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|
/*
This file is part of libmicrohttpd
Copyright (C) 2010 Christian Grothoff (and other contributing authors)
Copyright (C) 2016-2024 Evgeny Grin (Karlson2k)
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 digest_auth_example_adv.c
* @brief Advanced example for digest auth with libmicrohttpd
* @author Karlson2k (Evgeny Grin)
*/
#include <microhttpd.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#if ! defined(_WIN32) || defined(__CYGWIN__)
# include <errno.h>
# include <fcntl.h>
# include <unistd.h>
#else /* Native W32 */
# include <wincrypt.h>
#endif /* Native W32 */
#define SEC_AREA1_URL "/secret_page/"
#define SEC_AREA2_URL "/super_secret_page/"
#define MAIN_PAGE \
"<html><head><title>Welcome to the site</title></head>" \
"<body><p><a href=\"" SEC_AREA1_URL "\">Restricted Page</a></p>" \
"<p><a href=\"" SEC_AREA2_URL "\">Very Restricted Page</a></p></body></html>"
#define OPAQUE_DATA "ServerOpaqueData"
#define REALM "authenticated_users@thishost"
/**
* Force select "MD5" algorithm instead of MHD default (currently the same) if non-zero.
*/
static int force_md5 = 0;
/**
* Force select "SHA-256" algorithm instead of MHD default (MD5) if non-zero.
*/
static int force_sha256 = 0;
/**
* Force select "SHA-512/256" algorithm instead of MHD default (MD5) if non-zero.
*/
static int force_sha512_256 = 0;
/**
* Disable fallback to (less secure) RFC2069 if non-zero.
*/
static int allow_rfc2069 = 0;
/**
* The daemon's port
*/
static uint16_t daemon_port = 0;
/* *** "Database" of users and "database" functions *** */
/**
* User record.
* This kind of data (or something similar) should be stored in some database
* or file.
*/
struct UserEntry
{
/**
* The username.
* Static data is used in this example.
* In real application dynamic buffer or fixed size array could be used.
*/
const char *username;
#if 0 /* Disabled code */
/* The cleartext password is not stored in the database.
The more secure "userdigest" is used instead. */
/**
* The password.
* Static data is used in this example.
* In real application dynamic buffer or fixed size array could be used.
*/
const char *password;
#endif /* Disabled code */
/**
* The realm for this entry.
* Static data is used in this example.
* In real application dynamic buffer or fixed size array could be used.
*/
const char *realm;
/**
* The MD5 hash of the username together with the realm.
* This hash can be used by the client to send the username in encrypted
* form.
* The purpose of userhash is to hide user identity when transmitting
* requests over insecure link.
*/
uint8_t userhash_md5[MHD_MD5_DIGEST_SIZE];
/**
* The MD5 hash of the username with the password and the realm.
* It is used to verify that password used by the client matches password
* required by the server.
* The purpose of userhash is to avoid keeping the password in cleartext
* on the server side.
*/
uint8_t userdigest_md5[MHD_MD5_DIGEST_SIZE];
/**
* The SHA-256 hash of the username together with the realm.
* This hash can be used by the client to send the username in encrypted
* form.
* The purpose of userhash is to hide user identity when transmitting
* requests over insecure link.
*/
uint8_t userhash_sha256[MHD_SHA256_DIGEST_SIZE];
/**
* The SHA-256 hash of the username with the password and the realm.
* It is used to verify that password used by the client matches password
* required by the server.
* The purpose of userhash is to avoid keeping the password in cleartext
* on the server side.
*/
uint8_t userdigest_sha256[MHD_SHA256_DIGEST_SIZE];
/**
* The SHA-512/256 hash of the username together with the realm.
* This hash can be used by the client to send the username in encrypted
* form.
* The purpose of userhash is to hide user identity when transmitting
* requests over insecure link.
*/
uint8_t userhash_sha512_256[MHD_SHA512_256_DIGEST_SIZE];
/**
* The SHA-512/256 hash of the username with the password and the realm.
* It is used to verify that password used by the client matches password
* required by the server.
* The purpose of userhash is to avoid keeping the password in cleartext
* on the server side.
*/
uint8_t userdigest_sha512_256[MHD_SHA512_256_DIGEST_SIZE];
/**
* User has access to "area 1" if non-zero
*/
int allow_area_1;
/**
* User has access to "area 2" if non-zero
*/
int allow_area_2;
};
/**
* The array of user entries.
* In real application it should be loaded from external sources
* at the application startup.
*/
static struct UserEntry user_ids[2];
/**
* The number of entries used in @a user_ids.
*/
static size_t user_ids_used = 0;
/**
* Add new user to the users database/array.
*
* This kind of function must be used only when the new user is introduced.
* It must not be used at the every start of the application. The database
* of users should be stored somewhere and reloaded when application is
* started.
*
* @param username the username of the new user
* @param password the password of the new user
* @param realm the realm (the protection space) for which the new user
* is added
* @param allow_area_1 if non-zero than user has access to the "area 1"
* @param allow_area_2 if non-zero than user has access to the "area 2"
* @return non-zero on success,
* zero on failure (like no more space in the database).
*/
static int
add_new_user_entry (const char *const username,
const char *const password,
const char *const realm,
int allow_area_1,
int allow_area_2)
{
struct UserEntry *entry;
enum MHD_Result res;
if ((sizeof(user_ids) / sizeof(user_ids[0])) <= user_ids_used)
return 0; /* No more space to add new entry */
entry = user_ids + user_ids_used;
entry->username = username;
entry->realm = realm;
res = MHD_YES;
if (MHD_NO != res)
res = MHD_digest_auth_calc_userhash (MHD_DIGEST_AUTH_ALGO3_MD5,
username,
realm,
entry->userhash_md5,
sizeof(entry->userhash_md5));
if (MHD_NO != res)
res = MHD_digest_auth_calc_userdigest (MHD_DIGEST_AUTH_ALGO3_MD5,
username,
realm,
password,
entry->userdigest_md5,
sizeof(entry->userdigest_md5));
if (MHD_NO != res)
res = MHD_digest_auth_calc_userhash (MHD_DIGEST_AUTH_ALGO3_SHA256,
username,
realm,
entry->userhash_sha256,
sizeof(entry->userhash_sha256));
if (MHD_NO != res)
res = MHD_digest_auth_calc_userdigest (MHD_DIGEST_AUTH_ALGO3_SHA256,
username,
realm,
password,
entry->userdigest_sha256,
sizeof(entry->userdigest_sha256));
if (MHD_NO != res)
res = MHD_digest_auth_calc_userhash (MHD_DIGEST_AUTH_ALGO3_SHA512_256,
username,
realm,
entry->userhash_sha512_256,
sizeof(entry->userhash_sha512_256));
if (MHD_NO != res)
res =
MHD_digest_auth_calc_userdigest (MHD_DIGEST_AUTH_ALGO3_SHA512_256,
username,
realm,
password,
entry->userdigest_sha512_256,
sizeof(entry->userdigest_sha512_256));
if (MHD_NO == res)
return 0; /* Failure exit point */
entry->allow_area_1 = allow_area_1;
entry->allow_area_2 = allow_area_2;
user_ids_used++;
return ! 0;
}
/**
* Find the user entry for specified username
* @param username the username to find
* @return NULL if no entry for specified username is found,
* pointer to user entry if found
*/
static struct UserEntry *
find_entry_by_username (const char *const username)
{
size_t i;
for (i = 0; i < (sizeof(user_ids) / sizeof(user_ids[0])); ++i)
{
struct UserEntry *entry;
entry = user_ids + i;
if (0 == strcmp (username, entry->username))
return entry;
}
return NULL;
}
/**
* Find the user entry for specified userhash
* @param algo3 the algorithm used for userhash calculation
* @param userhash the userhash identifier to find
* @param userhash_size the size @a userhash in bytes
* @return NULL if no entry for specified userhash is found,
* pointer to user entry if found
*/
static struct UserEntry *
find_entry_by_userhash (enum MHD_DigestAuthAlgo3 algo3,
const void *userhash,
size_t userhash_size)
{
size_t i;
if (MHD_digest_get_hash_size (algo3) != userhash_size)
return NULL; /* Wrong length of the userhash */
switch (algo3)
{
case MHD_DIGEST_AUTH_ALGO3_MD5:
case MHD_DIGEST_AUTH_ALGO3_MD5_SESSION: /* An extra case not used currently */
if (sizeof(user_ids[0].userhash_md5) != userhash_size) /* Extra check. The size was checked before */
return NULL;
for (i = 0; i < (sizeof(user_ids) / sizeof(user_ids[0])); ++i)
{
struct UserEntry *entry;
entry = user_ids + i;
if (0 == memcmp (userhash, entry->userhash_md5,
sizeof(entry->userhash_md5)))
return entry;
}
break;
case MHD_DIGEST_AUTH_ALGO3_SHA256:
case MHD_DIGEST_AUTH_ALGO3_SHA256_SESSION: /* An extra case not used currently */
if (sizeof(user_ids[0].userhash_sha256) != userhash_size) /* Extra check. The size was checked before */
return NULL;
for (i = 0; i < (sizeof(user_ids) / sizeof(user_ids[0])); ++i)
{
struct UserEntry *entry;
entry = user_ids + i;
if (0 == memcmp (userhash, entry->userhash_sha256,
sizeof(entry->userhash_sha256)))
return entry;
}
break;
case MHD_DIGEST_AUTH_ALGO3_SHA512_256:
case MHD_DIGEST_AUTH_ALGO3_SHA512_256_SESSION: /* An extra case not used currently */
if (sizeof(user_ids[0].userhash_sha512_256) != userhash_size) /* Extra check. The size was checked before */
return NULL;
for (i = 0; i < (sizeof(user_ids) / sizeof(user_ids[0])); ++i)
{
struct UserEntry *entry;
entry = user_ids + i;
if (0 == memcmp (userhash, entry->userhash_sha512_256,
sizeof(entry->userhash_sha512_256)))
return entry;
}
break;
case MHD_DIGEST_AUTH_ALGO3_INVALID: /* Mute compiler warning. Impossible value in this context. */
default:
break;
}
return NULL;
}
/**
* Find the user entry for the user specified by provided username info
* @param user_info the pointer to the structure username info returned by MHD
* @return NULL if no entry for specified username info is found,
* pointer to user entry if found
*/
static struct UserEntry *
find_entry_by_userinfo (const struct MHD_DigestAuthUsernameInfo *username_info)
{
if (MHD_DIGEST_AUTH_UNAME_TYPE_STANDARD <= username_info->uname_type)
return find_entry_by_username (username_info->username);
if (MHD_DIGEST_AUTH_UNAME_TYPE_USERHASH == username_info->uname_type)
return find_entry_by_userhash (username_info->algo3,
username_info->userhash_bin,
username_info->userhash_hex_len / 2);
return NULL; /* Should be unreachable as all cases are covered before */
}
/* *** End of "database" of users and "database" functions *** */
/* *** Requests handling *** */
/**
* Send "Requested HTTP method is not supported" page
* @param c the connection structure
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_page_not_found (struct MHD_Connection *c)
{
static const char page_content[] =
"<html><head><title>Page Not Found</title></head>" \
"<body>The requested page not found.</body></html>";
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len,
page_content);
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp,
MHD_HTTP_HEADER_CONTENT_TYPE,
"text/html");
ret = MHD_queue_response (c, MHD_HTTP_NOT_FOUND, resp);
MHD_destroy_response (resp);
return ret;
}
/**
* Get enum MHD_DigestAuthMultiAlgo3 value to be used for authentication.
* @return the algorithm number/value
*/
static enum MHD_DigestAuthMultiAlgo3
get_m_algo (void)
{
if (force_md5)
return MHD_DIGEST_AUTH_MULT_ALGO3_MD5;
else if (force_sha256)
return MHD_DIGEST_AUTH_MULT_ALGO3_SHA256;
else if (force_sha512_256)
return MHD_DIGEST_AUTH_MULT_ALGO3_SHA512_256;
/* No forced algorithm selection, let MHD to use default */
return MHD_DIGEST_AUTH_MULT_ALGO3_ANY_NON_SESSION;
}
/**
* Get enum MHD_DigestAuthMultiQOP value to be used for authentication.
* @return the "Quality Of Protection" number/value
*/
static enum MHD_DigestAuthMultiQOP
get_m_QOP (void)
{
if (allow_rfc2069)
return MHD_DIGEST_AUTH_MULT_QOP_ANY_NON_INT;
return MHD_DIGEST_AUTH_MULT_QOP_AUTH;
}
/**
* Send "Authentication required" page
* @param c the connection structure
* @param stale if non-zero then "nonce stale" is indicated in the reply
* @param wrong_cred if non-zero then client is informed the previously
* it used wrong credentials
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_auth_required (struct MHD_Connection *c,
int stale,
int wrong_cred)
{
static const char auth_required_content[] =
"<html><head><title>Authentication required</title></head>" \
"<body>The requested page needs authentication.</body></html>";
static const size_t auth_required_content_len =
(sizeof(auth_required_content) / sizeof(char)) - 1;
static const char wrong_creds_content[] =
"<html><head><title>Wrong credentials</title></head>" \
"<body>The provided credentials are incorrect.</body></html>";
static const size_t wrong_creds_content_len =
(sizeof(wrong_creds_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
if (wrong_cred)
stale = 0; /* Force client to ask user for username and password */
if (! wrong_cred)
resp = MHD_create_response_from_buffer_static (auth_required_content_len,
auth_required_content);
else
resp = MHD_create_response_from_buffer_static (wrong_creds_content_len,
wrong_creds_content);
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp,
MHD_HTTP_HEADER_CONTENT_TYPE, "text/html");
ret = MHD_queue_auth_required_response3 (
c,
REALM,
OPAQUE_DATA, /* The "opaque data", not really useful */
SEC_AREA1_URL " " SEC_AREA2_URL, /* Space-separated list of URLs' initial parts */
resp,
stale,
get_m_QOP (),
get_m_algo (),
! 0, /* Userhash support enabled */
! 0 /* UTF-8 is preferred */);
MHD_destroy_response (resp);
return ret;
}
/**
* Send "Forbidden" page
* @param c the connection structure
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_forbidden (struct MHD_Connection *c)
{
static const char page_content[] =
"<html><head><title>Forbidden</title></head>" \
"<body>You do not have access to this page.</body></html>";
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len, page_content)
;
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp,
MHD_HTTP_HEADER_CONTENT_TYPE,
"text/html");
ret = MHD_queue_response (c, MHD_HTTP_FORBIDDEN, resp);
MHD_destroy_response (resp);
return ret;
}
/**
* Send "Area 1" pages
* @param c the connection structure
* @param url the requested URL
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_area1_pages (struct MHD_Connection *c,
const char *url)
{
if (0 == strcmp (url, SEC_AREA1_URL ""))
{
static const char page_content[] =
"<html><head><title>Restricted secret page</title></head>" \
"<body>Welcome to the restricted area</body></html>";
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len,
page_content);
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp, MHD_HTTP_HEADER_CONTENT_TYPE,
"text/html");
ret = MHD_queue_response (c, MHD_HTTP_OK, resp);
MHD_destroy_response (resp);
return ret;
}
/* If needed: add handlers for other URLs in this area */
#if 0 /* Disabled code */
if (0 == strcmp (url, SEC_AREA1_URL "some_path/some_page"))
{
/* Add page creation/processing code */
}
#endif /* Disabled code */
/* The requested URL is unknown */
return reply_with_page_not_found (c);
}
/**
* Send "Area 2" pages
* @param c the connection structure
* @param url the requested URL
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_area2_pages (struct MHD_Connection *c,
const char *url)
{
if (0 == strcmp (url, SEC_AREA2_URL ""))
{
static const char page_content[] =
"<html><head><title>Very restricted secret page</title></head>" \
"<body>Welcome to the super restricted area</body></html>";
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len,
page_content);
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp, MHD_HTTP_HEADER_CONTENT_TYPE,
"text/html");
ret = MHD_queue_response (c, MHD_HTTP_OK, resp);
MHD_destroy_response (resp);
return ret;
}
/* If needed: add handlers for other URLs in this area */
#if 0 /* Disabled code */
if (0 == strcmp (url, SEC_AREA2_URL "other_path/other_page"))
{
/* Add page creation/processing code */
}
#endif /* Disabled code */
/* The requested URL is unknown */
return reply_with_page_not_found (c);
}
/**
* Handle client's request for secured areas
* @param c the connection structure
* @param url the URL requested by the client
* @param sec_area_num the number of secured area
* @return MHD_YES if request was handled (either with "denied" or with
* "allowed" result),
* MHD_NO if it was an error handling the request.
*/
static enum MHD_Result
handle_sec_areas_req (struct MHD_Connection *c, const char *url, unsigned int
sec_area_num)
{
struct MHD_DigestAuthUsernameInfo *username_info;
struct UserEntry *user_entry;
void *userdigest;
size_t userdigest_size;
enum MHD_DigestAuthResult auth_res;
username_info = MHD_digest_auth_get_username3 (c);
if (NULL == username_info)
return reply_with_auth_required (c, 0, 0);
user_entry = find_entry_by_userinfo (username_info);
if (NULL == user_entry)
return reply_with_auth_required (c, 0, 1);
switch (username_info->algo3)
{
case MHD_DIGEST_AUTH_ALGO3_MD5:
userdigest = user_entry->userdigest_md5;
userdigest_size = sizeof(user_entry->userdigest_md5);
break;
case MHD_DIGEST_AUTH_ALGO3_SHA256:
userdigest = user_entry->userdigest_sha256;
userdigest_size = sizeof(user_entry->userdigest_sha256);
break;
case MHD_DIGEST_AUTH_ALGO3_SHA512_256:
userdigest = user_entry->userdigest_sha512_256;
userdigest_size = sizeof(user_entry->userdigest_sha512_256);
break;
case MHD_DIGEST_AUTH_ALGO3_MD5_SESSION:
case MHD_DIGEST_AUTH_ALGO3_SHA256_SESSION:
case MHD_DIGEST_AUTH_ALGO3_SHA512_256_SESSION:
/* Not supported currently and not used by MHD.
The client incorrectly used algorithm not advertised by the server. */
return reply_with_auth_required (c, 0, 1);
case MHD_DIGEST_AUTH_ALGO3_INVALID: /* Mute compiler warning */
default:
return MHD_NO; /* Should be unreachable */
}
auth_res = MHD_digest_auth_check_digest3 (
c,
REALM, /* Make sure to use the proper realm, not the realm provided by the client and returned by "user_entry" */
user_entry->username,
userdigest,
userdigest_size,
0, /* Use daemon's default value for nonce_timeout*/
0, /* Use daemon's default value for max_nc */
get_m_QOP (),
(enum MHD_DigestAuthMultiAlgo3) username_info->algo3 /* Direct cast from "single algorithm" to "multi-algorithm" is allowed */
);
if (MHD_DAUTH_OK != auth_res)
{
int need_just_refresh_nonce;
/* Actually MHD_DAUTH_NONCE_OTHER_COND should not be returned as
MHD_OPTION_DIGEST_AUTH_NONCE_BIND_TYPE is not used for the daemon.
To keep the code universal the MHD_DAUTH_NONCE_OTHER_COND is
still checked here. */
need_just_refresh_nonce =
(MHD_DAUTH_NONCE_STALE == auth_res)
|| (MHD_DAUTH_NONCE_OTHER_COND == auth_res);
return reply_with_auth_required (c,
need_just_refresh_nonce,
! need_just_refresh_nonce);
}
/* The user successfully authenticated */
/* Check whether access to the request area is allowed for the user */
if (1 == sec_area_num)
{
if (user_entry->allow_area_1)
return reply_with_area1_pages (c, url);
else
return reply_with_forbidden (c);
}
else if (2 == sec_area_num)
{
if (user_entry->allow_area_2)
return reply_with_area2_pages (c, url);
else
return reply_with_forbidden (c);
}
return MHD_NO; /* Should be unreachable */
}
/**
* Send the main page
* @param c the connection structure
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_main_page (struct MHD_Connection *c)
{
static const char page_content[] = MAIN_PAGE;
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len, page_content)
;
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp,
MHD_HTTP_HEADER_CONTENT_TYPE,
"text/html");
ret = MHD_queue_response (c, MHD_HTTP_OK, resp);
MHD_destroy_response (resp);
return ret;
}
/**
* Send "Requested HTTP method is not supported" page
* @param c the connection structure
* @return MHD_YES if response was successfully queued,
* MHD_NO otherwise
*/
static enum MHD_Result
reply_with_method_not_supported (struct MHD_Connection *c)
{
static const char page_content[] =
"<html><head><title>Requested HTTP Method Is Not Supported</title></head>" \
"<body>The requested HTTP method is not supported.</body></html>";
static const size_t page_content_len =
(sizeof(page_content) / sizeof(char)) - 1;
struct MHD_Response *resp;
enum MHD_Result ret;
resp = MHD_create_response_from_buffer_static (page_content_len, page_content)
;
if (NULL == resp)
return MHD_NO;
/* Ignore possible error when adding the header as the reply will work even
without this header. */
(void) MHD_add_response_header (resp,
MHD_HTTP_HEADER_CONTENT_TYPE, "text/html");
ret = MHD_queue_response (c, MHD_HTTP_NOT_IMPLEMENTED, resp);
MHD_destroy_response (resp);
return ret;
}
static enum MHD_Result
ahc_main (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 **req_cls)
{
static int already_called_marker;
size_t url_len;
(void) cls; /* Unused. Silent compiler warning. */
(void) version; /* Unused. Silent compiler warning. */
(void) upload_data; /* Unused. Silent compiler warning. */
if ((0 != strcmp (method, MHD_HTTP_METHOD_GET))
&& (0 != strcmp (method, MHD_HTTP_METHOD_HEAD)))
return reply_with_method_not_supported (connection);
if (0 != *upload_data_size)
return MHD_NO; /* No upload expected for GET or HEAD */
if (&already_called_marker != *req_cls)
{ /* Called for the first time, request not fully read yet */
*req_cls = &already_called_marker;
/* Wait for complete request */
return MHD_YES;
}
if (0 == strcmp (url, "/"))
return reply_with_main_page (connection);
url_len = strlen (url);
if ((strlen (SEC_AREA1_URL) <= url_len)
&& (0 == memcmp (url, SEC_AREA1_URL, strlen (SEC_AREA1_URL))))
return handle_sec_areas_req (connection, url, 1); /* The requested URL is within SEC_AREA1_URL */
if ((strlen (SEC_AREA2_URL) <= url_len)
&& (0 == memcmp (url, SEC_AREA2_URL, strlen (SEC_AREA2_URL))))
return handle_sec_areas_req (connection, url, 2); /* The requested URL is within SEC_AREA2_URL */
return reply_with_page_not_found (connection);
}
/* *** End of requests handling *** */
/**
* Add new users to the users "database".
*
* In real application this kind of function must NOT be called at
* the application startup. Instead similar function should be
* called only when new user is introduced. The users "database"
* should be stored somewhere and reloaded at the application
* startup.
*
* @return non-zero on success,
* zero in case of error.
*/
static int
add_new_users (void)
{
if (! add_new_user_entry ("joepublic",
"password",
REALM,
! 0,
0))
return 0;
if (! add_new_user_entry ("superadmin",
"pA$$w0Rd",
REALM,
! 0,
! 0))
return 0;
return ! 0;
}
/**
* Check and apply application parameters
* @param argc the argc of the @a main function
* @param argv the argv of the @a main function
* @return non-zero on success,
* zero in case of any error (like wrong parameters).
*/
static int
check_params (int argc, char *const *const argv)
{
size_t i;
unsigned int port_value;
if (2 > argc)
return 0;
for (i = 1; i < (unsigned int) argc; ++i)
{
if (0 == strcmp (argv[i], "--md5"))
{ /* Force use MD5 */
force_md5 = ! 0;
force_sha256 = 0;
force_sha512_256 = 0;
}
else if (0 == strcmp (argv[i], "--sha256"))
{ /* Force use SHA-256 instead of default MD5 */
force_md5 = 0;
force_sha256 = ! 0;
force_sha512_256 = 0;
}
else if (0 == strcmp (argv[i], "--sha512-256"))
{ /* Force use SHA-512/256 instead of default MD5 */
force_md5 = 0;
force_sha256 = 0;
force_sha512_256 = ! 0;
}
else if (0 == strcmp (argv[i], "--allow-rfc2069"))
allow_rfc2069 = ! 0; /* Allow fallback to RFC2069. Not recommended! */
else if ((1 == sscanf (argv[i], "%u", &port_value))
&& (0 < port_value) && (65535 >= port_value))
daemon_port = (uint16_t) port_value;
else
{
fprintf (stderr, "Unrecognized parameter: %s\n",
argv[i]);
return 0;
}
}
if (force_sha512_256)
printf (
"Note: when testing with curl/libcurl do not be surprised with failures as "
"libcurl incorrectly implements SHA-512/256 algorithm.\n");
return ! 0;
}
/**
* The cryptographically secure random data
*/
static uint8_t rand_data[8];
/**
* Initialise the random data
* @return non-zero if succeed,
* zero if failed
*/
static int
init_rand_data (void)
{
#if ! defined(_WIN32) || defined(__CYGWIN__)
int fd;
ssize_t len;
size_t off;
fd = open ("/dev/urandom", O_RDONLY);
if (-1 == fd)
{
fprintf (stderr, "Failed to open '%s': %s\n",
"/dev/urandom",
strerror (errno));
return 0;
}
for (off = 0; off < sizeof(rand_data); off += (size_t) len)
{
len = read (fd, rand_data, 8);
if (0 > len)
{
fprintf (stderr, "Failed to read '%s': %s\n",
"/dev/urandom",
strerror (errno));
(void) close (fd);
return 0;
}
}
(void) close (fd);
#else /* Native W32 */
HCRYPTPROV cc;
BOOL b;
b = CryptAcquireContext (&cc,
NULL,
NULL,
PROV_RSA_FULL,
CRYPT_VERIFYCONTEXT);
if (FALSE == b)
{
fprintf (stderr,
"Failed to acquire crypto provider context: %lu\n",
(unsigned long) GetLastError ());
return 0;
}
b = CryptGenRandom (cc, sizeof(rand_data), (BYTE *) rand_data);
if (FALSE == b)
{
fprintf (stderr,
"Failed to generate 8 random bytes: %lu\n",
GetLastError ());
}
CryptReleaseContext (cc, 0);
if (FALSE == b)
return 0;
#endif /* Native W32 */
return ! 0;
}
int
main (int argc, char *const *argv)
{
struct MHD_Daemon *d;
if (! check_params (argc, argv))
{
fprintf (stderr, "Usage: %s [--md5|--sha256|--sha512-256] "
"[--allow-rfc2069] PORT\n", argv[0]);
return 1;
}
if (! add_new_users ())
{
fprintf (stderr, "Failed to add new users to the users database.\n");
return 2;
}
if (! init_rand_data ())
{
fprintf (stderr, "Failed to initialise random data.\n");
return 2;
}
d = MHD_start_daemon (
MHD_USE_INTERNAL_POLLING_THREAD
| MHD_USE_THREAD_PER_CONNECTION
| MHD_USE_ERROR_LOG,
daemon_port,
NULL, NULL, &ahc_main, NULL,
MHD_OPTION_DIGEST_AUTH_RANDOM, sizeof(rand_data), rand_data,
MHD_OPTION_NONCE_NC_SIZE, 500,
MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 180,
MHD_OPTION_END);
if (d == NULL)
{
fprintf (stderr, "Failed to start the server on port %lu.\n",
(unsigned long) daemon_port);
return 1;
}
printf ("Running server on port %lu.\nPress ENTER to stop.\n",
(unsigned long) daemon_port);
(void) getc (stdin);
MHD_stop_daemon (d);
return 0;
}
/* End of digest_auth_example_adv.c */
|
