dns

Namespace: global/dns

Functions used to query the DNS.

fn resolver

fn resolver(params: ?) -> Result<DnsResolver>

Description

Build a DNS resolver.

Args

TODO

Example

TODO

fn lookup

fn lookup(dns: DnsResolver, host: String) -> Array>

Description

Performs a dual-stack DNS lookup for the given hostname.

Args

• host - A valid hostname to search.

Return

• array - an array of IPs. The array is empty if no IPs were found for the host.

Effective smtp stage

All of them.

Errors

• Root resolver was not found.
• Lookup failed.

Examples

#{
  preq: [
    action "lookup recipients" || {
      let domain = "gmail.com";
      let ips = dns::lookup(domain);

      print(`ips found for ${domain}`);
      for ip in ips { print(`- ${ip}`); }
    },
  ],
}

fn rlookup

fn rlookup(dns: DnsResolver, ip: String) -> Array>

Description

Performs a reverse lookup for the given IP.

Args

• ip - The IP to query.

Return

• array - an array of FQDNs. The array is empty if nothing was found.

Effective smtp stage

All of them.

Errors

• Failed to convert the ip parameter from a string into an IP.
• Reverse lookup failed.

Examples

#{
  connect: [
    rule "rlookup" || {
      state::accept(`250 client ip: ${"127.0.0.1"} - ${dns::rlookup("127.0.0.1")}`);
    }
  ],
}