path: root/include/hotstuff/crypto.h

#ifndef _HOTSTUFF_CRYPTO_H
#define _HOTSTUFF_CRYPTO_H

#include <openssl/rand.h>

#include "secp256k1.h"
#include "salticidae/crypto.h"
#include "hotstuff/type.h"

namespace hotstuff {

using salticidae::SHA256;

class PubKey: public Serializable, Cloneable {
    public:
    virtual ~PubKey() = default;
    virtual PubKey *clone() override = 0;
};

using pubkey_bt = BoxObj<PubKey>;

class PrivKey: public Serializable {
    public:
    virtual ~PrivKey() = default;
    virtual pubkey_bt get_pubkey() const = 0;
    virtual void from_rand() = 0;
};

using privkey_bt = BoxObj<PrivKey>;

class PartCert: public Serializable, public Cloneable {
    public:
    virtual ~PartCert() = default;
    virtual bool verify(const PubKey &pubkey) = 0;
    virtual const uint256_t &get_blk_hash() const = 0;
    virtual PartCert *clone() override = 0;
};

class ReplicaConfig;

class QuorumCert: public Serializable, public Cloneable {
    public:
    virtual ~QuorumCert() = default;
    virtual void add_part(ReplicaID replica, const PartCert &pc) = 0;
    virtual void compute() = 0;
    virtual bool verify(const ReplicaConfig &config) = 0;
    virtual const uint256_t &get_blk_hash() const = 0;
    virtual QuorumCert *clone() override = 0;
};

using part_cert_bt = BoxObj<PartCert>;
using quorum_cert_bt = BoxObj<QuorumCert>;

class PubKeyDummy: public PubKey {
    PubKeyDummy *clone() override { return new PubKeyDummy(*this); }
    void serialize(DataStream &) const override {}
    void unserialize(DataStream &) override {}
};

class PrivKeyDummy: public PrivKey {
    pubkey_bt get_pubkey() const override { return new PubKeyDummy(); }
    void serialize(DataStream &) const override {}
    void unserialize(DataStream &) override {}
    void from_rand() override {}
};

class PartCertDummy: public PartCert {
    uint256_t blk_hash;
    public:
    PartCertDummy() {}
    PartCertDummy(const uint256_t &blk_hash):
        blk_hash(blk_hash) {}

    void serialize(DataStream &s) const override {
        s << (uint32_t)0 << blk_hash;
    }

    void unserialize(DataStream &s) override {
        uint32_t tmp;
        s >> tmp >> blk_hash;
    }

    PartCert *clone() override {
        return new PartCertDummy(blk_hash);
    }

    bool verify(const PubKey &) override { return true; }

    const uint256_t &get_blk_hash() const override { return blk_hash; }
};

class QuorumCertDummy: public QuorumCert {
    uint256_t blk_hash;
    public:
    QuorumCertDummy() {}
    QuorumCertDummy(const ReplicaConfig &, const uint256_t &blk_hash):
        blk_hash(blk_hash) {}

    void serialize(DataStream &s) const override {
        s << (uint32_t)1 << blk_hash;
    }

    void unserialize(DataStream &s) override {
        uint32_t tmp;
        s >> tmp >> blk_hash;
    }

    QuorumCert *clone() override {
        return new QuorumCertDummy(*this);
    }

    void add_part(ReplicaID, const PartCert &) override {}
    void compute() override {}
    bool verify(const ReplicaConfig &) override { return true; }

    const uint256_t &get_blk_hash() const override { return blk_hash; }
};


class Secp256k1Context {
    secp256k1_context *ctx;
    friend class PubKeySecp256k1;
    friend class SigSecp256k1;
    public:
    Secp256k1Context(bool sign = false):
        ctx(secp256k1_context_create(
            sign ? SECP256K1_CONTEXT_SIGN :
                    SECP256K1_CONTEXT_VERIFY)) {}

    Secp256k1Context(const Secp256k1Context &) = delete;

    Secp256k1Context(Secp256k1Context &&other): ctx(other.ctx) {
        other.ctx = nullptr;
    }

    ~Secp256k1Context() {
        if (ctx) secp256k1_context_destroy(ctx);
    }
};

using secp256k1_context_t = RcObj<Secp256k1Context>;

extern secp256k1_context_t secp256k1_default_sign_ctx;
extern secp256k1_context_t secp256k1_default_verify_ctx;

class PrivKeySecp256k1;

class PubKeySecp256k1: public PubKey {
    static const auto _olen = 33;
    friend class SigSecp256k1;
    secp256k1_pubkey data;
    secp256k1_context_t ctx;

    public:
    PubKeySecp256k1(const secp256k1_context_t &ctx =
                            secp256k1_default_sign_ctx):
        PubKey(), ctx(ctx) {}
    
    PubKeySecp256k1(const bytearray_t &raw_bytes,
                    const secp256k1_context_t &ctx =
                            secp256k1_default_sign_ctx):
        PubKeySecp256k1(ctx) { from_bytes(raw_bytes); }

    inline PubKeySecp256k1(const PrivKeySecp256k1 &priv_key,
                            const secp256k1_context_t &ctx =
                                    secp256k1_default_sign_ctx);

    void serialize(DataStream &s) const override {
        static uint8_t output[_olen];
        size_t olen = _olen;
        (void)secp256k1_ec_pubkey_serialize(
                ctx->ctx, (unsigned char *)output,
                &olen, &data, SECP256K1_EC_COMPRESSED);
        s.put_data(output, output + _olen);
    }

    void unserialize(DataStream &s) override {
        static const auto _exc = std::invalid_argument("ill-formed public key");
        try {
            if (!secp256k1_ec_pubkey_parse(
                    ctx->ctx, &data, s.get_data_inplace(_olen), _olen))
                throw _exc;
        } catch (std::ios_base::failure &) {
            throw _exc;
        }
    }

    PubKeySecp256k1 *clone() override {
        return new PubKeySecp256k1(*this);
    }
};

class PrivKeySecp256k1: public PrivKey {
    static const auto nbytes = 32;
    friend class PubKeySecp256k1;
    friend class SigSecp256k1;
    uint8_t data[nbytes];
    secp256k1_context_t ctx;

    public:
    PrivKeySecp256k1(const secp256k1_context_t &ctx =
                            secp256k1_default_sign_ctx):
        PrivKey(), ctx(ctx) {}

    PrivKeySecp256k1(const bytearray_t &raw_bytes,
                     const secp256k1_context_t &ctx =
                            secp256k1_default_sign_ctx):
        PrivKeySecp256k1(ctx) { from_bytes(raw_bytes); }

    void serialize(DataStream &s) const override {
        s.put_data(data, data