Exemplo n.º 1
0
// This example demonstrates signing a message with a secp256k1 private key that
// is first parsed form raw bytes and serializing the generated signature.
func Example_signMessage() {
	// Decode a hex-encoded private key.
	pkBytes, err := hex.DecodeString("22a47fa09a223f2aa079edf85a7c2d4f87" +
		"20ee63e502ee2869afab7de234b80c")
	if err != nil {
		fmt.Println(err)
		return
	}
	privKey, pubKey := btcec.PrivKeyFromBytes(btcec.S256(), pkBytes)

	// Sign a message using the private key.
	message := "test message"
	messageHash := wire.DoubleSha256([]byte(message))
	signature, err := privKey.Sign(messageHash)
	if err != nil {
		fmt.Println(err)
		return
	}

	// Serialize and display the signature.
	fmt.Printf("Serialized Signature: %x\n", signature.Serialize())

	// Verify the signature for the message using the public key.
	verified := signature.Verify(messageHash, pubKey)
	fmt.Printf("Signature Verified? %v\n", verified)

	// Output:
	// Serialized Signature: 304402201008e236fa8cd0f25df4482dddbb622e8a8b26ef0ba731719458de3ccd93805b022032f8ebe514ba5f672466eba334639282616bb3c2f0ab09998037513d1f9e3d6d
	// Signature Verified? true
}
Exemplo n.º 2
0
// This example demonstrates decrypting a message using a private key that is
// first parsed from raw bytes.
func Example_decryptMessage() {
	// Decode the hex-encoded private key.
	pkBytes, err := hex.DecodeString("a11b0a4e1a132305652ee7a8eb7848f6ad" +
		"5ea381e3ce20a2c086a2e388230811")
	if err != nil {
		fmt.Println(err)
		return
	}

	privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), pkBytes)

	ciphertext, err := hex.DecodeString("35f644fbfb208bc71e57684c3c8b437402ca" +
		"002047a2f1b38aa1a8f1d5121778378414f708fe13ebf7b4a7bb74407288c1958969" +
		"00207cf4ac6057406e40f79961c973309a892732ae7a74ee96cd89823913b8b8d650" +
		"a44166dc61ea1c419d47077b748a9c06b8d57af72deb2819d98a9d503efc59fc8307" +
		"d14174f8b83354fac3ff56075162")

	// Try decrypting the message.
	plaintext, err := btcec.Decrypt(privKey, ciphertext)
	if err != nil {
		fmt.Println(err)
		return
	}

	fmt.Println(string(plaintext))

	// Output:
	// test message
}
Exemplo n.º 3
0
func TestPrivKeys(t *testing.T) {
	tests := []struct {
		name string
		key  []byte
	}{
		{
			name: "check curve",
			key: []byte{
				0xea, 0xf0, 0x2c, 0xa3, 0x48, 0xc5, 0x24, 0xe6,
				0x39, 0x26, 0x55, 0xba, 0x4d, 0x29, 0x60, 0x3c,
				0xd1, 0xa7, 0x34, 0x7d, 0x9d, 0x65, 0xcf, 0xe9,
				0x3c, 0xe1, 0xeb, 0xff, 0xdc, 0xa2, 0x26, 0x94,
			},
		},
	}

	for _, test := range tests {
		priv, pub := btcec.PrivKeyFromBytes(btcec.S256(), test.key)

		_, err := btcec.ParsePubKey(
			pub.SerializeUncompressed(), btcec.S256())
		if err != nil {
			t.Errorf("%s privkey: %v", test.name, err)
			continue
		}

		hash := []byte{0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9}
		sig, err := priv.Sign(hash)
		if err != nil {
			t.Errorf("%s could not sign: %v", test.name, err)
			continue
		}

		if !sig.Verify(hash, pub) {
			t.Errorf("%s could not verify: %v", test.name, err)
			continue
		}

		serializedKey := priv.Serialize()
		if !bytes.Equal(serializedKey, test.key) {
			t.Errorf("%s unexpected serialized bytes - got: %x, "+
				"want: %x", test.name, serializedKey, test.key)
		}
	}
}
Exemplo n.º 4
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// This example demonstrates encrypting a message for a public key that is first
// parsed from raw bytes, then decrypting it using the corresponding private key.
func Example_encryptMessage() {
	// Decode the hex-encoded pubkey of the recipient.
	pubKeyBytes, err := hex.DecodeString("04115c42e757b2efb7671c578530ec191a1" +
		"359381e6a71127a9d37c486fd30dae57e76dc58f693bd7e7010358ce6b165e483a29" +
		"21010db67ac11b1b51b651953d2") // uncompressed pubkey
	if err != nil {
		fmt.Println(err)
		return
	}
	pubKey, err := btcec.ParsePubKey(pubKeyBytes, btcec.S256())
	if err != nil {
		fmt.Println(err)
		return
	}

	// Encrypt a message decryptable by the private key corresponding to pubKey
	message := "test message"
	ciphertext, err := btcec.Encrypt(pubKey, []byte(message))
	if err != nil {
		fmt.Println(err)
		return
	}

	// Decode the hex-encoded private key.
	pkBytes, err := hex.DecodeString("a11b0a4e1a132305652ee7a8eb7848f6ad" +
		"5ea381e3ce20a2c086a2e388230811")
	if err != nil {
		fmt.Println(err)
		return
	}
	// note that we already have corresponding pubKey
	privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), pkBytes)

	// Try decrypting and verify if it's the same message.
	plaintext, err := btcec.Decrypt(privKey, ciphertext)
	if err != nil {
		fmt.Println(err)
		return
	}

	fmt.Println(string(plaintext))

	// Output:
	// test message
}
Exemplo n.º 5
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// Test 2: Byte compatibility with Pyelliptic
func TestCiphering(t *testing.T) {
	pb, _ := hex.DecodeString("fe38240982f313ae5afb3e904fb8215fb11af1200592b" +
		"fca26c96c4738e4bf8f")
	privkey, _ := btcec.PrivKeyFromBytes(btcec.S256(), pb)

	in := []byte("This is just a test.")
	out, _ := hex.DecodeString("b0d66e5adaa5ed4e2f0ca68e17b8f2fc02ca002009e3" +
		"3487e7fa4ab505cf34d98f131be7bd258391588ca7804acb30251e71a04e0020ecf" +
		"df0f84608f8add82d7353af780fbb28868c713b7813eb4d4e61f7b75d7534dd9856" +
		"9b0ba77cf14348fcff80fee10e11981f1b4be372d93923e9178972f69937ec850ed" +
		"6c3f11ff572ddd5b2bedf9f9c0b327c54da02a28fcdce1f8369ffec")

	dec, err := btcec.Decrypt(privkey, out)
	if err != nil {
		t.Fatal("failed to decrypt:", err)
	}

	if !bytes.Equal(in, dec) {
		t.Error("decrypted data doesn't match original")
	}
}
Exemplo n.º 6
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func TestRFC6979(t *testing.T) {
	// Test vectors matching Trezor and CoreBitcoin implementations.
	// - https://github.com/trezor/trezor-crypto/blob/9fea8f8ab377dc514e40c6fd1f7c89a74c1d8dc6/tests.c#L432-L453
	// - https://github.com/oleganza/CoreBitcoin/blob/e93dd71207861b5bf044415db5fa72405e7d8fbc/CoreBitcoin/BTCKey%2BTests.m#L23-L49
	tests := []struct {
		key       string
		msg       string
		nonce     string
		signature string
	}{
		{
			"cca9fbcc1b41e5a95d369eaa6ddcff73b61a4efaa279cfc6567e8daa39cbaf50",
			"sample",
			"2df40ca70e639d89528a6b670d9d48d9165fdc0febc0974056bdce192b8e16a3",
			"3045022100af340daf02cc15c8d5d08d7735dfe6b98a474ed373bdb5fbecf7571be52b384202205009fb27f37034a9b24b707b7c6b79ca23ddef9e25f7282e8a797efe53a8f124",
		},
		{
			// This signature hits the case when S is higher than halforder.
			// If S is not canonicalized (lowered by halforder), this test will fail.
			"0000000000000000000000000000000000000000000000000000000000000001",
			"Satoshi Nakamoto",
			"8f8a276c19f4149656b280621e358cce24f5f52542772691ee69063b74f15d15",
			"3045022100934b1ea10a4b3c1757e2b0c017d0b6143ce3c9a7e6a4a49860d7a6ab210ee3d802202442ce9d2b916064108014783e923ec36b49743e2ffa1c4496f01a512aafd9e5",
		},
		{
			"fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364140",
			"Satoshi Nakamoto",
			"33a19b60e25fb6f4435af53a3d42d493644827367e6453928554f43e49aa6f90",
			"3045022100fd567d121db66e382991534ada77a6bd3106f0a1098c231e47993447cd6af2d002206b39cd0eb1bc8603e159ef5c20a5c8ad685a45b06ce9bebed3f153d10d93bed5",
		},
		{
			"f8b8af8ce3c7cca5e300d33939540c10d45ce001b8f252bfbc57ba0342904181",
			"Alan Turing",
			"525a82b70e67874398067543fd84c83d30c175fdc45fdeee082fe13b1d7cfdf1",
			"304402207063ae83e7f62bbb171798131b4a0564b956930092b33b07b395615d9ec7e15c022058dfcc1e00a35e1572f366ffe34ba0fc47db1e7189759b9fb233c5b05ab388ea",
		},
		{
			"0000000000000000000000000000000000000000000000000000000000000001",
			"All those moments will be lost in time, like tears in rain. Time to die...",
			"38aa22d72376b4dbc472e06c3ba403ee0a394da63fc58d88686c611aba98d6b3",
			"30450221008600dbd41e348fe5c9465ab92d23e3db8b98b873beecd930736488696438cb6b0220547fe64427496db33bf66019dacbf0039c04199abb0122918601db38a72cfc21",
		},
		{
			"e91671c46231f833a6406ccbea0e3e392c76c167bac1cb013f6f1013980455c2",
			"There is a computer disease that anybody who works with computers knows about. It's a very serious disease and it interferes completely with the work. The trouble with computers is that you 'play' with them!",
			"1f4b84c23a86a221d233f2521be018d9318639d5b8bbd6374a8a59232d16ad3d",
			"3045022100b552edd27580141f3b2a5463048cb7cd3e047b97c9f98076c32dbdf85a68718b0220279fa72dd19bfae05577e06c7c0c1900c371fcd5893f7e1d56a37d30174671f6",
		},
	}

	for i, test := range tests {
		privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), decodeHex(test.key))
		hash := fastsha256.Sum256([]byte(test.msg))

		// Ensure deterministically generated nonce is the expected value.
		gotNonce := btcec.TstNonceRFC6979(privKey.D, hash[:]).Bytes()
		wantNonce := decodeHex(test.nonce)
		if !bytes.Equal(gotNonce, wantNonce) {
			t.Errorf("NonceRFC6979 #%d (%s): Nonce is incorrect: "+
				"%x (expected %x)", i, test.msg, gotNonce,
				wantNonce)
			continue
		}

		// Ensure deterministically generated signature is the expected value.
		gotSig, err := privKey.Sign(hash[:])
		if err != nil {
			t.Errorf("Sign #%d (%s): unexpected error: %v", i,
				test.msg, err)
			continue
		}
		gotSigBytes := gotSig.Serialize()
		wantSigBytes := decodeHex(test.signature)
		if !bytes.Equal(gotSigBytes, wantSigBytes) {
			t.Errorf("Sign #%d (%s): mismatched signature: %x "+
				"(expected %x)", i, test.msg, gotSigBytes,
				wantSigBytes)
			continue
		}
	}
}
Exemplo n.º 7
0
// Test the sigscript generation for valid and invalid inputs, all
// hashTypes, and with and without compression.  This test creates
// sigscripts to spend fake coinbase inputs, as sigscripts cannot be
// created for the MsgTxs in txTests, since they come from the blockchain
// and we don't have the private keys.
func TestSignatureScript(t *testing.T) {
	t.Parallel()

	privKey, _ := btcec.PrivKeyFromBytes(btcec.S256(), privKeyD)

nexttest:
	for i := range sigScriptTests {
		tx := wire.NewMsgTx()

		output := wire.NewTxOut(500, []byte{txscript.OP_RETURN})
		tx.AddTxOut(output)

		for _ = range sigScriptTests[i].inputs {
			txin := wire.NewTxIn(coinbaseOutPoint, nil)
			tx.AddTxIn(txin)
		}

		var script []byte
		var err error
		for j := range tx.TxIn {
			var idx int
			if sigScriptTests[i].inputs[j].indexOutOfRange {
				t.Errorf("at test %v", sigScriptTests[i].name)
				idx = len(sigScriptTests[i].inputs)
			} else {
				idx = j
			}
			script, err = txscript.SignatureScript(tx, idx,
				sigScriptTests[i].inputs[j].txout.PkScript,
				sigScriptTests[i].hashType, privKey,
				sigScriptTests[i].compress)

			if (err == nil) != sigScriptTests[i].inputs[j].sigscriptGenerates {
				if err == nil {
					t.Errorf("passed test '%v' incorrectly",
						sigScriptTests[i].name)
				} else {
					t.Errorf("failed test '%v': %v",
						sigScriptTests[i].name, err)
				}
				continue nexttest
			}
			if !sigScriptTests[i].inputs[j].sigscriptGenerates {
				// done with this test
				continue nexttest
			}

			tx.TxIn[j].SignatureScript = script
		}

		// If testing using a correct sigscript but for an incorrect
		// index, use last input script for first input.  Requires > 0
		// inputs for test.
		if sigScriptTests[i].scriptAtWrongIndex {
			tx.TxIn[0].SignatureScript = script
			sigScriptTests[i].inputs[0].inputValidates = false
		}

		// Validate tx input scripts
		scriptFlags := txscript.ScriptBip16 | txscript.ScriptVerifyDERSignatures
		for j := range tx.TxIn {
			vm, err := txscript.NewEngine(sigScriptTests[i].
				inputs[j].txout.PkScript, tx, j, scriptFlags, nil)
			if err != nil {
				t.Errorf("cannot create script vm for test %v: %v",
					sigScriptTests[i].name, err)
				continue nexttest
			}
			err = vm.Execute()
			if (err == nil) != sigScriptTests[i].inputs[j].inputValidates {
				if err == nil {
					t.Errorf("passed test '%v' validation incorrectly: %v",
						sigScriptTests[i].name, err)
				} else {
					t.Errorf("failed test '%v' validation: %v",
						sigScriptTests[i].name, err)
				}
				continue nexttest
			}
		}
	}
}
Exemplo n.º 8
0
// This example demonstrates manually creating and signing a redeem transaction.
func ExampleSignTxOutput() {
	// Ordinarily the private key would come from whatever storage mechanism
	// is being used, but for this example just hard code it.
	privKeyBytes, err := hex.DecodeString("22a47fa09a223f2aa079edf85a7c2" +
		"d4f8720ee63e502ee2869afab7de234b80c")
	if err != nil {
		fmt.Println(err)
		return
	}
	privKey, pubKey := btcec.PrivKeyFromBytes(btcec.S256(), privKeyBytes)
	pubKeyHash := btcutil.Hash160(pubKey.SerializeCompressed())
	addr, err := btcutil.NewAddressPubKeyHash(pubKeyHash,
		&chaincfg.MainNetParams)
	if err != nil {
		fmt.Println(err)
		return
	}

	// For this example, create a fake transaction that represents what
	// would ordinarily be the real transaction that is being spent.  It
	// contains a single output that pays to address in the amount of 1 BTC.
	originTx := wire.NewMsgTx()
	prevOut := wire.NewOutPoint(&wire.ShaHash{}, ^uint32(0))
	txIn := wire.NewTxIn(prevOut, []byte{txscript.OP_0, txscript.OP_0})
	originTx.AddTxIn(txIn)
	pkScript, err := txscript.PayToAddrScript(addr)
	if err != nil {
		fmt.Println(err)
		return
	}
	txOut := wire.NewTxOut(100000000, pkScript)
	originTx.AddTxOut(txOut)
	originTxHash := originTx.TxSha()

	// Create the transaction to redeem the fake transaction.
	redeemTx := wire.NewMsgTx()

	// Add the input(s) the redeeming transaction will spend.  There is no
	// signature script at this point since it hasn't been created or signed
	// yet, hence nil is provided for it.
	prevOut = wire.NewOutPoint(&originTxHash, 0)
	txIn = wire.NewTxIn(prevOut, nil)
	redeemTx.AddTxIn(txIn)

	// Ordinarily this would contain that actual destination of the funds,
	// but for this example don't bother.
	txOut = wire.NewTxOut(0, nil)
	redeemTx.AddTxOut(txOut)

	// Sign the redeeming transaction.
	lookupKey := func(a btcutil.Address) (*btcec.PrivateKey, bool, error) {
		// Ordinarily this function would involve looking up the private
		// key for the provided address, but since the only thing being
		// signed in this example uses the address associated with the
		// private key from above, simply return it with the compressed
		// flag set since the address is using the associated compressed
		// public key.
		//
		// NOTE: If you want to prove the code is actually signing the
		// transaction properly, uncomment the following line which
		// intentionally returns an invalid key to sign with, which in
		// turn will result in a failure during the script execution
		// when verifying the signature.
		//
		// privKey.D.SetInt64(12345)
		//
		return privKey, true, nil
	}
	// Notice that the script database parameter is nil here since it isn't
	// used.  It must be specified when pay-to-script-hash transactions are
	// being signed.
	sigScript, err := txscript.SignTxOutput(&chaincfg.MainNetParams,
		redeemTx, 0, originTx.TxOut[0].PkScript, txscript.SigHashAll,
		txscript.KeyClosure(lookupKey), nil, nil)
	if err != nil {
		fmt.Println(err)
		return
	}
	redeemTx.TxIn[0].SignatureScript = sigScript

	// Prove that the transaction has been validly signed by executing the
	// script pair.
	flags := txscript.ScriptBip16 | txscript.ScriptVerifyDERSignatures |
		txscript.ScriptStrictMultiSig |
		txscript.ScriptDiscourageUpgradableNops
	vm, err := txscript.NewEngine(originTx.TxOut[0].PkScript, redeemTx, 0,
		flags, nil)
	if err != nil {
		fmt.Println(err)
		return
	}
	if err := vm.Execute(); err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println("Transaction successfully signed")

	// Output:
	// Transaction successfully signed
}