diff options
Diffstat (limited to 'util/sasl')
-rw-r--r-- | util/sasl/digest-md5.lua | 251 | ||||
-rw-r--r-- | util/sasl/scram.lua | 53 |
2 files changed, 32 insertions, 272 deletions
diff --git a/util/sasl/digest-md5.lua b/util/sasl/digest-md5.lua deleted file mode 100644 index 7542a037..00000000 --- a/util/sasl/digest-md5.lua +++ /dev/null @@ -1,251 +0,0 @@ --- sasl.lua v0.4 --- Copyright (C) 2008-2010 Tobias Markmann --- --- All rights reserved. --- --- Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: --- --- * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. --- * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. --- * Neither the name of Tobias Markmann nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. --- --- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -local tostring = tostring; -local type = type; - -local s_gmatch = string.gmatch; -local s_match = string.match; -local t_concat = table.concat; -local t_insert = table.insert; -local to_byte, to_char = string.byte, string.char; - -local md5 = require "util.hashes".md5; -local log = require "util.logger".init("sasl"); -local generate_uuid = require "util.uuid".generate; -local nodeprep = require "util.encodings".stringprep.nodeprep; - -local _ENV = nil; --- luacheck: std none - ---========================= ---SASL DIGEST-MD5 according to RFC 2831 - ---[[ -Supported Authentication Backends - -digest_md5: - function(username, domain, realm, encoding) -- domain and realm are usually the same; for some broken - -- implementations it's not - return digesthash, state; - end - -digest_md5_test: - function(username, domain, realm, encoding, digesthash) - return true or false, state; - end -]] - -local function digest(self, message) - --TODO complete support for authzid - - local function serialize(message) - local data = "" - - -- testing all possible values - if message["realm"] then data = data..[[realm="]]..message.realm..[[",]] end - if message["nonce"] then data = data..[[nonce="]]..message.nonce..[[",]] end - if message["qop"] then data = data..[[qop="]]..message.qop..[[",]] end - if message["charset"] then data = data..[[charset=]]..message.charset.."," end - if message["algorithm"] then data = data..[[algorithm=]]..message.algorithm.."," end - if message["rspauth"] then data = data..[[rspauth=]]..message.rspauth.."," end - data = data:gsub(",$", "") - return data - end - - local function utf8tolatin1ifpossible(passwd) - local i = 1; - while i <= #passwd do - local passwd_i = to_byte(passwd:sub(i, i)); - if passwd_i > 0x7F then - if passwd_i < 0xC0 or passwd_i > 0xC3 then - return passwd; - end - i = i + 1; - passwd_i = to_byte(passwd:sub(i, i)); - if passwd_i < 0x80 or passwd_i > 0xBF then - return passwd; - end - end - i = i + 1; - end - - local p = {}; - local j = 0; - i = 1; - while (i <= #passwd) do - local passwd_i = to_byte(passwd:sub(i, i)); - if passwd_i > 0x7F then - i = i + 1; - local passwd_i_1 = to_byte(passwd:sub(i, i)); - t_insert(p, to_char(passwd_i%4*64 + passwd_i_1%64)); -- I'm so clever - else - t_insert(p, to_char(passwd_i)); - end - i = i + 1; - end - return t_concat(p); - end - local function latin1toutf8(str) - local p = {}; - for ch in s_gmatch(str, ".") do - ch = to_byte(ch); - if (ch < 0x80) then - t_insert(p, to_char(ch)); - elseif (ch < 0xC0) then - t_insert(p, to_char(0xC2, ch)); - else - t_insert(p, to_char(0xC3, ch - 64)); - end - end - return t_concat(p); - end - local function parse(data) - local message = {} - -- COMPAT: %z in the pattern to work around jwchat bug (sends "charset=utf-8\0") - for k, v in s_gmatch(data, [[([%w%-]+)="?([^",%z]*)"?,?]]) do -- FIXME The hacky regex makes me shudder - message[k] = v; - end - return message; - end - - if not self.nonce then - self.nonce = generate_uuid(); - self.step = 0; - self.nonce_count = {}; - end - - self.step = self.step + 1; - if (self.step == 1) then - local challenge = serialize({ nonce = self.nonce, - qop = "auth", - charset = "utf-8", - algorithm = "md5-sess", - realm = self.realm}); - return "challenge", challenge; - elseif (self.step == 2) then - local response = parse(message); - -- check for replay attack - if response["nc"] then - if self.nonce_count[response["nc"]] then return "failure", "not-authorized" end - end - - -- check for username, it's REQUIRED by RFC 2831 - local username = response["username"]; - local _nodeprep = self.profile.nodeprep; - if username and _nodeprep ~= false then - username = (_nodeprep or nodeprep)(username); -- FIXME charset - end - if not username or username == "" then - return "failure", "malformed-request"; - end - self.username = username; - - -- check for nonce, ... - if not response["nonce"] then - return "failure", "malformed-request"; - else - -- check if it's the right nonce - if response["nonce"] ~= tostring(self.nonce) then return "failure", "malformed-request" end - end - - if not response["cnonce"] then return "failure", "malformed-request", "Missing entry for cnonce in SASL message." end - if not response["qop"] then response["qop"] = "auth" end - - if response["realm"] == nil or response["realm"] == "" then - response["realm"] = ""; - elseif response["realm"] ~= self.realm then - return "failure", "not-authorized", "Incorrect realm value"; - end - - local decoder; - if response["charset"] == nil then - decoder = utf8tolatin1ifpossible; - elseif response["charset"] ~= "utf-8" then - return "failure", "incorrect-encoding", "The client's response uses "..response["charset"].." for encoding with isn't supported by sasl.lua. Supported encodings are latin or utf-8."; - end - - local domain = ""; - local protocol = ""; - if response["digest-uri"] then - protocol, domain = response["digest-uri"]:match("(%w+)/(.*)$"); - if protocol == nil or domain == nil then return "failure", "malformed-request" end - else - return "failure", "malformed-request", "Missing entry for digest-uri in SASL message." - end - - --TODO maybe realm support - local Y, state; - if self.profile.plain then - local password, state = self.profile.plain(self, response["username"], self.realm) - if state == nil then return "failure", "not-authorized" - elseif state == false then return "failure", "account-disabled" end - Y = md5(response["username"]..":"..response["realm"]..":"..password); - elseif self.profile["digest-md5"] then - Y, state = self.profile["digest-md5"](self, response["username"], self.realm, response["realm"], response["charset"]) - if state == nil then return "failure", "not-authorized" - elseif state == false then return "failure", "account-disabled" end - elseif self.profile["digest-md5-test"] then - -- TODO - end - --local password_encoding, Y = self.credentials_handler("DIGEST-MD5", response["username"], self.realm, response["realm"], decoder); - --if Y == nil then return "failure", "not-authorized" - --elseif Y == false then return "failure", "account-disabled" end - local A1 = ""; - if response.authzid then - if response.authzid == self.username or response.authzid == self.username.."@"..self.realm then - -- COMPAT - log("warn", "Client is violating RFC 3920 (section 6.1, point 7)."); - A1 = Y..":"..response["nonce"]..":"..response["cnonce"]..":"..response.authzid; - else - return "failure", "invalid-authzid"; - end - else - A1 = Y..":"..response["nonce"]..":"..response["cnonce"]; - end - local A2 = "AUTHENTICATE:"..protocol.."/"..domain; - - local HA1 = md5(A1, true); - local HA2 = md5(A2, true); - - local KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2; - local response_value = md5(KD, true); - - if response_value == response["response"] then - -- calculate rspauth - A2 = ":"..protocol.."/"..domain; - - HA1 = md5(A1, true); - HA2 = md5(A2, true); - - KD = HA1..":"..response["nonce"]..":"..response["nc"]..":"..response["cnonce"]..":"..response["qop"]..":"..HA2 - local rspauth = md5(KD, true); - self.authenticated = true; - --TODO: considering sending the rspauth in a success node for saving one roundtrip; allowed according to http://tools.ietf.org/html/draft-saintandre-rfc3920bis-09#section-7.3.6 - return "challenge", serialize({rspauth = rspauth}); - else - return "failure", "not-authorized", "The response provided by the client doesn't match the one we calculated." - end - elseif self.step == 3 then - if self.authenticated ~= nil then return "success" - else return "failure", "malformed-request" end - end -end - -local function init(registerMechanism) - registerMechanism("DIGEST-MD5", {"plain"}, digest); -end - -return { - init = init; -} diff --git a/util/sasl/scram.lua b/util/sasl/scram.lua index 043f328b..b3370d4b 100644 --- a/util/sasl/scram.lua +++ b/util/sasl/scram.lua @@ -14,9 +14,7 @@ local s_match = string.match; local type = type local base64 = require "util.encodings".base64; -local hmac_sha1 = require "util.hashes".hmac_sha1; -local sha1 = require "util.hashes".sha1; -local Hi = require "util.hashes".scram_Hi_sha1; +local hashes = require "util.hashes"; local generate_uuid = require "util.uuid".generate; local saslprep = require "util.encodings".stringprep.saslprep; local nodeprep = require "util.encodings".stringprep.nodeprep; @@ -99,20 +97,22 @@ local function hashprep(hashname) return hashname:lower():gsub("-", "_"); end -local function getAuthenticationDatabaseSHA1(password, salt, iteration_count) - if type(password) ~= "string" or type(salt) ~= "string" or type(iteration_count) ~= "number" then - return false, "inappropriate argument types" - end - if iteration_count < 4096 then - log("warn", "Iteration count < 4096 which is the suggested minimum according to RFC 5802.") +local function get_scram_hasher(H, HMAC, Hi) + return function (password, salt, iteration_count) + if type(password) ~= "string" or type(salt) ~= "string" or type(iteration_count) ~= "number" then + return false, "inappropriate argument types" + end + if iteration_count < 4096 then + log("warn", "Iteration count < 4096 which is the suggested minimum according to RFC 5802.") + end + local salted_password = Hi(password, salt, iteration_count); + local stored_key = H(HMAC(salted_password, "Client Key")) + local server_key = HMAC(salted_password, "Server Key"); + return true, stored_key, server_key end - local salted_password = Hi(password, salt, iteration_count); - local stored_key = sha1(hmac_sha1(salted_password, "Client Key")) - local server_key = hmac_sha1(salted_password, "Server Key"); - return true, stored_key, server_key end -local function scram_gen(hash_name, H_f, HMAC_f) +local function scram_gen(hash_name, H_f, HMAC_f, get_auth_db, expect_cb) local profile_name = "scram_" .. hashprep(hash_name); local function scram_hash(self, message) local support_channel_binding = false; @@ -125,6 +125,7 @@ local function scram_gen(hash_name, H_f, HMAC_f) local client_first_message = message; -- TODO: fail if authzid is provided, since we don't support them yet + -- luacheck: ignore 211/authzid local gs2_header, gs2_cbind_flag, gs2_cbind_name, authzid, client_first_message_bare, username, clientnonce = s_match(client_first_message, "^(([pny])=?([^,]*),([^,]*),)(m?=?[^,]*,?n=([^,]*),r=([^,]*),?.*)$"); @@ -140,6 +141,10 @@ local function scram_gen(hash_name, H_f, HMAC_f) if gs2_cbind_flag == "n" then -- "n" -> client doesn't support channel binding. + if expect_cb then + log("debug", "Client unexpectedly doesn't support channel binding"); + -- XXX Is it sensible to abort if the client starts -PLUS but doesn't use channel binding? + end support_channel_binding = false; end @@ -177,7 +182,7 @@ local function scram_gen(hash_name, H_f, HMAC_f) iteration_count = default_i; local succ; - succ, stored_key, server_key = getAuthenticationDatabaseSHA1(password, salt, iteration_count); + succ, stored_key, server_key = get_auth_db(password, salt, iteration_count); if not succ then log("error", "Generating authentication database failed. Reason: %s", stored_key); return "failure", "temporary-auth-failure"; @@ -190,7 +195,7 @@ local function scram_gen(hash_name, H_f, HMAC_f) end local nonce = clientnonce .. generate_uuid(); - local server_first_message = "r="..nonce..",s="..base64.encode(salt)..",i="..iteration_count; + local server_first_message = ("r=%s,s=%s,i=%d"):format(nonce, base64.encode(salt), iteration_count); self.state = { gs2_header = gs2_header; gs2_cbind_name = gs2_cbind_name; @@ -247,22 +252,28 @@ local function scram_gen(hash_name, H_f, HMAC_f) return scram_hash; end +local auth_db_getters = {} local function init(registerMechanism) - local function registerSCRAMMechanism(hash_name, hash, hmac_hash) + local function registerSCRAMMechanism(hash_name, hash, hmac_hash, pbkdf2) + local get_auth_db = get_scram_hasher(hash, hmac_hash, pbkdf2); + auth_db_getters[hash_name] = get_auth_db; registerMechanism("SCRAM-"..hash_name, {"plain", "scram_"..(hashprep(hash_name))}, - scram_gen(hash_name:lower(), hash, hmac_hash)); + scram_gen(hash_name:lower(), hash, hmac_hash, get_auth_db)); -- register channel binding equivalent registerMechanism("SCRAM-"..hash_name.."-PLUS", {"plain", "scram_"..(hashprep(hash_name))}, - scram_gen(hash_name:lower(), hash, hmac_hash), {"tls-unique"}); + scram_gen(hash_name:lower(), hash, hmac_hash, get_auth_db, true), {"tls-unique"}); end - registerSCRAMMechanism("SHA-1", sha1, hmac_sha1); + registerSCRAMMechanism("SHA-1", hashes.sha1, hashes.hmac_sha1, hashes.pbkdf2_hmac_sha1); + registerSCRAMMechanism("SHA-256", hashes.sha256, hashes.hmac_sha256, hashes.pbkdf2_hmac_sha256); end return { - getAuthenticationDatabaseSHA1 = getAuthenticationDatabaseSHA1; + get_hash = get_scram_hasher; + hashers = auth_db_getters; + getAuthenticationDatabaseSHA1 = get_scram_hasher(hashes.sha1, hashes.hmac_sha1, hashes.pbkdf2_hmac_sha1); -- COMPAT init = init; } |