Class: Stree::Signature

Inherits:
Object
  • Object
show all
Defined in:
lib/stree/signature.rb

Overview

Class responsible for generating signatures to requests.

Implements algorithm defined by Amazon Web Services to sign request with secret private credentials

See:

docs.amazonwebservices.com/AmazonS3/latest/index.html?RESTAuthentication.html

Class Method Summary collapse

Class Method Details

.generate(options) ⇒ Object

Generates signature for given parameters

Parameters:

options: a hash that contains options listed below

Options:

host: hostname request: Net::HTTPRequest object with correct headers access_key_id: access key id secret_access_key: secret access key

Returns:

Generated signature for given hostname and request



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# File 'lib/stree/signature.rb', line 26

def self.generate(options)
  request = options[:request]
  host = options[:host]
  access_key_id = options[:access_key_id]
  secret_access_key = options[:secret_access_key]

  http_verb = request.method
  content_md5 = request["content-md5"] || ""
  content_type = request["content-type"] || ""
  date = request["x-amz-date"].nil? ? request["date"] : ""
  canonicalized_resource = canonicalized_resource(host, request)
  canonicalized_amz_headers = canonicalized_amz_headers(request)

  string_to_sign = ""
  string_to_sign << http_verb
  string_to_sign << "\n"
  string_to_sign << content_md5
  string_to_sign << "\n"
  string_to_sign << content_type
  string_to_sign << "\n"
  string_to_sign << date
  string_to_sign << "\n"
  string_to_sign << canonicalized_amz_headers
  string_to_sign << canonicalized_resource

  digest = OpenSSL::Digest::Digest.new('sha1')
  hmac = OpenSSL::HMAC.digest(digest, secret_access_key, string_to_sign)
  base64 = Base64.encode64(hmac)
  signature = base64.chomp

  "AWS #{access_key_id}:#{signature}"
end