require 'omniauth'
require 'openssl'
require 'base64'
module OmniAuth
module Strategies
class Telegram
include OmniAuth::Strategy
args [:bot_name, :bot_secret]
option :name, 'telegram'
option :bot_name, nil
option :bot_secret, nil
option :button_config, {}
REQUIRED_FIELDS = %w[id hash]
HASH_FIELDS = %w[auth_date first_name id last_name photo_url username]
def request_phase
html = <<-HTML
Telegram Login
HTML
data_attrs = options.button_config.map { |k,v| "data-#{k}=\"#{v}\"" }.join(" ")
html << ""
html << <<-HTML
HTML
Rack::Response.new(html, 200, 'content-type' => 'text/html').finish
end
def callback_phase
if error = check_errors
fail!(error)
else
super
end
end
uid do
request.params["id"]
end
info do
{
name: "#{request.params["first_name"]} #{request.params["last_name"]}",
nickname: request.params["username"],
first_name: request.params["first_name"],
last_name: request.params["last_name"],
image: request.params["photo_url"]
}
end
extra do
{
auth_date: Time.at(request.params["auth_date"].to_i)
}
end
private
def check_errors
return :field_missing unless check_required_fields
return :signature_mismatch unless check_signature
return :session_expired unless check_session
end
def check_required_fields
REQUIRED_FIELDS.all? { |f| request.params.include?(f) }
end
def check_signature
request.params["hash"] == self.class.calculate_signature(options[:bot_secret], request.params)
end
def check_session
Time.now.to_i - request.params["auth_date"].to_i <= 86400
end
def self.calculate_signature(secret, params)
secret = OpenSSL::Digest::SHA256.digest(secret)
signature = generate_comparison_string(params)
OpenSSL::HMAC.hexdigest(OpenSSL::Digest::SHA256.new, secret, signature)
end
def self.generate_comparison_string(params)
(params.keys & HASH_FIELDS).sort.map { |field| "%s=%s" % [field, params[field]] }.join("\n")
end
end
end
end