Merge pull request #6 from Web3Auth/session-management

Session management

Author: chaitanyapotti

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "Plugins/Web3AuthSDK/Source/Web3AuthSDK/Public/secp256k1"]
+	path = Plugins/Web3AuthSDK/Source/Web3AuthSDK/Public/secp256k1
+	url = https://github.com/bitcoin-core/secp256k1

Plugins/Web3AuthSDK/Source/Web3AuthSDK/Private/ECCrypto.cpp

@@ -0,0 +1,230 @@
+#include "ECCrypto.h"
+#include <string>
+#include <vector>
+#include <Web3Auth.h>
+
+#pragma comment(lib, "crypt32.lib")
+#pragma comment(lib, "WS2_32.lib")
+
+
+unsigned char* toByteArray(const std::string& s) {
+	size_t len = s.length() / 2;
+	unsigned char* data = new unsigned char[len];
+
+	for (size_t i = 0; i < len * 2; i += 2) {
+		int hi = std::stoi(s.substr(i, 1), nullptr, 16);
+		int lo = std::stoi(s.substr(i + 1, 1), nullptr, 16);
+		data[i / 2] = (unsigned char)((hi << 4) + lo);
+	}
+
+	return data;
+
+}
+
+char* FStringToCharArray(const FString& InString) {
+	char* CharArray = new char[InString.Len() + 1];    
+	
+	strcpy(CharArray, TCHAR_TO_ANSI(*InString));    
+	return CharArray;
+}
+
+UECCrypto::UECCrypto() {
+}
+
+FString UECCrypto::decrypt(FString data, FString privateKeyHex, FString ephemPublicKeyHex, FString encryptionIvHex)
+{
+	// Convert to bytes array
+	const char* priv_hex = FStringToCharArray(privateKeyHex);
+	const char* pub_hex  = FStringToCharArray(ephemPublicKeyHex);
+
+	// Decode IV key
+	const unsigned char* iv = toByteArray(FStringToCharArray(encryptionIvHex));
+
+	// Decode cipher text
+	const unsigned char* src = toByteArray(FStringToCharArray(data));
+	int srclen = data.Len() / 2;
+
+	// Convert to BIGNUM
+	BIGNUM* priv_bn = BN_new();
+	BIGNUM* pub_bn = BN_new();
+	BN_hex2bn(&priv_bn, priv_hex);
+	BN_hex2bn(&pub_bn, pub_hex);
+
+	// Create EC_KEY objects from the BIGNUMs
+	EC_KEY* priv_key = EC_KEY_new_by_curve_name(NID_secp256k1);
+	EC_KEY* pub_key = EC_KEY_new_by_curve_name(NID_secp256k1);
+	EC_KEY_set_private_key(priv_key, priv_bn);
+	EC_KEY_set_public_key(pub_key, EC_POINT_bn2point(EC_KEY_get0_group(pub_key), pub_bn, NULL, NULL));
+
+	// Create the shared secret
+	unsigned char* secret = new unsigned char[32];
+	int secret_len = ECDH_compute_key(secret, EVP_MAX_KEY_LENGTH, EC_KEY_get0_public_key(pub_key), priv_key, NULL);
+
+	// Calculate SHA-512 hash of secret
+	unsigned char hash[SHA512_DIGEST_LENGTH];
+	SHA512(secret, 32, hash);
+
+	// Copy first 32 bytes of the hash into a new buffer
+	unsigned char key[32];
+	memcpy(key, hash, 32);
+
+	// Create a new encryption context for AES-256 CBC mode with the key and IV
+	EVP_CIPHER_CTX* ctx = EVP_CIPHER_CTX_new();
+	EVP_DecryptInit_ex(ctx, EVP_aes_256_cbc(), NULL, key, iv);
+
+	// Allocate a string buffer for the decrypted data
+	std::string dst;
+	dst.resize(srclen + EVP_CIPHER_block_size(EVP_aes_256_cbc()));
+
+	// Decrypt the input data
+	int outlen;
+	EVP_DecryptUpdate(ctx, (unsigned char*)dst.data(), &outlen, src, srclen);
+
+	// Finalize the decryption and retrieve any remaining data
+	int finaloutlen;
+	EVP_DecryptFinal_ex(ctx, (unsigned char*)dst.data() + outlen, &finaloutlen);
+
+	// Resize the buffer to the actual decrypted length
+	dst.resize(outlen + finaloutlen);
+
+	// Free the encryption context
+	EVP_CIPHER_CTX_free(ctx);
+
+	// Clean up resources
+	BN_free(priv_bn);
+	BN_free(pub_bn);
+	EC_KEY_free(priv_key);
+	EC_KEY_free(pub_key);
+	EVP_cleanup();
+
+	return FString(dst.c_str());
+}
+
+FString UECCrypto::encrypt(FString data, FString privateKeyHex, FString ephemPublicKeyHex, FString encryptionIvHex)
+{
+	// Convert to bytes array
+	const char* priv_hex = FStringToCharArray(privateKeyHex);
+	const char* pub_hex = FStringToCharArray(ephemPublicKeyHex);
+
+	// Decode IV key
+	const unsigned char* iv = toByteArray(FStringToCharArray(encryptionIvHex));
+
+	// Decode cipher text
+	const unsigned char* src = (unsigned char*)FStringToCharArray(data);
+	int srclen = data.Len() / 2;
+
+	// Convert to BIGNUM
+	BIGNUM* priv_bn = BN_new();
+	BIGNUM* pub_bn = BN_new();
+	BN_hex2bn(&priv_bn, priv_hex);
+	BN_hex2bn(&pub_bn, pub_hex);
+
+	// Create EC_KEY objects from the BIGNUMs
+	EC_KEY* priv_key = EC_KEY_new_by_curve_name(NID_secp256k1);
+	EC_KEY* pub_key = EC_KEY_new_by_curve_name(NID_secp256k1);
+	EC_KEY_set_private_key(priv_key, priv_bn);
+	EC_KEY_set_public_key(pub_key, EC_POINT_bn2point(EC_KEY_get0_group(pub_key), pub_bn, NULL, NULL));
+
+	// Create the shared secret
+	unsigned char* secret = new unsigned char[32];
+	int secret_len = ECDH_compute_key(secret, EVP_MAX_KEY_LENGTH, EC_KEY_get0_public_key(pub_key), priv_key, NULL);
+
+	// Calculate SHA-512 hash of secret
+	unsigned char hash[SHA512_DIGEST_LENGTH];
+	SHA512(secret, 32, hash);
+
+	// Copy first 32 bytes of the hash into a new buffer
+	unsigned char key[32];
+	memcpy(key, hash, 32);
+
+	// Create a new encryption context for AES-256 CBC mode with the key and IV
+	EVP_CIPHER_CTX* ctx = EVP_CIPHER_CTX_new();
+	EVP_EncryptInit_ex(ctx, EVP_aes_256_cbc(), NULL, key, iv);
+
+	// Allocate a string buffer for the decrypted data
+	std::string dst;
+	dst.resize(srclen + EVP_CIPHER_block_size(EVP_aes_256_cbc()));
+
+	// Decrypt the input data
+	int outlen;
+	EVP_EncryptUpdate(ctx, (unsigned char*)dst.data(), &outlen, src, srclen);
+
+	// Finalize the decryption and retrieve any remaining data
+	int finaloutlen;
+	EVP_EncryptFinal_ex(ctx, (unsigned char*)dst.data() + outlen, &finaloutlen);
+
+	// Resize the buffer to the actual decrypted length
+	dst.resize(outlen + finaloutlen);
+
+	// Free the encryption context
+	EVP_CIPHER_CTX_free(ctx);
+
+	// Clean up resources
+	BN_free(priv_bn);
+	BN_free(pub_bn);
+	EC_KEY_free(priv_key);
+	EC_KEY_free(pub_key);
+	EVP_cleanup();
+
+	return FString(UTF8_TO_TCHAR(dst.c_str()));
+}
+
+FString UECCrypto::generatePublicKey(const FString& privateKeyHex) {
+	BIGNUM* bn_private_key = NULL;
+	BN_hex2bn(&bn_private_key, TCHAR_TO_ANSI(*privateKeyHex));
+
+	EC_KEY* ec_key = EC_KEY_new_by_curve_name(NID_secp256k1);
+	EC_KEY_set_private_key(ec_key, bn_private_key);
+
+	EC_POINT* ec_point = EC_POINT_new(EC_KEY_get0_group(ec_key));
+	EC_POINT_mul(EC_KEY_get0_group(ec_key), ec_point, EC_KEY_get0_private_key(ec_key), NULL, NULL, NULL);
+	EC_KEY_set_public_key(ec_key, ec_point);
+
+	BIGNUM* bn = EC_POINT_point2bn(EC_KEY_get0_group(ec_key), EC_KEY_get0_public_key(ec_key), POINT_CONVERSION_UNCOMPRESSED, NULL, NULL);
+
+	char* hex = BN_bn2hex(bn);
+	FString result(UTF8_TO_TCHAR(hex));
+
+	OPENSSL_free(hex);
+	BN_free(bn_private_key);
+
+	return result.ToLower();
+}
+
+FString UECCrypto::generateECDSASignature(const FString& privateKeyHex, const FString& data) {
+	// Initialize OpenSSL's elliptic curve library
+	EC_KEY* key = EC_KEY_new_by_curve_name(NID_secp256k1);
+
+	BIGNUM* priv_bn = BN_new();
+	BN_hex2bn(&priv_bn, FStringToCharArray(privateKeyHex));
+
+	EC_KEY_set_private_key(key, priv_bn);
+
+	const unsigned char* msg = (const unsigned char* ) FStringToCharArray(data);
+	size_t msglen = data.Len();
+
+	unsigned char hash[SHA256_DIGEST_LENGTH];
+	Keccak256::getHash(msg, msglen, hash);
+
+	unsigned char* sig_buf = nullptr;
+
+	ECDSA_SIG* signature = ECDSA_do_sign(hash, SHA256_DIGEST_LENGTH, key);
+	int n = i2d_ECDSA_SIG(signature, &sig_buf);
+
+	//// Convert signature to hex string    
+	FString signature_hex;    
+	for (int i = 0; i < n; ++i) {        
+		signature_hex += FString::Printf(TEXT("%02x"), sig_buf[i]);    
+	}
+
+	EC_KEY_free(key);
+	ECDSA_SIG_free(signature);
+
+	return signature_hex;
+}
+
+UECCrypto::~UECCrypto()
+{
+}
+
+

Plugins/Web3AuthSDK/Source/Web3AuthSDK/Private/Keccak256.cpp

@@ -0,0 +1,101 @@
+/*
+ * Bitcoin cryptography library
+ * Copyright (c) Project Nayuki
+ *
+ * https://www.nayuki.io/page/bitcoin-cryptography-library
+ * https://github.com/nayuki/Bitcoin-Cryptography-Library
+ */
+
+#include "Keccak256.h"
+#include <cassert>
+
+using std::uint8_t;
+using std::uint64_t;
+using std::size_t;
+
+
+void Keccak256::getHash(const uint8_t msg[], size_t len, uint8_t hashResult[HASH_LEN]) {
+	assert((msg != nullptr || len == 0) && hashResult != nullptr);
+	uint64_t state[5][5] = {};
+
+	// XOR each message byte into the state, and absorb full blocks
+	int blockOff = 0;
+	for (size_t i = 0; i < len; i++) {
+		int j = blockOff >> 3;
+		state[j % 5][j / 5] ^= static_cast<uint64_t>(msg[i]) << ((blockOff & 7) << 3);
+		blockOff++;
+		if (blockOff == BLOCK_SIZE) {
+			absorb(state);
+			blockOff = 0;
+		}
+	}
+
+	// Final block and padding
+	{
+		int i = blockOff >> 3;
+		state[i % 5][i / 5] ^= UINT64_C(0x01) << ((blockOff & 7) << 3);
+		blockOff = BLOCK_SIZE - 1;
+		int j = blockOff >> 3;
+		state[j % 5][j / 5] ^= UINT64_C(0x80) << ((blockOff & 7) << 3);
+		absorb(state);
+	}
+
+	// Uint64 array to bytes in little endian
+	for (int i = 0; i < HASH_LEN; i++) {
+		int j = i >> 3;
+		hashResult[i] = static_cast<uint8_t>(state[j % 5][j / 5] >> ((i & 7) << 3));
+	}
+}
+
+
+void Keccak256::absorb(uint64_t state[5][5]) {
+	uint64_t(*a)[5] = state;
+	uint8_t r = 1;  // LFSR
+	for (int i = 0; i < NUM_ROUNDS; i++) {
+		// Theta step
+		uint64_t c[5] = {};
+		for (int x = 0; x < 5; x++) {
+			for (int y = 0; y < 5; y++)
+				c[x] ^= a[x][y];
+		}
+		for (int x = 0; x < 5; x++) {
+			uint64_t d = c[(x + 4) % 5] ^ rotl64(c[(x + 1) % 5], 1);
+			for (int y = 0; y < 5; y++)
+				a[x][y] ^= d;
+		}
+
+		// Rho and pi steps
+		uint64_t b[5][5];
+		for (int x = 0; x < 5; x++) {
+			for (int y = 0; y < 5; y++)
+				b[y][(x * 2 + y * 3) % 5] = rotl64(a[x][y], ROTATION[x][y]);
+		}
+
+		// Chi step
+		for (int x = 0; x < 5; x++) {
+			for (int y = 0; y < 5; y++)
+				a[x][y] = b[x][y] ^ (~b[(x + 1) % 5][y] & b[(x + 2) % 5][y]);
+		}
+
+		// Iota step
+		for (int j = 0; j < 7; j++) {
+			a[0][0] ^= static_cast<uint64_t>(r & 1) << ((1 << j) - 1);
+			r = static_cast<uint8_t>((r << 1) ^ ((r >> 7) * 0x171));
+		}
+	}
+}
+
+
+uint64_t Keccak256::rotl64(uint64_t x, int i) {
+	return ((0U + x) << i) | (x >> ((64 - i) & 63));
+}
+
+
+// Static initializers
+const unsigned char Keccak256::ROTATION[5][5] = {
+	{ 0, 36,  3, 41, 18},
+	{ 1, 44, 10, 45,  2},
+	{62,  6, 43, 15, 61},
+	{28, 55, 25, 21, 56},
+	{27, 20, 39,  8, 14},
+};

Plugins/Web3AuthSDK/Source/Web3AuthSDK/Private/KeyStoreUtils.cpp

@@ -0,0 +1,30 @@
+#include "KeyStoreUtils.h"
+
+UKeyStoreUtils::UKeyStoreUtils() {
+	StorageInstance = Cast<UWeb3StorageAdapter>(UGameplayStatics::LoadGameFromSlot(TEXT("Web3AuthDataSlot"), 0));
+	if(StorageInstance == nullptr) {
+		StorageInstance = Cast<UWeb3StorageAdapter>(UGameplayStatics::CreateSaveGameObject(UWeb3StorageAdapter::StaticClass()));
+	}
+}
+
+UKeyStoreUtils::~UKeyStoreUtils() {
+}
+
+void UKeyStoreUtils::Add(FString key, FString value) {
+	StorageInstance->KeyValuePairs.Add(key, value);
+	UGameplayStatics::SaveGameToSlot(StorageInstance, TEXT("Web3AuthDataSlot"), 0);
+}
+
+FString UKeyStoreUtils::Get(FString key) {
+	if (StorageInstance->KeyValuePairs.Contains(key)) {
+		return StorageInstance->KeyValuePairs[key];
+	}
+	return "";
+}
+
+void UKeyStoreUtils::Remove(FString key) {
+	if (StorageInstance->KeyValuePairs.Contains(key)) {
+		StorageInstance->KeyValuePairs.Remove(key);
+		UGameplayStatics::SaveGameToSlot(StorageInstance, TEXT("Web3AuthDataSlot"), 0);
+	}
+}