Class: EM::Mongo::SCRAM
- Inherits:
-
Authentication
- Object
- Authentication
- EM::Mongo::SCRAM
- Defined in:
- lib/em-mongo/auth/scram.rb
Overview
an RFC 5802 compilant SCRAM(-SHA-1) implementation for MongoDB-Authentication
so everything is encapsulated, but the main part (PAYLOAD of messages) is RFC5802 compilant
Defined Under Namespace
Classes: FirstMessage
Constant Summary collapse
- MECHANISM =
'SCRAM-SHA-1'.freeze
- DIGEST =
OpenSSL::Digest::SHA1.new.freeze
- CLIENT_FIRST_MESSAGE =
{ saslStart: 1, autoAuthorize: 1 }.freeze
- CLIENT_FINAL_MESSAGE =
CLIENT_EMPTY_MESSAGE = { saslContinue: 1 }.freeze
- CLIENT_KEY =
'Client Key'.freeze
- SERVER_KEY =
'Server Key'.freeze
- RNONCE =
/r=([^,]*)/.freeze
- SALT =
/s=([^,]*)/.freeze
- ITERATIONS =
/i=(\d+)/.freeze
- VERIFIER =
/v=([^,]*)/.freeze
- PAYLOAD =
'payload'.freeze
Constants inherited from Authentication
Authentication::SYSTEM_COMMAND_COLLECTION
Instance Method Summary collapse
-
#authenticate(username, password) ⇒ EM::Mongo::RequestResponse
Calls back with
true
orfalse
, indicating success or failure. - #client_key ⇒ Object
- #client_nonce ⇒ Object
-
#client_signature ⇒ Object
needs @username, @plain_password, @salt, @iterations, @auth_message defined.
-
#handle_server_end(response, conv_id) ⇒ Object
MongoDB handles the end of authentication different than in RFC 5802 it needs at least an additional empty response (this needs to be iterated until res=true (at least it is done so in the official mongo-ruby-drive (at least it is done so in the official mongo-ruby-driver)) -> recursion (is technically more loop than recursion but here it’s one).
-
#hashed_password ⇒ Object
needs @username, @plain_password defined.
- #hi(password, salt, iterations) ⇒ Object
- #hmac(data, key) ⇒ Object
-
#is_server_response_valid?(response) ⇒ Boolean
to be valid the response has to * be not nil * contain at least [‘done’], [‘ok’], [‘payload’], [‘conversationId’] * [‘ok’].to_i has to be 1 * [‘conversationId’] has to match the first sent one.
-
#salted_password ⇒ Object
needs @username, @plain_password, @salt, @iterations defined.
-
#server_key ⇒ Object
server_key = hmac(salted_password,“Server Key”).
-
#server_signature ⇒ Object
server_signature = B64(hmac(server_key, auth_message).
-
#verifier_valid?(verifier) ⇒ Boolean
verify the verifier (v=…).
-
#xor(first, second) ⇒ Object
xor for strings.
Methods inherited from Authentication
Constructor Details
This class inherits a constructor from EM::Mongo::Authentication
Instance Method Details
#authenticate(username, password) ⇒ EM::Mongo::RequestResponse
Returns Calls back with true
or false
, indicating success or failure.
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# File 'lib/em-mongo/auth/scram.rb', line 40 def authenticate(username, password) response = RequestResponse.new #TODO look for fail-fast-ness (strange word!?) #TODO Flatten Hierarchies @username = username @plain_password = password gs2_header = 'n,,' = "n=#{@username},r=#{client_nonce}" client_first = BSON::Binary.new(gs2_header+) # client_first msg client_first_msg = CLIENT_FIRST_MESSAGE.merge({PAYLOAD=>client_first, mechanism:MECHANISM}) client_first_resp = @db.collection(EM::Mongo::Database::SYSTEM_COMMAND_COLLECTION).first(client_first_msg) #TODO extract and make easier to understand (e.g. command(first_msg) or sthg like that) #server_first_resp #for flattening client_first_resp.callback do |res_first| if not is_server_response_valid? res_first response.fail "first server response not valid: " + res_first.to_s else # take the salt & iterations and do the pw-derivation server_first = res_first[PAYLOAD].to_s @conversation_id=conv_id = res_first['conversationId'] combined_nonce = server_first.match(RNONCE)[1] #r= ... salt = server_first.match( SALT )[1] #s=... (from server_first) iterations = server_first.match(ITERATIONS)[1].to_i #i=... .. if not combined_nonce.start_with?(client_nonce) # combined_nonce should be client_nonce+server_nonce response.fail "nonce doesn't start with client_nonce: " + res_first.to_s else client_final_wo_proof= "c=#{Base64.strict_encode64(gs2_header)},r=#{combined_nonce}" #c='biws' = + ',' + server_first + ',' + client_final_wo_proof # proof = clientKey XOR clientSig ## needs to be sent back # # ClientSign = HMAC(StoredKey, AuthMessage) # StoredKey = H(ClientKey) ## lt. RFC5802 (needs to be verified against ruby-mongo driver impl) # AuthMessage = client_first_bare + ','+server_first+','+client_final_wo_proof @salt = salt @iterations = iterations #client_key = client_key() @auth_message = #client_signature = client_signature() proof = Base64.strict_encode64(xor(client_key, client_signature)) client_final = BSON::Binary.new ( client_final_wo_proof + ",p=#{proof}") client_final_msg = CLIENT_FINAL_MESSAGE.merge({PAYLOAD => client_final, conversationId: conv_id}) client_final_resp = @db.collection(SYSTEM_COMMAND_COLLECTION).first(client_final_msg) client_final_resp.callback do |res_final| if not is_server_response_valid? res_final response.fail "Final Server Response not valid " + res_final.to_s else server_final = res_final[PAYLOAD].to_s # in RFC this equals server_final verifier = server_final.match(VERIFIER)[1] #r= ... if verifier and verifier_valid? verifier handle_server_end(response,conv_id) # will set the response else response.fail "verifier #{verifier.nil? ? 'not present':'invalid'} #{res_final}" end end end client_final_resp.errback { |err| response.fail err } end end end client_first_resp.errback { |err| response.fail err } return response end |
#client_key ⇒ Object
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# File 'lib/em-mongo/auth/scram.rb', line 214 def client_key @client_key ||= hmac(salted_password,CLIENT_KEY) end |
#client_nonce ⇒ Object
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# File 'lib/em-mongo/auth/scram.rb', line 199 def client_nonce @client_nonce ||= SecureRandom.base64 end |
#client_signature ⇒ Object
needs @username, @plain_password, @salt, @iterations, @auth_message defined
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# File 'lib/em-mongo/auth/scram.rb', line 223 def client_signature @client_signature ||= hmac(DIGEST.digest(client_key), @auth_message) end |
#handle_server_end(response, conv_id) ⇒ Object
MongoDB handles the end of authentication different than in RFC 5802 it needs at least an additional empty response (this needs to be iterated until res=true
(at least it is done so in the official mongo-ruby-drive (at least it is done so in the official mongo-ruby-driver))
-> recursion (is technically more loop than recursion but here it's one)
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# File 'lib/em-mongo/auth/scram.rb', line 125 def handle_server_end(response,conv_id) # will set the response client_end = BSON::Binary.new('') client_end_msg = CLIENT_EMPTY_MESSAGE.merge(PAYLOAD=>client_end, conversationId:conv_id) server_end_resp = @db.collection(SYSTEM_COMMAND_COLLECTION).first(client_end_msg) server_end_resp.errback{|err| response.fail err} server_end_resp.callback do |res| if not is_server_response_valid? res response.fail "got invalid response on handling server_end: #{res.nil? ? 'nil' : res}" else if res['done'] == true || res['done'] == 'true' response.succeed true else handle_server_end(response,conv_id) # try it again end end end end |
#hashed_password ⇒ Object
needs @username, @plain_password defined
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# File 'lib/em-mongo/auth/scram.rb', line 204 def hashed_password @hashed_password ||= Support.hash_password(@username, @plain_password).encode("UTF-8") end |
#hi(password, salt, iterations) ⇒ Object
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# File 'lib/em-mongo/auth/scram.rb', line 177 def hi(password, salt, iterations) OpenSSL::PKCS5.pbkdf2_hmac_sha1( password, Base64.strict_decode64(salt), iterations, DIGEST.size ) end |
#hmac(data, key) ⇒ Object
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# File 'lib/em-mongo/auth/scram.rb', line 186 def hmac(data,key) OpenSSL::HMAC.digest(DIGEST, data, key) end |
#is_server_response_valid?(response) ⇒ Boolean
to be valid the response has to
* be not nil
* contain at least ['done'], ['ok'], ['payload'], ['conversationId']
* ['ok'].to_i has to be 1
* ['conversationId'] has to match the first sent one
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# File 'lib/em-mongo/auth/scram.rb', line 151 def is_server_response_valid?(response) if response.nil? then return false; end if response['done'].nil? or response['ok'].nil? or response['payload'].nil? or response['conversationId'].nil? then return false; end if not Support.ok? response then return false; end if not @conversation_id.nil? and response['conversationId'] != @conversation_id return false; end true end |
#salted_password ⇒ Object
needs @username, @plain_password, @salt, @iterations defined
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# File 'lib/em-mongo/auth/scram.rb', line 209 def salted_password @salted_password ||= hi(hashed_password, @salt, @iterations) end |
#server_key ⇒ Object
server_key = hmac(salted_password,“Server Key”)
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# File 'lib/em-mongo/auth/scram.rb', line 218 def server_key @server_key ||= hmac(salted_password,SERVER_KEY) end |
#server_signature ⇒ Object
server_signature = B64(hmac(server_key, auth_message)
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# File 'lib/em-mongo/auth/scram.rb', line 228 def server_signature @server_signature ||= Base64.strict_encode64(hmac(server_key, @auth_message)) end |
#verifier_valid?(verifier) ⇒ Boolean
verify the verifier (v=…)
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# File 'lib/em-mongo/auth/scram.rb', line 169 def verifier_valid?(verifier) verifier == server_signature end |
#xor(first, second) ⇒ Object
xor for strings
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# File 'lib/em-mongo/auth/scram.rb', line 191 def xor(first, second) first.bytes .zip(second.bytes) .map{|(x,y)| (x ^ y).chr} .join('') end |