registry_reg.c

 
#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";
  }
}