/* run-decrypt.c  - Helper to perform a verify operation

 * Copyright (C) 2009 g10 Code GmbH

 *               2016 by Bundesamt für Sicherheit in der Informationstechnik

 *               Software engineering by Intevation 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

 */

/* We need to include config.h so that we know whether we are building

   with large file system (LFS) support. */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#include <gpgme.h>

#define PGM "run-decrypt"

#include "run-support.h"

static int verbose;

static gpg_error_t

status_cb (void *opaque, const char *keyword, const char *value)

{

  (void)opaque;

  fprintf (stderr, "status_cb: %s %s\n", keyword, value);

  return 0;

}

static void

print_result (gpgme_decrypt_result_t result)

{

  gpgme_recipient_t recp;

  int count = 0;

  printf ("Original file name .: %s\n", nonnull(result->file_name));

  printf ("Wrong key usage ....: %s\n", result->wrong_key_usage? "yes":"no");

  printf ("Legacy w/o MDC ... .: %s\n", result->legacy_cipher_nomdc?"yes":"no");

  printf ("Compliance de-vs ...: %s\n", result->is_de_vs? "yes":"no");

  printf ("MIME flag ..........: %s\n", result->is_mime? "yes":"no");

  printf ("Unsupported algo ...: %s\n", nonnull(result->unsupported_algorithm));

  printf ("Session key ........: %s\n", nonnull (result->session_key));

  printf ("Symmetric algorithm : %s\n", result->symkey_algo);

  for (recp = result->recipients; recp && recp->next; recp = recp->next)

    {

      printf ("Recipient ...: %d\n", count++);

      printf ("  status ....: %s\n", gpgme_strerror (recp->status));

      printf ("  keyid .....: %s\n", nonnull (recp->keyid));

      printf ("  algo ......: %s\n",

              gpgme_pubkey_algo_name (recp->pubkey_algo));

    }

}

static int

show_usage (int ex)

{

  fputs ("usage: " PGM " [options] FILE\n\n"

         "Options:\n"

         "  --verbose        run in verbose mode\n"

         "  --status         print status lines from the backend\n"

         "  --openpgp        use the OpenPGP protocol (default)\n"

         "  --cms            use the CMS protocol\n"

         "  --export-session-key            show the session key\n"

         "  --override-session-key STRING   use STRING as session key\n"

         "  --request-origin STRING         use STRING as request origin\n"

         "  --no-symkey-cache               disable the use of that cache\n"

         "  --ignore-mdc-error              allow decryption of legacy data\n"

         "  --unwrap         remove only the encryption layer\n"

         "  --diagnostics    print diagnostics\n"

         , stderr);

  exit (ex);

}

int

main (int argc, char **argv)

{

  int last_argc = -1;

  gpgme_error_t err;

  gpgme_ctx_t ctx;

  gpgme_protocol_t protocol = GPGME_PROTOCOL_OpenPGP;

  gpgme_decrypt_flags_t flags = 0;

  FILE *fp_in = NULL;

  gpgme_data_t in = NULL;

  gpgme_data_t out = NULL;

  gpgme_decrypt_result_t result;

  int print_status = 0;

  int export_session_key = 0;

  const char *override_session_key = NULL;

  const char *request_origin = NULL;

  int no_symkey_cache = 0;

  int ignore_mdc_error = 0;

  int raw_output = 0;

  int diagnostics = 0;

  if (argc)

    { argc--; argv++; }

  while (argc && last_argc != argc )

    {

      last_argc = argc;

      if (!strcmp (*argv, "--"))

        {

          argc--; argv++;

          break;

        }

      else if (!strcmp (*argv, "--help"))

        show_usage (0);

      else if (!strcmp (*argv, "--verbose"))

        {

          verbose = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--status"))

        {

          print_status = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--openpgp"))

        {

          protocol = GPGME_PROTOCOL_OpenPGP;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--cms"))

        {

          protocol = GPGME_PROTOCOL_CMS;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--export-session-key"))

        {

          export_session_key = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--override-session-key"))

        {

          argc--; argv++;

          if (!argc)

            show_usage (1);

          override_session_key = *argv;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--request-origin"))

        {

          argc--; argv++;

          if (!argc)

            show_usage (1);

          request_origin = *argv;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--no-symkey-cache"))

        {

          no_symkey_cache = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--ignore-mdc-error"))

        {

          ignore_mdc_error = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--diagnostics"))

        {

          diagnostics = 1;

          argc--; argv++;

        }

      else if (!strcmp (*argv, "--unwrap"))

        {

          flags |= GPGME_DECRYPT_UNWRAP;

          raw_output = 1;

          argc--; argv++;

        }

      else if (!strncmp (*argv, "--", 2))

        show_usage (1);

    }

  if (argc < 1 || argc > 2)

    show_usage (1);

  fp_in = fopen (argv[0], "rb");

  if (!fp_in)

    {

      err = gpgme_error_from_syserror ();

      fprintf (stderr, PGM ": can't open `%s': %s\n",

               argv[0], gpgme_strerror (err));

      exit (1);

    }

  init_gpgme (protocol);

  err = gpgme_new (&ctx;;

  fail_if_err (err);

  gpgme_set_protocol (ctx, protocol);

  if (print_status)

    {

      gpgme_set_status_cb (ctx, status_cb, NULL);

      gpgme_set_ctx_flag (ctx, "full-status", "1");

    }

  if (export_session_key)

    {

      err = gpgme_set_ctx_flag (ctx, "export-session-key", "1");

      if (err)

        {

          fprintf (stderr, PGM ": error requesting exported session key: %s\n",

                   gpgme_strerror (err));

          exit (1);

        }

    }

  if (override_session_key)

    {

      err = gpgme_set_ctx_flag (ctx, "override-session-key",

                                override_session_key);

      if (err)

        {

          fprintf (stderr, PGM ": error setting overriding session key: %s\n",

                   gpgme_strerror (err));

          exit (1);

        }

    }

  if (request_origin)

    {

      err = gpgme_set_ctx_flag (ctx, "request-origin", request_origin);

      if (err)

        {

          fprintf (stderr, PGM ": error setting request_origin: %s\n",

                   gpgme_strerror (err));

          exit (1);

        }

    }

  if (no_symkey_cache)

    {

      err = gpgme_set_ctx_flag (ctx, "no-symkey-cache", "1");

      if (err)

        {

          fprintf (stderr, PGM ": error setting no-symkey-cache: %s\n",

                   gpgme_strerror (err));

          exit (1);

        }

    }

  if (ignore_mdc_error)

    {

      err = gpgme_set_ctx_flag (ctx, "ignore-mdc-error", "1");

      if (err)

        {

          fprintf (stderr, PGM ": error setting ignore-mdc-error: %s\n",

                   gpgme_strerror (err));

          exit (1);

        }

    }

  err = gpgme_data_new_from_stream (&in, fp_in);

  if (err)

    {

      fprintf (stderr, PGM ": error allocating data object: %s\n",

               gpgme_strerror (err));

      exit (1);

    }

  err = gpgme_data_new (&out;;

  if (err)

    {

      fprintf (stderr, PGM ": error allocating data object: %s\n",

               gpgme_strerror (err));

      exit (1);

    }

  err = gpgme_op_decrypt_ext (ctx, flags, in, out);

  result = gpgme_op_decrypt_result (ctx);

  if (diagnostics)

    {

      gpgme_data_t diag;

      gpgme_error_t diag_err;

      gpgme_data_new (&diag;;

      diag_err = gpgme_op_getauditlog (ctx, diag, GPGME_AUDITLOG_DIAG);

      if (diag_err)

        {

          fprintf (stderr, PGM ": getting diagnostics failed: %s\n",

                   gpgme_strerror (diag_err));

        }

      else

        {

          fputs ("Begin Diagnostics:\n", stdout);

          print_data (diag);

          fputs ("End Diagnostics.\n", stdout);

        }

      gpgme_data_release (diag);

    }

  if (err)

    {

      fprintf (stderr, PGM ": decrypt failed: %s\n", gpgme_strerror (err));

      if (result)

        print_result (result);

      exit (1);

    }

  if (result)

    {

      if (!raw_output)

        print_result (result);

      if (!raw_output)

        fputs ("Begin Output:\n", stdout);

      print_data (out);

      if (!raw_output)

        fputs ("End Output.\n", stdout);

    }

  gpgme_data_release (out);

  gpgme_data_release (in);

  gpgme_release (ctx);

  return 0;

}