/**
* Convert a chain of GWBUF structures into a single GWBUF structure
*
* @param orig The chain to convert
* @return The contiguous buffer
*/
GWBUF *
gwbuf_make_contiguous(GWBUF *orig)
{
GWBUF *newbuf;
char *ptr;
int len;
if (orig->next == NULL)
return orig;
if ((newbuf = gwbuf_alloc(gwbuf_length(orig))) != NULL)
{
newbuf->gwbuf_type = orig->gwbuf_type;
newbuf->hint = hint_dup(orig->hint);
ptr = GWBUF_DATA(newbuf);
while (orig)
{
len = GWBUF_LENGTH(orig);
memcpy(ptr, GWBUF_DATA(orig), len);
ptr += len;
orig = gwbuf_consume(orig, len);
}
}
return newbuf;
}
/**
* Trim bytes form the end of a GWBUF structure. If the
* buffer has n_bytes or less then it will be freed and
* NULL will be returned.
*
* This routine assumes the buffer is not part of a chain
*
* @param buf The buffer to trim
* @param n_bytes The number of bytes to trim off
* @return The buffer chain or NULL if buffer has <= n_bytes
*/
GWBUF *
gwbuf_trim(GWBUF *buf, unsigned int n_bytes)
{
ss_dassert(buf->next == NULL);
if (GWBUF_LENGTH(buf) <= n_bytes)
{
gwbuf_consume(buf, GWBUF_LENGTH(buf));
return NULL;
}
buf->end = (void *)((char *)buf->end - n_bytes);
return buf;
}
/**
* We have data from the client, we must route it to the backend.
* This is simply a case of sending it to the connection that was
* chosen when we started the client session.
*
* @param instance The router instance
* @param router_session The router session returned from the newSession call
* @param queue The queue of data buffers to route
* @return The number of bytes sent
*/
static int
execute(ROUTER *instance, void *router_session, GWBUF *queue)
{
CLI_SESSION *session = (CLI_SESSION *)router_session;
/* Extract the characters */
while (queue)
{
strncat(session->cmdbuf, GWBUF_DATA(queue), MIN(GWBUF_LENGTH(queue),cmdbuflen-1));
queue = gwbuf_consume(queue, GWBUF_LENGTH(queue));
}
execute_cmd(session);
return 1;
}
/**
* Process a request packet from the slave server.
*
* The router can handle a limited subset of requests from the slave, these
* include a subset of general SQL queries, a slave registeration command and
* the binlog dump command.
*
* The strategy for responding to these commands is to use caches responses
* for the the same commands that have previously been made to the real master
* if this is possible, if it is not then the router itself will synthesize a
* response.
*
* @param router The router instance this defines the master for this replication chain
* @param slave The slave specific data
* @param queue The incoming request packet
*/
int
blr_slave_request(ROUTER_INSTANCE *router, ROUTER_SLAVE *slave, GWBUF *queue)
{
if (slave->state < 0 || slave->state > BLRS_MAXSTATE)
{
LOGIF(LE, (skygw_log_write(
LOGFILE_ERROR, "Invalid slave state machine state (%d) for binlog router.",
slave->state)));
gwbuf_consume(queue, gwbuf_length(queue));
return 0;
}
slave->stats.n_requests++;
switch (MYSQL_COMMAND(queue))
{
case COM_QUERY:
return blr_slave_query(router, slave, queue);
break;
case COM_REGISTER_SLAVE:
return blr_slave_register(router, slave, queue);
break;
case COM_BINLOG_DUMP:
return blr_slave_binlog_dump(router, slave, queue);
break;
case COM_STATISTICS:
return blr_statistics(router, slave, queue);
break;
case COM_PING:
return blr_ping(router, slave, queue);
break;
case COM_QUIT:
LOGIF(LD, (skygw_log_write(LOGFILE_DEBUG,
"COM_QUIT received from slave with server_id %d",
slave->serverid)));
break;
default:
blr_send_custom_error(slave->dcb, 1, 0,
"MySQL command not supported by the binlog router.");
LOGIF(LE, (skygw_log_write(
LOGFILE_ERROR,
"Unexpected MySQL Command (%d) received from slave",
MYSQL_COMMAND(queue))));
break;
}
return 0;
}
/**
* Remove the first mysql statement from buffer. Return pointer to the removed
* statement or NULL if buffer is empty.
*
* Clone buf, calculate the length of included mysql stmt, and point the
* statement with cloned buffer. Move the start pointer of buf accordingly
* so that it only cover the remaining buffer.
*
*/
GWBUF* gw_MySQL_get_next_stmt(
GWBUF** p_readbuf)
{
GWBUF* stmtbuf;
size_t buflen;
size_t strlen;
uint8_t* packet;
if (*p_readbuf == NULL)
{
stmtbuf = NULL;
goto return_stmtbuf;
}
CHK_GWBUF(*p_readbuf);
if (GWBUF_EMPTY(*p_readbuf))
{
stmtbuf = NULL;
goto return_stmtbuf;
}
buflen = GWBUF_LENGTH((*p_readbuf));
packet = GWBUF_DATA((*p_readbuf));
strlen = MYSQL_GET_PACKET_LEN(packet);
if (strlen+4 == buflen)
{
stmtbuf = *p_readbuf;
*p_readbuf = NULL;
goto return_stmtbuf;
}
/** vraa :Multi-packet stmt is not supported as of 7.3.14 */
if (strlen-1 > buflen-5)
{
stmtbuf = NULL;
goto return_stmtbuf;
}
stmtbuf = gwbuf_clone_portion(*p_readbuf, 0, strlen+4);
*p_readbuf = gwbuf_consume(*p_readbuf, strlen+4);
return_stmtbuf:
return stmtbuf;
}
/**
* We have data from the client, we must route it to the backend.
* This is simply a case of sending it to the connection that was
* chosen when we started the client session.
*
* @param instance The router instance
* @param router_session The router session returned from the newSession call
* @param queue The queue of data buffers to route
* @return The number of bytes sent
*/
static int
execute(ROUTER *instance, void *router_session, GWBUF *queue)
{
CLI_SESSION *session = (CLI_SESSION *)router_session;
/* Extract the characters */
while (queue)
{
strncat(session->cmdbuf, GWBUF_DATA(queue), GWBUF_LENGTH(queue));
queue = gwbuf_consume(queue, GWBUF_LENGTH(queue));
}
if (strrchr(session->cmdbuf, '\n'))
{
if (execute_cmd(session))
dcb_printf(session->session->client, "MaxScale> ");
else
session->session->client->func.close(session->session->client);
}
return 1;
}
/**
* Read event for EPOLLIN on the telnetd protocol module.
*
* @param dcb The descriptor control block
* @return
*/
static int
telnetd_read_event(DCB* dcb)
{
int n;
GWBUF *head = NULL;
SESSION *session = dcb->session;
ROUTER_OBJECT *router = session->service->router;
ROUTER *router_instance = session->service->router_instance;
void *rsession = session->router_session;
TELNETD *telnetd = (TELNETD *)dcb->protocol;
char *password, *t;
if ((n = dcb_read(dcb, &head)) != -1)
{
if (head)
{
unsigned char *ptr = GWBUF_DATA(head);
ptr = GWBUF_DATA(head);
while (GWBUF_LENGTH(head) && *ptr == TELNET_IAC)
{
telnetd_command(dcb, ptr + 1);
GWBUF_CONSUME(head, 3);
ptr = GWBUF_DATA(head);
}
if (GWBUF_LENGTH(head))
{
switch (telnetd->state)
{
case TELNETD_STATE_LOGIN:
telnetd->username = strndup(GWBUF_DATA(head), GWBUF_LENGTH(head));
/* Strip the cr/lf from the username */
t = strstr(telnetd->username, "\r\n");
if (t)
*t = 0;
telnetd->state = TELNETD_STATE_PASSWD;
dcb_printf(dcb, "Password: "******"\r\n");
if (t)
*t = 0;
if (admin_verify(telnetd->username, password))
{
telnetd_echo(dcb, 1);
telnetd->state = TELNETD_STATE_DATA;
dcb_printf(dcb, "\n\nMaxScale> ");
}
else
{
dcb_printf(dcb, "\n\rLogin incorrect\n\rLogin: ");
telnetd_echo(dcb, 1);
telnetd->state = TELNETD_STATE_LOGIN;
free(telnetd->username);
}
gwbuf_consume(head, GWBUF_LENGTH(head));
free(password);
break;
case TELNETD_STATE_DATA:
router->routeQuery(router_instance, rsession, head);
break;
}
}
else
{
// Force the free of the buffer header
gwbuf_consume(head, 0);
}
}
}
return n;
}
/**
* Receive the MySQL authentication packet from backend, packet # is 2
*
* @param protocol The MySQL protocol structure
* @return -1 in case of failure, 0 if there was nothing to read, 1 if read
* was successful.
*/
int gw_receive_backend_auth(
MySQLProtocol *protocol)
{
int n = -1;
GWBUF *head = NULL;
DCB *dcb = protocol->owner_dcb;
uint8_t *ptr = NULL;
int rc = 0;
n = dcb_read(dcb, &head);
/*<
* Read didn't fail and there is enough data for mysql packet.
*/
if (n != -1 &&
head != NULL &&
GWBUF_LENGTH(head) >= 5)
{
ptr = GWBUF_DATA(head);
/*<
* 5th byte is 0x0 if successful.
*/
if (ptr[4] == '\x00') {
rc = 1;
} else {
uint8_t* tmpbuf =
(uint8_t *)calloc(1, GWBUF_LENGTH(head)+1);
memcpy(tmpbuf, ptr, GWBUF_LENGTH(head));
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_receive_backend_auth] Invalid "
"authentication message from backend dcb %p "
"fd %d, ptr[4] = %p, msg %s.",
pthread_self(),
dcb,
dcb->fd,
tmpbuf[4],
tmpbuf)));
free(tmpbuf);
rc = -1;
}
/*<
* Remove data from buffer.
*/
head = gwbuf_consume(head, GWBUF_LENGTH(head));
}
else if (n == 0)
{
/*<
* This is considered as success because call didn't fail,
* although no bytes was read.
*/
rc = 0;
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [gw_receive_backend_auth] Read zero bytes from "
"backend dcb %p fd %d in state %s. n %d, head %p, len %d",
pthread_self(),
dcb,
dcb->fd,
STRDCBSTATE(dcb->state),
n,
head,
(head == NULL) ? 0 : GWBUF_LENGTH(head))));
}
else
{
ss_dassert(n < 0 && head == NULL);
rc = -1;
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"%lu [gw_receive_backend_auth] Reading from backend dcb %p "
"fd %d in state %s failed. n %d, head %p, len %d",
pthread_self(),
dcb,
dcb->fd,
STRDCBSTATE(dcb->state),
n,
head,
(head == NULL) ? 0 : GWBUF_LENGTH(head))));
}
return rc;
}
/**
* Read the backend server MySQL handshake
*
* @param conn MySQL protocol structure
* @return 0 on success, 1 on failure
*/
int gw_read_backend_handshake(MySQLProtocol *conn) {
GWBUF *head = NULL;
DCB *dcb = conn->owner_dcb;
int n = -1;
uint8_t *payload = NULL;
int h_len = 0;
int success = 0;
int packet_len = 0;
if ((n = dcb_read(dcb, &head)) != -1) {
if (head) {
payload = GWBUF_DATA(head);
h_len = gwbuf_length(head);
/*
* The mysql packets content starts at byte fifth
* just return with less bytes
*/
if (h_len <= 4) {
/* log error this exit point */
conn->state = MYSQL_AUTH_FAILED;
return 1;
}
//get mysql packet size, 3 bytes
packet_len = gw_mysql_get_byte3(payload);
if (h_len < (packet_len + 4)) {
/*
* data in buffer less than expected in the
* packet. Log error this exit point
*/
conn->state = MYSQL_AUTH_FAILED;
return 1;
}
// skip the 4 bytes header
payload += 4;
//Now decode mysql handshake
success = gw_decode_mysql_server_handshake(conn,
payload);
if (success < 0) {
/* MySQL handshake has not been properly decoded
* we cannot continue
* log error this exit point
*/
conn->state = MYSQL_AUTH_FAILED;
return 1;
}
conn->state = MYSQL_AUTH_SENT;
// consume all the data here
head = gwbuf_consume(head, GWBUF_LENGTH(head));
return 0;
}
}
// Nothing done here, log error this
return 1;
}