/*
* (C) 2014,2015 Jack Lloyd
* (C) 2017 René Korthaus, Rohde & Schwarz Cybersecurity
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include "tests.h"

#include "test_rng.h"

#if defined(BOTAN_HAS_ECDSA)
   #include "test_pubkey.h"
   #include <botan/ecdsa.h>
   #include <botan/pk_algs.h>
#endif

namespace Botan_Tests {

namespace {

#if defined(BOTAN_HAS_ECDSA)

class ECDSA_Verification_Tests final : public PK_Signature_Verification_Test
   {
   public:
      ECDSA_Verification_Tests() : PK_Signature_Verification_Test(
            "ECDSA",
            "pubkey/ecdsa_verify.vec",
            "Group,Px,Py,Msg,Signature",
            "Valid") {}

      bool clear_between_callbacks() const override
         {
         return false;
         }

      std::unique_ptr<Botan::Public_Key> load_public_key(const VarMap& vars) override
         {
         const std::string group_id = vars.get_req_str("Group");
         const BigInt px = vars.get_req_bn("Px");
         const BigInt py = vars.get_req_bn("Py");
         Botan::EC_Group group(Botan::OID::from_string(group_id));

         const Botan::PointGFp public_point = group.point(px, py);

         return std::make_unique<Botan::ECDSA_PublicKey>(group, public_point);
         }

      std::string default_padding(const VarMap& /*unused*/) const override
         {
         return "Raw";
         }
   };

class ECDSA_Wycheproof_Verification_Tests final : public PK_Signature_Verification_Test
   {
   public:
      ECDSA_Wycheproof_Verification_Tests() : PK_Signature_Verification_Test(
            "ECDSA",
            "pubkey/ecdsa_wycheproof.vec",
            "Group,Px,Py,Hash,Msg,Signature",
            "Valid") {}

      bool clear_between_callbacks() const override
         {
         return false;
         }

      Botan::Signature_Format sig_format() const override
         {
         return Botan::DER_SEQUENCE;
         }

      bool test_random_invalid_sigs() const override { return false; }

      std::unique_ptr<Botan::Public_Key> load_public_key(const VarMap& vars) override
         {
         const std::string group_id = vars.get_req_str("Group");
         const BigInt px = vars.get_req_bn("Px");
         const BigInt py = vars.get_req_bn("Py");
         Botan::EC_Group group(Botan::OID::from_string(group_id));

         const Botan::PointGFp public_point = group.point(px, py);

         return std::make_unique<Botan::ECDSA_PublicKey>(group, public_point);
         }

      std::string default_padding(const VarMap& vars) const override
         {
         return "EMSA1(" + vars.get_req_str("Hash") + ")";
         }
   };

class ECDSA_Signature_KAT_Tests final : public PK_Signature_Generation_Test
   {
   public:
      ECDSA_Signature_KAT_Tests() : PK_Signature_Generation_Test(
            "ECDSA",
#if defined(BOTAN_HAS_RFC6979_GENERATOR)
            "pubkey/ecdsa_rfc6979.vec",
            "Group,X,Hash,Msg,Signature") {}
#else
            "pubkey/ecdsa_prob.vec",
            "Group,X,Hash,Msg,Nonce,Signature") {}
#endif

      bool clear_between_callbacks() const override
         {
         return false;
         }

      std::unique_ptr<Botan::Private_Key> load_private_key(const VarMap& vars) override
         {
         const std::string group_id = vars.get_req_str("Group");
         const BigInt x = vars.get_req_bn("X");
         Botan::EC_Group group(Botan::OID::from_string(group_id));

         return std::make_unique<Botan::ECDSA_PrivateKey>(Test::rng(), group, x);
         }

      std::string default_padding(const VarMap& vars) const override
         {
         std::string hash = vars.get_req_str("Hash");
         if(hash.substr(0,3) == "Raw")
            return hash;
         return "EMSA1(" + hash + ")";
         }

#if !defined(BOTAN_HAS_RFC6979_GENERATOR)
      std::unique_ptr<Botan::RandomNumberGenerator> test_rng(const std::vector<uint8_t>& nonce) const override
         {
         // probabilistic ecdsa signature generation extracts more random than just the nonce,
         // but the nonce is extracted first
         return std::make_unique<Fixed_Output_Position_RNG>(nonce, 1);
         }
#endif
   };

class ECDSA_Sign_Verify_DER_Test final : public PK_Sign_Verify_DER_Test
   {
   public:
      ECDSA_Sign_Verify_DER_Test() :
         PK_Sign_Verify_DER_Test("ECDSA", "EMSA1(SHA-512)") {}

      std::unique_ptr<Botan::Private_Key> key() const override
         {
         return Botan::create_private_key( "ECDSA",  Test::rng(), "secp256r1" );
         }
   };

class ECDSA_Keygen_Tests final : public PK_Key_Generation_Test
   {
   public:
      std::vector<std::string> keygen_params() const override
         {
         return { "secp256r1", "secp384r1", "secp521r1", "frp256v1" };
         }
      std::string algo_name() const override
         {
         return "ECDSA";
         }
   };

#if defined(BOTAN_HAS_EMSA_RAW)

class ECDSA_Key_Recovery_Tests final : public Text_Based_Test
   {
   public:
      ECDSA_Key_Recovery_Tests() :
         Text_Based_Test("pubkey/ecdsa_key_recovery.vec", "Group,Msg,R,S,V,PubkeyX,PubkeyY") {}

      Test::Result run_one_test(const std::string& /*header*/, const VarMap& vars) override
         {
         Test::Result result("ECDSA key recovery");

         const std::string group_id = vars.get_req_str("Group");
         Botan::EC_Group group(group_id);

         const BigInt R = vars.get_req_bn("R");
         const BigInt S = vars.get_req_bn("S");
         const uint8_t V = vars.get_req_u8("V");
         const std::vector<uint8_t> msg = vars.get_req_bin("Msg");
         const BigInt pubkey_x = vars.get_req_bn("PubkeyX");
         const BigInt pubkey_y = vars.get_req_bn("PubkeyY");

         try
            {
            Botan::ECDSA_PublicKey pubkey(group, msg, R, S, V);
            result.test_eq("Pubkey X coordinate", pubkey.public_point().get_affine_x(), pubkey_x);
            result.test_eq("Pubkey Y coordinate", pubkey.public_point().get_affine_y(), pubkey_y);

            const uint8_t computed_V = pubkey.recovery_param(msg, R, S);
            result.test_eq("Recovery param is correct", static_cast<size_t>(computed_V), static_cast<size_t>(V));

            Botan::PK_Verifier verifier(pubkey, "Raw");

            auto sig = Botan::BigInt::encode_fixed_length_int_pair(R, S, group.get_order_bytes());

            result.confirm("Signature verifies", verifier.verify_message(msg, sig));
            }
         catch(Botan::Exception& e)
            {
            result.test_failure("Failed to recover ECDSA public key", e.what());
            }

         return result;
         }
   };

BOTAN_REGISTER_TEST("pubkey", "ecdsa_key_recovery", ECDSA_Key_Recovery_Tests);

#endif

class ECDSA_Invalid_Key_Tests final : public Text_Based_Test
   {
   public:
      ECDSA_Invalid_Key_Tests() :
         Text_Based_Test("pubkey/ecdsa_invalid.vec", "Group,InvalidKeyX,InvalidKeyY") {}

      bool clear_between_callbacks() const override
         {
         return false;
         }

      Test::Result run_one_test(const std::string& /*header*/, const VarMap& vars) override
         {
         Test::Result result("ECDSA invalid keys");

         const std::string group_id = vars.get_req_str("Group");
         Botan::EC_Group group(Botan::OID::from_string(group_id));
         const Botan::BigInt x = vars.get_req_bn("InvalidKeyX");
         const Botan::BigInt y = vars.get_req_bn("InvalidKeyY");

         std::unique_ptr<Botan::PointGFp> public_point;

         try
            {
            public_point.reset(new Botan::PointGFp(group.point(x, y)));
            }
         catch(Botan::Invalid_Argument&)
            {
            // PointGFp() performs a range check on x, y in [0, p−1],
            // which is also part of the EC public key checks, e.g.,
            // in NIST SP800-56A rev2, sec. 5.6.2.3.2
            result.test_success("public key fails check");
            return result;
            }

         auto key = std::make_unique<Botan::ECDSA_PublicKey>(group, *public_point);
         result.test_eq("public key fails check", key->check_key(Test::rng(), false), false);
         return result;
         }
   };

BOTAN_REGISTER_TEST("pubkey", "ecdsa_verify", ECDSA_Verification_Tests);
BOTAN_REGISTER_TEST("pubkey", "ecdsa_verify_wycheproof", ECDSA_Wycheproof_Verification_Tests);
BOTAN_REGISTER_TEST("pubkey", "ecdsa_sign", ECDSA_Signature_KAT_Tests);
BOTAN_REGISTER_TEST("pubkey", "ecdsa_sign_verify_der", ECDSA_Sign_Verify_DER_Test);
BOTAN_REGISTER_TEST("pubkey", "ecdsa_keygen", ECDSA_Keygen_Tests);
BOTAN_REGISTER_TEST("pubkey", "ecdsa_invalid", ECDSA_Invalid_Key_Tests);

#endif

}

}