Class: MailAuth::Dkim::Signer

Inherits:
Object
  • Object
show all
Defined in:
lib/mailauth/dkim/signer.rb

Overview

Signs a message per RFC 6376 §5, relaxed/relaxed.

Constant Summary collapse

DEFAULT_SIGNED_HEADERS =

The RFC 6376 §5.4.1 example set: what a reader's client renders or threads on.

%w[
  from sender reply-to subject date message-id to cc
  mime-version content-type content-transfer-encoding
  in-reply-to references list-id list-help list-owner
  list-unsubscribe list-unsubscribe-post list-subscribe list-post
].freeze
OVERSIGNED_HEADERS =

Named in h= once more than they occur — a name past its count matches nothing (§5.4.2), so an instance added after signing breaks the signature.

%w[ from to cc subject date reply-to message-id ].freeze

Instance Method Summary collapse

Constructor Details

#initialize(raw, domain:, selector:, key:, headers: nil, oversign: OVERSIGNED_HEADERS, expires_in: nil, now: Time.now) ⇒ Signer

Returns a new instance of Signer.



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# File 'lib/mailauth/dkim/signer.rb', line 22

def initialize(raw, domain:, selector:, key:, headers: nil, oversign: OVERSIGNED_HEADERS, expires_in: nil, now: Time.now)
  @message = Message.new(raw)
  @domain = Domain.normalize(domain)
  @selector = Domain.normalize(selector)
  @key = key
  @requested = (headers || DEFAULT_SIGNED_HEADERS).map(&:downcase)
  @oversign = oversign.map(&:downcase)
  @expires_in = expires_in
  @now = now
end

Instance Method Details

#field ⇒ Object 



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# File 'lib/mailauth/dkim/signer.rb', line 37

def field
  @field ||= begin
    validate
    unsigned_field + [ signature ].pack("m0").scan(/.{1,72}/).join("\r\n\t") + CRLF
  end
end

#signed_message ⇒ Object 



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# File 'lib/mailauth/dkim/signer.rb', line 33

def signed_message
  field + @message.raw
end