/*############################################################################
  # Copyright 2016 Intel Corporation
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  ############################################################################*/
#ifndef EPID_COMMON_TYPES_H_
#define EPID_COMMON_TYPES_H_

#include <limits.h>  // for CHAR_BIT

/*!
 * \file
 * \brief SDK data types.
*/

/// SDK data types.
/*!
  \defgroup EpidTypes types
  Defines serialized data types used by the SDK.

  Most of the types defined here are fixed size binary buffers of various sizes
  that are semantically mapped to the types of various inputs to the
  Intel(R) EPID APIs.

  For example ::GtElemStr is a 384 byte buffer that represents a serialized
  value that is compatible with a ::FfElement belonging to the ::FiniteField
  GT.

  \ingroup EpidCommon
  @{
*/

/// Recognized hash algorithms
typedef enum {
  /// Invalid
  kInvalidHashAlg = -1,
  /// SHA-256
  kSha256 = 0,
  /// SHA-384
  kSha384 = 1,
  /// SHA-512
  kSha512 = 2,
  /// SHA-512/256
  kSha512_256 = 3,
  /// Reserved for SHA3/256
  kSha3_256 = 4,
  /// Reserved for SHA3/384
  kSha3_384 = 5,
  /// Reserved for SHA3/512
  kSha3_512 = 6,
} HashAlg;

#pragma pack(1)
/// 8 bit octet string
typedef struct OctStr8 {
  unsigned char data[8 / CHAR_BIT];  ///< 8 bit data
} OctStr8;
/// 16 bit octet string
typedef struct OctStr16 {
  unsigned char data[16 / CHAR_BIT];  ///< 16 bit data
} OctStr16;
/// 32 bit octet string
typedef struct OctStr32 {
  unsigned char data[32 / CHAR_BIT];  ///< 32 bit data
} OctStr32;
/// 64 bit octet string
typedef struct OctStr64 {
  unsigned char data[64 / CHAR_BIT];  ///< 64 bit data
} OctStr64;
/// 128 bit octet string
typedef struct OctStr128 {
  unsigned char data[128 / CHAR_BIT];  ///< 128 bit data
} OctStr128;
/// 256 bit octet string
typedef struct OctStr256 {
  unsigned char data[256 / CHAR_BIT];  ///< 256 bit data
} OctStr256;
/// 512 bit octet string
typedef struct OctStr512 {
  unsigned char data[512 / CHAR_BIT];  ///< 512 bit data
} OctStr512;

/// Serialized BigNum
typedef struct BigNumStr {
  OctStr256 data;  ///< 256 bit octet string
} BigNumStr;
/// a number in [0, p-1]
typedef struct FpElemStr {
  OctStr256 data;  ///< 256 bit octet string
} FpElemStr;
/// a number in [0, q-1]
typedef struct FqElemStr {
  OctStr256 data;  ///< 256 bit octet string
} FqElemStr;

/// Serialized G1 element
typedef struct G1ElemStr {
  FqElemStr x;  ///< an integer between [0, q-1]
  FqElemStr y;  ///< an integer between [0, q-1]
} G1ElemStr;

/// Serialized G2 element
typedef struct G2ElemStr {
  FqElemStr x[2];  ///< an integer between [0, q-1]
  FqElemStr y[2];  ///< an integer between [0, q-1]
} G2ElemStr;

/// Serialized GT element
typedef struct GtElemStr {
  FqElemStr x[12];  ///< an integer between [0, q-1]
} GtElemStr;

/// Intel(R) EPID 2.0 Parameters.
/*!
 * Intel(R) EPID 2.0 parameters: (p, q, b, t, neg, beta, xi0, xi1,
 * g1, g2)
 */
typedef struct Epid2Params {
  BigNumStr p;      ///< a prime
  BigNumStr q;      ///< a prime
  FqElemStr b;      ///< an integer between [0, q-1]
  OctStr64 t;       ///< an integer
  OctStr8 neg;      ///< a boolean
  FqElemStr beta;   ///< an integer between [0, q-1]
  FqElemStr xi[2];  ///< array of integers between [0, q-1]
  G1ElemStr g1;     ///<  a generator (an element) of G1
  G2ElemStr g2;     ///<  a generator (an element) of G2
} Epid2Params;

/// group ID
typedef OctStr32 GroupId;
typedef OctStr32 RLver_t;
typedef OctStr32 RLCount;

/// Intel(R) EPID 2.0 group public key
/*!
 * Group public key: (gid, h1, h2, w)
 */
typedef struct GroupPubKey {
  GroupId gid;   ///< group ID
  G1ElemStr h1;  ///< an element in G1
  G1ElemStr h2;  ///< an element in G1
  G2ElemStr w;   ///< an element in G2
} GroupPubKey;

/// Intel(R) EPID 2.0 issuing private key
/*!
 * Issuing private key: (gid, gamma)
 */
typedef struct IPrivKey {
  GroupId gid;      ///< group ID
  FpElemStr gamma;  ///< an integer between [0, p-1]
} IPrivKey;

/// Intel(R) EPID 2.0 private key
/*!
 * Private key: (gid, A, x, f)
 */
typedef struct PrivKey {
  GroupId gid;  ///< group ID
  G1ElemStr A;  ///< an element in G1
  FpElemStr x;  ///< an integer between [0, p-1]
  FpElemStr f;  ///< an integer between [0, p-1]
} PrivKey;

/// 256 bit seed derived from fuse key
typedef OctStr256 Seed;

/// Compressed private key
/*!
 * Compressed Private key: (gid, A.x, seed)
 */
typedef struct CompressedPrivKey {
  GroupId gid;   ///< group ID
  FqElemStr ax;  ///< an integer between [0, p-1]
  Seed seed;     ///< 256 bit rekey seed
} CompressedPrivKey;

/// Membership credential
/*!
 * Membership credential: (gid, A, x)
 */
typedef struct MembershipCredential {
  GroupId gid;  ///< group ID
  G1ElemStr A;  ///< an element in G1
  FpElemStr x;  ///< an integer between [0, p-1]
} MembershipCredential;

/// 256 bit nonce chosen by issuer
typedef OctStr256 IssuerNonce;

/// Join request
/*!
 * Join request: (F, c, s)
 */
typedef struct JoinRequest {
  G1ElemStr F;  ///< an element in G1
  FpElemStr c;  ///< an integer between [0, p-1]
  FpElemStr s;  ///< an integer between [0, p-1]
} JoinRequest;

////////////////////////

/// Intel(R) EPID 2.0 basic signature.
/*!
 * Basic signature: (B, K, T, c, sx, sf, sa, sb)
 */
typedef struct BasicSignature {
  G1ElemStr B;   ///< an element in G1
  G1ElemStr K;   ///< an element in G1
  G1ElemStr T;   ///< an element in G1
  FpElemStr c;   ///< an integer between [0, p-1]
  FpElemStr sx;  ///< an integer between [0, p-1]
  FpElemStr sf;  ///< an integer between [0, p-1]
  FpElemStr sa;  ///< an integer between [0, p-1]
  FpElemStr sb;  ///< an integer between [0, p-1]
} BasicSignature;

///
/*!
 * \brief
 * non-revoked Proof.
 *
 * Non-revoked Proof: (T, c, smu, snu)
 */
typedef struct NrProof {
  G1ElemStr T;    ///< an element in G1
  FpElemStr c;    ///< an integer between [0, p-1]
  FpElemStr smu;  ///< an integer between [0, p-1]
  FpElemStr snu;  ///< an integer between [0, p-1]
} NrProof;

/// Intel(R) EPID 2.0 Signature
/*!
 * Signature: (sigma0, RLver, n2, sigma[0], ..., sigma[n2-1])
 */
typedef struct EpidSignature {
  BasicSignature sigma0;  ///< basic signature
  OctStr32 rl_ver;        ///< revocation list version number
  OctStr32 n2;            ///< number of entries in SigRL
  NrProof sigma[1];       ///< array of non-revoked proofs (flexible array)
} EpidSignature;

/// private-key based revocation list.
/*!
 * Private-key based revocation list PrivRL: (gid, RLver, n1, f[0],
 * ..., f[n1-1])
 */
typedef struct PrivRl {
  GroupId gid;       ///< group ID
  OctStr32 version;  ///< revocation list version number
  OctStr32 n1;       ///< number of entries in PrivRL
  FpElemStr f[1];    ///< integers between [1, p-1]  (flexible array)
} PrivRl;

/// entry in SigRL (B,K)
typedef struct SigRlEntry {
  G1ElemStr b;  ///< an element of G1
  G1ElemStr k;  ///< an element of G1
} SigRlEntry;

/// signature based revocation list
/*!
 * Signature based revocation list SigRL: (gid, RLver, n2, B[0],
 * K[0], ..., B[n2-1], K[n2-1])
 */
typedef struct SigRl {
  GroupId gid;       ///< group ID
  OctStr32 version;  ///< revocation list version number
  OctStr32 n2;       ///< number of entries in SigRL
  SigRlEntry bk[1];  ///< revoked  Bs and Ks (flexible array)
} SigRl;

/// group revocation list
/*!
 * Group revocation list GroupRL: (RLver, n3, gid[0], ...,
 * gid[n3-1])
 */
typedef struct GroupRl {
  OctStr32 version;  ///< revocation list version number
  OctStr32 n3;       ///< number of entries in GroupRL
  GroupId gid[1];    ///< revoked group IDs (flexible array)
} GroupRl;

/*! verifier revocation list
 * Verifier revocation list VerifierRL: (gid, B, RLver, n4, K[0],
 * ..., K[n4-1])
 */
typedef struct VerifierRl {
  GroupId gid;       ///< group ID
  G1ElemStr B;       ///< an element in G1
  OctStr32 version;  ///< revocation list version number
  OctStr32 n4;       ///< number of entries in VerifierRL
  G1ElemStr K[1];    ///< elements in G1 (flexible array)
} VerifierRl;

/// element to store seed values for later rekey
typedef G1ElemStr ReKeySeed;

/// Serialized Fq2 element
typedef struct Fq2ElemStr {
  FqElemStr a[2];  ///< polynomial coefficient
} Fq2ElemStr;

/// Serialized Fq2^3 element
typedef struct Fq6ElemStr {
  Fq2ElemStr a[3];  ///< polynomial coefficient
} Fq6ElemStr;

/// Serialized Fq2^3^2 element
typedef struct Fq12ElemStr {
  Fq6ElemStr a[2];  ///< polynomial coefficient
} Fq12ElemStr;

/// ECDSA Signature using NIST 256-bit curve secp256r1
typedef struct EcdsaSignature {
  OctStr256 x;  ///< 256-bit integer
  OctStr256 y;  ///< 256-bit integer
} EcdsaSignature;

/// ECDSA Public Key
typedef struct EcdsaPublicKey {
  OctStr256 x;  ///< 256-bit integer
  OctStr256 y;  ///< 256-bit integer
} EcdsaPublicKey;

/// ECDSA Private Key
typedef struct EcdsaPrivateKey {
  OctStr256 data;  ///< 256-bit integer
} EcdsaPrivateKey;
#pragma pack()

/*! @} */

#endif  // EPID_COMMON_TYPES_H_