DKIM_BUILDER

DNSControl contains a DKIM_BUILDER helper function that generates DKIM DNS TXT records according to RFC 6376 (DomainKeys Identified Mail) and its updates.

Examples

Simple example

dnsconfig.js

D("example.com", REG_MY_PROVIDER, DnsProvider(DSP_MY_PROVIDER),
  DKIM_BUILDER({
    selector: "s1",
    pubkey: "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDC5/z4L"
  }),
);

This yield the following record:

s1._domainkey   IN  TXT "v=DKIM1; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDC5/z4L"

Advanced example

dnsconfig.js

D("example.com", REG_MY_PROVIDER, DnsProvider(DSP_MY_PROVIDER),
  DKIM_BUILDER({
    selector: "k2",
    pubkey: "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDC5/z4L",
    label: "subdomain",
    version: "DKIM1",
    hashtypes: ["sha1", "sha256"],
    keytype: "rsa",
    note: "some human-readable notes",
    servicetypes: ["email"],
    flags: ["y", "s"],
    ttl: 150
  }),
);

This yields the following record:

k2._domainkey.subdomain   IN  TXT "v=DKIM1; h=sha1:sha256; k=rsa; n=some=20human-readable=20notes; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDC5/z4L; s=email; t=y:s" ttl=150

Parameters

• selector (string, required): The selector subdividing the namespace for the domain.

• pubkey (string, optional): The base64-encoded public key (RSA or Ed25519). Default: empty (key revocation or non-sending domain).

• label (string, optional): The DNS label for the DKIM record. Default: @.

• version (string, optional): DKIM version. Maps to the v= tag. Default: DKIM1 (currently the only supported value).

• hashtypes (array, optional): Acceptable hash algorithms for signing. Maps to the h= tag.

  • Supported values for RSA key:

    • sha1

    • sha256

  • Supported values for Ed25519 key:

    • sha256

• keytype (string, optional): Key algorithm type. Maps to the k= tag. Default: rsa. Supported values:

  • rsa

  • ed25519

• note (string, optional): Human-readable notes intended for administrators. Pass normal text here; DKIM-Quoted-Printable encoding will be applied automatically. Maps to the n= tag.

• servicetypes (array, optional): Service types using this key. Maps to the s= tag. Supported values:

  • *: explicitly allows all service types

  • email: restricts key to email service only

• flags (array, optional): Flags to modify the interpretation of the selector. Maps to the t= tag. Supported values:

  • y: Testing mode.

  • s: Subdomain restriction.

• ttl (number, optional): DNS TTL value in seconds

Related RFCs

• RFC 6376: DomainKeys Identified Mail (DKIM) Signatures

• RFC 8301: Cryptographic Algorithm and Key Usage Update to DKIM

• RFC 8463: A New Cryptographic Signature Method for DKIM (Ed25519)