Simplify verification of hostname in ssl certificates

core/pkg/ingress/controller/util.go

@@ -17,9 +17,6 @@ limitations under the License.
 package controller
 
 import (
-	"strings"
-	"unicode/utf8"
-
 	"github.com/golang/glog"
 	"github.com/imdario/mergo"
 
@@ -47,80 +44,6 @@ func newUpstream(name string) *ingress.Backend {
 	}
 }
 
-func isHostValid(host string, cert *ingress.SSLCert) bool {
-	if cert == nil {
-		return false
-	}
-
-	lowered := toLowerCaseASCII(host)
-	for _, cn := range cert.CN {
-		if matchHostnames(toLowerCaseASCII(cn), lowered) {
-			return true
-		}
-	}
-
-	return false
-}
-
-func matchHostnames(pattern, host string) bool {
-	host = strings.TrimSuffix(host, ".")
-	pattern = strings.TrimSuffix(pattern, ".")
-
-	if len(pattern) == 0 || len(host) == 0 {
-		return false
-	}
-
-	patternParts := strings.Split(pattern, ".")
-	hostParts := strings.Split(host, ".")
-
-	if len(patternParts) != len(hostParts) {
-		return false
-	}
-
-	for i, patternPart := range patternParts {
-		if i == 0 && patternPart == "*" {
-			continue
-		}
-		if patternPart != hostParts[i] {
-			return false
-		}
-	}
-
-	return true
-}
-
-// toLowerCaseASCII returns a lower-case version of in. See RFC 6125 6.4.1. We use
-// an explicitly ASCII function to avoid any sharp corners resulting from
-// performing Unicode operations on DNS labels.
-func toLowerCaseASCII(in string) string {
-	// If the string is already lower-case then there's nothing to do.
-	isAlreadyLowerCase := true
-	for _, c := range in {
-		if c == utf8.RuneError {
-			// If we get a UTF-8 error then there might be
-			// upper-case ASCII bytes in the invalid sequence.
-			isAlreadyLowerCase = false
-			break
-		}
-		if 'A' <= c && c <= 'Z' {
-			isAlreadyLowerCase = false
-			break
-		}
-	}
-
-	if isAlreadyLowerCase {
-		return in
-	}
-
-	out := []byte(in)
-	for i, c := range out {
-		if 'A' <= c && c <= 'Z' {
-			out[i] += 'a' - 'A'
-		}
-	}
-	return string(out)
-}
-
 func mergeLocationAnnotations(loc *ingress.Location, anns map[string]interface{}) {
 	if _, ok := anns[DeniedKeyName]; ok {
 		loc.Denied = anns[DeniedKeyName].(error)