In development mode (-dev):
- HSTS header is omitted (prevents browser caching HTTPS-only requirement)
- CSRF cookie Secure flag is cleared (allows cookies over plain HTTP)
- A warning is logged on startup
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Replace SHA512-based deterministic token with 32-byte crypto/rand token
- Store tokens server-side with 1-hour expiry and single-use semantics
- Remove genToken (previously broken due to time.Add immutability bug)
- Add CSRF double-submit cookie protection to change/lost/reset forms
- Remove token from form action URL (use hidden fields only, POST body)
- Add MailFrom field and SMTP_FROM env var for configurable sender address
- Add SMTP_PASSWORD_FILE env var for secure SMTP password loading
- Add PUBLIC_URL env var and --public-url flag for configurable reset link domain
- Use generic error messages in handlers to avoid information disclosure
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
