Allow WEBIRC from specified hosts

irc/commands.go

@@ -276,6 +276,11 @@ var Commands = map[string]Command{
 		handler:   versionHandler,
 		minParams: 0,
 	},
+	"WEBIRC": {
+		handler:      webircHandler,
+		usablePreReg: true,
+		minParams:    4,
+	},
 	"WHO": {
 		handler:   whoHandler,
 		minParams: 0,

irc/config.go

@@ -158,9 +158,10 @@ type Config struct {
 		STS                 STSConfig
 		CheckIdent          bool `yaml:"check-ident"`
 		MOTD                string
-		MOTDFormatting      bool     `yaml:"motd-formatting"`
-		ProxyAllowedFrom    []string `yaml:"proxy-allowed-from"`
-		MaxSendQString      string   `yaml:"max-sendq"`
+		MOTDFormatting      bool           `yaml:"motd-formatting"`
+		ProxyAllowedFrom    []string       `yaml:"proxy-allowed-from"`
+		WebIRC              []webircConfig `yaml:"webirc"`
+		MaxSendQString      string         `yaml:"max-sendq"`
 		MaxSendQBytes       uint64
 		ConnectionLimiter   connection_limits.LimiterConfig   `yaml:"connection-limits"`
 		ConnectionThrottler connection_limits.ThrottlerConfig `yaml:"connection-throttling"`
@@ -393,6 +394,22 @@ func LoadConfig(filename string) (config *Config, err error) {
 			return nil, fmt.Errorf("Could not parse connection-throttle ban-duration: %s", err.Error())
 		}
 	}
+	// process webirc blocks
+	var newWebIRC []webircConfig
+	for _, webirc := range config.Server.WebIRC {
+		// skip webirc blocks with no hosts (such as the example one)
+		if len(webirc.hosts) == 0 {
+			continue
+		}
+
+		err = webirc.ProcessPassword()
+		if err != nil {
+			return nil, fmt.Errorf("Could not parse WebIRC config: %s", err.Error())
+		}
+		newWebIRC = append(newWebIRC, webirc)
+	}
+	config.Server.WebIRC = newWebIRC
+	// process limits
 	if config.Limits.LineLen.Tags < 512 || config.Limits.LineLen.Rest < 512 {
 		return nil, errors.New("Line lengths must be 512 or greater (check the linelen section under server->limits)")
 	}

irc/gateways.go

@@ -0,0 +1,103 @@
+// Copyright (c) 2012-2014 Jeremy Latt
+// Copyright (c) 2014-2015 Edmund Huber
+// Copyright (c) 2017 Daniel Oaks <daniel@danieloaks.net>
+// released under the MIT license
+
+package irc
+
+import (
+	"fmt"
+	"net"
+
+	"github.com/oragono/oragono/irc/passwd"
+
+	"github.com/goshuirc/irc-go/ircmsg"
+	"github.com/oragono/oragono/irc/utils"
+)
+
+type webircConfig struct {
+	passwordString string `yaml:"password"`
+	password       []byte `yaml:"password-bytes"`
+	hosts          []string
+}
+
+// ProcessPassword populates our password.
+func (wc *webircConfig) ProcessPassword() error {
+	password, error := passwd.DecodePasswordHash(wc.passwordString)
+	wc.password = password
+	return error
+}
+
+// WEBIRC password gateway hostname ip
+func webircHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
+	// only allow unregistered clients to use this command
+	if client.registered {
+		return false
+	}
+
+	clientAddress := utils.IPString(client.socket.conn.RemoteAddr())
+	clientHostname := client.hostname
+	server.configurableStateMutex.RLock()
+	defer server.configurableStateMutex.RUnlock()
+	for _, info := range server.webirc {
+		for _, address := range info.hosts {
+			if clientHostname == address || clientAddress == address {
+				// confirm password
+				givenPassword := msg.Params[0]
+				if passwd.ComparePasswordString(info.password, givenPassword) == nil {
+					proxiedIP := msg.Params[3]
+
+					return client.ApplyProxiedIP(proxiedIP)
+				}
+			}
+		}
+	}
+
+	client.Quit("WEBIRC command is not usable from your address or incorrect password given")
+	return true
+}
+
+// PROXY TCP4/6 SOURCEIP DESTIP SOURCEPORT DESTPORT
+// http://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
+func proxyHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
+	// only allow unregistered clients to use this command
+	if client.registered {
+		return false
+	}
+
+	clientAddress := utils.IPString(client.socket.conn.RemoteAddr())
+	clientHostname := client.hostname
+	server.configurableStateMutex.RLock()
+	defer server.configurableStateMutex.RUnlock()
+	for _, address := range server.proxyAllowedFrom {
+		if clientHostname == address || clientAddress == address {
+			proxiedIP := msg.Params[1]
+
+			return client.ApplyProxiedIP(proxiedIP)
+		}
+	}
+	client.Quit("PROXY command is not usable from your address")
+	return true
+}
+
+// ApplyProxiedIP applies the given IP to the client.
+func (client *Client) ApplyProxiedIP(proxiedIP string) (exiting bool) {
+	// ensure IP is sane
+	parsedProxiedIP := net.ParseIP(proxiedIP)
+	if parsedProxiedIP == nil {
+		client.Quit(fmt.Sprintf("Proxied IP address is not valid: [%s]", proxiedIP))
+		return true
+	}
+
+	isBanned, banMsg := client.server.checkBans(parsedProxiedIP)
+	if isBanned {
+		client.Quit(banMsg)
+		return true
+	}
+
+	// given IP is sane! override the client's current IP
+	client.proxiedIP = proxiedIP
+	client.rawHostname = utils.LookupHostname(proxiedIP)
+	client.hostname = client.rawHostname
+	return false
+}

irc/help.go

@@ -460,6 +460,14 @@ Shows information about the given users. Takes up to 10 nicknames.`,
 		text: `VERSION [server]
 
 Views the version of software and the RPL_ISUPPORT tokens for the given server.`,
+	},
+	"webirc": {
+		oper: true, // not really, but it's restricted anyways
+		text: `WEBIRC <password> <gateway> <hostname> <ip>
+
+Used by web<->IRC gateways and bouncers, the WEBIRC command allows gateways to
+pass-through the real IP addresses of clients:
+ircv3.net/specs/extensions/webirc.html`,
 	},
 	"who": {
 		text: `WHO <name> [o]

irc/passwd/unsalted.go

@@ -43,3 +43,8 @@ func DecodePasswordHash(encoded string) (decoded []byte, err error) {
 func ComparePassword(hash, password []byte) error {
 	return bcrypt.CompareHashAndPassword(hash, password)
 }
+
+// ComparePasswordString compares a given password string with the given hash.
+func ComparePasswordString(hash []byte, password string) error {
+	return ComparePassword(hash, []byte(password))
+}

irc/server.go

@@ -118,6 +118,7 @@ type Server struct {
 	snomasks                     *SnoManager
 	store                        *buntdb.DB
 	stsEnabled                   bool
+	webirc                       []webircConfig
 	whoWas                       *WhoWasList
 }
 
@@ -1260,6 +1261,9 @@ func (server *Server) applyConfig(config *Config, initial bool) error {
 	}
 	server.configurableStateMutex.Unlock()
 
+	// apply new WebIRC command restrictions
+	server.webirc = config.Server.WebIRC
+
 	// apply new PROXY command restrictions
 	server.proxyAllowedFrom = config.Server.ProxyAllowedFrom
 
@@ -2158,41 +2162,3 @@ func userhostHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool
 
 	return false
 }
-
-// PROXY TCP4/6 SOURCEIP DESTIP SOURCEPORT DESTPORT
-// http://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
-func proxyHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
-	// only allow unregistered clients to use this command
-	if client.registered {
-		return false
-	}
-
-	clientAddress := utils.IPString(client.socket.conn.RemoteAddr())
-	clientHostname := client.hostname
-	for _, address := range server.proxyAllowedFrom {
-		if clientHostname == address || clientAddress == address {
-			proxiedIP := msg.Params[1]
-
-			// ensure IP is sane
-			parsedProxiedIP := net.ParseIP(proxiedIP)
-			if parsedProxiedIP == nil {
-				client.Quit(fmt.Sprintf("Proxied IP address is not valid: [%s]", proxiedIP))
-				return true
-			}
-
-			isBanned, banMsg := server.checkBans(parsedProxiedIP)
-			if isBanned {
-				client.Quit(banMsg)
-				return true
-			}
-
-			// override the client's regular IP
-			client.proxiedIP = msg.Params[1]
-			client.rawHostname = utils.LookupHostname(msg.Params[1])
-			client.hostname = client.rawHostname
-			return false
-		}
-	}
-	client.Quit("PROXY command is not usable from your address")
-	return true
-}

oragono.yaml

@@ -65,6 +65,19 @@ server:
         # - localhost
         # - "127.0.0.1"
 
+    # controls the use of the WEBIRC command (by IRC<->web interfaces, bouncers and similar)
+    webirc:
+        # one webirc block -- should correspond to one set of gateways
+        -
+            # password the gateway uses to connect, made with  oragono genpasswd
+            password: JDJhJDA0JG9rTTVERlNRa0hpOEZpNkhjZE95SU9Da1BseFdlcWtOTEQxNEFERVlqbEZNTkdhOVlYUkMu
+
+            # hosts that can use this webirc command
+            hosts:
+                # - localhost
+                # - "127.0.0.1"
+                # - "0::1"
+
     # maximum length of clients' sendQ in bytes
     # this should be big enough to hold /LIST and HELP replies
     max-sendq: 16k