include/linux/usb/wusb.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Wireless USB Standard Definitions
   4  * Event Size Tables
   5  *
   6  * Copyright (C) 2005-2006 Intel Corporation
   7  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License version
  11  * 2 as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21  * 02110-1301, USA.
  22  *
  23  *
  24  * FIXME: docs
  25  * FIXME: organize properly, group logically
  26  *
  27  * All the event structures are defined in uwb/spec.h, as they are
  28  * common to the WHCI and WUSB radio control interfaces.
  29  */
  30
  31 #ifndef __WUSB_H__
  32 #define __WUSB_H__
  33
  34 #include <linux/types.h>
  35 #include <linux/kernel.h>
  36 #include <linux/uwb/spec.h>
  37 #include <linux/usb/ch9.h>
  38 #include <linux/param.h>
  39
  40 /**
  41  * WUSB Information Element header
  42  *
  43  * I don't know why, they decided to make it different to the MBOA MAC
  44  * IE Header; beats me.
  45  */
  46 struct wuie_hdr {
  47         u8 bLength;
  48         u8 bIEIdentifier;
  49 } __attribute__((packed));
  50
  51 enum {
  52         WUIE_ID_WCTA = 0x80,
  53         WUIE_ID_CONNECTACK,
  54         WUIE_ID_HOST_INFO,
  55         WUIE_ID_CHANGE_ANNOUNCE,
  56         WUIE_ID_DEVICE_DISCONNECT,
  57         WUIE_ID_HOST_DISCONNECT,
  58         WUIE_ID_KEEP_ALIVE = 0x89,
  59         WUIE_ID_ISOCH_DISCARD,
  60         WUIE_ID_RESET_DEVICE,
  61 };
  62
  63 /**
  64  * Maximum number of array elements in a WUSB IE.
  65  *
  66  * WUSB1.0[7.5 before table 7-38] says that in WUSB IEs that
  67  * are "arrays" have to limited to 4 elements. So we define it
  68  * like that to ease up and submit only the neeed size.
  69  */
  70 #define WUIE_ELT_MAX 4
  71
  72 /**
  73  * Wrapper for the data that defines a CHID, a CDID or a CK
  74  *
  75  * WUSB defines that CHIDs, CDIDs and CKs are a 16 byte string of
  76  * data. In order to avoid confusion and enforce types, we wrap it.
  77  *
  78  * Make it packed, as we use it in some hw definitions.
  79  */
  80 struct wusb_ckhdid {
  81         u8 data[16];
  82 } __attribute__((packed));
  83
  84 static const struct wusb_ckhdid wusb_ckhdid_zero = { .data = { 0 } };
  85
  86 #define WUSB_CKHDID_STRSIZE (3 * sizeof(struct wusb_ckhdid) + 1)
  87
  88 /**
  89  * WUSB IE: Host Information (WUSB1.0[7.5.2])
  90  *
  91  * Used to provide information about the host to the Wireless USB
  92  * devices in range (CHID can be used as an ASCII string).
  93  */
  94 struct wuie_host_info {
  95         struct wuie_hdr hdr;
  96         __le16 attributes;
  97         struct wusb_ckhdid CHID;
  98 } __attribute__((packed));
  99
 100 /**
 101  * WUSB IE: Connect Ack (WUSB1.0[7.5.1])
 102  *
 103  * Used to acknowledge device connect requests. See note for
 104  * WUIE_ELT_MAX.
 105  */
 106 struct wuie_connect_ack {
 107         struct wuie_hdr hdr;
 108         struct {
 109                 struct wusb_ckhdid CDID;
 110                 u8 bDeviceAddress;      /* 0 means unused */
 111                 u8 bReserved;
 112         } blk[WUIE_ELT_MAX];
 113 } __attribute__((packed));
 114
 115 /**
 116  * WUSB IE Host Information Element, Connect Availability
 117  *
 118  * WUSB1.0[7.5.2], bmAttributes description
 119  */
 120 enum {
 121         WUIE_HI_CAP_RECONNECT = 0,
 122         WUIE_HI_CAP_LIMITED,
 123         WUIE_HI_CAP_RESERVED,
 124         WUIE_HI_CAP_ALL,
 125 };
 126
 127 /**
 128  * WUSB IE: Channel Stop (WUSB1.0[7.5.8])
 129  *
 130  * Tells devices the host is going to stop sending MMCs and will disappear.
 131  */
 132 struct wuie_channel_stop {
 133         struct wuie_hdr hdr;
 134         u8 attributes;
 135         u8 timestamp[3];
 136 } __attribute__((packed));
 137
 138 /**
 139  * WUSB IE: Keepalive (WUSB1.0[7.5.9])
 140  *
 141  * Ask device(s) to send keepalives.
 142  */
 143 struct wuie_keep_alive {
 144         struct wuie_hdr hdr;
 145         u8 bDeviceAddress[WUIE_ELT_MAX];
 146 } __attribute__((packed));
 147
 148 /**
 149  * WUSB IE: Reset device (WUSB1.0[7.5.11])
 150  *
 151  * Tell device to reset; in all truth, we can fit 4 CDIDs, but we only
 152  * use it for one at the time...
 153  *
 154  * In any case, this request is a wee bit silly: why don't they target
 155  * by address??
 156  */
 157 struct wuie_reset {
 158         struct wuie_hdr hdr;
 159         struct wusb_ckhdid CDID;
 160 } __attribute__((packed));
 161
 162 /**
 163  * WUSB IE: Disconnect device (WUSB1.0[7.5.11])
 164  *
 165  * Tell device to disconnect; we can fit 4 addresses, but we only use
 166  * it for one at the time...
 167  */
 168 struct wuie_disconnect {
 169         struct wuie_hdr hdr;
 170         u8 bDeviceAddress;
 171         u8 padding;
 172 } __attribute__((packed));
 173
 174 /**
 175  * WUSB IE: Host disconnect ([WUSB] section 7.5.5)
 176  *
 177  * Tells all connected devices to disconnect.
 178  */
 179 struct wuie_host_disconnect {
 180         struct wuie_hdr hdr;
 181 } __attribute__((packed));
 182
 183 /**
 184  * WUSB Device Notification header (WUSB1.0[7.6])
 185  */
 186 struct wusb_dn_hdr {
 187         u8 bType;
 188         u8 notifdata[];
 189 } __attribute__((packed));
 190
 191 /** Device Notification codes (WUSB1.0[Table 7-54]) */
 192 enum WUSB_DN {
 193         WUSB_DN_CONNECT = 0x01,
 194         WUSB_DN_DISCONNECT = 0x02,
 195         WUSB_DN_EPRDY = 0x03,
 196         WUSB_DN_MASAVAILCHANGED = 0x04,
 197         WUSB_DN_RWAKE = 0x05,
 198         WUSB_DN_SLEEP = 0x06,
 199         WUSB_DN_ALIVE = 0x07,
 200 };
 201
 202 /** WUSB Device Notification Connect */
 203 struct wusb_dn_connect {
 204         struct wusb_dn_hdr hdr;
 205         __le16 attributes;
 206         struct wusb_ckhdid CDID;
 207 } __attribute__((packed));
 208
 209 static inline int wusb_dn_connect_prev_dev_addr(const struct wusb_dn_connect *dn)
 210 {
 211         return le16_to_cpu(dn->attributes) & 0xff;
 212 }
 213
 214 static inline int wusb_dn_connect_new_connection(const struct wusb_dn_connect *dn)
 215 {
 216         return (le16_to_cpu(dn->attributes) >> 8) & 0x1;
 217 }
 218
 219 static inline int wusb_dn_connect_beacon_behavior(const struct wusb_dn_connect *dn)
 220 {
 221         return (le16_to_cpu(dn->attributes) >> 9) & 0x03;
 222 }
 223
 224 /** Device is alive (aka: pong) (WUSB1.0[7.6.7]) */
 225 struct wusb_dn_alive {
 226         struct wusb_dn_hdr hdr;
 227 } __attribute__((packed));
 228
 229 /** Device is disconnecting (WUSB1.0[7.6.2]) */
 230 struct wusb_dn_disconnect {
 231         struct wusb_dn_hdr hdr;
 232 } __attribute__((packed));
 233
 234 /* General constants */
 235 enum {
 236         WUSB_TRUST_TIMEOUT_MS = 4000,   /* [WUSB] section 4.15.1 */
 237 };
 238
 239 static inline size_t ckhdid_printf(char *pr_ckhdid, size_t size,
 240                                    const struct wusb_ckhdid *ckhdid)
 241 {
 242         return scnprintf(pr_ckhdid, size,
 243                          "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx "
 244                          "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx",
 245                          ckhdid->data[0],  ckhdid->data[1],
 246                          ckhdid->data[2],  ckhdid->data[3],
 247                          ckhdid->data[4],  ckhdid->data[5],
 248                          ckhdid->data[6],  ckhdid->data[7],
 249                          ckhdid->data[8],  ckhdid->data[9],
 250                          ckhdid->data[10], ckhdid->data[11],
 251                          ckhdid->data[12], ckhdid->data[13],
 252                          ckhdid->data[14], ckhdid->data[15]);
 253 }
 254
 255 /*
 256  * WUSB Crypto stuff (WUSB1.0[6])
 257  */
 258
 259 extern const char *wusb_et_name(u8);
 260
 261 /**
 262  * WUSB key index WUSB1.0[7.3.2.4], for usage when setting keys for
 263  * the host or the device.
 264  */
 265 static inline u8 wusb_key_index(int index, int type, int originator)
 266 {
 267         return (originator << 6) | (type << 4) | index;
 268 }
 269
 270 #define WUSB_KEY_INDEX_TYPE_PTK                 0 /* for HWA only */
 271 #define WUSB_KEY_INDEX_TYPE_ASSOC               1
 272 #define WUSB_KEY_INDEX_TYPE_GTK                 2
 273 #define WUSB_KEY_INDEX_ORIGINATOR_HOST          0
 274 #define WUSB_KEY_INDEX_ORIGINATOR_DEVICE        1
 275 /* bits 0-3 used for the key index. */
 276 #define WUSB_KEY_INDEX_MAX                      15
 277
 278 /* A CCM Nonce, defined in WUSB1.0[6.4.1] */
 279 struct aes_ccm_nonce {
 280         u8 sfn[6];              /* Little Endian */
 281         u8 tkid[3];             /* LE */
 282         struct uwb_dev_addr dest_addr;
 283         struct uwb_dev_addr src_addr;
 284 } __attribute__((packed));
 285
 286 /* A CCM operation label, defined on WUSB1.0[6.5.x] */
 287 struct aes_ccm_label {
 288         u8 data[14];
 289 } __attribute__((packed));
 290
 291 /*
 292  * Input to the key derivation sequence defined in
 293  * WUSB1.0[6.5.1]. Rest of the data is in the CCM Nonce passed to the
 294  * PRF function.
 295  */
 296 struct wusb_keydvt_in {
 297         u8 hnonce[16];
 298         u8 dnonce[16];
 299 } __attribute__((packed));
 300
 301 /*
 302  * Output from the key derivation sequence defined in
 303  * WUSB1.0[6.5.1].
 304  */
 305 struct wusb_keydvt_out {
 306         u8 kck[16];
 307         u8 ptk[16];
 308 } __attribute__((packed));
 309
 310 /* Pseudo Random Function WUSB1.0[6.5] */
 311 extern int wusb_crypto_init(void);
 312 extern void wusb_crypto_exit(void);
 313 extern ssize_t wusb_prf(void *out, size_t out_size,
 314                         const u8 key[16], const struct aes_ccm_nonce *_n,
 315                         const struct aes_ccm_label *a,
 316                         const void *b, size_t blen, size_t len);
 317
 318 static inline int wusb_prf_64(void *out, size_t out_size, const u8 key[16],
 319                               const struct aes_ccm_nonce *n,
 320                               const struct aes_ccm_label *a,
 321                               const void *b, size_t blen)
 322 {
 323         return wusb_prf(out, out_size, key, n, a, b, blen, 64);
 324 }
 325
 326 static inline int wusb_prf_128(void *out, size_t out_size, const u8 key[16],
 327                                const struct aes_ccm_nonce *n,
 328                                const struct aes_ccm_label *a,
 329                                const void *b, size_t blen)
 330 {
 331         return wusb_prf(out, out_size, key, n, a, b, blen, 128);
 332 }
 333
 334 static inline int wusb_prf_256(void *out, size_t out_size, const u8 key[16],
 335                                const struct aes_ccm_nonce *n,
 336                                const struct aes_ccm_label *a,
 337                                const void *b, size_t blen)
 338 {
 339         return wusb_prf(out, out_size, key, n, a, b, blen, 256);
 340 }
 341
 342 /* Key derivation WUSB1.0[6.5.1] */
 343 static inline int wusb_key_derive(struct wusb_keydvt_out *keydvt_out,
 344                                   const u8 key[16],
 345                                   const struct aes_ccm_nonce *n,
 346                                   const struct wusb_keydvt_in *keydvt_in)
 347 {
 348         const struct aes_ccm_label a = { .data = "Pair-wise keys" };
 349         return wusb_prf_256(keydvt_out, sizeof(*keydvt_out), key, n, &a,
 350                             keydvt_in, sizeof(*keydvt_in));
 351 }
 352
 353 /*
 354  * Out-of-band MIC Generation WUSB1.0[6.5.2]
 355  *
 356  * Compute the MIC over @key, @n and @hs and place it in @mic_out.
 357  *
 358  * @mic_out:  Where to place the 8 byte MIC tag
 359  * @key:      KCK from the derivation process
 360  * @n:        CCM nonce, n->sfn == 0, TKID as established in the
 361  *            process.
 362  * @hs:       Handshake struct for phase 2 of the 4-way.
 363  *            hs->bStatus and hs->bReserved are zero.
 364  *            hs->bMessageNumber is 2 (WUSB1.0[7.3.2.5.2]
 365  *            hs->dest_addr is the device's USB address padded with 0
 366  *            hs->src_addr is the hosts's UWB device address
 367  *            hs->mic is ignored (as we compute that value).
 368  */
 369 static inline int wusb_oob_mic(u8 mic_out[8], const u8 key[16],
 370                                const struct aes_ccm_nonce *n,
 371                                const struct usb_handshake *hs)
 372 {
 373         const struct aes_ccm_label a = { .data = "out-of-bandMIC" };
 374         return wusb_prf_64(mic_out, 8, key, n, &a,
 375                            hs, sizeof(*hs) - sizeof(hs->MIC));
 376 }
 377
 378 #endif /* #ifndef __WUSB_H__ */