diff options
Diffstat (limited to '')
-rw-r--r-- | src/dns/resolver.rs (renamed from src/server/resolver.rs) | 115 |
1 files changed, 90 insertions, 25 deletions
diff --git a/src/server/resolver.rs b/src/dns/resolver.rs index 464620c..18b5bba 100644 --- a/src/server/resolver.rs +++ b/src/dns/resolver.rs @@ -1,11 +1,7 @@ use super::binding::Connection; -use crate::{ - config::Config, - packet::{ - query::QueryType, question::DnsQuestion, result::ResultCode, Packet, - Result, - }, get_time, -}; +use super::packet::{query::QueryType, question::DnsQuestion, result::ResultCode, Packet}; +use crate::Result; +use crate::{config::Config, database::Database, get_time}; use async_recursion::async_recursion; use moka::future::Cache; use std::{net::IpAddr, sync::Arc, time::Duration}; @@ -15,6 +11,7 @@ pub struct Resolver { request_id: u16, connection: Connection, config: Arc<Config>, + database: Arc<Database>, cache: Cache<DnsQuestion, (Packet, u64)>, } @@ -23,18 +20,59 @@ impl Resolver { request_id: u16, connection: Connection, config: Arc<Config>, + database: Arc<Database>, cache: Cache<DnsQuestion, (Packet, u64)>, ) -> Self { Self { request_id, connection, config, + database, cache, } } - async fn lookup_cache(&mut self, qname: &str, qtype: QueryType) -> Option<Packet> { - let question = DnsQuestion::new(qname.to_string(), qtype); + async fn lookup_database(&self, question: &DnsQuestion) -> Option<Packet> { + let records = match self + .database + .get_records(&question.name, question.qtype) + .await + { + Ok(record) => record, + Err(err) => { + error!("{err}"); + return None; + } + }; + + if records.is_empty() { + return None; + } + + let mut packet = Packet::new(); + + packet.header.id = self.request_id; + packet.header.questions = 1; + packet.header.answers = records.len() as u16; + packet.header.recursion_desired = true; + packet + .questions + .push(DnsQuestion::new(question.name.to_string(), question.qtype)); + + for record in records { + packet.answers.push(record); + } + + trace!( + "Found stored value for {:?} {}", + question.qtype, + question.name + ); + + Some(packet) + } + + async fn lookup_cache(&self, question: &DnsQuestion) -> Option<Packet> { let Some((packet, date)) = self.cache.get(&question) else { return None }; @@ -46,16 +84,20 @@ impl Resolver { let ttl = answer.get_ttl(); if diff > ttl { self.cache.invalidate(&question).await; - return None + return None; } } - trace!("Found cached value for {qtype:?} {qname}"); + trace!( + "Found cached value for {:?} {}", + question.qtype, + question.name + ); Some(packet) } - async fn lookup(&mut self, qname: &str, qtype: QueryType, server: (IpAddr, u16)) -> Packet { + async fn lookup_fallback(&self, question: &DnsQuestion, server: (IpAddr, u16)) -> Packet { let mut packet = Packet::new(); packet.header.id = self.request_id; @@ -63,7 +105,7 @@ impl Resolver { packet.header.recursion_desired = true; packet .questions - .push(DnsQuestion::new(qname.to_string(), qtype)); + .push(DnsQuestion::new(question.name.to_string(), question.qtype)); let packet = match self.connection.request_packet(packet, server).await { Ok(packet) => packet, @@ -78,28 +120,47 @@ impl Resolver { packet } + async fn lookup(&self, question: &DnsQuestion, server: (IpAddr, u16)) -> Packet { + if let Some(packet) = self.lookup_cache(question).await { + return packet; + }; + + if let Some(packet) = self.lookup_database(question).await { + return packet; + }; + + trace!( + "Attempting lookup of {:?} {} with ns {}", + question.qtype, + question.name, + server.0 + ); + + self.lookup_fallback(question, server).await + } + #[async_recursion] async fn recursive_lookup(&mut self, qname: &str, qtype: QueryType) -> Packet { let question = DnsQuestion::new(qname.to_string(), qtype); - let mut ns = self.config.get_fallback_ns().clone(); - - if let Some(packet) = self.lookup_cache(qname, qtype).await { return packet } + let mut ns = self.config.dns_fallback.clone(); loop { - trace!("Attempting lookup of {qtype:?} {qname} with ns {ns}"); - let ns_copy = ns; let server = (ns_copy, 53); - let response = self.lookup(qname, qtype, server).await; + let response = self.lookup(&question, server).await; if !response.answers.is_empty() && response.header.rescode == ResultCode::NOERROR { - self.cache.insert(question, (response.clone(), get_time())).await; + self.cache + .insert(question, (response.clone(), get_time())) + .await; return response; } if response.header.rescode == ResultCode::NXDOMAIN { - self.cache.insert(question, (response.clone(), get_time())).await; + self.cache + .insert(question, (response.clone(), get_time())) + .await; return response; } @@ -111,9 +172,11 @@ impl Resolver { let new_ns_name = match response.get_unresolved_ns(qname) { Some(x) => x, None => { - self.cache.insert(question, (response.clone(), get_time())).await; - return response - }, + self.cache + .insert(question, (response.clone(), get_time())) + .await; + return response; + } }; let recursive_response = self.recursive_lookup(new_ns_name, QueryType::A).await; @@ -121,7 +184,9 @@ impl Resolver { if let Some(new_ns) = recursive_response.get_random_a() { ns = new_ns; } else { - self.cache.insert(question, (response.clone(), get_time())).await; + self.cache + .insert(question, (response.clone(), get_time())) + .await; return response; } } |