/***************************************************************************
    begin       : Sat Dec 16 2012
    copyright   : (C) 2012 by Martin Preuss
    email       : martin@libchipcard.de

 ***************************************************************************
 *                                                                         *
 *   This library 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.    *
 *                                                                         *
 *   This library 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 library; if not, write to the Free Software   *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 *                                                                         *
 ***************************************************************************/


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

#include "passwdstore_p.h"
#include "i18n_l.h"

#include <gwenhywfar/gui.h>
#include <gwenhywfar/db.h>
#include <gwenhywfar/directory.h>
#include <gwenhywfar/fslock.h>
#include <gwenhywfar/mdigest.h>
#include <gwenhywfar/text.h>
#include <gwenhywfar/debug.h>
#include <gwenhywfar/smalltresor.h>

#include <errno.h>



GWEN_PASSWD_STORE *GWEN_PasswordStore_new(const char *fname) {
  GWEN_PASSWD_STORE *sto;

  GWEN_NEW_OBJECT(GWEN_PASSWD_STORE, sto);
  if (fname)
    sto->fileName=strdup(fname);
  sto->dbPasswords=NULL;

  return sto;
}



void GWEN_PasswordStore_free(GWEN_PASSWD_STORE *sto) {
  if (sto) {
    memset(sto->pw, 0, sizeof(sto->pw));
    if (sto->dbPasswords) {
      GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);
      GWEN_DB_Group_free(sto->dbPasswords);
      sto->dbPasswords=NULL;
    }
    free(sto->fileName);
    GWEN_FREE_OBJECT(sto);
  }
}



void GWEN_PasswordStore_ClearStoragePasswd(GWEN_PASSWD_STORE *sto) {
  assert(sto);
  memset(sto->pw, 0, GWEN_PASSWDSTORE_PWLEN);
  if (sto->dbPasswords) {
    GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);
    GWEN_DB_Group_free(sto->dbPasswords);
    sto->dbPasswords=NULL;
  }
}




static int readFile(const char *fname, GWEN_BUFFER *dbuf) {
  FILE *f;

  f=fopen(fname, "rb");
  if (f) {
    while(!feof(f)) {
      uint32_t l;
      ssize_t s;
      char *p;

      GWEN_Buffer_AllocRoom(dbuf, 1024);
      l=GWEN_Buffer_GetMaxUnsegmentedWrite(dbuf);
      p=GWEN_Buffer_GetPosPointer(dbuf);
      s=fread(p, 1, l, f);
      if (s==0)
        break;
      if (s==(ssize_t)-1) {
        DBG_ERROR(GWEN_LOGDOMAIN,
                  "fread(%s): %s",
                  fname, strerror(errno));
        fclose(f);
        return GWEN_ERROR_IO;
      }

      GWEN_Buffer_IncrementPos(dbuf, s);
      GWEN_Buffer_AdjustUsedBytes(dbuf);
    }

    fclose(f);
    return 0;
  }
  else {
    if (errno==ENOENT) {
      DBG_INFO(GWEN_LOGDOMAIN, "File [%s] does not exist", fname);
      return GWEN_ERROR_NOT_FOUND;
    }
    else {
      DBG_ERROR(GWEN_LOGDOMAIN,
                "fopen(%s): %s",
                fname, strerror(errno));
      return GWEN_ERROR_IO;
    }
  }
}



static int writeToFile(FILE *f, const char *p, int len) {
  while(len>0) {
    ssize_t l;
    ssize_t s;

    l=1024;
    if (l>len)
      l=len;
    s=fwrite(p, 1, l, f);
    if (s==(ssize_t)-1 || s==0) {
      DBG_ERROR(GWEN_LOGDOMAIN,
                "fwrite: %s",
                strerror(errno));
      return GWEN_ERROR_IO;
    }
    p+=s;
    len-=s;
  }

  return 0;
}



static int writeFile(const char *fname, const char *p, int len) {
  FILE *f;

  f=fopen(fname, "wb");
  if (f) {
    int rv;

    rv=writeToFile(f, p, len);
    if (rv<0) {
      DBG_ERROR(GWEN_LOGDOMAIN, "here (%d)", rv);
      fclose(f);
      return rv;
    }
    if (fclose(f)) {
      DBG_ERROR(GWEN_LOGDOMAIN, "here (%d)", rv);
      return rv;
    }
  }
  else {
    DBG_ERROR(GWEN_LOGDOMAIN, "fopen(%s): %s",
              fname, strerror(errno));
    return GWEN_ERROR_IO;
  }

  return 0;
}



static int GWEN_PasswordStore_Digest(const uint8_t *t, uint32_t size, GWEN_BUFFER *buf) {
  GWEN_MDIGEST *md;
  int rv;

  /* hash token and pin */
  md=GWEN_MDigest_Rmd160_new();
  rv=GWEN_MDigest_Begin(md);
  if (rv==0)
    rv=GWEN_MDigest_Update(md, (const uint8_t*)t, size);
  if (rv==0)
    rv=GWEN_MDigest_End(md);
  if (rv<0) {
    DBG_ERROR(GWEN_LOGDOMAIN, "Hash error (%d)", rv);
    GWEN_MDigest_free(md);
    return rv;
  }

  GWEN_Buffer_AppendBytes(buf,
                          (const char*)GWEN_MDigest_GetDigestPtr(md),
                          GWEN_MDigest_GetDigestSize(md));
  GWEN_MDigest_free(md);
  return 0;
}



static int GWEN_PasswordStore_CheckDigest(const uint8_t *t, uint32_t size, const uint8_t *h) {
  GWEN_MDIGEST *md;
  int rv;

  /* hash token and pin */
  md=GWEN_MDigest_Rmd160_new();
  rv=GWEN_MDigest_Begin(md);
  if (rv==0)
    rv=GWEN_MDigest_Update(md, (const uint8_t*)t, size);
  if (rv==0)
    rv=GWEN_MDigest_End(md);
  if (rv<0) {
    DBG_ERROR(GWEN_LOGDOMAIN, "Hash error (%d)", rv);
    GWEN_MDigest_free(md);
    return rv;
  }

  if (memcmp(h, GWEN_MDigest_GetDigestPtr(md), 20)) {
    DBG_ERROR(GWEN_LOGDOMAIN, "Bad hash");
    GWEN_MDigest_free(md);
    return GWEN_ERROR_BAD_DATA;
  }

  GWEN_MDigest_free(md);
  return 0;
}



static void GWEN_PasswordStore_SafeFreeDb(GWEN_PASSWD_STORE *sto) {
  if (sto->dbPasswords) {
    GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);
    GWEN_DB_Group_free(sto->dbPasswords);
    sto->dbPasswords=NULL;
  }
}



static int GWEN_PasswordStore_ReadDecryptFile(GWEN_PASSWD_STORE *sto, GWEN_BUFFER *secbuf) {
  int rv;
  GWEN_BUFFER *sbuf;

  sbuf=GWEN_Buffer_new(0, 256, 0, 1);
  rv=readFile(sto->fileName, sbuf);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_free(sbuf);
    return rv;
  }

  if (GWEN_Buffer_GetUsedBytes(sbuf)<1) {
    DBG_INFO(GWEN_LOGDOMAIN, "Empty file");
    GWEN_Buffer_free(sbuf);
    return GWEN_ERROR_NO_DATA;
  }

  for (;;) {
    GWEN_BUFFER *tbuf;
    uint32_t pos1;
    uint32_t pos2;
    uint32_t len;

    tbuf=GWEN_Buffer_new(0, 256, 0, 1);
    GWEN_Buffer_AppendString(tbuf, "PASSWORD_STORE_");
    GWEN_Text_UnescapeToBufferTolerant(sto->fileName, tbuf);

    if (sto->pw[0]==0) {
      rv=GWEN_Gui_InputBox(GWEN_GUI_INPUT_FLAGS_DIRECT,
                           I18N("Enter Password"),
                           I18N("Please enter the password for the password store.\n"
                                "<html>"
                                "Please enter the password for the <b>password store</b>.</br>"
                                "</html>"),
                           sto->pw,
                           4,
                           sizeof(sto->pw)-1,
                           0);
      if (rv<0) {
        DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
        GWEN_Buffer_free(tbuf);
        GWEN_Buffer_free(sbuf);
        return rv;
      }
    }

    pos1=GWEN_Buffer_GetPos(secbuf);

    rv=GWEN_SmallTresor_Decrypt((const uint8_t*) GWEN_Buffer_GetStart(sbuf),
                                GWEN_Buffer_GetUsedBytes(sbuf),
                                sto->pw,
                                secbuf,
                                GWEN_PASSWDSTORE_PW_ITERATIONS,
                                GWEN_PASSWDSTORE_CRYPT_ITERATIONS);
    GWEN_Buffer_free(tbuf);
    if (rv<0) {
      DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
      /* error, reset password */
      memset(sto->pw, 0, sizeof(sto->pw));
    }
    else {
      /* check and remove hash */
      pos2=GWEN_Buffer_GetPos(secbuf);
      len=pos2-pos1;

      if (len>=20) {
        const uint8_t *p1;
        const uint8_t *p2;

        p1=(const uint8_t*)GWEN_Buffer_GetStart(secbuf)+pos1;      /* start of decrypted data */
        p2=(const uint8_t*)GWEN_Buffer_GetStart(secbuf)+(pos2-20); /* start of hash */

        rv=GWEN_PasswordStore_CheckDigest(p1, len-20, p2);
        if (rv<0) {
          DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
          GWEN_Buffer_free(sbuf);
          return rv;
        }
        else {
          GWEN_Buffer_Crop(secbuf, 0, pos2-20);
          break;
        }
      }
      else {
        DBG_ERROR(GWEN_LOGDOMAIN, "Bad data size (smaller than 20 bytes)");
        /* reset buffer */
        GWEN_Buffer_Crop(secbuf, 0, pos1);
        GWEN_Buffer_free(sbuf);
        return rv;
      }
    }
  } /* for */

  GWEN_Buffer_free(sbuf);

  return 0;
}



static int GWEN_PasswordStore_EncryptWriteFile(GWEN_PASSWD_STORE *sto, const uint8_t *sec, uint32_t len) {
  int rv;
  GWEN_BUFFER *sbuf;
  GWEN_BUFFER *tbuf;

  /* make sure the data dir exists */
  DBG_ERROR(0, "Looking for [%s]", sto->fileName);
  rv=GWEN_Directory_GetPath(sto->fileName, GWEN_PATH_FLAGS_VARIABLE);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    return rv;
  }

  tbuf=GWEN_Buffer_new(0, 256, 0, 1);
  GWEN_Buffer_AppendString(tbuf, "PASSWORD_STORE_");
  GWEN_Text_UnescapeToBufferTolerant(sto->fileName, tbuf);

  /* ask for passwd if not already set */
  if (sto->pw[0]==0) {
    if (sto->isNew) {
      rv=GWEN_Gui_InputBox(GWEN_GUI_INPUT_FLAGS_DIRECT | GWEN_GUI_INPUT_FLAGS_CONFIRM,
                           I18N("Create New Password Store"),
                           I18N(
                             "You are about to create a new password store.\n"
                             "Passwords you store here will be encrypted with a passphrase\n"
                             "which you must enter now.\n"
                             "\n"

                             "Later you will only need to remember the passphrase for the\n"
                             "password store, not all the individuell passwords.\n"
                             "\n"
                             "WARNING: Storing your passwords in the password store\n"
                             "can be considered a security risk, especially if the passphrase protecting it\n"
                             "is not strong enough!\n"
                             "\n"
                             "You can safely abort this step, in which case your passwords will not be stored.\n"
                             "\n"
                             "Please enter the passphrase for the password store to be created or abort.\n"
                             "<html>"
                             "<p>You are about to create a new <b>password store</b>.</p>"
                             "<br>"
                             "<p>Passwords you store here will be encrypted with a passphrase "
                             "which you must enter now.</p>"
                             "<p>Later you will only need to remember the passphrase for the "
                             "password store, not all the individuell passwords.<p>"
                             "<p><font color=\"red\">"
                             "<b>Warning:</b> Storing your passwords in the password store "
                             "can be considered a <b>security risk</b>, especially if the passphrase protecting it "
                             "is not strong enough!"
                             "</font></p>"
                             "<p><b>You can safely abort this step</b>, in which case your passwords will not be stored.</p>"
                             "<br>"
                             "<p>Please enter the passphrase for the password store to be created or abort.</p>"
                             "</html>"),
                           sto->pw,
                           4,
                           sizeof(sto->pw)-1,
                           0);

    }
    else
      rv=GWEN_Gui_InputBox(GWEN_GUI_INPUT_FLAGS_DIRECT,
                           I18N("Enter Password"),
                           I18N("Please enter the password for the password store.\n"
                                "<html>"
                                "Please enter the password for the <b>password store</b>.</br>"
                                "</html>"),
                           sto->pw,
                           4,
                           sizeof(sto->pw)-1,
                           0);
    if (rv<0) {
      DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
      GWEN_Buffer_free(tbuf);
      return rv;
    }
  }

  GWEN_Buffer_free(tbuf);

  /* prepare data to write */
  sbuf=GWEN_Buffer_new(0, 256, 0, 1);
  tbuf=GWEN_Buffer_new(0, len+20, 0, 1);

  /* add clear text data */
  GWEN_Buffer_AppendBytes(tbuf, (const char*) sec, len);

  /* add hash (20 bytes) */
  rv=GWEN_PasswordStore_Digest((const uint8_t*) sec, len, tbuf);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_free(tbuf);
    GWEN_Buffer_free(sbuf);
    return rv;
  }

  /* encrypt cleartext */
  rv=GWEN_SmallTresor_Encrypt((const uint8_t*) GWEN_Buffer_GetStart(tbuf),
                              GWEN_Buffer_GetUsedBytes(tbuf),
                              sto->pw,
                              sbuf,
                              GWEN_PASSWDSTORE_PW_ITERATIONS,
                              GWEN_PASSWDSTORE_CRYPT_ITERATIONS);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_free(tbuf);
    GWEN_Buffer_free(sbuf);
    return rv;
  }
  GWEN_Buffer_OverwriteContent(tbuf, 0);
  GWEN_Buffer_free(tbuf);

  /* write file */
  rv=writeFile(sto->fileName,
               GWEN_Buffer_GetStart(sbuf),
               GWEN_Buffer_GetUsedBytes(sbuf));
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_free(sbuf);
    return rv;
  }

  GWEN_Buffer_free(sbuf);

  return 0;
}




static int GWEN_PasswordStore_ReadFile(GWEN_PASSWD_STORE *sto) {
  GWEN_BUFFER *tbuf;
  int rv;

  tbuf=GWEN_Buffer_new(0, 256, 0, 1);

  rv=GWEN_PasswordStore_ReadDecryptFile(sto, tbuf);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_free(tbuf);
    return rv;
  }
  sto->isNew=0;

  GWEN_PasswordStore_SafeFreeDb(sto);

  sto->dbPasswords=GWEN_DB_Group_new("passwords");
  rv=GWEN_DB_ReadFromString(sto->dbPasswords,
                            GWEN_Buffer_GetStart(tbuf),
                            GWEN_Buffer_GetUsedBytes(tbuf),
                            GWEN_DB_FLAGS_DEFAULT);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_Buffer_OverwriteContent(tbuf, 0);
    GWEN_Buffer_free(tbuf);
    return rv;
  }
  GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);

  GWEN_Buffer_OverwriteContent(tbuf, 0);
  GWEN_Buffer_free(tbuf);
  return 0;
}



static int GWEN_PasswordStore_WriteFile(GWEN_PASSWD_STORE *sto) {
  if (sto->dbPasswords) {
    GWEN_BUFFER *tbuf;
    int rv;

    tbuf=GWEN_Buffer_new(0, 256, 0, 1);
    rv=GWEN_DB_WriteToBuffer(sto->dbPasswords, tbuf, GWEN_DB_FLAGS_DEFAULT);
    if (rv<0) {
      DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
      GWEN_Buffer_OverwriteContent(tbuf, 0);
      GWEN_Buffer_free(tbuf);
      return rv;
    }

    rv=GWEN_PasswordStore_EncryptWriteFile(sto,
                                           (const uint8_t*) GWEN_Buffer_GetStart(tbuf),
                                           GWEN_Buffer_GetUsedBytes(tbuf));
    if (rv<0) {
      DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
      GWEN_Buffer_OverwriteContent(tbuf, 0);
      GWEN_Buffer_free(tbuf);
      return rv;
    }

    GWEN_Buffer_OverwriteContent(tbuf, 0);
    GWEN_Buffer_free(tbuf);
    return 0;
  }
  else {
    DBG_INFO(GWEN_LOGDOMAIN, "No password db");
    return GWEN_ERROR_INTERNAL;
  }
}




static int GWEN_PasswordStore__SetPassword(GWEN_PASSWD_STORE *sto, const char *token, const char *secret) {
  GWEN_BUFFER *buf;

  buf=GWEN_Buffer_new(0, 64, 0, 1);
  GWEN_Text_EscapeToBufferTolerant(token, buf);

  if (secret==NULL)
    GWEN_DB_DeleteVar(sto->dbPasswords, GWEN_Buffer_GetStart(buf));
  else
    GWEN_DB_SetCharValue(sto->dbPasswords, GWEN_DB_FLAGS_OVERWRITE_VARS,
                         GWEN_Buffer_GetStart(buf), secret);
  GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);
  GWEN_Buffer_free(buf);

  return 0;
}



static int GWEN_PasswordStore__GetPassword(GWEN_PASSWD_STORE *sto, const char *token, char *buffer, int minLen, int maxLen) {
  GWEN_BUFFER *buf;
  const char *s;

  buf=GWEN_Buffer_new(0, 256, 0, 1);
  GWEN_Text_EscapeToBufferTolerant(token, buf);

  s=GWEN_DB_GetCharValue(sto->dbPasswords,
                         GWEN_Buffer_GetStart(buf),
                         0, NULL);
  if (s) {
    int i;

    i=strlen(s);
    if (i>=minLen && i < maxLen) {
      memmove(buffer, s, i+1);
      GWEN_Buffer_free(buf);
      return 0;
    }
    else {
      DBG_ERROR(GWEN_LOGDOMAIN, "Stored password [%s] is not within size limits (%d), rejecting.",
                GWEN_Buffer_GetStart(buf), i);
    }
  }

  GWEN_Buffer_free(buf);
  return GWEN_ERROR_NOT_FOUND;
}





int GWEN_PasswordStore_SetPassword(GWEN_PASSWD_STORE *sto, const char *token, const char *secret) {
  GWEN_FSLOCK *lck;
  GWEN_FSLOCK_RESULT rs;
  int rv;

  /* make sure path exists */
  rv=GWEN_Directory_GetPath(sto->fileName, GWEN_PATH_FLAGS_VARIABLE);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    return rv;
  }

  /* lock file */
  lck=GWEN_FSLock_new(sto->fileName, GWEN_FSLock_TypeFile);
  rs=GWEN_FSLock_Lock(lck, 60*1000, 0);
  if (rs!=GWEN_FSLock_ResultOk) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rs);
    return GWEN_ERROR_IO;
  }

  /* read and decrypt file */
  rv=GWEN_PasswordStore_ReadFile(sto);
  if (rv<0) {
    if (rv==GWEN_ERROR_NOT_FOUND || rv==GWEN_ERROR_NO_DATA) {
      DBG_INFO(GWEN_LOGDOMAIN, "Will create password store [%s]", sto->fileName);
      if (sto->dbPasswords==NULL) {
        sto->dbPasswords=GWEN_DB_Group_new("passwords");
        GWEN_DB_ModifyBranchFlagsDown(sto->dbPasswords, GWEN_DB_NODE_FLAGS_SAFE, GWEN_DB_NODE_FLAGS_SAFE);
      }
      sto->isNew=1;
    }
    else {
      DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
      GWEN_FSLock_Unlock(lck);
      GWEN_FSLock_free(lck);
      return rv;
    }
  }

  /* set password in db */
  rv=GWEN_PasswordStore__SetPassword(sto, token, secret);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_FSLock_Unlock(lck);
    GWEN_FSLock_free(lck);
    return rv;
  }

  /* write file back */
  rv=GWEN_PasswordStore_WriteFile(sto);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_FSLock_Unlock(lck);
    GWEN_FSLock_free(lck);
    return rv;
  }

  /* unlock file */
  GWEN_FSLock_Unlock(lck);
  GWEN_FSLock_free(lck);

  /* release passwords */
  GWEN_PasswordStore_SafeFreeDb(sto);

  return 0;
}




int GWEN_PasswordStore_GetPassword(GWEN_PASSWD_STORE *sto, const char *token, char *buffer, int minLen, int maxLen) {
  int rv;
  GWEN_FSLOCK *lck;
  GWEN_FSLOCK_RESULT rs;

  /* make sure path exists */
  rv=GWEN_Directory_GetPath(sto->fileName, GWEN_PATH_FLAGS_VARIABLE);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    return rv;
  }

  /* lock file */
  lck=GWEN_FSLock_new(sto->fileName, GWEN_FSLock_TypeFile);
  rs=GWEN_FSLock_Lock(lck, 60*1000, 0);
  if (rs!=GWEN_FSLock_ResultOk) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rs);
    return GWEN_ERROR_IO;
  }

  /* read and decode file */
  rv=GWEN_PasswordStore_ReadFile(sto);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    GWEN_FSLock_Unlock(lck);
    GWEN_FSLock_free(lck);
    return rv;
  }

  /* unlock file */
  GWEN_FSLock_Unlock(lck);
  GWEN_FSLock_free(lck);

  /* finally get password, if possible */
  rv=GWEN_PasswordStore__GetPassword(sto, token, buffer, minLen, maxLen);
  if (rv<0) {
    DBG_INFO(GWEN_LOGDOMAIN, "here (%d)", rv);
    return rv;
  }

  /* release passwords */
  GWEN_PasswordStore_SafeFreeDb(sto);

  return 0;
}




