Unify header-size limits into one MAX_HEADER_LIST_SIZE - #44
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Received-message header limits were scattered across eight arbitrary constants with inconsistent values: per-name (1000 vs 1024), per-value (10000 vs 4096), and per-field-count caps in the two HTTP/1 parsers, plus an 8 KB merged-value cap in each builder. The old request scheme was also effectively unbounded in aggregate (10 KB x 1000 fields ~= 10 MB). Replace them all with one shared limit, HttpLimits.MAX_HEADER_LIST_SIZE (32 KiB) — the value HTTP/2 already advertises as SETTINGS_MAX_HEADER_LIST_SIZE. Both HTTP/1 parsers now enforce a single running budget over the header section (sum of field name+value sizes, checked at the append sites); HTTP/2 already enforces the same total during HPACK decode, now sharing the constant. So the limit means the same thing everywhere. Applied to received messages only: requests and origin responses are bounded; responses we generate are not. The builders' merged-value caps are gone (the O(n) StringBuilder accumulator stays — a received merged value is bounded by the parser's total, a generated one is intentionally unbounded). Net: 8 constants -> 1. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Received-message header limits were scattered across eight arbitrary
constants with inconsistent values: per-name (1000 vs 1024), per-value
(10000 vs 4096), and per-field-count caps in the two HTTP/1 parsers, plus an
8 KB merged-value cap in each builder. The old request scheme was also
effectively unbounded in aggregate (10 KB x 1000 fields ~= 10 MB).
Replace them all with one shared limit, HttpLimits.MAX_HEADER_LIST_SIZE (32
KiB) — the value HTTP/2 already advertises as SETTINGS_MAX_HEADER_LIST_SIZE.
Both HTTP/1 parsers now enforce a single running budget over the header
section (sum of field name+value sizes, checked at the append sites); HTTP/2
already enforces the same total during HPACK decode, now sharing the
constant. So the limit means the same thing everywhere.
Applied to received messages only: requests and origin responses are
bounded; responses we generate are not. The builders' merged-value caps are
gone (the O(n) StringBuilder accumulator stays — a received merged value is
bounded by the parser's total, a generated one is intentionally unbounded).
Net: 8 constants -> 1.
Co-Authored-By: Claude Opus 4.8 noreply@anthropic.com