/**

 * WinPR: Windows Portable Runtime

 * Windows Registry (.reg file format)

 *

 * Copyright 2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <winpr/config.h>

#include <winpr/path.h>

#include <errno.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <winpr/wtypes.h>

#include <winpr/string.h>

#include <winpr/assert.h>

#include <winpr/crt.h>

#include <winpr/file.h>

#include "registry_reg.h"

#include "../log.h"

#define TAG WINPR_TAG("registry")

struct reg_data_type

{

  char* tag;

  size_t length;

  DWORD type;

};

static struct reg_data_type REG_DATA_TYPE_TABLE[] = { { "\"", 1, REG_SZ },

                                                    { "dword:", 6, REG_DWORD },

                                                    { "str:\"", 5, REG_SZ },

                                                    { "str(2):\"", 8, REG_EXPAND_SZ },

                                                    { "str(7):\"", 8, REG_MULTI_SZ },

                                                    { "hex:", 4, REG_BINARY },

                                                    { "hex(2):\"", 8, REG_EXPAND_SZ },

                                                    { "hex(7):\"", 8, REG_MULTI_SZ },

                                                    { "hex(b):\"", 8, REG_QWORD } };

static char* reg_data_type_string(DWORD type)

{

  switch (type)

  {

    case REG_NONE:

      return "REG_NONE";

    case REG_SZ:

      return "REG_SZ";

    case REG_EXPAND_SZ:

      return "REG_EXPAND_SZ";

    case REG_BINARY:

      return "REG_BINARY";

    case REG_DWORD:

      return "REG_DWORD";

    case REG_DWORD_BIG_ENDIAN:

      return "REG_DWORD_BIG_ENDIAN";

    case REG_LINK:

      return "REG_LINK";

    case REG_MULTI_SZ:

      return "REG_MULTI_SZ";

    case REG_RESOURCE_LIST:

      return "REG_RESOURCE_LIST";

    case REG_FULL_RESOURCE_DESCRIPTOR:

      return "REG_FULL_RESOURCE_DESCRIPTOR";

    case REG_RESOURCE_REQUIREMENTS_LIST:

      return "REG_RESOURCE_REQUIREMENTS_LIST";

    case REG_QWORD:

      return "REG_QWORD";

    default:

      return "REG_UNKNOWN";

  }

}

static BOOL reg_load_start(Reg* reg)

{

  char* buffer = NULL;

  INT64 file_size = 0;

  WINPR_ASSERT(reg);

  WINPR_ASSERT(reg->fp);

  if (_fseeki64(reg->fp, 0, SEEK_END) != 0)

    return FALSE;

  file_size = _ftelli64(reg->fp);

  if (_fseeki64(reg->fp, 0, SEEK_SET) != 0)

    return FALSE;

  reg->line = NULL;

  reg->next_line = NULL;

  if (file_size < 1)

    return FALSE;

  buffer = (char*)realloc(reg->buffer, (size_t)file_size + 2);

  if (!buffer)

    return FALSE;

  reg->buffer = buffer;

  if (fread(reg->buffer, (size_t)file_size, 1, reg->fp) != 1)

    return FALSE;

  reg->buffer[file_size] = '\n';

  reg->buffer[file_size + 1] = '\0';

  reg->next_line = strtok_s(reg->buffer, "\n", &reg->saveptr);

  return TRUE;

}

static void reg_load_finish(Reg* reg)

{

  if (!reg)

    return;

  if (reg->buffer)

  {

    free(reg->buffer);

    reg->buffer = NULL;

  }

}

static RegVal* reg_load_value(const Reg* reg, RegKey* key)

{

  const char* p[5] = { 0 };

  size_t length = 0;

  char* name = NULL;

  const char* type = NULL;

  const char* data = NULL;

  RegVal* value = NULL;

  WINPR_ASSERT(reg);

  WINPR_ASSERT(key);

  WINPR_ASSERT(reg->line);

  p[0] = reg->line + 1;

  p[1] = strstr(p[0], "\"=");

  if (!p[1])

    return NULL;

  p[2] = p[1] + 2;

  type = p[2];

  if (p[2][0] == '"')

    p[3] = p[2];

  else

    p[3] = strchr(p[2], ':');

  if (!p[3])

    return NULL;

  data = p[3] + 1;

  length = (size_t)(p[1] - p[0]);

  if (length < 1)

    goto fail;

  name = (char*)calloc(length + 1, sizeof(char));

  if (!name)

    goto fail;

  memcpy(name, p[0], length);

  value = (RegVal*)calloc(1, sizeof(RegVal));

  if (!value)

    goto fail;

  value->name = name;

  value->type = REG_NONE;

  for (size_t index = 0; index < ARRAYSIZE(REG_DATA_TYPE_TABLE); index++)

  {

    const struct reg_data_type* current = &REG_DATA_TYPE_TABLE[index];

    WINPR_ASSERT(current->tag);

    WINPR_ASSERT(current->length > 0);

    WINPR_ASSERT(current->type != REG_NONE);

    if (strncmp(type, current->tag, current->length) == 0)

    {

      value->type = current->type;

      break;

    }

  }

  switch (value->type)

  {

    case REG_DWORD:

    {

      unsigned long val = 0;

      errno = 0;

      val = strtoul(data, NULL, 0);

      if ((errno != 0) || (val > UINT32_MAX))

      {

        WLog_WARN(TAG, "%s::%s value %s invalid", key->name, value->name, data);

        goto fail;

      }

      value->data.dword = (DWORD)val;

    }

    break;

    case REG_QWORD:

    {

      unsigned long long val = 0;

      errno = 0;

      val = strtoull(data, NULL, 0);

      if ((errno != 0) || (val > UINT64_MAX))

      {

        WLog_WARN(TAG, "%s::%s value %s invalid", key->name, value->name, data);

        goto fail;

      }

      value->data.qword = (UINT64)val;

    }

    break;

    case REG_SZ:

    {

      char* start = strchr(data, '"');

      if (!start)

        goto fail;

      /* Check for terminating quote, check it is the last symbol */

      const size_t len = strlen(start);

      char* end = strchr(start + 1, '"');

      if (!end)

        goto fail;

      const intptr_t cmp = end - start + 1;

      if ((cmp < 0) || (len != WINPR_ASSERTING_INT_CAST(size_t, cmp)))

        goto fail;

      if (start[0] == '"')

        start++;

      if (end[0] == '"')

        end[0] = '\0';

      value->data.string = _strdup(start);

      if (!value->data.string)

        goto fail;

    }

    break;

    default:

      WLog_ERR(TAG, "[%s] %s unimplemented format: %s", key->name, value->name,

               reg_data_type_string(value->type));

      break;

  }

  if (!key->values)

  {

    key->values = value;

  }

  else

  {

    RegVal* pValue = key->values;

    while (pValue->next != NULL)

    {

      pValue = pValue->next;

    }

    pValue->next = value;

    value->prev = pValue;

  }

  return value;

fail:

  free(value);

  free(name);

  return NULL;

}

static BOOL reg_load_has_next_line(Reg* reg)

{

  if (!reg)

    return 0;

  return (reg->next_line != NULL) ? 1 : 0;

}

static char* reg_load_get_next_line(Reg* reg)

{

  if (!reg)

    return NULL;

  reg->line = reg->next_line;

  reg->next_line = strtok_s(NULL, "\n", &reg->saveptr);

  reg->line_length = strlen(reg->line);

  return reg->line;

}

static char* reg_load_peek_next_line(Reg* reg)

{

  WINPR_ASSERT(reg);

  return reg->next_line;

}

static void reg_insert_key(WINPR_ATTR_UNUSED Reg* reg, RegKey* key, RegKey* subkey)

{

  char* name = NULL;

  char* path = NULL;

  char* save = NULL;

  WINPR_ASSERT(reg);

  WINPR_ASSERT(key);

  WINPR_ASSERT(subkey);

  WINPR_ASSERT(subkey->name);

  path = _strdup(subkey->name);

  if (!path)

    return;

  name = strtok_s(path, "\\", &save);

  while (name != NULL)

  {

    if (strcmp(key->name, name) == 0)

    {

      if (save)

        subkey->subname = _strdup(save);

      /* TODO: free allocated memory in error case */

      if (!subkey->subname)

      {

        free(path);

        return;

      }

    }

    name = strtok_s(NULL, "\\", &save);

  }

  free(path);

}

static RegKey* reg_load_key(Reg* reg, RegKey* key)

{

  char* p[2];

  size_t length = 0;

  RegKey* subkey = NULL;

  WINPR_ASSERT(reg);

  WINPR_ASSERT(key);

  WINPR_ASSERT(reg->line);

  p[0] = reg->line + 1;

  p[1] = strrchr(p[0], ']');

  if (!p[1])

    return NULL;

  subkey = (RegKey*)calloc(1, sizeof(RegKey));

  if (!subkey)

    return NULL;

  length = (size_t)(p[1] - p[0]);

  subkey->name = (char*)malloc(length + 1);

  if (!subkey->name)

  {

    free(subkey);

    return NULL;

  }

  memcpy(subkey->name, p[0], length);

  subkey->name[length] = '\0';

  while (reg_load_has_next_line(reg))

  {

    char* line = reg_load_peek_next_line(reg);

    if (line[0] == '[')

      break;

    reg_load_get_next_line(reg);

    if (reg->line[0] == '"')

    {

      reg_load_value(reg, subkey);

    }

  }

  reg_insert_key(reg, key, subkey);

  if (!key->subkeys)

  {

    key->subkeys = subkey;

  }

  else

  {

    RegKey* pKey = key->subkeys;

    while (pKey->next != NULL)

    {

      pKey = pKey->next;

    }

    pKey->next = subkey;

    subkey->prev = pKey;

  }

  return subkey;

}

static void reg_load(Reg* reg)

{

  reg_load_start(reg);

  while (reg_load_has_next_line(reg))

  {

    reg_load_get_next_line(reg);

    if (reg->line[0] == '[')

    {

      reg_load_key(reg, reg->root_key);

    }

  }

  reg_load_finish(reg);

}

static void reg_unload_value(WINPR_ATTR_UNUSED Reg* reg, RegVal* value)

{

  WINPR_ASSERT(reg);

  WINPR_ASSERT(value);

  switch (value->type)

  {

    case REG_SZ:

      free(value->data.string);

      break;

    default:

      break;

  }

  free(value);

}

static void reg_unload_key(Reg* reg, RegKey* key)

{

  RegVal* pValue = NULL;

  WINPR_ASSERT(reg);

  WINPR_ASSERT(key);

  pValue = key->values;

  while (pValue != NULL)

  {

    RegVal* pValueNext = pValue->next;

    reg_unload_value(reg, pValue);

    pValue = pValueNext;

  }

  free(key->name);

  free(key);

}

static void reg_unload(Reg* reg)

{

  WINPR_ASSERT(reg);

  if (reg->root_key)

  {

    RegKey* pKey = reg->root_key->subkeys;

    while (pKey != NULL)

    {

      RegKey* pKeyNext = pKey->next;

      reg_unload_key(reg, pKey);

      pKey = pKeyNext;

    }

    free(reg->root_key);

  }

}

Reg* reg_open(BOOL read_only)

{

  Reg* reg = (Reg*)calloc(1, sizeof(Reg));

  if (!reg)

    return NULL;

  reg->read_only = read_only;

  reg->filename = winpr_GetConfigFilePath(TRUE, "HKLM.reg");

  if (!reg->filename)

    goto fail;

  if (reg->read_only)

    reg->fp = winpr_fopen(reg->filename, "r");

  else

  {

    reg->fp = winpr_fopen(reg->filename, "r+");

    if (!reg->fp)

      reg->fp = winpr_fopen(reg->filename, "w+");

  }

  if (!reg->fp)

    goto fail;

  reg->root_key = (RegKey*)calloc(1, sizeof(RegKey));

  if (!reg->root_key)

    goto fail;

  reg->root_key->values = NULL;

  reg->root_key->subkeys = NULL;

  reg->root_key->name = "HKEY_LOCAL_MACHINE";

  reg_load(reg);

  return reg;

fail:

  reg_close(reg);

  return NULL;

}

void reg_close(Reg* reg)

{

  if (reg)

  {

    reg_unload(reg);

    if (reg->fp)

      (void)fclose(reg->fp);

    free(reg->filename);

    free(reg);

  }

}

const char* reg_type_string(DWORD type)

{

  switch (type)

  {

    case REG_NONE:

      return "REG_NONE";

    case REG_SZ:

      return "REG_SZ";

    case REG_EXPAND_SZ:

      return "REG_EXPAND_SZ";

    case REG_BINARY:

      return "REG_BINARY";

    case REG_DWORD:

      return "REG_DWORD";

    case REG_DWORD_BIG_ENDIAN:

      return "REG_DWORD_BIG_ENDIAN";

    case REG_LINK:

      return "REG_LINK";

    case REG_MULTI_SZ:

      return "REG_MULTI_SZ";

    case REG_RESOURCE_LIST:

      return "REG_RESOURCE_LIST";

    case REG_FULL_RESOURCE_DESCRIPTOR:

      return "REG_FULL_RESOURCE_DESCRIPTOR";

    case REG_RESOURCE_REQUIREMENTS_LIST:

      return "REG_RESOURCE_REQUIREMENTS_LIST";

    case REG_QWORD:

      return "REG_QWORD";

    default:

      return "REG_UNKNOWN";

  }

}