/**

 * FreeRDP: A Remote Desktop Protocol Implementation

 * Passphrase Handling Utils

 *

 * Copyright 2011 Shea Levy <shea@shealevy.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/atexit.h>

#include <winpr/environment.h>

#include <freerdp/config.h>

#include <freerdp/freerdp.h>

#include <errno.h>

#include <freerdp/utils/passphrase.h>

#ifdef _WIN32

#include <stdio.h>

#include <string.h>

#include <io.h>

#include <conio.h>

#include <wincred.h>

static char read_chr(FILE* f)

{

  char chr;

  const BOOL isTty = _isatty(_fileno(f));

  if (isTty)

    return fgetc(f);

  if (fscanf_s(f, "%c", &chr, (UINT32)sizeof(char)) && !feof(f))

    return chr;

  return 0;

}

int freerdp_interruptible_getc(rdpContext* context, FILE* f)

{

  return read_chr(f);

}

const char* freerdp_passphrase_read(rdpContext* context, const char* prompt, char* buf,

                                    size_t bufsiz, int from_stdin)

{

  if (bufsiz == 0)

  {

    errno = EINVAL;

    return nullptr;

  }

  /* When /from-stdin is requested, read the password from stdin. The Unix

   * counterpart (freerdp_passphrase_read_tty) does the same, suppressing

   * terminal echo via tcsetattr; suppress console echo here via SetConsoleMode

   * when stdin is an interactive console. On a pipe the echo bit is moot. */

  if (from_stdin)

  {

    HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);

    const BOOL isTty = _isatty(_fileno(stdin)) != 0;

    DWORD origMode = 0;

    BOOL echoSuppressed = FALSE;

    if (isTty && hStdin && hStdin != INVALID_HANDLE_VALUE && GetConsoleMode(hStdin, &origMode))

    {

      if (SetConsoleMode(hStdin, origMode & ~(DWORD)ENABLE_ECHO_INPUT))

        echoSuppressed = TRUE;

    }

    if (prompt)

    {

      (void)fputs(prompt, stdout);

      (void)fflush(stdout);

    }

    WINPR_ASSERT(bufsiz <= INT32_MAX);

    const char* rc = fgets(buf, (int)bufsiz, stdin);

    if (echoSuppressed)

    {

      (void)SetConsoleMode(hStdin, origMode);

      (void)fputc('\n', stdout);

      (void)fflush(stdout);

    }

    if (!rc)

      return nullptr;

    buf[strcspn(buf, "\r\n")] = '\0';

    return buf;

  }

  WCHAR UserNameW[CREDUI_MAX_USERNAME_LENGTH + 1] = { 'p', 'r', 'e', 'f', 'i',

                                                    'l', 'l', 'e', 'd', '\0' };

  WCHAR PasswordW[CREDUI_MAX_PASSWORD_LENGTH + 1] = WINPR_C_ARRAY_INIT;

  BOOL fSave = FALSE;

  DWORD dwFlags = 0;

  WCHAR* promptW = ConvertUtf8ToWCharAlloc(prompt, nullptr);

  const DWORD status =

      CredUICmdLinePromptForCredentialsW(promptW, nullptr, 0, UserNameW, ARRAYSIZE(UserNameW),

                                         PasswordW, ARRAYSIZE(PasswordW), &fSave, dwFlags);

  free(promptW);

  if (ConvertWCharNToUtf8(PasswordW, ARRAYSIZE(PasswordW), buf, bufsiz) < 0)

    return nullptr;

  return buf;

}

const char* freerdp_passphrase_from_env(WINPR_ATTR_UNUSED rdpContext* context,

                                        WINPR_ATTR_UNUSED const char* prompt,

                                        WINPR_ATTR_UNUSED char* buf,

                                        WINPR_ATTR_UNUSED size_t bufsiz)

{

  return nullptr;

}

const char* freerdp_passphrase_read_tty(WINPR_ATTR_UNUSED rdpContext* context,

                                        WINPR_ATTR_UNUSED const char* prompt,

                                        WINPR_ATTR_UNUSED char* buf,

                                        WINPR_ATTR_UNUSED size_t bufsiz,

                                        WINPR_ATTR_UNUSED int from_stdin)

{

  return nullptr;

}

#elif !defined(ANDROID)

#include <fcntl.h>

#include <stdio.h>

#include <string.h>

#include <sys/stat.h>

#include <sys/wait.h>

#include <termios.h>

#include <unistd.h>

#include <freerdp/utils/signal.h>

#include <freerdp/log.h>

#if defined(WINPR_HAVE_POLL_H) && !defined(__APPLE__)

#include <poll.h>

#else

#include <time.h>

#include <sys/select.h>

#endif

#define TAG FREERDP_TAG("utils.passphrase")

static int wait_for_fd(int fd, int timeout)

{

  int status = 0;

#if defined(WINPR_HAVE_POLL_H) && !defined(__APPLE__)

  struct pollfd pollset = WINPR_C_ARRAY_INIT;

  pollset.fd = fd;

  pollset.events = POLLIN;

  pollset.revents = 0;

  do

  {

    status = poll(&pollset, 1, timeout);

  } while ((status < 0) && (errno == EINTR));

#else

  fd_set rset = WINPR_C_ARRAY_INIT;

  struct timeval tv = WINPR_C_ARRAY_INIT;

  FD_ZERO(&rset);

  FD_SET(fd, &rset);

  if (timeout)

  {

    tv.tv_sec = timeout / 1000;

    tv.tv_usec = (timeout % 1000) * 1000;

  }

  do

  {

    status = select(fd + 1, &rset, nullptr, nullptr, timeout ? &tv : nullptr);

  } while ((status < 0) && (errno == EINTR));

#endif

  return status;

}

static void replace_char(char* buffer, WINPR_ATTR_UNUSED size_t buffer_len, const char* toreplace)

{

  while (*toreplace != '\0')

  {

    char* ptr = nullptr;

    while ((ptr = strrchr(buffer, *toreplace)) != nullptr)

      *ptr = '\0';

    toreplace++;

  }

}

const char* freerdp_passphrase_read_tty(rdpContext* context, const char* prompt, char* buf,

                                        size_t bufsiz, int from_stdin)

{

  BOOL terminal_needs_reset = FALSE;

  char term_name[L_ctermid] = WINPR_C_ARRAY_INIT;

  FILE* fout = nullptr;

  if (bufsiz == 0)

  {

    errno = EINVAL;

    return nullptr;

  }

  ctermid(term_name);

  int terminal_fildes = 0;

  if (from_stdin || (strcmp(term_name, "") == 0))

  {

    fout = stdout;

    terminal_fildes = STDIN_FILENO;

  }

  else

  {

    const int term_file = open(term_name, O_RDWR);

    if (term_file < 0)

    {

      fout = stdout;

      terminal_fildes = STDIN_FILENO;

    }

    else

    {

      fout = fdopen(term_file, "w");

      if (!fout)

      {

        close(term_file);

        return nullptr;

      }

      terminal_fildes = term_file;

    }

  }

  struct termios orig_flags = WINPR_C_ARRAY_INIT;

  if (tcgetattr(terminal_fildes, &orig_flags) != -1)

  {

    struct termios new_flags = WINPR_C_ARRAY_INIT;

    new_flags = orig_flags;

    new_flags.c_lflag &= (uint32_t)~ECHO;

    new_flags.c_lflag |= ECHONL;

    terminal_needs_reset = TRUE;

    if (tcsetattr(terminal_fildes, TCSAFLUSH, &new_flags) == -1)

      terminal_needs_reset = FALSE;

  }

  FILE* fp = fdopen(terminal_fildes, "r");

  if (!fp)

    goto error;

  (void)fprintf(fout, "%s", prompt);

  (void)fflush(fout);

  {

    char* ptr = nullptr;

    size_t ptr_len = 0;

    const SSIZE_T res = freerdp_interruptible_get_line(context, &ptr, &ptr_len, fp);

    if (res < 0)

      goto error;

    replace_char(ptr, ptr_len, "\r\n");

    strncpy(buf, ptr, MIN(bufsiz, ptr_len));

    free(ptr);

  }

  if (terminal_needs_reset)

  {

    if (tcsetattr(terminal_fildes, TCSAFLUSH, &orig_flags) == -1)

      goto error;

  }

  if (terminal_fildes != STDIN_FILENO)

    (void)fclose(fp);

  return buf;

error:

{

  // NOLINTNEXTLINE(clang-analyzer-unix.Stream)

  int saved_errno = errno;

  if (terminal_needs_reset)

    (void)tcsetattr(terminal_fildes, TCSAFLUSH, &orig_flags);

  if (terminal_fildes != STDIN_FILENO)

  {

    if (fp)

      (void)fclose(fp);

  }

  // NOLINTNEXTLINE(clang-analyzer-unix.Stream)

  errno = saved_errno;

}

  return nullptr;

}

static const char* freerdp_passphrase_read_askpass(const char* prompt, char* buf, size_t bufsiz,

                                                   char const* askpass_env)

{

  char command[4096] = WINPR_C_ARRAY_INIT;

  (void)sprintf_s(command, sizeof(command), "%s 'FreeRDP authentication\n%s'", askpass_env,

                  prompt);

  // NOLINTNEXTLINE(clang-analyzer-optin.taint.GenericTaint,bugprone-command-processor)

  FILE* askproc = popen(command, "r");

  if (!askproc)

    return nullptr;

  WINPR_ASSERT(bufsiz <= INT32_MAX);

  if (fgets(buf, (int)bufsiz, askproc) != nullptr)

    buf[strcspn(buf, "\r\n")] = '\0';

  else

    buf = nullptr;

  const int status = pclose(askproc);

  if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)

    buf = nullptr;

  return buf;

}

const char* freerdp_passphrase_from_env(WINPR_ATTR_UNUSED rdpContext* context, const char* prompt,

                                        char* buf, size_t bufsiz)

{

  // NOLINTNEXTLINE(concurrency-mt-unsafe)

  const char* askpass_env = getenv("FREERDP_ASKPASS");

  if (!askpass_env)

    return nullptr;

  return freerdp_passphrase_read_askpass(prompt, buf, bufsiz, askpass_env);

}

const char* freerdp_passphrase_read(rdpContext* context, const char* prompt, char* buf,

                                    size_t bufsiz, int from_stdin)

{

  const char* askpass_env = freerdp_passphrase_from_env(context, prompt, buf, bufsiz);

  if (askpass_env)

    return askpass_env;

  return freerdp_passphrase_read_tty(context, prompt, buf, bufsiz, from_stdin);

}

static BOOL set_termianl_nonblock(int ifd, BOOL nonblock);

static void restore_terminal(void)

{

  (void)set_termianl_nonblock(-1, FALSE);

}

BOOL set_termianl_nonblock(int ifd, BOOL nonblock)

{

  static int fd = -1;

  static bool registered = false;

  static int orig = 0;

  static struct termios termios = WINPR_C_ARRAY_INIT;

  if (ifd >= 0)

    fd = ifd;

  if (fd < 0)

    return FALSE;

  if (nonblock)

  {

    if (!registered)

    {

      (void)winpr_atexit(restore_terminal);

      registered = true;

    }

    const int rc1 = fcntl(fd, F_SETFL, orig | O_NONBLOCK);

    if (rc1 != 0)

    {

      char buffer[128] = WINPR_C_ARRAY_INIT;

      WLog_ERR(TAG, "fcntl(F_SETFL) failed with %s",

               winpr_strerror(errno, buffer, sizeof(buffer)));

      return FALSE;

    }

    const int rc2 = tcgetattr(fd, &termios);

    if (rc2 != 0)

    {

      char buffer[128] = WINPR_C_ARRAY_INIT;

      WLog_ERR(TAG, "tcgetattr() failed with %s",

               winpr_strerror(errno, buffer, sizeof(buffer)));

      return FALSE;

    }

    struct termios now = termios;

    cfmakeraw(&now);

    const int rc3 = tcsetattr(fd, TCSANOW, &now);

    if (rc3 != 0)

    {

      char buffer[128] = WINPR_C_ARRAY_INIT;

      WLog_ERR(TAG, "tcsetattr(TCSANOW) failed with %s",

               winpr_strerror(errno, buffer, sizeof(buffer)));

      return FALSE;

    }

  }

  else

  {

    const int rc1 = tcsetattr(fd, TCSANOW, &termios);

    if (rc1 != 0)

    {

      char buffer[128] = WINPR_C_ARRAY_INIT;

      WLog_ERR(TAG, "tcsetattr(TCSANOW) failed with %s",

               winpr_strerror(errno, buffer, sizeof(buffer)));

      return FALSE;

    }

    const int rc2 = fcntl(fd, F_SETFL, orig);

    if (rc2 != 0)

    {

      char buffer[128] = WINPR_C_ARRAY_INIT;

      WLog_ERR(TAG, "fcntl(F_SETFL) failed with %s",

               winpr_strerror(errno, buffer, sizeof(buffer)));

      return FALSE;

    }

    fd = -1;

  }

  return TRUE;

}

int freerdp_interruptible_getc(rdpContext* context, FILE* stream)

{

  int rc = EOF;

  const int fd = fileno(stream);

  (void)set_termianl_nonblock(fd, TRUE);

  do

  {

    const int res = wait_for_fd(fd, 10);

    if (res != 0)

    {

      char c = 0;

      const ssize_t rd = read(fd, &c, 1);

      if (rd == 1)

      {

        if (c == 3) /* ctrl + c */

          return EOF;

        if (c == 4) /* ctrl + d */

          return EOF;

        if (c == 26) /* ctrl + z */

          return EOF;

        rc = (int)c;

      }

      break;

    }

  } while (!freerdp_shall_disconnect_context(context));

  (void)set_termianl_nonblock(fd, FALSE);

  return rc;

}

#else

const char* freerdp_passphrase_read(rdpContext* context, const char* prompt, char* buf,

                                    size_t bufsiz, int from_stdin)

{

  return nullptr;

}

int freerdp_interruptible_getc(rdpContext* context, FILE* f)

{

  return EOF;

}

const char* freerdp_passphrase_from_env(WINPR_ATTR_UNUSED rdpContext* context,

                                        WINPR_ATTR_UNUSED const char* prompt,

                                        WINPR_ATTR_UNUSED char* buf,

                                        WINPR_ATTR_UNUSED size_t bufsiz)

{

  return nullptr;

}

const char* freerdp_passphrase_read_tty(WINPR_ATTR_UNUSED rdpContext* context,

                                        WINPR_ATTR_UNUSED const char* prompt,

                                        WINPR_ATTR_UNUSED char* buf,

                                        WINPR_ATTR_UNUSED size_t bufsiz,

                                        WINPR_ATTR_UNUSED int from_stdin)

{

  return nullptr;

}

#endif

SSIZE_T freerdp_interruptible_get_line(rdpContext* context, char** plineptr, size_t* psize,

                                       FILE* stream)

{

  int c = 0;

  char* n = nullptr;

  size_t step = 32;

  size_t used = 0;

  char* ptr = nullptr;

  size_t len = 0;

  if (!plineptr || !psize)

  {

    errno = EINVAL;

    return -1;

  }

  bool echo = true;

#if !defined(_WIN32) && !defined(ANDROID)

  {

    const int fd = fileno(stream);

    struct termios termios = WINPR_C_ARRAY_INIT;

    /* This might fail if /from-stdin is used. */

    if (tcgetattr(fd, &termios) == 0)

      echo = (termios.c_lflag & ECHO) != 0;

    else

      echo = false;

  }

#endif

  if (*plineptr && (*psize > 0))

  {

    ptr = *plineptr;

    used = *psize;

    if (echo)

    {

      printf("%s", ptr);

      (void)fflush(stdout);

    }

  }

  do

  {

    if (used + 2 >= len)

    {

      len += step;

      n = realloc(ptr, len);

      if (!n)

      {

        free(ptr);

        *plineptr = nullptr;

        return -1;

      }

      ptr = n;

    }

    c = freerdp_interruptible_getc(context, stream);

    if (c == 127)

    {

      if (used > 0)

      {

        ptr[used--] = '\0';

        if (echo)

        {

          printf("\b");

          printf(" ");

          printf("\b");

          (void)fflush(stdout);

        }

      }

      continue;

    }

    if (echo)

    {

      printf("%c", c);

      (void)fflush(stdout);

    }

    if (c != EOF)

      ptr[used++] = (char)c;

  } while ((c != '\n') && (c != '\r') && (c != EOF));

  printf("\n");

  ptr[used] = '\0';

  if (c == EOF)

  {

    free(ptr);

    *plineptr = nullptr;

    return EOF;

  }

  *plineptr = ptr;

  *psize = used;

  return WINPR_ASSERTING_INT_CAST(SSIZE_T, used);

}