/* export.c - Export a key.
 * Copyright (C) 2000 Werner Koch (dd9jn)
 * Copyright (C) 2001-2004, 2010, 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 <stdlib.h>
#include <string.h>

#include "gpgme.h"
#include "util.h"
#include "debug.h"
#include "context.h"
#include "ops.h"


/* Local operation data.  */
typedef struct
{
  gpg_error_t err;  /* Error encountered during the export.  */
} *op_data_t;


static void
release_op_data (void *hook)
{
  op_data_t opd = (op_data_t) hook;

  (void)opd;  /* Nothing to release here.  */
}


/* Parse an error status line.  Return the error location and the
   error code.  The function may modify ARGS. */
static char *
parse_error (char *args, gpg_error_t *r_err)
{
  char *where = strchr (args, ' ');
  char *which;

  if (where)
    {
      *where = '\0';
      which = where + 1;

      where = strchr (which, ' ');
      if (where)
	*where = '\0';

      where = args;
    }
  else
    {
      *r_err = trace_gpg_error (GPG_ERR_INV_ENGINE);
      return NULL;
    }

  *r_err = atoi (which);

  return where;
}


static gpgme_error_t
export_status_handler (void *priv, gpgme_status_code_t code, char *args)
{
  gpgme_ctx_t ctx = (gpgme_ctx_t) priv;
  gpgme_error_t err;
  void *hook;
  op_data_t opd;
  const char *loc;

  err = _gpgme_passphrase_status_handler (priv, code, args);
  if (err)
    return err;

  err = _gpgme_op_data_lookup (ctx, OPDATA_EXPORT, &hook, -1, NULL);
  opd = hook;
  if (err)
    return err;

  switch (code)
    {
    case GPGME_STATUS_ERROR:
      loc = parse_error (args, &err);
      if (!loc)
        return err;
      else if (opd->err)
        ; /* We only want to report the first error.  */
      else if (!strcmp (loc, "keyserver_send")
               || !strcmp (loc, "export_keys.secret"))
        opd->err = err;
      break;

    default:
      break;
    }
  return 0;
}


static gpgme_error_t
check_mode (gpgme_export_mode_t mode, gpgme_protocol_t protocol,
            gpgme_data_t keydata)
{
  if ((mode & ~(GPGME_EXPORT_MODE_EXTERN
                |GPGME_EXPORT_MODE_MINIMAL
                |GPGME_EXPORT_MODE_SECRET
                |GPGME_EXPORT_MODE_SSH
                |GPGME_EXPORT_MODE_RAW
                |GPGME_EXPORT_MODE_PKCS12
                |GPGME_EXPORT_MODE_SECRET_SUBKEY)))
    return gpg_error (GPG_ERR_INV_VALUE); /* Invalid flags in MODE.  */

  if ((mode & GPGME_EXPORT_MODE_SSH))
    {
       if ((mode & (GPGME_EXPORT_MODE_EXTERN
                    |GPGME_EXPORT_MODE_MINIMAL
                    |GPGME_EXPORT_MODE_SECRET
                    |GPGME_EXPORT_MODE_RAW
                    |GPGME_EXPORT_MODE_PKCS12
                    |GPGME_EXPORT_MODE_SECRET_SUBKEY)))
          return gpg_error (GPG_ERR_INV_FLAG);  /* Combination not allowed. */
    }

  if ((mode & GPGME_EXPORT_MODE_SECRET))
    {
      if ((mode & GPGME_EXPORT_MODE_EXTERN))
        return gpg_error (GPG_ERR_INV_FLAG);  /* Combination not allowed. */
      if ((mode & GPGME_EXPORT_MODE_RAW)
          && (mode & GPGME_EXPORT_MODE_PKCS12))
        return gpg_error (GPG_ERR_INV_FLAG);  /* Combination not allowed. */

      if (protocol != GPGME_PROTOCOL_CMS
          && (mode & (GPGME_EXPORT_MODE_RAW|GPGME_EXPORT_MODE_PKCS12)))
        return gpg_error (GPG_ERR_INV_FLAG);  /* Only supported for X.509.  */
    }

  if ((mode & GPGME_EXPORT_MODE_SECRET_SUBKEY))
    {
      if ((mode & GPGME_EXPORT_MODE_EXTERN))
        return gpg_error (GPG_ERR_INV_FLAG);  /* Combination not allowed. */
    }

  if ((mode & GPGME_EXPORT_MODE_EXTERN))
    {
      if (keydata)
        return gpg_error (GPG_ERR_INV_VALUE);
    }
  else
    {
      if (!keydata)
        return gpg_error (GPG_ERR_INV_VALUE);
    }

  return 0;
}


static gpgme_error_t
export_start (gpgme_ctx_t ctx, int synchronous, const char *pattern,
	      gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;
  void *hook;
  op_data_t opd;

  err = check_mode (mode, ctx->protocol, keydata);
  if (err)
    return err;

  err = _gpgme_op_reset (ctx, synchronous);
  if (err)
    return err;

  err = _gpgme_op_data_lookup (ctx, OPDATA_EXPORT, &hook,
			       sizeof (*opd), release_op_data);
  opd = hook;
  if (err)
    return err;

  if (ctx->passphrase_cb)
    {
      err = _gpgme_engine_set_command_handler
	(ctx->engine, _gpgme_passphrase_command_handler, ctx);
      if (err)
	return err;
    }

  _gpgme_engine_set_status_handler (ctx->engine, export_status_handler, ctx);

  return _gpgme_engine_op_export (ctx->engine, pattern, mode, keydata,
				  ctx->use_armor);
}


/* Export the keys listed in PATTERN into KEYDATA.  */
gpgme_error_t
gpgme_op_export_start (gpgme_ctx_t ctx, const char *pattern,
		       gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export_start", ctx,
	      "pattern=%s, mode=0x%x, keydata=%p", pattern, mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  err = export_start (ctx, 0, pattern, mode, keydata);
  return TRACE_ERR (err);
}


/* Export the keys listed in PATTERN into KEYDATA.  */
gpgme_error_t
gpgme_op_export (gpgme_ctx_t ctx, const char *pattern,
		 gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export", ctx,
	      "pattern=%s, mode=0x%x, keydata=%p", pattern, mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  err = export_start (ctx, 1, pattern, mode, keydata);
  if (!err)
    err = _gpgme_wait_one (ctx);
  return err;
}


static gpgme_error_t
export_ext_start (gpgme_ctx_t ctx, int synchronous, const char *pattern[],
		  gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;
  void *hook;
  op_data_t opd;

  err = check_mode (mode, ctx->protocol, keydata);
  if (err)
    return err;

  err = _gpgme_op_reset (ctx, synchronous);
  if (err)
    return err;

  err = _gpgme_op_data_lookup (ctx, OPDATA_EXPORT, &hook,
			       sizeof (*opd), release_op_data);
  opd = hook;
  if (err)
    return err;

  if (ctx->passphrase_cb)
    {
      err = _gpgme_engine_set_command_handler
	(ctx->engine, _gpgme_passphrase_command_handler, ctx);
      if (err)
	return err;
    }

  _gpgme_engine_set_status_handler (ctx->engine, export_status_handler, ctx);

  return _gpgme_engine_op_export_ext (ctx->engine, pattern, mode, keydata,
				      ctx->use_armor);
}


/* Export the keys listed in PATTERN into KEYDATA.  */
gpgme_error_t
gpgme_op_export_ext_start (gpgme_ctx_t ctx, const char *pattern[],
			   gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export_ext_start", ctx,
	      "mode=0x%x, keydata=%p", mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  if (_gpgme_debug_trace () && pattern)
    {
      int i = 0;

      while (pattern[i])
	{
	  TRACE_LOG  ("pattern[%i] = %s", i, pattern[i]);
	  i++;
	}
    }

  err = export_ext_start (ctx, 0, pattern, mode, keydata);
  return TRACE_ERR (err);
}


/* Export the keys listed in PATTERN into KEYDATA.  */
gpgme_error_t
gpgme_op_export_ext (gpgme_ctx_t ctx, const char *pattern[],
		     gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export_ext_start", ctx,
	      "mode=0x%x, keydata=%p", mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  if (_gpgme_debug_trace () && pattern)
    {
      int i = 0;

      while (pattern[i])
	{
	  TRACE_LOG  ("pattern[%i] = %s", i, pattern[i]);
	  i++;
	}
    }

  err = export_ext_start (ctx, 1, pattern, mode, keydata);
  if (!err)
    {
      err = _gpgme_wait_one (ctx);
      if (!err)
        {
          /* For this synchronous operation we check for operational
             errors and return them.  For asynchronous operations
             there is currently no way to do this - we need to add a
             gpgme_op_export_result function to fix that.  */
          void *hook;
          op_data_t opd;

          err = _gpgme_op_data_lookup (ctx, OPDATA_EXPORT, &hook, -1, NULL);
          opd = hook;
          if (!err)
            err = opd->err;
        }
    }

  return TRACE_ERR (err);
}





static gpgme_error_t
export_keys_start (gpgme_ctx_t ctx, int synchronous, gpgme_key_t keys[],
                   gpgme_export_mode_t mode, gpgme_data_t keydata)
{
  gpgme_error_t err;
  int nkeys, idx;
  char **pattern;

  if (!keys)
    return gpg_error (GPG_ERR_INV_VALUE);

  if ((mode & GPGME_EXPORT_MODE_SECRET_SUBKEY))
    {
      return gpg_error (GPG_ERR_INV_FLAG);
    }

  /* Create a list of pattern from the keys.  */
  for (idx=nkeys=0; keys[idx]; idx++)
    if (keys[idx]->protocol == ctx->protocol)
      nkeys++;
  if (!nkeys)
    return gpg_error (GPG_ERR_NO_DATA);

  pattern = calloc (nkeys+1, sizeof *pattern);
  if (!pattern)
    return gpg_error_from_syserror ();

  for (idx=nkeys=0; keys[idx]; idx++)
    if (keys[idx]->protocol == ctx->protocol
        && keys[idx]->subkeys
        && keys[idx]->subkeys->fpr
        && *keys[idx]->subkeys->fpr)
      {
        pattern[nkeys] = strdup (keys[idx]->subkeys->fpr);
        if (!pattern[nkeys])
          {
            err = gpg_error_from_syserror ();
            goto leave;
          }
        nkeys++;
      }


  /* Pass on to the regular function.  */
  err = export_ext_start (ctx, synchronous, (const char**)pattern,
                          mode, keydata);

 leave:
  for (idx=0; pattern[idx]; idx++)
    free (pattern[idx]);
  free (pattern);

  return err;
}


/* Export the keys from the array KEYS into KEYDATA.  Only keys of the
   current protocol are exported and only those which have a
   fingerprint set; that is keys received with some external search
   methods are silently skipped.  */
gpgme_error_t
gpgme_op_export_keys_start (gpgme_ctx_t ctx,
                            gpgme_key_t keys[],
                            gpgme_export_mode_t mode,
                            gpgme_data_t keydata)
{
  gpg_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export_keys_start", ctx,
	      "mode=0x%x, keydata=%p", mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  if (_gpgme_debug_trace () && keys)
    {
      int i = 0;

      while (keys[i])
	{
	  TRACE_LOG  ("keys[%i] = %p (%s)", i, keys[i],
		      (keys[i]->subkeys && keys[i]->subkeys->fpr) ?
		      keys[i]->subkeys->fpr : "invalid");
	  i++;
	}
    }

  err = export_keys_start (ctx, 0, keys, mode, keydata);
  return TRACE_ERR (err);
}

gpgme_error_t
gpgme_op_export_keys (gpgme_ctx_t ctx,
                      gpgme_key_t keys[],
                      gpgme_export_mode_t mode,
                      gpgme_data_t keydata)
{
  gpgme_error_t err;

  TRACE_BEG  (DEBUG_CTX, "gpgme_op_export_keys", ctx,
	      "mode=0x%x, keydata=%p", mode, keydata);

  if (!ctx)
    return TRACE_ERR (gpg_error (GPG_ERR_INV_VALUE));

  if (_gpgme_debug_trace () && keys)
    {
      int i = 0;

      while (keys[i])
	{
	  TRACE_LOG  ("keys[%i] = %p (%s)", i, keys[i],
		      (keys[i]->subkeys && keys[i]->subkeys->fpr) ?
		      keys[i]->subkeys->fpr : "invalid");
	  i++;
	}
    }

  err = export_keys_start (ctx, 1, keys, mode, keydata);
  if (!err)
    {
      err = _gpgme_wait_one (ctx);
      if (!err)
        {
          /* For this synchronous operation we check for operational
             errors and return them.  For asynchronous operations
             there is currently no way to do this - we need to add a
             gpgme_op_export_result function to fix that.  */
          void *hook;
          op_data_t opd;

          err = _gpgme_op_data_lookup (ctx, OPDATA_EXPORT, &hook, -1, NULL);
          opd = hook;
          if (!err)
            err = opd->err;
        }
    }

  return TRACE_ERR (err);
}
