內容簡介
SiteGuarding Math Captcha 是一款有效防止垃圾郵件的外掛，要求訪客在提交表單前解答簡單的數學題。此外掛不依賴第三方服務，所有運算均在您的網站上進行，確保隱私與安全。
【主要功能】
• 支援多種表單：登入、註冊、留言等
• 自訂數學題型：加減乘除，數字範圍1至99
• 自動添加至多個外掛表單中
• IP與國家規則：可封鎖特定IP或國家
• 統計功能：檢查失敗次數與來源
• 隱私保護：不設置Cookies，定期刪除IP地址
外掛標籤
開發者團隊
原文外掛簡介
SiteGuarding Math Captcha asks visitors to solve a small example such as “7 + ? = 12” before a form is sent. People answer it in a second; most spam bots do not. There are no cookies, no tracking and no third-party captcha service: everything runs on your own site.
Where it works
WordPress login, registration (including multisite sign-up), lost password and comment forms
WooCommerce: login, registration, lost password, checkout (classic checkout and the checkout block), product reviews and the order tracking form
Contact Form 7, WPForms (Lite and Pro), Formidable Forms, Ninja Forms, Fluent Forms and Forminator: the captcha is added before the submit button of every form automatically (Fluent Forms conversational forms are not covered)
bbPress new topics and replies
Your own forms: add the [sgmathcp_captcha] shortcode and check the answer with sgmathcp_verify(), or list pages under “Protected pages” and every form posted to them is checked for you
Captcha options
Addition, subtraction, multiplication and division with numbers from 1 to 99
Numbers as digits, as words in the language of your site, or mixed
Your own title above the example and your own time limit
Hidden for logged-in users if you wish (login, registration and lost password forms always ask)
A hidden trap field that only bots fill in
Works with page caching: a fresh example is loaded when a visitor starts filling a cached form
Every example can be used only once, so a solved captcha cannot be replayed
IP and country rules
Never show the captcha to trusted IP addresses or countries
Block IP addresses, ranges (CIDR, wildcards, from-to) and countries, IPv4 and IPv6
Lock an IP address for a while after too many wrong answers (an IPv6 address is locked with its /64 network)
Block rules apply to logged-in users too
Country detection from a free public domain database or from the Cloudflare country header
The visitor address is taken from the connection; proxy headers are trusted only from Cloudflare or from proxies you list, so bots cannot fake their address
Statistics
Failed checks by hour or by day, from today to the last 12 months
Top countries, top IP addresses with a one-click block, and failures by form and reason
Optional counter of today’s failed checks in the admin bar (off by default)
Limited retention of IP addresses and an option to store them shortened
Privacy
The captcha sets no cookies. When a check fails, the plugin stores the IP address, its country, the form and the time in your database to block repeated attempts and to show statistics. IP addresses are deleted automatically after the number of days you choose (90 by default). A suggested text for your privacy policy is added under Settings > Privacy.
External services
This plugin can download a free IP-to-country database so that country rules work. Nothing is downloaded unless an administrator clicks “Download database” or “Update now” on the IP & GEO tab, or enables the monthly update there.
What: the “user-country” database of the ip-location-db project, published in the public domain (PDDL 1.0), about 7 MB.
Where from: https://github.com/sapics/ip-location-db/releases (github.com redirects the download to release-assets.githubusercontent.com). A checksum file is read from the same place to verify the download.
What is sent: a normal file request. Like any web request it shows the IP address of your server to GitHub. No data about your visitors or your site is sent.
GitHub terms of service: https://docs.github.com/site-policy/github-terms/github-terms-of-service
GitHub privacy statement: https://docs.github.com/site-policy/privacy-policies/github-general-privacy-statement
You can upload your own database in MaxMind DB format instead (for example GeoLite2 Country with your own MaxMind license).
