Hercules WPE Free

Official Packet Obfuscation Support
http://hercules.ws/board/topic/1105-hercules-wpe-free-june-14th-patch/

Signed-off-by: shennetsind <ind@henn.et>

5 files changed, 86 insertions, 9 deletions

diff --git a/src/map/battle.c b/src/map/battle.c
index f78e4f9a8..31fe502f6 100644
--- a/src/map/battle.c
+++ b/src/map/battle.c
@@ -6375,7 +6375,7 @@ static const struct _battle_data {
 	{ "cashshop_show_points",               &battle_config.cashshop_show_points,            0,      0,      1,              },
 	{ "mail_show_status",                   &battle_config.mail_show_status,                0,      0,      2,              },
 	{ "client_limit_unit_lv",               &battle_config.client_limit_unit_lv,            0,      0,      BL_ALL,         },
-// BattleGround Settings
+	// BattleGround Settings
 	{ "bg_update_interval",                 &battle_config.bg_update_interval,              1000,   100,    INT_MAX,        },
 	{ "bg_flee_penalty",                    &battle_config.bg_flee_penalty,                 20,     0,      INT_MAX,        },
 	/**
@@ -6400,6 +6400,7 @@ static const struct _battle_data {
 	{ "max_walk_path",						&battle_config.max_walk_path,					17,     1,      MAX_WALKPATH,   },
 	{ "item_enabled_npc",					&battle_config.item_enabled_npc,				1,      0,      1,				},
 	{ "gm_ignore_warpable_area",			&battle_config.gm_ignore_warpable_area,			0,		2,		100,			},
+	{ "packet_obfuscation",					&battle_config.packet_obfuscation,				1,		0,		3,				},
 };
 #ifndef STATS_OPT_OUT
 /**
@@ -6624,7 +6625,7 @@ void battle_adjust_conf(void) {
 
 #ifndef CELL_NOSTACK
 	if (battle_config.cell_stack_limit != 1)
-		ShowWarning("Battle setting 'cell_stack_limit' takes no effect as this server was compiled without Cell Stack Limit support.\n");
+		ShowWarning("Battle setting 'cell_stack_limit' takes no effect as this server was compiled without Cell Stack Limit support (CELL_NOSTACK).\n");
 #endif
 }
 
diff --git a/src/map/battle.h b/src/map/battle.h
index 02d21ed69..7d41a02c5 100644
--- a/src/map/battle.h
+++ b/src/map/battle.h
@@ -449,6 +449,7 @@ struct Battle_Config {
 	int item_restricted_consumption_type;
 	int max_walk_path;
 	int item_enabled_npc;
+	int packet_obfuscation;
 	
 	int gm_ignore_warpable_area;
 	
diff --git a/src/map/clif.c b/src/map/clif.c
index 2f8ecd6a4..2feb6f4bf 100644
--- a/src/map/clif.c
+++ b/src/map/clif.c
@@ -632,6 +632,7 @@ void clif_authfail_fd(int fd, int type)
 	WFIFOB(fd,2) = type;
 	WFIFOSET(fd,packet_len(0x81));
 	set_eof(fd);
+
 }
 
 
@@ -9288,6 +9289,7 @@ void clif_parse_WantToConnection(int fd, struct map_session_data* sd) {
 		WFIFOB(fd,2) = 3; // Rejected by server
 		WFIFOSET(fd,packet_len(0x6a));
 		set_eof(fd);
+
 		return;
 	}
 
@@ -9301,6 +9303,8 @@ void clif_parse_WantToConnection(int fd, struct map_session_data* sd) {
 
 	CREATE(sd, TBL_PC, 1);
 	sd->fd = fd;
+	sd->cryptKey = (( clif->cryptKey[0] * clif->cryptKey[1] ) + clif->cryptKey[2]) & 0xFFFFFFFF;
+	
 	session[fd]->session_data = sd;
 
 	pc->setnewpc(sd, account_id, char_id, login_id1, client_tick, sex, fd);
@@ -9819,6 +9823,7 @@ void clif_parse_QuitGame(int fd, struct map_session_data *sd)
 		(!battle_config.prevent_logout || DIFF_TICK(iTimer->gettick(), sd->canlog_tick) > battle_config.prevent_logout) )
 	{
 		set_eof(fd);
+
 		clif->disconnect_ack(sd, 0);
 	} else {
 		clif->disconnect_ack(sd, 1);
@@ -17436,6 +17441,47 @@ void clif_scriptclear(struct map_session_data *sd, int npcid) {
 	
 	clif->send(&p,sizeof(p), &sd->bl, SELF);
 }
+unsigned short clif_decrypt_cmd( int cmd, struct map_session_data *sd ) {
+	if( sd ) {
+		sd->cryptKey = (( sd->cryptKey * clif->cryptKey[1] ) + clif->cryptKey[2]) & 0xFFFFFFFF;
+		return (cmd ^ ((sd->cryptKey >> 16) & 0x7FFF));
+	}
+	return (cmd ^ (((( clif->cryptKey[0] * clif->cryptKey[1] ) + clif->cryptKey[2]) >> 16) & 0x7FFF));
+}
+unsigned short clif_parse_cmd_normal ( int fd, struct map_session_data *sd ) {
+	unsigned short cmd = RFIFOW(fd,0);
+	// filter out invalid / unsupported packets
+	if (cmd > MAX_PACKET_DB || packet_db[cmd].len == 0)
+		return 0;
+
+	return cmd;
+}
+unsigned short clif_parse_cmd_optional ( int fd, struct map_session_data *sd ) {
+	unsigned short cmd = RFIFOW(fd,0);
+
+	// filter out invalid / unsupported packets
+	if (cmd > MAX_PACKET_DB || packet_db[cmd].len == 0) {
+		cmd = clif->decrypt_cmd( cmd, sd );
+		if( cmd > MAX_PACKET_DB || packet_db[cmd].len == 0 )
+			return 0;
+		RFIFOW(fd, 0) = cmd;
+	}
+
+	return cmd;
+}
+unsigned short clif_parse_cmd_decrypt ( int fd, struct map_session_data *sd ) {
+	unsigned short cmd = RFIFOW(fd,0);
+
+	cmd = clif->decrypt_cmd( cmd, sd );
+	
+	// filter out invalid / unsupported packets
+	if (cmd > MAX_PACKET_DB || packet_db[cmd].len == 0 )
+		return 0;
+	
+	RFIFOW(fd, 0) = cmd;
+
+	return cmd;
+}
 
 /*==========================================
  * Main client packet processing function
@@ -17479,20 +17525,18 @@ int clif_parse(int fd) {
 		if (RFIFOREST(fd) < 2)
 			return 0;
 		
-		cmd = RFIFOW(fd,0);
-				
-		// filter out invalid / unsupported packets
-		if (cmd > MAX_PACKET_DB || packet_db[cmd].len == 0) {
-			ShowWarning("clif_parse: Received unsupported packet (packet 0x%04x, %d bytes received), disconnecting session #%d.\n", cmd, RFIFOREST(fd), fd);
+		if( !( cmd = clif->parse_cmd(fd,sd) ) ) {
+			ShowWarning("clif_parse: Received unsupported packet (packet 0x%04x, %d bytes received), disconnecting session #%d.\n", RFIFOW(fd,0), RFIFOREST(fd), fd);
 #ifdef DUMP_INVALID_PACKET
 			ShowDump(RFIFOP(fd,0), RFIFOREST(fd));
 #endif
 			set_eof(fd);
 			return 0;
 		}
+				
 		// determine real packet length
-		packet_len = packet_db[cmd].len;
-		if (packet_len == -1) { // variable-length packet
+		if ( ( packet_len = packet_db[cmd].len ) == -1) { // variable-length packet
+
 			if (RFIFOREST(fd) < 4)
 				return 0;
 			
@@ -17503,9 +17547,11 @@ int clif_parse(int fd) {
 				ShowDump(RFIFOP(fd,0), RFIFOREST(fd));
 #endif
 				set_eof(fd);
+
 				return 0;
 			}
 		}
+
 		if ((int)RFIFOREST(fd) < packet_len)
 			return 0; // not enough data received to form the packet
 
@@ -17598,14 +17644,29 @@ void packetdb_loaddb(void) {
 	memset(packet_db,0,sizeof(packet_db));
 	
 	#define packet(id, size, ...) packetdb_addpacket(id, size, ##__VA_ARGS__, 0xFFFF)
+	#define packetKeys(a,b,c) { clif->cryptKey[0] = a; clif->cryptKey[1] = b; clif->cryptKey[2] = c; }
 	#include "packets.h" /* load structure data */
 	#undef packet
+	#undef packetKeys
 }
 void clif_bc_ready(void) {
 	if( battle_config.display_status_timers )
 		clif->status_change = clif_status_change;
 	else
 		clif->status_change = clif_status_change_notick;
+	
+	switch( battle_config.packet_obfuscation ) {
+		case 0:
+			clif->parse_cmd = clif_parse_cmd_normal;
+			break;
+		default:
+		case 1:
+			clif->parse_cmd = clif_parse_cmd_optional;
+			break;
+		case 2:
+			clif->parse_cmd = clif_parse_cmd_decrypt;
+			break;
+	}
 }
 /*==========================================
  *
@@ -17689,6 +17750,8 @@ void clif_defaults(void) {
 	clif->send = clif_send;
 	clif->send_sub = clif_send_sub;
 	clif->parse = clif_parse;
+	clif->parse_cmd = clif_parse_cmd_optional;
+	clif->decrypt_cmd = clif_decrypt_cmd;
 	/* auth */
 	clif->authok = clif_authok;
 	clif->authrefuse = clif_authrefuse;
diff --git a/src/map/clif.h b/src/map/clif.h
index b447687ea..6e1fa81d3 100644
--- a/src/map/clif.h
+++ b/src/map/clif.h
@@ -462,6 +462,8 @@ struct clif_interface {
 		struct hCSData **data[CASHSHOP_TAB_MAX];
 		unsigned int item_count[CASHSHOP_TAB_MAX];
 	} cs;
+	/* */
+	unsigned int cryptKey[3];
 	/* core */
 	int (*init) (void);
 	void (*final) (void);
@@ -472,6 +474,8 @@ struct clif_interface {
 	int (*send) (const void* buf, int len, struct block_list* bl, enum send_target type);
 	int (*send_sub) (struct block_list *bl, va_list ap);
 	int (*parse) (int fd);
+	unsigned short (*parse_cmd) ( int fd, struct map_session_data *sd );
+	unsigned short (*decrypt_cmd) ( int cmd, struct map_session_data *sd );
 	/* auth */
 	void (*authok) (struct map_session_data *sd);
 	void (*authrefuse) (int fd, uint8 error_code);
diff --git a/src/map/packets.h b/src/map/packets.h
index aada5d53f..244f19ed8 100644
--- a/src/map/packets.h
+++ b/src/map/packets.h
@@ -10,6 +10,10 @@
 	#define packet(a,b,...)
 #endif
 
+#ifndef packetKeys
+	#define packetKeys(a,b,c)
+#endif
+
 /*
  * packet syntax
  * - packet(packet_id,length)
@@ -2017,6 +2021,8 @@ packet(0x020d,-1);
 	packet(0x08E5,41,clif->pPartyBookingRegisterReq,2,4);
 	packet(0x08d2,10);
 	packet(0x0916,26,clif->pGuildInvite2,2);
+	packetKeys(0x1540e48,0x13041224,0x31247924);
+
 #endif
 
 #ifndef PACKETVER_RE
@@ -2058,6 +2064,7 @@ packet(0x020d,-1);
 //2012-07-16aRagExe (special thanks to Yommy!)
 #if PACKETVER >= 20120716
 	packet(0x0364,8,clif->pMoveFromKafra,2,4);
+	packetKeys(0x76052205, 0x22052205, 0x22052205);
 #endif
 
 //2013-03-20Ragexe (Judas + Yommy)
@@ -2092,6 +2099,7 @@ packet(0x020d,-1);
 	packet(0x086F,26,clif->pFriendsListAdd,2);
 	packet(0x093F,5,clif->pHomMenu,2,4);
 	packet(0x0947,36,clif->pStoragePassword,0);
+	packetKeys(0x3F094C49, 0x55F86C1E, 0x58AA359A);
 	// Shuffle End
 
 	// New Packets