fix(ctx): drop unsafe URLs in Redirect#46
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Ctx.Redirect previously forwarded any string to the client, so an attacker-controlled value (typical ?next= flows) could yield javascript:, data:, vbscript:, or protocol-relative // open-redirect / XSS frames. Only http, https, and same-origin relative paths are now honoured; everything else is dropped and logged. Leading whitespace and control bytes are trimmed first to match browser scheme parsing.
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Summary
Ctx.Redirectnow validates the URL before queueing a navigation frame: onlyhttp,https, and same-origin relative paths are honoured.javascript:,data:,vbscript:, protocol-relative//…,\\…, and whitespace/case variants are dropped and logged viaapp.logErr.<= ' 'are trimmed before the scheme check to match how browsers parse schemes (javascript:…collapses tojavascript:…).Test plan
go test ./.../tmp/via-verifyapp + curl + Brave): dangerous URLs produced nowindow.location.hrefframe and no browser navigation/alert; safe URLs emitted the expected redirect frame; server log showsRedirect: rejected unsafe URL "…"for every dropped case.