pass the correct quit message when a proxied client is banned

If you were banned and the ban was only detected when you proxied
(because you were proxying from a DLINE'd IP), you'd get an incorrect
quit message: `QUIT: Bad or unauthorized PROXY command`. This propagates
the correct ban message as the quit line.

irc/errors.go

@@ -13,7 +13,6 @@ var (
 	errAccountAlreadyVerified         = errors.New(`Account is already verified`)
 	errAccountCantDropPrimaryNick     = errors.New("Can't unreserve primary nickname")
 	errAccountCreation                = errors.New("Account could not be created")
-	errAccountCredUpdate              = errors.New("Could not update password hash to new method")
 	errAccountDoesNotExist            = errors.New("Account does not exist")
 	errAccountInvalidCredentials      = errors.New("Invalid account credentials")
 	errAccountBadPassphrase           = errors.New(`Passphrase contains forbidden characters or is otherwise invalid`)
@@ -28,7 +27,6 @@ var (
 	errCallbackFailed                 = errors.New("Account verification could not be sent")
 	errCertfpAlreadyExists            = errors.New(`An account already exists for your certificate fingerprint`)
 	errChannelNotOwnedByAccount       = errors.New("Channel not owned by the specified account")
-	errChannelDoesNotExist            = errors.New("Channel does not exist")
 	errChannelAlreadyRegistered       = errors.New("Channel is already registered")
 	errChannelNameInUse               = errors.New(`Channel name in use`)
 	errInvalidChannelName             = errors.New(`Invalid channel name`)
@@ -38,12 +36,10 @@ var (
 	errNicknameReserved               = errors.New("nickname is reserved")
 	errNoExistingBan                  = errors.New("Ban does not exist")
 	errNoSuchChannel                  = errors.New(`No such channel`)
-	errRenamePrivsNeeded              = errors.New(`Only chanops can rename channels`)
 	errInsufficientPrivs              = errors.New("Insufficient privileges")
-	errSaslFail                       = errors.New("SASL failed")
-	errResumeTokenAlreadySet          = errors.New("Client was already assigned a resume token")
 	errInvalidUsername                = errors.New("Invalid username")
 	errFeatureDisabled                = errors.New(`That feature is disabled`)
+	errBanned                         = errors.New("IP or nickmask banned")
 	errInvalidParams                  = errors.New("Invalid parameters")
 )
 

irc/gateways.go

@@ -46,24 +46,22 @@ func (wc *webircConfig) Populate() (err error) {
 }
 
 // ApplyProxiedIP applies the given IP to the client.
-func (client *Client) ApplyProxiedIP(session *Session, proxiedIP string, tls bool) (success bool) {
+func (client *Client) ApplyProxiedIP(session *Session, proxiedIP string, tls bool) (err error, quitMsg string) {
 	// PROXY and WEBIRC are never accepted from a Tor listener, even if the address itself
 	// is whitelisted:
 	if client.isTor {
-		return false
+		return errBadProxyLine, ""
 	}
 
 	// ensure IP is sane
 	parsedProxiedIP := net.ParseIP(proxiedIP).To16()
 	if parsedProxiedIP == nil {
-		client.Quit(fmt.Sprintf(client.t("Proxied IP address is not valid: [%s]"), proxiedIP), session)
+		return errBadProxyLine, fmt.Sprintf(client.t("Proxied IP address is not valid: [%s]"), proxiedIP)
-		return false
 	}
 
 	isBanned, banMsg := client.server.checkBans(parsedProxiedIP)
 	if isBanned {
-		client.Quit(banMsg, session)
+		return errBanned, banMsg
-		return false
 	}
 
 	// given IP is sane! override the client's current IP
@@ -84,7 +82,7 @@ func (client *Client) ApplyProxiedIP(session *Session, proxiedIP string, tls boo
 	client.certfp = ""
 	client.SetMode(modes.TLS, tls)
 
-	return true
+	return nil, ""
 }
 
 // handle the PROXY command: http://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
@@ -93,9 +91,13 @@ func (client *Client) ApplyProxiedIP(session *Session, proxiedIP string, tls boo
 // unfortunately, an ipv6 SOURCEIP can start with a double colon; in this case,
 // the message is invalid IRC and can't be parsed normally, hence the special handling.
 func handleProxyCommand(server *Server, client *Client, session *Session, line string) (err error) {
+	var quitMsg string
 	defer func() {
 		if err != nil {
-			client.Quit(client.t("Bad or unauthorized PROXY command"), session)
+			if quitMsg == "" {
+				quitMsg = client.t("Bad or unauthorized PROXY command")
+			}
+			client.Quit(quitMsg, session)
 		}
 	}()
 
@@ -106,13 +108,10 @@ func handleProxyCommand(server *Server, client *Client, session *Session, line s
 
 	if utils.IPInNets(client.realIP, server.Config().Server.proxyAllowedFromNets) {
 		// assume PROXY connections are always secure
-		if client.ApplyProxiedIP(session, params[2], true) {
+		err, quitMsg = client.ApplyProxiedIP(session, params[2], true)
-			return nil
+		return
-		} else {
+	} else {
-			return errBadProxyLine
+		// real source IP is not authorized to issue PROXY:
-		}
+		return errBadGatewayAddress
 	}
-
-	// real source IP is not authorized to issue PROXY:
-	return errBadGatewayAddress
 }

irc/handlers.go

@@ -2576,7 +2576,13 @@ func webircHandler(server *Server, client *Client, msg ircmsg.IrcMessage, rb *Re
 			if strings.HasPrefix(proxiedIP, "[") && strings.HasSuffix(proxiedIP, "]") {
 				proxiedIP = proxiedIP[1 : len(proxiedIP)-1]
 			}
-			return !client.ApplyProxiedIP(rb.session, proxiedIP, secure)
+			err, quitMsg := client.ApplyProxiedIP(rb.session, proxiedIP, secure)
+			if err != nil {
+				client.Quit(quitMsg, rb.session)
+				return true
+			} else {
+				return false
+			}
 		}
 	}