diff options
Diffstat (limited to 'vendor/bundle/ruby/3.4.0/gems/em-websocket-0.5.3/lib/em-websocket/handshake76.rb')
| -rw-r--r-- | vendor/bundle/ruby/3.4.0/gems/em-websocket-0.5.3/lib/em-websocket/handshake76.rb | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/bundle/ruby/3.4.0/gems/em-websocket-0.5.3/lib/em-websocket/handshake76.rb b/vendor/bundle/ruby/3.4.0/gems/em-websocket-0.5.3/lib/em-websocket/handshake76.rb new file mode 100644 index 0000000..c18260d --- /dev/null +++ b/vendor/bundle/ruby/3.4.0/gems/em-websocket-0.5.3/lib/em-websocket/handshake76.rb @@ -0,0 +1,72 @@ +require 'digest/md5' + +module EventMachine::WebSocket + module Handshake76 + class << self + def handshake(headers, path, secure) + challenge_response = solve_challenge( + headers['sec-websocket-key1'], + headers['sec-websocket-key2'], + headers['third-key'] + ) + + scheme = (secure ? "wss" : "ws") + location = "#{scheme}://#{headers['host']}#{path}" + + upgrade = "HTTP/1.1 101 WebSocket Protocol Handshake\r\n" + upgrade << "Upgrade: WebSocket\r\n" + upgrade << "Connection: Upgrade\r\n" + upgrade << "Sec-WebSocket-Location: #{location}\r\n" + upgrade << "Sec-WebSocket-Origin: #{headers['origin']}\r\n" + if protocol = headers['sec-websocket-protocol'] + validate_protocol!(protocol) + upgrade << "Sec-WebSocket-Protocol: #{protocol}\r\n" + end + upgrade << "\r\n" + upgrade << challenge_response + + return upgrade + end + + private + + def solve_challenge(first, second, third) + # Refer to 5.2 4-9 of the draft 76 + sum = [numbers_over_spaces(first)].pack("N*") + + [numbers_over_spaces(second)].pack("N*") + + third + Digest::MD5.digest(sum) + end + + def numbers_over_spaces(string) + unless string + raise HandshakeError, "WebSocket key1 or key2 is missing" + end + + numbers = string.scan(/[0-9]/).join.to_i + + spaces = string.scan(/ /).size + # As per 5.2.5, abort the connection if spaces are zero. + raise HandshakeError, "Websocket Key1 or Key2 does not contain spaces - this is a symptom of a cross-protocol attack" if spaces == 0 + + # As per 5.2.6, abort if numbers is not an integral multiple of spaces + if numbers % spaces != 0 + raise HandshakeError, "Invalid Key #{string.inspect}" + end + + quotient = numbers / spaces + + if quotient > 2**32-1 + raise HandshakeError, "Challenge computation out of range for key #{string.inspect}" + end + + return quotient + end + + def validate_protocol!(protocol) + raise HandshakeError, "Invalid WebSocket-Protocol: empty" if protocol.empty? + # TODO: Validate characters + end + end + end +end |
