X-Git-Url: https://git.enpas.org/?a=blobdiff_plain;f=util%2Fsasl%2Fscram.lua;h=cf2f0ede940c3e8eb3696192487efe2b80848c9d;hb=082e265af83ea25d8203d12114c6cf1b5cef810a;hp=1340423cd932e3d3ae1117dd57bdb2ba80bd2e26;hpb=bca1a48421947ca7d627c23433effed81a1d91f2;p=prosody.git diff --git a/util/sasl/scram.lua b/util/sasl/scram.lua index 1340423c..cf2f0ede 100644 --- a/util/sasl/scram.lua +++ b/util/sasl/scram.lua @@ -15,19 +15,21 @@ local s_match = string.match; local type = type local string = string local base64 = require "util.encodings".base64; -local hmac_sha1 = require "util.hmac".sha1; +local hmac_sha1 = require "util.hashes".hmac_sha1; local sha1 = require "util.hashes".sha1; +local Hi = require "util.hashes".scram_Hi_sha1; local generate_uuid = require "util.uuid".generate; local saslprep = require "util.encodings".stringprep.saslprep; +local nodeprep = require "util.encodings".stringprep.nodeprep; local log = require "util.logger".init("sasl"); local t_concat = table.concat; local char = string.char; local byte = string.byte; -module "scram" +module "sasl.scram" --========================= ---SASL SCRAM-SHA-1 according to draft-ietf-sasl-scram-10 +--SASL SCRAM-SHA-1 according to RFC 5802 --[[ Supported Authentication Backends @@ -35,7 +37,7 @@ Supported Authentication Backends scram_{MECH}: -- MECH being a standard hash name (like those at IANA's hash registry) with '-' replaced with '_' function(username, realm) - return salted_password, iteration_count, salt, state; + return stored_key, server_key, iteration_count, salt, state; end ]] @@ -64,51 +66,43 @@ local function binaryXOR( a, b ) return t_concat(result); end --- hash algorithm independent Hi(PBKDF2) implementation -local function Hi(hmac, str, salt, i) - local Ust = hmac(str, salt.."\0\0\0\1"); - local res = Ust; - for n=1,i-1 do - local Und = hmac(str, Ust) - res = binaryXOR(res, Und) - Ust = Und - end - return res -end - -local function validate_username(username) +local function validate_username(username, _nodeprep) -- check for forbidden char sequences for eq in username:gmatch("=(.?.?)") do - if eq ~= "2D" and eq ~= "3D" then - return false - end + if eq ~= "2C" and eq ~= "3D" then + return false + end end - -- replace =2D with , and =3D with = - username = username:gsub("=2D", ","); + -- replace =2C with , and =3D with = + username = username:gsub("=2C", ","); username = username:gsub("=3D", "="); -- apply SASLprep username = saslprep(username); - return username; + + if username and _nodeprep ~= false then + username = (_nodeprep or nodeprep)(username); + end + + return username and #username>0 and username; end -local function hashprep( hashname ) - local hash = hashname:lower() - hash = hash:gsub("-", "_") - return hash +local function hashprep(hashname) + return hashname:lower():gsub("-", "_"); end -function saltedPasswordSHA1(password, salt, iteration_count) - local salted_password +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.") end - - return true, Hi(hmac_sha1, password, salt, iteration_count); + 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) @@ -134,7 +128,7 @@ local function scram_gen(hash_name, H_f, HMAC_f) return "failure", "malformed-request", "Channel binding isn't support at this time."; end - self.state.name = validate_username(self.state.name); + self.state.name = validate_username(self.state.name, self.profile.nodeprep); if not self.state.name then log("debug", "Username violates either SASLprep or contains forbidden character sequences.") return "failure", "malformed-request", "Invalid username."; @@ -144,7 +138,7 @@ local function scram_gen(hash_name, H_f, HMAC_f) -- retreive credentials if self.profile.plain then - local password, state = self.profile.plain(self.state.name, self.realm) + local password, state = self.profile.plain(self, self.state.name, self.realm) if state == nil then return "failure", "not-authorized" elseif state == false then return "failure", "account-disabled" end @@ -158,17 +152,18 @@ local function scram_gen(hash_name, H_f, HMAC_f) self.state.iteration_count = default_i; local succ = false; - succ, self.state.salted_password = saltedPasswordSHA1(password, self.state.salt, default_i, self.state.iteration_count); + succ, self.state.stored_key, self.state.server_key = getAuthenticationDatabaseSHA1(password, self.state.salt, default_i, self.state.iteration_count); if not succ then - log("error", "Generating salted password failed. Reason: %s", self.state.salted_password); + log("error", "Generating authentication database failed. Reason: %s", self.state.stored_key); return "failure", "temporary-auth-failure"; end elseif self.profile["scram_"..hashprep(hash_name)] then - local salted_password, iteration_count, salt, state = self.profile["scram_"..hashprep(hash_name)](self.state.name, self.realm); + local stored_key, server_key, iteration_count, salt, state = self.profile["scram_"..hashprep(hash_name)](self, self.state.name, self.realm); if state == nil then return "failure", "not-authorized" elseif state == false then return "failure", "account-disabled" end - self.state.salted_password = salted_password; + self.state.stored_key = stored_key; + self.state.server_key = server_key; self.state.iteration_count = iteration_count; self.state.salt = salt end @@ -190,16 +185,15 @@ local function scram_gen(hash_name, H_f, HMAC_f) return "failure", "malformed-request", "Wrong nonce in client-final-message."; end - local SaltedPassword = self.state.salted_password; - local ClientKey = HMAC_f(SaltedPassword, "Client Key") - local ServerKey = HMAC_f(SaltedPassword, "Server Key") - local StoredKey = H_f(ClientKey) + local ServerKey = self.state.server_key; + local StoredKey = self.state.stored_key; + local AuthMessage = "n=" .. s_match(self.state.client_first_message,"n=(.+)") .. "," .. self.state.server_first_message .. "," .. s_match(client_final_message, "(.+),p=.+") local ClientSignature = HMAC_f(StoredKey, AuthMessage) - local ClientProof = binaryXOR(ClientKey, ClientSignature) + local ClientKey = binaryXOR(ClientSignature, base64.decode(self.state.proof)) local ServerSignature = HMAC_f(ServerKey, AuthMessage) - if base64.encode(ClientProof) == self.state.proof then + if StoredKey == H_f(ClientKey) then local server_final_message = "v="..base64.encode(ServerSignature); self["username"] = self.state.name; return "success", server_final_message;