Add OAUTH SQL backend

sql/lite.sql

@@ -313,3 +313,10 @@ CREATE TABLE sm (
 CREATE UNIQUE INDEX i_sm_sid ON sm(usec, pid);
 CREATE INDEX i_sm_node ON sm(node);
 CREATE INDEX i_sm_username ON sm(username);
+
+CREATE TABLE oauth_token (
+    token text NOT NULL PRIMARY KEY,
+    jid text NOT NULL,
+    scope text NOT NULL,
+    expire bigint NOT NULL
+);

sql/mssql.sql

@@ -480,3 +480,13 @@ ON DELETE CASCADE;
 
 ALTER TABLE [dbo].[pubsub_state] CHECK CONSTRAINT [pubsub_state_ibfk_1];
 
+CREATE TABLE [dbo].[oauth_token] (
+    [token] [varchar] (250) NOT NULL,
+    [jid] [text] NOT NULL,
+    [scope] [text] NOT NULL,
+    [expire] [bigint] NOT NULL,
+ CONSTRAINT [oauth_token_PRIMARY] PRIMARY KEY CLUSTERED 
+(
+        [token] ASC
+)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON)
+) TEXTIMAGE_ON [PRIMARY];

sql/mysql.sql

@@ -328,3 +328,10 @@ CREATE TABLE sm (
 CREATE UNIQUE INDEX i_sid ON sm(usec, pid(75));
 CREATE INDEX i_node ON sm(node(75));
 CREATE INDEX i_username ON sm(username);
+
+CREATE TABLE oauth_token (
+    token varchar(191) NOT NULL PRIMARY KEY,
+    jid text NOT NULL,
+    scope text NOT NULL,
+    expire bigint NOT NULL
+) ENGINE=InnoDB CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;

sql/pg.sql

@@ -330,3 +330,12 @@ CREATE TABLE sm (
 CREATE UNIQUE INDEX i_sm_sid ON sm USING btree (usec, pid);
 CREATE INDEX i_sm_node ON sm USING btree (node);
 CREATE INDEX i_sm_username ON sm USING btree (username);
+
+CREATE TABLE oauth_token (
+    token text NOT NULL,
+    jid text NOT NULL,
+    scope text NOT NULL,
+    expire bigint NOT NULL
+);
+
+CREATE UNIQUE INDEX i_oauth_token_token ON oauth_token USING btree (token);

src/ejabberd_oauth_sql.erl

@@ -0,0 +1,78 @@
+%%%-------------------------------------------------------------------
+%%% File    : ejabberd_oauth_sql.erl
+%%% Author  : Alexey Shchepin <alexey@process-one.net>
+%%% Purpose : OAUTH2 SQL backend
+%%% Created : 27 Jul 2016 by Alexey Shchepin <alexey@process-one.net>
+%%%
+%%%
+%%% ejabberd, Copyright (C) 2002-2016   ProcessOne
+%%%
+%%% This program is free software; you can redistribute it and/or
+%%% modify it under the terms of the GNU General Public License as
+%%% published by the Free Software Foundation; either version 2 of the
+%%% License, or (at your option) any later version.
+%%%
+%%% This program is distributed in the hope that it will be useful,
+%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+%%% General Public License for more details.
+%%%
+%%% You should have received a copy of the GNU General Public License
+%%% along with this program; if not, write to the Free Software
+%%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+%%% 02111-1307 USA
+%%%
+%%%-------------------------------------------------------------------
+
+-module(ejabberd_oauth_sql).
+
+-compile([{parse_transform, ejabberd_sql_pt}]).
+
+-export([init/0,
+         store/1,
+         lookup/1,
+         clean/1]).
+
+-include("ejabberd_oauth.hrl").
+-include("ejabberd.hrl").
+-include("ejabberd_sql_pt.hrl").
+-include("jlib.hrl").
+
+init() ->
+    ok.
+
+store(R) ->
+    Token = R#oauth_token.token,
+    {User, Server} = R#oauth_token.us,
+    SJID = jid:to_string({User, Server, <<"">>}),
+    Scope = str:join(R#oauth_token.scope, <<" ">>),
+    Expire = R#oauth_token.expire,
+    ?SQL_UPSERT(
+       ?MYNAME,
+       "oauth_token",
+       ["!token=%(Token)s",
+        "jid=%(SJID)s",
+        "scope=%(Scope)s",
+        "expire=%(Expire)d"]).
+
+lookup(Token) ->
+    case ejabberd_sql:sql_query(
+           ?MYNAME,
+           ?SQL("select @(jid)s, @(scope)s, @(expire)d"
+                " from oauth_token where token=%(Token)s")) of
+        {selected, [{SJID, Scope, Expire}]} ->
+            JID = jid:from_string(SJID),
+            US = {JID#jid.luser, JID#jid.lserver},
+            #oauth_token{token = Token,
+                         us = US,
+                         scope = str:tokens(Scope, <<" ">>),
+                         expire = Expire};
+        _ ->
+            false
+    end.
+
+clean(TS) ->
+    ejabberd_sql:sql_query(
+      ?MYNAME,
+      ?SQL("delete from oauth_token where expire < %(TS)d")).
+