Class: WebPush::VapidKey

Inherits:
Object
  • Object
show all
Defined in:
lib/web_push/vapid_key.rb

Overview

Class for abstracting the generation and encoding of elliptic curve public and private keys for use with the VAPID protocol

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(pkey = nil) ⇒ VapidKey

Returns a new instance of VapidKey.



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# File 'lib/web_push/vapid_key.rb', line 26

def initialize(pkey = nil)
  @curve = pkey
  @curve = OpenSSL::PKey::EC.generate('prime256v1') if @curve.nil?
end

Instance Attribute Details

#:curve ⇒ OpenSSL::PKey::EC (readonly)

the OpenSSL elliptic curve instance

Returns:

  • (OpenSSL::PKey::EC) —

    the current value of :curve



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# File 'lib/web_push/vapid_key.rb', line 7

def :curve
  @:curve
end

#curve ⇒ Object (readonly)

Returns the value of attribute curve.



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# File 'lib/web_push/vapid_key.rb', line 24

def curve
  @curve
end

Class Method Details

.from_keys(public_key, private_key) ⇒ WebPush::VapidKey

Create a VapidKey instance from encoded elliptic curve public and private keys

Returns:



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# File 'lib/web_push/vapid_key.rb', line 11

def self.from_keys(public_key, private_key)
  key = new
  key.set_keys! public_key, private_key
  key
end

.from_pem(pem) ⇒ WebPush::VapidKey

Create a VapidKey instance from pem encoded elliptic curve public and private keys

Returns:



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# File 'lib/web_push/vapid_key.rb', line 20

def self.from_pem(pem)
  new(OpenSSL::PKey.read(pem))
end

Instance Method Details

#curve_name ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 86

def curve_name
  group.curve_name
end

#group ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 90

def group
  curve.group
end

#inspect ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 111

def inspect
  "#<#{self.class}:#{object_id.to_s(16)} #{to_h.map { |k, v| ":#{k}=#{v}" }.join(' ')}>"
end

#private_key ⇒ String

Retrive the encoded elliptic curve private key for VAPID protocol

Returns:

  • (String) —

    base64 urlsafe-encoded binary representation of 32-byte VAPID private key



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# File 'lib/web_push/vapid_key.rb', line 48

def private_key
  encode64(curve.private_key.to_s(2))
end

#private_key=(key) ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 56

def private_key=(key)
  set_keys! nil, key
end

#private_key_to_pem ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 103

def private_key_to_pem
  curve.to_pem
end

#public_key ⇒ String

Retrieve the encoded elliptic curve public key for VAPID protocol

Returns:

  • (String) —

    encoded binary representation of 65-byte VAPID public key



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# File 'lib/web_push/vapid_key.rb', line 34

def public_key
  encode64(curve.public_key.to_bn.to_s(2))
end

#public_key=(key) ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 52

def public_key=(key)
  set_keys! key, nil
end

#public_key_for_push_header ⇒ String

Retrieve the encoded elliptic curve public key suitable for the Web Push request

Returns:

  • (String) —

    the encoded VAPID public key for us in ‘Encryption’ header



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# File 'lib/web_push/vapid_key.rb', line 41

def public_key_for_push_header
  trim_encode64(curve.public_key.to_bn.to_s(2))
end

#public_key_to_pem ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 107

def public_key_to_pem
  curve.public_to_pem
end

#set_keys!(public_key = nil, private_key = nil) ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 60

def set_keys!(public_key = nil, private_key = nil)
  if public_key.nil?
    public_key = curve.public_key
  else
    public_key = OpenSSL::PKey::EC::Point.new(group, to_big_num(public_key))
  end

  if private_key.nil?
    private_key = curve.private_key
  else
    private_key = to_big_num(private_key)
  end

  asn1 = OpenSSL::ASN1::Sequence([
    OpenSSL::ASN1::Integer.new(1),
    # Not properly padded but OpenSSL doesn't mind
    OpenSSL::ASN1::OctetString(private_key.to_s(2)),
    OpenSSL::ASN1::ObjectId('prime256v1', 0, :EXPLICIT),
    OpenSSL::ASN1::BitString(public_key.to_octet_string(:uncompressed), 1, :EXPLICIT),
  ])

  der = asn1.to_der

  @curve = OpenSSL::PKey::EC.new(der)
end

#to_h ⇒ Object Also known as: to_hash 



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# File 'lib/web_push/vapid_key.rb', line 94

def to_h
  { public_key: public_key, private_key: private_key }
end

#to_pem ⇒ Object 



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# File 'lib/web_push/vapid_key.rb', line 99

def to_pem
  private_key_to_pem + public_key_to_pem
end