diff options
Diffstat (limited to 'util/sasl/scram.lua')
| -rw-r--r-- | util/sasl/scram.lua | 63 |
1 files changed, 29 insertions, 34 deletions
diff --git a/util/sasl/scram.lua b/util/sasl/scram.lua index 071de505..cf938dba 100644 --- a/util/sasl/scram.lua +++ b/util/sasl/scram.lua @@ -16,16 +16,18 @@ local type = type local string = string local tostring = tostring; 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 RFC 5802 @@ -69,33 +71,26 @@ local function binaryXOR( a, b ) return t_concat(result); end --- hash algorithm independent Hi(PBKDF2) implementation -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 + 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) @@ -109,7 +104,7 @@ function getAuthenticationDatabaseSHA1(password, salt, iteration_count) if iteration_count < 4096 then log("warn", "Iteration count < 4096 which is the suggested minimum according to RFC 5802.") end - local salted_password = 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 @@ -120,12 +115,12 @@ local function scram_gen(hash_name, H_f, HMAC_f) if not self.state then self["state"] = {} end local support_channel_binding = false; if self.profile.cb then support_channel_binding = true; end - + if type(message) ~= "string" or #message == 0 then return "failure", "malformed-request" end if not self.state.name then -- we are processing client_first_message local client_first_message = message; - log("debug", client_first_message); + -- TODO: fail if authzid is provided, since we don't support them yet self.state["client_first_message"] = client_first_message; self.state["gs2_cbind_flag"], self.state["gs2_cbind_name"], self.state["authzid"], self.state["name"], self.state["clientnonce"] @@ -156,21 +151,21 @@ local function scram_gen(hash_name, H_f, HMAC_f) if not self.state.name or not self.state.clientnonce then 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."; end - + self.state["servernonce"] = generate_uuid(); - + -- retreive credentials if self.profile.plain then 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 - + password = saslprep(password); if not password then log("debug", "Password violates SASLprep."); @@ -190,20 +185,20 @@ local function scram_gen(hash_name, H_f, HMAC_f) 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.stored_key = stored_key; self.state.server_key = server_key; self.state.iteration_count = iteration_count; self.state.salt = salt end - + local server_first_message = "r="..self.state.clientnonce..self.state.servernonce..",s="..base64.encode(self.state.salt)..",i="..self.state.iteration_count; self.state["server_first_message"] = server_first_message; return "challenge", server_first_message else -- we are processing client_final_message local client_final_message = message; - log("debug", "client_final_message: %s", client_final_message); + self.state["channelbinding"], self.state["nonce"], self.state["proof"] = client_final_message:match("^c=(.*),r=(.*),.*p=(.*)"); if not self.state.proof or not self.state.nonce or not self.state.channelbinding then @@ -223,10 +218,10 @@ local function scram_gen(hash_name, H_f, HMAC_f) if self.state.nonce ~= self.state.clientnonce..self.state.servernonce then return "failure", "malformed-request", "Wrong nonce in client-final-message."; end - + 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 ClientKey = binaryXOR(ClientSignature, base64.decode(self.state.proof)) |