[PR #3156] [MERGED] Recursor: better handling of cached referral responses #3604

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opened 2026-03-16 11:52:36 +03:00 by kerem · 0 comments

kerem commented

2026-03-16 11:52:36 +03:00

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📋 Pull Request Information

Original PR: https://github.com/hickory-dns/hickory-dns/pull/3156
Author: @divergentdave
Created: 7/24/2025
Status: ✅ Merged
Merged: 7/29/2025
Merged by: @divergentdave

Base: main ← Head: david/recursor-cache-referral-handling

📝 Commits (8)

fe9c140 Split cache fetch out of RecursorDnsHandle::lookup
de0ee9e Flatten match arms
17592f0 Inline and simplify one method call
ba79235 Flip if statement condition
5755c3d Ignore cached referral responses
e4600da Check AA on cache entries in two other places
0aa4a39 Remove "any matching RRSIG" logic on cache fetches
0d66908 Use structured logging

📊 Changes

4 files changed (+60 additions, -62 deletions)

View changed files

📝 conformance/packages/conformance-tests/src/resolver/dns/regression.rs (+0 -1)
📝 conformance/packages/conformance-tests/src/resolver/dnssec/scenarios/no_soa.rs (+1 -0)
📝 crates/recursor/src/recursor.rs (+3 -3)
📝 crates/recursor/src/recursor_dns_handle.rs (+56 -58)

📄 Description

This changes the recursor so that we only re-use cached referral responses in the context of ns_pool_for_zone(), and ignore them everywhere else. Looking at the header flags lets us remove some complicated DNSSEC-specific logic as well.

I'm opening this as a draft for now, stacked on top of #3155. This is related to #3008 and #3125.

_{🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.}

## 📋 Pull Request Information **Original PR:** https://github.com/hickory-dns/hickory-dns/pull/3156 **Author:** [@divergentdave](https://github.com/divergentdave) **Created:** 7/24/2025 **Status:** ✅ Merged **Merged:** 7/29/2025 **Merged by:** [@divergentdave](https://github.com/divergentdave) **Base:** `main` ← **Head:** `david/recursor-cache-referral-handling` --- ### 📝 Commits (8) - [`fe9c140`](https://github.com/hickory-dns/hickory-dns/commit/fe9c1406899ca17c6f50ae5988ee51a6579e4963) Split cache fetch out of RecursorDnsHandle::lookup - [`de0ee9e`](https://github.com/hickory-dns/hickory-dns/commit/de0ee9ec5b1f7fe79b649987310f59dfcf270ec3) Flatten match arms - [`17592f0`](https://github.com/hickory-dns/hickory-dns/commit/17592f0cbbcd5d1e0e00364289f103dad73131f9) Inline and simplify one method call - [`ba79235`](https://github.com/hickory-dns/hickory-dns/commit/ba7923506b64325417d1fc08a64dc1fbb68c1059) Flip if statement condition - [`5755c3d`](https://github.com/hickory-dns/hickory-dns/commit/5755c3dd51102949389ff1900e84a172207f456d) Ignore cached referral responses - [`e4600da`](https://github.com/hickory-dns/hickory-dns/commit/e4600da3cc57ad4e8dac6bd39f06460db08d5ce2) Check AA on cache entries in two other places - [`0aa4a39`](https://github.com/hickory-dns/hickory-dns/commit/0aa4a398874eee656ca15ec4199e6751b925fc4d) Remove "any matching RRSIG" logic on cache fetches - [`0d66908`](https://github.com/hickory-dns/hickory-dns/commit/0d6690835a047f2997ede53cd5eb06cd1da181e4) Use structured logging ### 📊 Changes **4 files changed** (+60 additions, -62 deletions) <details> <summary>View changed files</summary> 📝 `conformance/packages/conformance-tests/src/resolver/dns/regression.rs` (+0 -1) 📝 `conformance/packages/conformance-tests/src/resolver/dnssec/scenarios/no_soa.rs` (+1 -0) 📝 `crates/recursor/src/recursor.rs` (+3 -3) 📝 `crates/recursor/src/recursor_dns_handle.rs` (+56 -58) </details> ### 📄 Description This changes the recursor so that we only re-use cached referral responses in the context of `ns_pool_for_zone()`, and ignore them everywhere else. Looking at the header flags lets us remove some complicated DNSSEC-specific logic as well. I'm opening this as a draft for now, stacked on top of #3155. This is related to #3008 and #3125. --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>