Rules

Egern supports multiple types of rules that can be used to control the proxy behavior of network traffic and to block certain traffic.

Supported Rules

Type	Name	Description
domain	Exact Domain Match	Matches the domain exactly
domain_keyword	Domain Keyword Match	Matches domains containing the input keyword
domain_suffix	Domain Suffix Match	Matches domains with the input suffix
domain_regex	Domain Regex Match	Matches domains using regular expressions
geoip	IP Country Code Match	Matches IP addresses based on country code
ip_cidr	IPv4 Range Match	Matches specified IPv4 address ranges
ip_cidr6	IPv6 Range Match	Matches specified IPv6 address ranges
url_regex	URL Regex Match	Matches URLs using regular expressions
rule_set	Rule Set	Local or remote files
asn	ASN Rule	Matches ASN codes or organizations
default	Default Rule	Applied when other rules do not match

• match: The value to match.
• policy: The policy name, which determines how the matched traffic should be handled—such as a proxy server, policy group, direct connection, or rejection. If this value is DIRECT, the matched traffic will not use the proxy. If this value is REJECT, the matched traffic will be blocked. Note that the names of proxy servers and policy groups are applied here.

rules:
  - domain:
      match: www.google.com
      policy: Proxy
  - domain_keyword:
      match: google
      policy: Proxy
  - domain_suffix:
      match: google.com
      policy: Proxy
  - domain_regex:
      match: google|gstatic|ytimg|youtube|ggpht
      policy: Proxy
  - geoip:
      match: US
      policy: Proxy
  - ip_cidr:
      match: 192.168.0.0/16
      policy: DIRECT
  - url_regex:
      match: "https://www.google.com/"
      policy: Proxy
  - rule_set:
      match: "./example.yaml"
      policy: Proxy
  - asn:
      match: "1234"
      policy: DIRECT
  - default:
      policy: DIRECT

In this example, we have set various types of rules. For instance, we use the domain rule to proxy traffic to www.google.com, the domain_keyword rule to proxy traffic to all domains containing google, and the geoip rule to proxy traffic from IP addresses in the United States, among others. The default rule is set to direct connection, meaning that when other rules do not match, traffic will connect directly without using the proxy.

Rule Sets

Rule sets can be local or remote files. They allow you to reuse or share rules across multiple configuration files.

Type	Name
domain_set	Domain Set
domain_keyword_set	Domain Keyword Match Set
domain_suffix_set	Domain Suffix Match Set
domain_regex_set	Domain Regex Match Set
geoip_set	IP Country Code Match Set
ip_cidr_set	IPv4 Range Match Set
ip_cidr6_set	IPv6 Range Match Set
url_regex_set	URL Regex Match Set
asn_set	ASN Rule Set

Rule Set Examples

domain_set:
  - www.google.com
  - www.youtube.com
domain_keyword_set:
  - google
  - youtube
domain_suffix_set:
  - google.com
  - youtube.com
domain_regex_set:
  - google|gstatic|ytimg|youtube|ggpht
geoip_set:
  - US
  - UK
ip_cidr_set:
  - 192.168.0.0/16
url_regex_set:
  - "https://www.google.com/"

In this example, we have set values for each type of rule set. For instance, our domain_set includes www.google.com and www.youtube.com, meaning that when we reference this rule set, traffic to these domains will be matched. Similarly, our geoip_set includes US and UK, so when we reference this rule set, traffic from IP addresses in the United States and the United Kingdom will be matched.