Files
MaxScale/server/modules/protocol/maxscaled.c
2016-08-29 14:09:14 +03:00

386 lines
10 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/bsl.
*
* Change Date: 2019-01-01
*
* 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <dcb.h>
#include <buffer.h>
#include <gw_protocol.h>
#include <service.h>
#include <session.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <router.h>
#include <maxscale/poll.h>
#include <atomic.h>
#include <gw.h>
#include <adminusers.h>
#include <skygw_utils.h>
#include <log_manager.h>
#include <modinfo.h>
#include <maxscaled.h>
#include <maxadmin.h>
/* @see function load_module in load_utils.c for explanation of the following
* lint directives.
*/
/*lint -e14 */
MODULE_INFO info =
{
MODULE_API_PROTOCOL,
MODULE_GA,
GWPROTOCOL_VERSION,
"A maxscale protocol for the administration interface"
};
/*lint +e14 */
/**
* @file maxscaled.c - MaxScale administration protocol
*
*
* @verbatim
* Revision History
* Date Who Description
* 13/06/2014 Mark Riddoch Initial implementation
* 07/07/2015 Martin Brampton Correct failure handling
* 17/05/2016 Massimiliano Pinto Check for UNIX socket address
*
* @endverbatim
*/
static char *version_str = "V2.0.0";
static int maxscaled_read_event(DCB* dcb);
static int maxscaled_write_event(DCB *dcb);
static int maxscaled_write(DCB *dcb, GWBUF *queue);
static int maxscaled_error(DCB *dcb);
static int maxscaled_hangup(DCB *dcb);
static int maxscaled_accept(DCB *dcb);
static int maxscaled_close(DCB *dcb);
static int maxscaled_listen(DCB *dcb, char *config);
static char *mxsd_default_auth();
/**
* The "module object" for the maxscaled protocol module.
*/
static GWPROTOCOL MyObject =
{
maxscaled_read_event, /**< Read - EPOLLIN handler */
maxscaled_write, /**< Write - data from gateway */
maxscaled_write_event, /**< WriteReady - EPOLLOUT handler */
maxscaled_error, /**< Error - EPOLLERR handler */
maxscaled_hangup, /**< HangUp - EPOLLHUP handler */
maxscaled_accept, /**< Accept */
NULL, /**< Connect */
maxscaled_close, /**< Close */
maxscaled_listen, /**< Create a listener */
NULL, /**< Authentication */
NULL, /**< Session */
mxsd_default_auth, /**< Default authenticator */
NULL /**< Connection limit reached */
};
/**
* Implementation of the mandatory version entry point
*
* @return version string of the module
*
* @see function load_module in load_utils.c for explanation of the following
* lint directives.
*/
/*lint -e14 */
char* version()
{
return version_str;
}
/**
* The module initialisation routine, called when the module
* is first loaded.
*/
void ModuleInit()
{
MXS_INFO("Initialise MaxScaled Protocol module.");;
}
/**
* 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
*/
GWPROTOCOL* GetModuleObject()
{
return &MyObject;
}
/*lint +e14 */
/**
* The default authenticator name for this protocol
*
* @return name of authenticator
*/
static char *mxsd_default_auth()
{
return "MaxAdminAuth";
}
/**
* Read event for EPOLLIN on the maxscaled protocol module.
*
* @param dcb The descriptor control block
* @return
*/
static int maxscaled_read_event(DCB* dcb)
{
int n;
GWBUF *head = NULL;
MAXSCALED *maxscaled = (MAXSCALED *)dcb->protocol;
if ((n = dcb_read(dcb, &head, 0)) != -1)
{
if (head)
{
if (GWBUF_LENGTH(head))
{
if (maxscaled->state == MAXSCALED_STATE_DATA)
{
SESSION_ROUTE_QUERY(dcb->session, head);
dcb_printf(dcb, "OK");
}
}
else
{
// Force the free of the buffer header
gwbuf_free(head);
}
}
}
return n;
}
/**
* EPOLLOUT handler for the maxscaled protocol module.
*
* @param dcb The descriptor control block
* @return
*/
static int maxscaled_write_event(DCB *dcb)
{
return dcb_drain_writeq(dcb);
}
/**
* Write routine for the maxscaled protocol module.
*
* Writes the content of the buffer queue to the socket
* observing the non-blocking principles of MaxScale.
*
* @param dcb Descriptor Control Block for the socket
* @param queue Linked list of buffes to write
*/
static int maxscaled_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 maxscaled_error(DCB *dcb)
{
return 0;
}
/**
* Handler for the EPOLLHUP event.
*
* @param dcb The descriptor control block
*/
static int maxscaled_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 dcb The descriptor control block
* @return The number of new connections created
*/
static int maxscaled_accept(DCB *listener)
{
int n_connect = 0;
DCB *client_dcb;
socklen_t len = sizeof(struct ucred);
struct ucred ucred;
while ((client_dcb = dcb_accept(listener, &MyObject)) != NULL)
{
MAXSCALED *maxscaled_protocol = NULL;
if ((maxscaled_protocol = (MAXSCALED *)calloc(1, sizeof(MAXSCALED))) == NULL)
{
dcb_close(client_dcb);
continue;
}
maxscaled_protocol->username = NULL;
maxscaled_protocol->state = MAXSCALED_STATE_LOGIN;
/* Get UNIX client credentials from socket*/
if (getsockopt(client_dcb->fd, SOL_SOCKET, SO_PEERCRED, &ucred, &len) == -1)
{
MXS_ERROR("Failed to get UNIX socket credentials for 'MaxScale Admin'");
dcb_close(client_dcb);
continue;
}
else
{
struct passwd pw_entry;
struct passwd *pw_tmp;
char buf[MAXADMIN_GETPWUID_BUF_LEN];
/* Fetch username from UID */
if (!getpwuid_r(ucred.uid, &pw_entry, buf, sizeof(buf), &pw_tmp))
{
GWBUF *username;
/* Set user in protocol */
maxscaled_protocol->username = strdup(pw_entry.pw_name);
username = gwbuf_alloc(strlen(maxscaled_protocol->username) + 1);
strcpy(GWBUF_DATA(username), maxscaled_protocol->username);
/* Authenticate the user */
if (client_dcb->authfunc.extract(client_dcb, username) == 0 &&
client_dcb->authfunc.authenticate(client_dcb) == 0)
{
dcb_printf(client_dcb, "OK----");
maxscaled_protocol->state = MAXSCALED_STATE_DATA;
client_dcb->user = strdup(maxscaled_protocol->username);
}
else
{
dcb_printf(client_dcb, "FAILED");
}
}
else
{
MXS_ERROR("Failed to get UNIX user %ld details for 'MaxScale Admin'",
(unsigned long)ucred.uid);
dcb_close(client_dcb);
continue;
}
}
spinlock_init(&maxscaled_protocol->lock);
client_dcb->protocol = (void *)maxscaled_protocol;
client_dcb->session = session_alloc(listener->session->service, client_dcb);
if (NULL == client_dcb->session || poll_add_dcb(client_dcb))
{
dcb_close(client_dcb);
continue;
}
n_connect++;
}
return n_connect;
}
/**
* The close handler for the descriptor. Called by the gateway to
* explicitly close a connection.
*
* @param dcb The descriptor control block
*/
static int maxscaled_close(DCB *dcb)
{
MAXSCALED *maxscaled = dcb->protocol;
if (!maxscaled)
{
return 0;
}
spinlock_acquire(&maxscaled->lock);
if (maxscaled->username)
{
free(maxscaled->username);
maxscaled->username = NULL;
}
spinlock_release(&maxscaled->lock);
return 0;
}
/**
* Maxscale daemon listener entry point
*
* @param listener The Listener DCB
* @param config Configuration (ip:port)
* @return 0 on failure, 1 on success
*/
static int maxscaled_listen(DCB *listener, char *config)
{
char *socket_path = NULL;
/* check for default UNIX socket */
if (strncmp(config, MAXADMIN_CONFIG_DEFAULT_SOCKET_TAG, MAXADMIN_CONFIG_DEFAULT_SOCKET_TAG_LEN) == 0)
{
socket_path = MAXADMIN_DEFAULT_SOCKET;
}
else
{
const char* colon = strchr(config, ':');
ss_dassert(colon);
const char* port = colon + 1;
if (*port == '0')
{
// It seems "socket=socket-path" has been specified.
// The colon etc. will be stripped away in dcb_listen_create_socket_unix.
socket_path = config;
}
else
{
MXS_WARNING("The 'maxscaled' protocol can only be used with a Unix domain socket, but "
"it seems to have been configured with an address and port: %s. "
"Using the default socket path instead: %s. "
"Remove all 'address' and 'port' entries from maxscaled protocol "
"listeners and replace with 'socket=default' or 'socket=path-to-socket'.",
config, MAXADMIN_DEFAULT_SOCKET);
socket_path = MAXADMIN_DEFAULT_SOCKET;
}
}
return (dcb_listen(listener, socket_path, "MaxScale Admin") < 0) ? 0 : 1;
}