From 3159ffe3ebe32a628a61e94951868dc05b2d600a Mon Sep 17 00:00:00 2001
From: xdrm-brackets <doowap31@gmail.com>
Date: Wed, 25 Apr 2018 17:01:39 +0200
Subject: [PATCH] moved header checks/extracts into single file + added
 'checkOriginPolicy' (Host/Origin headers can be read in any order) + added
 key check+extraction

---
 http/upgrade/request/header_check.go | 130 +++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)
 create mode 100644 http/upgrade/request/header_check.go

diff --git a/http/upgrade/request/header_check.go b/http/upgrade/request/header_check.go
new file mode 100644
index 0000000..93ef96c
--- /dev/null
+++ b/http/upgrade/request/header_check.go
@@ -0,0 +1,130 @@
+package request
+
+import (
+	"git.xdrm.io/gws/internal/http/upgrade/request/parser/header"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+
+
+// checkHost checks and extracts the Host header
+func (r *T) extractHostPort(bb header.HeaderValue) error {
+
+	if len(bb) != 1 {
+		return fmt.Errorf("Host header must have a unique value")
+	}
+
+	split := strings.Split(string(bb[0]), ":")
+
+	r.host = split[0]
+
+	// no port
+	if len(split) < 2 {
+		return nil
+	}
+
+	// extract port
+	readPort, err := strconv.ParseUint(split[1], 10, 16)
+	if err != nil {
+		return fmt.Errorf("Cannot read port number '%s'", split[1])
+	}
+
+	r.port = uint16(readPort)
+
+	// if 'Origin' header is already read, check it
+	if len(r.origin) > 0 {
+		err = r.checkOriginPolicy()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+
+}
+
+
+// checkOrigin checks the Origin Header
+func (r *T) extractOrigin(bb header.HeaderValue) error {
+
+	if len(bb) != 1 {
+		return fmt.Errorf("Origin header must have a unique value")
+	}
+
+	r.origin = string(bb[0])
+
+	// if host already stored, check origin policy
+	if len(r.host) > 0 {
+		err := r.checkOriginPolicy()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+
+}
+
+// checkOriginPolicy origin policy based on 'host' value
+func (r T) checkOriginPolicy() error {
+	// TODO: Origin policy, for now BYPASS
+	return nil
+}
+
+// checkConnection checks the 'Connection' header
+// it MUST contain 'Upgrade'
+func (r T) checkConnection(bb header.HeaderValue) error {
+
+	for _, b := range bb {
+
+		if strings.ToLower( string(b) ) == "upgrade" {
+			return nil
+		}
+
+	}
+
+	return fmt.Errorf("Connection header must be 'Upgrade'")
+
+}
+
+// checkUpgrade checks the 'Upgrade' header
+// it MUST be 'websocket'
+func (r T) checkUpgrade(bb header.HeaderValue) error {
+
+	if len(bb) != 1 {
+		return fmt.Errorf("Upgrade header must have only 1 element")
+	}
+
+	if strings.ToLower( string(bb[0]) ) == "websocket" {
+		return nil
+	}
+
+	return fmt.Errorf("Upgrade header must be 'websocket', got '%s'", bb[0])
+
+}
+
+// checkVersion checks the 'Sec-WebSocket-Version' header
+// it MUST be '13'
+func (r T) checkVersion(bb header.HeaderValue) error {
+
+	if len(bb) != 1 || string(bb[0]) != "13" {
+		return fmt.Errorf("Sec-WebSocket-Version header must be '13'")
+	}
+
+	return nil
+
+}
+
+// extractKey extracts the 'Sec-WebSocket-Key' header
+// it MUST be 24 bytes (base64)
+func (r *T) extractKey(bb header.HeaderValue) error {
+
+	if len(bb) != 1 || len(bb[0]) != 24 {
+		return fmt.Errorf("Sec-WebSocket-Key header must be a unique 24 bytes base64 value, got %d bytes", len(bb[0]))
+	}
+
+	return nil
+
+}
\ No newline at end of file