From ebb9d629d75c59dc2e36de5fda6b0c985ae5dc44 Mon Sep 17 00:00:00 2001
From: Daniel Oaks <daniel@danieloaks.net>
Date: Wed, 24 May 2017 00:58:36 -0600
Subject: [PATCH] xline: Add ANDKILL param to kill all matching clients

---
 irc/client.go |  7 ++++++-
 irc/dline.go  | 45 +++++++++++++++++++++++++++++++++++++++++----
 irc/help.go   |  8 ++++++--
 irc/kline.go  | 36 ++++++++++++++++++++++++++++++++++--
 irc/server.go |  2 +-
 5 files changed, 88 insertions(+), 10 deletions(-)

diff --git a/irc/client.go b/irc/client.go
index 079a049a..89d7de56 100644
--- a/irc/client.go
+++ b/irc/client.go
@@ -137,6 +137,11 @@ func NewClient(server *Server, conn net.Conn, isTLS bool) *Client {
 	return client
 }
 
+// IP returns the IP address of this client.
+func (client *Client) IP() net.IP {
+	return net.ParseIP(IPString(client.socket.conn.RemoteAddr()))
+}
+
 //
 // command goroutine
 //
@@ -475,7 +480,7 @@ func (client *Client) destroy() {
 	friends.Remove(client)
 
 	// remove from connection limits
-	ipaddr := net.ParseIP(IPString(client.socket.conn.RemoteAddr()))
+	ipaddr := client.IP()
 	// this check shouldn't be required but eh
 	if ipaddr != nil {
 		client.server.connectionLimitsMutex.Lock()
diff --git a/irc/dline.go b/irc/dline.go
index 1b37156a..13e72793 100644
--- a/irc/dline.go
+++ b/irc/dline.go
@@ -183,7 +183,7 @@ func (dm *DLineManager) CheckIP(addr net.IP) (isBanned bool, info *IPBanInfo) {
 	return false, nil
 }
 
-// DLINE [MYSELF] [duration] <ip>/<net> [ON <server>] [reason [| oper reason]]
+// DLINE [ANDKILL] [MYSELF] [duration] <ip>/<net> [ON <server>] [reason [| oper reason]]
 func dlineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 	// check oper permissions
 	if !client.class.Capabilities["oper:local_ban"] {
@@ -193,6 +193,13 @@ func dlineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 
 	currentArg := 0
 
+	// when setting a ban, if they say "ANDKILL" we should also kill all users who match it
+	var andKill bool
+	if len(msg.Params) > currentArg+1 && strings.ToLower(msg.Params[currentArg]) == "andkill" {
+		andKill = true
+		currentArg++
+	}
+
 	// when setting a ban that covers the oper's current connection, we require them to say
 	// "DLINE MYSELF" so that we're sure they really mean it.
 	var dlineMyself bool
@@ -232,13 +239,13 @@ func dlineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 
 	if hostNet == nil {
 		hostString = hostAddr.String()
-		if !dlineMyself && hostAddr.Equal(net.ParseIP(IPString(client.socket.conn.RemoteAddr()))) {
+		if !dlineMyself && hostAddr.Equal(client.IP()) {
 			client.Send(nil, server.name, ERR_UNKNOWNERROR, client.nick, msg.Command, "This ban matches you. To DLINE yourself, you must use the command:  /DLINE MYSELF <arguments>")
 			return false
 		}
 	} else {
 		hostString = hostNet.String()
-		if !dlineMyself && hostNet.Contains(net.ParseIP(IPString(client.socket.conn.RemoteAddr()))) {
+		if !dlineMyself && hostNet.Contains(client.IP()) {
 			client.Send(nil, server.name, ERR_UNKNOWNERROR, client.nick, msg.Command, "This ban matches you. To DLINE yourself, you must use the command:  /DLINE MYSELF <arguments>")
 			return false
 		}
@@ -315,7 +322,37 @@ func dlineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 		client.Notice(fmt.Sprintf("Added D-Line for %s", hostString))
 	}
 
-	return false
+	var killClient bool
+	if andKill {
+		var clientsToKill []*Client
+		var toKill bool
+
+		server.clients.ByNickMutex.RLock()
+		for _, mcl := range server.clients.ByNick {
+			if hostNet == nil {
+				toKill = hostAddr.Equal(mcl.IP())
+			} else {
+				toKill = hostNet.Contains(mcl.IP())
+			}
+
+			if toKill {
+				clientsToKill = append(clientsToKill, mcl)
+			}
+		}
+		server.clients.ByNickMutex.RUnlock()
+
+		for _, mcl := range clientsToKill {
+			mcl.Quit(fmt.Sprintf("You have been banned from this server (%s)", reason))
+			if mcl == client {
+				killClient = true
+			} else {
+				// if mcl == client, we kill them below
+				mcl.destroy()
+			}
+		}
+	}
+
+	return killClient
 }
 
 func unDLineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
diff --git a/irc/help.go b/irc/help.go
index 92fbca16..fc44d8c5 100644
--- a/irc/help.go
+++ b/irc/help.go
@@ -145,7 +145,7 @@ Prints debug information about the IRCd. <option> can be one of:
 	},
 	"dline": {
 		oper: true,
-		text: `DLINE [MYSELF] [duration] <ip>/<net> [ON <server>] [reason [| oper reason]]
+		text: `DLINE [ANDKILL] [MYSELF] [duration] <ip>/<net> [ON <server>] [reason [| oper reason]]
 
 Bans an IP address or network from connecting to the server. If the duration is
 given then only for that long. The reason is shown to the user themselves, but
@@ -154,6 +154,8 @@ operators getting info about the DLINEs that exist.
 
 Bans are saved across subsequent launches of the server.
 
+"ANDKILL" means that all matching clients are also removed from the server.
+
 "MYSELF" is required when the DLINE matches the address the person applying it is connected
 from. If "MYSELF" is not given, trying to DLINE yourself will result in an error.
 
@@ -211,7 +213,7 @@ supplied.`,
 	},
 	"kline": {
 		oper: true,
-		text: `KLINE [MYSELF] [duration] <mask> [ON <server>] [reason [| oper reason]]
+		text: `KLINE [ANDKILL] [MYSELF] [duration] <mask> [ON <server>] [reason [| oper reason]]
 
 Bans a mask from connecting to the server. If the duration is given then only for that
 long. The reason is shown to the user themselves, but everyone else will see a standard
@@ -219,6 +221,8 @@ message. The oper reason is shown to operators getting info about the KLINEs tha
 
 Bans are saved across subsequent launches of the server.
 
+"ANDKILL" means that all matching clients are also removed from the server.
+
 "MYSELF" is required when the KLINE matches the address the person applying it is connected
 from. If "MYSELF" is not given, trying to KLINE yourself will result in an error.
 
diff --git a/irc/kline.go b/irc/kline.go
index 455c89ae..c3e5f2c1 100644
--- a/irc/kline.go
+++ b/irc/kline.go
@@ -110,7 +110,7 @@ func (km *KLineManager) CheckMasks(masks ...string) (isBanned bool, info *IPBanI
 	return false, nil
 }
 
-// KLINE [MYSELF] [duration] <mask> [ON <server>] [reason [| oper reason]]
+// KLINE [ANDKILL] [MYSELF] [duration] <mask> [ON <server>] [reason [| oper reason]]
 func klineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 	// check oper permissions
 	if !client.class.Capabilities["oper:local_ban"] {
@@ -120,6 +120,13 @@ func klineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 
 	currentArg := 0
 
+	// when setting a ban, if they say "ANDKILL" we should also kill all users who match it
+	var andKill bool
+	if len(msg.Params) > currentArg+1 && strings.ToLower(msg.Params[currentArg]) == "andkill" {
+		andKill = true
+		currentArg++
+	}
+
 	// when setting a ban that covers the oper's current connection, we require them to say
 	// "KLINE MYSELF" so that we're sure they really mean it.
 	var klineMyself bool
@@ -226,7 +233,32 @@ func klineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
 		client.Notice(fmt.Sprintf("Added K-Line for %s", mask))
 	}
 
-	return false
+	var killClient bool
+	if andKill {
+		var clientsToKill []*Client
+
+		server.clients.ByNickMutex.RLock()
+		for _, mcl := range server.clients.ByNick {
+			for _, clientMask := range mcl.AllNickmasks() {
+				if matcher.Match(clientMask) {
+					clientsToKill = append(clientsToKill, mcl)
+				}
+			}
+		}
+		server.clients.ByNickMutex.RUnlock()
+
+		for _, mcl := range clientsToKill {
+			mcl.Quit(fmt.Sprintf("You have been banned from this server (%s)", reason))
+			if mcl == client {
+				killClient = true
+			} else {
+				// if mcl == client, we kill them below
+				mcl.destroy()
+			}
+		}
+	}
+
+	return killClient
 }
 
 func unKLineHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
diff --git a/irc/server.go b/irc/server.go
index 9079f9cb..bac2bfd9 100644
--- a/irc/server.go
+++ b/irc/server.go
@@ -1358,7 +1358,7 @@ func (server *Server) rehash() error {
 
 	server.clients.ByNickMutex.RLock()
 	for _, client := range server.clients.ByNick {
-		ipaddr := net.ParseIP(IPString(client.socket.conn.RemoteAddr()))
+		ipaddr := client.IP()
 		if ipaddr != nil {
 			server.connectionLimits.AddClient(ipaddr, true)
 		}