Reject IDNA dot-variant hosts that normalize to IP literals - #920
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normalize/2 gated hosts that percent-decode to an IP literal but ran the check before idnconvert_hostname. IDNA folds the Unicode full-stop variants U+3002/U+FF0E/U+FF61 onto ASCII dots, so a host like 127<U+3002>0<U+3002>0<U+3002>1 is not an IP literal at the gate yet normalizes to 127.0.0.1, slipping past a caller-side SSRF allowlist. Canonicalize those full-stop variants before the IP gate so both the raw and percent-encoded forms are rejected the same way, independent of the idna library's leniency.
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hackney_url:normalize/2rejects hosts that percent-decode to an IP literal, but the check runs beforeidnconvert_hostname/1. IDNA folds the Unicode full-stop variants (U+3002, U+FF0E, U+FF61) onto ASCII dots, so a host like127<U+3002>0<U+3002>0<U+3002>1is not an IP literal at the gate yet normalizes to127.0.0.1, bypassing a caller-side SSRF allowlist that ran on the pre-normalized host. Canonicalize those variants before the IP gate so the raw and percent-encoded forms are rejected the same way, independent of the idna library's leniency.