/*
* Process IAC DONT <option>.
*/
static void
telnet_dont(telnet_t *tp, u_char opt)
{
opt_t *op;
op = telnet_get_optp(tp, opt);
if (op == NULL)
return;
switch (op->o_us)
{
case OS_NO:
break;
case OS_YES:
op->o_us = OS_NO;
telnet_send_wont(tp, opt);
telnet_ack_ldisab(tp, opt);
break;
case OS_WANTNO:
switch (op->o_usq)
{
case OQ_EMPTY:
op->o_us = OS_NO;
telnet_ack_ldisab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_us = OS_WANTYES;
op->o_usq = OQ_EMPTY;
telnet_send_will(tp, opt);
break;
}
break;
case OS_WANTYES:
switch (op->o_usq)
{
case OQ_EMPTY:
op->o_us = OS_NO;
telnet_ack_ldisab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_us = OS_NO;
op->o_usq = OQ_EMPTY;
telnet_ack_ldisab(tp, opt);
break;
}
break;
}
}
/*
* Negotiate disabling an option in the remote-to-local direction.
*/
static void
telnet_neg_rdisab(telnet_t *tp, u_char opt)
{
opt_t *op;
op = telnet_get_optp(tp, opt);
if (op == NULL)
return;
switch (op->o_him)
{
case OS_NO:
break;
case OS_YES:
op->o_him = OS_WANTNO;
telnet_send_dont(tp, opt);
break;
case OS_WANTNO:
switch (op->o_himq)
{
case OQ_EMPTY:
break;
case OQ_OPPOSITE:
op->o_himq = OQ_EMPTY;
break;
}
break;
case OS_WANTYES:
switch (op->o_himq)
{
case OQ_EMPTY:
op->o_himq = OQ_OPPOSITE;
break;
case OQ_OPPOSITE:
break;
}
break;
}
}
/*
* Process IAC DO <option>.
*/
static void
telnet_do(telnet_t *tp, u_char opt)
{
opt_t *op;
if (opt == TELOPT_TM)
{
telnet_send_will(tp, opt);
return;
}
op = telnet_get_optp(tp, opt);
if (op == NULL)
{
telnet_send_wont(tp, opt);
return;
}
switch (op->o_us)
{
case OS_NO:
if (telnet_lenabp(tp, opt))
{
op->o_us = OS_YES;
telnet_send_will(tp, opt);
telnet_ack_lenab(tp, opt);
}
else
{
telnet_send_wont(tp, opt);
}
break;
case OS_YES:
break;
case OS_WANTNO:
switch (op->o_usq)
{
case OQ_EMPTY:
op->o_us = OS_NO;
telnet_ack_ldisab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_us = OS_YES;
op->o_usq = OQ_EMPTY;
telnet_ack_lenab(tp, opt);
break;
}
break;
case OS_WANTYES:
switch (op->o_usq)
{
case OQ_EMPTY:
op->o_us = OS_YES;
telnet_ack_lenab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_us = OS_WANTNO;
op->o_usq = OQ_EMPTY;
telnet_send_wont(tp, opt);
}
break;
}
}
/*
* Process IAC WILL <option>.
*/
static void
telnet_will(telnet_t *tp, u_char opt)
{
opt_t *op;
op = telnet_get_optp(tp, opt);
if (op == NULL)
{
telnet_send_dont(tp, opt);
return;
}
switch (op->o_him)
{
case OS_NO:
if (telnet_renabp(tp, opt))
{
op->o_him = OS_YES;
telnet_send_do(tp, opt);
telnet_ack_renab(tp, opt);
}
else
{
telnet_send_dont(tp, opt);
}
break;
case OS_YES:
break;
case OS_WANTNO:
switch (op->o_himq)
{
case OQ_EMPTY:
op->o_him = OS_NO;
telnet_ack_rdisab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_him = OS_YES;
op->o_himq = OQ_EMPTY;
telnet_ack_renab(tp, opt);
break;
}
break;
case OS_WANTYES:
switch (op->o_himq)
{
case OQ_EMPTY:
op->o_him = OS_YES;
telnet_ack_renab(tp, opt);
break;
case OQ_OPPOSITE:
op->o_him = OS_WANTNO;
op->o_himq = OQ_EMPTY;
telnet_send_dont(tp, opt);
}
break;
}
}
