Configurable multiple dns resolvers

src/config/dns.rs

@@ -0,0 +1,99 @@
+use serde::{Deserialize,Serialize};
+use trust_dns_resolver::config::Protocol;
+use trust_dns_resolver::Name;
+
+use std::collections::HashMap;
+use std::net::SocketAddr;
+
+#[derive(Deserialize, Clone)]
+pub struct DnsConfig {
+	pub allow_forward_lookup: bool,
+	pub allow_reverse_lookup: bool,
+	pub hidden_suffixes: Vec<String>,
+	#[serde(default="default_dns_resolver_name")]
+	pub default_resolver: String,
+	pub resolver: HashMap<String,DnsResolverConfig>,
+}
+
+#[derive(Deserialize, Serialize, Clone)]
+pub enum DnsProtocol {
+	Udp,
+	Tcp,
+	Tls,
+	Https,
+	Quic,
+}
+
+pub fn default_dns_resolver_name() -> String {
+	"default".to_string()
+}
+
+#[derive(Deserialize, Serialize, Clone)]
+pub struct DnsResolverConfig {
+	pub display_name: String,
+	#[serde(default="zero")]
+	pub weight: i32,
+	pub servers: Vec<SocketAddr>,
+	#[serde(default)]
+	pub search: Vec<String>,
+	pub protocol: DnsProtocol,
+	pub tls_dns_name: Option<String>,
+	pub bind_address: Option<SocketAddr>,
+	#[serde(default="default_true")]
+	pub trust_nx_responses: bool,
+}
+
+fn zero() -> i32 {
+	return 0;
+}
+
+fn default_true() -> bool {
+	return true;
+}
+
+impl Default for DnsConfig {
+	fn default() -> Self {
+		DnsConfig {
+			allow_forward_lookup: true,
+			allow_reverse_lookup: false,
+			hidden_suffixes: Vec::new(),
+			default_resolver: "default".to_string(),
+			resolver: Default::default(),
+		}
+	}
+}
+
+impl Into<Protocol> for DnsProtocol {
+	fn into(self) -> Protocol {
+		match self {
+			Self::Udp   => Protocol::Udp,
+			Self::Tcp   => Protocol::Tcp,
+			Self::Tls   => Protocol::Tls,
+			Self::Https => Protocol::Https,
+			Self::Quic  => Protocol::Quic,
+		}
+	}
+}
+
+impl DnsResolverConfig {
+	pub fn to_trust_resolver_config(&self) -> trust_dns_resolver::config::ResolverConfig {
+		let mut resolver = trust_dns_resolver::config::ResolverConfig::new();
+		for server in &self.servers {
+			resolver.add_name_server(trust_dns_resolver::config::NameServerConfig{
+				socket_addr: *server,
+				protocol: self.protocol.clone().into(),
+				tls_dns_name: self.tls_dns_name.clone(),
+				trust_nx_responses: self.trust_nx_responses,
+				tls_config: None,
+				bind_addr: self.bind_address,
+			});
+		}
+		for search in &self.search {
+			if let Ok(name) = Name::from_str_relaxed(search) {
+				resolver.add_search(name);
+			}
+		}
+		return resolver;
+	}
+}
+