fix(dpop): preserve non-default port in pinned Host header and htu#8
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DPoP htu validation failed against Authorization Servers listening on a non-default port. Two coordinated fixes: - The SSRF-safe pinned HTTP client dropped the port from the outbound Host header, so an AS reconstructing the request URI (RFC 9110 §7.2) saw a different authority than the proof's htu (RFC 9449 §4.3). It now emits the port when it is not the scheme default, with IPv6 literals bracketed (RFC 3986 §3.2.2). - DPoP proof generation normalizes the htu claim to match that Host-header rule: an explicit default port (:80/:443) is dropped, non-default ports are kept, and any userinfo is stripped so credentials never leak into the signed proof. Adds regression coverage for the Host header (IPv4 + IPv6), htu default-port normalization, and htu userinfo stripping.
RobertoIskandarani
approved these changes
May 22, 2026
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Summary
DPoP
htuvalidation failed against Authorization Servers listening on anon-default port. This fixes two coordinated issues:
Hostheader, so an AS reconstructing the request URI (RFC 9110 §7.2) saw a
different authority than the proof's
htu(RFC 9449 §4.3). It now emits theport when it is not the scheme default; IPv6 literals stay bracketed
(RFC 3986 §3.2.2).
htuto match that rule: explicit defaultport (
:80/:443) dropped, non-default ports kept, userinfo stripped socredentials never leak into the signed proof.
Tests
hostHeaderunit table (IPv4/IPv6, default/non-default ports)htudefault-port normalization and userinfo-stripping tests