diff --git a/cmake/basegame_sources.cmake b/cmake/basegame_sources.cmake
index 4d41a8ed..8b158d22 100644
--- a/cmake/basegame_sources.cmake
+++ b/cmake/basegame_sources.cmake
@@ -79,6 +79,7 @@ set(CGAME_SOURCES
     ${SOURCE_DIR}/game/bg_misc.c
     ${SOURCE_DIR}/game/bg_pmove.c
     ${SOURCE_DIR}/game/bg_slidemove.c
+    ${SOURCE_DIR}/game/bg_auth.c
 )
 
 # Those are tracked only, causing the whole project to recompile
@@ -110,4 +111,5 @@ set(GAME_MODULE_SHARED_SOURCES
     ${SOURCE_DIR}/qcommon/q_shared.c
 )
 
-set(CGAME_SOURCES_BASEGAME ${CGAME_SOURCES} ${GAME_MODULE_SHARED_SOURCES})
\ No newline at end of file
+set(CGAME_SOURCES_BASEGAME ${CGAME_SOURCES} ${GAME_MODULE_SHARED_SOURCES})
+
diff --git a/code/cgame/cg_consolecmds.c b/code/cgame/cg_consolecmds.c
index 35077fb6..7e85d6ad 100644
--- a/code/cgame/cg_consolecmds.c
+++ b/code/cgame/cg_consolecmds.c
@@ -31,6 +31,9 @@ qboolean modifState[5];
 char modifStrDown[5][MODIFSTR_SIZE];
 char modifStrUp[5][MODIFSTR_SIZE];
 
+extern void BG_OSPAuthInit(void);
+extern void BG_OSPAuthUpdateName(char* str);
+extern void BG_OSPAuthGetSecret(char* str);
 
 void CG_TargetCommand_f(void)
 {
@@ -535,6 +538,25 @@ void CG_OSPPrintTime_f(void)
 	CG_Printf("\nCurrent time: ^3%02d:%02d:%02d (%02d %s %d)\n\n", qtime.tm_hour, qtime.tm_min, qtime.tm_sec, qtime.tm_mday, monthName[qtime.tm_mon], qtime.tm_year + 1900);
 }
 
+void CG_OSPClientAuth_f(void)
+{
+	char secret_str[64];
+
+	trap_Argv(1, secret_str, sizeof(secret_str));
+	if (!atoi(secret_str))
+	{
+		CG_Printf("\n^3 >>>>> Warning: ^7Detected invalid authentication request! (NULL buf) <<<<<\n");
+		return;
+	}
+
+	BG_OSPAuthInit();
+	BG_OSPAuthUpdateName(cgs.clientinfo[cg.clientNum].name);
+	BG_OSPAuthUpdateName(secret_str);
+	memset(secret_str, 0, sizeof(secret_str));
+	BG_OSPAuthGetSecret(secret_str);
+	trap_SendClientCommand(va("htuatneilc %s", secret_str));
+}
+
 
 void CG_OSPModifDown(int layout)
 {
diff --git a/code/cgame/cg_local.h b/code/cgame/cg_local.h
index dbac6ce5..b61f97b2 100644
--- a/code/cgame/cg_local.h
+++ b/code/cgame/cg_local.h
@@ -1948,6 +1948,7 @@ qboolean CG_OSPDrawScoretable(void);
 qboolean CG_ConsoleCommand(void);
 void CG_InitConsoleCommands(void);
 void CG_OSPPrintTime_f(void);
+void CG_OSPClientAuth_f(void);
 void CG_OSPMoTD_f(void);
 void CG_OSPWStatsDown_f(void);
 void CG_OSPWStatsUp_f(void);
diff --git a/code/cgame/cg_servercmds.c b/code/cgame/cg_servercmds.c
index 28b023c3..80921a10 100644
--- a/code/cgame/cg_servercmds.c
+++ b/code/cgame/cg_servercmds.c
@@ -1159,6 +1159,7 @@ void CG_ServerCommand(void)
 //psohtua
 	if (strcmp(cmd, "psohtua") == 0)
 	{
+		CG_OSPClientAuth_f();
 		return;
 	}
 //cp
diff --git a/code/game/bg_auth.c b/code/game/bg_auth.c
new file mode 100644
index 00000000..30485717
--- /dev/null
+++ b/code/game/bg_auth.c
@@ -0,0 +1,322 @@
+#include "../qcommon/q_shared.h"
+/* POINTER defines a generic pointer type */
+typedef unsigned char* POINTER;
+
+/* UINT2 defines a two byte word */
+typedef unsigned short int UINT2;
+
+/* UINT4 defines a four byte word */
+typedef unsigned long int UINT4;
+
+typedef struct
+{
+	UINT4 state[4];             /* state (ABCD) */
+	UINT4 count[2];             /* number of bits, modulo 2^64 (lsb first) */
+	unsigned char buffer[64];           /* input buffer */
+} OSPAUTH_CTX;
+
+static void BG_OSPAuthInit_(OSPAUTH_CTX* context);
+static void BG_OSPAuthUpdate_(OSPAUTH_CTX*, const unsigned char*, unsigned int);
+static void BG_OSPAuthFinal_(unsigned char [16], OSPAUTH_CTX*);
+
+static void BG_OSPAuthMemset_(void* dest, const int val, const int count);
+static void BG_OSPAuthMemcpy_(void* dest, const void* src, const int count);
+
+
+static void BG_OSPAuthTransform_(UINT4 [4], const unsigned char [64]);
+static void BG_OSPAuthEncode_(unsigned char*, UINT4*, unsigned int);
+static void BG_OSPAuthDecode_(UINT4*, const unsigned char*, unsigned int);
+
+void BG_OSPAuthGetKey_(unsigned char* str, int* len);
+
+static unsigned char PADDING[64] =
+{
+	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
+#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
+#define H(x, y, z) ((x) ^ (y) ^ (z))
+#define J(x, y, z) ((y ^ (x | ~z)))
+
+/* ROTATE_LEFT rotates x left n bits. */
+#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
+
+/* FF, GG and HH are transformations for rounds 1, 2 and 3 */
+/* Rotation is separate from addition to prevent recomputation */
+#define FF(a, b, c, d, x, s, i) {(a) += F ((b), (c), (d)) + (x) + i; (a) = ROTATE_LEFT ((a), (s)); a += b;}
+
+#define GG(a, b, c, d, x, s, i) {(a) += G ((b), (c), (d)) + (x) + i; (a) = ROTATE_LEFT ((a), (s)); a += b;}
+
+#define HH(a, b, c, d, x, s, i) {(a) += H ((b), (c), (d)) + (x) + i; (a) = ROTATE_LEFT ((a), (s)); a += b;}
+
+#define JJ(a, b, c, d, x, s, i) {(a) += J ((b), (c), (d)) + (x) + i; (a) = ROTATE_LEFT ((a), (s)); a += b;}
+
+#define S11 7
+#define S12 12
+#define S13 17
+#define S14 22
+#define S21 5
+#define S22 9
+#define S23 14
+#define S24 20
+#define S31 4
+#define S32 11
+#define S33 16
+#define S34 23
+#define S41 6
+#define S42 10
+#define S43 15
+#define S44 21
+
+OSPAUTH_CTX ospAuthCtx;
+
+void BG_OSPAuthInit(void)
+{
+	BG_OSPAuthInit_(&ospAuthCtx);
+}
+
+void BG_OSPAuthUpdateName(char* str)
+{
+	BG_OSPAuthUpdate_(&ospAuthCtx, (unsigned char*)str, strlen(str));
+}
+
+void BG_OSPAuthGetSecret(char* secret)
+{
+	int len;
+	char tmp[16];
+	unsigned char secret_[64];
+	unsigned char digest[16];
+
+	BG_OSPAuthGetKey_(&secret_[0], &len);
+	BG_OSPAuthUpdate_(&ospAuthCtx, secret_, len);
+	BG_OSPAuthFinal_(&digest[0], &ospAuthCtx);
+
+	secret_[0] = 0;
+	len = 0;
+
+	do
+	{
+		Com_sprintf(tmp, sizeof(tmp), "%d", digest[len]);
+		strcat((char*)secret_, tmp);
+	}
+	while (++len < 10);
+
+	strcpy(secret, (char*)secret_);
+}
+
+void BG_OSPAuthGetKey_(unsigned char* str, int* len)
+{
+	int i;
+	int block_0[29] = {0xfb, 0xfb, 0xd5, 0xcf, 0xe7, 0xdb, 0x40, 0x6d, 0x0c, 0x68, 0x84, 0x6f, 0x83, 0xbe, 0x65, 0x91, 0x79, 0xbb, 0x3f, 0xf7, 0xd8, 0xc0, 0xe2, 0x77, 0x8d, 0x7f, 0x9d, 0xdf, 0xe7};
+	int block_1[11] = {0xa7, 0xa9, 0xe7, 0x85, 0x7b, 0x64, 0x01, 0xfb, 0x79, 0xfb, 0xfb};
+	int block_2[13] = {0x65, 0xc8, 0x0d, 0x82, 0x09, 0x84, 0x13, 0x0c, 0x42, 0xdd, 0xc0, 0xee, 0x36};
+
+	(void)block_1;
+	(void)block_2;
+
+	*len = 21;
+
+	for (i = 0; i < *len; ++i)
+	{
+		str[i] = (char)(block_0[6 + i] ^ 0xa2);
+	}
+}
+
+static void BG_OSPAuthInit_(OSPAUTH_CTX* context)
+{
+	context->count[0] = context->count[1] = 0;
+
+	/* Load magic initialization constants.*/
+	context->state[0] = 0x67452301;
+	context->state[1] = 0xefcdab89;
+	context->state[2] = 0x98badcfe;
+	context->state[3] = 0x10325476;
+}
+
+static void BG_OSPAuthUpdate_(OSPAUTH_CTX* context, const unsigned char* input, unsigned int inputLen)
+{
+	unsigned int i, index, partLen;
+
+	/* Compute number of bytes mod 64 */
+	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
+
+	/* Update number of bits */
+	if ((context->count[0] += ((UINT4)inputLen << 3)) < ((UINT4)inputLen << 3))
+		context->count[1]++;
+
+	context->count[1] += ((UINT4)inputLen >> 29);
+
+	partLen = 64 - index;
+
+	/* Transform as many times as possible.*/
+	if (inputLen >= partLen)
+	{
+		BG_OSPAuthMemcpy_((POINTER)&context->buffer[index], (POINTER)input, partLen);
+		BG_OSPAuthTransform_(context->state, context->buffer);
+
+		for (i = partLen; i + 63 < inputLen; i += 64)
+			BG_OSPAuthTransform_(context->state, &input[i]);
+
+		index = 0;
+	}
+	else
+		i = 0;
+
+	/* Buffer remaining input */
+	BG_OSPAuthMemcpy_((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen - i);
+}
+
+
+static void BG_OSPAuthFinal_(unsigned char digest[16], OSPAUTH_CTX* context)
+{
+	unsigned char bits[8];
+	unsigned int index, padLen;
+
+	/* Save number of bits */
+	BG_OSPAuthEncode_(bits, context->count, 8);
+
+	/* Pad out to 56 mod 64.*/
+	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
+	padLen = (index < 56) ? (56 - index) : (120 - index);
+	BG_OSPAuthUpdate_(context, PADDING, padLen);
+
+	/* Append length (before padding) */
+	BG_OSPAuthUpdate_(context, bits, 8);
+
+	/* Store state in digest */
+	BG_OSPAuthEncode_(digest, context->state, 16);
+
+	/* Zeroize sensitive information.*/
+	BG_OSPAuthMemset_((POINTER)context, 0, sizeof(*context));
+}
+
+
+static void BG_OSPAuthTransform_(UINT4 state[4], const unsigned char block[64])
+{
+	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
+
+	BG_OSPAuthDecode_(x, block, 64);
+
+	/* Round 1 */
+	FF(a, b, c, d, x[ 0], S11, 0xd76aa478);
+	FF(d, a, b, c, x[ 1], S12, 0xe8c7b756);
+	FF(c, d, a, b, x[ 2], S13, 0x242070db);
+	FF(b, c, d, a, x[ 3], S14, 0xc1bdceee);
+	FF(a, b, c, d, x[ 4], S11, 0xf57c0faf);
+	FF(d, a, b, c, x[ 5], S12, 0x4787c62a);
+	FF(c, d, a, b, x[ 6], S13, 0xa8304613);
+	FF(b, c, d, a, x[ 7], S14, 0xfd469501);
+	FF(a, b, c, d, x[ 8], S11, 0x698098d8);
+	FF(d, a, b, c, x[ 9], S12, 0x8b44f7af);
+	FF(c, d, a, b, x[10], S13, 0xffff5bb1);
+	FF(b, c, d, a, x[11], S14, 0x895cd7be);
+	FF(a, b, c, d, x[12], S11, 0x6b901122);
+	FF(d, a, b, c, x[13], S12, 0xfd987193);
+	FF(c, d, a, b, x[14], S13, 0xa679438e);
+	FF(b, c, d, a, x[15], S14, 0x49b40821);
+
+	/* Round 2 */
+	GG(a, b, c, d, x[ 1], S21, 0xf61e2562);
+	GG(d, a, b, c, x[ 6], S22, 0xc040b340);
+	GG(c, d, a, b, x[11], S23, 0x265e5a51);
+	GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa);
+	GG(a, b, c, d, x[ 5], S21, 0xd62f105d);
+	GG(d, a, b, c, x[10], S22, 0x02441453);
+	GG(c, d, a, b, x[15], S23, 0xd8a1e681);
+	GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8);
+	GG(a, b, c, d, x[ 9], S21, 0x21e1cde6);
+	GG(d, a, b, c, x[14], S22, 0xc33707d6);
+	GG(c, d, a, b, x[ 3], S23, 0xf4d50d87);
+	GG(b, c, d, a, x[ 8], S24, 0x455a14ed);
+	GG(a, b, c, d, x[13], S21, 0xa9e3e905);
+	GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8);
+	GG(c, d, a, b, x[ 7], S23, 0x676f02d9);
+	GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);
+
+	/* Round 3 */
+	HH(a, b, c, d, x[ 5], S31, 0xfffa3942);
+	HH(d, a, b, c, x[ 8], S32, 0x8771f681);
+	HH(c, d, a, b, x[11], S33, 0x6d9d6122);
+	HH(b, c, d, a, x[14], S34, 0xfde5380c);
+	HH(a, b, c, d, x[ 1], S31, 0xa4beea44);
+	HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9);
+	HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60);
+	HH(b, c, d, a, x[10], S34, 0xbebfbc70);
+	HH(a, b, c, d, x[13], S31, 0x289b7ec6);
+	HH(d, a, b, c, x[ 0], S32, 0xeaa127fa);
+	HH(c, d, a, b, x[ 3], S33, 0xd4ef3085);
+	HH(b, c, d, a, x[ 6], S34, 0x04881d05);
+	HH(a, b, c, d, x[ 9], S31, 0xd9d4d039);
+	HH(d, a, b, c, x[12], S32, 0xe6db99e5);
+	HH(c, d, a, b, x[15], S33, 0x1fa27cf8);
+	HH(b, c, d, a, x[ 2], S34, 0xc4ac5665);
+
+	/* Round 4 */
+	JJ(a, b, c, d, x[ 0], S41, 0xf4292244);
+	JJ(d, a, b, c, x[ 7], S42, 0x432aff97);
+	JJ(c, d, a, b, x[14], S43, 0xab9423a7);
+	JJ(b, c, d, a, x[ 5], S44, 0xfc93a039);
+	JJ(a, b, c, d, x[12], S41, 0x655b59c3);
+	JJ(d, a, b, c, x[ 3], S42, 0x8f0ccc92);
+	JJ(c, d, a, b, x[10], S43, 0xffeff47d);
+	JJ(b, c, d, a, x[ 1], S44, 0x85845dd1);
+	JJ(a, b, c, d, x[ 8], S41, 0x6fa87e4f);
+	JJ(d, a, b, c, x[15], S42, 0xfe2ce6e0);
+	JJ(c, d, a, b, x[ 6], S43, 0xa3014314);
+	JJ(b, c, d, a, x[13], S44, 0x4e0811a1);
+	JJ(a, b, c, d, x[ 4], S41, 0xf7537e82);
+	JJ(d, a, b, c, x[11], S42, 0xbd3af235);
+	JJ(c, d, a, b, x[ 2], S43, 0x2ad7d2bb);
+	JJ(b, c, d, a, x[ 9], S44, 0xeb86d391);
+
+	state[0] += a;
+	state[1] += b;
+	state[2] += c;
+	state[3] += d;
+
+	BG_OSPAuthMemset_((POINTER)x, 0, sizeof(x));
+}
+
+
+static void BG_OSPAuthEncode_(unsigned char* output, UINT4* input, unsigned int len)
+{
+	unsigned int i, j;
+
+	for (i = 0, j = 0; j < len; i++, j += 4)
+	{
+		output[j] = (unsigned char)(input[i] & 0xff);
+		output[j + 1] = (unsigned char)((input[i] >> 8) & 0xff);
+		output[j + 2] = (unsigned char)((input[i] >> 16) & 0xff);
+		output[j + 3] = (unsigned char)((input[i] >> 24) & 0xff);
+	}
+}
+
+
+static void BG_OSPAuthDecode_(UINT4* output, const unsigned char* input, unsigned int len)
+{
+	unsigned int i, j;
+
+	for (i = 0, j = 0; j < len; i++, j += 4)
+		output[i] = ((UINT4)input[j]) | (((UINT4)input[j + 1]) << 8) | (((UINT4)input[j + 2]) << 16) | (((UINT4)input[j + 3]) << 24);
+}
+
+static void BG_OSPAuthMemset_(void* dest, const int val, const int count)
+{
+	int i;
+	for (i = 0; i < count; ++i)
+	{
+		((unsigned char*)dest)[i] = (unsigned char)val;
+	}
+}
+
+static void BG_OSPAuthMemcpy_(void* dest, const void* src, const int count)
+{
+	int i;
+	for (i = 0; i < count; ++i)
+	{
+		((unsigned char*)dest)[i] = ((unsigned char*)src)[i];
+	}
+}
+
+
diff --git a/code/game/bg_public.h b/code/game/bg_public.h
index 6f1ecb41..d01c239b 100644
--- a/code/game/bg_public.h
+++ b/code/game/bg_public.h
@@ -752,6 +752,13 @@ void    BG_PlayerStateToEntityStateExtraPolate(playerState_t* ps, entityState_t*
 
 qboolean    BG_PlayerTouchesItem(playerState_t* ps, entityState_t* item, int atTime);
 
+//
+// bg_auth.c
+//
+void G_OSPAuthInit(void);
+void G_OSPAuthUpdateName(char* str);
+void G_OSPAuthGetSecret(char* str);
+
 
 #define ARENAS_PER_TIER     4
 #define MAX_ARENAS          1024