/************************************************************************
* NAME: fnet_telnet_send_cmd
*
* DESCRIPTION: Wrie command to the TX buffer.
************************************************************************/
static void fnet_telnet_send_cmd(struct fnet_telnet_session_if *session, char command, char option )
{
tx_buffer_write(session, (char)FNET_TELNET_CMD_IAC);
tx_buffer_write(session, command);
tx_buffer_write(session, option);
/* Send the command.*/
fnet_telnet_send(session);
FNET_DEBUG_TELNET("TELNET: Send option = %d", option);
}
/************************************************************************
* DESCRIPTION:
************************************************************************/
static void fnet_telnet_send(struct fnet_telnet_session_if *session)
{
fnet_int32_t res;
fnet_index_t tx_buffer_tail_index = 0u;
fnet_time_t timeout = fnet_timer_get_ticks();
/* Send all data in the buffer.*/
while((tx_buffer_tail_index != session->tx_buffer_head_index) && (session->state != FNET_TELNET_STATE_CLOSING))
{
if((res = fnet_socket_send(session->socket_foreign, &session->tx_buffer[tx_buffer_tail_index], (fnet_size_t)session->tx_buffer_head_index - tx_buffer_tail_index, 0u)) != FNET_ERR)
{
if(res) /* >0 */
{
/* Update buffer pointers. */
tx_buffer_tail_index += (fnet_index_t)res;
/* Reset timeout. */
timeout = fnet_timer_get_ticks();
}
else if( fnet_timer_get_interval(timeout, fnet_timer_get_ticks())
> (FNET_TELNET_WAIT_SEND_MS / FNET_TIMER_PERIOD_MS) ) /* Check timeout */
{
FNET_DEBUG_TELNET("TELNET:Send timeout.");
break; /* Time-out. */
}
else
{}
}
else /* Error.*/
{
FNET_DEBUG_TELNET("TELNET:Send error.");
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
}
/* Reset TX buffer index. */
session->tx_buffer_head_index = 0u;
}
/************************************************************************
* NAME: fnet_telnet_send
*
* DESCRIPTION:
************************************************************************/
static void fnet_telnet_send(struct fnet_telnet_session_if *session)
{
int res;
int tx_buffer_tail_index = 0;
unsigned long timeout = fnet_timer_ticks();
/* Send all data in the buffer.*/
while(tx_buffer_tail_index != session->tx_buffer_head_index)
{
if((res = send(session->socket_foreign, &session->tx_buffer[tx_buffer_tail_index], session->tx_buffer_head_index - tx_buffer_tail_index, 0)) != SOCKET_ERROR)
{
if(res) /* >0 */
{
/* Update buffer pointers. */
tx_buffer_tail_index += res;
/* Reset timeout. */
timeout = fnet_timer_ticks();
}
else if( fnet_timer_get_interval(timeout, fnet_timer_ticks())
> (FNET_TELNET_WAIT_SEND_MS / FNET_TIMER_PERIOD_MS) ) /* Check timeout */
{
FNET_DEBUG_TELNET("TELNET:Send timeout.");
break; /* Time-out. */
}
}
else /* Error.*/
{
FNET_DEBUG_TELNET("TELNET:Send error.");
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
break;
}
}
/* Reset TX buffer index. */
session->tx_buffer_head_index = 0;
}
/************************************************************************
* NAME: fnet_telnet_init
*
* DESCRIPTION: Initialization of the Telnet server.
*************************************************************************/
fnet_telnet_desc_t fnet_telnet_init( struct fnet_telnet_params *params )
{
struct sockaddr local_addr;
struct fnet_telnet_if *telnet_if = 0;
/* Socket options. */
const struct linger linger_option ={1, /*l_onoff*/
4 /*l_linger*/};
const unsigned long bufsize_option = FNET_CFG_TELNET_SOCKET_BUF_SIZE;
const int keepalive_option = 1;
const int keepcnt_option = FNET_TELNET_TCP_KEEPCNT;
const int keepintvl_option = FNET_TELNET_TCP_KEEPINTVL;
const int keepidle_option = FNET_TELNET_TCP_KEEPIDLE;
int i;
if(params == 0 )
{
FNET_DEBUG_TELNET("TELNET: Wrong init parameters.");
goto ERROR_1;
}
/* Try to find free Telnet server descriptor. */
#if (FNET_CFG_TELNET_MAX > 1)
{
int i;
for(i=0; i<FNET_CFG_TELNET_MAX; i++)
{
if(telnet_if_list[i].enabled == FNET_FALSE)
{
telnet_if = &telnet_if_list[i];
break;
}
}
}
#else
if(telnet_if_list[0].enabled == FNET_FALSE)
telnet_if = &telnet_if_list[0];
#endif
/* No free Telnet server descriptor. */
if(telnet_if == 0)
{
FNET_DEBUG_TELNET("TELNET: No free Telnet Server.");
goto ERROR_1;
}
local_addr = params->address;
if(local_addr.sa_port == 0)
local_addr.sa_port = FNET_CFG_TELNET_PORT; /* Aply the default port. */
if(local_addr.sa_family == AF_UNSPEC)
local_addr.sa_family = AF_SUPPORTED; /* Asign supported families.*/
/* Create listen socket */
if((telnet_if->socket_listen = socket(local_addr.sa_family, SOCK_STREAM, 0)) == SOCKET_INVALID)
{
FNET_DEBUG_TELNET("TELNET: Socket creation error.");
goto ERROR_1;
}
if(bind(telnet_if->socket_listen, (struct sockaddr *)(&local_addr), sizeof(local_addr)) == SOCKET_ERROR)
{
FNET_DEBUG_TELNET("TELNET: Socket bind error.");
goto ERROR_2;
}
/* Set socket options. */
if( /* Setup linger option. */
(setsockopt (telnet_if->socket_listen, SOL_SOCKET, SO_LINGER, (char *)&linger_option, sizeof(linger_option)) == SOCKET_ERROR) ||
/* Set socket buffer size. */
(setsockopt(telnet_if->socket_listen, SOL_SOCKET, SO_RCVBUF, (char *) &bufsize_option, sizeof(bufsize_option))== SOCKET_ERROR) ||
(setsockopt(telnet_if->socket_listen, SOL_SOCKET, SO_SNDBUF, (char *) &bufsize_option, sizeof(bufsize_option))== SOCKET_ERROR) ||
/* Enable keepalive_option option. */
(setsockopt (telnet_if->socket_listen, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive_option, sizeof(keepalive_option)) == SOCKET_ERROR) ||
/* Keepalive probe retransmit limit. */
(setsockopt (telnet_if->socket_listen, IPPROTO_TCP, TCP_KEEPCNT, (char *)&keepcnt_option, sizeof(keepcnt_option)) == SOCKET_ERROR) ||
/* Keepalive retransmit interval.*/
(setsockopt (telnet_if->socket_listen, IPPROTO_TCP, TCP_KEEPINTVL, (char *)&keepintvl_option, sizeof(keepintvl_option)) == SOCKET_ERROR) ||
/* Time between keepalive probes.*/
(setsockopt (telnet_if->socket_listen, IPPROTO_TCP, TCP_KEEPIDLE, (char *)&keepidle_option, sizeof(keepidle_option)) == SOCKET_ERROR)
)
{
FNET_DEBUG_TELNET("TELNET: Socket setsockopt() error.");
goto ERROR_2;
}
telnet_if->backlog = FNET_CFG_TELNET_SESSION_MAX;
if(listen(telnet_if->socket_listen, telnet_if->backlog) == SOCKET_ERROR)
{
FNET_DEBUG_TELNET("TELNET: Socket listen error.");
goto ERROR_2;
}
/* Register service. */
telnet_if->service_descriptor = fnet_poll_service_register(fnet_telnet_state_machine, (void *) telnet_if);
if(telnet_if->service_descriptor == (fnet_poll_desc_t)FNET_ERR)
{
FNET_DEBUG_TELNET("TELNET: Service registration error.");
goto ERROR_2;
}
for(i=0; i<FNET_CFG_TELNET_SESSION_MAX; i++)
{
struct fnet_telnet_session_if *session = &telnet_if->session[i];
/* Reset buffer pointers. Move it to init state. */
session->tx_buffer_head_index = 0;
session->rx_buffer_head = session->rx_buffer;
session->rx_buffer_tail = session->rx_buffer;
session->rx_buffer_end = &session->rx_buffer[FNET_TELNET_RX_BUFFER_SIZE];
/* Setup stream. */
session->stream.id = (long)(session);
session->stream.putchar = fnet_telnet_putchar;
session->stream.getchar = fnet_telnet_getchar;
session->stream.flush = fnet_telnet_flush;
/* Init shell. */
session->shell_params.shell = params->shell;
session->shell_params.cmd_line_buffer = session->cmd_line_buffer;
session->shell_params.cmd_line_buffer_size = sizeof(session->cmd_line_buffer);
session->shell_params.stream = &session->stream;
session->shell_params.echo = FNET_CFG_TELNET_SHELL_ECHO;
session->socket_foreign = SOCKET_INVALID;
session->state = FNET_TELNET_STATE_LISTENING;
}
telnet_if->session_active = FNET_NULL;
telnet_if->enabled = FNET_TRUE;
return (fnet_telnet_desc_t)telnet_if;
ERROR_2:
closesocket(telnet_if->socket_listen);
ERROR_1:
return (fnet_telnet_desc_t)FNET_ERR;
}
/************************************************************************
* NAME: fnet_telnet_state_machine
*
* DESCRIPTION: Telnet server state machine.
************************************************************************/
static void fnet_telnet_state_machine( void *telnet_if_p )
{
struct sockaddr foreign_addr;
int res;
struct fnet_telnet_if *telnet = (struct fnet_telnet_if *)telnet_if_p;
char rx_data[1];
int len;
int i;
struct fnet_telnet_session_if *session;
for(i=0; i<FNET_CFG_TELNET_SESSION_MAX; i++)
{
session = &telnet->session[i];
telnet->session_active = session;
do
{
switch(session->state)
{
/*---- LISTENING ------------------------------------------------*/
case FNET_TELNET_STATE_LISTENING:
len = sizeof(foreign_addr);
session->socket_foreign = accept(telnet->socket_listen, (struct sockaddr *) &foreign_addr, &len);
if(session->socket_foreign != SOCKET_INVALID)
{
#if FNET_CFG_DEBUG_TELNET
{
char ip_str[FNET_IP_ADDR_STR_SIZE];
fnet_inet_ntop(foreign_addr.sa_family, foreign_addr.sa_data, ip_str, sizeof(ip_str));
FNET_DEBUG_TELNET("\nTELNET: New connection: %s; Port: %d.", ip_str, fnet_ntohs(foreign_addr.sa_port));
}
#endif
/* Init Shell. */
session->shell_descriptor = fnet_shell_init(&session->shell_params);
if(session->shell_descriptor == FNET_ERR)
{
session->shell_descriptor = 0;
FNET_DEBUG_TELNET("TELNET: Shell Service registration error.");
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
else
{
listen(telnet->socket_listen, --telnet->backlog); /* Ignor other connections.*/
/* Reset TX timeout. */
session->state = FNET_TELNET_STATE_RECEIVING; /* => WAITING data */
}
}
break;
/*---- NORMAL -----------------------------------------------*/
case FNET_TELNET_STATE_RECEIVING:
if(rx_buffer_free_space(session)>0)
{
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
if(rx_data[0] == FNET_TELNET_CMD_IAC )
{
session->state = FNET_TELNET_STATE_IAC; /*=> Handle IAC */
}
else
{
rx_buffer_write (session, rx_data[0]);
}
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
}
break;
/*---- IAC -----------------------------------------------*/
case FNET_TELNET_STATE_IAC:
FNET_DEBUG_TELNET("TELNET: STATE_IAC");
if((res = recv(session->socket_foreign, rx_data, 1, 0) )!= SOCKET_ERROR)
{
if(res)
{
switch(rx_data[0])
{
case FNET_TELNET_CMD_WILL:
session->state = FNET_TELNET_STATE_DONT;
break;
case FNET_TELNET_CMD_DO:
session->state = FNET_TELNET_STATE_WONT;
break;
case FNET_TELNET_CMD_WONT:
case FNET_TELNET_CMD_DONT:
session->state = FNET_TELNET_STATE_SKIP ;
break;
case FNET_TELNET_CMD_IAC:
/*
the IAC need be doubled to be sent as data, and
the other 255 codes may be passed transparently.
*/
rx_buffer_write (session, rx_data[0]);
default:
session->state = FNET_TELNET_STATE_RECEIVING; /*=> Ignore commands */
}
}
}
else
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
break;
/*---- DONT & WONT -----------------------------------------------*/
case FNET_TELNET_STATE_DONT:
case FNET_TELNET_STATE_WONT:
{
char command;
if(session->state == FNET_TELNET_STATE_DONT)
{
FNET_DEBUG_TELNET("TELNET: STATE_DONT");
command = FNET_TELNET_CMD_DONT;
}
else
{
FNET_DEBUG_TELNET("TELNET: STATE_WONT");
command = FNET_TELNET_CMD_WONT;
}
if(tx_buffer_free_space(session) >= 3)
{
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
/* Send command. */
fnet_telnet_send_cmd(session, command, rx_data[0]);
session->state = FNET_TELNET_STATE_RECEIVING;
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
}
}
break;
/*---- SKIP -----------------------------------------------*/
case FNET_TELNET_STATE_SKIP:
FNET_DEBUG_TELNET("TELNET: STATE_SKIP");
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
session->state = FNET_TELNET_STATE_RECEIVING;
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
break;
/*---- CLOSING --------------------------------------------*/
case FNET_TELNET_STATE_CLOSING:
FNET_DEBUG_TELNET("TELNET: STATE_CLOSING");
if(session->shell_descriptor)
{
fnet_shell_release(session->shell_descriptor);
session->shell_descriptor = 0;
}
session->rx_buffer_head = session->rx_buffer;
session->rx_buffer_tail = session->rx_buffer;
closesocket(session->socket_foreign);
session->socket_foreign = SOCKET_INVALID;
listen(telnet->socket_listen, ++telnet->backlog); /* Allow connection.*/
session->state = FNET_TELNET_STATE_LISTENING; /*=> LISTENING */
break;
default:
break;
}
}
while(session->state == FNET_TELNET_STATE_CLOSING);
}
}
