/**
* Consume data from a buffer in the linked list. The assumption is to consume
* n bytes from the buffer chain.
*
* If after consuming the bytes from the first buffer that buffer becomes
* empty it will be freed and the linked list updated.
*
* The return value is the new head of the linked list.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The head of the linked list
* @param length The amount of data to consume
* @return The head of the linked list
*/
GWBUF *
gwbuf_consume(GWBUF *head, unsigned int length)
{
GWBUF *rval = head;
CHK_GWBUF(head);
GWBUF_CONSUME(head, length);
CHK_GWBUF(head);
if (GWBUF_EMPTY(head))
{
rval = head->next;
gwbuf_free(head);
}
return rval;
}
/**
* Consume data from a buffer in the linked list. The assumption is to consume
* n bytes from the buffer chain.
*
* If after consuming the bytes from the first buffer that buffer becomes
* empty it will be freed and the linked list updated.
*
* The return value is the new head of the linked list.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The head of the linked list
* @param length The amount of data to consume
* @return The head of the linked list
*/
GWBUF *
gwbuf_consume(GWBUF *head, unsigned int length)
{
GWBUF *rval = head;
CHK_GWBUF(head);
GWBUF_CONSUME(head, length);
CHK_GWBUF(head);
if (GWBUF_EMPTY(head))
{
rval = head->next;
if (head->next)
head->next->tail = head->tail;
gwbuf_free(head);
}
ss_dassert(rval == NULL || (rval->end > rval->start));
return rval;
}
/**
* 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;
}