/* Feel free to use this example code in any way
you see fit (Public Domain) */
#include <sys/types.h>
#ifndef _WIN32
#include <sys/select.h>
#include <sys/socket.h>
#else
#include <winsock2.h>
#endif
#include <microhttpd.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#define PORT 8888
#define REALM "\"Maintenance\""
#define USER "a legitimate user"
#define PASSWORD "and his password"
#define SERVERKEYFILE "server.key"
#define SERVERCERTFILE "server.pem"
static char *
string_to_base64 (const char *message)
{
const char *lookup =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
unsigned long l;
size_t i;
char *tmp;
size_t length = strlen (message);
tmp = malloc (length * 2);
if (NULL == tmp)
return tmp;
tmp[0] = 0;
for (i = 0; i < length; i += 3)
{
l = (((unsigned long) message[i]) << 16)
| (((i + 1) < length) ? (((unsigned long) message[i + 1]) << 8) : 0)
| (((i + 2) < length) ? ((unsigned long) message[i + 2]) : 0);
strncat (tmp, &lookup[(l >> 18) & 0x3F], 1);
strncat (tmp, &lookup[(l >> 12) & 0x3F], 1);
if (i + 1 < length)
strncat (tmp, &lookup[(l >> 6) & 0x3F], 1);
if (i + 2 < length)
strncat (tmp, &lookup[l & 0x3F], 1);
}
if (length % 3)
strncat (tmp, "===", 3 - length % 3);
return tmp;
}
static long
get_file_size (const char *filename)
{
FILE *fp;
fp = fopen (filename, "rb");
if (fp)
{
long size;
if ((0 != fseek (fp, 0, SEEK_END)) || (-1 == (size = ftell (fp))))
size = 0;
fclose (fp);
return size;
}
else
return 0;
}
static char *
load_file (const char *filename)
{
FILE *fp;
char *buffer;
long size;
size = get_file_size (filename);
if (0 == size)
return NULL;
fp = fopen (filename, "rb");
if (! fp)
return NULL;
buffer = malloc (size + 1);
if (! buffer)
{
fclose (fp);
return NULL;
}
buffer[size] = '\0';
if (size != (long)fread (buffer, 1, size, fp))
{
free (buffer);
buffer = NULL;
}
fclose (fp);
return buffer;
}
static int
ask_for_authentication (struct MHD_Connection *connection, const char *realm)
{
int ret;
struct MHD_Response *response;
char *headervalue;
const char *strbase = "Basic realm=";
response = MHD_create_response_from_buffer (0, NULL,
MHD_RESPMEM_PERSISTENT);
if (!response)
return MHD_NO;
headervalue = malloc (strlen (strbase) + strlen (realm) + 1);
if (!headervalue)
return MHD_NO;
strcpy (headervalue, strbase);
strcat (headervalue, realm);
ret = MHD_add_response_header (response, "WWW-Authenticate", headervalue);
free (headervalue);
if (!ret)
{
MHD_destroy_response (response);
return MHD_NO;
}
ret = MHD_queue_response (connection, MHD_HTTP_UNAUTHORIZED, response);
MHD_destroy_response (response);
return ret;
}
static int
is_authenticated (struct MHD_Connection *connection,
const char *username, const char *password)
{
const char *headervalue;
char *expected_b64, *expected;
const char *strbase = "Basic ";
int authenticated;
headervalue =
MHD_lookup_connection_value (connection, MHD_HEADER_KIND,
"Authorization");
if (NULL == headervalue)
return 0;
if (0 != strncmp (headervalue, strbase, strlen (strbase)))
return 0;
expected = malloc (strlen (username) + 1 + strlen (password) + 1);
if (NULL == expected)
return 0;
strcpy (expected, username);
strcat (expected, ":");
strcat (expected, password);
expected_b64 = string_to_base64 (expected);
free (expected);
if (NULL == expected_b64)
return 0;
authenticated =
(strcmp (headervalue + strlen (strbase), expected_b64) == 0);
free (expected_b64);
return authenticated;
}
static int
secret_page (struct MHD_Connection *connection)
{
int ret;
struct MHD_Response *response;
const char *page = "<html><body>A secret.</body></html>";
response =
MHD_create_response_from_buffer (strlen (page), (void *) page,
MHD_RESPMEM_PERSISTENT);
if (!response)
return MHD_NO;
ret = MHD_queue_response (connection, MHD_HTTP_OK, response);
MHD_destroy_response (response);
return ret;
}
static int
answer_to_connection (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 **con_cls)
{
(void)cls; /* Unused. Silent compiler warning. */
(void)url; /* 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, "GET"))
return MHD_NO;
if (NULL == *con_cls)
{
*con_cls = connection;
return MHD_YES;
}
if (!is_authenticated (connection, USER, PASSWORD))
return ask_for_authentication (connection, REALM);
return secret_page (connection);
}
int
main ()
{
struct MHD_Daemon *daemon;
char *key_pem;
char *cert_pem;
key_pem = load_file (SERVERKEYFILE);
cert_pem = load_file (SERVERCERTFILE);
if ((key_pem == NULL) || (cert_pem == NULL))
{
printf ("The key/certificate files could not be read.\n");
if (NULL != key_pem)
free (key_pem);
if (NULL != cert_pem)
free (cert_pem);
return 1;
}
daemon =
MHD_start_daemon (MHD_USE_INTERNAL_POLLING_THREAD | MHD_USE_TLS, PORT, NULL,
NULL, &answer_to_connection, NULL,
MHD_OPTION_HTTPS_MEM_KEY, key_pem,
MHD_OPTION_HTTPS_MEM_CERT, cert_pem, MHD_OPTION_END);
if (NULL == daemon)
{
printf ("%s\n", cert_pem);
free (key_pem);
free (cert_pem);
return 1;
}
(void) getchar ();
MHD_stop_daemon (daemon);
free (key_pem);
free (cert_pem);
return 0;
}