sqlproxyccl: add proxy protocol listener

Resolves #117240

Release note: None

pkg/ccl/cliccl/flags.go

@@ -69,6 +69,7 @@ func init() {
 		cliflagcfg.StringFlag(f, &proxyContext.Denylist, cliflags.DenyList)
 		cliflagcfg.StringFlag(f, &proxyContext.Allowlist, cliflags.AllowList)
 		cliflagcfg.StringFlag(f, &proxyContext.ListenAddr, cliflags.ProxyListenAddr)
+		cliflagcfg.StringFlag(f, &proxyContext.ProxyProtocolListenAddr, cliflags.ProxyProtocolListenAddr)
 		cliflagcfg.StringFlag(f, &proxyContext.ListenCert, cliflags.ListenCert)
 		cliflagcfg.StringFlag(f, &proxyContext.ListenKey, cliflags.ListenKey)
 		cliflagcfg.StringFlag(f, &proxyContext.MetricsAddress, cliflags.ListenMetrics)

pkg/ccl/cliccl/mt_proxy.go

@@ -61,6 +61,14 @@ func runStartSQLProxy(cmd *cobra.Command, args []string) (returnErr error) {
 		return err
 	}
 
+	var proxyProtocolLn net.Listener
+	if proxyContext.ProxyProtocolListenAddr != "" {
+		proxyProtocolLn, err = net.Listen("tcp", proxyContext.ProxyProtocolListenAddr)
+		if err != nil {
+			return err
+		}
+	}
+
 	metricsLn, err := net.Listen("tcp", proxyContext.MetricsAddress)
 	if err != nil {
 		return err
@@ -85,13 +93,24 @@ func runStartSQLProxy(cmd *cobra.Command, args []string) (returnErr error) {
 
 	if err := stopper.RunAsyncTask(ctx, "serve-proxy", func(ctx context.Context) {
 		log.Infof(ctx, "proxy server listening at %s", proxyLn.Addr())
-		if err := server.Serve(ctx, proxyLn); err != nil {
+		if err := server.Serve(ctx, proxyLn, proxyContext.RequireProxyProtocol); err != nil {
 			errChan <- err
 		}
 	}); err != nil {
 		return err
 	}
 
+	if proxyProtocolLn != nil {
+		if err := stopper.RunAsyncTask(ctx, "serve-proxy-with-required-proxy-headers", func(ctx context.Context) {
+			log.Infof(ctx, "proxy with required proxy headers server listening at %s", proxyProtocolLn.Addr())
+			if err := server.Serve(ctx, proxyProtocolLn, true /* requireProxyProtocol */); err != nil {
+				errChan <- err
+			}
+		}); err != nil {
+			return err
+		}
+	}
+
 	return waitForSignals(ctx, server, stopper, proxyLn, errChan)
 }
 

pkg/ccl/sqlproxyccl/proxy_handler.go

@@ -73,6 +73,10 @@ type ProxyOptions struct {
 	Denylist string
 	// ListenAddr is the listen address for incoming connections.
 	ListenAddr string
+	// ProxyProtocolListenAddr is the optional listen address for incoming
+	// connections for which it will be enforced that the connections have proxy
+	// headers set.
+	ProxyProtocolListenAddr string
 	// ListenCert is the file containing PEM-encoded x509 certificate for listen
 	// address. Set to "*" to auto-generate self-signed cert.
 	ListenCert string
@@ -113,8 +117,10 @@ type ProxyOptions struct {
 	DisableConnectionRebalancing bool
 	// RequireProxyProtocol changes the server's behavior to support the PROXY
 	// protocol (SQL=required, HTTP=best-effort). With this set to true, the
-	// PROXY info from upstream will be trusted on both HTTP and SQL, if the
-	// headers are allowed.
+	// PROXY info from upstream will be trusted on both HTTP and SQL (on the
+	// ListenAddr port), if the headers are allowed. The ProxyProtocolListenAddr
+	// port, if specified, will require the proxy protocol regardless of
+	// RequireProxyProtocol.
 	RequireProxyProtocol bool
 
 	// testingKnobs are knobs used for testing.

pkg/ccl/sqlproxyccl/server.go

@@ -216,8 +216,8 @@ func (s *Server) ServeHTTP(ctx context.Context, ln net.Listener) error {
 // Serve serves a listener according to the Options given in NewServer().
 // Incoming client connections are taken through the Postgres handshake and
 // relayed to the configured backend server.
-func (s *Server) Serve(ctx context.Context, ln net.Listener) error {
-	if s.handler.RequireProxyProtocol {
+func (s *Server) Serve(ctx context.Context, ln net.Listener, requireProxyProtocol bool) error {
+	if requireProxyProtocol {
 		ln = &proxyproto.Listener{
 			Listener: ln,
 			Policy: func(upstream net.Addr) (proxyproto.Policy, error) {

pkg/cli/cliflags/flags_mt.go

@@ -47,6 +47,11 @@ wait for the tenant id to be fully written to the file (with a newline character
 		Description: "Listen address for incoming connections.",
 	}
 
+	ProxyProtocolListenAddr = FlagInfo{
+		Name:        "proxy-protocol-listen-addr",
+		Description: "Listen address for incoming connections which require proxy protocol headers.",
+	}
+
 	ThrottleBaseDelay = FlagInfo{
 		Name:        "throttle-base-delay",
 		Description: "Initial value for the exponential backoff used to throttle connection attempts.",