/* engine-spawn.c - Run an arbitrary program
* Copyright (C) 2014 g10 Code GmbH
*
* This file is part of GPGME.
*
* GPGME 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.
*
* GPGME 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 <https://gnu.org/licenses/>.
* SPDX-License-Identifier: LGPL-2.1-or-later
*/
#if HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_LOCALE_H
#include <locale.h>
#endif
#include "gpgme.h"
#include "util.h"
#include "ops.h"
#include "wait.h"
#include "context.h" /*temp hack until we have GpmeData methods to do I/O */
#include "priv-io.h"
#include "sema.h"
#include "debug.h"
#include "engine-backend.h"
/* This type is used to build a list of data sources/sinks. */
struct datalist_s
{
struct datalist_s *next;
gpgme_data_t data; /* The data object. */
int inbound; /* True if this is used for reading from the peer. */
int dup_to; /* The fd used by the peer. */
};
struct fd_data_map_s
{
gpgme_data_t data;
int inbound; /* True if this is used for reading from the peer. */
int dup_to; /* Dup the fd to that one. */
int fd; /* The fd to use. */
int peer_fd; /* The other side of the pipe. */
void *tag; /* Tag used by the I/O callback. */
};
struct engine_spawn
{
struct datalist_s *arglist;
struct datalist_s **argtail;
struct fd_data_map_s *fd_data_map;
struct gpgme_io_cbs io_cbs;
};
typedef struct engine_spawn *engine_spawn_t;
static void engspawn_io_event (void *engine,
gpgme_event_io_t type, void *type_data);
static gpgme_error_t engspawn_cancel (void *engine);
static void
close_notify_handler (int fd, void *opaque)
{
engine_spawn_t esp = opaque;
int i;
assert (fd != -1);
if (esp->fd_data_map)
{
for (i = 0; esp->fd_data_map[i].data; i++)
{
if (esp->fd_data_map[i].fd == fd)
{
if (esp->fd_data_map[i].tag)
(*esp->io_cbs.remove) (esp->fd_data_map[i].tag);
esp->fd_data_map[i].fd = -1;
break;
}
if (esp->fd_data_map[i].peer_fd == fd)
{
esp->fd_data_map[i].peer_fd = -1;
break;
}
}
}
}
static gpgme_error_t
add_data (engine_spawn_t esp, gpgme_data_t data, int dup_to, int inbound)
{
struct datalist_s *a;
assert (esp);
assert (data);
a = malloc (sizeof *a);
if (!a)
return gpg_error_from_syserror ();
a->next = NULL;
a->data = data;
a->inbound = inbound;
a->dup_to = dup_to;
*esp->argtail = a;
esp->argtail = &a->next;
return 0;
}
static void
free_fd_data_map (struct fd_data_map_s *fd_data_map)
{
int i;
if (!fd_data_map)
return;
for (i = 0; fd_data_map[i].data; i++)
{
if (fd_data_map[i].fd != -1)
_gpgme_io_close (fd_data_map[i].fd);
if (fd_data_map[i].peer_fd != -1)
_gpgme_io_close (fd_data_map[i].peer_fd);
/* Don't release data because this is only a reference. */
}
free (fd_data_map);
}
static gpgme_error_t
build_fd_data_map (engine_spawn_t esp)
{
struct datalist_s *a;
size_t datac;
int fds[2];
for (datac = 0, a = esp->arglist; a; a = a->next)
if (a->data)
datac++;
free_fd_data_map (esp->fd_data_map);
esp->fd_data_map = calloc (datac + 1, sizeof *esp->fd_data_map);
if (!esp->fd_data_map)
return gpg_error_from_syserror ();
for (datac = 0, a = esp->arglist; a; a = a->next)
{
assert (a->data);
if (_gpgme_io_pipe (fds, a->inbound ? 1 : 0) == -1)
{
free (esp->fd_data_map);
esp->fd_data_map = NULL;
return gpg_error_from_syserror ();
}
if (_gpgme_io_set_close_notify (fds[0], close_notify_handler, esp)
|| _gpgme_io_set_close_notify (fds[1], close_notify_handler, esp))
{
/* FIXME: Need error cleanup. */
return gpg_error (GPG_ERR_GENERAL);
}
esp->fd_data_map[datac].inbound = a->inbound;
if (a->inbound)
{
esp->fd_data_map[datac].fd = fds[0];
esp->fd_data_map[datac].peer_fd = fds[1];
}
else
{
esp->fd_data_map[datac].fd = fds[1];
esp->fd_data_map[datac].peer_fd = fds[0];
}
esp->fd_data_map[datac].data = a->data;
esp->fd_data_map[datac].dup_to = a->dup_to;
datac++;
}
return 0;
}
static gpgme_error_t
add_io_cb (engine_spawn_t esp, int fd, int dir, gpgme_io_cb_t handler,
void *data, void **tag)
{
gpgme_error_t err;
err = (*esp->io_cbs.add) (esp->io_cbs.add_priv, fd, dir, handler, data, tag);
if (err)
return err;
if (!dir) /* Fixme: Kludge around poll() problem. */
err = _gpgme_io_set_nonblocking (fd);
return err;
}
static gpgme_error_t
engspawn_start (engine_spawn_t esp, const char *file, const char *argv[],
unsigned int flags)
{
gpgme_error_t err;
int i, n;
int status;
struct spawn_fd_item_s *fd_list;
pid_t pid;
unsigned int spflags;
const char *save_argv0 = NULL;
if (!esp || !file || !argv || !argv[0])
return gpg_error (GPG_ERR_INV_VALUE);
spflags = 0;
if ((flags & GPGME_SPAWN_DETACHED))
spflags |= IOSPAWN_FLAG_DETACHED;
if ((flags & GPGME_SPAWN_ALLOW_SET_FG))
spflags |= IOSPAWN_FLAG_ALLOW_SET_FG;
if ((flags & GPGME_SPAWN_SHOW_WINDOW))
spflags |= IOSPAWN_FLAG_SHOW_WINDOW;
err = build_fd_data_map (esp);
if (err)
return err;
n = 0;
for (i = 0; esp->fd_data_map[i].data; i++)
n++;
fd_list = calloc (n+1, sizeof *fd_list);
if (!fd_list)
return gpg_error_from_syserror ();
/* Build the fd list for the child. */
n = 0;
for (i = 0; esp->fd_data_map[i].data; i++)
{
fd_list[n].fd = esp->fd_data_map[i].peer_fd;
fd_list[n].dup_to = esp->fd_data_map[i].dup_to;
n++;
}
fd_list[n].fd = -1;
fd_list[n].dup_to = -1;
if (argv[0] && !*argv[0])
{
save_argv0 = argv[0];
argv[0] = _gpgme_get_basename (file);
}
status = _gpgme_io_spawn (file, (char * const *)argv, spflags,
fd_list, NULL, NULL, &pid);
if (save_argv0)
argv[0] = save_argv0;
free (fd_list);
if (status == -1)
return gpg_error_from_syserror ();
for (i = 0; esp->fd_data_map[i].data; i++)
{
err = add_io_cb (esp, esp->fd_data_map[i].fd,
esp->fd_data_map[i].inbound,
esp->fd_data_map[i].inbound
? _gpgme_data_inbound_handler
: _gpgme_data_outbound_handler,
esp->fd_data_map[i].data, &esp->fd_data_map[i].tag);
if (err)
return err; /* FIXME: kill the child */
}
engspawn_io_event (esp, GPGME_EVENT_START, NULL);
return 0;
}
/*
Public functions
*/
static const char *
engspawn_get_file_name (void)
{
return "/nonexistent";
}
static char *
engspawn_get_version (const char *file_name)
{
(void)file_name;
return NULL;
}
static const char *
engspawn_get_req_version (void)
{
return NULL;
}
static gpgme_error_t
engspawn_new (void **engine, const char *file_name, const char *home_dir,
const char *version)
{
engine_spawn_t esp;
(void)file_name;
(void)home_dir;
(void)version;
esp = calloc (1, sizeof *esp);
if (!esp)
return gpg_error_from_syserror ();
esp->argtail = &esp->arglist;
*engine = esp;
return 0;
}
static void
engspawn_release (void *engine)
{
engine_spawn_t esp = engine;
if (!esp)
return;
engspawn_cancel (engine);
while (esp->arglist)
{
struct datalist_s *next = esp->arglist->next;
free (esp->arglist);
esp->arglist = next;
}
free (esp);
}
static void
engspawn_set_io_cbs (void *engine, gpgme_io_cbs_t io_cbs)
{
engine_spawn_t esp = engine;
esp->io_cbs = *io_cbs;
}
static void
engspawn_io_event (void *engine, gpgme_event_io_t type, void *type_data)
{
engine_spawn_t esp = engine;
TRACE (DEBUG_ENGINE, "gpgme:engspawn_io_event", esp,
"event %p, type %d, type_data %p",
esp->io_cbs.event, type, type_data);
if (esp->io_cbs.event)
(*esp->io_cbs.event) (esp->io_cbs.event_priv, type, type_data);
}
static gpgme_error_t
engspawn_cancel (void *engine)
{
engine_spawn_t esp = engine;
if (!esp)
return gpg_error (GPG_ERR_INV_VALUE);
if (esp->fd_data_map)
{
free_fd_data_map (esp->fd_data_map);
esp->fd_data_map = NULL;
}
return 0;
}
static gpgme_error_t
engspawn_op_spawn (void *engine,
const char *file, const char *argv[],
gpgme_data_t datain,
gpgme_data_t dataout, gpgme_data_t dataerr,
unsigned int flags)
{
engine_spawn_t esp = engine;
gpgme_error_t err = 0;
if (datain)
err = add_data (esp, datain, 0, 0);
if (!err && dataout)
err = add_data (esp, dataout, 1, 1);
if (!err && dataerr)
err = add_data (esp, dataerr, 2, 1);
if (!err)
err = engspawn_start (esp, file, argv, flags);
return err;
}
struct engine_ops _gpgme_engine_ops_spawn =
{
/* Static functions. */
engspawn_get_file_name,
NULL, /* get_home_dir */
engspawn_get_version,
engspawn_get_req_version,
engspawn_new,
/* Member functions. */
engspawn_release,
NULL, /* reset */
NULL, /* set_status_cb */
NULL, /* set_status_handler */
NULL, /* set_command_handler */
NULL, /* set_colon_line_handler */
NULL, /* set_locale */
NULL, /* set_protocol */
NULL, /* set_engine_flags */
NULL, /* decrypt */
NULL, /* delete */
NULL, /* edit */
NULL, /* encrypt */
NULL, /* encrypt_sign */
NULL, /* export */
NULL, /* export_ext */
NULL, /* genkey */
NULL, /* import */
NULL, /* keylist */
NULL, /* keylist_ext */
NULL, /* keylist_data */
NULL, /* keysign */
NULL, /* tofu_policy */
NULL, /* sign */
NULL, /* trustlist */
NULL, /* verify */
NULL, /* getauditlog */
NULL, /* opassuan_transact */
NULL, /* conf_load */
NULL, /* conf_save */
NULL, /* conf_dir */
NULL, /* query_swdb */
engspawn_set_io_cbs,
engspawn_io_event, /* io_event */
engspawn_cancel, /* cancel */
NULL, /* cancel_op */
NULL, /* passwd */
NULL, /* set_pinentry_mode */
engspawn_op_spawn /* opspawn */
};