Relax header validation for SIP.

.changeset/proud-boats-clean.md

@@ -0,0 +1,5 @@
+---
+"github.com/livekit/protocol": patch
+---
+
+Relax SIP header validation.

livekit/sip.go

@@ -103,9 +103,24 @@ func (p *SIPOutboundTrunkInfo) AsTrunkInfo() *SIPTrunkInfo {
 }
 
 func validateHeader(header string) error {
-	v := strings.ToLower(header)
-	if !strings.HasPrefix(v, "x-") {
-		return fmt.Errorf("only X-* headers are allowed: %s", header)
+	if header == "" {
+		return errors.New("header name is empty")
+	}
+	if strings.ContainsFunc(header, func(r rune) bool {
+		if r >= 'a' && r <= 'z' {
+			return false
+		} else if r >= 'A' && r <= 'Z' {
+			return false
+		} else if r >= '0' && r <= '9' {
+			return false
+		}
+		switch r {
+		case '-':
+			return false
+		}
+		return true
+	}) {
+		return fmt.Errorf("invalid header name: %q", header)
 	}
 	return nil
 }

livekit/sip_test.go

@@ -91,6 +91,16 @@ func TestSIPValidate(t *testing.T) {
 					"From": "from",
 				},
 			},
+			exp: true,
+		},
+		{
+			name: "inbound invalid header",
+			req: &SIPInboundTrunkInfo{
+				Numbers: []string{"+1111"},
+				HeadersToAttributes: map[string]string{
+					"From ": "from",
+				},
+			},
 			exp: false,
 		},
 		{
@@ -165,6 +175,17 @@ func TestSIPValidate(t *testing.T) {
 					"From": "from",
 				},
 			},
+			exp: true,
+		},
+		{
+			name: "outbound invalid header",
+			req: &SIPOutboundTrunkInfo{
+				Address: "sip.example.com",
+				Numbers: []string{"+2222"},
+				HeadersToAttributes: map[string]string{
+					"From ": "from",
+				},
+			},
 			exp: false,
 		},
 	}