2019-06-25 10:11:55 +03:00

468 lines
12 KiB
C++

/*
* Copyright (c) 2016 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2023-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
/**
* @file httpd.c - HTTP daemon protocol module
*
* The httpd protocol module is intended as a mechanism to allow connections
* into the gateway for the purpose of accessing information within
* the gateway with a REST interface
* databases.
*
* In the first instance it is intended to allow a debug connection to access
* internal data structures, however it may also be used to manage the
* configuration of the gateway via REST interface.
*
* @verbatim
* Revision History
* Date Who Description
* 08/07/2013 Massimiliano Pinto Initial version
* 09/07/2013 Massimiliano Pinto Added /show?dcb|session for all dcbs|sessions
*
* @endverbatim
*/
#define MXS_MODULE_NAME "HTTPD"
#include "httpd.hh"
#include <ctype.h>
#include <maxbase/alloc.h>
#include <maxscale/protocol.hh>
#include <maxscale/modinfo.h>
#include <maxscale/resultset.hh>
#define ISspace(x) isspace((int)(x))
#define HTTP_SERVER_STRING "MaxScale(c) v.1.0.0"
static int httpd_read_event(DCB* dcb);
static int httpd_write_event(DCB* dcb);
static int httpd_write(DCB* dcb, GWBUF* queue);
static int httpd_error(DCB* dcb);
static int httpd_hangup(DCB* dcb);
static int httpd_accept(DCB*);
static int httpd_close(DCB* dcb);
static int httpd_get_line(int sock, char* buf, int size);
static void httpd_send_headers(DCB* dcb, int final, bool auth_ok);
static char* httpd_default_auth();
extern "C"
{
/**
* The module entry point routine. It is this routine that
* must populate the structure that is referred to as the
* "module object", this is a structure with the set of
* external entry points for this module.
*
* @return The module object
*/
MXS_MODULE* MXS_CREATE_MODULE()
{
static MXS_PROTOCOL MyObject =
{
httpd_read_event, /**< Read - EPOLLIN handler */
httpd_write, /**< Write - data from gateway */
httpd_write_event, /**< WriteReady - EPOLLOUT handler */
httpd_error, /**< Error - EPOLLERR handler */
httpd_hangup, /**< HangUp - EPOLLHUP handler */
httpd_accept, /**< Accept */
NULL, /**< Connect */
httpd_close, /**< Close */
NULL, /**< Authentication */
httpd_default_auth, /**< Default authenticator */
NULL, /**< Connection limit reached */
NULL,
NULL,
};
static MXS_MODULE info =
{
MXS_MODULE_API_PROTOCOL,
MXS_MODULE_IN_DEVELOPMENT,
MXS_PROTOCOL_VERSION,
"An experimental HTTPD implementation for use in administration",
"V1.2.0",
MXS_NO_MODULE_CAPABILITIES,
&MyObject,
NULL, /* Process init. */
NULL, /* Process finish. */
NULL, /* Thread init. */
NULL, /* Thread finish. */
{
{MXS_END_MODULE_PARAMS}
}
};
return &info;
}
}
/*lint +e14 */
static const char* default_auth = "NullAuthAllow";
/**
* The default authenticator name for this protocol
*
* @return name of authenticator
*/
static char* httpd_default_auth()
{
return (char*)default_auth;
}
/**
* Read event for EPOLLIN on the httpd protocol module.
*
* @param dcb The descriptor control block
* @return
*/
static int httpd_read_event(DCB* dcb)
{
MXS_SESSION* session = dcb->session;
int numchars = 1;
char buf[HTTPD_REQUESTLINE_MAXLEN - 1] = "";
char* query_string = NULL;
char method[HTTPD_METHOD_MAXLEN - 1] = "";
char url[HTTPD_SMALL_BUFFER] = "";
size_t i, j;
int headers_read = 0;
HTTPD_session* client_data = NULL;
GWBUF* uri;
client_data = static_cast<HTTPD_session*>(dcb->data);
/**
* get the request line
* METHOD URL HTTP_VER\r\n
*/
numchars = httpd_get_line(dcb->fd, buf, sizeof(buf));
i = 0;
j = 0;
while (!ISspace(buf[j]) && (i < sizeof(method) - 1))
{
method[i] = buf[j];
i++;
j++;
}
method[i] = '\0';
strcpy(client_data->method, method);
/* check allowed http methods */
if (strcasecmp(method, "GET") && strcasecmp(method, "POST"))
{
// httpd_unimplemented(dcb->fd);
return 0;
}
i = 0;
while ((j < sizeof(buf)) && ISspace(buf[j]))
{
j++;
}
while ((j < sizeof(buf) - 1) && !ISspace(buf[j]) && (i < sizeof(url) - 1))
{
url[i] = buf[j];
i++;
j++;
}
url[i] = '\0';
/**
* Get the query string if availble
*/
if (strcasecmp(method, "GET") == 0)
{
query_string = url;
while ((*query_string != '?') && (*query_string != '\0'))
{
query_string++;
}
if (*query_string == '?')
{
*query_string = '\0';
}
}
/** If listener->authenticator is the default authenticator, it means that
* we don't need to check the user credentials. All other authenticators
* cause a 401 Unauthorized to be returned on the first try. */
bool auth_ok = httpd_default_auth() == std::string(dcb->session->listener->authenticator());
/**
* Get the request headers
*/
while ((numchars > 0) && strcmp("\n", buf))
{
char* value = NULL;
char* end = NULL;
numchars = httpd_get_line(dcb->fd, buf, sizeof(buf));
if ((value = strchr(buf, ':')))
{
*value = '\0';
value++;
end = &value[strlen(value) - 1];
*end = '\0';
if (strncasecmp(buf, "Hostname", 6) == 0)
{
strcpy(client_data->hostname, value);
}
if (strncasecmp(buf, "useragent", 9) == 0)
{
strcpy(client_data->useragent, value);
}
if (strcmp(buf, "Authorization") == 0)
{
GWBUF* auth_data = gwbuf_alloc_and_load(strlen(value), value);
MXS_OOM_IFNULL(auth_data);
if (auth_data)
{
/** The freeing entry point is called automatically when
* the client DCB is closed */
dcb->authfunc.extract(dcb, auth_data);
auth_ok = dcb->authfunc.authenticate(dcb) == MXS_AUTH_SUCCEEDED;
gwbuf_free(auth_data);
}
}
}
}
if (numchars)
{
headers_read = 1;
memcpy(&client_data->headers_received, &headers_read, sizeof(int));
}
/**
* Now begins the server reply
*/
/* send all the basic headers and close with \r\n */
httpd_send_headers(dcb, 1, auth_ok);
#if 0
/**
* ToDO: launch proper content handling based on the requested URI, later REST interface
*
*/
if (strcmp(url, "/show") == 0)
{
if (query_string && strlen(query_string))
{
if (strcmp(query_string, "dcb") == 0)
{
dprintAllDCBs(dcb);
}
if (strcmp(query_string, "session") == 0)
{
dprintAllSessions(dcb);
}
}
}
if (strcmp(url, "/services") == 0)
{
ResultSet* set, * seviceGetList();
if ((set = serviceGetList()) != NULL)
{
resultset_stream_json(set, dcb);
resultset_free(set);
}
}
#endif
if (auth_ok && (uri = gwbuf_alloc(strlen(url) + 1)) != NULL)
{
strcpy((char*)GWBUF_DATA(uri), url);
gwbuf_set_type(uri, GWBUF_TYPE_HTTP);
MXS_SESSION_ROUTE_QUERY(session, uri);
}
/* force the client connecton close */
dcb_close(dcb);
return 0;
}
/**
* EPOLLOUT handler for the HTTPD protocol module.
*
* @param dcb The descriptor control block
* @return
*/
static int httpd_write_event(DCB* dcb)
{
return dcb_drain_writeq(dcb);
}
/**
* Write routine for the HTTPD protocol module.
*
* Writes the content of the buffer queue to the socket
* observing the non-blocking principles of the gateway.
*
* @param dcb Descriptor Control Block for the socket
* @param queue Linked list of buffes to write
*/
static int httpd_write(DCB* dcb, GWBUF* queue)
{
int rc;
rc = dcb_write(dcb, queue);
return rc;
}
/**
* Handler for the EPOLLERR event.
*
* @param dcb The descriptor control block
*/
static int httpd_error(DCB* dcb)
{
dcb_close(dcb);
return 0;
}
/**
* Handler for the EPOLLHUP event.
*
* @param dcb The descriptor control block
*/
static int httpd_hangup(DCB* dcb)
{
dcb_close(dcb);
return 0;
}
/**
* Handler for the EPOLLIN event when the DCB refers to the listening
* socket for the protocol.
*
* @param listener The descriptor control block
*/
static int httpd_accept(DCB* client_dcb)
{
HTTPD_session* client_data = NULL;
/* create the session data for HTTPD */
if ((client_data = (HTTPD_session*)MXS_CALLOC(1, sizeof(HTTPD_session))) == NULL)
{
dcb_close(client_dcb);
return 0;
}
client_dcb->data = client_data;
if (!session_start(client_dcb->session) || poll_add_dcb(client_dcb) == -1)
{
dcb_close(client_dcb);
return 0;
}
return 1;
}
/**
* The close handler for the descriptor. Called by the gateway to
* explicitly close a connection.
*
* @param dcb The descriptor control block
*/
static int httpd_close(DCB* dcb)
{
return 0;
}
/**
* HTTPD get line from client
*/
static int httpd_get_line(int sock, char* buf, int size)
{
int i = 0;
char c = '\0';
int n;
while ((i < size - 1) && (c != '\n'))
{
n = recv(sock, &c, 1, 0);
/* DEBUG printf("%02X\n", c); */
if (n > 0)
{
if (c == '\r')
{
n = recv(sock, &c, 1, MSG_PEEK);
/* DEBUG printf("%02X\n", c); */
if ((n > 0) && (c == '\n'))
{
if (recv(sock, &c, 1, 0) < 0)
{
c = '\n';
}
}
else
{
c = '\n';
}
}
buf[i] = c;
i++;
}
else
{
c = '\n';
}
}
buf[i] = '\0';
return i;
}
/**
* HTTPD send basic headers with 200 OK
*/
static void httpd_send_headers(DCB* dcb, int final, bool auth_ok)
{
char date[64] = "";
const char* fmt = "%a, %d %b %Y %H:%M:%S GMT";
time_t httpd_current_time = time(NULL);
struct tm tm;
localtime_r(&httpd_current_time, &tm);
strftime(date, sizeof(date), fmt, &tm);
const char* response = auth_ok ? "200 OK" : "401 Unauthorized";
dcb_printf(dcb,
"HTTP/1.1 %s\r\n"
"Date: %s\r\n"
"Server: %s\r\n"
"Connection: close\r\n"
"WWW-Authenticate: Basic realm=\"MaxInfo\"\r\n"
"Content-Type: application/json\r\n",
response,
date,
HTTP_SERVER_STRING);
/* close the headers */
if (final)
{
dcb_printf(dcb, "\r\n");
}
}