/* assuan-pipe-server.c - Assuan server working over a pipe

 * Copyright (C) 2001, 2002, 2009 Free Software Foundation, Inc.

 *

 * This file is part of Assuan.

 *

 * Assuan is free software; you can redistribute it and/or modify it

 * under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation; either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * Assuan 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this program; if not, see <http://www.gnu.org/licenses/>.

 * SPDX-License-Identifier: LGPL-2.1+

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <stdlib.h>

#include <stdio.h>

#ifdef HAVE_SYS_TYPES_H

# include <sys/types.h>

#endif

#ifdef HAVE_SYS_STAT_H

# include <sys/stat.h>

#endif

#ifdef HAVE_UNISTD_H

# include <unistd.h>

#endif

#ifdef HAVE_W32_SYSTEM

# ifdef HAVE_WINSOCK2_H

#  include <winsock2.h>

# endif

# include <windows.h>

#ifdef HAVE_FCNTL_H

# include <fcntl.h>

#endif

#endif

#include "assuan-defs.h"

#include "debug.h"

/* Returns true if atoi(S) denotes a valid socket. */

#ifndef HAVE_W32_SYSTEM

static int

is_valid_socket (const char *s)

{

  struct stat buf;

  if ( fstat (atoi (s), &buf ) )

    return 0;

  return S_ISSOCK (buf.st_mode);

}

#endif /*!HAVE_W32_SYSTEM*/

/* This actually is a int file descriptor (and not assuan_fd_t) as

   _get_osfhandle is called on W32 systems.  */

gpg_error_t

assuan_init_pipe_server (assuan_context_t ctx, assuan_fd_t filedes[2])

{

  const char *s;

  unsigned long ul;

  gpg_error_t rc;

  assuan_fd_t infd = ASSUAN_INVALID_FD;

  assuan_fd_t outfd = ASSUAN_INVALID_FD;

  int is_usd = 0;

  TRACE_BEG (ctx, ASSUAN_LOG_CTX, "assuan_init_pipe_server", ctx);

  if (filedes)

    {

      TRACE_LOG2 ("fd[0]=0x%x, fd[1]=0x%x", filedes[0], filedes[1]);

    }

  rc = _assuan_register_std_commands (ctx);

  if (rc)

    return TRACE_ERR (rc);

#ifdef HAVE_W32_SYSTEM

  if (filedes)

    {

      infd  = filedes[0];

      outfd = filedes[1];

    }

  else

    {

      infd = assuan_fd_from_posix_fd (0);

      outfd = assuan_fd_from_posix_fd (1);

    }

#else

  s = getenv ("_assuan_connection_fd");

  if (s && *s && is_valid_socket (s))

    {

      /* Well, we are called with an bi-directional file descriptor.

   Prepare for using sendmsg/recvmsg.  In this case we ignore

   the passed file descriptors. */

      infd = atoi (s);

      outfd = atoi (s);

      is_usd = 1;

    }

  else if (filedes && filedes[0] != ASSUAN_INVALID_FD

     && filedes[1] != ASSUAN_INVALID_FD )

    {

      /* Standard pipe server. */

      infd = filedes[0];

      outfd = filedes[1];

    }

  else

    {

      rc = _assuan_error (ctx, GPG_ERR_ASS_SERVER_START);

      return TRACE_ERR (rc);

    }

#endif

  ctx->flags.is_server = 1;

  ctx->engine.release = _assuan_server_release;

  ctx->engine.readfnc = _assuan_simple_read;

  ctx->engine.writefnc = _assuan_simple_write;

  ctx->engine.sendfd = NULL;

#ifdef HAVE_W32_SYSTEM

  ctx->engine.receivefd = w32_fdpass_recv;

#else

  ctx->engine.receivefd = NULL;

#endif

  ctx->max_accepts = 1;

  s = getenv ("_assuan_pipe_connect_pid");

  if (s && (ul=strtoul (s, NULL, 10)) && ul)

    ctx->pid = (pid_t)ul;

  else

    ctx->pid = (pid_t)-1;

  ctx->accept_handler = NULL;

  ctx->finish_handler = _assuan_server_finish;

  ctx->inbound.fd = infd;

  ctx->outbound.fd = outfd;

  if (is_usd)

    _assuan_init_uds_io (ctx);

  return TRACE_SUC();

}