badguardhome/dnsforward/util.go

77 lines
1.5 KiB
Go

package dnsforward
import (
"net"
"sort"
"strings"
"github.com/AdguardTeam/golibs/utils"
)
func stringArrayDup(a []string) []string {
a2 := make([]string, len(a))
copy(a2, a)
return a2
}
// Get IP address from net.Addr object
// Note: we can't use net.SplitHostPort(a.String()) because of IPv6 zone:
// https://github.com/AdguardTeam/AdGuardHome/issues/1261
func ipFromAddr(a net.Addr) string {
switch addr := a.(type) {
case *net.UDPAddr:
return addr.IP.String()
case *net.TCPAddr:
return addr.IP.String()
}
return ""
}
// Get IP address from net.Addr
func getIP(addr net.Addr) net.IP {
switch addr := addr.(type) {
case *net.UDPAddr:
return addr.IP
case *net.TCPAddr:
return addr.IP
}
return nil
}
// Find value in a sorted array
func findSorted(ar []string, val string) int {
i := sort.SearchStrings(ar, val)
if i == len(ar) || ar[i] != val {
return -1
}
return i
}
func isWildcard(host string) bool {
return len(host) >= 2 &&
host[0] == '*' && host[1] == '.'
}
// Return TRUE if host name matches a wildcard pattern
func matchDomainWildcard(host, wildcard string) bool {
return isWildcard(wildcard) &&
strings.HasSuffix(host, wildcard[1:])
}
// Return TRUE if client's SNI value matches DNS names from certificate
func matchDNSName(dnsNames []string, sni string) bool {
if utils.IsValidHostname(sni) != nil {
return false
}
if findSorted(dnsNames, sni) != -1 {
return true
}
for _, dn := range dnsNames {
if matchDomainWildcard(sni, dn) {
return true
}
}
return false
}