From 544ea51c3663070dadd588d9de3e22d6e045743e Mon Sep 17 00:00:00 2001
From: Kaarle Ritvanen <kaarle.ritvanen@datakunkku.fi>
Date: Wed, 27 Feb 2013 07:39:26 +0000
Subject: basic login session management

---
 LICENSE             |  2 +-
 acf/modules/aaa.lua |  3 ++-
 config/aaa.json     |  2 +-
 protocol.txt        | 10 +++++++
 server.lua          | 76 ++++++++++++++++++++++++++++++++++++++++++-----------
 5 files changed, 74 insertions(+), 19 deletions(-)

diff --git a/LICENSE b/LICENSE
index a0b36bf..da09525 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2012 Kaarle Ritvanen
+Copyright (c) 2012-2013 Kaarle Ritvanen
 
 All rights reserved.
 
diff --git a/acf/modules/aaa.lua b/acf/modules/aaa.lua
index f8e28ca..1704376 100644
--- a/acf/modules/aaa.lua
+++ b/acf/modules/aaa.lua
@@ -1,5 +1,5 @@
 --[[
-Copyright (c) 2012 Kaarle Ritvanen
+Copyright (c) 2012-2013 Kaarle Ritvanen
 See LICENSE file for license details
 --]]
 
@@ -14,6 +14,7 @@ User = M.new()
 User.password = M.String
 User.real_name = M.String
 User.roles = M.Collection{type=M.Reference{scope='../../roles'}}
+function User:check_password(password) return password == self.password end
 
 Authentication = M.new()
 Authentication.users = M.Collection{type=User}
diff --git a/config/aaa.json b/config/aaa.json
index 0967ef4..248bd32 100644
--- a/config/aaa.json
+++ b/config/aaa.json
@@ -1 +1 @@
-{}
+{"users":{"admin":{"password":"admin"}}}
\ No newline at end of file
diff --git a/protocol.txt b/protocol.txt
index 7e0f3c2..018006a 100644
--- a/protocol.txt
+++ b/protocol.txt
@@ -4,6 +4,16 @@ ACF2 HTTP Protocol
 Load JavaScript client:
 req: GET /
 
+Log in:
+req: POST /login
+     - body is a JSON object with username and password attributes
+resp: authentication token (in header as X-ACF-Auth-Token)
+      - use X-ACF-Auth-Token in the header of subsequent requests
+
+Log out:
+req: DELETE /login
+     X-ACF-Auth-Token: <token>
+
 Start transaction:
 req: POST /
 resp: txn ID (in header as X-ACF-Transaction-ID)
diff --git a/server.lua b/server.lua
index 11bfe55..c6fe586 100644
--- a/server.lua
+++ b/server.lua
@@ -1,5 +1,5 @@
 --[[
-Copyright (c) 2012 Kaarle Ritvanen
+Copyright (c) 2012-2013 Kaarle Ritvanen
 See LICENSE file for license details
 --]]
 
@@ -10,13 +10,7 @@ require 'json'
 require 'stringy'
 
 
-local function handle(env, txn, path)
-   local method = env.REQUEST_METHOD
-   local data
-   if env.CONTENT_LENGTH then
-      data = json.decode(env.input:read(env.CONTENT_LENGTH))
-   end
-
+local function handle(txn, method, path, data)
    local parent, name
    if path ~= '/' then
       parent = txn:search(acf.path.parent(path))
@@ -60,30 +54,80 @@ local function handle(env, txn, path)
 end
 
 
+-- TODO shared storage for login sessions
+local last_sid = 0
+local sessions = {}
+
 -- TODO implement transactions as threads or store their state in
 -- shared storage
-local last_id = 0
+local last_txn_id = 0
 local txns = {}
 
+-- TODO expire stale sessions and transactions
+
 
 return function(env)
 	  local method = env.REQUEST_METHOD
 	  local path = env.REQUEST_URI
 
-	  -- TODO login session management
+	  local data
+	  if env.CONTENT_LENGTH then
+	     data = json.decode(env.input:read(env.CONTENT_LENGTH))
+	  end
+
+	  local sid = tonumber(env.HTTP_X_ACF_AUTH_TOKEN)
+	  local user, txn_id
+	  if sid then
+	     user = sessions[sid]
+	     if not user then return 401 end
+	     txn_id = tonumber(env.HTTP_X_ACF_TRANSACTION_ID)
+	  end
 
-	  local txn_id = tonumber(env.HTTP_X_ACF_TRANSACTION_ID)
 	  local txn
 	  if txn_id then
 	     txn = txns[txn_id]
 	     if not txn then return 404 end
 	  else txn = acf.transaction.start() end
 
+	  local function fetch_user(name)
+	     user = name and txn:search('/auth/users')[name]
+	  end
+	  if user then
+	     fetch_user(user)
+	     if not user then return 401 end
+	  end
+
+	  if path == '/login' then
+	     if method == 'POST' then
+		if not data.username or not data.password then return 401 end
+		fetch_user(data.username)
+		if user and user:check_password(data.password) then
+		   last_sid = last_sid + 1
+		   local sid = last_sid
+		   sessions[sid] = data.username
+		   return 200, {['X-ACF-Auth-Token']=sid}
+		end
+		return 401
+	     end
+
+	     if not user then return 401 end
+
+	     if method == 'DELETE' then
+		sessions[sid] = nil
+		return 200
+	     end
+
+	     return 405
+	  end
+
+	  if not user then return 401 end
+
 	  if stringy.startswith(path, '/config/') then
 	     -- TODO catch and forward relevant errors to the client
-	     local code, hdr, body = handle(env,
-					    txn,
-					    string.sub(path, 8, -1))
+	     local code, hdr, body = handle(txn,
+					    method,
+					    string.sub(path, 8, -1),
+					    data)
 	     if not txn_id and method ~= 'GET' and code == 200 then
 		txn:commit()
 	     end
@@ -105,8 +149,8 @@ return function(env)
 
 	     if method == 'DELETE' then return 405 end
 
-	     last_id = last_id + 1
-	     local txn_id = last_id
+	     last_txn_id = last_txn_id + 1
+	     local txn_id = last_txn_id
 	     txns[txn_id] = txn
 	     return 200, {['X-ACF-Transaction-ID']=txn_id}
 	  end
-- 
cgit v1.2.3