mirror of
				https://github.com/coredns/coredns.git
				synced 2025-11-03 10:43:20 -05:00 
			
		
		
		
	
		
			
				
	
	
		
			120 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
			
		
		
	
	
			120 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Groff
		
	
	
	
	
	
.\" Generated by Mmark Markdown Processer - mmark.miek.nl
 | 
						||
.TH "COREDNS-ACL" 7 "October 2020" "CoreDNS" "CoreDNS Plugins"
 | 
						||
 | 
						||
.SH "NAME"
 | 
						||
.PP
 | 
						||
\fIacl\fP - enforces access control policies on source ip and prevents unauthorized access to DNS servers.
 | 
						||
 | 
						||
.SH "DESCRIPTION"
 | 
						||
.PP
 | 
						||
With \fB\fCacl\fR enabled, users are able to block suspicious DNS queries by configuring IP filter rule sets, i.e. allowing authorized queries to recurse or blocking unauthorized queries.
 | 
						||
 | 
						||
.PP
 | 
						||
This plugin can be used multiple times per Server Block.
 | 
						||
 | 
						||
.SH "SYNTAX"
 | 
						||
.PP
 | 
						||
.RS
 | 
						||
 | 
						||
.nf
 | 
						||
acl [ZONES...] {
 | 
						||
    ACTION [type QTYPE...] [net SOURCE...]
 | 
						||
}
 | 
						||
 | 
						||
.fi
 | 
						||
.RE
 | 
						||
 | 
						||
.IP \(bu 4
 | 
						||
\fBZONES\fP zones it should be authoritative for. If empty, the zones from the configuration block are used.
 | 
						||
.IP \(bu 4
 | 
						||
\fBACTION\fP (\fIallow\fP or \fIblock\fP) defines the way to deal with DNS queries matched by this rule. The default action is \fIallow\fP, which means a DNS query not matched by any rules will be allowed to recurse.
 | 
						||
.IP \(bu 4
 | 
						||
\fBQTYPE\fP is the query type to match for the requests to be allowed or blocked. Common resource record types are supported. \fB\fC*\fR stands for all record types. The default behavior for an omitted \fB\fCtype QTYPE...\fR is to match all kinds of DNS queries (same as \fB\fCtype *\fR).
 | 
						||
.IP \(bu 4
 | 
						||
\fBSOURCE\fP is the source IP address to match for the requests to be allowed or blocked. Typical CIDR notation and single IP address are supported. \fB\fC*\fR stands for all possible source IP addresses.
 | 
						||
 | 
						||
 | 
						||
.SH "EXAMPLES"
 | 
						||
.PP
 | 
						||
To demonstrate the usage of plugin acl, here we provide some typical examples.
 | 
						||
 | 
						||
.PP
 | 
						||
Block all DNS queries with record type A from 192.168.0.0/16:
 | 
						||
 | 
						||
.PP
 | 
						||
.RS
 | 
						||
 | 
						||
.nf
 | 
						||
\&. {
 | 
						||
    acl {
 | 
						||
        block type A net 192.168.0.0/16
 | 
						||
    }
 | 
						||
}
 | 
						||
 | 
						||
.fi
 | 
						||
.RE
 | 
						||
 | 
						||
.PP
 | 
						||
Block all DNS queries from 192.168.0.0/16 except for 192.168.1.0/24:
 | 
						||
 | 
						||
.PP
 | 
						||
.RS
 | 
						||
 | 
						||
.nf
 | 
						||
\&. {
 | 
						||
    acl {
 | 
						||
        allow net 192.168.1.0/24
 | 
						||
        block net 192.168.0.0/16
 | 
						||
    }
 | 
						||
}
 | 
						||
 | 
						||
.fi
 | 
						||
.RE
 | 
						||
 | 
						||
.PP
 | 
						||
Allow only DNS queries from 192.168.0.0/24 and 192.168.1.0/24:
 | 
						||
 | 
						||
.PP
 | 
						||
.RS
 | 
						||
 | 
						||
.nf
 | 
						||
\&. {
 | 
						||
    acl {
 | 
						||
        allow net 192.168.0.0/24 192.168.1.0/24
 | 
						||
        block
 | 
						||
    }
 | 
						||
}
 | 
						||
 | 
						||
.fi
 | 
						||
.RE
 | 
						||
 | 
						||
.PP
 | 
						||
Block all DNS queries from 192.168.1.0/24 towards a.example.org:
 | 
						||
 | 
						||
.PP
 | 
						||
.RS
 | 
						||
 | 
						||
.nf
 | 
						||
example.org {
 | 
						||
    acl a.example.org {
 | 
						||
        block net 192.168.1.0/24
 | 
						||
    }
 | 
						||
}
 | 
						||
 | 
						||
.fi
 | 
						||
.RE
 | 
						||
 | 
						||
.SH "METRICS"
 | 
						||
.PP
 | 
						||
If monitoring is enabled (via the \fIprometheus\fP plugin) then the following metrics are exported:
 | 
						||
 | 
						||
.IP \(bu 4
 | 
						||
\fB\fCcoredns_acl_blocked_requests_total{server, zone}\fR - counter of DNS requests being blocked.
 | 
						||
.IP \(bu 4
 | 
						||
\fB\fCcoredns_acl_allowed_requests_total{server}\fR - counter of DNS requests being allowed.
 | 
						||
 | 
						||
 | 
						||
.PP
 | 
						||
The \fB\fCserver\fR and \fB\fCzone\fR labels are explained in the \fImetrics\fP plugin documentation.
 | 
						||
 |