/*
 *  Unix SMB/CIFS implementation.
 *  RPC client transport over named pipes
 *  Copyright (C) Volker Lendecke 2009
 *
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include "includes.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_RPC_CLI

struct rpc_transport_np_state {
	struct cli_state *cli;
	const char *pipe_name;
	uint16_t fnum;
};

static int rpc_transport_np_state_destructor(struct rpc_transport_np_state *s)
{
	bool ret;
	ret = cli_close(s->cli, s->fnum);
	if (!ret) {
		DEBUG(1, ("rpc_transport_np_state_destructor: cli_close "
			  "failed on pipe %s. Error was %s\n", s->pipe_name,
			  cli_errstr(s->cli)));
	}
	DEBUG(10, ("rpc_pipe_destructor: closed %s\n", s->pipe_name));
	/*
	 * We can't do much on failure
	 */
	return 0;
}

struct rpc_np_write_state {
	size_t size;
	size_t written;
};

static void rpc_np_write_done(struct async_req *subreq);

static struct async_req *rpc_np_write_send(TALLOC_CTX *mem_ctx,
					   struct event_context *ev,
					   const uint8_t *data, size_t size,
					   void *priv)
{
	struct rpc_transport_np_state *np_transport = talloc_get_type_abort(
		priv, struct rpc_transport_np_state);
	struct async_req *result, *subreq;
	struct rpc_np_write_state *state;

	if (!async_req_setup(mem_ctx, &result, &state,
			     struct rpc_np_write_state)) {
		return NULL;
	}
	state->size = size;

	subreq = cli_write_andx_send(mem_ctx, ev, np_transport->cli,
				     np_transport->fnum,
				     8, /* 8 means message mode. */
				     data, 0, size);
	if (subreq == NULL) {
		goto fail;
	}
	subreq->async.fn = rpc_np_write_done;
	subreq->async.priv = result;
	return result;
 fail:
	TALLOC_FREE(result);
	return NULL;
}

static void rpc_np_write_done(struct async_req *subreq)
{
	struct async_req *req = talloc_get_type_abort(
		subreq->async.priv, struct async_req);
	struct rpc_np_write_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_write_state);
	NTSTATUS status;

	status = cli_write_andx_recv(subreq, &state->written);
	TALLOC_FREE(subreq);
	if (!NT_STATUS_IS_OK(status)) {
		async_req_error(req, status);
		return;
	}
	async_req_done(req);
}

static NTSTATUS rpc_np_write_recv(struct async_req *req, ssize_t *pwritten)
{
	struct rpc_np_write_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_write_state);
	NTSTATUS status;

	if (async_req_is_error(req, &status)) {
		return status;
	}
	*pwritten = state->written;
	return NT_STATUS_OK;
}

struct rpc_np_read_state {
	uint8_t *data;
	size_t size;
	ssize_t received;
};

static void rpc_np_read_done(struct async_req *subreq);

static struct async_req *rpc_np_read_send(TALLOC_CTX *mem_ctx,
					  struct event_context *ev,
					  uint8_t *data, size_t size,
					  void *priv)
{
	struct rpc_transport_np_state *np_transport = talloc_get_type_abort(
		priv, struct rpc_transport_np_state);
	struct async_req *result, *subreq;
	struct rpc_np_read_state *state;

	if (!async_req_setup(mem_ctx, &result, &state,
			     struct rpc_np_read_state)) {
		return NULL;
	}
	state->data = data;
	state->size = size;

	subreq = cli_read_andx_send(mem_ctx, ev, np_transport->cli,
				    np_transport->fnum, 0, size);
	if (subreq == NULL) {
		goto fail;
	}
	subreq->async.fn = rpc_np_read_done;
	subreq->async.priv = result;
	return result;
 fail:
	TALLOC_FREE(result);
	return NULL;
}

static void rpc_np_read_done(struct async_req *subreq)
{
	struct async_req *req = talloc_get_type_abort(
		subreq->async.priv, struct async_req);
	struct rpc_np_read_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_read_state);
	NTSTATUS status;
	uint8_t *rcvbuf;

	status = cli_read_andx_recv(subreq, &state->received, &rcvbuf);
	/*
	 * We can't TALLOC_FREE(subreq) as usual here, as rcvbuf still is a
	 * child of that.
	 */
	if (NT_STATUS_EQUAL(status, NT_STATUS_BUFFER_TOO_SMALL)) {
		status = NT_STATUS_OK;
	}
	if (!NT_STATUS_IS_OK(status)) {
		TALLOC_FREE(subreq);
		async_req_error(req, status);
		return;
	}

	if (state->received > state->size) {
		TALLOC_FREE(subreq);
		async_req_error(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
		return;
	}

	memcpy(state->data, rcvbuf, state->received);
	async_req_done(req);
}

static NTSTATUS rpc_np_read_recv(struct async_req *req, ssize_t *preceived)
{
	struct rpc_np_read_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_read_state);
	NTSTATUS status;

	if (async_req_is_error(req, &status)) {
		return status;
	}
	*preceived = state->received;
	return NT_STATUS_OK;
}

struct rpc_np_trans_state {
	uint16_t setup[2];
	uint8_t *rdata;
	uint32_t rdata_len;
};

static void rpc_np_trans_done(struct async_req *subreq);

static struct async_req *rpc_np_trans_send(TALLOC_CTX *mem_ctx,
					   struct event_context *ev,
					   uint8_t *data, size_t data_len,
					   uint32_t max_rdata_len,
					   void *priv)
{
	struct rpc_transport_np_state *np_transport = talloc_get_type_abort(
		priv, struct rpc_transport_np_state);
	struct async_req *result, *subreq;
	struct rpc_np_trans_state *state;

	if (!async_req_setup(mem_ctx, &result, &state,
			     struct rpc_np_trans_state)) {
		return NULL;
	}

	SSVAL(state->setup+0, 0, TRANSACT_DCERPCCMD);
	SSVAL(state->setup+1, 0, np_transport->fnum);

	subreq = cli_trans_send(
		state, ev, np_transport->cli, SMBtrans,
		"\\PIPE\\", 0, 0, 0, state->setup, 2, 0,
		NULL, 0, 0, data, data_len, max_rdata_len);
	if (subreq == NULL) {
		goto fail;
	}
	subreq->async.fn = rpc_np_trans_done;
	subreq->async.priv = result;
	return result;

 fail:
	TALLOC_FREE(result);
	return NULL;
}

static void rpc_np_trans_done(struct async_req *subreq)
{
	struct async_req *req = talloc_get_type_abort(
		subreq->async.priv, struct async_req);
	struct rpc_np_trans_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_trans_state);
	NTSTATUS status;

	status = cli_trans_recv(subreq, state, NULL, NULL, NULL, NULL,
				&state->rdata, &state->rdata_len);
	TALLOC_FREE(subreq);
	if (!NT_STATUS_IS_OK(status)) {
		async_req_error(req, status);
		return;
	}
	async_req_done(req);
}

static NTSTATUS rpc_np_trans_recv(struct async_req *req, TALLOC_CTX *mem_ctx,
				  uint8_t **prdata, uint32_t *prdata_len)
{
	struct rpc_np_trans_state *state = talloc_get_type_abort(
		req->private_data, struct rpc_np_trans_state);
	NTSTATUS status;

	if (async_req_is_error(req, &status)) {
		return status;
	}
	*prdata = talloc_move(mem_ctx, &state->rdata);
	*prdata_len = state->rdata_len;
	return NT_STATUS_OK;
}

NTSTATUS rpc_transport_np_init(TALLOC_CTX *mem_ctx, struct cli_state *cli,
			       const struct ndr_syntax_id *abstract_syntax,
			       struct rpc_cli_transport **presult)
{
	struct rpc_cli_transport *result;
	struct rpc_transport_np_state *state;
	int fnum;

	result = talloc(mem_ctx, struct rpc_cli_transport);
	if (result == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	state = talloc(result, struct rpc_transport_np_state);
	if (state == NULL) {
		TALLOC_FREE(result);
		return NT_STATUS_NO_MEMORY;
	}
	result->priv = state;

	state->cli = cli;
	state->pipe_name = cli_get_pipe_name_from_iface(
		state, abstract_syntax);

	fnum = cli_nt_create(cli, state->pipe_name, DESIRED_ACCESS_PIPE);
	if (fnum == -1) {
		DEBUG(3,("rpc_pipe_open_np: cli_nt_create failed on pipe %s "
			 "to machine %s.  Error was %s\n", state->pipe_name,
			 cli->desthost, cli_errstr(cli)));
		TALLOC_FREE(result);
		return cli_get_nt_error(cli);
	}
	state->fnum = fnum;
	talloc_set_destructor(state, rpc_transport_np_state_destructor);

	result->write_send = rpc_np_write_send;
	result->write_recv = rpc_np_write_recv;
	result->read_send = rpc_np_read_send;
	result->read_recv = rpc_np_read_recv;
	result->trans_send = rpc_np_trans_send;
	result->trans_recv = rpc_np_trans_recv;

	*presult = result;
	return NT_STATUS_OK;
}

struct cli_state *rpc_pipe_np_smb_conn(struct rpc_pipe_client *p)
{
	struct rpc_transport_np_state *state = talloc_get_type(
		p->transport->priv, struct rpc_transport_np_state);

	if (state == NULL) {
		return NULL;
	}
	return state->cli;
}