/*
   * Wireless USB Standard Definitions
   * Event Size Tables
   *
   * Copyright (C) 2005-2006 Intel Corporation
   * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License version
   * 2 as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   * 02110-1301, USA.
   *
   *
   * FIXME: docs
   * FIXME: organize properly, group logically
   *
   * All the event structures are defined in uwb/spec.h, as they are
   * common to the WHCI and WUSB radio control interfaces.
   */
  
  #ifndef __WUSB_H__
  #define __WUSB_H__
  
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/uwb/spec.h>
  #include <linux/usb/ch9.h>
  #include <linux/param.h>
  
  /**
   * WUSB Information Element header
   *
   * I don't know why, they decided to make it different to the MBOA MAC
   * IE Header; beats me.
   */
  struct wuie_hdr {
  	u8 bLength;
  	u8 bIEIdentifier;
  } __attribute__((packed));
  
  enum {
  	WUIE_ID_WCTA = 0x80,
  	WUIE_ID_CONNECTACK,
  	WUIE_ID_HOST_INFO,
  	WUIE_ID_CHANGE_ANNOUNCE,
  	WUIE_ID_DEVICE_DISCONNECT,
  	WUIE_ID_HOST_DISCONNECT,
  	WUIE_ID_KEEP_ALIVE = 0x89,
  	WUIE_ID_ISOCH_DISCARD,
  	WUIE_ID_RESET_DEVICE,
  };
  
  /**
   * Maximum number of array elements in a WUSB IE.
   *
   * WUSB1.0[7.5 before table 7-38] says that in WUSB IEs that
   * are "arrays" have to limited to 4 elements. So we define it
   * like that to ease up and submit only the neeed size.
   */
  #define WUIE_ELT_MAX 4
  
  /**
   * Wrapper for the data that defines a CHID, a CDID or a CK
   *
   * WUSB defines that CHIDs, CDIDs and CKs are a 16 byte string of
   * data. In order to avoid confusion and enforce types, we wrap it.
   *
   * Make it packed, as we use it in some hw definitions.
   */
  struct wusb_ckhdid {
  	u8 data[16];
  } __attribute__((packed));
  
  static const struct wusb_ckhdid wusb_ckhdid_zero = { .data = { 0 } };
  
  #define WUSB_CKHDID_STRSIZE (3 * sizeof(struct wusb_ckhdid) + 1)
  
  /**
   * WUSB IE: Host Information (WUSB1.0[7.5.2])
   *
   * Used to provide information about the host to the Wireless USB
   * devices in range (CHID can be used as an ASCII string).
   */
  struct wuie_host_info {
  	struct wuie_hdr hdr;
  	__le16 attributes;
  	struct wusb_ckhdid CHID;
  } __attribute__((packed));
  
  /**
   * WUSB IE: Connect Ack (WUSB1.0[7.5.1])
   *
   * Used to acknowledge device connect requests. See note for
   * WUIE_ELT_MAX.
   */
  struct wuie_connect_ack {
  	struct wuie_hdr hdr;
  	struct {
  		struct wusb_ckhdid CDID;
  		u8 bDeviceAddress;	/* 0 means unused */
  		u8 bReserved;
  	} blk[WUIE_ELT_MAX];
  } __attribute__((packed));
  
  /**
   * WUSB IE Host Information Element, Connect Availability
   *
   * WUSB1.0[7.5.2], bmAttributes description
   */
  enum {
  	WUIE_HI_CAP_RECONNECT = 0,
  	WUIE_HI_CAP_LIMITED,
  	WUIE_HI_CAP_RESERVED,
  	WUIE_HI_CAP_ALL,
  };
  
  /**
   * WUSB IE: Channel Stop (WUSB1.0[7.5.8])
   *
   * Tells devices the host is going to stop sending MMCs and will disappear.
   */
  struct wuie_channel_stop {
  	struct wuie_hdr hdr;
  	u8 attributes;
  	u8 timestamp[3];
  } __attribute__((packed));
  
  /**
   * WUSB IE: Keepalive (WUSB1.0[7.5.9])
   *
   * Ask device(s) to send keepalives.
   */
  struct wuie_keep_alive {
  	struct wuie_hdr hdr;
  	u8 bDeviceAddress[WUIE_ELT_MAX];
  } __attribute__((packed));
  
  /**
   * WUSB IE: Reset device (WUSB1.0[7.5.11])
   *
   * Tell device to reset; in all truth, we can fit 4 CDIDs, but we only
   * use it for one at the time...
   *
   * In any case, this request is a wee bit silly: why don't they target
   * by address??
   */
  struct wuie_reset {
  	struct wuie_hdr hdr;
  	struct wusb_ckhdid CDID;
  } __attribute__((packed));
  
  /**
   * WUSB IE: Disconnect device (WUSB1.0[7.5.11])
   *
   * Tell device to disconnect; we can fit 4 addresses, but we only use
   * it for one at the time...
   */
  struct wuie_disconnect {
  	struct wuie_hdr hdr;
  	u8 bDeviceAddress;
  	u8 padding;
  } __attribute__((packed));
  
  /**
   * WUSB IE: Host disconnect ([WUSB] section 7.5.5)
   *
   * Tells all connected devices to disconnect.
   */
  struct wuie_host_disconnect {
  	struct wuie_hdr hdr;
  } __attribute__((packed));
  
  /**
   * WUSB Device Notification header (WUSB1.0[7.6])
   */
  struct wusb_dn_hdr {
  	u8 bType;
  	u8 notifdata[];
  } __attribute__((packed));
  
  /** Device Notification codes (WUSB1.0[Table 7-54]) */
  enum WUSB_DN {
  	WUSB_DN_CONNECT = 0x01,
  	WUSB_DN_DISCONNECT = 0x02,
  	WUSB_DN_EPRDY = 0x03,
  	WUSB_DN_MASAVAILCHANGED = 0x04,
  	WUSB_DN_RWAKE = 0x05,
  	WUSB_DN_SLEEP = 0x06,
  	WUSB_DN_ALIVE = 0x07,
  };
  
  /** WUSB Device Notification Connect */
  struct wusb_dn_connect {
  	struct wusb_dn_hdr hdr;
  	__le16 attributes;
  	struct wusb_ckhdid CDID;
  } __attribute__((packed));
  
  static inline int wusb_dn_connect_prev_dev_addr(const struct wusb_dn_connect *dn)
  {
  	return le16_to_cpu(dn->attributes) & 0xff;
  }
  
  static inline int wusb_dn_connect_new_connection(const struct wusb_dn_connect *dn)
  {
  	return (le16_to_cpu(dn->attributes) >> 8) & 0x1;
  }
  
  static inline int wusb_dn_connect_beacon_behavior(const struct wusb_dn_connect *dn)
  {
  	return (le16_to_cpu(dn->attributes) >> 9) & 0x03;
  }
  
  /** Device is alive (aka: pong) (WUSB1.0[7.6.7]) */
  struct wusb_dn_alive {
  	struct wusb_dn_hdr hdr;
  } __attribute__((packed));
  
  /** Device is disconnecting (WUSB1.0[7.6.2]) */
  struct wusb_dn_disconnect {
  	struct wusb_dn_hdr hdr;
  } __attribute__((packed));
  
  /* General constants */
  enum {
  	WUSB_TRUST_TIMEOUT_MS = 4000,	/* [WUSB] section 4.15.1 */
  };
  
  static inline size_t ckhdid_printf(char *pr_ckhdid, size_t size,
  				   const struct wusb_ckhdid *ckhdid)
  {
  	return scnprintf(pr_ckhdid, size,
  			 "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx "
  			 "%02hx %02hx %02hx %02hx %02hx %02hx %02hx %02hx",
  			 ckhdid->data[0],  ckhdid->data[1],
  			 ckhdid->data[2],  ckhdid->data[3],
  			 ckhdid->data[4],  ckhdid->data[5],
  			 ckhdid->data[6],  ckhdid->data[7],
  			 ckhdid->data[8],  ckhdid->data[9],
  			 ckhdid->data[10], ckhdid->data[11],
  			 ckhdid->data[12], ckhdid->data[13],
  			 ckhdid->data[14], ckhdid->data[15]);
  }
  
  /*
   * WUSB Crypto stuff (WUSB1.0[6])
   */
  
  extern const char *wusb_et_name(u8);
  
  /**
   * WUSB key index WUSB1.0[7.3.2.4], for usage when setting keys for
   * the host or the device.
   */
  static inline u8 wusb_key_index(int index, int type, int originator)
  {
  	return (originator << 6) | (type << 4) | index;
  }
  
  #define WUSB_KEY_INDEX_TYPE_PTK			0 /* for HWA only */
  #define WUSB_KEY_INDEX_TYPE_ASSOC		1
  #define WUSB_KEY_INDEX_TYPE_GTK			2
  #define WUSB_KEY_INDEX_ORIGINATOR_HOST		0
  #define WUSB_KEY_INDEX_ORIGINATOR_DEVICE	1
  /* bits 0-3 used for the key index. */
  #define WUSB_KEY_INDEX_MAX			15
  
  /* A CCM Nonce, defined in WUSB1.0[6.4.1] */
  struct aes_ccm_nonce {
  	u8 sfn[6];              /* Little Endian */
  	u8 tkid[3];             /* LE */
  	struct uwb_dev_addr dest_addr;
  	struct uwb_dev_addr src_addr;
  } __attribute__((packed));
  
  /* A CCM operation label, defined on WUSB1.0[6.5.x] */
  struct aes_ccm_label {
  	u8 data[14];
  } __attribute__((packed));
  
  /*
   * Input to the key derivation sequence defined in
   * WUSB1.0[6.5.1]. Rest of the data is in the CCM Nonce passed to the
   * PRF function.
   */
  struct wusb_keydvt_in {
  	u8 hnonce[16];
  	u8 dnonce[16];
  } __attribute__((packed));
  
  /*
   * Output from the key derivation sequence defined in
   * WUSB1.0[6.5.1].
   */
  struct wusb_keydvt_out {
  	u8 kck[16];
  	u8 ptk[16];
  } __attribute__((packed));
  
  /* Pseudo Random Function WUSB1.0[6.5] */
  extern int wusb_crypto_init(void);
  extern void wusb_crypto_exit(void);
  extern ssize_t wusb_prf(void *out, size_t out_size,
  			const u8 key[16], const struct aes_ccm_nonce *_n,
  			const struct aes_ccm_label *a,
  			const void *b, size_t blen, size_t len);
  
  static inline int wusb_prf_64(void *out, size_t out_size, const u8 key[16],
  			      const struct aes_ccm_nonce *n,
  			      const struct aes_ccm_label *a,
  			      const void *b, size_t blen)
  {
  	return wusb_prf(out, out_size, key, n, a, b, blen, 64);
  }
  
  static inline int wusb_prf_128(void *out, size_t out_size, const u8 key[16],
  			       const struct aes_ccm_nonce *n,
  			       const struct aes_ccm_label *a,
  			       const void *b, size_t blen)
  {
  	return wusb_prf(out, out_size, key, n, a, b, blen, 128);
  }
  
  static inline int wusb_prf_256(void *out, size_t out_size, const u8 key[16],
  			       const struct aes_ccm_nonce *n,
  			       const struct aes_ccm_label *a,
  			       const void *b, size_t blen)
  {
  	return wusb_prf(out, out_size, key, n, a, b, blen, 256);
  }
  
  /* Key derivation WUSB1.0[6.5.1] */
  static inline int wusb_key_derive(struct wusb_keydvt_out *keydvt_out,
  				  const u8 key[16],
  				  const struct aes_ccm_nonce *n,
  				  const struct wusb_keydvt_in *keydvt_in)
  {
  	const struct aes_ccm_label a = { .data = "Pair-wise keys" };
  	return wusb_prf_256(keydvt_out, sizeof(*keydvt_out), key, n, &a,
  			    keydvt_in, sizeof(*keydvt_in));
  }
  
  /*
   * Out-of-band MIC Generation WUSB1.0[6.5.2]
   *
   * Compute the MIC over @key, @n and @hs and place it in @mic_out.
   *
   * @mic_out:  Where to place the 8 byte MIC tag
   * @key:      KCK from the derivation process
   * @n:        CCM nonce, n->sfn == 0, TKID as established in the
   *            process.
   * @hs:       Handshake struct for phase 2 of the 4-way.
   *            hs->bStatus and hs->bReserved are zero.
   *            hs->bMessageNumber is 2 (WUSB1.0[7.3.2.5.2]
   *            hs->dest_addr is the device's USB address padded with 0
   *            hs->src_addr is the hosts's UWB device address
   *            hs->mic is ignored (as we compute that value).
   */
  static inline int wusb_oob_mic(u8 mic_out[8], const u8 key[16],
  			       const struct aes_ccm_nonce *n,
  			       const struct usb_handshake *hs)
  {
  	const struct aes_ccm_label a = { .data = "out-of-bandMIC" };
  	return wusb_prf_64(mic_out, 8, key, n, &a,
  			   hs, sizeof(*hs) - sizeof(hs->MIC));
  }
  
  #endif /* #ifndef __WUSB_H__ */