Name three more reserved ranges in the MCP endpoint blocklist - #112
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Name three more reserved ranges in the MCP endpoint blocklist#112RenKoya1 wants to merge 1 commit into
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The connect-time blocklist is not the SSRF boundary -- workerd's global_fetch_strictly_public is -- but it is what tells a user typing a URL into the connect form why their host will not work. Three ranges of the same class as the entries already there were missing: 100.64.0.0/10 carrier-grade NAT fe80::/10 IPv6 link-local, where only fc00::/7 was covered :: the unspecified address, where only ::1 was covered Without them those hosts reach the fetch and fail as an opaque network error instead.
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BLOCKED_HOST_PATTERNSinmcp-shared/src/endpoint.tsis explicitly not the SSRF boundary —global_fetch_strictly_publicis, and the file says so. What it is for is the other thing the comment names: giving a user typing a URL into the connect form a legible refusal instead of an opaque network error later. Three ranges of exactly the same class as the entries already listed were missing from it:100.64.0.0/10fe80::/10fc00::/7(f[cd]xx:) was covered::::1was coveredNothing else changes: the patterns keep the existing bracket-tolerant style, and
normalizeHostalready feeds them the canonical spelling.Verification
Added the new hosts to the existing blocked-hosts case, plus
100.63.0.1,100.128.0.1and[2606:4700::1111]to the accepted-hosts case so the new patterns are pinned on both sides of their boundaries. That test fails onmain(100.64.0.1: expected true to be false) and passes here.pnpm exec tsc --noEmitclean, fullmcp-sharedsuite 230/230, oxlint reports nothing new.