Set a cache-control header on valid responses

diff --git a/src/http.rs b/src/http.rs
index 5312bbba06b43aac42588653f4827aa43fba2927..98aec6181e1aa32e06eb2bf3fb68cfede3af429d 100644 (file)
--- a/src/http.rs
+++ b/src/http.rs
@@ -116,13 +116,16 @@ mod imp {
                                                "AAAA" => build_aaaa_proof_async(resolver_sockaddr, &query_name).await,
                                                _ => break 'ret_err,
                                        };
-                                       let proof = if let Ok(proof) = proof_res { proof } else {
+                                       let (proof, cache_ttl) = if let Ok(proof) = proof_res { proof } else {
                                                response = ("404 Not Found", "Failed to generate proof for given domain");
                                                break 'ret_err;
                                        };
 
                                        let _ = socket.write_all(
-                                               format!("HTTP/1.1 200 OK\r\nContent-Length: {}\r\nContent-Type: application/octet-stream\r\nAccess-Control-Allow-Origin: *\r\n\r\n", proof.len()).as_bytes()
+                                               format!(
+                                                       "HTTP/1.1 200 OK\r\nContent-Length: {}\r\nContent-Type: application/octet-stream\r\nCache-Control: public, max-age={}, s-maxage={}\r\nAccess-Control-Allow-Origin: *\r\n\r\n",
+                                                       proof.len(), cache_ttl, cache_ttl
+                                               ).as_bytes()
                                        ).await;
                                        let _ = socket.write_all(&proof).await;
                                        return;

diff --git a/src/query.rs b/src/query.rs
index adf687a176c87f7fd733a6ffff637ce5ec813d1e..b73b5b1d4d643f775a2d3ee0a5926405efd4c4fe 100644 (file)
--- a/src/query.rs
+++ b/src/query.rs
@@ -1,6 +1,7 @@
 //! This module exposes utilities for building DNSSEC proofs by directly querying a recursive
 //! resolver.
 
+use std::cmp;
 use std::net::{SocketAddr, TcpStream};
 use std::io::{Read, Write, Error, ErrorKind};
 
@@ -52,7 +53,7 @@ async fn send_query_async(stream: &mut TokioTcpStream, domain: &Name, ty: u16) -
        Ok(())
 }
 
-fn handle_response(resp: &[u8], proof: &mut Vec<u8>) -> Result<Option<RRSig>, Error> {
+fn handle_response(resp: &[u8], proof: &mut Vec<u8>) -> Result<Option<(RRSig, u32)>, Error> {
        let mut read: &[u8] = resp;
        if emap(read_u16(&mut read))? != TXID { return Err(Error::new(ErrorKind::Other, "bad txid")); }
        // 2 byte transaction ID
@@ -81,15 +82,17 @@ fn handle_response(resp: &[u8], proof: &mut Vec<u8>) -> Result<Option<RRSig>, Er
 
        // Only read the answers (skip authorities and additional) as that's all we care about.
        let mut rrsig_opt = None;
+       let mut min_ttl = u32::MAX;
        for _ in 0..answers {
                let (rr, ttl) = emap(parse_wire_packet_rr(&mut read, &resp))?;
                write_rr(&rr, ttl, proof);
+               min_ttl = cmp::min(min_ttl, ttl);
                if let RR::RRSig(rrsig) = rr { rrsig_opt = Some(rrsig); }
        }
-       Ok(rrsig_opt)
+       Ok(rrsig_opt.map(|rr| (rr, min_ttl)))
 }
 
-fn read_response(stream: &mut TcpStream, proof: &mut Vec<u8>) -> Result<Option<RRSig>, Error> {
+fn read_response(stream: &mut TcpStream, proof: &mut Vec<u8>) -> Result<Option<(RRSig, u32)>, Error> {
        let mut len = [0; 2];
        stream.read_exact(&mut len)?;
        let mut resp = vec![0; u16::from_be_bytes(len) as usize];
@@ -98,7 +101,7 @@ fn read_response(stream: &mut TcpStream, proof: &mut Vec<u8>) -> Result<Option<R
 }
 
 #[cfg(feature = "tokio")]
-async fn read_response_async(stream: &mut TokioTcpStream, proof: &mut Vec<u8>) -> Result<Option<RRSig>, Error> {
+async fn read_response_async(stream: &mut TokioTcpStream, proof: &mut Vec<u8>) -> Result<Option<(RRSig, u32)>, Error> {
        let mut len = [0; 2];
        stream.read_exact(&mut len).await?;
        let mut resp = vec![0; u16::from_be_bytes(len) as usize];
@@ -110,10 +113,12 @@ macro_rules! build_proof_impl {
        ($stream: ident, $send_query: ident, $read_response: ident $(, $async_ok: tt)?) => { {
                let mut res = Vec::new();
                let mut reached_root = false;
+               let mut min_ttl = u32::MAX;
                for i in 0..10 {
-                       let rrsig_opt = $read_response(&mut $stream, &mut res)
+                       let resp_opt = $read_response(&mut $stream, &mut res)
                                $(.await?; $async_ok)??; // Either await?; Ok(())?, or just ?
-                       if let Some(rrsig) = rrsig_opt {
+                       if let Some((rrsig, rrsig_min_ttl)) = resp_opt {
+                               min_ttl = cmp::min(min_ttl, rrsig_min_ttl);
                                if rrsig.name.as_str() == "." {
                                        reached_root = true;
                                } else {
@@ -128,65 +133,73 @@ macro_rules! build_proof_impl {
                }
 
                if !reached_root { Err(Error::new(ErrorKind::Other, "Too many requests required")) }
-               else { Ok(res) }
+               else { Ok((res, min_ttl)) }
        } }
 }
 
-fn build_proof(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<Vec<u8>, Error> {
+fn build_proof(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<(Vec<u8>, u32), Error> {
        let mut stream = TcpStream::connect(resolver)?;
        send_query(&mut stream, domain, ty)?;
        build_proof_impl!(stream, send_query, read_response)
 }
 
 #[cfg(feature = "tokio")]
-async fn build_proof_async(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<Vec<u8>, Error> {
+async fn build_proof_async(resolver: SocketAddr, domain: &Name, ty: u16) -> Result<(Vec<u8>, u32), Error> {
        let mut stream = TokioTcpStream::connect(resolver).await?;
        send_query_async(&mut stream, domain, ty).await?;
        build_proof_impl!(stream, send_query_async, read_response_async, { Ok::<(), Error>(()) })
 }
 
-/// Builds a DNSSEC proof for an A record by querying a recursive resolver
-pub fn build_a_proof(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+/// Builds a DNSSEC proof for an A record by querying a recursive resolver, returning the proof as
+/// well as the TTL for the proof provided by the recursive resolver.
+pub fn build_a_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof(resolver, domain, A::TYPE)
 }
 
-/// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver
-pub fn build_aaaa_proof(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+/// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
+pub fn build_aaaa_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof(resolver, domain, AAAA::TYPE)
 }
 
-/// Builds a DNSSEC proof for a TXT record by querying a recursive resolver
-pub fn build_txt_proof(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+/// Builds a DNSSEC proof for an TXT record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
+pub fn build_txt_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof(resolver, domain, Txt::TYPE)
 }
 
-/// Builds a DNSSEC proof for a TLSA record by querying a recursive resolver
-pub fn build_tlsa_proof(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+/// Builds a DNSSEC proof for an TLSA record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
+pub fn build_tlsa_proof(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof(resolver, domain, TLSA::TYPE)
 }
 
 
-/// Builds a DNSSEC proof for an A record by querying a recursive resolver
+/// Builds a DNSSEC proof for an A record by querying a recursive resolver, returning the proof as
+/// well as the TTL for the proof provided by the recursive resolver.
 #[cfg(feature = "tokio")]
-pub async fn build_a_proof_async(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+pub async fn build_a_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof_async(resolver, domain, A::TYPE).await
 }
 
-/// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver
+/// Builds a DNSSEC proof for an AAAA record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
 #[cfg(feature = "tokio")]
-pub async fn build_aaaa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+pub async fn build_aaaa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof_async(resolver, domain, AAAA::TYPE).await
 }
 
-/// Builds a DNSSEC proof for a TXT record by querying a recursive resolver
+/// Builds a DNSSEC proof for an TXT record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
 #[cfg(feature = "tokio")]
-pub async fn build_txt_proof_async(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+pub async fn build_txt_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof_async(resolver, domain, Txt::TYPE).await
 }
 
-/// Builds a DNSSEC proof for a TLSA record by querying a recursive resolver
+/// Builds a DNSSEC proof for an TLSA record by querying a recursive resolver, returning the proof
+/// as well as the TTL for the proof provided by the recursive resolver.
 #[cfg(feature = "tokio")]
-pub async fn build_tlsa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<Vec<u8>, Error> {
+pub async fn build_tlsa_proof_async(resolver: SocketAddr, domain: &Name) -> Result<(Vec<u8>, u32), Error> {
        build_proof_async(resolver, domain, TLSA::TYPE).await
 }
 
@@ -205,7 +218,7 @@ mod tests {
        fn test_cloudflare_txt_query() {
                let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
                let query_name = "cloudflare.com.".try_into().unwrap();
-               let proof = build_txt_proof(sockaddr, &query_name).unwrap();
+               let (proof, _) = build_txt_proof(sockaddr, &query_name).unwrap();
 
                let mut rrs = parse_rr_stream(&proof).unwrap();
                rrs.shuffle(&mut rand::rngs::OsRng);
@@ -221,7 +234,7 @@ mod tests {
        fn test_sha1_query() {
                let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
                let query_name = "benthecarman.com.".try_into().unwrap();
-               let proof = build_a_proof(sockaddr, &query_name).unwrap();
+               let (proof, _) = build_a_proof(sockaddr, &query_name).unwrap();
 
                let mut rrs = parse_rr_stream(&proof).unwrap();
                rrs.shuffle(&mut rand::rngs::OsRng);
@@ -237,7 +250,7 @@ mod tests {
        fn test_txt_query() {
                let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
                let query_name = "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap();
-               let proof = build_txt_proof(sockaddr, &query_name).unwrap();
+               let (proof, _) = build_txt_proof(sockaddr, &query_name).unwrap();
 
                let mut rrs = parse_rr_stream(&proof).unwrap();
                rrs.shuffle(&mut rand::rngs::OsRng);
@@ -257,7 +270,7 @@ mod tests {
        async fn test_txt_query_async() {
                let sockaddr = "8.8.8.8:53".to_socket_addrs().unwrap().next().unwrap();
                let query_name = "matt.user._bitcoin-payment.mattcorallo.com.".try_into().unwrap();
-               let proof = build_txt_proof_async(sockaddr, &query_name).await.unwrap();
+               let (proof, _) = build_txt_proof_async(sockaddr, &query_name).await.unwrap();
 
                let mut rrs = parse_rr_stream(&proof).unwrap();
                rrs.shuffle(&mut rand::rngs::OsRng);