/*
  this is a C++-ification of:
  GPGMEPLUG - an GPGME based cryptography plug-in following
              the common CRYPTPLUG specification.

  Copyright (C) 2001 by Klarälvdalens Datakonsult AB
  Copyright (C) 2002 g10 Code GmbH
  Copyright (C) 2004 Klarälvdalens Datakonsult AB

  GPGMEPLUG is free software; you can redistribute it and/or modify
  it under the terms of GNU General Public License as published by
  the Free Software Foundation; version 2 of the License.

  GPGMEPLUG is distributed in the hope that it will be useful,
  it under the terms of GNU General Public License as published by
  the Free Software Foundation; version 2 of the License
  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, write to the Free Software
  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "kleo/oidmap.h"

#include <gpgmepp/context.h>
#include <gpgmepp/data.h>
#include <gpgmepp/importresult.h>

/*! \file gpgmeplug.c
    \brief GPGME implementation of CRYPTPLUG following the
    specification located in common API header cryptplug.h.

    CRYPTPLUG is an independent cryptography plug-in API
    developed for Sphinx-enabeling KMail and Mutt.

    CRYPTPLUG was designed for the Aegypten project, but it may
    be used by 3rd party developers as well to design pluggable
    crypto backends for the above mentioned MUAs.

    \note All string parameters appearing in this API are to be
    interpreted as UTF-8 encoded.

    \see cryptplug.h
*/

#include <tqstring.h>

#include <string>
#include <vector>
#include <algorithm>
#include <iostream>
#include <memory>

#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <assert.h>
#include <errno.h>
#include <time.h>
#include <ctype.h>
#include <locale.h>

#define __GPGMEPLUG_ERROR_CLEARTEXT_IS_ZERO "Error: Cannot run checkMessageSignature() with cleartext == 0"

/* Note: The following specification will result in
       function encryptAndSignMessage() producing
       _empty_ mails.
       This must be changed as soon as our plugin
       is supporting the encryptAndSignMessage() function. */
#ifndef GPGMEPLUG_ENCSIGN_MAKE_MIME_OBJECT
#define GPGMEPLUG_ENCSIGN_INCLUDE_CLEARTEXT false
#define GPGMEPLUG_ENCSIGN_MAKE_MIME_OBJECT  false
#define GPGMEPLUG_ENCSIGN_MAKE_MULTI_MIME   false
#define GPGMEPLUG_ENCSIGN_CTYPE_MAIN        ""
#define GPGMEPLUG_ENCSIGN_CDISP_MAIN        ""
#define GPGMEPLUG_ENCSIGN_CTENC_MAIN        ""
#define GPGMEPLUG_ENCSIGN_CTYPE_VERSION     ""
#define GPGMEPLUG_ENCSIGN_CDISP_VERSION     ""
#define GPGMEPLUG_ENCSIGN_CTENC_VERSION     ""
#define GPGMEPLUG_ENCSIGN_BTEXT_VERSION     ""
#define GPGMEPLUG_ENCSIGN_CTYPE_CODE        ""
#define GPGMEPLUG_ENCSIGN_CDISP_CODE        ""
#define GPGMEPLUG_ENCSIGN_CTENC_CODE        ""
#define GPGMEPLUG_ENCSIGN_FLAT_PREFIX       ""
#define GPGMEPLUG_ENCSIGN_FLAT_SEPARATOR    ""
#define GPGMEPLUG_ENCSIGN_FLAT_POSTFIX      ""
#endif

#include "cryptplug.h"
#include <kdebug.h>

SMIMECryptPlug::SMIMECryptPlug() : CryptPlug() {
  GPGMEPLUG_PROTOCOL = GPGME_PROTOCOL_CMS;
  mProtocol = GpgME::Context::CMS;

  /* definitions for signing */
  // 1. opaque signatures (only used for S/MIME)
  GPGMEPLUG_OPA_SIGN_INCLUDE_CLEARTEXT = false;
  GPGMEPLUG_OPA_SIGN_MAKE_MIME_OBJECT  = true;
  GPGMEPLUG_OPA_SIGN_MAKE_MULTI_MIME   = false;
  GPGMEPLUG_OPA_SIGN_CTYPE_MAIN        = "application/pkcs7-mime; smime-type=signed-data; name=\"smime.p7m\"";
  GPGMEPLUG_OPA_SIGN_CDISP_MAIN        = "attachment; filename=\"smime.p7m\"";
  GPGMEPLUG_OPA_SIGN_CTENC_MAIN        = "base64";
  GPGMEPLUG_OPA_SIGN_CTYPE_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CDISP_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CTENC_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_BTEXT_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CTYPE_CODE        = "";
  GPGMEPLUG_OPA_SIGN_CDISP_CODE        = "";
  GPGMEPLUG_OPA_SIGN_CTENC_CODE        = "";
  GPGMEPLUG_OPA_SIGN_FLAT_PREFIX       = "";
  GPGMEPLUG_OPA_SIGN_FLAT_SEPARATOR    = "";
  GPGMEPLUG_OPA_SIGN_FLAT_POSTFIX      = "";
  // 2. detached signatures (used for S/MIME and for OpenPGP)
  GPGMEPLUG_DET_SIGN_INCLUDE_CLEARTEXT = true;
  GPGMEPLUG_DET_SIGN_MAKE_MIME_OBJECT  = true;
  GPGMEPLUG_DET_SIGN_MAKE_MULTI_MIME   = true;
  GPGMEPLUG_DET_SIGN_CTYPE_MAIN        = "multipart/signed; protocol=\"application/pkcs7-signature\"; micalg=sha1";
  GPGMEPLUG_DET_SIGN_CDISP_MAIN        = "";
  GPGMEPLUG_DET_SIGN_CTENC_MAIN        = "";
  GPGMEPLUG_DET_SIGN_CTYPE_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CDISP_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CTENC_VERSION     = "";
  GPGMEPLUG_DET_SIGN_BTEXT_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CTYPE_CODE        = "application/pkcs7-signature; name=\"smime.p7s\"";
  GPGMEPLUG_DET_SIGN_CDISP_CODE        = "attachment; filename=\"smime.p7s\"";
  GPGMEPLUG_DET_SIGN_CTENC_CODE        = "base64";
  GPGMEPLUG_DET_SIGN_FLAT_PREFIX       = "";
  GPGMEPLUG_DET_SIGN_FLAT_SEPARATOR    = "";
  GPGMEPLUG_DET_SIGN_FLAT_POSTFIX      = "";
  // 3. common definitions for opaque and detached signing
  __GPGMEPLUG_SIGNATURE_CODE_IS_BINARY = true;

  /* definitions for encoding */
  GPGMEPLUG_ENC_INCLUDE_CLEARTEXT  = false;
  GPGMEPLUG_ENC_MAKE_MIME_OBJECT   = true;
  GPGMEPLUG_ENC_MAKE_MULTI_MIME    = false;
  GPGMEPLUG_ENC_CTYPE_MAIN         = "application/pkcs7-mime; smime-type=enveloped-data; name=\"smime.p7m\"";
  GPGMEPLUG_ENC_CDISP_MAIN         = "attachment; filename=\"smime.p7m\"";
  GPGMEPLUG_ENC_CTENC_MAIN         = "base64";
  GPGMEPLUG_ENC_CTYPE_VERSION      = "";
  GPGMEPLUG_ENC_CDISP_VERSION      = "";
  GPGMEPLUG_ENC_CTENC_VERSION      = "";
  GPGMEPLUG_ENC_BTEXT_VERSION      = "";
  GPGMEPLUG_ENC_CTYPE_CODE         = "";
  GPGMEPLUG_ENC_CDISP_CODE         = "";
  GPGMEPLUG_ENC_CTENC_CODE         = "";
  GPGMEPLUG_ENC_FLAT_PREFIX        = "";
  GPGMEPLUG_ENC_FLAT_SEPARATOR     = "";
  GPGMEPLUG_ENC_FLAT_POSTFIX       = "";
  __GPGMEPLUG_ENCRYPTED_CODE_IS_BINARY = true;
}

OpenPGPCryptPlug::OpenPGPCryptPlug() : CryptPlug() {
  GPGMEPLUG_PROTOCOL = GPGME_PROTOCOL_OpenPGP;
  mProtocol = GpgME::Context::OpenPGP;

  /* definitions for signing */
  // 1. opaque signatures (only used for S/MIME)
  GPGMEPLUG_OPA_SIGN_INCLUDE_CLEARTEXT = false;
  GPGMEPLUG_OPA_SIGN_MAKE_MIME_OBJECT  = false;
  GPGMEPLUG_OPA_SIGN_MAKE_MULTI_MIME   = false;
  GPGMEPLUG_OPA_SIGN_CTYPE_MAIN        = "";
  GPGMEPLUG_OPA_SIGN_CDISP_MAIN        = "";
  GPGMEPLUG_OPA_SIGN_CTENC_MAIN        = "";
  GPGMEPLUG_OPA_SIGN_CTYPE_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CDISP_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CTENC_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_BTEXT_VERSION     = "";
  GPGMEPLUG_OPA_SIGN_CTYPE_CODE        = "";
  GPGMEPLUG_OPA_SIGN_CDISP_CODE        = "";
  GPGMEPLUG_OPA_SIGN_CTENC_CODE        = "";
  GPGMEPLUG_OPA_SIGN_FLAT_PREFIX       = "";
  GPGMEPLUG_OPA_SIGN_FLAT_SEPARATOR    = "";
  GPGMEPLUG_OPA_SIGN_FLAT_POSTFIX      = "";
  // 2. detached signatures (used for S/MIME and for OpenPGP)
  GPGMEPLUG_DET_SIGN_INCLUDE_CLEARTEXT = true;
  GPGMEPLUG_DET_SIGN_MAKE_MIME_OBJECT  = true;
  GPGMEPLUG_DET_SIGN_MAKE_MULTI_MIME   = true;
  GPGMEPLUG_DET_SIGN_CTYPE_MAIN        = "multipart/signed; protocol=\"application/pgp-signature\"; micalg=pgp-sha1";
  GPGMEPLUG_DET_SIGN_CDISP_MAIN        = "";
  GPGMEPLUG_DET_SIGN_CTENC_MAIN        = "";
  GPGMEPLUG_DET_SIGN_CTYPE_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CDISP_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CTENC_VERSION     = "";
  GPGMEPLUG_DET_SIGN_BTEXT_VERSION     = "";
  GPGMEPLUG_DET_SIGN_CTYPE_CODE        = "application/pgp-signature";
  GPGMEPLUG_DET_SIGN_CDISP_CODE        = "";
  GPGMEPLUG_DET_SIGN_CTENC_CODE        = "";
  GPGMEPLUG_DET_SIGN_FLAT_PREFIX       = "";
  GPGMEPLUG_DET_SIGN_FLAT_SEPARATOR    = "";
  GPGMEPLUG_DET_SIGN_FLAT_POSTFIX      = "";
  // 3. common definitions for opaque and detached signing
  __GPGMEPLUG_SIGNATURE_CODE_IS_BINARY = false;

  /* definitions for encoding */
  GPGMEPLUG_ENC_INCLUDE_CLEARTEXT  = false;
  GPGMEPLUG_ENC_MAKE_MIME_OBJECT   = true;
  GPGMEPLUG_ENC_MAKE_MULTI_MIME    = true;
  GPGMEPLUG_ENC_CTYPE_MAIN         = "multipart/encrypted; protocol=\"application/pgp-encrypted\"";
  GPGMEPLUG_ENC_CDISP_MAIN         = "";
  GPGMEPLUG_ENC_CTENC_MAIN         = "";
  GPGMEPLUG_ENC_CTYPE_VERSION      = "application/pgp-encrypted";
  GPGMEPLUG_ENC_CDISP_VERSION      = "attachment";
  GPGMEPLUG_ENC_CTENC_VERSION      = "";
  GPGMEPLUG_ENC_BTEXT_VERSION      = "Version: 1";
  GPGMEPLUG_ENC_CTYPE_CODE         = "application/octet-stream";
  GPGMEPLUG_ENC_CDISP_CODE         = "inline; filename=\"msg.asc\"";
  GPGMEPLUG_ENC_CTENC_CODE         = "";
  GPGMEPLUG_ENC_FLAT_PREFIX        = "";
  GPGMEPLUG_ENC_FLAT_SEPARATOR     = "";
  GPGMEPLUG_ENC_FLAT_POSTFIX       = "";
  __GPGMEPLUG_ENCRYPTED_CODE_IS_BINARY = false;
}

#define days_from_seconds(x) ((x)/86400)

/* Max number of parts in a DN */
#define MAX_GPGME_IDX 20

/* some macros to replace ctype ones and avoid locale problems */
#define spacep(p)   (*(p) == ' ' || *(p) == '\t')
#define digitp(p)   (*(p) >= '0' && *(p) <= '9')
#define hexdigitp(a) (digitp (a)                     \
                      || (*(a) >= 'A' && *(a) <= 'F')  \
                      || (*(a) >= 'a' && *(a) <= 'f'))
/* the atoi macros assume that the buffer has only valid digits */
#define atoi_1(p)   (*(p) - '0' )
#define atoi_2(p)   ((atoi_1(p) * 10) + atoi_1((p)+1))
#define atoi_4(p)   ((atoi_2(p) * 100) + atoi_2((p)+2))
#define xtoi_1(p)   (*(p) <= '9'? (*(p)- '0'): \
                     *(p) <= 'F'? (*(p)-'A'+10):(*(p)-'a'+10))
#define xtoi_2(p)   ((xtoi_1(p) * 16) + xtoi_1((p)+1))

static void *
xmalloc (size_t n)
{
  void *p = malloc (n);
  if (!p)
    {
      fputs ("\nfatal: out of core\n", stderr);
      exit (4);
    }
  return p;
}

/* Please: Don't call an allocation function xfoo when it may return NULL. */
/* Wrong: #define xstrdup( x ) (x)?strdup(x):0 */
/* Right: */
static char *
xstrdup (const char *string)
{
  char *p = (char*)xmalloc (strlen (string)+1);
  strcpy (p, string);
  return p;
}


CryptPlug::CryptPlug() {
}

CryptPlug::~CryptPlug() {
}

bool CryptPlug::initialize() {
  GpgME::setDefaultLocale( LC_CTYPE, setlocale( LC_CTYPE, 0 ) );
  GpgME::setDefaultLocale( LC_MESSAGES, setlocale( LC_MESSAGES, 0 ) );
  return (gpgme_engine_check_version (GPGMEPLUG_PROTOCOL) == GPG_ERR_NO_ERROR);
}


bool CryptPlug::hasFeature( Feature flag )
{
  /* our own plugins are supposed to support everything */
  switch ( flag ) {
  case Feature_SignMessages:
  case Feature_VerifySignatures:
  case Feature_EncryptMessages:
  case Feature_DecryptMessages:
  case Feature_SendCertificates:
  case Feature_PinEntrySettings:
  case Feature_StoreMessagesWithSigs:
  case Feature_EncryptionCRLs:
  case Feature_StoreMessagesEncrypted:
  case Feature_CheckCertificatePath:
    return true;
  case Feature_WarnSignCertificateExpiry:
  case Feature_WarnSignEmailNotInCertificate:
  case Feature_WarnEncryptCertificateExpiry:
  case Feature_WarnEncryptEmailNotInCertificate:
     return GPGMEPLUG_PROTOCOL == GPGME_PROTOCOL_CMS;
  /* undefined or not yet implemented: */
  case Feature_CRLDirectoryService:
  case Feature_CertificateDirectoryService:
  case Feature_undef:
  default:
    return false;
  }
}


static
void storeNewCharPtr( char** dest, const char* src )
{
  int sLen = strlen( src );
  *dest = (char*)xmalloc( sLen + 1 );
  strcpy( *dest, src );
}

bool CryptPlug::decryptMessage( const char* ciphertext,
                     bool        cipherIsBinary,
                     int         cipherLen,
                     const char** cleartext,
				const char* /*certificate*/,
                     int* errId,
                     char** errTxt )
{
  gpgme_ctx_t ctx;
  gpgme_error_t err;
  gpgme_data_t gCiphertext, gPlaintext;
  size_t rCLen = 0;
  char*  rCiph = 0;
  bool bOk = false;

  if( !ciphertext )
    return false;

  err = gpgme_new (&ctx);
  gpgme_set_protocol (ctx, GPGMEPLUG_PROTOCOL);

  gpgme_set_armor (ctx, cipherIsBinary ? 0 : 1);
  /*  gpgme_set_textmode (ctx, cipherIsBinary ? 0 : 1); */

  /*
  gpgme_data_new_from_mem( &gCiphertext, ciphertext,
                           1+strlen( ciphertext ), 1 ); */
  gpgme_data_new_from_mem( &gCiphertext,
                           ciphertext,
                           cipherIsBinary
                           ? cipherLen
                           : strlen( ciphertext ),
                           1 );

  gpgme_data_new( &gPlaintext );

  err = gpgme_op_decrypt( ctx, gCiphertext, gPlaintext );
  if( err ) {
    fprintf( stderr, "\ngpgme_op_decrypt() returned this error code:  %i\n\n", err );
    if( errId )
      *errId = err;
    if( errTxt ) {
      const char* _errTxt = gpgme_strerror( err );
      *errTxt = (char*)malloc( strlen( _errTxt ) + 1 );
      if( *errTxt )
        strcpy(*errTxt, _errTxt );
    }
  }

  gpgme_data_release( gCiphertext );

  rCiph = gpgme_data_release_and_get_mem( gPlaintext,  &rCLen );

  *cleartext = (char*)malloc( rCLen + 1 );
  if( *cleartext ) {
      if( rCLen ) {
          bOk = true;
          strncpy((char*)*cleartext, rCiph, rCLen );
      }
      ((char*)(*cleartext))[rCLen] = 0;
  }

  free( rCiph );
  gpgme_release( ctx );
  return bOk;
}


static char *
trim_trailing_spaces( char *string )
{
    char *p, *mark;

    for( mark = NULL, p = string; *p; p++ ) {
	if( isspace( *p ) ) {
	    if( !mark )
		mark = p;
	}
	else
	    mark = NULL;
    }
    if( mark )
	*mark = '\0' ;

    return string ;
}

/* Parse a DN and return an array-ized one.  This is not a validating
   parser and it does not support any old-stylish syntax; gpgme is
   expected to return only rfc2253 compatible strings. */
static const unsigned char *
parse_dn_part (CryptPlug::DnPair *array, const unsigned char *string)
{
  const unsigned char *s, *s1;
  size_t n;
  char *p;

  /* parse attributeType */
  for (s = string+1; *s && *s != '='; s++)
    ;
  if (!*s)
    return NULL; /* error */
  n = s - string;
  if (!n)
    return NULL; /* empty key */
  p = (char*)xmalloc (n+1);


  memcpy (p, string, n);
  p[n] = 0;
  trim_trailing_spaces ((char*)p);
  // map OIDs to their names:
  for ( unsigned int i = 0 ; i < numOidMaps ; ++i )
    if ( !strcasecmp ((char*)p, oidmap[i].oid) ) {
      free( p );
      p = xstrdup (oidmap[i].name);
      break;
    }
  array->key = p;
  string = s + 1;

  if (*string == '#')
    { /* hexstring */
      string++;
      for (s=string; hexdigitp (s); s++)
        s++;
      n = s - string;
      if (!n || (n & 1))
        return NULL; /* empty or odd number of digits */
      n /= 2;
      array->value = p = (char*)xmalloc (n+1);


      for (s1=string; n; s1 += 2, n--)
        *p++ = xtoi_2 (s1);
      *p = 0;
   }
  else
    { /* regular v3 quoted string */
      for (n=0, s=string; *s; s++)
        {
          if (*s == '\\')
            { /* pair */
              s++;
              if (*s == ',' || *s == '=' || *s == '+'
                  || *s == '<' || *s == '>' || *s == '#' || *s == ';'
                  || *s == '\\' || *s == '\"' || *s == ' ')
                n++;
              else if (hexdigitp (s) && hexdigitp (s+1))
                {
                  s++;
                  n++;
                }
              else
                return NULL; /* invalid escape sequence */
            }
          else if (*s == '\"')
            return NULL; /* invalid encoding */
          else if (*s == ',' || *s == '=' || *s == '+'
                   || *s == '<' || *s == '>' || *s == '#' || *s == ';' )
            break;
          else
            n++;
        }

      array->value = p = (char*)xmalloc (n+1);


      for (s=string; n; s++, n--)
        {
          if (*s == '\\')
            {
              s++;
              if (hexdigitp (s))
                {
                  *p++ = xtoi_2 (s);
                  s++;
                }
              else
                *p++ = *s;
            }
          else
            *p++ = *s;
        }
      *p = 0;
    }
  return s;
}


/* Parse a DN and return an array-ized one.  This is not a validating
   parser and it does not support any old-stylish syntax; gpgme is
   expected to return only rfc2253 compatible strings. */
static CryptPlug::DnPair *
parse_dn (const unsigned char *string)
{
  struct CryptPlug::DnPair *array;
  size_t arrayidx, arraysize;

  if( !string )
    return NULL;

  arraysize = 7; /* C,ST,L,O,OU,CN,email */
  arrayidx = 0;
  array = (CryptPlug::DnPair*)xmalloc ((arraysize+1) * sizeof *array);


  while (*string)
    {
      while (*string == ' ')
        string++;
      if (!*string)
        break; /* ready */
      if (arrayidx >= arraysize)
        { /* mutt lacks a real safe_realoc - so we need to copy */
          struct CryptPlug::DnPair *a2;

          arraysize += 5;
          a2 = (CryptPlug::DnPair*)xmalloc ((arraysize+1) * sizeof *array);
          for (unsigned int i=0; i < arrayidx; i++)
            {
              a2[i].key = array[i].key;
              a2[i].value = array[i].value;
            }
          free (array);
          array = a2;
        }
      array[arrayidx].key = NULL;
      array[arrayidx].value = NULL;
      string = parse_dn_part (array+arrayidx, string);
      arrayidx++;
      if (!string)
        goto failure;
      while (*string == ' ')
        string++;
      if (*string && *string != ',' && *string != ';' && *string != '+')
        goto failure; /* invalid delimiter */
      if (*string)
        string++;
    }
  array[arrayidx].key = NULL;
  array[arrayidx].value = NULL;
  return array;

 failure:
  for (unsigned i=0; i < arrayidx; i++)
    {
      free (array[i].key);
      free (array[i].value);
    }
  free (array);
  return NULL;
}

static void
add_dn_part( TQCString& result, struct CryptPlug::DnPair& dnPair )
{
  /* email hack */
  TQCString mappedPart( dnPair.key );
  for ( unsigned int i = 0 ; i < numOidMaps ; ++i ){
    if( !strcasecmp( dnPair.key, oidmap[i].oid ) ) {
      mappedPart = oidmap[i].name;
      break;
    }
  }
  result.append( mappedPart );
  result.append( "=" );
  result.append( dnPair.value );
}

static int
add_dn_parts( TQCString& result, struct CryptPlug::DnPair* dn, const char* part )
{
  int any = 0;

  if( dn ) {
    for(; dn->key; ++dn ) {
      if( !strcmp( dn->key, part ) ) {
        if( any )
          result.append( "," );
        add_dn_part( result, *dn );
        any = 1;
      }
    }
  }
  return any;
}

static char*
reorder_dn( struct CryptPlug::DnPair *dn,
            char** attrOrder = 0,
            const char* unknownAttrsHandling = 0 )
{
  struct CryptPlug::DnPair *dnOrg = dn;

  /* note: The must parts are: CN, L, OU, O, C */
  const char* defaultpart[] = {
    "CN", "S", "SN", "GN", "T", "UID",
          "MAIL", "EMAIL", "MOBILE", "TEL", "FAX", "STREET",
    "L",  "PC", "SP", "ST",
    "OU",
    "O",
    "C",
    NULL
  };
  const char** stdpart = attrOrder ? ((const char**)attrOrder) : defaultpart;
  int any=0, any2=0, found_X_=0, i;
  TQCString result;
  TQCString resultUnknowns;

  /* find and save the non-standard parts in their original order */
  if( dn ){
    for(; dn->key; ++dn ) {
      for( i = 0; stdpart[i]; ++i ) {
        if( !strcmp( dn->key, stdpart[i] ) ) {
          break;
        }
      }
      if( !stdpart[i] ) {
        if( any2 )
          resultUnknowns.append( "," );
        add_dn_part( resultUnknowns, *dn );
        any2 = 1;
      }
    }
    dn = dnOrg;
  }

  /* prepend the unknown attrs if desired */
  if( unknownAttrsHandling &&
      !strcmp(unknownAttrsHandling, "PREFIX")
      && *resultUnknowns ){
    result.append( resultUnknowns );
    any = 1;
  }else{
    any = 0;
  }

  /* add standard parts */
  for( i = 0; stdpart[i]; ++i ) {
    dn = dnOrg;
    if( any ) {
      result.append( "," );
    }
    if( any2 &&
      !strcmp(stdpart[i], "_X_") &&
      unknownAttrsHandling &&
      !strcmp(unknownAttrsHandling, "INFIX") ){
      if ( !resultUnknowns.isEmpty() ) {
        result.append( resultUnknowns );
        any = 1;
      }
      found_X_ = 1;
    }else{
      any = add_dn_parts( result, dn, stdpart[i] );
    }
  }

  /* append the unknown attrs if desired */
  if( !unknownAttrsHandling ||
      !strcmp(unknownAttrsHandling, "POSTFIX") ||
      ( !strcmp(unknownAttrsHandling, "INFIX") && !found_X_ ) ){
    if( !resultUnknowns.isEmpty() ) {
      if( any ){
        result.append( "," );
      }
      result.append( resultUnknowns );
    }
  }

  char* cResult = (char*)xmalloc( (result.length()+1)*sizeof(char) );
  if( result.isEmpty() )
    *cResult = 0;
  else
    strcpy( cResult, result );
  return cResult;
}

GpgME::ImportResult CryptPlug::importCertificateFromMem( const char* data, size_t length )
{
  using namespace GpgME;

  std::unique_ptr<Context> context( Context::createForProtocol( mProtocol ) );
  if ( !context )
    return ImportResult();

  Data keydata( data, length, false );
  if ( keydata.isNull() )
    return ImportResult();

  return context->importKeys( keydata );
}


/*  == == == == == == == == == == == == == == == == == == == == == == == == ==
   ==                                                                      ==
  ==         Continuation of CryptPlug code                               ==
 ==                                                                      ==
== == == == == == == == == == == == == == == == == == == == == == == == ==  */

// these are from gpgme-0.4.3:
static gpgme_sig_stat_t
sig_stat_from_status( gpgme_error_t err )
{
  switch ( gpg_err_code(err) ) {
  case GPG_ERR_NO_ERROR:
    return GPGME_SIG_STAT_GOOD;
  case GPG_ERR_BAD_SIGNATURE:
    return GPGME_SIG_STAT_BAD;
  case GPG_ERR_NO_PUBKEY:
    return GPGME_SIG_STAT_NOKEY;
  case GPG_ERR_NO_DATA:
    return GPGME_SIG_STAT_NOSIG;
  case GPG_ERR_SIG_EXPIRED:
    return GPGME_SIG_STAT_GOOD_EXP;
  case GPG_ERR_KEY_EXPIRED:
    return GPGME_SIG_STAT_GOOD_EXPKEY;
  default:
    return GPGME_SIG_STAT_ERROR;
  }
}


static gpgme_sig_stat_t
intersect_stati( gpgme_signature_t first )
{
  if ( !first )
    return GPGME_SIG_STAT_NONE;
  gpgme_sig_stat_t result = sig_stat_from_status( first->status );
  for ( gpgme_signature_t sig = first->next ; sig ; sig = sig->next )
    if ( sig_stat_from_status( sig->status ) != result )
      return GPGME_SIG_STAT_DIFF;
  return result;
}

static const char*
sig_status_to_string( gpgme_sig_stat_t status )
{
  const char *result;

  switch (status) {
    case GPGME_SIG_STAT_NONE:
      result = "Oops: Signature not verified";
      break;
    case GPGME_SIG_STAT_NOSIG:
      result = "No signature found";
      break;
    case GPGME_SIG_STAT_GOOD:
      result = "Good signature";
      break;
    case GPGME_SIG_STAT_BAD:
      result = "BAD signature";
      break;
    case GPGME_SIG_STAT_NOKEY:
      result = "No public key to verify the signature";
      break;
    case GPGME_SIG_STAT_ERROR:
      result = "Error verifying the signature";
      break;
    case GPGME_SIG_STAT_DIFF:
      result = "Different results for signatures";
      break;
    default:
      result = "Error: Unknown status";
      break;
  }

  return result;
}

// WARNING: if you fix a bug here, you have to likely fix it in the
// gpgme 0.3 version below, too!
static
void obtain_signature_information( gpgme_ctx_t ctx,
                                   gpgme_sig_stat_t & overallStatus,
                                   struct CryptPlug::SignatureMetaData* sigmeta,
                                   char** attrOrder,
                                   const char* unknownAttrsHandling,
                                   bool * signatureFound=0 )
{
  gpgme_error_t err;
  unsigned long sumGPGME;
  SigStatusFlags sumPlug;
  struct CryptPlug::DnPair* a;
  int sig_idx=0;

  assert( ctx );
  assert( sigmeta );

  sigmeta->extended_info = 0;
  gpgme_verify_result_t result = gpgme_op_verify_result( ctx );
  if ( !result )
    return;
  for ( gpgme_signature_t signature = result->signatures ; signature ; signature = signature->next, ++sig_idx ) {
    void* alloc_return = realloc( sigmeta->extended_info,
                                  sizeof( CryptPlug::SignatureMetaDataExtendedInfo )
                                  * ( sig_idx + 1 ) );
    if ( !alloc_return )
      break;
    sigmeta->extended_info = (CryptPlug::SignatureMetaDataExtendedInfo*)alloc_return;

    /* shorthand notation :) */
    CryptPlug::SignatureMetaDataExtendedInfo & this_info = sigmeta->extended_info[sig_idx];

    /* clear the data area */
    memset( &this_info, 0, sizeof (CryptPlug::SignatureMetaDataExtendedInfo) );

    /* the creation time */
    if ( signature->timestamp ) {
      this_info.creation_time = (tm*)malloc( sizeof( struct tm ) );
      if ( this_info.creation_time ) {
        struct tm * ctime_val = localtime( (time_t*)&signature->timestamp );
        memcpy( this_info.creation_time,
                ctime_val, sizeof( struct tm ) );
      }
    }

    /* the extended signature verification status */
    sumGPGME = signature->summary;
    fprintf( stderr, "gpgmeplug checkMessageSignature status flags: %lX\n", sumGPGME );
    /* translate GPGME status flags to common CryptPlug status flags */
    sumPlug = 0;
#define convert(X) if ( sumGPGME & GPGME_SIGSUM_##X ) sumPlug |= SigStat_##X
    convert(VALID);
    convert(GREEN);
    convert(RED);
    convert(KEY_REVOKED);
    convert(KEY_EXPIRED);
    convert(SIG_EXPIRED);
    convert(KEY_MISSING);
    convert(CRL_MISSING);
    convert(CRL_TOO_OLD);
    convert(BAD_POLICY);
    convert(SYS_ERROR);
#undef convert
    if( sumGPGME && !sumPlug )
      sumPlug = SigStat_NUMERICAL_CODE | sumGPGME;
    this_info.sigStatusFlags = sumPlug;

    /* extract finger print */
    if ( signature->fpr )
      storeNewCharPtr( &this_info.fingerprint, signature->fpr );

    /* validity */
    this_info.validity = GPGME_VALIDITY_UNKNOWN;

    /* sig key data */
    gpgme_key_t key = 0;
    // PENDING(marc) if this is deprecated, how shall we get at all
    // the infos below?
    err = gpgme_get_sig_key (ctx, sig_idx, &key);

    if ( !err && key ) {
      const char* attr_string;
      unsigned long attr_ulong;

      /* extract key identidy */
      attr_string = key->subkeys ? key->subkeys->keyid : 0 ;
      if ( attr_string )
	storeNewCharPtr( &this_info.keyid, attr_string );

      /* pubkey algorithm */
      attr_string = key->subkeys ? gpgme_pubkey_algo_name( key->subkeys->pubkey_algo ) : 0 ;
      if (attr_string != 0)
	storeNewCharPtr( &this_info.algo, attr_string );
      attr_ulong = key->subkeys ? key->subkeys->pubkey_algo : 0 ;
      this_info.algo_num = attr_ulong;

      /* extract key validity */
      attr_ulong = key->uids ? key->uids->validity : 0 ;
      this_info.validity = attr_ulong;

      /* extract user id, according to the documentation it's representable
       * as a number, but it seems that it also has a string representation
       */
      attr_string = key->uids ? key->uids->uid : 0 ;
      if (attr_string != 0) {
        a = parse_dn( (const unsigned char*)attr_string );
        this_info.userid = reorder_dn( a, attrOrder, unknownAttrsHandling );
      }

      attr_ulong = 0;
      this_info.userid_num = attr_ulong;

      /* extract the length */
      this_info.keylen = key->subkeys ? key->subkeys->length : 0 ;

      /* extract the creation time of the key */
      attr_ulong = key->subkeys ? key->subkeys->timestamp : 0 ;
      this_info.key_created = attr_ulong;

      /* extract the expiration time of the key */
      attr_ulong = key->subkeys ? key->subkeys->expires : 0 ;
      this_info.key_expires = attr_ulong;

      /* extract user name */
      attr_string = key->uids ? key->uids->name : 0 ;
      if (attr_string != 0) {
        a = parse_dn( (const unsigned char*)attr_string );
        this_info.name = reorder_dn( a, attrOrder, unknownAttrsHandling );
      }

      /* extract email(s) */
      this_info.emailCount = 0;
      this_info.emailList = 0;
      for ( gpgme_user_id_t uid = key->uids ; uid ; uid = uid->next ) {
        attr_string = uid->email;
        if ( attr_string && *attr_string) {
          fprintf( stderr, "gpgmeplug checkMessageSignature found email: %s\n", attr_string );
          if( !this_info.emailCount )
            alloc_return = malloc( sizeof( char*) );
          else
            alloc_return = realloc( this_info.emailList,
                  sizeof( char*)
                  * (this_info.emailCount + 1) );
          if( alloc_return ) {
            this_info.emailList = (char**)alloc_return;
            storeNewCharPtr( &( this_info.emailList[ this_info.emailCount ] ),
                attr_string );
            ++this_info.emailCount;
          }
        }
      }
      if( !this_info.emailCount )
	fprintf( stderr, "gpgmeplug checkMessageSignature found NO EMAIL\n" );

      /* extract the comment */
      attr_string = key->uids ? key->uids->comment : 0 ;
      if (attr_string != 0)
	storeNewCharPtr( &this_info.comment, attr_string );
    }

    gpgme_sig_stat_t status = sig_stat_from_status( signature->status );
    const char* sig_status = sig_status_to_string( status );
    storeNewCharPtr( &this_info.status_text, sig_status );
  }
  sigmeta->extended_info_count = sig_idx;
  overallStatus = intersect_stati( result->signatures );
  sigmeta->status_code = overallStatus;
  storeNewCharPtr( &sigmeta->status, sig_status_to_string( overallStatus ) );
  if ( signatureFound )
    *signatureFound = ( overallStatus != GPGME_SIG_STAT_NONE );
}

bool CryptPlug::checkMessageSignature( char** cleartext,
                            const char* signaturetext,
                            bool signatureIsBinary,
                            int signatureLen,
                            struct CryptPlug::SignatureMetaData* sigmeta,
                            char** attrOrder,
                            const char* unknownAttrsHandling )
{
  gpgme_ctx_t ctx;
  gpgme_sig_stat_t status = GPGME_SIG_STAT_NONE;
  gpgme_data_t datapart, sigpart;
  char* rClear = 0;
  size_t clearLen;
  bool isOpaqueSigned;

  if( !cleartext ) {
    if( sigmeta )
      storeNewCharPtr( &sigmeta->status,
                        __GPGMEPLUG_ERROR_CLEARTEXT_IS_ZERO );

    return false;
  }

  isOpaqueSigned = !*cleartext;

  gpgme_new( &ctx );
  gpgme_set_protocol (ctx, GPGMEPLUG_PROTOCOL);
  gpgme_set_armor (ctx,    signatureIsBinary ? 0 : 1);
  /*  gpgme_set_textmode (ctx, signatureIsBinary ? 0 : 1); */

  if( isOpaqueSigned )
    gpgme_data_new( &datapart );
  else
    gpgme_data_new_from_mem( &datapart, *cleartext,
                             strlen( *cleartext ), 1 );

  gpgme_data_new_from_mem( &sigpart,
                           signaturetext,
                           signatureIsBinary
                           ? signatureLen
                           : strlen( signaturetext ),
                           1 );

  if ( isOpaqueSigned )
    gpgme_op_verify( ctx, sigpart, 0, datapart );
  else
    gpgme_op_verify( ctx, sigpart, datapart, 0 );

  if( isOpaqueSigned ) {
    rClear = gpgme_data_release_and_get_mem( datapart, &clearLen );
    *cleartext = (char*)malloc( clearLen + 1 );
    if( *cleartext ) {
      if( clearLen )
        strncpy(*cleartext, rClear, clearLen );
      (*cleartext)[clearLen] = '\0';
    }
    free( rClear );
  }
  else
    gpgme_data_release( datapart );

  gpgme_data_release( sigpart );

  obtain_signature_information( ctx, status, sigmeta,
                                attrOrder, unknownAttrsHandling );

  gpgme_release( ctx );
  return ( status == GPGME_SIG_STAT_GOOD );
}

bool CryptPlug::decryptAndCheckMessage( const char*  ciphertext,
                                  bool         cipherIsBinary,
                                  int          cipherLen,
                                  const char** cleartext,
                                  const char*  /*certificate*/,
                                  bool*        signatureFound,
                                  struct CryptPlug::SignatureMetaData* sigmeta,
                                  int*   errId,
                                  char** errTxt,
                                  char** attrOrder,
                                  const char* unknownAttrsHandling  )
{
  gpgme_ctx_t ctx;
  gpgme_error_t err;
  gpgme_decrypt_result_t decryptresult;
  gpgme_data_t gCiphertext, gPlaintext;
  gpgme_sig_stat_t sigstatus = GPGME_SIG_STAT_NONE;
  size_t rCLen = 0;
  char*  rCiph = 0;
  bool bOk = false;

  if( !ciphertext )
    return false;

  err = gpgme_new (&ctx);
  gpgme_set_protocol (ctx, GPGMEPLUG_PROTOCOL);

  gpgme_set_armor (ctx, cipherIsBinary ? 0 : 1);
  /*  gpgme_set_textmode (ctx, cipherIsBinary ? 0 : 1); */

  /*
  gpgme_data_new_from_mem( &gCiphertext, ciphertext,
                           1+strlen( ciphertext ), 1 ); */
  gpgme_data_new_from_mem( &gCiphertext,
                           ciphertext,
                           cipherIsBinary
                           ? cipherLen
                           : strlen( ciphertext ),
                           1 );

  gpgme_data_new( &gPlaintext );

  err = gpgme_op_decrypt_verify( ctx, gCiphertext, gPlaintext );
  gpgme_data_release( gCiphertext );

  if( err ) {
    fprintf( stderr, "\ngpgme_op_decrypt_verify() returned this error code:  %i\n\n", err );
    if( errId )
      *errId = err;
    if( errTxt ) {
      const char* _errTxt = gpgme_strerror( err );
      *errTxt = (char*)malloc( strlen( _errTxt ) + 1 );
      if( *errTxt )
        strcpy(*errTxt, _errTxt );
    }
    gpgme_data_release( gPlaintext );
    gpgme_release( ctx );
    return bOk;
  }
  decryptresult = gpgme_op_decrypt_result( ctx );

  bool bWrongKeyUsage = false;
#ifdef HAVE_GPGME_WRONG_KEY_USAGE
  if( decryptresult && decryptresult->wrong_key_usage )
    bWrongKeyUsage = true;
#endif

  if( bWrongKeyUsage ) {
    if( errId )
      *errId = CRYPTPLUG_ERR_WRONG_KEY_USAGE; // report the wrong key usage
  }

  rCiph = gpgme_data_release_and_get_mem( gPlaintext,  &rCLen );

  *cleartext = (char*)malloc( rCLen + 1 );
  if( *cleartext ) {
      if( rCLen ) {
          bOk = true;
          strncpy((char*)*cleartext, rCiph, rCLen );
      }
      ((char*)(*cleartext))[rCLen] = 0;
  }
  free( rCiph );

  obtain_signature_information( ctx, sigstatus, sigmeta,
                                attrOrder, unknownAttrsHandling,
                                signatureFound );

  gpgme_release( ctx );
  return bOk;
}

