fix: reject hostnames exceeding 253 characters#445
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Jo2234 wants to merge 1 commit intopython-validators:masterfrom
Open
fix: reject hostnames exceeding 253 characters#445Jo2234 wants to merge 1 commit intopython-validators:masterfrom
Jo2234 wants to merge 1 commit intopython-validators:masterfrom
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Per RFC 1123, a hostname must not exceed 253 characters. The existing validator only checked individual label length (≤63 chars via regex) but never validated the total hostname length. This allowed hostnames with multiple short labels separated by dots to pass validation even when the total length exceeded 253 characters. The fix adds an early length check after stripping port and IPv6 brackets, before proceeding with label/domain/IP validation. Fixes python-validators#413
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Summary
Add RFC 1123 conformant total hostname length validation. Hostnames exceeding 253 characters are now correctly rejected.
Problem
The existing hostname validator checked individual label length (≤63 chars via regex) but never validated the total hostname length. Per RFC 1123, a hostname must not exceed 253 characters.
Fix
Added an early length check in
hostname()that:This runs before the existing label/domain/IP validation.
Fixes #413