/* 
   Unix SMB/CIFS implementation.

   Do a netr_LogonSamLogon to a remote DC

   Copyright (C) Volker Lendecke 2005
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
   Copyright (C) Stefan Metzmacher 2006
   
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"
#include "libcli/composite/composite.h"
#include "winbind/wb_server.h"
#include "smbd/service_task.h"
#include "libcli/auth/credentials.h"
#include "libcli/auth/libcli_auth.h"
#include "librpc/gen_ndr/ndr_netlogon.h"
#include "librpc/gen_ndr/ndr_netlogon_c.h"
#include "librpc/gen_ndr/winbind.h"

struct wb_sam_logon_state {
	struct composite_context *ctx;

	struct winbind_SamLogon *req;

        struct creds_CredentialState *creds_state;
        struct netr_Authenticator auth1, auth2;

	TALLOC_CTX *r_mem_ctx;
        struct netr_LogonSamLogon r;
};

static void wb_sam_logon_recv_domain(struct composite_context *ctx);
static void wb_sam_logon_recv_samlogon(struct rpc_request *req);

/*
    Find the connection to the DC (or find an existing connection)
*/
struct composite_context *wb_sam_logon_send(TALLOC_CTX *mem_ctx,
					    struct wbsrv_service *service,
					    struct winbind_SamLogon *req)
{
	struct composite_context *c, *creq;
	struct wb_sam_logon_state *s;

	c = composite_create(mem_ctx, service->task->event_ctx);
	if (!c) return NULL;

	s = talloc_zero(c, struct wb_sam_logon_state);
	if (composite_nomem(s, c)) return c;
	s->ctx = c;
	s->req = req;

	c->private_data = s;

	creq = wb_sid2domain_send(s, service, service->primary_sid);
	composite_continue(c, creq, wb_sam_logon_recv_domain, s);
	return c;
}

/*
    Finish the connection to the DC
    Send of a SamLogon request to authenticate a user.
*/
static void wb_sam_logon_recv_domain(struct composite_context *creq)
{
	struct wb_sam_logon_state *s = talloc_get_type(creq->async.private_data,
				       struct wb_sam_logon_state);
	struct rpc_request *req;
	struct wbsrv_domain *domain;

	s->ctx->status = wb_sid2domain_recv(creq, &domain);
	if (!composite_is_ok(s->ctx)) return;

	s->creds_state = cli_credentials_get_netlogon_creds(domain->schannel_creds);
	creds_client_authenticator(s->creds_state, &s->auth1);

	s->r.in.server_name = talloc_asprintf(s, "\\\\%s",
			      dcerpc_server_name(domain->netlogon_pipe));
	if (composite_nomem(s->r.in.server_name, s->ctx)) return;

	s->r.in.computer_name = cli_credentials_get_workstation(domain->schannel_creds);
	s->r.in.credential = &s->auth1;
	s->r.in.return_authenticator = &s->auth2;
	s->r.in.logon_level = s->req->in.logon_level;
	s->r.in.logon = s->req->in.logon;
	s->r.in.validation_level = s->req->in.validation_level;
	s->r.out.return_authenticator = NULL;

	/*
	 * use a new talloc context for the LogonSamLogon call
	 * because then we can just to a talloc_steal on this context
	 * in the final _recv() function to give the caller all the content of
	 * the s->r.out.validation
	 */
	s->r_mem_ctx = talloc_new(s);
	if (composite_nomem(s->r_mem_ctx, s->ctx)) return;

	req = dcerpc_netr_LogonSamLogon_send(domain->netlogon_pipe, s->r_mem_ctx, &s->r);
	composite_continue_rpc(s->ctx, req, wb_sam_logon_recv_samlogon, s);
}

/* 
   NTLM Authentication 
   
   Check the SamLogon reply and decrypt the session keys
*/
static void wb_sam_logon_recv_samlogon(struct rpc_request *req)
{
	struct wb_sam_logon_state *s = talloc_get_type(req->async.private,
				       struct wb_sam_logon_state);

	s->ctx->status = dcerpc_ndr_request_recv(req);
	if (!composite_is_ok(s->ctx)) return;

	s->ctx->status = s->r.out.result;
	if (!composite_is_ok(s->ctx)) return;

	if ((s->r.out.return_authenticator == NULL) ||
	    (!creds_client_check(s->creds_state,
				 &s->r.out.return_authenticator->cred))) {
		DEBUG(0, ("Credentials check failed!\n"));
		composite_error(s->ctx, NT_STATUS_ACCESS_DENIED);
		return;
	}

	/* Decrypt the session keys before we reform the info3, so the
	 * person on the other end of winbindd pipe doesn't have to.
	 * They won't have the encryption key anyway */
	creds_decrypt_samlogon(s->creds_state,
			       s->r.in.validation_level,
			       &s->r.out.validation);

	composite_done(s->ctx);
}

NTSTATUS wb_sam_logon_recv(struct composite_context *c,
			   TALLOC_CTX *mem_ctx,
			   struct winbind_SamLogon *req)
{
	struct wb_sam_logon_state *s = talloc_get_type(c->private_data,
				       struct wb_sam_logon_state);
	NTSTATUS status = composite_wait(c);

	if (NT_STATUS_IS_OK(status)) {
		talloc_steal(mem_ctx, s->r_mem_ctx);
		req->out.validation	= s->r.out.validation;
		req->out.authoritative	= 1;
		req->out.flags		= 0;
	}

	talloc_free(s);
	return status;
}