Partial damage cheat fix: node damages server side (#4981)

* Damage cheat fix: server side

* Lava/Node damages overtime server side
* lava hurt interval is only for old protocol

3 files changed, 48 insertions, 29 deletions

diff --git a/src/clientenvironment.cpp b/src/clientenvironment.cpp
index 94c8e0dcb..4a8bbb066 100644
--- a/src/clientenvironment.cpp
+++ b/src/clientenvironment.cpp
@@ -252,37 +252,31 @@ void ClientEnvironment::step(float dtime)
 		m_script->environment_step(dtime);
 	}
 
-	/*
-		A quick draft of lava damage
-	*/
-	if(m_lava_hurt_interval.step(dtime, 1.0))
-	{
-		v3f pf = lplayer->getPosition();
-
-		// Feet, middle and head
-		v3s16 p1 = floatToInt(pf + v3f(0, BS*0.1, 0), BS);
-		MapNode n1 = m_map->getNodeNoEx(p1);
-		v3s16 p2 = floatToInt(pf + v3f(0, BS*0.8, 0), BS);
-		MapNode n2 = m_map->getNodeNoEx(p2);
-		v3s16 p3 = floatToInt(pf + v3f(0, BS*1.6, 0), BS);
-		MapNode n3 = m_map->getNodeNoEx(p3);
-
-		u32 damage_per_second = 0;
-		damage_per_second = MYMAX(damage_per_second,
-			m_client->ndef()->get(n1).damage_per_second);
-		damage_per_second = MYMAX(damage_per_second,
-			m_client->ndef()->get(n2).damage_per_second);
-		damage_per_second = MYMAX(damage_per_second,
-			m_client->ndef()->get(n3).damage_per_second);
-
-		if(damage_per_second != 0)
-		{
-			damageLocalPlayer(damage_per_second, true);
-		}
-	}
-
 	// Protocol v29 make this behaviour obsolete
 	if (getGameDef()->getProtoVersion() < 29) {
+		if (m_lava_hurt_interval.step(dtime, 1.0)) {
+			v3f pf = lplayer->getPosition();
+
+			// Feet, middle and head
+			v3s16 p1 = floatToInt(pf + v3f(0, BS * 0.1, 0), BS);
+			MapNode n1 = m_map->getNodeNoEx(p1);
+			v3s16 p2 = floatToInt(pf + v3f(0, BS * 0.8, 0), BS);
+			MapNode n2 = m_map->getNodeNoEx(p2);
+			v3s16 p3 = floatToInt(pf + v3f(0, BS * 1.6, 0), BS);
+			MapNode n3 = m_map->getNodeNoEx(p3);
+
+			u32 damage_per_second = 0;
+			damage_per_second = MYMAX(damage_per_second,
+				m_client->ndef()->get(n1).damage_per_second);
+			damage_per_second = MYMAX(damage_per_second,
+				m_client->ndef()->get(n2).damage_per_second);
+			damage_per_second = MYMAX(damage_per_second,
+				m_client->ndef()->get(n3).damage_per_second);
+
+			if (damage_per_second != 0)
+				damageLocalPlayer(damage_per_second, true);
+		}
+
 		/*
 			Drowning
 		*/
diff --git a/src/content_sao.cpp b/src/content_sao.cpp
index 282a6546c..bb2387d1a 100644
--- a/src/content_sao.cpp
+++ b/src/content_sao.cpp
@@ -941,6 +941,30 @@ void PlayerSAO::step(float dtime, bool send_recommended)
 			setBreath(m_breath + 1);
 	}
 
+	if (m_node_hurt_interval.step(dtime, 1.0)) {
+		// Feet, middle and head
+		v3s16 p1 = floatToInt(m_base_position + v3f(0, BS*0.1, 0), BS);
+		MapNode n1 = m_env->getMap().getNodeNoEx(p1);
+		v3s16 p2 = floatToInt(m_base_position + v3f(0, BS*0.8, 0), BS);
+		MapNode n2 = m_env->getMap().getNodeNoEx(p2);
+		v3s16 p3 = floatToInt(m_base_position + v3f(0, BS*1.6, 0), BS);
+		MapNode n3 = m_env->getMap().getNodeNoEx(p3);
+
+		u32 damage_per_second = 0;
+		damage_per_second = MYMAX(damage_per_second,
+			m_env->getGameDef()->ndef()->get(n1).damage_per_second);
+		damage_per_second = MYMAX(damage_per_second,
+			m_env->getGameDef()->ndef()->get(n2).damage_per_second);
+		damage_per_second = MYMAX(damage_per_second,
+			m_env->getGameDef()->ndef()->get(n3).damage_per_second);
+
+		if (damage_per_second != 0 && m_hp > 0) {
+			s16 newhp = ((s32) damage_per_second > m_hp ? 0 : m_hp - damage_per_second);
+			setHP(newhp);
+			m_env->getGameDef()->SendPlayerHPOrDie(this);
+		}
+	}
+
 	if (!m_properties_sent) {
 		m_properties_sent = true;
 		std::string str = getPropertyPacket();
diff --git a/src/content_sao.h b/src/content_sao.h
index 918830266..c1b01b6dd 100644
--- a/src/content_sao.h
+++ b/src/content_sao.h
@@ -375,6 +375,7 @@ private:
 	// Timers
 	IntervalLimiter m_breathing_interval;
 	IntervalLimiter m_drowning_interval;
+	IntervalLimiter m_node_hurt_interval;
 
 	int m_wield_index;
 	bool m_position_not_sent;