/* 
   Unix SMB/CIFS implementation.

   Copyright (C) Rafal Szczesniak 2005
   
   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.
*/

/*
  a composite functions for user management operations (add/del/chg)
*/

#include "includes.h"
#include "libcli/composite/composite.h"
#include "libnet/composite.h"
#include "libnet/userman.h"
#include "libnet/userinfo.h"
#include "librpc/gen_ndr/ndr_samr_c.h"

/*
 * Composite USER ADD functionality
 */

static void useradd_handler(struct rpc_request*);

enum useradd_stage { USERADD_CREATE };

struct useradd_state {
	enum useradd_stage       stage;
	struct dcerpc_pipe       *pipe;
	struct rpc_request       *req;
	struct policy_handle     domain_handle;
	struct samr_CreateUser   createuser;
	struct policy_handle     user_handle;
	uint32_t                 user_rid;

	/* information about the progress */
	void (*monitor_fn)(struct monitor_msg *);
};


/**
 * Stage 1 (and the only one for now): Create user account.
 */
static NTSTATUS useradd_create(struct composite_context *c,
			       struct useradd_state *s)
{
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);
	
	c->state = COMPOSITE_STATE_DONE;
	return NT_STATUS_OK;
}


/**
 * Event handler for asynchronous request. Handles transition through
 * intermediate stages of the call.
 *
 * @param req rpc call context
 */
static void useradd_handler(struct rpc_request *req)
{
	struct composite_context *c = req->async.private;
	struct useradd_state *s = talloc_get_type(c->private_data, struct useradd_state);
	struct monitor_msg msg;
	struct msg_rpc_create_user *rpc_create;
	
	switch (s->stage) {
	case USERADD_CREATE:
		c->status = useradd_create(c, s);
		
		/* prepare a message to pass to monitor function */
		msg.type = rpc_create_user;
		rpc_create = talloc(s, struct msg_rpc_create_user);
		rpc_create->rid = *s->createuser.out.rid;
		msg.data = (void*)rpc_create;
		msg.data_size = sizeof(*rpc_create);
		break;
	}

	/* are we ok so far ? */
	if (!NT_STATUS_IS_OK(c->status)) {
		c->state = COMPOSITE_STATE_ERROR;
	}

	/* call monitor function provided the pointer has been passed */
	if (s->monitor_fn) {
		s->monitor_fn(&msg);
	}

	/* are we done yet ? */
	if (c->state >= COMPOSITE_STATE_DONE &&
	    c->async.fn) {
		c->async.fn(c);
	}
}


/**
 * Sends asynchronous useradd request
 *
 * @param p dce/rpc call pipe 
 * @param io arguments and results of the call
 * @param monitor monitor function for providing information about the progress
 */

struct composite_context *libnet_rpc_useradd_send(struct dcerpc_pipe *p,
						  struct libnet_rpc_useradd *io,
						  void (*monitor)(struct monitor_msg*))
{
	struct composite_context *c;
	struct useradd_state *s;

	/* composite allocation and setup */
	c = talloc_zero(p, struct composite_context);
	if (c == NULL) return NULL;
	
	s = talloc_zero(c, struct useradd_state);
	if (composite_nomem(s, c)) return c;
	
	c->state        = COMPOSITE_STATE_IN_PROGRESS;
	c->private_data = s;
	c->event_ctx    = dcerpc_event_context(p);

	/* put passed arguments to the state structure */
	s->domain_handle = io->in.domain_handle;
	s->pipe          = p;
	s->monitor_fn    = monitor;
	
	/* preparing parameters to send rpc request */
	s->createuser.in.domain_handle         = &io->in.domain_handle;
	s->createuser.in.account_name          = talloc_zero(c, struct lsa_String);
	s->createuser.in.account_name->string  = talloc_strdup(c, io->in.username);
	s->createuser.out.user_handle          = &s->user_handle;
	s->createuser.out.rid                  = &s->user_rid;

	/* send the request */
	s->req = dcerpc_samr_CreateUser_send(p, c, &s->createuser);
	if (composite_nomem(s->req, c)) return c;

	/* callback handler for continuation */
	s->req->async.callback = useradd_handler;
	s->req->async.private  = c;
	s->stage = USERADD_CREATE;

	return c;
}


/**
 * Waits for and receives result of asynchronous useradd call
 * 
 * @param c composite context returned by asynchronous useradd call
 * @param mem_ctx memory context of the call
 * @param io pointer to results (and arguments) of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_useradd_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
				 struct libnet_rpc_useradd *io)
{
	NTSTATUS status;
	struct useradd_state *s;
	
	status = composite_wait(c);
	
	if (NT_STATUS_IS_OK(status) && io) {
		/* get and return result of the call */
		s = talloc_get_type(c->private_data, struct useradd_state);
		io->out.user_handle = s->user_handle;
	}

	talloc_free(c);
	return status;
}


/**
 * Synchronous version of useradd call
 *
 * @param pipe dce/rpc call pipe
 * @param mem_ctx memory context for the call
 * @param io arguments and results of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_useradd(struct dcerpc_pipe *p,
			    TALLOC_CTX *mem_ctx,
			    struct libnet_rpc_useradd *io)
{
	struct composite_context *c = libnet_rpc_useradd_send(p, io, NULL);
	return libnet_rpc_useradd_recv(c, mem_ctx, io);
}



/*
 * Composite USER DELETE functionality
 */

static void userdel_handler(struct rpc_request*);

enum userdel_stage { USERDEL_LOOKUP, USERDEL_OPEN, USERDEL_DELETE };

struct userdel_state {
	enum userdel_stage        stage;
	struct dcerpc_pipe        *pipe;
	struct rpc_request        *req;
	struct policy_handle      domain_handle;
	struct policy_handle      user_handle;
	struct samr_LookupNames   lookupname;
	struct samr_OpenUser      openuser;
	struct samr_DeleteUser    deleteuser;

	/* information about the progress */
	void (*monitor_fn)(struct monitor_msg *);
};


/**
 * Stage 1: Lookup the user name and resolve it to rid
 */
static NTSTATUS userdel_lookup(struct composite_context *c,
			       struct userdel_state *s)
{
	/* receive samr_LookupNames result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	/* what to do when there's no user account to delete
	   and what if there's more than one rid resolved */
	if (!s->lookupname.out.rids.count) {
		c->status = NT_STATUS_NO_SUCH_USER;
		composite_error(c, c->status);

	} else if (!s->lookupname.out.rids.count > 1) {
		c->status = NT_STATUS_INVALID_ACCOUNT_NAME;
		composite_error(c, c->status);
	}

	/* prepare the next rpc call arguments */
	s->openuser.in.domain_handle = &s->domain_handle;
	s->openuser.in.rid           = s->lookupname.out.rids.ids[0];
	s->openuser.in.access_mask   = SEC_FLAG_MAXIMUM_ALLOWED;
	s->openuser.out.user_handle  = &s->user_handle;

	/* send rpc request */
	s->req = dcerpc_samr_OpenUser_send(s->pipe, c, &s->openuser);
	if (s->req == NULL) return NT_STATUS_NO_MEMORY;

	/* callback handler setup */
	s->req->async.callback = userdel_handler;
	s->req->async.private  = c;
	s->stage = USERDEL_OPEN;
	
	return NT_STATUS_OK;
}


/**
 * Stage 2: Open user account.
 */
static NTSTATUS userdel_open(struct composite_context *c,
			     struct userdel_state *s)
{
	/* receive samr_OpenUser result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	/* prepare the final rpc call arguments */
	s->deleteuser.in.user_handle   = &s->user_handle;
	s->deleteuser.out.user_handle  = &s->user_handle;
	
	/* send rpc request */
	s->req = dcerpc_samr_DeleteUser_send(s->pipe, c, &s->deleteuser);
	if (s->req == NULL) return NT_STATUS_NO_MEMORY;

	/* callback handler setup */
	s->req->async.callback = userdel_handler;
	s->req->async.private  = c;
	s->stage = USERDEL_DELETE;
	
	return NT_STATUS_OK;
}


/**
 * Stage 3: Delete user account
 */
static NTSTATUS userdel_delete(struct composite_context *c,
			       struct userdel_state *s)
{
	/* receive samr_DeleteUser result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	c->state = COMPOSITE_STATE_DONE;

	return NT_STATUS_OK;
}


/**
 * Event handler for asynchronous request. Handles transition through
 * intermediate stages of the call.
 *
 * @param req rpc call context
 */
static void userdel_handler(struct rpc_request *req)
{
	struct composite_context *c;
	struct userdel_state *s;
	struct monitor_msg msg;
	struct msg_rpc_lookup_name *msg_lookup;
	struct msg_rpc_open_user *msg_open;

	c = talloc_get_type(req->async.private, struct composite_context);
	s = talloc_get_type(c->private_data, struct userdel_state);
	
	switch (s->stage) {
	case USERDEL_LOOKUP:
		c->status = userdel_lookup(c, s);

		/* monitor message */
		msg.type = rpc_lookup_name;
		msg_lookup = talloc(s, struct msg_rpc_lookup_name);

		msg_lookup->rid   = s->lookupname.out.rids.ids;
		msg_lookup->count = s->lookupname.out.rids.count;
		msg.data = (void*)msg_lookup;
		msg.data_size = sizeof(*msg_lookup);
		break;

	case USERDEL_OPEN:
		c->status = userdel_open(c, s);

		/* monitor message */
		msg.type = rpc_open_user;
		msg_open = talloc(s, struct msg_rpc_open_user);

		msg_open->rid         = s->openuser.in.rid;
		msg_open->access_mask = s->openuser.in.rid;
		msg.data = (void*)msg_open;
		msg.data_size = sizeof(*msg_open);
		break;

	case USERDEL_DELETE:
		c->status = userdel_delete(c, s);
		
		/* monitor message */
		msg.type = rpc_delete_user;
		msg.data = NULL;
		msg.data_size = 0;
		break;
	}

	/* are we ok, so far ? */
	if (!NT_STATUS_IS_OK(c->status)) {
		c->state = COMPOSITE_STATE_ERROR;
	}

	/* call monitor function provided the pointer has been passed */
	if (s->monitor_fn) {
		s->monitor_fn(&msg);
	}

	/* are we done yet */
	if (c->state >= COMPOSITE_STATE_DONE &&
	    c->async.fn) {
		c->async.fn(c);
	}
}


/**
 * Sends asynchronous userdel request
 *
 * @param p dce/rpc call pipe
 * @param io arguments and results of the call
 * @param monitor monitor function for providing information about the progress
 */

struct composite_context *libnet_rpc_userdel_send(struct dcerpc_pipe *p,
						  struct libnet_rpc_userdel *io,
						  void (*monitor)(struct monitor_msg*))
{
	struct composite_context *c;
	struct userdel_state *s;

	/* composite context allocation and setup */
	c = talloc_zero(p, struct composite_context);
	if (c == NULL) return NULL;

	s = talloc_zero(c, struct userdel_state);
	if (composite_nomem(s, c)) return c;

	c->state         = COMPOSITE_STATE_IN_PROGRESS;
	c->private_data  = s;
	c->event_ctx     = dcerpc_event_context(p);

	/* store function parameters in the state structure */
	s->pipe          = p;
	s->domain_handle = io->in.domain_handle;
	s->monitor_fn    = monitor;
	
	/* preparing parameters to send rpc request */
	s->lookupname.in.domain_handle = &io->in.domain_handle;
	s->lookupname.in.num_names     = 1;
	s->lookupname.in.names         = talloc_zero(s, struct lsa_String);
	s->lookupname.in.names->string = io->in.username;

	/* send the request */
	s->req = dcerpc_samr_LookupNames_send(p, c, &s->lookupname);

	/* callback handler setup */
	s->req->async.callback = userdel_handler;
	s->req->async.private  = c;
	s->stage = USERDEL_LOOKUP;

	return c;
}


/**
 * Waits for and receives results of asynchronous userdel call
 *
 * @param c composite context returned by asynchronous userdel call
 * @param mem_ctx memory context of the call
 * @param io pointer to results (and arguments) of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_userdel_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
				 struct libnet_rpc_userdel *io)
{
	NTSTATUS status;
	struct userdel_state *s;
	
	status = composite_wait(c);

	if (NT_STATUS_IS_OK(status) && io) {
		s  = talloc_get_type(c->private_data, struct userdel_state);
		io->out.user_handle = s->user_handle;
	}

	talloc_free(c);
	return status;
}


/**
 * Synchronous version of userdel call
 *
 * @param pipe dce/rpc call pipe
 * @param mem_ctx memory context for the call
 * @param io arguments and results of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_userdel(struct dcerpc_pipe *p,
			    TALLOC_CTX *mem_ctx,
			    struct libnet_rpc_userdel *io)
{
	struct composite_context *c = libnet_rpc_userdel_send(p, io, NULL);
	return libnet_rpc_userdel_recv(c, mem_ctx, io);
}


/*
 * USER MODIFY functionality
 */

static void usermod_handler(struct rpc_request*);

enum usermod_stage { USERMOD_LOOKUP, USERMOD_OPEN, USERMOD_QUERY, USERMOD_MODIFY };

struct usermod_state {
	enum usermod_stage         stage;
	struct dcerpc_pipe         *pipe;
	struct rpc_request         *req;
	struct policy_handle       domain_handle;
	struct policy_handle       user_handle;
	struct usermod_change      change;
	union  samr_UserInfo       info;
	struct samr_LookupNames    lookupname;
	struct samr_OpenUser       openuser;
	struct samr_SetUserInfo    setuser;
	struct samr_QueryUserInfo  queryuser;

	/* information about the progress */
	void (*monitor_fn)(struct monitor_msg *);
};


/**
 * Step 1: Lookup user name
 */
static NTSTATUS usermod_lookup(struct composite_context *c,
			       struct usermod_state *s)
{
	/* receive samr_LookupNames result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	/* what to do when there's no user account to delete
	   and what if there's more than one rid resolved */
	if (!s->lookupname.out.rids.count) {
		c->status = NT_STATUS_NO_SUCH_USER;
		c->state  = COMPOSITE_STATE_ERROR;
		return c->status;

	} else if (!s->lookupname.out.rids.count > 1) {
		c->status = NT_STATUS_INVALID_ACCOUNT_NAME;
		c->state  = COMPOSITE_STATE_ERROR;
		return c->status;
	}

	/* prepare the next rpc call */
	s->openuser.in.domain_handle = &s->domain_handle;
	s->openuser.in.rid           = s->lookupname.out.rids.ids[0];
	s->openuser.in.access_mask   = SEC_FLAG_MAXIMUM_ALLOWED;
	s->openuser.out.user_handle  = &s->user_handle;

	/* send the rpc request */
	s->req = dcerpc_samr_OpenUser_send(s->pipe, c, &s->openuser);

	/* callback handler setup */
	s->req->async.callback = usermod_handler;
	s->req->async.private  = c;
	s->stage = USERMOD_OPEN;
	
	return NT_STATUS_OK;
}


/**
 * Choose a proper level of samr_UserInfo structure depending on required
 * change specified by means of flags field. Subsequent calls of this
 * function are made until there's no flags set meaning that all of the
 * changes have been made.
 */
static uint32_t usermod_setfields(struct usermod_state *s, uint16_t *level,
				  union samr_UserInfo *i)
{
	if (s->change.fields) {
		if (s->change.fields & USERMOD_FIELD_ACCOUNT_NAME) {
			*level = 7;
			i->info7.account_name.string = s->change.account_name;

			s->change.fields ^= USERMOD_FIELD_ACCOUNT_NAME;

		} else if (s->change.fields & USERMOD_FIELD_FULL_NAME) {
			*level = 8;
			i->info8.full_name.string = s->change.full_name;
			
			s->change.fields ^= USERMOD_FIELD_FULL_NAME;

		} else if (s->change.fields & USERMOD_FIELD_DESCRIPTION) {
			*level = 13;
			i->info13.description.string = s->change.description;
			
			s->change.fields ^= USERMOD_FIELD_DESCRIPTION;

		} else if (s->change.fields & USERMOD_FIELD_COMMENT) {
			*level = 2;

			if (s->stage == USERMOD_QUERY) {
				/* the user info is obtained, so now set the required field */
				i->info2.comment.string = s->change.comment;
				s->change.fields ^= USERMOD_FIELD_COMMENT;

			} else {
				/* we need to query the user info before setting one field in it */
				s->stage = USERMOD_QUERY;
				return s->change.fields;
			}

		} else if (s->change.fields & USERMOD_FIELD_ALLOW_PASS_CHG) {
			*level = 3;
			
			if (s->stage == USERMOD_QUERY) {
				i->info3.allow_password_change = timeval_to_nttime(s->change.allow_password_change);
				s->change.fields ^= USERMOD_FIELD_ALLOW_PASS_CHG;

			} else {
				s->stage = USERMOD_QUERY;
				return s->change.fields;
			}

		} else if (s->change.fields & USERMOD_FIELD_FORCE_PASS_CHG) {
			*level = 3;

			if (s->stage == USERMOD_QUERY) {
				i->info3.force_password_change = timeval_to_nttime(s->change.force_password_change);
				s->change.fields ^= USERMOD_FIELD_FORCE_PASS_CHG;

			} else {
				s->stage = USERMOD_QUERY;
				return s->change.fields;
			}

		} else if (s->change.fields & USERMOD_FIELD_LOGON_SCRIPT) {
			*level = 11;
			i->info11.logon_script.string = s->change.logon_script;
			
			s->change.fields ^= USERMOD_FIELD_LOGON_SCRIPT;

		} else if (s->change.fields & USERMOD_FIELD_PROFILE_PATH) {
			*level = 12;
			i->info12.profile_path.string = s->change.profile_path;

			s->change.fields ^= USERMOD_FIELD_PROFILE_PATH;

		} else if (s->change.fields & USERMOD_FIELD_ACCT_EXPIRY) {
			*level = 17;
			i->info17.acct_expiry = timeval_to_nttime(s->change.acct_expiry);

			s->change.fields ^= USERMOD_FIELD_ACCT_EXPIRY;

		} else if (s->change.fields & USERMOD_FIELD_ACCT_FLAGS) {
			*level = 16;
			i->info16.acct_flags = s->change.acct_flags;

			s->change.fields ^= USERMOD_FIELD_ACCT_FLAGS;
		}
	}

	/* We're going to be back here again soon unless all fields have been set */
	if (s->change.fields) {
		s->stage = USERMOD_OPEN;
	} else {
		s->stage = USERMOD_MODIFY;
	}

	return s->change.fields;
}


/**
 * Stage 2: Open user account
 */
static NTSTATUS usermod_open(struct composite_context *c,
			     struct usermod_state *s)
{
	union samr_UserInfo *i = &s->info;
	uint16_t level;

	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	/* prepare UserInfo level and data based on bitmask field */
	s->change.fields = usermod_setfields(s, &level, i);

	/* If some specific level is used to set user account data and the change
	   itself does not cover all fields then we need to query the user info
	   first, right before changing the data. Otherwise we could set required
	   fields and accidentally reset the others.
	*/
	if (s->stage == USERMOD_QUERY) {
		s->queryuser.in.user_handle = &s->user_handle;
		s->queryuser.in.level       = level;

		/* send query user info request to retrieve complete data of
		   a particular info level */
		s->req = dcerpc_samr_QueryUserInfo_send(s->pipe, c, &s->queryuser);

	} else {
		s->setuser.in.user_handle  = &s->user_handle;
		s->setuser.in.level        = level;
		s->setuser.in.info         = i;

		/* send set user info request after making required change */
		s->req = dcerpc_samr_SetUserInfo_send(s->pipe, c, &s->setuser);
	}

	/* callback handler setup */
	s->req->async.callback = usermod_handler;
	s->req->async.private  = c;

	return NT_STATUS_OK;
}


/**
 * Stage 2a (optional): Query the user information
 */
static NTSTATUS usermod_query(struct composite_context *c,
			      struct usermod_state *s)
{
	union samr_UserInfo *i = &s->info;
	uint16_t level;

	/* receive samr_QueryUserInfo result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	/* get returned user data and make a change (potentially one
	   of many) */
	s->info = *s->queryuser.out.info;

	s->change.fields = usermod_setfields(s, &level, i);

	/* prepare rpc call arguments */
	s->setuser.in.user_handle  = &s->user_handle;
	s->setuser.in.level        = level;
	s->setuser.in.info         = i;

	/* send the rpc request */
	s->req = dcerpc_samr_SetUserInfo_send(s->pipe, c, &s->setuser);

	/* callback handler setup */
	s->req->async.callback = usermod_handler;
	s->req->async.private  = c;

	return NT_STATUS_OK;
}


/**
 * Stage 3: Set new user account data
 */
static NTSTATUS usermod_modify(struct composite_context *c,
			       struct usermod_state *s)
{
	/* receive samr_SetUserInfo result */
	c->status = dcerpc_ndr_request_recv(s->req);
	NT_STATUS_NOT_OK_RETURN(c->status);

	c->state = COMPOSITE_STATE_DONE;

	return NT_STATUS_OK;
}


/**
 * Event handler for asynchronous request. Handles transition through
 * intermediate stages of the call.
 *
 * @param req rpc call context
 */

static void usermod_handler(struct rpc_request *req)
{
	struct composite_context *c;
	struct usermod_state *s;
	struct monitor_msg msg;
	struct msg_rpc_lookup_name *msg_lookup;
	struct msg_rpc_open_user *msg_open;

	c = talloc_get_type(req->async.private, struct composite_context);
	s = talloc_get_type(c->private_data, struct usermod_state);

	switch (s->stage) {
	case USERMOD_LOOKUP:
		c->status = usermod_lookup(c, s);
		
		/* monitor message */
		msg.type = rpc_lookup_name;
		msg_lookup = talloc(s, struct msg_rpc_lookup_name);

		msg_lookup->rid   = s->lookupname.out.rids.ids;
		msg_lookup->count = s->lookupname.out.rids.count;
		msg.data = (void*)msg_lookup;
		msg.data_size = sizeof(*msg_lookup);
		break;

	case USERMOD_OPEN:
		c->status = usermod_open(c, s);

		/* monitor message */
		msg.type = rpc_open_user;
		msg_open = talloc(s, struct msg_rpc_open_user);

		msg_open->rid         = s->openuser.in.rid;
		msg_open->access_mask = s->openuser.in.rid;
		msg.data = (void*)msg_open;
		msg.data_size = sizeof(*msg_open);
		break;

	case USERMOD_QUERY:
		c->status = usermod_query(c, s);

		/* monitor message */
		msg.type = rpc_query_user;
		msg.data = NULL;
		msg.data_size = 0;
		break;

	case USERMOD_MODIFY:
		c->status = usermod_modify(c, s);

		/* monitor message */
		msg.type = rpc_set_user;
		msg.data = NULL;
		msg.data_size = 0;
		break;
	}

	/* are we ok, so far ? */
	if (!NT_STATUS_IS_OK(c->status)) {
		c->state = COMPOSITE_STATE_ERROR;
	}

	/* call monitor function provided the pointer has been passed */
	if (s->monitor_fn) {
		s->monitor_fn(&msg);
	}

	/* are we done yet ? */
	if (c->state >= COMPOSITE_STATE_DONE &&
	    c->async.fn) {
		c->async.fn(c);
	}
}


/**
 * Sends asynchronous usermod request
 *
 * @param p dce/rpc call pipe
 * @param io arguments and results of the call
 * @param monitor monitor function for providing information about the progress
 */

struct composite_context *libnet_rpc_usermod_send(struct dcerpc_pipe *p,
						  struct libnet_rpc_usermod *io,
						  void (*monitor)(struct monitor_msg*))
{
	struct composite_context *c;
	struct usermod_state *s;

	/* composite context allocation and setup */
	c = talloc_zero(p, struct composite_context);
	if (c == NULL) return NULL;

	s = talloc_zero(c, struct usermod_state);
	if (composite_nomem(s, c)) return c;

	c->state        = COMPOSITE_STATE_IN_PROGRESS;
	c->private_data = s;
	c->event_ctx    = dcerpc_event_context(p);

	/* store parameters in the call structure */
	s->pipe          = p;
	s->domain_handle = io->in.domain_handle;
	s->change        = io->in.change;
	s->monitor_fn    = monitor;
	
	/* prepare rpc call arguments */
	s->lookupname.in.domain_handle = &io->in.domain_handle;
	s->lookupname.in.num_names     = 1;
	s->lookupname.in.names         = talloc_zero(s, struct lsa_String);
	s->lookupname.in.names->string = io->in.username;

	/* send the rpc request */
	s->req = dcerpc_samr_LookupNames_send(p, c, &s->lookupname);
	
	/* callback handler setup */
	s->req->async.callback = usermod_handler;
	s->req->async.private  = c;
	s->stage = USERMOD_LOOKUP;

	return c;
}


/**
 * Waits for and receives results of asynchronous usermod call
 *
 * @param c composite context returned by asynchronous usermod call
 * @param mem_ctx memory context of the call
 * @param io pointer to results (and arguments) of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_usermod_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
				 struct libnet_rpc_usermod *io)
{
	NTSTATUS status;
	
	status = composite_wait(c);

	talloc_free(c);
	return status;
}


/**
 * Synchronous version of usermod call
 *
 * @param pipe dce/rpc call pipe
 * @param mem_ctx memory context for the call
 * @param io arguments and results of the call
 * @return nt status code of execution
 */

NTSTATUS libnet_rpc_usermod(struct dcerpc_pipe *p,
			    TALLOC_CTX *mem_ctx,
			    struct libnet_rpc_usermod *io)
{
	struct composite_context *c = libnet_rpc_usermod_send(p, io, NULL);
	return libnet_rpc_usermod_recv(c, mem_ctx, io);
}