include/linux/usb/wusb.h

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