-- 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 s_match = string.match;
-
+local type = type
+local string = string
local base64 = require "util.encodings".base64;
local xor = require "bit".bxor
local hmac_sha1 = require "util.hmac".sha1;
local sha1 = require "util.hashes".sha1;
+local generate_uuid = require "util.uuid".generate;
+local saslprep = require "util.encodings".stringprep.saslprep;
+local log = require "util.logger".init("sasl");
-module "plain"
+module "scram"
--=========================
--SASL SCRAM-SHA-1 according to draft-ietf-sasl-scram-10
end
local function binaryXOR( a, b )
- if string.len(a) > string.len(b) then
+ if a:len() > b:len() then
b = string.rep("\0", a:len() - b:len())..b
elseif string.len(a) < string.len(b) then
a = string.rep("\0", b:len() - a:len())..a
local function validate_username(username)
-- check for forbidden char sequences
+ for eq in username:gmatch("=(.?.?)") do
+ if eq ~= "2D" and eq ~= "3D" then
+ return false
+ end
+ end
-- replace =2D with , and =3D with =
+ username:gsub("=2D", ",");
+ username:gsub("=3D", "=");
-- apply SASLprep
+ username = saslprep(username);
return username;
end
if not self.state.name then
-- we are processing client_first_message
- self.state["name"] = string.match(client_first_message, "n=(.+),r=")
- self.state["clientnonce"] = string.match(client_first_message, "r=([^,]+)")
+ local client_first_message = message;
+ self.state["client_first_message"] = client_first_message;
+ self.state["name"] = client_first_message:match("n=(.+),r=")
+ self.state["clientnonce"] = client_first_message:match("r=([^,]+)")
+
+ if not self.state.name or not self.state.clientnonce then
+ return "failure", "malformed-request";
+ end
self.state.name = validate_username(self.state.name);
if not self.state.name then
+ log("debug", "Username violates either SASLprep or contains forbidden character sequences.")
return "failure", "malformed-request";
end
+
+ self.state["servernonce"] = generate_uuid();
+ self.state["salt"] = generate_uuid();
+
+ local server_first_message = "r="..self.state.clientnonce..self.state.servernonce..",s="..base64.encode(self.state.salt)..",i="..default_i;
+ self.state["server_first_message"] = server_first_message;
+ return "challenge", server_first_message
else
+ if type(message) ~= "string" then return "failure", "malformed-request" end
-- we are processing client_final_message
+ local client_final_message = message;
+
+ self.state["proof"] = client_final_message:match("p=(.+)");
+ self.state["nonce"] = client_final_message:match("r=(.+),p=");
+ self.state["channelbinding"] = client_final_message:match("c=(.+),r=");
+ if not self.state.proof or not self.state.nonce or not self.state.channelbinding then
+ return "failure", "malformed-request";
+ end
+
+ local password;
+ if self.profile.plain then
+ password, state = self.profile.plain(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.");
+ return "failure", "not-authorized"
+ end
+ end
+
+ local SaltedPassword = Hi(hmac_sha1, password, self.state.salt, default_i)
+ local ClientKey = hmac_sha1(SaltedPassword, "Client Key")
+ local ServerKey = hmac_sha1(SaltedPassword, "Server Key")
+ local StoredKey = sha1(ClientKey)
+ 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_sha1(StoredKey, AuthMessage)
+ local ClientProof = binaryXOR(ClientKey, ClientSignature)
+ local ServerSignature = hmac_sha1(ServerKey, AuthMessage)
+
+ if base64.encode(ClientProof) == self.state.proof then
+ local server_final_message = "v="..base64.encode(ServerSignature);
+ self["username"] = self.state.name;
+ return "success", server_final_message;
+ else
+ return "failure", "not-authorized", "The response provided by the client doesn't match the one we calculated.";
+ end
end
end
projects / prosody.git / blobdiff