/*

 * Dropbear SSH

 * 

 * Copyright (c) 2005 Matt Johnston

 * All rights reserved.

 * 

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 * 

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

 * SOFTWARE. */

#include "includes.h"

#include "buffer.h"

#include "dbutil.h"

#include "session.h"

#include "ssh.h"

#include "runopts.h"

#if DROPBEAR_CLI_INTERACT_AUTH

static char* get_response(char* prompt)

{

  FILE* tty = NULL;

  char* response = NULL;

  /* not a password, but a reasonable limit */

  char buf[DROPBEAR_MAX_CLI_PASS];

  char* ret = NULL;

  fprintf(stderr, "%s", prompt);

  tty = fopen(_PATH_TTY, "r");

  if (tty) {

    ret = fgets(buf, sizeof(buf), tty);

    fclose(tty);

  } else {

    ret = fgets(buf, sizeof(buf), stdin);

  }

  if (ret == NULL) {

    response = m_strdup("");

  } else {

    unsigned int buflen = strlen(buf);

    /* fgets includes newlines */

    if (buflen > 0 && buf[buflen-1] == '\n')

      buf[buflen-1] = '\0';

    response = m_strdup(buf);

  }

  m_burn(buf, sizeof(buf));

  return response;

}

void recv_msg_userauth_info_request() {

  char *name = NULL;

  char *instruction = NULL;

  unsigned int num_prompts = 0;

  unsigned int i;

  char *prompt = NULL;

  unsigned int echo = 0;

  char *response = NULL;

  TRACE(("enter recv_msg_recv_userauth_info_request"))

  /* Let the user know what password/host they are authing for */

  if (!cli_ses.interact_request_received) {

    fprintf(stderr, "Login for %s@%s\n", cli_opts.username,

        cli_opts.remotehost);

  }

  cli_ses.interact_request_received = 1;

  name = buf_getstring(ses.payload, NULL);

  instruction = buf_getstring(ses.payload, NULL);

  /* language tag */

  buf_eatstring(ses.payload);

  num_prompts = buf_getint(ses.payload);

  if (num_prompts >= DROPBEAR_MAX_CLI_INTERACT_PROMPTS) {

    dropbear_exit("Too many prompts received for keyboard-interactive");

  }

  /* we'll build the response as we go */

  CHECKCLEARTOWRITE();

  buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_INFO_RESPONSE);

  buf_putint(ses.writepayload, num_prompts);

  if (strlen(name) > 0) {

    cleantext(name);

    fprintf(stderr, "%s", name);

  }

  m_free(name);

  if (strlen(instruction) > 0) {

    cleantext(instruction);

    fprintf(stderr, "%s", instruction);

  }

  m_free(instruction);

  for (i = 0; i < num_prompts; i++) {

    unsigned int response_len = 0;

    cli_ses.is_trivial_auth = 0;

    prompt = buf_getstring(ses.payload, NULL);

    cleantext(prompt);

    echo = buf_getbool(ses.payload);

    if (!echo) {

      char* p = getpass_or_cancel(prompt);

      response = m_strdup(p);

      m_burn(p, strlen(p));

    } else {

      response = get_response(prompt);

    }

    response_len = strlen(response);

    buf_putstring(ses.writepayload, response, response_len);

    m_burn(response, response_len);

    m_free(prompt);

    m_free(response);

  }

  encrypt_packet();

  TRACE(("leave recv_msg_recv_userauth_info_request"))

}

void cli_auth_interactive() {

  TRACE(("enter cli_auth_interactive"))

  CHECKCLEARTOWRITE();

  buf_putbyte(ses.writepayload, SSH_MSG_USERAUTH_REQUEST);

  /* username */

  buf_putstring(ses.writepayload, cli_opts.username,

      strlen(cli_opts.username));

  /* service name */

  buf_putstring(ses.writepayload, SSH_SERVICE_CONNECTION,

      SSH_SERVICE_CONNECTION_LEN);

  /* method */

  buf_putstring(ses.writepayload, AUTH_METHOD_INTERACT,

      AUTH_METHOD_INTERACT_LEN);

  /* empty language tag */

  buf_putstring(ses.writepayload, "", 0);

  /* empty submethods */

  buf_putstring(ses.writepayload, "", 0);

  encrypt_packet();

  cli_ses.interact_request_received = 0;

  TRACE(("leave cli_auth_interactive"))

}

#endif  /* DROPBEAR_CLI_INTERACT_AUTH */