rejection http-response, ca certs

O-X-L · Oct 1, 2023 · 51d67a4 · 51d67a4
1 parent f21c825
commit 51d67a4
Show file tree

Hide file tree

Showing 12 changed files with 329 additions and 40 deletions.
diff --git a/config_example.yml b/config_example.yml
@@ -11,14 +11,15 @@ service:
       tproxy: false
     - mode: 'proxyproto'
       port: 4129
-    # - mode: 'http'  # not yet implemented
-    #   port: 4130
-    # - mode: 'https'  # not yet implemented
-    #   port: 4131
+    - mode: 'http'
+      port: 4130
+    - mode: 'https'  # not yet implemented
+      port: 4131
     # - mode: 'socks5'  # not yet implemented
     #   port: 4132
 
   certs:
+    caPublic: '/tmp/calamary.ca.crt'
     serverPublic: '/tmp/calamary.crt'
     serverPrivate: '/tmp/calamary.key'
     interceptPublic: '/tmp/calamary.subca.crt'

diff --git a/docs/source/info/modes.rst b/docs/source/info/modes.rst
@@ -0,0 +1,199 @@
+.. _modes:
+
+.. include:: ../_inc/head.rst
+
+.. include:: ../_inc/in_progress.rst
+
+#####
+Modes
+#####
+
+Transparent
+###########
+
+Behaviour
+=========
+
+DNAT - TCP (plaintext)
+----------------------
+
+**Server**
+
+.. code-block:: bash
+
+    2023-10-01 23:43:01 | INFO | 192.168.11.104 => 135.181.170.219:80 | Accept
+
+
+**Client**
+
+.. code-block:: bash
+
+    curl http://superstes.eu -v
+    *   Trying 135.181.170.219:80...
+    * Connected to superstes.eu (135.181.170.219) port 80 (#0)
+    > GET / HTTP/1.1
+    > Host: superstes.eu
+    ...
+    < 
+    <html>
+    <head><title>301 Moved Permanently</title></head>
+    <body>
+    <center><h1>301 Moved Permanently</h1></center>
+    <hr><center>nginx</center>
+    </body>
+    </html>
+    * Connection #0 to host superstes.eu left intact
+
+
+DNAT - TLS
+----------
+
+**Server**
+
+.. code-block:: bash
+
+    2023-10-01 23:43:09 | INFO | 192.168.11.104 => 135.181.170.219:443 | Accept
+
+
+**Client**
+
+.. code-block:: bash
+
+    host@calamary$ curl https://superstes.eu -v
+
+    *   Trying 135.181.170.219:443...
+    * Connected to superstes.eu (135.181.170.219) port 443 (#0)
+    ...
+    < HTTP/2 302 
+    < server: nginx
+    ...
+    < 
+    <html>
+    <head><title>302 Found</title></head>
+    <body>
+    <center><h1>302 Found</h1></center>
+    <hr><center>nginx</center>
+    </body>
+    </html>
+    * Connection #0 to host superstes.eu left intact
+
+
+HTTP Proxy
+##########
+
+Behaviour
+=========
+
+HTTP
+----
+
+**Server**
+
+.. code-block:: bash
+
+    2023-10-01 23:40:34 | INFO | 127.0.0.1 => 135.181.170.219:80 | Accept
+
+
+**Client**
+
+.. code-block:: bash
+
+    host@calamary$ http_proxy=http://localhost:4130 curl http://superstes.eu -v
+
+    * Uses proxy env variable http_proxy == 'http://localhost:4130'
+    *   Trying 127.0.0.1:4130...
+    * Connected to (nil) (127.0.0.1) port 4130 (#0)
+    > GET http://superstes.eu/ HTTP/1.1
+    > Host: superstes.eu
+    > User-Agent: curl/7.81.0
+    > Accept: */*
+    > Proxy-Connection: Keep-Alive
+    > 
+    ...
+    < 
+    <html>
+    <head><title>301 Moved Permanently</title></head>
+    <body>
+    <center><h1>301 Moved Permanently</h1></center>
+    <hr><center>nginx</center>
+    </body>
+    </html>
+    * Connection #0 to host (nil) left intact
+
+HTTPS
+-----
+
+**Server**
+
+.. code-block:: bash
+
+    2023-10-01 23:40:43 | INFO | 127.0.0.1 => 135.181.170.219:443 | Accept
+
+
+**Client**
+
+.. code-block:: bash
+
+    host@calamary$ https_proxy=http://localhost:4130 curl https://superstes.eu -v
+
+    * Uses proxy env variable https_proxy == 'http://localhost:4130'
+    *   Trying 127.0.0.1:4130...
+    * Connected to (nil) (127.0.0.1) port 4130 (#0)
+    * allocate connect buffer!
+    * Establish HTTP proxy tunnel to superstes.eu:443
+    > CONNECT superstes.eu:443 HTTP/1.1
+    > Host: superstes.eu:443
+    > User-Agent: curl/7.81.0
+    > Proxy-Connection: Keep-Alive
+    > 
+    < HTTP/1.1 200 OK
+    < Content-Length: 0
+    * Ignoring Content-Length in CONNECT 200 response
+    < 
+    * Proxy replied 200 to CONNECT request
+    * CONNECT phase completed!
+    ...
+    > GET / HTTP/2
+    > Host: superstes.eu
+    > user-agent: curl/7.81.0
+    > accept: */*
+    > 
+    ...
+    < HTTP/2 302 
+    < server: nginx
+    ...
+    < 
+    * TLSv1.2 (IN), TLS header, Supplemental data (23):
+    <html>
+    <head><title>302 Found</title></head>
+    <body>
+    <center><h1>302 Found</h1></center>
+    <hr><center>nginx</center>
+    </body>
+    </html>
+    * Connection #0 to host (nil) left intact
+
+
+HTTPS Proxy
+###########
+
+Behaviour
+=========
+
+tbd
+
+Proxy Protocol
+##############
+
+Behaviour
+=========
+
+tbd
+
+SOCKS5
+######
+
+Behaviour
+=========
+
+tbd
diff --git a/docs/source/info/rules.rst b/docs/source/info/rules.rst
@@ -39,6 +39,8 @@ Multiple matches can be defined in a single rule.
 
 The value of matches is **case-insensitive** by default.
 
+NOTE: The HTTP host-header domain is not compared if :code:`dns` is used - as it can be modified easily.
+
 You can define **multiple values** for each match.
 
 Matches can also be **negated** by using the :code:`!` prefix:

diff --git a/lib/cnf/cnf_file/validate.go b/lib/cnf/cnf_file/validate.go
@@ -45,6 +45,11 @@ func validateListener(lncnf cnf.ServiceListener, fail bool) bool {
 }
 
 func validateCerts(certs cnf.ServiceCertificates, fail bool) bool {
+	if certs.CAPublic != "" {
+		if !validateCert(certs.CAPublic, true, fail) {
+			return false
+		}
+	}
 	if certs.ServerPublic != "" || certs.ServerPrivate != "" {
 		if !validateCert(certs.ServerPublic, true, fail) {
 			return false

diff --git a/lib/cnf/config.go b/lib/cnf/config.go
@@ -64,6 +64,7 @@ type ServiceMetrics struct {
 }
 
 type ServiceCertificates struct {
+	CAPublic         string `yaml:"caPublic"`
 	ServerPublic     string `yaml:"serverPublic"`
 	ServerPrivate    string `yaml:"serverPrivate"`
 	InterceptPublic  string `yaml:"interceptPublic"`

diff --git a/lib/main/service.go b/lib/main/service.go
@@ -59,11 +59,6 @@ func (svc *service) shutdown(cancel context.CancelFunc) {
 	}
 	log.Info("service", "Stopped")
 	os.Exit(0)
-	/*
-		ctx := context.Background()
-		doneHTTP := httpserver.Shutdown(ctx)
-		<-doneHTTP
-	*/
 }
 
 func (svc *service) serve(srv rcv.Server) (err error) {

diff --git a/lib/proc/fwd/http.go b/lib/proc/fwd/http.go
@@ -31,21 +31,25 @@ func ForwardHttp(srvCnf cnf.ServiceListener, l4Proto meta.Proto, conn net.Conn)
 	}
 
 	// todo: full parsing may not be needed if 'connect'
-	pktProxy, connProxyIo := parseConn(srvCnf, l4Proto, conn)
+	pktProxy, connProxyIo, err := parseConn(srvCnf, l4Proto, conn)
+	if err != nil {
+		return
+	}
 
 	if pktProxy.L5.Proto != meta.ProtoL5Http {
 		parse.LogConnError("forward", pktProxy, "Got non HTTP-Request on HTTP server")
 		return
 	}
 
 	reqProxy := readRequest(pktProxy, connProxyIo)
-
 	if reqProxy == nil {
 		return
+
 	} else if reqProxy.Method == http.MethodConnect {
 		forwardConnect(srvCnf, l4Proto, conn, pktProxy, connProxyIo, reqProxy)
+
 	} else {
-		// plaintext HTTP is unsafe by design and should not be allowed
+		// plaintext HTTP is unsecure by design and should not be allowed
 		// todo: implement generic https-redirection response
 
 		forwardPlain(srvCnf, l4Proto, conn, pktProxy, connProxyIo, reqProxy)
@@ -67,7 +71,11 @@ func forwardPlain(
 	pkt.L3.DestIP = dest
 	parse.LogConnDebug("forward", pkt, "Updated destination IP")
 
-	filterConn(pkt, conn, connIo)
+	if !filterConn(pkt, conn, connIo) {
+		proxyResp := responseReject()
+		proxyResp.Write(conn)
+		return
+	}
 	send.ForwardHttp(pkt, conn, connIo, req)
 }
 
@@ -87,7 +95,11 @@ func forwardConnect(
 		return
 	}
 
-	pkt, connIo := parseConn(srvCnf, l4Proto, conn)
+	pkt, connIo, err := parseConn(srvCnf, l4Proto, conn)
+	if err != nil {
+		return
+	}
+
 	host, port := parse.SplitHttpHost(reqProxy.Host, pkt.L5.Encrypted)
 	pkt.L5Http = &parse.ParsedHttp{
 		Host: host,
@@ -108,9 +120,18 @@ func forwardConnect(
 	pkt.L3.DestIP = dest
 	parse.LogConnDebug("forward", pkt, "Updated destination IP")
 
-	filterConn(pkt, conn, connIo)
-	send.Forward(pkt, conn, connIo)
+	if !filterConn(pkt, conn, connIo) {
+		if pkt.L5.Encrypted == meta.OptBoolTrue {
+			// http response for https will show a cryptic response ('wrong version number' vs 'eof while reading')
+			return
 
+		} else {
+			proxyResp := responseReject()
+			proxyResp.Write(conn)
+			return
+		}
+	}
+	send.Forward(pkt, conn, connIo)
 }
 
 func resolveTargetHostname(pkt parse.ParsedPacket) net.IP {
@@ -150,6 +171,14 @@ func responseFailed() http.Response {
 	}
 }
 
+func responseReject() http.Response {
+	return http.Response{
+		StatusCode: http.StatusForbidden,
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+	}
+}
+
 func readRequest(pkt parse.ParsedPacket, connIo io.ReadWriter) *http.Request {
 	reqRaw := bufio.NewReader(connIo)
 	req, err := http.ReadRequest(reqRaw)

diff --git a/lib/proc/fwd/main.go b/lib/proc/fwd/main.go
@@ -23,30 +23,39 @@ func Forward(srvCnf cnf.ServiceListener, l4Proto meta.Proto, conn net.Conn) {
 		defer metrics.CurrentConn.Dec()
 	}
 
-	pkt, connIo := parseConn(srvCnf, l4Proto, conn)
-	filterConn(pkt, conn, connIo)
+	pkt, connIo, err := parseConn(srvCnf, l4Proto, conn)
+	if err != nil {
+		return
+	}
+	if !filterConn(pkt, conn, connIo) {
+		return
+	}
 	send.Forward(pkt, conn, connIo)
 }
 
-func parseConn(srvCnf cnf.ServiceListener, l4Proto meta.Proto, conn net.Conn) (pkt parse.ParsedPacket, connIo io.ReadWriter) {
+func parseConn(srvCnf cnf.ServiceListener, l4Proto meta.Proto, conn net.Conn) (pkt parse.ParsedPacket, connIo io.ReadWriter, err error) {
 	connIo = conn
 	connIoBuf := new(bytes.Buffer)
 	connIoTee := io.TeeReader(connIo, connIoBuf)
 
-	pkt = parse.Parse(srvCnf, l4Proto, conn, connIoTee)
+	pkt, err = parse.Parse(srvCnf, l4Proto, conn, connIoTee)
+
+	if err != nil {
+		return
+	}
 
 	// write read bytes back to stream so we can forward them
 	connIo = u.NewReadWriter(io.MultiReader(bytes.NewReader(connIoBuf.Bytes()), connIo), connIo)
 
 	return
 }
 
-func filterConn(pkt parse.ParsedPacket, conn net.Conn, connIo io.ReadWriter) {
+func filterConn(pkt parse.ParsedPacket, conn net.Conn, connIo io.ReadWriter) bool {
 	if !filter.Filter(pkt) {
 		parse.LogConnInfo("forward", pkt, "Denied")
-		conn.Close()
-		return
+		return false
 	}
 
 	parse.LogConnInfo("forward", pkt, "Accept")
+	return true
 }