Databrick OA 面试真题解析：Firewall Rules 网段访问控制

Firewall Rules

You are given a list of firewall rules. Each rule contains an action, either ALLOW or DENY, and an IPv4 address or CIDR block. Determine how to evaluate the rules and what access should be granted for incoming IP addresses based on the rule list.

Example rules:

• ALLOW 192.168.100.0/24
• DENY 192.168.0.5/30
• ALLOW 192.168.1.1/22
• ALLOW 1.0.0.0/8
• ALLOW 2.3.4.9
• DENY 8.8.8.8/1
• ALLOW 5.6.7.8

这道题考察的是 IP 网段匹配与防火墙规则判断。题目给出一组 ALLOW / DENY 规则，规则可能是单个 IPv4 地址，也可能是 CIDR 网段，需要根据地址是否落在规则覆盖范围内来判断最终访问结果。常见做法是先把 IPv4 转成 32 位整数，再利用掩码判断网段归属；如果规则有优先级或顺序要求，还需要按题意逐条模拟匹配过程。