_pos;
 437        int head_need;
 438
 439        if (unlikely(skb->len < ETH_HLEN))
 440                return -EINVAL;
 441
 442        nh_pos = skb_network_header(skb) - skb->data;
 443        h_pos = skb_transport_header(skb) - skb->data;
 444
 445        /* convert Ethernet header to proper 802.11 header (based on
 446         * operation mode) */
 447        ethertype = (skb->data[12] << 8) | skb->data[13];
 448        fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
 449
 450        switch (iftype) {
 451        case NL80211_IFTYPE_AP:
 452        case NL80211_IFTYPE_AP_VLAN:
 453        case NL80211_IFTYPE_P2P_GO:
 454                fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
 455                /* DA BSSID SA */
 456                memcpy(hdr.addr1, skb->data, ETH_ALEN);
 457                memcpy(hdr.addr2, addr, ETH_ALEN);
 458                memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
 459                hdrlen = 24;
 460                break;
 461        case NL80211_IFTYPE_STATION:
 462        case NL80211_IFTYPE_P2P_CLIENT:
 463                fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
 464                /* BSSID SA DA */
 465                memcpy(hdr.addr1, bssid, ETH_ALEN);
 466                memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 467                memcpy(hdr.addr3, skb->data, ETH_ALEN);
 468                hdrlen = 24;
 469                break;
 470        case NL80211_IFTYPE_ADHOC:
 471                /* DA SA BSSID */
 472                memcpy(hdr.addr1, skb->data, ETH_ALEN);
 473                memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
 474                memcpy(hdr.addr3, bssid, ETH_ALEN);
 475                hdrlen = 24;
 476                break;
 477        default:
 478                return -EOPNOTSUPP;
 479        }
 480
 481        if (qos) {
 482                fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
 483                hdrlen += 2;
 484        }
 485
 486        hdr.frame_control = fc;
 487        hdr.duration_id = 0;
 488        hdr.seq_ctrl = 0;
 489
 490        skip_header_bytes = ETH_HLEN;
 491        if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 492                encaps_data = bridge_tunnel_header;
 493                encaps_len = sizeof(bridge_tunnel_header);
 494                skip_header_bytes -= 2;
 495        } else if (ethertype > 0x600) {
 496                encaps_data = rfc1042_header;
 497                encaps_len = sizeof(rfc1042_header);
 498                skip_header_bytes -= 2;
 499        } else {
 500                encaps_data = NULL;
 501                encaps_len = 0;
 502        }
 503
 504        skb_pull(skb, skip_header_bytes);
 505        nh_pos -= skip_header_bytes;
 506        h_pos -= skip_header_bytes;
 507
 508        head_need = hdrlen + encaps_len - skb_headroom(skb);
 509
 510        if (head_need > 0 || skb_cloned(skb)) {
 511                head_need = max(head_need, 0);
 512                if (head_need)
 513                        skb_orphan(skb);
 514
 515                if (pskb_expand_head(skb, head_need, 0, GFP_ATOMIC)) {
 516                        pr_err("failed to reallocate Tx buffer\n");
 517                        return -ENOMEM;
 518                }
 519                skb->truesize += head_need;
 520        }
 521
 522        if (encaps_data) {
 523                memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 524                nh_pos += encaps_len;
 525                h_pos += encaps_len;
 526        }
 527
 528        memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
 529
 530        nh_pos += hdrlen;
 531        h_pos += hdrlen;
 532
 533        /* Update skb pointers to various headers since this modified frame
 534         * is going to go through Linux networking code that may potentially
 535         * need things like pointer to IP header. */
 536        skb_set_mac_header(skb, 0);
 537        skb_set_network_header(skb, nh_pos);
 538        skb_set_transport_header(skb, h_pos);
 539
 540        return 0;
 541}
 542EXPORT_SYMBOL(ieee80211_data_from_8023);
 543
 544
 545void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
 546                              const u8 *addr, enum nl80211_iftype iftype,
 547                              const unsigned int extra_headroom,
 548                              bool has_80211_header)
 549{
 550        struct sk_buff *frame = NULL;
 551        u16 ethertype;
 552        u8 *payload;
 553        const struct ethhdr *eth;
 554        int remaining, err;
 555        u8 dst[ETH_ALEN], src[ETH_ALEN];
 556
 557        if (has_80211_header) {
 558                err = ieee80211_data_to_8023(skb, addr, iftype);
 559                if (err)
 560                        goto out;
 561
 562                /* skip the wrapping header */
 563                eth = (struct ethhdr *) skb_pull(skb, sizeof(struct ethhdr));
 564                if (!eth)
 565                        goto out;
 566        } else {
 567                eth = (struct ethhdr *) skb->data;
 568        }
 569
 570        while (skb != frame) {
 571                u8 padding;
 572                __be16 len = eth->h_proto;
 573                unsigned int subframe_len = sizeof(struct ethhdr) + ntohs(len);
 574
 575                remaining = skb->len;
 576                memcpy(dst, eth->h_dest, ETH_ALEN);
 577                memcpy(src, eth->h_source, ETH_ALEN);
 578
 579                padding = (4 - subframe_len) & 0x3;
 580                /* the last MSDU has no padding */
 581                if (subframe_len > remaining)
 582                        goto purge;
 583
 584                skb_pull(skb, sizeof(struct ethhdr));
 585                /* reuse skb for the last subframe */
 586                if (remaining <= subframe_len + padding)
 587                        frame = skb;
 588                else {
 589                        unsigned int hlen = ALIGN(extra_headroom, 4);
 590                        /*
 591                         * Allocate and reserve two bytes more for payload
 592                         * alignment since sizeof(struct ethhdr) is 14.
 593                         */
 594                        frame = dev_alloc_skb(hlen + subframe_len + 2);
 595                        if (!frame)
 596                                goto purge;
 597
 598                        skb_reserve(frame, hlen + sizeof(struct ethhdr) + 2);
 599                        memcpy(skb_put(frame, ntohs(len)), skb->data,
 600                                ntohs(len));
 601
 602                        eth = (struct ethhdr *)skb_pull(skb, ntohs(len) +
 603                                                        padding);
 604                        if (!eth) {
 605                                dev_kfree_skb(frame);
 606                                goto purge;
 607                        }
 608                }
 609
 610                skb_reset_network_header(frame);
 611                frame->dev = skb->dev;
 612                frame->priority = skb->priority;
 613
 614                payload = frame->data;
 615                ethertype = (payload[6] << 8) | payload[7];
 616
 617                if (likely((compare_ether_addr(payload, rfc1042_header) == 0 &&
 618                            ethertype != ETH_P_AARP && ethertype != ETH_P_IPX) ||
 619                           compare_ether_addr(payload,
 620                                              bridge_tunnel_header) == 0)) {
 621                        /* remove RFC1042 or Bridge-Tunnel
 622                         * encapsulation and replace EtherType */
 623                        skb_pull(frame, 6);
 624                        memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 625                        memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 626                } else {
 627                        memcpy(skb_push(frame, sizeof(__be16)), &len,
 628                                sizeof(__be16));
 629                        memcpy(skb_push(frame, ETH_ALEN), src, ETH_ALEN);
 630                        memcpy(skb_push(frame, ETH_ALEN), dst, ETH_ALEN);
 631                }
 632                __skb_queue_tail(list, frame);
 633        }
 634
 635        return;
 636
 637 purge:
 638        __skb_queue_purge(list);
 639 out:
 640        dev_kfree_skb(skb);
 641}
 642EXPORT_SYMBOL(ieee80211_amsdu_to_8023s);
 643
 644/* Given a data frame determine the 802.1p/1d tag to use. */
 645unsigned int cfg80211_classify8021d(struct sk_buff *skb)
 646{
 647        unsigned int dscp;
 648
 649        /* skb->priority values from 256->263 are magic values to
 650         * directly indicate a specific 802.1d priority.  This is used
 651         * to allow 802.1d priority to be passed directly in from VLAN
 652         * tags, etc.
 653         */
 654        if (skb->priority >= 256 && skb->priority <= 263)
 655                return skb->priority - 256;
 656
 657        switch (skb->protocol) {
 658        case htons(ETH_P_IP):
 659                dscp = ip_hdr(skb)->tos & 0xfc;
 660                break;
 661        default:
 662                return 0;
 663        }
 664
 665        return dscp >> 5;
 666}
 667EXPORT_SYMBOL(cfg80211_classify8021d);
 668
 669const u8 *ieee80211_bss_get_ie(struct cfg80211_bss *bss, u8 ie)
 670{
 671        u8 *end, *pos;
 672
 673        pos = bss->information_elements;
 674        if (pos == NULL)
 675                return NULL;
 676        end = pos + bss->len_information_elements;
 677
 678        while (pos + 1 < end) {
 679                if (pos + 2 + pos[1] > end)
 680                        break;
 681                if (pos[0] == ie)
 682                        return pos;
 683                pos += 2 + pos[1];
 684        }
 685
 686        return NULL;
 687}
 688EXPORT_SYMBOL(ieee80211_bss_get_ie);
 689
 690void cfg80211_upload_connect_keys(struct wireless_dev *wdev)
 691{
 692        struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
 693        struct net_device *dev = wdev->netdev;
 694        int i;
 695
 696        if (!wdev->connect_keys)
 697                return;
 698
 699        for (i = 0; i < 6; i++) {
 700                if (!wdev->connect_keys->params[i].cipher)
 701                        continue;
 702                if (rdev->ops->add_key(wdev->wiphy, dev, i, false, NULL,
 703                                        &wdev->connect_keys->params[i])) {
 704                        netdev_err(dev, "failed to set key %d\n", i);
 705                        continue;
 706                }
 707                if (wdev->connect_keys->def == i)
 708                        if (rdev->ops->set_default_key(wdev->wiphy, dev,
 709                                                       i, true, true)) {
 710                                netdev_err(dev, "failed to set defkey %d\n", i);
 711                                continue;
 712                        }
 713                if (wdev->connect_keys->defmgmt == i)
 714                        if (rdev->ops->set_default_mgmt_key(wdev->wiphy, dev, i))
 715                                netdev_err(dev, "failed to set mgtdef %d\n", i);
 716        }
 717
 718        kfree(wdev->connect_keys);
 719        wdev->connect_keys = NULL;
 720}
 721
 722static void cfg80211_process_wdev_events(struct wireless_dev *wdev)
 723{
 724        struct cfg80211_event *ev;
 725        unsigned long flags;
 726        const u8 *bssid = NULL;
 727
 728        spin_lock_irqsave(&wdev->event_lock, flags);
 729        while (!list_empty(&wdev->event_list)) {
 730                ev = list_first_entry(&wdev->event_list,
 731                                      struct cfg80211_event, list);
 732                list_del(&ev->list);
 733                spin_unlock_irqrestore(&wdev->event_lock, flags);
 734
 735                wdev_lock(wdev);
 736                switch (ev->type) {
 737                case EVENT_CONNECT_RESULT:
 738                        if (!is_zero_ether_addr(ev->cr.bssid))
 739                                bssid = ev->cr.bssid;
 740                        __cfg80211_connect_result(
 741                                wdev->netdev, bssid,
 742                                ev->cr.req_ie, ev->cr.req_ie_len,
 743                                ev->cr.resp_ie, ev->cr.resp_ie_len,
 744                                ev->cr.status,
 745                                ev->cr.status == WLAN_STATUS_SUCCESS,
 746                                NULL);
 747                        break;
 748                case EVENT_ROAMED:
 749                        __cfg80211_roamed(wdev, ev->rm.channel, ev->rm.bssid,
 750                                          ev->rm.req_ie, ev->rm.req_ie_len,
 751                                          ev->rm.resp_ie, ev->rm.resp_ie_len);
 752                        break;
 753                case EVENT_DISCONNECTED:
 754                        __cfg80211_disconnected(wdev->netdev,
 755                                                ev->dc.ie, ev->dc.ie_len,
 756                                                ev->dc.reason, true);
 757                        break;
 758                case EVENT_IBSS_JOINED:
 759                        __cfg80211_ibss_joined(wdev->netdev, ev->ij.bssid);
 760                        break;
 761                }
 762                wdev_unlock(wdev);
 763
 764                kfree(ev);
 765
 766                spin_lock_irqsave(&wdev->event_lock, flags);
 767        }
 768        spin_unlock_irqrestore(&wdev->event_lock, flags);
 769}
 770
 771void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev)
 772{
 773        struct wireless_dev *wdev;
 774
 775        ASSERT_RTNL();
 776        ASSERT_RDEV_LOCK(rdev);
 777
 778        mutex_lock(&rdev->devlist_mtx);
 779
 780        list_for_each_entry(wdev, &rdev->netdev_list, list)
 781                cfg80211_process_wdev_events(wdev);
 782
 783        mutex_unlock(&rdev->devlist_mtx);
 784}
 785
 786int cfg80211_change_iface(struct cfg80211_registered_device *rdev,
 787                          struct net_device *dev, enum nl80211_iftype ntype,
 788                          u32 *flags, struct vif_params *params)
 789{
 790        int err;
 791        enum nl80211_iftype otype = dev->ieee80211_ptr->iftype;
 792
 793        ASSERT_RDEV_LOCK(rdev);
 794
 795        /* don't support changing VLANs, you just re-create them */
 796        if (otype == NL80211_IFTYPE_AP_VLAN)
 797                return -EOPNOTSUPP;
 798
 799        if (!rdev->ops->change_virtual_intf ||
 800            !(rdev->wiphy.interface_modes & (1 << ntype)))
 801                return -EOPNOTSUPP;
 802
 803        /* if it's part of a bridge, reject changing type to station/ibss */
 804        if ((dev->priv_flags & IFF_BRIDGE_PORT) &&
 805            (ntype == NL80211_IFTYPE_ADHOC ||
 806             ntype == NL80211_IFTYPE_STATION ||
 807             ntype == NL80211_IFTYPE_P2P_CLIENT))
 808                return -EBUSY;
 809
 810        if (ntype != otype) {
 811                err = cfg80211_can_change_interface(rdev, dev->ieee80211_ptr,
 812                                                    ntype);
 813                if (err)
 814                        return err;
 815
 816                dev->ieee80211_ptr->use_4addr = false;
 817                dev->ieee80211_ptr->mesh_id_up_len = 0;
 818
 819                switch (otype) {
 820                case NL80211_IFTYPE_ADHOC:
 821                        cfg80211_leave_ibss(rdev, dev, false);
 822                        break;
 823                case NL80211_IFTYPE_STATION:
 824                case NL80211_IFTYPE_P2P_CLIENT:
 825                        cfg80211_disconnect(rdev, dev,
 826                                            WLAN_REASON_DEAUTH_LEAVING, true);
 827                        break;
 828                case NL80211_IFTYPE_MESH_POINT:
 829                        /* mesh should be handled? */
 830                        break;
 831                default:
 832                        break;
 833                }
 834
 835                cfg80211_process_rdev_events(rdev);
 836        }
 837
 838        err = rdev->ops->change_virtual_intf(&rdev->wiphy, dev,
 839                                             ntype, flags, params);
 840
 841        WARN_ON(!err && dev->ieee80211_ptr->iftype != ntype);
 842
 843        if (!err && params && params->use_4addr != -1)
 844                dev->ieee80211_ptr->use_4addr = params->use_4addr;
 845
 846        if (!err) {
 847                dev->priv_flags &= ~IFF_DONT_BRIDGE;
 848                switch (ntype) {
 849                case NL80211_IFTYPE_STATION:
 850                        if (dev->ieee80211_ptr->use_4addr)
 851                                break;
 852                        /* fall through */
 853                case NL80211_IFTYPE_P2P_CLIENT:
 854                case NL80211_IFTYPE_ADHOC:
 855                        dev->priv_flags |= IFF_DONT_BRIDGE;
 856                        break;
 857                case NL80211_IFTYPE_P2P_GO:
 858                case NL80211_IFTYPE_AP:
 859                case NL80211_IFTYPE_AP_VLAN:
 860                case NL80211_IFTYPE_WDS:
 861                case NL80211_IFTYPE_MESH_POINT:
 862                        /* bridging OK */
 863                        break;
 864                case NL80211_IFTYPE_MONITOR:
 865                        /* monitor can't bridge anyway */
 866                        break;
 867                case NL80211_IFTYPE_UNSPECIFIED:
 868                case NUM_NL80211_IFTYPES:
 869                        /* not happening */
 870                        break;
 871                }
 872        }
 873
 874        return err;
 875}
 876
 877u16 cfg80211_calculate_bitrate(struct rate_info *rate)
 878{
 879        int modulation, streams, bitrate;
 880
 881        if (!(rate->flags & RATE_INFO_FLAGS_MCS))
 882                return rate->legacy;
 883
 884        /* the formula below does only work for MCS values smaller than 32 */
 885        if (rate->mcs >= 32)
 886                return 0;
 887
 888        modulation = rate->mcs & 7;
 889        streams = (rate->mcs >> 3) + 1;
 890
 891        bitrate = (rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH) ?
 892                        13500000 : 6500000;
 893
 894        if (modulation < 4)
 895                bitrate *= (modulation + 1);
 896        else if (modulation == 4)
 897                bitrate *= (modulation + 2);
 898        else
 899                bitrate *= (modulation + 3);
 900
 901        bitrate *= streams;
 902
 903        if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
 904                bitrate = (bitrate / 9) * 10;
 905
 906        /* do NOT round down here */
 907        return (bitrate + 50000) / 100000;
 908}
 909
 910int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev,
 911                                 u32 beacon_int)
 912{
 913        struct wireless_dev *wdev;
 914        int res = 0;
 915
 916        if (!beacon_int)
 917                return -EINVAL;
 918
 919        mutex_lock(&rdev->devlist_mtx);
 920
 921        list_for_each_entry(wdev, &rdev->netdev_list, list) {
 922                if (!wdev->beacon_interval)
 923                        continue;
 924                if (wdev->beacon_interval != beacon_int) {
 925                        res = -EINVAL;
 926                        break;
 927                }
 928        }
 929
 930        mutex_unlock(&rdev->devlist_mtx);
 931
 932        return res;
 933}
 934
 935int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev,
 936                                  struct wireless_dev *wdev,
 937                                  enum nl80211_iftype iftype)
 938{
 939        struct wireless_dev *wdev_iter;
 940        int num[NUM_NL80211_IFTYPES];
 941        int total = 1;
 942        int i, j;
 943
 944        ASSERT_RTNL();
 945
 946        /* Always allow software iftypes */
 947        if (rdev->wiphy.software_iftypes & BIT(iftype))
 948                return 0;
 949
 950        /*
 951         * Drivers will gradually all set this flag, until all
 952         * have it we only enforce for those that set it.
 953         */
 954        if (!(rdev->wiphy.flags & WIPHY_FLAG_ENFORCE_COMBINATIONS))
 955                return 0;
 956
 957        memset(num, 0, sizeof(num));
 958
 959        num[iftype] = 1;
 960
 961        mutex_lock(&rdev->devlist_mtx);
 962        list_for_each_entry(wdev_iter, &rdev->netdev_list, list) {
 963                if (wdev_iter == wdev)
 964                        continue;
 965                if (!netif_running(wdev_iter->netdev))
 966                        continue;
 967
 968                if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype))
 969                        continue;
 970
 971                num[wdev_iter->iftype]++;
 972                total++;
 973        }
 974        mutex_unlock(&rdev->devlist_mtx);
 975
 976        for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) {
 977                const struct ieee80211_iface_combination *c;
 978                struct ieee80211_iface_limit *limits;
 979
 980                c = &rdev->wiphy.iface_combinations[i];
 981
 982                limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits,
 983                                 GFP_KERNEL);
 984                if (!limits)
 985                        return -ENOMEM;
 986                if (total > c->max_interfaces)
 987                        goto cont;
 988
 989                for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) {
 990                        if (rdev->wiphy.software_iftypes & BIT(iftype))
 991                                continue;
 992                        for (j = 0; j < c->n_limits; j++) {
 993                                if (!(limits[j].types & iftype))
 994                                        continue;
 995                                if (limits[j].max < num[iftype])
 996                                        goto cont;
 997                                limits[j].max -= num[iftype];
 998                        }
 999                }
1000                /* yay, it fits */
1001                kfree(limits);
1002                return 0;
1003 cont:
1004                kfree(limits);
1005        }
1006
1007        return -EBUSY;
1008}
1009
1010int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
1011                           const u8 *rates, unsigned int n_rates,
1012                           u32 *mask)
1013{
1014        int i, j;
1015
1016        if (!sband)
1017                return -EINVAL;
1018
1019        if (n_rates == 0 || n_rates > NL80211_MAX_SUPP_RATES)
1020                return -EINVAL;
1021
1022        *mask = 0;
1023
1024        for (i = 0; i < n_rates; i++) {
1025                int rate = (rates[i] & 0x7f) * 5;
1026                bool found = false;
1027
1028                for (j = 0; j < sband->n_bitrates; j++) {
1029                        if (sband->bitrates[j].bitrate == rate) {
1030                                found = true;
1031                                *mask |= BIT(j);
1032                                break;
1033                        }
1034                }
1035                if (!found)
1036                        return -EINVAL;
1037        }
1038
1039        /*
1040         * mask must have at least one bit set here since we
1041         * didn't accept a 0-length rates array nor allowed
1042         * entries in the array that didn't exist
1043         */
1044
1045        return 0;
1046}
1047