Add knobs to filter by protocol

dnscrypt-proxy/config.go

@@ -44,6 +44,8 @@ type Config struct {
 	SourceRequireDNSSEC   bool                       `toml:"require_dnssec"`
 	SourceRequireNoLog    bool                       `toml:"require_nolog"`
 	SourceRequireNoFilter bool                       `toml:"require_nofilter"`
+	SourceDNSCrypt        bool                       `toml:"dnscrypt_servers"`
+	SourceDoH             bool                       `toml:"doh_servers"`
 	SourceIPv4            bool                       `toml:"ipv4_servers"`
 	SourceIPv6            bool                       `toml:"ipv6_servers"`
 	MaxClients            uint32                     `toml:"max_clients"`
@@ -68,6 +70,8 @@ func newConfig() Config {
 		SourceRequireNoFilter: true,
 		SourceIPv4:            true,
 		SourceIPv6:            false,
+		SourceDNSCrypt:        true,
+		SourceDoH:             true,
 		MaxClients:            100,
 		FallbackResolver:      DefaultFallbackResolver,
 		IgnoreSystemDNS:       false,
@@ -265,6 +269,8 @@ func ConfigLoad(proxy *Proxy, svcFlag *string) error {
 		config.SourceRequireNoLog = false
 		config.SourceIPv4 = true
 		config.SourceIPv6 = true
+		config.SourceDNSCrypt = true
+		config.SourceDoH = true
 	}
 
 	if err := config.loadSources(proxy); err != nil {
@@ -396,6 +402,10 @@ func (config *Config) loadSource(proxy *Proxy, requiredProps ServerInformalPrope
 				continue
 			}
 		}
+		if !((config.SourceDNSCrypt && registeredServer.stamp.proto == StampProtoTypeDNSCrypt) ||
+			(config.SourceDoH && registeredServer.stamp.proto == StampProtoTypeDoH)) {
+			continue
+		}
 		dlog.Debugf("Adding [%s] to the set of wanted resolvers", registeredServer.name)
 		proxy.registeredServers = append(proxy.registeredServers, registeredServer)
 	}

dnscrypt-proxy/example-dnscrypt-proxy.toml

@@ -41,6 +41,12 @@ ipv4_servers = true
 # Use servers reachable over IPv6 -- Do not enable if you don't have IPv6 connectivity
 ipv6_servers = false
 
+# Use servers implementing the DNSCrypt protocol
+dnscrypt_servers = true
+
+# Use servers implementing the DNS-over-HTTPS protocol
+doh_servers = true
+
 
 ## Require servers defined by remote sources to satisfy specific properties
 
@@ -54,6 +60,7 @@ require_nolog = true
 require_nofilter = true
 
 
+
 ## Always use TCP to connect to upstream servers
 
 force_tcp = false