/*
     This file is part of libmicrohttpd
     Copyright (C) 2007, 2008 Christian Grothoff (and other contributing authors)

     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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/
/**
 * @file https_fileserver_example.c
 * @brief a simple HTTPS file server using TLS.
 *
 * Usage :
 *
 *  'http_fileserver_example HTTP-PORT SECONDS-TO-RUN'
 *
 * The certificate & key are required by the server to operate, omitting the
 * path arguments will cause the server to use the hard coded example certificate & key.
 *
 * 'certtool' may be used to generate these if required.
 *
 * @author Sagie Amir
 */

#include "platform.h"
#include <microhttpd.h>
#include <sys/stat.h>

#define BUF_SIZE 1024
#define MAX_URL_LEN 255

/* TODO remove if unused */
#define CAFILE "ca.pem"
#define CRLFILE "crl.pem"

#define EMPTY_PAGE "<html><head><title>File not found</title></head><body>File not found</body></html>"

/* Test Certificate */
const char cert_pem[] =
  "-----BEGIN CERTIFICATE-----\n"
  "MIICpjCCAZCgAwIBAgIESEPtjjALBgkqhkiG9w0BAQUwADAeFw0wODA2MDIxMjU0\n"
  "MzhaFw0wOTA2MDIxMjU0NDZaMAAwggEfMAsGCSqGSIb3DQEBAQOCAQ4AMIIBCQKC\n"
  "AQC03TyUvK5HmUAirRp067taIEO4bibh5nqolUoUdo/LeblMQV+qnrv/RNAMTx5X\n"
  "fNLZ45/kbM9geF8qY0vsPyQvP4jumzK0LOJYuIwmHaUm9vbXnYieILiwCuTgjaud\n"
  "3VkZDoQ9fteIo+6we9UTpVqZpxpbLulBMh/VsvX0cPJ1VFC7rT59o9hAUlFf9jX/\n"
  "GmKdYI79MtgVx0OPBjmmSD6kicBBfmfgkO7bIGwlRtsIyMznxbHu6VuoX/eVxrTv\n"
  "rmCwgEXLWRZ6ru8MQl5YfqeGXXRVwMeXU961KefbuvmEPccgCxm8FZ1C1cnDHFXh\n"
  "siSgAzMBjC/b6KVhNQ4KnUdZAgMBAAGjLzAtMAwGA1UdEwEB/wQCMAAwHQYDVR0O\n"
  "BBYEFJcUvpjvE5fF/yzUshkWDpdYiQh/MAsGCSqGSIb3DQEBBQOCAQEARP7eKSB2\n"
  "RNd6XjEjK0SrxtoTnxS3nw9sfcS7/qD1+XHdObtDFqGNSjGYFB3Gpx8fpQhCXdoN\n"
  "8QUs3/5ZVa5yjZMQewWBgz8kNbnbH40F2y81MHITxxCe1Y+qqHWwVaYLsiOTqj2/\n"
  "0S3QjEJ9tvklmg7JX09HC4m5QRYfWBeQLD1u8ZjA1Sf1xJriomFVyRLI2VPO2bNe\n"
  "JDMXWuP+8kMC7gEvUnJ7A92Y2yrhu3QI3bjPk8uSpHea19Q77tul1UVBJ5g+zpH3\n"
  "OsF5p0MyaVf09GTzcLds5nE/osTdXGUyHJapWReVmPm3Zn6gqYlnzD99z+DPIgIV\n"
  "RhZvQx74NQnS6g==\n" "-----END CERTIFICATE-----\n";

const char key_pem[] =
  "-----BEGIN RSA PRIVATE KEY-----\n"
  "MIIEowIBAAKCAQEAtN08lLyuR5lAIq0adOu7WiBDuG4m4eZ6qJVKFHaPy3m5TEFf\n"
  "qp67/0TQDE8eV3zS2eOf5GzPYHhfKmNL7D8kLz+I7psytCziWLiMJh2lJvb2152I\n"
  "niC4sArk4I2rnd1ZGQ6EPX7XiKPusHvVE6VamacaWy7pQTIf1bL19HDydVRQu60+\n"
  "faPYQFJRX/Y1/xpinWCO/TLYFcdDjwY5pkg+pInAQX5n4JDu2yBsJUbbCMjM58Wx\n"
  "7ulbqF/3lca0765gsIBFy1kWeq7vDEJeWH6nhl10VcDHl1PetSnn27r5hD3HIAsZ\n"
  "vBWdQtXJwxxV4bIkoAMzAYwv2+ilYTUOCp1HWQIDAQABAoIBAArOQv3R7gmqDspj\n"
  "lDaTFOz0C4e70QfjGMX0sWnakYnDGn6DU19iv3GnX1S072ejtgc9kcJ4e8VUO79R\n"
  "EmqpdRR7k8dJr3RTUCyjzf/C+qiCzcmhCFYGN3KRHA6MeEnkvRuBogX4i5EG1k5l\n"
  "/5t+YBTZBnqXKWlzQLKoUAiMLPg0eRWh+6q7H4N7kdWWBmTpako7TEqpIwuEnPGx\n"
  "u3EPuTR+LN6lF55WBePbCHccUHUQaXuav18NuDkcJmCiMArK9SKb+h0RqLD6oMI/\n"
  "dKD6n8cZXeMBkK+C8U/K0sN2hFHACsu30b9XfdnljgP9v+BP8GhnB0nCB6tNBCPo\n"
  "32srOwECgYEAxWh3iBT4lWqL6bZavVbnhmvtif4nHv2t2/hOs/CAq8iLAw0oWGZc\n"
  "+JEZTUDMvFRlulr0kcaWra+4fN3OmJnjeuFXZq52lfMgXBIKBmoSaZpIh2aDY1Rd\n"
  "RbEse7nQl9hTEPmYspiXLGtnAXW7HuWqVfFFP3ya8rUS3t4d07Hig8ECgYEA6ou6\n"
  "OHiBRTbtDqLIv8NghARc/AqwNWgEc9PelCPe5bdCOLBEyFjqKiT2MttnSSUc2Zob\n"
  "XhYkHC6zN1Mlq30N0e3Q61YK9LxMdU1vsluXxNq2rfK1Scb1oOlOOtlbV3zA3VRF\n"
  "hV3t1nOA9tFmUrwZi0CUMWJE/zbPAyhwWotKyZkCgYEAh0kFicPdbABdrCglXVae\n"
  "SnfSjVwYkVuGd5Ze0WADvjYsVkYBHTvhgRNnRJMg+/vWz3Sf4Ps4rgUbqK8Vc20b\n"
  "AU5G6H6tlCvPRGm0ZxrwTWDHTcuKRVs+pJE8C/qWoklE/AAhjluWVoGwUMbPGuiH\n"
  "6Gf1bgHF6oj/Sq7rv/VLZ8ECgYBeq7ml05YyLuJutuwa4yzQ/MXfghzv4aVyb0F3\n"
  "QCdXR6o2IYgR6jnSewrZKlA9aPqFJrwHNR6sNXlnSmt5Fcf/RWO/qgJQGLUv3+rG\n"
  "7kuLTNDR05azSdiZc7J89ID3Bkb+z2YkV+6JUiPq/Ei1+nDBEXb/m+/HqALU/nyj\n"
  "P3gXeQKBgBusb8Rbd+KgxSA0hwY6aoRTPRt8LNvXdsB9vRcKKHUFQvxUWiUSS+L9\n"
  "/Qu1sJbrUquKOHqksV5wCnWnAKyJNJlhHuBToqQTgKXjuNmVdYSe631saiI7PHyC\n"
  "eRJ6DxULPxABytJrYCRrNqmXi5TCiqR2mtfalEMOPxz8rUU8dYyx\n"
  "-----END RSA PRIVATE KEY-----\n";

static ssize_t
file_reader (void *cls, uint64_t pos, char *buf, size_t max)
{
  FILE *file = cls;

  (void) fseek (file, pos, SEEK_SET);
  return fread (buf, 1, max, file);
}

static void
file_free_callback (void *cls)
{
  FILE *file = cls;
  fclose (file);
}

/* HTTP access handler call back */
static int
http_ahc (void *cls,
          struct MHD_Connection *connection,
          const char *url,
          const char *method,
          const char *version,
          const char *upload_data,
	  size_t *upload_data_size, void **ptr)
{
  static int aptr;
  struct MHD_Response *response;
  int ret;
  FILE *file;
  int fd;
  struct stat buf;
  (void)cls;               /* Unused. Silent compiler warning. */
  (void)version;           /* Unused. Silent compiler warning. */
  (void)upload_data;       /* Unused. Silent compiler warning. */
  (void)upload_data_size;  /* Unused. Silent compiler warning. */

  if (0 != strcmp (method, MHD_HTTP_METHOD_GET))
    return MHD_NO;              /* unexpected method */
  if (&aptr != *ptr)
    {
      /* do never respond on first call */
      *ptr = &aptr;
      return MHD_YES;
    }
  *ptr = NULL;                  /* reset when done */

  file = fopen (&url[1], "rb");
  if (NULL != file)
    {
      fd = fileno (file);
      if (-1 == fd)
        {
          (void) fclose (file);
          return MHD_NO; /* internal error */
        }
      if ( (0 != fstat (fd, &buf)) ||
           (! S_ISREG (buf.st_mode)) )
        {
          /* not a regular file, refuse to serve */
          fclose (file);
          file = NULL;
        }
    }

  if (NULL == file)
    {
      response = MHD_create_response_from_buffer (strlen (EMPTY_PAGE),
						  (void *) EMPTY_PAGE,
						  MHD_RESPMEM_PERSISTENT);
      ret = MHD_queue_response (connection, MHD_HTTP_NOT_FOUND, response);
      MHD_destroy_response (response);
    }
  else
    {
      response = MHD_create_response_from_callback (buf.st_size, 32 * 1024,     /* 32k PAGE_NOT_FOUND size */
                                                    &file_reader, file,
                                                    &file_free_callback);
      if (NULL == response)
	{
	  fclose (file);
	  return MHD_NO;
	}
      ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
      MHD_destroy_response (response);
    }
  return ret;
}


int
main (int argc, char *const *argv)
{
  struct MHD_Daemon *TLS_daemon;
  int port;

  if (argc != 2)
    {
      printf ("%s PORT\n", argv[0]);
      return 1;
    }
  port = atoi (argv[1]);
  if ( (1 > port) ||
       (port > UINT16_MAX) )
    {
      fprintf (stderr,
               "Port must be a number between 1 and 65535\n");
      return 1;
    }

  TLS_daemon =
    MHD_start_daemon (MHD_USE_THREAD_PER_CONNECTION | MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_ERROR_LOG |
                      MHD_USE_TLS,
                      (uint16_t) port,
                      NULL, NULL,
                      &http_ahc, NULL,
                      MHD_OPTION_CONNECTION_TIMEOUT, 256,
                      MHD_OPTION_HTTPS_MEM_KEY, key_pem,
                      MHD_OPTION_HTTPS_MEM_CERT, cert_pem,
                      MHD_OPTION_END);
  if (NULL == TLS_daemon)
    {
      fprintf (stderr, "Error: failed to start TLS_daemon\n");
      return 1;
    }
  printf ("MHD daemon listening on port %u\n",
          (unsigned int) port);

  (void) getc (stdin);

  MHD_stop_daemon (TLS_daemon);
  return 0;
}
