From 64cd83a440f28351fec508526d2afa6605c22388 Mon Sep 17 00:00:00 2001
From: Frank Denis <you@example.com>
Date: Thu, 9 Jul 2020 21:08:34 +0200
Subject: [PATCH] Don't use the TTL for stale-if-error and
 stale-while-revalidate

Use constant, reasonable values instead
---
 src/libdoh/src/constants.rs | 2 ++
 src/libdoh/src/lib.rs       | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/libdoh/src/constants.rs b/src/libdoh/src/constants.rs
index e2e30b2..69df765 100644
--- a/src/libdoh/src/constants.rs
+++ b/src/libdoh/src/constants.rs
@@ -2,3 +2,5 @@ pub const DNS_QUERY_PARAM: &str = "dns";
 pub const MAX_DNS_QUESTION_LEN: usize = 512;
 pub const MAX_DNS_RESPONSE_LEN: usize = 4096;
 pub const MIN_DNS_PACKET_LEN: usize = 17;
+pub const STALE_IF_ERROR_SECS: u32 = 3600;
+pub const STALE_WHILE_REVALIDATE_SECS: u32 = 60;
diff --git a/src/libdoh/src/lib.rs b/src/libdoh/src/lib.rs
index 6b4ca0b..44477d4 100644
--- a/src/libdoh/src/lib.rs
+++ b/src/libdoh/src/lib.rs
@@ -212,7 +212,11 @@ impl DoH {
             .header(hyper::header::CONTENT_TYPE, "application/dns-message")
             .header(
                 hyper::header::CACHE_CONTROL,
-                format!("max-age={}, stale-while-revalidate={}, stale-if-error={}", ttl, ttl, ttl).as_str(),
+                format!(
+                    "max-age={}, stale-if-error={}, stale-while-revalidate={}",
+                    ttl, STALE_IF_ERROR_SECS, STALE_WHILE_REVALIDATE_SECS
+                )
+                .as_str(),
             )
             .body(Body::from(packet))
             .unwrap();