#include "appleauth/iauth.h"
#include "tier2/fileformats/plist.h"
#include "http/http.h"
#include "openssl/srp.h"
#include "openssl/evp.h"
#include "openssl/sha.h"
#include "tier0/rand.h"

IHTTPClientManager *g_pHttpClientMgr = NULL;
static int base64_decode(const char *b64, unsigned char *pOut) {
	int len = strlen(b64);
	if (pOut == NULL)
		return (len*3)/4;
	int out_len = EVP_DecodeBlock(pOut,
			(const unsigned char *)b64,
			len);
	if (out_len < 0)
		return -1;

	while (len > 0 && b64[len - 1] == '=') {
		out_len--;
		len--;
	}

	return out_len;
}

// autogenerated
#define APPLE_LOCAL_USER "e2e70285da39596ef06153b9c4e1e5dc8d2f983bc5cd63f5b1e292207060d931"
#define APPLE_HTTP_HEADER \
{ \
	{"X-Apple-I-Client-Time", "2026-1-9T12:00:00"}, \
	{"X-Apple-Locale", "en_US"}, \
	{"X-Apple-I-TimeZone", "Europe/Kyiv"}, \
	{"X-Mme-Client-Info", "<MacBookPro13,2> <macOS;13.1;22C65> <com.apple.AuthKit/1 (com.apple.dt.Xcode/3594.4.19)>"}, \
	{"User-Agent", "akd/1.0 CFNetwork/808.1.4"}, \
	{"X-Apple-I-MD-LU", APPLE_LOCAL_USER}, \
	{"X-Apple-I-MD-M", "0"}, \
	{"X-Apple-I-SRL-NO", "0"}, \
	{"X-Mme-Device-Id", "0"}, \
	{"Content-Type", "text/x-xml-plist"}, \
	{"Accept", "*/*"}, \
};

#define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
#define G2048 "2"
enum EPasswordType
{
	PASSWORD_TYPE_S2K,
	PASSWORD_TYPE_S2K_FO,
};

class CAppleAuth: public IAppleAuth 
{
public:
	virtual void Init() override;
	virtual void Shutdown() override;
	virtual void LaunchLoginDaemon() override;
	virtual EAppleAuthDaemonStatus GetStatus() override;
	virtual EAppleAuthStatus SubmitLoginData( const char *szEmail, const char *szPassword ) override;
	virtual EAppleAuthStatus Submit2FA( const char *szCode ) override;
	virtual CUtlString EncryptPassword( const char *szPassword, CUtlString szSalt, uint32_t uIters, EPasswordType eType );
	void ComputeM1( unsigned char M1[SHA256_DIGEST_LENGTH], const BIGNUM *N, const BIGNUM *g, const char *username, const char *password, const unsigned char *salt, size_t salt_len, const BIGNUM *A, const BIGNUM *B, const BIGNUM *a );

	CUtlString FetchADIPB();
	void FetchHeaders( CUtlString szAdiPb );

	IHTTPClient *m_pANIClient;
	IHTTPClient *m_pGrandSlamClient;

	CUtlString m_szProvisionStart = "/grandslam/MidService/startMachineProvisioning";
	CUtlString m_szProvisionFinish = "/grandslam/MidService/finishMachineProvisioning";
	IJSONObject *pHeader;

	CUtlString m_szAppleIMD;
	CUtlString m_szAppleIMDM;
	CUtlString m_szAppleIMDRINFO;

};

CUtlString CAppleAuth::FetchADIPB()
{

	CUtlString szProvisionExpectedInputRaw = NULL;
	IJSONObject *pObject = NULL;
	IJSONObject *pPlistObject = NULL;
	CUtlString szProvisionExpectedInput = NULL;
	CUtlString szAdiPb = NULL;

	m_pANIClient = g_pHttpClientMgr->Connect("ani.sidestore.io", true, NULL);

	{
		HTTPHeaderParam_t params[] = APPLE_HTTP_HEADER;
		HTTPHeader_t header = {
			sizeof(params)/sizeof(HTTPHeaderParam_t),
			params,
		};
		m_pGrandSlamClient->Get("/grandslam/GsService2/lookup", &header);
		HTTPResponse_t r = m_pGrandSlamClient->GetResponse();
		if ( r.m_uCode != 200 )
		{
			g_pHttpClientMgr->Disconnect(m_pANIClient);
			return NULL;
		}
	}

	if ( !m_pANIClient->WebSocket_Connect("/v3/provisioning_session") )
		Plat_FatalErrorFunc("Failed to init AppleAuth websocket\n");

	// Getting adipb
	while ( ( szProvisionExpectedInputRaw = m_pANIClient->WebSocket_RecvText() ) != NULL )
	{
		pObject = JSONManager()->ReadString(szProvisionExpectedInputRaw);
		szProvisionExpectedInput = pObject->GetValue("result")->GetStringValue();
		V_printf("%s\n",szProvisionExpectedInput.GetString());
		if ( szProvisionExpectedInput == "GiveIdentifier" )
		{
			m_pANIClient->WebSocket_SendText("{\"identifier\": \"" APPLE_LOCAL_USER "\"}");	
			continue;
		}
		if ( szProvisionExpectedInput == "GiveStartProvisioningData" )
		{
			const char *plist =
			"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
			"<!DOCTYPE plist PUBLIC \"-//Apple//DTD PLIST 1.0//EN\" "
			"\"http://www.apple.com/DTDs/PropertyList-1.0.dtd\">\n"
			"<plist version=\"1.0\">\n"
			"<dict>\n"
			"\t<key>Header</key>\n"
			"\t<dict/>\n"
			"\t<key>Request</key>\n"
			"\t<dict/>\n"
			"</dict>\n"
			"</plist>\n";

			HTTPHeaderParam_t params[] = APPLE_HTTP_HEADER;
			HTTPHeader_t header = {
				sizeof(params)/sizeof(HTTPHeaderParam_t),
				params,
			};
			m_pGrandSlamClient->Post(m_szProvisionStart, &header, V_strlen(plist), plist);
			HTTPResponse_t r = m_pGrandSlamClient->GetResponse();
			if ( r.m_uCode != 200 )
			{
				g_pHttpClientMgr->Disconnect(m_pANIClient);
				return NULL;
			}
			IJSONObject *pObject = PropertyListManager()->ReadString(r.m_message);
			CUtlString spim = pObject->GetValue("Response")->GetObject()->GetValue("spim")->GetStringValue();
			m_pANIClient->WebSocket_SendText(CUtlString("{\"spim\": \"%s\"}", spim.GetString()));	
			
			continue;
		}
		if ( szProvisionExpectedInput == "GiveEndProvisioningData" )
		{
			CUtlString cpim = pObject->GetValue("cpim")->GetStringValue();

			CUtlString plist = CUtlString(
			"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
			"<!DOCTYPE plist PUBLIC \"-//Apple//DTD PLIST 1.0//EN\" "
			"\"http://www.apple.com/DTDs/PropertyList-1.0.dtd\">\n"
			"<plist version=\"1.0\">\n"
			"<dict>\n"
			"\t<key>Header</key>\n"
			"\t<dict/>\n"
			"\t<key>Request</key>\n"
			"\t<dict>\n"
			"\t<key>cpim</key>\n"
			"\t<string>%s</string>\n"
			"\t</dict>\n"
			"</dict>\n"
			"</plist>\n", cpim.GetString());

			HTTPHeaderParam_t params[] = APPLE_HTTP_HEADER;
			HTTPHeader_t header = {
				sizeof(params)/sizeof(HTTPHeaderParam_t),
				params,
			};
			m_pGrandSlamClient->Post(m_szProvisionFinish, &header, V_strlen(plist), plist);
			HTTPResponse_t r = m_pGrandSlamClient->GetResponse();
			if ( r.m_uCode != 200 )
			{
				g_pHttpClientMgr->Disconnect(m_pANIClient);
				return NULL;
			}
			IJSONObject *pObject = PropertyListManager()->ReadString(r.m_message);
			CUtlString tk = pObject->GetValue("Response")->GetObject()->GetValue("tk")->GetStringValue();
			CUtlString ptm = pObject->GetValue("Response")->GetObject()->GetValue("ptm")->GetStringValue();

			V_printf("%s\n",CUtlString("{\"tk\": \"%s\", \"ptm\": \"%s\"}", tk.GetString(), ptm.GetString()).GetString());
			m_pANIClient->WebSocket_SendText(CUtlString("{\"tk\": \"%s\", \"ptm\": \"%s\"}", tk.GetString(), ptm.GetString()));	
			
			continue;
		}
		if ( szProvisionExpectedInput == "ProvisioningSuccess" )
		{
			szAdiPb = pObject->GetValue("adi_pb")->GetStringValue();
			g_pHttpClientMgr->Disconnect(m_pANIClient);
			break;
		}
		if ( szProvisionExpectedInput == "Timeout" )
		{
			break;
		}
		g_pHttpClientMgr->Disconnect(m_pANIClient);
		return NULL;
	}
	g_pHttpClientMgr->Disconnect(m_pANIClient);
	return szAdiPb;
}
void CAppleAuth::FetchHeaders( CUtlString szAdiPb )
{
	// Get header
	HTTPHeaderParam_t params[] = {
		"Content-Type", "application/json",
	};
	HTTPHeader_t header = {
		sizeof(params)/sizeof(HTTPHeaderParam_t),
		params,
	};
	m_pANIClient = g_pHttpClientMgr->Connect("ani.sidestore.io", true, NULL);
	CUtlString szPostData = CUtlString("{\"identifier\": \"" APPLE_LOCAL_USER "\", \"adi_pb\": \"%s\"}", szAdiPb.GetString());
	V_printf("%s\n",szPostData.GetString());
	m_pANIClient->Post("/v3/get_headers", &header, V_strlen(szPostData), szPostData);	
	HTTPResponse_t r = m_pANIClient->GetResponse();
	V_printf("%i\n",r.m_uCode);
	if ( r.m_uCode == 200 )
	{
		V_printf("%s\n",r.m_message.GetMemory());
		pHeader = JSONManager()->ReadString(r.m_message);
		m_szAppleIMD = pHeader->GetValue("X-Apple-I-MD")->GetStringValue();
		m_szAppleIMDM = pHeader->GetValue("X-Apple-I-MD-M")->GetStringValue();
		m_szAppleIMDRINFO = pHeader->GetValue("X-Apple-I-MD-RINFO")->GetStringValue();
		JSONManager()->FreeObject(pHeader);
	}
	g_pHttpClientMgr->Disconnect(m_pANIClient);
}

void CAppleAuth::Init()
{
	CreateInterfaceFn fnHttpFactory = Sys_GetFactory("funnyhttp");

	g_pHttpClientMgr = (IHTTPClientManager*)fnHttpFactory(HTTP_CLIENT_INTERFACE_VERSION, NULL);
	
	m_pGrandSlamClient = g_pHttpClientMgr->Connect("gsa.apple.com", true, NULL);

	CUtlString szAdiPb = FetchADIPB();
	FetchHeaders(szAdiPb);



}

void CAppleAuth::Shutdown()
{

}

void CAppleAuth::LaunchLoginDaemon()
{


}

EAppleAuthDaemonStatus CAppleAuth::GetStatus()
{
	return APPLE_AUTH_DAEMON_NOT_LOGGED_IN;
}


EAppleAuthStatus CAppleAuth::SubmitLoginData( const char *szEmail, const char *szPassword )
{
	const char *pszUser = szEmail;
	const char *pszPass = szPassword;

	BIGNUM* pN = BN_new(); 
	BIGNUM* pG = BN_new(); 
	BIGNUM* pa = BN_new(); 
	BIGNUM* pA = BN_new(); 
	BN_CTX *pbnCtx = BN_CTX_new();

	SHA256_CTX pSha;
	unsigned char pK[SHA256_DIGEST_LENGTH];
	BN_hex2bn(&pN, N2048);
	BN_hex2bn(&pG, G2048);
	CUtlBuffer<unsigned char> bN;
	CUtlBuffer<unsigned char> bG;
	bN = CUtlBuffer<unsigned char>(BN_num_bytes(pN));
	bG = CUtlBuffer<unsigned char>(BN_num_bytes(pG));
	BN_bn2bin(pN, bN.GetMemory());
	SHA256_Init(&pSha);
	SHA256_Update(&pSha, bN.GetMemory(), bN.GetSize());
	SHA256_Update(&pSha, bG.GetMemory(), bG.GetSize());
	SHA256_Final(pK, &pSha);
	
	BN_rand(pa, 256, 0, 0);
	BN_set_flags(pa, BN_FLG_CONSTTIME);
	BN_mod_exp(pA, pG, pa, pN, pbnCtx);

	char *pszA = BN_bn2hex(pA);

	CUtlString plist = CUtlString(
	"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
	"<!DOCTYPE plist PUBLIC \"-//Apple//DTD PLIST 1.0//EN\" "
	"\"http://www.apple.com/DTDs/PropertyList-1.0.dtd\">\n"
	"<plist version=\"1.0\">\n"
	"<dict>\n"
	"\t<key>Header</key>\n"
	"\t<dict>\n"
	"\t<key>Version</key>\n"
	"\t<string>1.0.1</string>\n"
	"\t</dict>\n"

	"\t<key>Request</key>\n"
	"\t<dict>\n"

	"\t<key>A2k</key>\n"
	"\t<data>%s</data>\n"

	"\t<key>ps</key>\n"
	"\t<array><string>s2k</string><string>s2k_fo</string></array>\n"

	"\t<key>u</key>\n"
	"\t<string>%s</string>\n"

	"\t<key>o</key>\n"
	"\t<string>init</string>\n"

	"\t<key>cpd</key>\n"
	"\t<dict>\n"
	
	"\t<key>X-Apple-I-Client-Time</key>\n"
	"\t<string>2026-1-9T12:00:00Z</string>\n"
	"\t<key>X-Apple-I-MD</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Apple-I-MD-LU</key>\n"
	"\t<string>" APPLE_LOCAL_USER "</string>\n"
	"\t<key>X-Apple-I-MD-M</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Apple-I-MD-RINFO</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Mme-Client-Info</key>\n"
	"\t<string>&lt;MacBookPro13,2&gt; &lt;macOS;13.1;22C65&gt; &lt;com.apple.AuthKit/1 (com.apple.dt.Xcode/3594.4.19)&gt;</string>\n"
	"\t<key>X-Apple-I-SRL-NO</key>\n"
	"\t<string>0</string>\n"


	"\t<key>bootstrap</key>\n"
	"\t<trur/>\n"

	"\t<key>icscrec</key>\n"
	"\t<true/>\n"
	

	"\t<key>pbe</key>\n"
	"\t<false/>\n"

	"\t<key>prkgen</key>\n"
	"\t<true/>\n"

	"\t<key>svct</key>\n"
	"\t<string>iCloud</string>\n"

	"\t<key>loc</key>\n"
	"\t<string>en_US</string>\n"

	"\t</dict>\n"

	"\t</dict>\n"
	"</dict>\n"
	"</plist>\n", pszA, szEmail, m_szAppleIMD.GetString(), m_szAppleIMDM.GetString(), m_szAppleIMDRINFO.GetString());
	HTTPHeaderParam_t params[] = {
		{"Content-Type", "text/x-xml-plist"},
		{"Accept", "*/*"},
		{"User-Agent", "akd/1.0 CFNetwork/808.1.4"}, \
		{"X-Mme-Client-Info", "<MacBookPro13,2> <macOS;13.1;22C65> <com.apple.AuthKit/1 (com.apple.dt.Xcode/3594.4.19)>"}, \
	};
	HTTPHeader_t header = {
		sizeof(params)/sizeof(HTTPHeaderParam_t),
		params,
	};
	V_printf("%s\n",plist.GetString());
	m_pGrandSlamClient->Post("/grandslam/GsService2", &header, plist.GetLenght(), plist);
	HTTPResponse_t stResponse = m_pGrandSlamClient->GetResponse();
	V_printf("%i %i\n", stResponse.m_uCode, stResponse.m_bIsComplete);
	if (stResponse.m_uCode != 200)
		return APPLE_AUTH_FAILURE;
	V_printf("%s\n",stResponse.m_message.GetMemory());
	IJSONObject *pObject = PropertyListManager()->ReadString(stResponse.m_message);
	IJSONObject *pResponse = pObject->GetValue("Response")->GetObject();
	CUtlString szEncryptedPassword = EncryptPassword(szPassword, pResponse->GetValue("s")->GetStringValue(), pResponse->GetValue("i")->GetNumberValue(), PASSWORD_TYPE_S2K);
	const char *szSalt = pResponse->GetValue("s")->GetStringValue();
	const char *szB = pResponse->GetValue("B")->GetStringValue();
	unsigned char salt[32];
	int iSaltLen = base64_decode(szSalt, salt);

	int iBLen = base64_decode(szB, NULL);
	CUtlBuffer<unsigned char> BBuffer = CUtlBuffer<unsigned char>(iBLen);
	iBLen = base64_decode(szB, BBuffer.GetMemory());
	BIGNUM *pB = BN_bin2bn(BBuffer.GetMemory(), BBuffer.GetSize(), NULL); 
	unsigned char M1[SHA256_DIGEST_LENGTH];
	ComputeM1(M1, pN, pG, szEmail, szPassword, salt, iSaltLen, pA, pB, pa);

	CUtlString szM1 = {};
	for ( int i = 0; i < SHA256_DIGEST_LENGTH; i++ )
	{
		szM1.AppendTail(CUtlString("%02x", M1[i]));
	}

	plist = CUtlString(
	"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
	"<!DOCTYPE plist PUBLIC \"-//Apple//DTD PLIST 1.0//EN\" "
	"\"http://www.apple.com/DTDs/PropertyList-1.0.dtd\">\n"
	"<plist version=\"1.0\">\n"
	"<dict>\n"
	"\t<key>Header</key>\n"
	"\t<dict>\n"
	"\t<key>Version</key>\n"
	"\t<string>1.0.1</string>\n"
	"\t</dict>\n"

	"\t<key>Request</key>\n"
	"\t<dict>\n"

	"\t<key>M1</key>\n"
	"\t<data>%s</data>\n"

	"\t<key>c</key>\n"
	"\t<string>%s</string>\n"

	"\t<key>ps</key>\n"
	"\t<array><string>s2k</string><string>s2k_fo</string></array>\n"

	"\t<key>u</key>\n"
	"\t<string>%s</string>\n"

	"\t<key>o</key>\n"
	"\t<string>complete</string>\n"

	"\t<key>cpd</key>\n"
	"\t<dict>\n"
	
	"\t<key>X-Apple-I-Client-Time</key>\n"
	"\t<string>2026-1-9T12:00:00Z</string>\n"
	"\t<key>X-Apple-I-MD</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Apple-I-MD-LU</key>\n"
	"\t<string>" APPLE_LOCAL_USER "</string>\n"
	"\t<key>X-Apple-I-MD-M</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Apple-I-MD-RINFO</key>\n"
	"\t<string>%s</string>\n"
	"\t<key>X-Mme-Client-Info</key>\n"
	"\t<string>&lt;MacBookPro13,2&gt; &lt;macOS;13.1;22C65&gt; &lt;com.apple.AuthKit/1 (com.apple.dt.Xcode/3594.4.19)&gt;</string>\n"
	"\t<key>X-Apple-I-SRL-NO</key>\n"
	"\t<string>0</string>\n"


	"\t<key>bootstrap</key>\n"
	"\t<trur/>\n"

	"\t<key>icscrec</key>\n"
	"\t<true/>\n"
	

	"\t<key>pbe</key>\n"
	"\t<false/>\n"

	"\t<key>prkgen</key>\n"
	"\t<true/>\n"

	"\t<key>svct</key>\n"
	"\t<string>iCloud</string>\n"

	"\t<key>loc</key>\n"
	"\t<string>en_US</string>\n"

	"\t</dict>\n"

	"\t</dict>\n"
	"</dict>\n"
	"</plist>\n", szM1.GetString(), pResponse->GetValue("c")->GetStringValue(), szEmail, m_szAppleIMD.GetString(), m_szAppleIMDM.GetString(), m_szAppleIMDRINFO.GetString());
	V_printf("%s\n", plist.GetString());
	m_pGrandSlamClient->Post("/grandslam/GsService2", &header, plist.GetLenght(), plist);
	stResponse = m_pGrandSlamClient->GetResponse();
	V_printf("%i %i\n", stResponse.m_uCode, stResponse.m_bIsComplete);
	if (stResponse.m_uCode != 200)
		return APPLE_AUTH_FAILURE;
	V_printf("%s\n", stResponse.m_message.GetMemory());

	g_pHttpClientMgr->Disconnect(m_pGrandSlamClient);


	OPENSSL_free(pszA);
	return APPLE_AUTH_SUCCESS;
}

static void hash_bn_pad(unsigned char out[SHA256_DIGEST_LENGTH], const BIGNUM *bn)
{
	unsigned char buf[256];
	memset(buf, 0, sizeof(buf));

	int len = BN_num_bytes(bn);
	BN_bn2bin(bn, buf + (256 - len));

	SHA256(buf, 256, out);
}

void CAppleAuth::ComputeM1(
	unsigned char M1[SHA256_DIGEST_LENGTH],
	const BIGNUM *N,
	const BIGNUM *g,
	const char *username,
	const char *password,
	const unsigned char *salt, size_t salt_len,
	const BIGNUM *A,
	const BIGNUM *B,
	const BIGNUM *a
)
{
	SHA256_CTX ctx;
	unsigned char HN[SHA256_DIGEST_LENGTH], Hg[SHA256_DIGEST_LENGTH], HNxorg[SHA256_DIGEST_LENGTH];
	unsigned char HI[SHA256_DIGEST_LENGTH];

	/* H(N) xor H(g) */
	hash_bn_pad(HN, N);
	hash_bn_pad(Hg, g);
	for (int i = 0; i < SHA256_DIGEST_LENGTH; i++)
		HNxorg[i] = HN[i] ^ Hg[i];

	/* H(I) */
	SHA256((const unsigned char *)username, strlen(username), HI);

	/* x = H(s || H(I ":" P)) */
	unsigned char inner_hash[SHA256_DIGEST_LENGTH];
	SHA256_Init(&ctx);
	SHA256_Update(&ctx, (const unsigned char *)username, strlen(username));
	SHA256_Update(&ctx, (const unsigned char *)":", 1);
	SHA256_Update(&ctx, (const unsigned char *)password, strlen(password));
	SHA256_Final(inner_hash, &ctx);

	unsigned char x_hash[SHA256_DIGEST_LENGTH];
	SHA256_Init(&ctx);
	SHA256_Update(&ctx, salt, salt_len);
	SHA256_Update(&ctx, inner_hash, SHA256_DIGEST_LENGTH);
	SHA256_Final(x_hash, &ctx);

	BIGNUM *x = BN_bin2bn(x_hash, SHA256_DIGEST_LENGTH, NULL);

	/* k = H(N || g) */
	unsigned char k_hash[SHA256_DIGEST_LENGTH];
	SHA256_Init(&ctx);
	unsigned char bufN[256], bufg[256];
	memset(bufN, 0, 256); BN_bn2bin(N, bufN + (256 - BN_num_bytes(N)));
	memset(bufg, 0, 256); BN_bn2bin(g, bufg + (256 - BN_num_bytes(g)));
	SHA256_Update(&ctx, bufN, 256);
	SHA256_Update(&ctx, bufg, 256);
	SHA256_Final(k_hash, &ctx);
	BIGNUM *k = BN_bin2bn(k_hash, SHA256_DIGEST_LENGTH, NULL);

	/* u = H(A || B) */
	unsigned char bufA[256], bufB[256], u_hash[SHA256_DIGEST_LENGTH];
	memset(bufA, 0, 256); BN_bn2bin(A, bufA + (256 - BN_num_bytes(A)));
	memset(bufB, 0, 256); BN_bn2bin(B, bufB + (256 - BN_num_bytes(B)));
	SHA256_Init(&ctx);
	SHA256_Update(&ctx, bufA, 256);
	SHA256_Update(&ctx, bufB, 256);
	SHA256_Final(u_hash, &ctx);
	BIGNUM *u = BN_bin2bn(u_hash, SHA256_DIGEST_LENGTH, NULL);

	/* S = (B - k * g^x)^(a + u * x) mod N */
	BN_CTX *bn_ctx = BN_CTX_new();
	BIGNUM *gx = BN_new(), *kgx = BN_new(), *B_sub = BN_new();
	BIGNUM *ux = BN_new(), *exp = BN_new(), *S = BN_new();

	BN_mod_exp(gx, g, x, N, bn_ctx);               /* g^x mod N */
	BN_mod_mul(kgx, k, gx, N, bn_ctx);            /* k * g^x mod N */
	BN_mod_sub(B_sub, B, kgx, N, bn_ctx);         /* B - k*g^x mod N */
	BN_mul(ux, u, x, bn_ctx);                     /* u*x */
	BN_add(exp, a, ux);                           /* a + u*x */
	BN_mod_exp(S, B_sub, exp, N, bn_ctx);         /* S */

	/* K = H(S) */
	unsigned char S_bytes[256];
	memset(S_bytes, 0, 256);
	BN_bn2bin(S, S_bytes + (256 - BN_num_bytes(S)));
	unsigned char K[SHA256_DIGEST_LENGTH];
	SHA256(S_bytes, 256, K);

	/* Compute M1 */
	SHA256_Init(&ctx);
	SHA256_Update(&ctx, HNxorg, SHA256_DIGEST_LENGTH);
	SHA256_Update(&ctx, HI, SHA256_DIGEST_LENGTH);
	SHA256_Update(&ctx, salt, salt_len);
	SHA256_Update(&ctx, bufA, 256);
	SHA256_Update(&ctx, bufB, 256);
	SHA256_Update(&ctx, K, SHA256_DIGEST_LENGTH);
	SHA256_Final(M1, &ctx);

	/* Cleanup */
	BN_free(x); BN_free(k); BN_free(u);
	BN_free(gx); BN_free(kgx); BN_free(B_sub); BN_free(ux); BN_free(exp); BN_free(S);
	BN_CTX_free(bn_ctx);
}

EAppleAuthStatus CAppleAuth::Submit2FA( const char *szCode )
{

}
CUtlString CAppleAuth::EncryptPassword( const char *szPassword, CUtlString szSalt, uint32_t uIters, EPasswordType eType )
{

	unsigned char hashedPassword[SHA256_DIGEST_LENGTH];
	CUtlString szHashedPasswordHex = "";
	unsigned char encryptedPassword[32];
	CUtlString szEncryptedPasswordHex = "";
	unsigned char salt[32];
	int iSaltLen = base64_decode(szSalt, salt);
	
	if ( eType == PASSWORD_TYPE_S2K )
	{
		for ( int i = 0; i < SHA256_DIGEST_LENGTH; i++ )
		{
			szHashedPasswordHex.AppendTail(CUtlString("%02x", hashedPassword[i]));
		}
		PKCS5_PBKDF2_HMAC(szHashedPasswordHex, szHashedPasswordHex.GetLenght(), salt, iSaltLen, uIters, EVP_sha256(), 32, encryptedPassword);
	};
	for ( int i = 0; i < SHA256_DIGEST_LENGTH; i++ )
	{
		szEncryptedPasswordHex.AppendTail(CUtlString("%02x", encryptedPassword[i]));
	}
	V_printf("%s\n",szEncryptedPasswordHex.GetString());
	return szEncryptedPasswordHex;

}


static CAppleAuth s_appleAuth;
EXPOSE_INTERFACE_GLOBALVAR(CAppleAuth, IAppleAuth, APPLE_AUTH_INTERFACE_VERSION, s_appleAuth);