MaxScale/server/modules/protocol/mysql_client.c
VilhoRaatikka 44771dbc51 readwritesplit.c:handleError is meant to handle backend errors. Removed one call from mysql_client.c and only send error message to client instead.
Added checks to debug build to ensure that handleError is called before backend DCB is closed.
2014-11-07 17:55:05 +02:00

1565 lines
51 KiB
C

/*
* This file is distributed as part of the MariaDB Corporation MaxScale. It is free
* software: you can redistribute it and/or modify it under the terms of the
* GNU General Public License as published by the Free Software Foundation,
* version 2.
*
* This program 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 General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Copyright MariaDB Corporation Ab 2013-2014
*/
/**
* @file mysql_client.c
*
* MySQL Protocol module for handling the protocol between the gateway
* and the client.
*
* Revision History
* Date Who Description
* 14/06/2013 Mark Riddoch Initial version
* 17/06/2013 Massimiliano Pinto Added Client To MaxScale routines
* 24/06/2013 Massimiliano Pinto Added: fetch passwords from service users' hashtable
* 02/09/2013 Massimiliano Pinto Added: session refcount
* 16/12/2013 Massimiliano Pinto Added: client closed socket detection with recv(..., MSG_PEEK)
* 24/02/2014 Massimiliano Pinto Added: on failed authentication a new users' table is loaded with time and frequency limitations
* If current user is authenticated the new users' table will replace the old one
* 28/02/2014 Massimiliano Pinto Added: client IPv4 in dcb->ipv4 and inet_ntop for string representation
* 11/03/2014 Massimiliano Pinto Added: Unix socket support
* 07/05/2014 Massimiliano Pinto Added: specific version string in server handshake
* 09/09/2014 Massimiliano Pinto Added: 777 permission for socket path
* 13/10/2014 Massimiliano Pinto Added: dbname authentication check
*
*/
#include <skygw_utils.h>
#include <log_manager.h>
#include <mysql_client_server_protocol.h>
#include <gw.h>
#include <modinfo.h>
#include <sys/stat.h>
#include <modutil.h>
MODULE_INFO info = {
MODULE_API_PROTOCOL,
MODULE_BETA_RELEASE,
GWPROTOCOL_VERSION,
"The client to MaxScale MySQL protocol implementation"
};
extern int lm_enabled_logfiles_bitmask;
static char *version_str = "V1.0.0";
static int gw_MySQLAccept(DCB *listener);
static int gw_MySQLListener(DCB *listener, char *config_bind);
static int gw_read_client_event(DCB* dcb);
static int gw_write_client_event(DCB *dcb);
static int gw_MySQLWrite_client(DCB *dcb, GWBUF *queue);
static int gw_error_client_event(DCB *dcb);
static int gw_client_close(DCB *dcb);
static int gw_client_hangup_event(DCB *dcb);
int mysql_send_ok(DCB *dcb, int packet_number, int in_affected_rows, const char* mysql_message);
int MySQLSendHandshake(DCB* dcb);
static int gw_mysql_do_authentication(DCB *dcb, GWBUF *queue);
static int route_by_statement(SESSION *, GWBUF **);
extern char* get_username_from_auth(char* ptr, uint8_t* data);
extern int check_db_name_after_auth(DCB *, char *, int);
extern char* create_auth_fail_str(char *username, char *hostaddr, char *sha1, char *db);
/*
* The "module object" for the mysqld client protocol module.
*/
static GWPROTOCOL MyObject = {
gw_read_client_event, /* Read - EPOLLIN handler */
gw_MySQLWrite_client, /* Write - data from gateway */
gw_write_client_event, /* WriteReady - EPOLLOUT handler */
gw_error_client_event, /* Error - EPOLLERR handler */
gw_client_hangup_event, /* HangUp - EPOLLHUP handler */
gw_MySQLAccept, /* Accept */
NULL, /* Connect */
gw_client_close, /* Close */
gw_MySQLListener, /* Listen */
NULL, /* Authentication */
NULL /* Session */
};
/**
* Implementation of the mandatory version entry point
*
* @return version string of the module
*/
char *
version()
{
return version_str;
}
/**
* The module initialisation routine, called when the module
* is first loaded.
*/
void
ModuleInit()
{
}
/**
* 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;
}
/**
* mysql_send_ok
*
* Send a MySQL protocol OK message to the dcb (client)
*
* @param dcb Descriptor Control Block for the connection to which the OK is sent
* @param packet_number
* @param in_affected_rows
* @param mysql_message
* @return packet length
*
*/
int
mysql_send_ok(DCB *dcb, int packet_number, int in_affected_rows, const char* mysql_message) {
uint8_t *outbuf = NULL;
uint8_t mysql_payload_size = 0;
uint8_t mysql_packet_header[4];
uint8_t *mysql_payload = NULL;
uint8_t field_count = 0;
uint8_t affected_rows = 0;
uint8_t insert_id = 0;
uint8_t mysql_server_status[2];
uint8_t mysql_warning_count[2];
GWBUF *buf;
affected_rows = in_affected_rows;
mysql_payload_size = sizeof(field_count) +
sizeof(affected_rows) +
sizeof(insert_id) +
sizeof(mysql_server_status) +
sizeof(mysql_warning_count);
if (mysql_message != NULL) {
mysql_payload_size += strlen(mysql_message);
}
// allocate memory for packet header + payload
if ((buf = gwbuf_alloc(sizeof(mysql_packet_header) + mysql_payload_size)) == NULL)
{
return 0;
}
outbuf = GWBUF_DATA(buf);
// write packet header with packet number
gw_mysql_set_byte3(mysql_packet_header, mysql_payload_size);
mysql_packet_header[3] = packet_number;
// write header
memcpy(outbuf, mysql_packet_header, sizeof(mysql_packet_header));
mysql_payload = outbuf + sizeof(mysql_packet_header);
mysql_server_status[0] = 2;
mysql_server_status[1] = 0;
mysql_warning_count[0] = 0;
mysql_warning_count[1] = 0;
// write data
memcpy(mysql_payload, &field_count, sizeof(field_count));
mysql_payload = mysql_payload + sizeof(field_count);
memcpy(mysql_payload, &affected_rows, sizeof(affected_rows));
mysql_payload = mysql_payload + sizeof(affected_rows);
memcpy(mysql_payload, &insert_id, sizeof(insert_id));
mysql_payload = mysql_payload + sizeof(insert_id);
memcpy(mysql_payload, mysql_server_status, sizeof(mysql_server_status));
mysql_payload = mysql_payload + sizeof(mysql_server_status);
memcpy(mysql_payload, mysql_warning_count, sizeof(mysql_warning_count));
mysql_payload = mysql_payload + sizeof(mysql_warning_count);
if (mysql_message != NULL) {
memcpy(mysql_payload, mysql_message, strlen(mysql_message));
}
// writing data in the Client buffer queue
dcb->func.write(dcb, buf);
return sizeof(mysql_packet_header) + mysql_payload_size;
}
/**
* MySQLSendHandshake
*
* @param dcb The descriptor control block to use for sending the handshake request
* @return The packet length sent
*/
int
MySQLSendHandshake(DCB* dcb)
{
uint8_t *outbuf = NULL;
uint8_t mysql_payload_size = 0;
uint8_t mysql_packet_header[4];
uint8_t mysql_packet_id = 0;
uint8_t mysql_filler = GW_MYSQL_HANDSHAKE_FILLER;
uint8_t mysql_protocol_version = GW_MYSQL_PROTOCOL_VERSION;
uint8_t *mysql_handshake_payload = NULL;
uint8_t mysql_thread_id[4];
uint8_t mysql_scramble_buf[9] = "";
uint8_t mysql_plugin_data[13] = "";
uint8_t mysql_server_capabilities_one[2];
uint8_t mysql_server_capabilities_two[2];
uint8_t mysql_server_language = 8;
uint8_t mysql_server_status[2];
uint8_t mysql_scramble_len = 21;
uint8_t mysql_filler_ten[10];
uint8_t mysql_last_byte = 0x00;
char server_scramble[GW_MYSQL_SCRAMBLE_SIZE + 1]="";
char *version_string;
int len_version_string=0;
MySQLProtocol *protocol = DCB_PROTOCOL(dcb, MySQLProtocol);
GWBUF *buf;
/* get the version string from service property if available*/
if (dcb->service->version_string != NULL) {
version_string = dcb->service->version_string;
len_version_string = strlen(version_string);
} else {
version_string = GW_MYSQL_VERSION;
len_version_string = strlen(GW_MYSQL_VERSION);
}
gw_generate_random_str(server_scramble, GW_MYSQL_SCRAMBLE_SIZE);
// copy back to the caller
memcpy(protocol->scramble, server_scramble, GW_MYSQL_SCRAMBLE_SIZE);
// fill the handshake packet
memset(&mysql_filler_ten, 0x00, sizeof(mysql_filler_ten));
// thread id, now put thePID
gw_mysql_set_byte4(mysql_thread_id, getpid() + dcb->fd);
memcpy(mysql_scramble_buf, server_scramble, 8);
memcpy(mysql_plugin_data, server_scramble + 8, 12);
mysql_payload_size = sizeof(mysql_protocol_version) + (len_version_string + 1) + sizeof(mysql_thread_id) + 8 + sizeof(mysql_filler) + sizeof(mysql_server_capabilities_one) + sizeof(mysql_server_language) + sizeof(mysql_server_status) + sizeof(mysql_server_capabilities_two) + sizeof(mysql_scramble_len) + sizeof(mysql_filler_ten) + 12 + sizeof(mysql_last_byte) + strlen("mysql_native_password") + sizeof(mysql_last_byte);
// allocate memory for packet header + payload
if ((buf = gwbuf_alloc(sizeof(mysql_packet_header) + mysql_payload_size)) == NULL)
{
ss_dassert(buf != NULL);
return 0;
}
outbuf = GWBUF_DATA(buf);
// write packet heder with mysql_payload_size
gw_mysql_set_byte3(mysql_packet_header, mysql_payload_size);
//mysql_packet_header[0] = mysql_payload_size;
// write packent number, now is 0
mysql_packet_header[3]= mysql_packet_id;
memcpy(outbuf, mysql_packet_header, sizeof(mysql_packet_header));
// current buffer pointer
mysql_handshake_payload = outbuf + sizeof(mysql_packet_header);
// write protocol version
memcpy(mysql_handshake_payload, &mysql_protocol_version, sizeof(mysql_protocol_version));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_protocol_version);
// write server version plus 0 filler
strcpy((char *)mysql_handshake_payload, version_string);
mysql_handshake_payload = mysql_handshake_payload + len_version_string;
*mysql_handshake_payload = 0x00;
mysql_handshake_payload++;
// write thread id
memcpy(mysql_handshake_payload, mysql_thread_id, sizeof(mysql_thread_id));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_thread_id);
// write scramble buf
memcpy(mysql_handshake_payload, mysql_scramble_buf, 8);
mysql_handshake_payload = mysql_handshake_payload + 8;
*mysql_handshake_payload = GW_MYSQL_HANDSHAKE_FILLER;
mysql_handshake_payload++;
// write server capabilities part one
mysql_server_capabilities_one[0] = GW_MYSQL_SERVER_CAPABILITIES_BYTE1;
mysql_server_capabilities_one[1] = GW_MYSQL_SERVER_CAPABILITIES_BYTE2;
mysql_server_capabilities_one[0] &= ~GW_MYSQL_CAPABILITIES_COMPRESS;
mysql_server_capabilities_one[0] &= ~GW_MYSQL_CAPABILITIES_SSL;
memcpy(mysql_handshake_payload, mysql_server_capabilities_one, sizeof(mysql_server_capabilities_one));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_server_capabilities_one);
// write server language
memcpy(mysql_handshake_payload, &mysql_server_language, sizeof(mysql_server_language));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_server_language);
//write server status
mysql_server_status[0] = 2;
mysql_server_status[1] = 0;
memcpy(mysql_handshake_payload, mysql_server_status, sizeof(mysql_server_status));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_server_status);
//write server capabilities part two
mysql_server_capabilities_two[0] = 15;
mysql_server_capabilities_two[1] = 128;
memcpy(mysql_handshake_payload, mysql_server_capabilities_two, sizeof(mysql_server_capabilities_two));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_server_capabilities_two);
// write scramble_len
memcpy(mysql_handshake_payload, &mysql_scramble_len, sizeof(mysql_scramble_len));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_scramble_len);
//write 10 filler
memcpy(mysql_handshake_payload, mysql_filler_ten, sizeof(mysql_filler_ten));
mysql_handshake_payload = mysql_handshake_payload + sizeof(mysql_filler_ten);
// write plugin data
memcpy(mysql_handshake_payload, mysql_plugin_data, 12);
mysql_handshake_payload = mysql_handshake_payload + 12;
//write last byte, 0
*mysql_handshake_payload = 0x00;
mysql_handshake_payload++;
// to be understanded ????
memcpy(mysql_handshake_payload, "mysql_native_password", strlen("mysql_native_password"));
mysql_handshake_payload = mysql_handshake_payload + strlen("mysql_native_password");
//write last byte, 0
*mysql_handshake_payload = 0x00;
mysql_handshake_payload++;
// writing data in the Client buffer queue
dcb->func.write(dcb, buf);
return sizeof(mysql_packet_header) + mysql_payload_size;
}
/**
* gw_mysql_do_authentication
*
* Performs the MySQL protocol 4.1 authentication, using data in GWBUF *queue
*
* The useful data: user, db, client_sha1 are copied into the MYSQL_session * dcb->session->data
* client_capabilitiesa are copied into the dcb->protocol
*
* @param dcb Descriptor Control Block of the client
* @param queue The GWBUF with data from client
* @return 0 If succeed, otherwise non-zero value
*
*/
static int gw_mysql_do_authentication(DCB *dcb, GWBUF *queue) {
MySQLProtocol *protocol = NULL;
/* int compress = -1; */
int connect_with_db = -1;
uint8_t *client_auth_packet = GWBUF_DATA(queue);
int client_auth_packet_size = 0;
char *username = NULL;
char *database = NULL;
unsigned int auth_token_len = 0;
uint8_t *auth_token = NULL;
uint8_t *stage1_hash = NULL;
int auth_ret = -1;
MYSQL_session *client_data = NULL;
CHK_DCB(dcb);
protocol = DCB_PROTOCOL(dcb, MySQLProtocol);
CHK_PROTOCOL(protocol);
client_data = (MYSQL_session *)calloc(1, sizeof(MYSQL_session));
dcb->data = client_data;
stage1_hash = client_data->client_sha1;
username = client_data->user;
client_auth_packet_size = gwbuf_length(queue);
/* For clients supporting CLIENT_PROTOCOL_41
* the Handshake Response Packet is:
*
* 4 bytes mysql protocol heade
* 4 bytes capability flags
* 4 max-packet size
* 1 byte character set
* string[23] reserved (all [0])
* ...
* ...
*/
/* Detect now if there are enough bytes to continue */
if (client_auth_packet_size < (4 + 4 + 4 + 1 + 23)) {
return 1;
}
memcpy(&protocol->client_capabilities, client_auth_packet + 4, 4);
connect_with_db =
GW_MYSQL_CAPABILITIES_CONNECT_WITH_DB & gw_mysql_get_byte4(
(uint32_t *)&protocol->client_capabilities);
/*
compress =
GW_MYSQL_CAPABILITIES_COMPRESS & gw_mysql_get_byte4(
&protocol->client_capabilities);
*/
username = get_username_from_auth(username, client_auth_packet);
if (username == NULL)
{
return 1;
}
/* get the auth token len */
memcpy(&auth_token_len,
client_auth_packet + 4 + 4 + 4 + 1 + 23 + strlen(username) + 1,
1);
/*
* Note: some clients may pass empty database, connect_with_db !=0 but database =""
*/
if (connect_with_db) {
database = client_data->db;
strncpy(database,
(char *)(client_auth_packet + 4 + 4 + 4 + 1 + 23 + strlen(username) +
1 + 1 + auth_token_len), MYSQL_DATABASE_MAXLEN);
}
/* allocate memory for token only if auth_token_len > 0 */
if (auth_token_len) {
auth_token = (uint8_t *)malloc(auth_token_len);
memcpy(auth_token,
client_auth_packet + 4 + 4 + 4 + 1 + 23 + strlen(username) + 1 + 1,
auth_token_len);
}
/*
* Decode the token and check the password
* Note: if auth_token_len == 0 && auth_token == NULL, user is without password
*/
auth_ret = gw_check_mysql_scramble_data(dcb,
auth_token,
auth_token_len,
protocol->scramble, sizeof(protocol->scramble),
username,
stage1_hash);
/* check for database name match in resource hashtable */
auth_ret = check_db_name_after_auth(dcb, database, auth_ret);
/* On failed auth try to load users' table from backend database */
if (auth_ret != 0) {
if (!service_refresh_users(dcb->service)) {
/* Try authentication again with new repository data */
/* Note: if no auth client authentication will fail */
auth_ret = gw_check_mysql_scramble_data(dcb, auth_token, auth_token_len, protocol->scramble, sizeof(protocol->scramble), username, stage1_hash);
}
}
/* Do again the database check */
auth_ret = check_db_name_after_auth(dcb, database, auth_ret);
/* on succesful auth set user into dcb field */
if (auth_ret == 0) {
dcb->user = strdup(client_data->user);
}
/* let's free the auth_token now */
if (auth_token) {
free(auth_token);
}
return auth_ret;
}
/**
* Write function for client DCB: writes data from MaxScale to Client
*
* @param dcb The DCB of the client
* @param queue Queue of buffers to write
*/
int
gw_MySQLWrite_client(DCB *dcb, GWBUF *queue)
{
return dcb_write(dcb, queue);
}
/**
* Client read event triggered by EPOLLIN
*
* @param dcb Descriptor control block
* @return 0 if succeed, 1 otherwise
*/
int gw_read_client_event(
DCB* dcb)
{
SESSION *session = NULL;
ROUTER_OBJECT *router = NULL;
ROUTER *router_instance = NULL;
void *rsession = NULL;
MySQLProtocol *protocol = NULL;
GWBUF *read_buffer = NULL;
int rc = 0;
int nbytes_read = 0;
CHK_DCB(dcb);
protocol = DCB_PROTOCOL(dcb, MySQLProtocol);
CHK_PROTOCOL(protocol);
rc = dcb_read(dcb, &read_buffer);
if (rc < 0)
{
dcb_close(dcb);
}
nbytes_read = gwbuf_length(read_buffer);
if (nbytes_read == 0)
{
goto return_rc;
}
/**
* if read queue existed appent read to it.
* if length of read buffer is less than 3 or less than mysql packet
* then return.
* else copy mysql packets to separate buffers from read buffer and
* continue.
* else
* if read queue didn't exist, length of read is less than 3 or less
* than mysql packet then
* create read queue and append to it and return.
* if length read is less than mysql packet length append to read queue
* append to it and return.
* else (complete packet was read) continue.
*/
if (dcb->dcb_readqueue)
{
uint8_t* data;
dcb->dcb_readqueue = gwbuf_append(dcb->dcb_readqueue, read_buffer);
nbytes_read = gwbuf_length(dcb->dcb_readqueue);
data = (uint8_t *)GWBUF_DATA(dcb->dcb_readqueue);
if (nbytes_read < 3 || nbytes_read < MYSQL_GET_PACKET_LEN(data))
{
rc = 0;
goto return_rc;
}
else
{
/**
* There is at least one complete mysql packet in
* read_buffer.
*/
read_buffer = dcb->dcb_readqueue;
dcb->dcb_readqueue = NULL;
}
}
else
{
uint8_t* data = (uint8_t *)GWBUF_DATA(read_buffer);
if (nbytes_read < 3 || nbytes_read < MYSQL_GET_PACKET_LEN(data)+4)
{
dcb->dcb_readqueue = gwbuf_append(dcb->dcb_readqueue, read_buffer);
rc = 0;
goto return_rc;
}
}
/**
* Now there should be at least one complete mysql packet in read_buffer.
*/
switch (protocol->protocol_auth_state) {
case MYSQL_AUTH_SENT:
{
int auth_val;
auth_val = gw_mysql_do_authentication(dcb, read_buffer);
if (auth_val == 0)
{
SESSION *session;
protocol->protocol_auth_state = MYSQL_AUTH_RECV;
/**
* Create session, and a router session for it.
* If successful, there will be backend connection(s)
* after this point.
*/
session = session_alloc(dcb->service, dcb);
if (session != NULL)
{
CHK_SESSION(session);
ss_dassert(session->state != SESSION_STATE_ALLOC);
protocol->protocol_auth_state = MYSQL_IDLE;
/**
* Send an AUTH_OK packet to the client,
* packet sequence is # 2
*/
mysql_send_ok(dcb, 2, 0, NULL);
}
else
{
protocol->protocol_auth_state = MYSQL_AUTH_FAILED;
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_read_client_event] session "
"creation failed. fd %d, "
"state = MYSQL_AUTH_FAILED.",
protocol->owner_dcb->fd,
pthread_self())));
/** Send ERR 1045 to client */
mysql_send_auth_error(
dcb,
2,
0,
"failed to create new session");
dcb_close(dcb);
}
}
else
{
char* fail_str = NULL;
protocol->protocol_auth_state = MYSQL_AUTH_FAILED;
if (auth_val == 2) {
/** Send error 1049 to client */
int message_len = 25 + MYSQL_DATABASE_MAXLEN;
fail_str = calloc(1, message_len+1);
snprintf(fail_str, message_len, "Unknown database '%s'", (char*)((MYSQL_session *)dcb->data)->db);
modutil_send_mysql_err_packet(dcb, 2, 0, 1049, "42000", fail_str);
} else {
/** Send error 1045 to client */
fail_str = create_auth_fail_str((char *)((MYSQL_session *)dcb->data)->user,
dcb->remote,
(char*)((MYSQL_session *)dcb->data)->client_sha1,
(char*)((MYSQL_session *)dcb->data)->db);
modutil_send_mysql_err_packet(dcb, 2, 0, 1045, "28000", fail_str);
}
if (fail_str)
free(fail_str);
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_read_client_event] after "
"gw_mysql_do_authentication, fd %d, "
"state = MYSQL_AUTH_FAILED.",
protocol->owner_dcb->fd,
pthread_self())));
dcb_close(dcb);
}
read_buffer = gwbuf_consume(read_buffer, nbytes_read);
}
break;
case MYSQL_IDLE:
{
uint8_t cap = 0;
uint8_t* payload = NULL;
bool stmt_input; /*< router input type */
ss_dassert(nbytes_read >= 5);
session = dcb->session;
ss_dassert( session!= NULL);
if (session != NULL)
{
CHK_SESSION(session);
router = session->service->router;
router_instance =
session->service->router_instance;
rsession = session->router_session;
ss_dassert(rsession != NULL);
}
/* Now, we are assuming in the first buffer there is
* the information form mysql command */
payload = GWBUF_DATA(read_buffer);
/**
* Without rsession there is no access to backend.
* COM_QUIT : close client dcb
* else : write custom error to client dcb.
*/
if(rsession == NULL)
{
/** COM_QUIT */
if (MYSQL_IS_COM_QUIT(payload))
{
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"%lu [gw_read_client_event] Client read "
"COM_QUIT and rsession == NULL. Closing "
"client dcb %p.",
pthread_self(),
dcb)));
/**
* close router session and that closes
* backends
*/
dcb_close(dcb);
}
else
{
#if defined(SS_DEBUG)
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Client read error handling.")));
#endif
/* Send a custom error as MySQL command reply */
mysql_send_custom_error(
dcb,
1,
0,
"Can't route query. Connection to "
"backend lost");
}
rc = 1;
/** Free buffer */
read_buffer = gwbuf_consume(read_buffer, nbytes_read);
goto return_rc;
}
/** Ask what type of input the router expects */
cap = router->getCapabilities(router_instance, rsession);
if (cap == 0 || (cap == RCAP_TYPE_PACKET_INPUT))
{
stmt_input = false;
}
else if (cap == RCAP_TYPE_STMT_INPUT)
{
stmt_input = true;
/** Mark buffer to as MySQL type */
gwbuf_set_type(read_buffer, GWBUF_TYPE_MYSQL);
}
else
{
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"%lu [gw_read_client_event] Reading router "
"capabilities failed.",
pthread_self())));
mysql_send_custom_error(dcb,
1,
0,
"Operation failed. Router "
"session is closed.");
rc = 1;
goto return_rc;
}
/** Route COM_QUIT to backend */
if (MYSQL_IS_COM_QUIT(payload))
{
/**
* Sends COM_QUIT packets since buffer is already
* created. A BREF_CLOSED flag is set so dcb_close won't
* send redundant COM_QUIT.
*/
SESSION_ROUTE_QUERY(session, read_buffer);
/**
* Close router session which causes closing of backends.
*/
dcb_close(dcb);
}
else
{
if (stmt_input)
{
/**
* Feed each statement completely and separately
* to router.
*/
rc = route_by_statement(session, &read_buffer);
if (read_buffer != NULL)
{
/** add incomplete mysql packet to read queue */
dcb->dcb_readqueue = gwbuf_append(dcb->dcb_readqueue, read_buffer);
}
}
else
{
/** Feed whole packet to router */
rc = SESSION_ROUTE_QUERY(session, read_buffer);
}
/** succeed */
if (rc)
{
rc = 0; /**< here '0' means success */
}
else
{
GWBUF* errbuf;
bool succp;
modutil_send_mysql_err_packet(dcb,
1,
0,
2003,
"HY000",
"Write to backend failed. Session closed.");
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Routing the query failed. "
"Session will be closed.")));
dcb_close(dcb);
}
}
goto return_rc;
} /* MYSQL_IDLE */
break;
default:
break;
}
rc = 0;
return_rc:
#if defined(SS_DEBUG)
if (dcb->state == DCB_STATE_POLLING ||
dcb->state == DCB_STATE_NOPOLLING ||
dcb->state == DCB_STATE_ZOMBIE)
{
CHK_PROTOCOL(protocol);
}
#endif
return rc;
}
///////////////////////////////////////////////
// client write event to Client triggered by EPOLLOUT
//////////////////////////////////////////////
/**
* @node Client's fd became writable, and EPOLLOUT event
* arrived. As a consequence, client input buffer (writeq) is flushed.
*
* Parameters:
* @param dcb - in, use
* client dcb
*
* @return constantly 1
*
*
* @details (write detailed description here)
*
*/
int gw_write_client_event(DCB *dcb)
{
MySQLProtocol *protocol = NULL;
CHK_DCB(dcb);
ss_dassert(dcb->state != DCB_STATE_DISCONNECTED);
if (dcb == NULL) {
goto return_1;
}
if (dcb->state == DCB_STATE_DISCONNECTED) {
goto return_1;
}
if (dcb->protocol == NULL) {
goto return_1;
}
protocol = (MySQLProtocol *)dcb->protocol;
CHK_PROTOCOL(protocol);
if (protocol->protocol_auth_state == MYSQL_IDLE)
{
dcb_drain_writeq(dcb);
goto return_1;
}
return_1:
#if defined(SS_DEBUG)
if (dcb->state == DCB_STATE_POLLING ||
dcb->state == DCB_STATE_NOPOLLING ||
dcb->state == DCB_STATE_ZOMBIE)
{
CHK_PROTOCOL(protocol);
}
#endif
return 1;
}
/**
* set listener for mysql protocol, retur 1 on success and 0 in failure
*/
int gw_MySQLListener(
DCB *listen_dcb,
char *config_bind)
{
int l_so;
struct sockaddr_in serv_addr;
struct sockaddr_un local_addr;
struct sockaddr *current_addr;
int one = 1;
int rc;
if (strchr(config_bind, '/')) {
char *tmp = strrchr(config_bind, ':');
if (tmp)
*tmp = '\0';
// UNIX socket create
if ((l_so = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
fprintf(stderr,
"\n* Error: can't create UNIX socket due "
"error %i, %s.\n\n\t",
errno,
strerror(errno));
return 0;
}
memset(&local_addr, 0, sizeof(local_addr));
local_addr.sun_family = AF_UNIX;
strncpy(local_addr.sun_path, config_bind, sizeof(local_addr.sun_path) - 1);
current_addr = (struct sockaddr *) &local_addr;
} else {
/* MaxScale, as default, will bind on port 4406 */
if (!parse_bindconfig(config_bind, 4406, &serv_addr)) {
fprintf(stderr, "Error in parse_bindconfig for [%s]\n", config_bind);
return 0;
}
// TCP socket create
if ((l_so = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
fprintf(stderr,
"\n* Error: can't create socket due "
"error %i, %s.\n\n\t",
errno,
strerror(errno));
return 0;
}
current_addr = (struct sockaddr *) &serv_addr;
}
listen_dcb->fd = -1;
// socket options
setsockopt(l_so, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof(one));
// set NONBLOCKING mode
setnonblocking(l_so);
/* get the right socket family for bind */
switch (current_addr->sa_family) {
case AF_UNIX:
rc = unlink(config_bind);
if ( (rc == -1) && (errno!=ENOENT) ) {
fprintf(stderr, "Error unlink Unix Socket %s\n", config_bind);
}
if (bind(l_so, (struct sockaddr *) &local_addr, sizeof(local_addr)) < 0) {
fprintf(stderr,
"\n* Bind failed due error %i, %s.\n",
errno,
strerror(errno));
fprintf(stderr, "* Can't bind to %s\n\n", config_bind);
close(l_so);
return 0;
}
/* set permission for all users */
if (chmod(config_bind, 0777) < 0) {
fprintf(stderr,
"\n* chmod failed for %s due error %i, %s.\n\n",
config_bind,
errno,
strerror(errno));
}
break;
case AF_INET:
if (bind(l_so, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
fprintf(stderr,
"\n* Bind failed due error %i, %s.\n",
errno,
strerror(errno));
fprintf(stderr, "* Can't bind to %s\n\n", config_bind);
close(l_so);
return 0;
}
break;
default:
fprintf(stderr, "* Socket Family %i not supported\n", current_addr->sa_family);
close(l_so);
return 0;
}
rc = listen(l_so, 10 * SOMAXCONN);
if (rc == 0) {
fprintf(stderr,
"Listening MySQL connections at %s\n",
config_bind);
} else {
int eno = errno;
errno = 0;
fprintf(stderr,
"\n* Failed to start listening MySQL due error %d, %s\n\n",
eno,
strerror(eno));
close(l_so);
return 0;
}
// assign l_so to dcb
listen_dcb->fd = l_so;
// add listening socket to poll structure
if (poll_add_dcb(listen_dcb) == -1) {
fprintf(stderr,
"\n* Failed to start polling the socket due error "
"%i, %s.\n\n",
errno,
strerror(errno));
return 0;
}
#if defined(SS_DEBUG)
conn_open[l_so] = true;
#endif
listen_dcb->func.accept = gw_MySQLAccept;
return 1;
}
/**
* @node (write brief function description here)
*
* Parameters:
* @param listener - <usage>
* <description>
*
* @return 0 in success, 1 in failure
*
*
* @details (write detailed description here)
*
*/
int gw_MySQLAccept(DCB *listener)
{
int rc = 0;
DCB *client_dcb;
MySQLProtocol *protocol;
int c_sock;
struct sockaddr client_conn;
socklen_t client_len = sizeof(struct sockaddr_storage);
int sendbuf = GW_BACKEND_SO_SNDBUF;
socklen_t optlen = sizeof(sendbuf);
int eno = 0;
int i = 0;
CHK_DCB(listener);
while (1) {
retry_accept:
#if defined(SS_DEBUG)
if (fail_next_accept > 0)
{
c_sock = -1;
eno = fail_accept_errno;
fail_next_accept -= 1;
} else {
fail_accept_errno = 0;
#endif /* SS_DEBUG */
// new connection from client
c_sock = accept(listener->fd,
(struct sockaddr *) &client_conn,
&client_len);
eno = errno;
errno = 0;
#if defined(SS_DEBUG)
}
#endif /* SS_DEBUG */
if (c_sock == -1) {
if (eno == EAGAIN || eno == EWOULDBLOCK)
{
/**
* We have processed all incoming connections.
*/
rc = 1;
goto return_rc;
}
else if (eno == ENFILE || eno == EMFILE)
{
/**
* Exceeded system's (ENFILE) or processes
* (EMFILE) max. number of files limit.
*/
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_MySQLAccept] Error %d, %s. ",
pthread_self(),
eno,
strerror(eno))));
if (i == 0)
{
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error %d, %s. "
"Failed to accept new client "
"connection.",
eno,
strerror(eno))));
}
i++;
usleep(100*i*i);
if (i<10) {
goto retry_accept;
}
rc = 1;
goto return_rc;
}
else
{
/**
* Other error.
*/
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_MySQLAccept] Error %d, %s.",
pthread_self(),
eno,
strerror(eno))));
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Failed to accept new client "
"connection due to %d, %s.",
eno,
strerror(eno))));
rc = 1;
goto return_rc;
} /* if (eno == ..) */
} /* if (c_sock == -1) */
/* reset counter */
i = 0;
listener->stats.n_accepts++;
#if defined(SS_DEBUG)
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"%lu [gw_MySQLAccept] Accepted fd %d.",
pthread_self(),
c_sock)));
conn_open[c_sock] = true;
#endif
/* set nonblocking */
sendbuf = GW_CLIENT_SO_SNDBUF;
setsockopt(c_sock, SOL_SOCKET, SO_SNDBUF, &sendbuf, optlen);
sendbuf = GW_CLIENT_SO_RCVBUF;
setsockopt(c_sock, SOL_SOCKET, SO_RCVBUF, &sendbuf, optlen);
setnonblocking(c_sock);
client_dcb = dcb_alloc(DCB_ROLE_REQUEST_HANDLER);
if (client_dcb == NULL) {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Failed to create "
"DCB object for client connection.")));
close(c_sock);
rc = 1;
goto return_rc;
}
client_dcb->service = listener->session->service;
client_dcb->fd = c_sock;
// get client address
if ( client_conn.sa_family == AF_UNIX)
{
// client address
client_dcb->remote = strdup("localhost_from_socket");
// set localhost IP for user authentication
(client_dcb->ipv4).sin_addr.s_addr = 0x0100007F;
}
else
{
/* client IPv4 in raw data*/
memcpy(&client_dcb->ipv4,
(struct sockaddr_in *)&client_conn,
sizeof(struct sockaddr_in));
/* client IPv4 in string representation */
client_dcb->remote = (char *)calloc(INET_ADDRSTRLEN+1, sizeof(char));
if (client_dcb->remote != NULL)
{
inet_ntop(AF_INET,
&(client_dcb->ipv4).sin_addr,
client_dcb->remote,
INET_ADDRSTRLEN);
}
}
protocol = mysql_protocol_init(client_dcb, c_sock);
ss_dassert(protocol != NULL);
if (protocol == NULL) {
/** delete client_dcb */
dcb_close(client_dcb);
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"%lu [gw_MySQLAccept] Failed to create "
"protocol object for client connection.",
pthread_self())));
rc = 1;
goto return_rc;
}
client_dcb->protocol = protocol;
// assign function poiters to "func" field
memcpy(&client_dcb->func, &MyObject, sizeof(GWPROTOCOL));
//send handshake to the client_dcb
MySQLSendHandshake(client_dcb);
// client protocol state change
protocol->protocol_auth_state = MYSQL_AUTH_SENT;
/**
* Set new descriptor to event set. At the same time,
* change state to DCB_STATE_POLLING so that
* thread which wakes up sees correct state.
*/
if (poll_add_dcb(client_dcb) == -1)
{
/* Send a custom error as MySQL command reply */
mysql_send_custom_error(
client_dcb,
1,
0,
"MaxScale internal error.");
/** close client_dcb */
dcb_close(client_dcb);
/** Previous state is recovered in poll_add_dcb. */
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"%lu [gw_MySQLAccept] Failed to add dcb %p for "
"fd %d to epoll set.",
pthread_self(),
client_dcb,
client_dcb->fd)));
rc = 1;
goto return_rc;
}
else
{
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_MySQLAccept] Added dcb %p for fd "
"%d to epoll set.",
pthread_self(),
client_dcb,
client_dcb->fd)));
}
} /**< while 1 */
#if defined(SS_DEBUG)
if (rc == 0) {
CHK_DCB(client_dcb);
CHK_PROTOCOL(((MySQLProtocol *)client_dcb->protocol));
}
#endif
return_rc:
return rc;
}
static int gw_error_client_event(
DCB* dcb)
{
SESSION* session;
CHK_DCB(dcb);
session = dcb->session;
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_error_client_event] Error event handling for DCB %p "
"in state %s, session %p.",
pthread_self(),
dcb,
STRDCBSTATE(dcb->state),
(session != NULL ? session : NULL))));
if (session != NULL && session->state == SESSION_STATE_STOPPING)
{
goto retblock;
}
#if defined(SS_DEBUG)
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Client error event handling.")));
#endif
dcb_close(dcb);
retblock:
return 1;
}
static int
gw_client_close(DCB *dcb)
{
SESSION* session;
ROUTER_OBJECT* router;
void* router_instance;
void* rsession;
#if defined(SS_DEBUG)
MySQLProtocol* protocol = (MySQLProtocol *)dcb->protocol;
if (dcb->state == DCB_STATE_POLLING ||
dcb->state == DCB_STATE_NOPOLLING ||
dcb->state == DCB_STATE_ZOMBIE)
{
CHK_PROTOCOL(protocol);
}
#endif
mysql_protocol_done(dcb);
session = dcb->session;
/**
* session may be NULL if session_alloc failed.
* In that case, router session wasn't created.
*/
if (session != NULL)
{
CHK_SESSION(session);
spinlock_acquire(&session->ses_lock);
if (session->state != SESSION_STATE_STOPPING)
{
session->state = SESSION_STATE_STOPPING;
}
spinlock_release(&session->ses_lock);
router = session->service->router;
router_instance = session->service->router_instance;
rsession = session->router_session;
/** Close router session and all its connections */
router->closeSession(router_instance, rsession);
}
return 1;
}
/**
* Handle a hangup event on the client side descriptor.
*
* We simply close the DCB, this will propogate the closure to any
* backend descriptors and perform the session cleanup.
*
* @param dcb The DCB of the connection
*/
static int
gw_client_hangup_event(DCB *dcb)
{
SESSION* session;
CHK_DCB(dcb);
session = dcb->session;
if (session != NULL && session->state == SESSION_STATE_ROUTER_READY)
{
CHK_SESSION(session);
}
if (session != NULL && session->state == SESSION_STATE_STOPPING)
{
goto retblock;
}
#if defined(SS_DEBUG)
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Client hangup error handling.")));
#endif
dcb_close(dcb);
retblock:
return 1;
}
/**
* Detect if buffer includes partial mysql packet or multiple packets.
* Store partial packet to dcb_readqueue. Send complete packets one by one
* to router.
*
* It is assumed readbuf includes at least one complete packet.
* Return 1 in success. If the last packet is incomplete return success but
* leave incomplete packet to readbuf.
*/
static int route_by_statement(
SESSION* session,
GWBUF** p_readbuf)
{
int rc = -1;
GWBUF* packetbuf;
#if defined(SS_DEBUG)
GWBUF* tmpbuf;
tmpbuf = *p_readbuf;
while (tmpbuf != NULL)
{
ss_dassert(GWBUF_IS_TYPE_MYSQL(tmpbuf));
tmpbuf=tmpbuf->next;
}
#endif
do
{
ss_dassert(GWBUF_IS_TYPE_MYSQL((*p_readbuf)));
/**
* Collect incoming bytes to a buffer until complete packet has
* arrived and then return the buffer.
*/
packetbuf = gw_MySQL_get_next_packet(p_readbuf);
if (packetbuf != NULL)
{
CHK_GWBUF(packetbuf);
ss_dassert(GWBUF_IS_TYPE_MYSQL(packetbuf));
/**
* This means that buffer includes exactly one MySQL
* statement.
* backend func.write uses the information. MySQL backend
* protocol, for example, stores the command identifier
* to protocol structure. When some other thread reads
* the corresponding response the command tells how to
* handle response.
*
* Set it here instead of gw_read_client_event to make
* sure it is set to each (MySQL) packet.
*/
gwbuf_set_type(packetbuf, GWBUF_TYPE_SINGLE_STMT);
/** Route query */
rc = SESSION_ROUTE_QUERY(session, packetbuf);
}
else
{
rc = 1;
goto return_rc;
}
}
while (*p_readbuf != NULL);
return_rc:
return rc;
}
/**
* Create a character array including the query string.
* GWBUF given as input includes either one complete or partial query.
* Length of buffer is at most the query length+4 (length of packet header).
*/
#if defined(NOT_USED)
static char* gw_get_or_create_querystr (
void* data,
bool* new_allocation)
{
GWBUF* buf = (GWBUF *)data;
size_t buflen; /*< first gw buffer data length */
size_t packetlen; /*< length of mysql packet */
size_t querylen; /*< total buffer length-<length of type indicator> */
size_t nbytes_copied;
char* startpos; /*< first byte of query in gw buffer */
char* str; /*< resulting query string */
CHK_GWBUF(buf);
packetlen = MYSQL_GET_PACKET_LEN((uint8_t *)GWBUF_DATA(buf));
str = (char *)malloc(packetlen); /*< leave space for terminating null */
if (str == NULL)
{
goto return_str;
}
*new_allocation = true;
/**
* First buffer includes 4 bytes header and a type indicator byte.
*/
buflen = GWBUF_LENGTH(buf);
querylen = packetlen-1;
ss_dassert(buflen<=querylen+5); /*< 5 == header+type indicator */
startpos = (char *)GWBUF_DATA(buf)+5;
nbytes_copied = MIN(querylen, buflen-5);
memcpy(str, startpos, nbytes_copied);
memset(&str[querylen-1], 0, 1);
buf = gwbuf_consume(buf, querylen-1);
/**
* In case of multi-packet statement whole buffer consists of query
* string.
*/
while (buf != NULL)
{
buflen = GWBUF_LENGTH(buf);
memcpy(str+nbytes_copied, GWBUF_DATA(buf), buflen);
nbytes_copied += buflen;
buf = gwbuf_consume(buf, buflen);
}
ss_dassert(str[querylen-1] == 0);
return_str:
return str;
}
#endif