static int
getterminaltype (void)
{
int retval = -1;
settimer(baseline);
send_do(TELOPT_TTYPE, 1);
send_do(TELOPT_TSPEED, 1);
send_do(TELOPT_XDISPLOC, 1);
send_do(TELOPT_ENVIRON, 1);
while (his_will_wont_is_changing(TELOPT_TTYPE) ||
his_will_wont_is_changing(TELOPT_TSPEED) ||
his_will_wont_is_changing(TELOPT_XDISPLOC) ||
his_will_wont_is_changing(TELOPT_ENVIRON)) {
ttloop();
}
if (his_state_is_will(TELOPT_TSPEED)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
memmove((void *)nfrontp, (void *)sb, sizeof sb);
nfrontp += sizeof sb;
DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
}
int
getterminaltype(char *name, size_t name_sz)
{
int retval = -1;
settimer(baseline);
#ifdef AUTHENTICATION
/*
* Handle the Authentication option before we do anything else.
*/
send_do(TELOPT_AUTHENTICATION, 1);
while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
ttloop();
if (his_state_is_will(TELOPT_AUTHENTICATION)) {
retval = auth_wait(name, name_sz);
}
#endif
#ifdef ENCRYPTION
send_will(TELOPT_ENCRYPT, 1);
send_do(TELOPT_ENCRYPT, 1); /* [email protected] */
#endif
/* DayDream wants binary transmission mode */
send_will(TELOPT_BINARY, 1);
send_do(TELOPT_BINARY, 1);
send_do(TELOPT_TTYPE, 1);
send_do(TELOPT_TSPEED, 1);
send_do(TELOPT_XDISPLOC, 1);
send_do(TELOPT_NEW_ENVIRON, 1);
send_do(TELOPT_OLD_ENVIRON, 1);
while (
#ifdef ENCRYPTION
his_do_dont_is_changing(TELOPT_ENCRYPT) ||
#endif
his_do_dont_is_changing(TELOPT_BINARY) ||
his_will_wont_is_changing(TELOPT_TTYPE) ||
his_will_wont_is_changing(TELOPT_TSPEED) ||
his_will_wont_is_changing(TELOPT_XDISPLOC) ||
his_will_wont_is_changing(TELOPT_NEW_ENVIRON) ||
his_will_wont_is_changing(TELOPT_OLD_ENVIRON)) {
ttloop();
}
#ifdef ENCRYPTION
/*
* Wait for the negotiation of what type of encryption we can
* send with. If autoencrypt is not set, this will just return.
*/
if (his_state_is_will(TELOPT_ENCRYPT)) {
encrypt_wait();
}
#endif
if (his_state_is_will(TELOPT_BINARY)) {
static unsigned char sb[] =
{ IAC, SB, TELOPT_BINARY, TELQUAL_SEND, IAC, SE };
telnet_net_write (sb, sizeof sb);
DIAG(TD_OPTIONS, printsub('>', sb + 2, sizeof sb - 2););
}
void
tel_enter_binary(int rw)
{
if (rw&1)
send_do(TELOPT_BINARY, 1);
if (rw&2)
send_will(TELOPT_BINARY, 1);
}
/*
* Select from tty and network...
*/
void
telnet(char *user)
{
connections++;
sys_telnet_init();
if (pledge("stdio rpath tty", NULL) == -1) {
perror("pledge");
exit(1);
}
if (telnetport) {
send_do(TELOPT_SGA, 1);
send_will(TELOPT_TTYPE, 1);
send_will(TELOPT_NAWS, 1);
send_will(TELOPT_TSPEED, 1);
send_will(TELOPT_LFLOW, 1);
send_will(TELOPT_LINEMODE, 1);
send_will(TELOPT_NEW_ENVIRON, 1);
send_do(TELOPT_STATUS, 1);
if (env_getvalue("DISPLAY", 0))
send_will(TELOPT_XDISPLOC, 1);
if (binary)
tel_enter_binary(binary);
}
for (;;) {
int schedValue;
while ((schedValue = Scheduler(0)) != 0) {
if (schedValue == -1) {
setcommandmode();
return;
}
}
if (Scheduler(1) == -1) {
setcommandmode();
return;
}
}
}
static void
willoption(int option)
{
int new_state_ok = 0;
if (do_dont_resp[option]) {
--do_dont_resp[option];
if (do_dont_resp[option] && my_state_is_do(option))
--do_dont_resp[option];
}
if ((do_dont_resp[option] == 0) && my_want_state_is_dont(option)) {
switch (option) {
case TELOPT_ECHO:
case TELOPT_BINARY:
case TELOPT_SGA:
settimer(modenegotiated);
/* FALL THROUGH */
case TELOPT_STATUS:
new_state_ok = 1;
break;
case TELOPT_TM:
if (flushout)
flushout = 0;
/*
* Special case for TM. If we get back a WILL,
* pretend we got back a WONT.
*/
set_my_want_state_dont(option);
set_my_state_dont(option);
return; /* Never reply to TM will's/wont's */
case TELOPT_LINEMODE:
default:
break;
}
if (new_state_ok) {
set_my_want_state_do(option);
send_do(option, 0);
setconnmode(0); /* possibly set new tty mode */
} else {
do_dont_resp[option]++;
send_dont(option, 0);
}
}
set_my_state_do(option);
}
static void
dooption(int option)
{
int new_state_ok = 0;
if (will_wont_resp[option]) {
--will_wont_resp[option];
if (will_wont_resp[option] && my_state_is_will(option))
--will_wont_resp[option];
}
if (will_wont_resp[option] == 0) {
if (my_want_state_is_wont(option)) {
switch (option) {
case TELOPT_TM:
/*
* Special case for TM. We send a WILL, but pretend
* we sent WONT.
*/
send_will(option, 0);
set_my_want_state_wont(TELOPT_TM);
set_my_state_wont(TELOPT_TM);
return;
case TELOPT_BINARY: /* binary mode */
case TELOPT_NAWS: /* window size */
case TELOPT_TSPEED: /* terminal speed */
case TELOPT_LFLOW: /* local flow control */
case TELOPT_TTYPE: /* terminal type option */
case TELOPT_SGA: /* no big deal */
#ifdef ENCRYPTION
case TELOPT_ENCRYPT: /* encryption variable option */
#endif /* ENCRYPTION */
new_state_ok = 1;
break;
case TELOPT_NEW_ENVIRON: /* New environment variable option */
#ifdef OLD_ENVIRON
if (my_state_is_will(TELOPT_OLD_ENVIRON))
send_wont(TELOPT_OLD_ENVIRON, 1); /* turn off the old */
goto env_common;
case TELOPT_OLD_ENVIRON: /* Old environment variable option */
if (my_state_is_will(TELOPT_NEW_ENVIRON))
break; /* Don't enable if new one is in use! */
env_common:
telopt_environ = option;
#endif
new_state_ok = 1;
break;
#ifdef AUTHENTICATION
case TELOPT_AUTHENTICATION:
if (autologin)
new_state_ok = 1;
break;
#endif
case TELOPT_XDISPLOC: /* X Display location */
if (env_getvalue("DISPLAY"))
new_state_ok = 1;
break;
case TELOPT_LINEMODE:
#ifdef KLUDGELINEMODE
kludgelinemode = 0;
send_do(TELOPT_SGA, 1);
#endif
set_my_want_state_will(TELOPT_LINEMODE);
send_will(option, 0);
set_my_state_will(TELOPT_LINEMODE);
slc_init();
return;
case TELOPT_ECHO: /* We're never going to echo... */
default:
break;
}
if (new_state_ok) {
set_my_want_state_will(option);
send_will(option, 0);
setconnmode(0); /* Set new tty mode */
} else {
will_wont_resp[option]++;
send_wont(option, 0);
}
} else {
/*
* Handle options that need more things done after the
* other side has acknowledged the option.
*/
switch (option) {
case TELOPT_LINEMODE:
#ifdef KLUDGELINEMODE
kludgelinemode = 0;
send_do(TELOPT_SGA, 1);
#endif
set_my_state_will(option);
slc_init();
send_do(TELOPT_SGA, 0);
return;
}
}
}
set_my_state_will(option);
}
/*
* Select from tty and network...
*/
void
my_telnet(char *user)
{
int printed_encrypt = 0;
sys_telnet_init();
#if defined(AUTHENTICATION) || defined(ENCRYPTION)
{
static char local_host[256] = { 0 };
if (!local_host[0]) {
/* XXX - should be k_gethostname? */
gethostname(local_host, sizeof(local_host));
local_host[sizeof(local_host)-1] = 0;
}
auth_encrypt_init(local_host, hostname, "TELNET", 0);
auth_encrypt_user(user);
}
#endif
if (telnetport) {
#if defined(AUTHENTICATION)
if (autologin)
send_will(TELOPT_AUTHENTICATION, 1);
#endif
#if defined(ENCRYPTION)
send_do(TELOPT_ENCRYPT, 1);
send_will(TELOPT_ENCRYPT, 1);
#endif
send_do(TELOPT_SGA, 1);
send_will(TELOPT_TTYPE, 1);
send_will(TELOPT_NAWS, 1);
send_will(TELOPT_TSPEED, 1);
send_will(TELOPT_LFLOW, 1);
send_will(TELOPT_LINEMODE, 1);
send_will(TELOPT_NEW_ENVIRON, 1);
send_do(TELOPT_STATUS, 1);
if (env_getvalue((unsigned char *)"DISPLAY"))
send_will(TELOPT_XDISPLOC, 1);
if (binary)
tel_enter_binary(binary);
}
#ifdef ENCRYPTION
/*
* Note: we assume a tie to the authentication option here. This
* is necessary so that authentication fails, we don't spin
* forever.
*/
if (telnetport && wantencryption) {
time_t timeout = time(0) + 60;
send_do(TELOPT_ENCRYPT, 1);
send_will(TELOPT_ENCRYPT, 1);
while (1) {
if (my_want_state_is_wont(TELOPT_AUTHENTICATION)) {
if (wantencryption == -1) {
break;
} else {
printf("\nServer refused to negotiate authentication,\n");
printf("which is required for encryption.\n");
Exit(1);
}
}
if (auth_has_failed) {
printf("\nAuthentication negotiation has failed,\n");
printf("which is required for encryption.\n");
Exit(1);
}
if (my_want_state_is_dont(TELOPT_ENCRYPT) ||
my_want_state_is_wont(TELOPT_ENCRYPT)) {
printf("\nServer refused to negotiate encryption.\n");
Exit(1);
}
if (encrypt_is_encrypting())
break;
if (time(0) > timeout) {
printf("\nEncryption could not be enabled.\n");
Exit(1);
}
if (printed_encrypt == 0) {
printed_encrypt = 1;
printf("Waiting for encryption to be negotiated...\n");
/*
* Turn on MODE_TRAPSIG and then turn off localchars
* so that ^C will cause telnet to exit.
*/
TerminalNewMode(getconnmode()|MODE_TRAPSIG);
intr_waiting = 1;
}
if (intr_happened) {
printf("\nUser interrupt.\n");
Exit(1);
}
if (telnet_spin()) {
printf("\nServer disconnected.\n");
Exit(1);
}
}
if (printed_encrypt) {
printf("Encryption negotiated.\n");
intr_waiting = 0;
setconnmode(0);
}
}
#endif
for (;;) {
int schedValue;
while ((schedValue = Scheduler(0)) != 0) {
if (schedValue == -1) {
setcommandmode();
return;
}
}
if (Scheduler(1) == -1) {
setcommandmode();
return;
}
}
}
/*
* localstat
*
* This function handles all management of linemode.
*
* Linemode allows the client to do the local editing of data
* and send only complete lines to the server. Linemode state is
* based on the state of the pty driver. If the pty is set for
* external processing, then we can use linemode. Further, if we
* can use real linemode, then we can look at the edit control bits
* in the pty to determine what editing the client should do.
*
* Linemode support uses the following state flags to keep track of
* current and desired linemode state.
* alwayslinemode : true if -l was specified on the telnetd
* command line. It means to have linemode on as much as
* possible.
*
* lmodetype: signifies whether the client can
* handle real linemode, or if use of kludgeomatic linemode
* is preferred. It will be set to one of the following:
* REAL_LINEMODE : use linemode option
* NO_KLUDGE : don't initiate kludge linemode.
* KLUDGE_LINEMODE : use kludge linemode
* NO_LINEMODE : client is ignorant of linemode
*
* linemode, uselinemode : linemode is true if linemode
* is currently on, uselinemode is the state that we wish
* to be in. If another function wishes to turn linemode
* on or off, it sets or clears uselinemode.
*
* editmode, useeditmode : like linemode/uselinemode, but
* these contain the edit mode states (edit and trapsig).
*
* The state variables correspond to some of the state information
* in the pty.
* linemode:
* In real linemode, this corresponds to whether the pty
* expects external processing of incoming data.
* In kludge linemode, this more closely corresponds to the
* whether normal processing is on or not. (ICANON in
* system V, or COOKED mode in BSD.)
* If the -l option was specified (alwayslinemode), then
* an attempt is made to force external processing on at
* all times.
*
* The following heuristics are applied to determine linemode
* handling within the server.
* 1) Early on in starting up the server, an attempt is made
* to negotiate the linemode option. If this succeeds
* then lmodetype is set to REAL_LINEMODE and all linemode
* processing occurs in the context of the linemode option.
* 2) If the attempt to negotiate the linemode option failed,
* and the "-k" (don't initiate kludge linemode) isn't set,
* then we try to use kludge linemode. We test for this
* capability by sending "do Timing Mark". If a positive
* response comes back, then we assume that the client
* understands kludge linemode (ech!) and the
* lmodetype flag is set to KLUDGE_LINEMODE.
* 3) Otherwise, linemode is not supported at all and
* lmodetype remains set to NO_LINEMODE (which happens
* to be 0 for convenience).
* 4) At any time a command arrives that implies a higher
* state of linemode support in the client, we move to that
* linemode support.
*
* A short explanation of kludge linemode is in order here.
* 1) The heuristic to determine support for kludge linemode
* is to send a do timing mark. We assume that a client
* that supports timing marks also supports kludge linemode.
* A risky proposition at best.
* 2) Further negotiation of linemode is done by changing the
* the server's state regarding SGA. If server will SGA,
* then linemode is off, if server won't SGA, then linemode
* is on.
*/
void
localstat(void)
{
int need_will_echo = 0;
/*
* Check for changes to flow control if client supports it.
*/
flowstat();
/*
* Check linemode on/off state
*/
uselinemode = tty_linemode();
/*
* If alwayslinemode is on, and pty is changing to turn it off, then
* force linemode back on.
*/
if (alwayslinemode && linemode && !uselinemode) {
uselinemode = 1;
tty_setlinemode(uselinemode);
}
if (uselinemode) {
/*
* Check for state of BINARY options.
*
* We only need to do the binary dance if we are actually going
* to use linemode. As this confuses some telnet clients
* that don't support linemode, and doesn't gain us
* anything, we don't do it unless we're doing linemode.
* -Crh ([email protected])
*/
if (tty_isbinaryin()) {
if (his_want_state_is_wont(TELOPT_BINARY))
send_do(TELOPT_BINARY, 1);
} else {
if (his_want_state_is_will(TELOPT_BINARY))
send_dont(TELOPT_BINARY, 1);
}
if (tty_isbinaryout()) {
if (my_want_state_is_wont(TELOPT_BINARY))
send_will(TELOPT_BINARY, 1);
} else {
if (my_want_state_is_will(TELOPT_BINARY))
send_wont(TELOPT_BINARY, 1);
}
}
#ifdef ENCRYPTION
/*
* If the terminal is not echoing, but editing is enabled,
* something like password input is going to happen, so
* if we the other side is not currently sending encrypted
* data, ask the other side to start encrypting.
*/
if (his_state_is_will(TELOPT_ENCRYPT)) {
static int enc_passwd = 0;
if (uselinemode && !tty_isecho() && tty_isediting()
&& (enc_passwd == 0) && !decrypt_input) {
encrypt_send_request_start();
enc_passwd = 1;
} else if (enc_passwd) {
encrypt_send_request_end();
enc_passwd = 0;
}
}
#endif /* ENCRYPTION */
/*
* Do echo mode handling as soon as we know what the
* linemode is going to be.
* If the pty has echo turned off, then tell the client that
* the server will echo. If echo is on, then the server
* will echo if in character mode, but in linemode the
* client should do local echoing. The state machine will
* not send anything if it is unnecessary, so don't worry
* about that here.
*
* If we need to send the WILL ECHO (because echo is off),
* then delay that until after we have changed the MODE.
* This way, when the user is turning off both editing
* and echo, the client will get editing turned off first.
* This keeps the client from going into encryption mode
* and then right back out if it is doing auto-encryption
* when passwords are being typed.
*/
if (uselinemode) {
if (tty_isecho())
send_wont(TELOPT_ECHO, 1);
else
need_will_echo = 1;
#ifdef KLUDGELINEMODE
if (lmodetype == KLUDGE_OK)
lmodetype = KLUDGE_LINEMODE;
#endif
}
/*
* If linemode is being turned off, send appropriate
* command and then we're all done.
*/
if (!uselinemode && linemode) {
# ifdef KLUDGELINEMODE
if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
send_dont(TELOPT_LINEMODE, 1);
# ifdef KLUDGELINEMODE
} else if (lmodetype == KLUDGE_LINEMODE)
send_will(TELOPT_SGA, 1);
# endif /* KLUDGELINEMODE */
send_will(TELOPT_ECHO, 1);
linemode = uselinemode;
goto done;
}
# ifdef KLUDGELINEMODE
/*
* If using real linemode check edit modes for possible later use.
* If we are in kludge linemode, do the SGA negotiation.
*/
if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
useeditmode = 0;
if (tty_isediting())
useeditmode |= MODE_EDIT;
if (tty_istrapsig())
useeditmode |= MODE_TRAPSIG;
if (tty_issofttab())
useeditmode |= MODE_SOFT_TAB;
if (tty_islitecho())
useeditmode |= MODE_LIT_ECHO;
# ifdef KLUDGELINEMODE
} else if (lmodetype == KLUDGE_LINEMODE) {
if (tty_isediting() && uselinemode)
send_wont(TELOPT_SGA, 1);
else
send_will(TELOPT_SGA, 1);
}
# endif /* KLUDGELINEMODE */
/*
* Negotiate linemode on if pty state has changed to turn it on.
* Send appropriate command and send along edit mode, then all done.
*/
if (uselinemode && !linemode) {
# ifdef KLUDGELINEMODE
if (lmodetype == KLUDGE_LINEMODE) {
send_wont(TELOPT_SGA, 1);
} else if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
send_do(TELOPT_LINEMODE, 1);
/* send along edit modes */
output_data("%c%c%c%c%c%c%c", IAC, SB,
TELOPT_LINEMODE, LM_MODE, useeditmode,
IAC, SE);
editmode = useeditmode;
# ifdef KLUDGELINEMODE
}
# endif /* KLUDGELINEMODE */
linemode = uselinemode;
goto done;
}
# ifdef KLUDGELINEMODE
/*
* None of what follows is of any value if not using
* real linemode.
*/
if (lmodetype < REAL_LINEMODE)
goto done;
# endif /* KLUDGELINEMODE */
if (linemode && his_state_is_will(TELOPT_LINEMODE)) {
/*
* If edit mode changed, send edit mode.
*/
if (useeditmode != editmode) {
/*
* Send along appropriate edit mode mask.
*/
output_data("%c%c%c%c%c%c%c", IAC, SB,
TELOPT_LINEMODE, LM_MODE, useeditmode,
IAC, SE);
editmode = useeditmode;
}
/*
* Check for changes to special characters in use.
*/
start_slc(0);
check_slc();
(void) end_slc(0);
}
done:
if (need_will_echo)
send_will(TELOPT_ECHO, 1);
/*
* Some things should be deferred until after the pty state has
* been set by the local process. Do those things that have been
* deferred now. This only happens once.
*/
if (_terminit == 0) {
_terminit = 1;
defer_terminit();
}
netflush();
set_termbuf();
return;
} /* end of localstat */
static
int
getterminaltype(char *name)
{
int retval = -1;
(void)name;
settimer(baseline);
#if defined(AUTHENTICATE)
/*
* Handle the Authentication option before we do anything else.
*/
send_do(TELOPT_AUTHENTICATION, 1);
while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
ttloop();
if (his_state_is_will(TELOPT_AUTHENTICATION)) {
retval = auth_wait(name);
}
#endif
#if defined(ENCRYPT)
send_will(TELOPT_ENCRYPT, 1);
#endif
send_do(TELOPT_TTYPE, 1);
send_do(TELOPT_TSPEED, 1);
send_do(TELOPT_XDISPLOC, 1);
send_do(TELOPT_ENVIRON, 1);
while (
#if defined(ENCRYPT)
his_do_dont_is_changing(TELOPT_ENCRYPT) ||
#endif
his_will_wont_is_changing(TELOPT_TTYPE) ||
his_will_wont_is_changing(TELOPT_TSPEED) ||
his_will_wont_is_changing(TELOPT_XDISPLOC) ||
his_will_wont_is_changing(TELOPT_ENVIRON)) {
ttloop();
}
#if defined(ENCRYPT)
/*
* Wait for the negotiation of what type of encryption we can
* send with. If autoencrypt is not set, this will just return.
*/
if (his_state_is_will(TELOPT_ENCRYPT)) {
encrypt_wait();
}
#endif
if (his_state_is_will(TELOPT_TSPEED)) {
static char sbbuf[] = { IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE };
bcopy(sbbuf, nfrontp, sizeof sbbuf);
nfrontp += sizeof sbbuf;
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
static char sbbuf[] = { IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE };
bcopy(sbbuf, nfrontp, sizeof sbbuf);
nfrontp += sizeof sbbuf;
}
if (his_state_is_will(TELOPT_ENVIRON)) {
static char sbbuf[] = { IAC, SB, TELOPT_ENVIRON, TELQUAL_SEND, IAC, SE };
bcopy(sbbuf, nfrontp, sizeof sbbuf);
nfrontp += sizeof sbbuf;
}
if (his_state_is_will(TELOPT_TTYPE)) {
bcopy(ttytype_sbbuf, nfrontp, sizeof ttytype_sbbuf);
nfrontp += sizeof ttytype_sbbuf;
}
if (his_state_is_will(TELOPT_TSPEED)) {
while (sequenceIs(tspeedsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
while (sequenceIs(xdisplocsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_ENVIRON)) {
while (sequenceIs(environsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_TTYPE)) {
char first[256], last[256];
while (sequenceIs(ttypesubopt, baseline))
ttloop();
/*
* If the other side has already disabled the option, then
* we have to just go with what we (might) have already gotten.
*/
if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
(void) strncpy(first, terminaltype, sizeof(first));
for(;;) {
/*
* Save the unknown name, and request the next name.
*/
(void) strncpy(last, terminaltype, sizeof(last));
_gettermname();
if (terminaltypeok(terminaltype))
break;
if ((strncmp(last, terminaltype, sizeof(last)) == 0) ||
his_state_is_wont(TELOPT_TTYPE)) {
/*
* We've hit the end. If this is the same as
* the first name, just go with it.
*/
if (strncmp(first, terminaltype, sizeof(first)) == 0)
break;
/*
* Get the terminal name one more time, so that
* RFC1091 compliant telnets will cycle back to
* the start of the list.
*/
_gettermname();
if (strncmp(first, terminaltype, sizeof(first)) != 0)
(void) strncpy(terminaltype, first, sizeof(first));
break;
}
}
}
}
return(retval);
} /* end of getterminaltype */
void willoption(int option) {
int changeok = 0;
void (*func)(void) = 0;
/*
* process input from peer.
*/
DIAG(TD_OPTIONS, printoption("td: recv will", option));
if (do_dont_resp[option]) {
do_dont_resp[option]--;
if (do_dont_resp[option] && his_state_is_will(option))
do_dont_resp[option]--;
}
if (do_dont_resp[option] == 0) {
if (his_want_state_is_wont(option)) {
switch (option) {
case TELOPT_BINARY:
init_termbuf();
tty_binaryin(1);
set_termbuf();
changeok++;
break;
case TELOPT_ECHO:
/*
* See comments below for more info.
*/
not42 = 0; /* looks like a 4.2 system */
break;
case TELOPT_TM:
#if defined(LINEMODE) && defined(KLUDGELINEMODE)
/*
* This telnetd implementation does not really
* support timing marks, it just uses them to
* support the kludge linemode stuff. If we
* receive a will or wont TM in response to our
* do TM request that may have been sent to
* determine kludge linemode support, process
* it, otherwise TM should get a negative
* response back.
*/
/*
* Handle the linemode kludge stuff.
* If we are not currently supporting any
* linemode at all, then we assume that this
* is the client telling us to use kludge
* linemode in response to our query. Set the
* linemode type that is to be supported, note
* that the client wishes to use linemode, and
* eat the will TM as though it never arrived.
*/
if (lmodetype < KLUDGE_LINEMODE) {
lmodetype = KLUDGE_LINEMODE;
clientstat(TELOPT_LINEMODE, WILL, 0);
send_wont(TELOPT_SGA, 1);
}
#endif /* defined(LINEMODE) && defined(KLUDGELINEMODE) */
/*
* We never respond to a WILL TM, and
* we leave the state WONT.
*/
return;
case TELOPT_LFLOW:
/*
* If we are going to support flow control
* option, then don't worry peer that we can't
* change the flow control characters.
*/
slctab[SLC_XON].defset.flag &= ~SLC_LEVELBITS;
slctab[SLC_XON].defset.flag |= SLC_DEFAULT;
slctab[SLC_XOFF].defset.flag &= ~SLC_LEVELBITS;
slctab[SLC_XOFF].defset.flag |= SLC_DEFAULT;
case TELOPT_TTYPE:
case TELOPT_SGA:
case TELOPT_NAWS:
case TELOPT_TSPEED:
case TELOPT_XDISPLOC:
case TELOPT_ENVIRON:
changeok++;
break;
#ifdef LINEMODE
case TELOPT_LINEMODE:
#ifdef KLUDGELINEMODE
/*
* Note client's desire to use linemode.
*/
lmodetype = REAL_LINEMODE;
#endif /* KLUDGELINEMODE */
func = doclientstat;
changeok++;
break;
#endif /* LINEMODE */
#ifdef AUTHENTICATE
case TELOPT_AUTHENTICATION:
func = auth_request;
changeok++;
break;
#endif
#ifdef ENCRYPT
case TELOPT_ENCRYPT:
func = encrypt_send_support;
changeok++;
break;
#endif
default:
break;
}
if (changeok) {
set_his_want_state_will(option);
send_do(option, 0);
}
else {
do_dont_resp[option]++;
send_dont(option, 0);
}
}
else {
/*
* Option processing that should happen when
* we receive conformation of a change in
* state that we had requested.
*/
switch (option) {
case TELOPT_ECHO:
not42 = 0; /* looks like a 4.2 system */
/*
* Egads, he responded "WILL ECHO". Turn
* it off right now!
*/
send_dont(option, 1);
/*
* "WILL ECHO". Kludge upon kludge!
* A 4.2 client is now echoing user input at
* the tty. This is probably undesireable and
* it should be stopped. The client will
* respond WONT TM to the DO TM that we send to
* check for kludge linemode. When the WONT TM
* arrives, linemode will be turned off and a
* change propogated to the pty. This change
* will cause us to process the new pty state
* in localstat(), which will notice that
* linemode is off and send a WILL ECHO
* so that we are properly in character mode and
* all is well.
*/
break;
#ifdef LINEMODE
case TELOPT_LINEMODE:
# ifdef KLUDGELINEMODE
/*
* Note client's desire to use linemode.
*/
lmodetype = REAL_LINEMODE;
# endif /* KLUDGELINEMODE */
func = doclientstat;
break;
#endif /* LINEMODE */
#ifdef AUTHENTICATE
case TELOPT_AUTHENTICATION:
func = auth_request;
break;
#endif
#ifdef ENCRYPT
case TELOPT_ENCRYPT:
func = encrypt_send_support;
break;
#endif
}
}
}
set_his_state_will(option);
if (func) (*func)();
}
/*
* localstat
*
* This function handles all management of linemode.
*
* Linemode allows the client to do the local editing of data
* and send only complete lines to the server. Linemode state is
* based on the state of the pty driver. If the pty is set for
* external processing, then we can use linemode. Further, if we
* can use real linemode, then we can look at the edit control bits
* in the pty to determine what editing the client should do.
*
* Linemode support uses the following state flags to keep track of
* current and desired linemode state.
* alwayslinemode : true if -l was specified on the telnetd
* command line. It means to have linemode on as much as
* possible.
*
* lmodetype: signifies whether the client can
* handle real linemode, or if use of kludgeomatic linemode
* is preferred. It will be set to one of the following:
* REAL_LINEMODE : use linemode option
* NO_KLUDGE : don't initiate kludge linemode.
* KLUDGE_LINEMODE : use kludge linemode
* NO_LINEMODE : client is ignorant of linemode
*
* linemode, uselinemode : linemode is true if linemode
* is currently on, uselinemode is the state that we wish
* to be in. If another function wishes to turn linemode
* on or off, it sets or clears uselinemode.
*
* editmode, useeditmode : like linemode/uselinemode, but
* these contain the edit mode states (edit and trapsig).
*
* The state variables correspond to some of the state information
* in the pty.
* linemode:
* In real linemode, this corresponds to whether the pty
* expects external processing of incoming data.
* In kludge linemode, this more closely corresponds to the
* whether normal processing is on or not. (ICANON in
* system V, or COOKED mode in BSD.)
* If the -l option was specified (alwayslinemode), then
* an attempt is made to force external processing on at
* all times.
*
* The following heuristics are applied to determine linemode
* handling within the server.
* 1) Early on in starting up the server, an attempt is made
* to negotiate the linemode option. If this succeeds
* then lmodetype is set to REAL_LINEMODE and all linemode
* processing occurs in the context of the linemode option.
* 2) If the attempt to negotiate the linemode option failed,
* and the "-k" (don't initiate kludge linemode) isn't set,
* then we try to use kludge linemode. We test for this
* capability by sending "do Timing Mark". If a positive
* response comes back, then we assume that the client
* understands kludge linemode (ech!) and the
* lmodetype flag is set to KLUDGE_LINEMODE.
* 3) Otherwise, linemode is not supported at all and
* lmodetype remains set to NO_LINEMODE (which happens
* to be 0 for convenience).
* 4) At any time a command arrives that implies a higher
* state of linemode support in the client, we move to that
* linemode support.
*
* A short explanation of kludge linemode is in order here.
* 1) The heuristic to determine support for kludge linemode
* is to send a do timing mark. We assume that a client
* that supports timing marks also supports kludge linemode.
* A risky proposition at best.
* 2) Further negotiation of linemode is done by changing the
* the server's state regarding SGA. If server will SGA,
* then linemode is off, if server won't SGA, then linemode
* is on.
*/
void
localstat()
{
int need_will_echo = 0;
#if defined(CRAY2) && defined(UNICOS5)
/*
* Keep track of that ol' CR/NL mapping while we're in the
* neighborhood.
*/
newmap = tty_isnewmap();
#endif /* defined(CRAY2) && defined(UNICOS5) */
/*
* Check for state of BINARY options.
*/
if (tty_isbinaryin()) {
if (his_want_state_is_wont(TELOPT_BINARY))
send_do(TELOPT_BINARY, 1);
} else {
if (his_want_state_is_will(TELOPT_BINARY))
send_dont(TELOPT_BINARY, 1);
}
if (tty_isbinaryout()) {
if (my_want_state_is_wont(TELOPT_BINARY))
send_will(TELOPT_BINARY, 1);
} else {
if (my_want_state_is_will(TELOPT_BINARY))
send_wont(TELOPT_BINARY, 1);
}
/*
* Check for changes to flow control if client supports it.
*/
flowstat();
/*
* Check linemode on/off state
*/
uselinemode = tty_linemode();
/*
* If alwayslinemode is on, and pty is changing to turn it off, then
* force linemode back on.
*/
if (alwayslinemode && linemode && !uselinemode) {
uselinemode = 1;
tty_setlinemode(uselinemode);
}
/*
* Do echo mode handling as soon as we know what the
* linemode is going to be.
* If the pty has echo turned off, then tell the client that
* the server will echo. If echo is on, then the server
* will echo if in character mode, but in linemode the
* client should do local echoing. The state machine will
* not send anything if it is unnecessary, so don't worry
* about that here.
*
* If we need to send the WILL ECHO (because echo is off),
* then delay that until after we have changed the MODE.
* This way, when the user is turning off both editing
* and echo, the client will get editing turned off first.
* This keeps the client from going into encryption mode
* and then right back out if it is doing auto-encryption
* when passwords are being typed.
*/
if (uselinemode) {
if (tty_isecho())
send_wont(TELOPT_ECHO, 1);
else
need_will_echo = 1;
#ifdef KLUDGELINEMODE
if (lmodetype == KLUDGE_OK)
lmodetype = KLUDGE_LINEMODE;
#endif
}
/*
* If linemode is being turned off, send appropriate
* command and then we're all done.
*/
if (!uselinemode && linemode) {
# ifdef KLUDGELINEMODE
if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
send_dont(TELOPT_LINEMODE, 1);
# ifdef KLUDGELINEMODE
} else if (lmodetype == KLUDGE_LINEMODE)
send_will(TELOPT_SGA, 1);
# endif /* KLUDGELINEMODE */
send_will(TELOPT_ECHO, 1);
linemode = uselinemode;
goto done;
}
# ifdef KLUDGELINEMODE
/*
* If using real linemode check edit modes for possible later use.
* If we are in kludge linemode, do the SGA negotiation.
*/
if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
useeditmode = 0;
if (tty_isediting())
useeditmode |= MODE_EDIT;
if (tty_istrapsig())
useeditmode |= MODE_TRAPSIG;
if (tty_issofttab())
useeditmode |= MODE_SOFT_TAB;
if (tty_islitecho())
useeditmode |= MODE_LIT_ECHO;
# ifdef KLUDGELINEMODE
} else if (lmodetype == KLUDGE_LINEMODE) {
if (tty_isediting() && uselinemode)
send_wont(TELOPT_SGA, 1);
else
send_will(TELOPT_SGA, 1);
}
# endif /* KLUDGELINEMODE */
/*
* Negotiate linemode on if pty state has changed to turn it on.
* Send appropriate command and send along edit mode, then all done.
*/
if (uselinemode && !linemode) {
# ifdef KLUDGELINEMODE
if (lmodetype == KLUDGE_LINEMODE) {
send_wont(TELOPT_SGA, 1);
} else if (lmodetype == REAL_LINEMODE) {
# endif /* KLUDGELINEMODE */
send_do(TELOPT_LINEMODE, 1);
/* send along edit modes */
(void) sprintf(nfrontp, "%c%c%c%c%c%c%c", IAC, SB,
TELOPT_LINEMODE, LM_MODE, useeditmode,
IAC, SE);
nfrontp += 7;
editmode = useeditmode;
# ifdef KLUDGELINEMODE
}
# endif /* KLUDGELINEMODE */
linemode = uselinemode;
goto done;
}
# ifdef KLUDGELINEMODE
/*
* None of what follows is of any value if not using
* real linemode.
*/
if (lmodetype < REAL_LINEMODE)
goto done;
# endif /* KLUDGELINEMODE */
if (linemode && his_state_is_will(TELOPT_LINEMODE)) {
/*
* If edit mode changed, send edit mode.
*/
if (useeditmode != editmode) {
/*
* Send along appropriate edit mode mask.
*/
(void) sprintf(nfrontp, "%c%c%c%c%c%c%c", IAC, SB,
TELOPT_LINEMODE, LM_MODE, useeditmode,
IAC, SE);
nfrontp += 7;
editmode = useeditmode;
}
/*
* Check for changes to special characters in use.
*/
start_slc(0);
check_slc();
(void) end_slc(0);
}
done:
if (need_will_echo)
send_will(TELOPT_ECHO, 1);
/*
* Some things should be deferred until after the pty state has
* been set by the local process. Do those things that have been
* deferred now. This only happens once.
*/
if (_terminit == 0) {
_terminit = 1;
defer_terminit();
}
netflush();
set_termbuf();
return;
} /* end of localstat */
/*
* Main loop. Select from pty and network, and
* hand data to telnet receiver finite state machine.
*/
void telnet(int f, int p)
{
int on = 1;
char *HE;
const char *IM;
/*
* Initialize the slc mapping table.
*/
get_slc_defaults();
/*
* Do some tests where it is desireable to wait for a response.
* Rather than doing them slowly, one at a time, do them all
* at once.
*/
if (my_state_is_wont(TELOPT_SGA))
send_will(TELOPT_SGA, 1);
/*
* Is the client side a 4.2 (NOT 4.3) system? We need to know this
* because 4.2 clients are unable to deal with TCP urgent data.
*
* To find out, we send out a "DO ECHO". If the remote system
* answers "WILL ECHO" it is probably a 4.2 client, and we note
* that fact ("WILL ECHO" ==> that the client will echo what
* WE, the server, sends it; it does NOT mean that the client will
* echo the terminal input).
*/
send_do(TELOPT_ECHO, 1);
#ifdef LINEMODE
if (his_state_is_wont(TELOPT_LINEMODE)) {
/*
* Query the peer for linemode support by trying to negotiate
* the linemode option.
*/
linemode = 0;
editmode = 0;
send_do(TELOPT_LINEMODE, 1); /* send do linemode */
}
#endif /* LINEMODE */
/*
* Send along a couple of other options that we wish to negotiate.
*/
send_do(TELOPT_NAWS, 1);
send_will(TELOPT_STATUS, 1);
flowmode = 1; /* default flow control state */
send_do(TELOPT_LFLOW, 1);
/*
* Spin, waiting for a response from the DO ECHO. However,
* some REALLY DUMB telnets out there might not respond
* to the DO ECHO. So, we spin looking for NAWS, (most dumb
* telnets so far seem to respond with WONT for a DO that
* they don't understand...) because by the time we get the
* response, it will already have processed the DO ECHO.
* Kludge upon kludge.
*/
while (his_will_wont_is_changing(TELOPT_NAWS)) {
ttloop();
}
/*
* But...
* The client might have sent a WILL NAWS as part of its
* startup code; if so, we'll be here before we get the
* response to the DO ECHO. We'll make the assumption
* that any implementation that understands about NAWS
* is a modern enough implementation that it will respond
* to our DO ECHO request; hence we'll do another spin
* waiting for the ECHO option to settle down, which is
* what we wanted to do in the first place...
*/
if (his_want_state_is_will(TELOPT_ECHO) &&
his_state_is_will(TELOPT_NAWS)) {
while (his_will_wont_is_changing(TELOPT_ECHO))
ttloop();
}
/*
* On the off chance that the telnet client is broken and does not
* respond to the DO ECHO we sent, (after all, we did send the
* DO NAWS negotiation after the DO ECHO, and we won't get here
* until a response to the DO NAWS comes back) simulate the
* receipt of a will echo. This will also send a WONT ECHO
* to the client, since we assume that the client failed to
* respond because it believes that it is already in DO ECHO
* mode, which we do not want.
*/
if (his_want_state_is_will(TELOPT_ECHO)) {
DIAG(TD_OPTIONS, netoprintf("td: simulating recv\r\n"););
willoption(TELOPT_ECHO);
}
static
int
getterminaltype(char *name)
{
int retval = -1;
(void)name;
settimer(baseline);
#if defined(AUTHENTICATE)
/*
* Handle the Authentication option before we do anything else.
*/
send_do(TELOPT_AUTHENTICATION, 1);
while (his_will_wont_is_changing(TELOPT_AUTHENTICATION))
ttloop();
if (his_state_is_will(TELOPT_AUTHENTICATION)) {
retval = auth_wait(name);
}
#endif
#if defined(ENCRYPT)
send_will(TELOPT_ENCRYPT, 1);
#endif
send_do(TELOPT_TTYPE, 1);
send_do(TELOPT_TSPEED, 1);
send_do(TELOPT_XDISPLOC, 1);
send_do(TELOPT_ENVIRON, 1);
while (
#if defined(ENCRYPT)
his_do_dont_is_changing(TELOPT_ENCRYPT) ||
#endif
his_will_wont_is_changing(TELOPT_TTYPE) ||
his_will_wont_is_changing(TELOPT_TSPEED) ||
his_will_wont_is_changing(TELOPT_XDISPLOC) ||
his_will_wont_is_changing(TELOPT_ENVIRON)) {
ttloop();
}
#if defined(ENCRYPT)
/*
* Wait for the negotiation of what type of encryption we can
* send with. If autoencrypt is not set, this will just return.
*/
if (his_state_is_will(TELOPT_ENCRYPT)) {
encrypt_wait();
}
#endif
if (his_state_is_will(TELOPT_TSPEED)) {
netoprintf("%c%c%c%c%c%c",
IAC, SB, TELOPT_TSPEED, TELQUAL_SEND, IAC, SE);
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
netoprintf("%c%c%c%c%c%c",
IAC, SB, TELOPT_XDISPLOC, TELQUAL_SEND, IAC, SE);
}
if (his_state_is_will(TELOPT_ENVIRON)) {
netoprintf("%c%c%c%c%c%c",
IAC, SB, TELOPT_ENVIRON, TELQUAL_SEND, IAC, SE);
}
if (his_state_is_will(TELOPT_TTYPE)) {
netoprintf("%c%c%c%c%c%c",
IAC, SB, TELOPT_TTYPE, TELQUAL_SEND, IAC, SE);
}
if (his_state_is_will(TELOPT_TSPEED)) {
while (sequenceIs(tspeedsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_XDISPLOC)) {
while (sequenceIs(xdisplocsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_ENVIRON)) {
while (sequenceIs(environsubopt, baseline))
ttloop();
}
if (his_state_is_will(TELOPT_TTYPE)) {
char first[256], last[256];
while (sequenceIs(ttypesubopt, baseline))
ttloop();
/*
* If the other side has already disabled the option, then
* we have to just go with what we (might) have already gotten.
*/
if (his_state_is_will(TELOPT_TTYPE) && !terminaltypeok(terminaltype)) {
/*
* Due to state.c, terminaltype points to a static char[41].
* Therefore, this assert cannot fail, and therefore, strings
* arising from "terminaltype" can be safely strcpy'd into
* first[] or last[].
*/
assert(strlen(terminaltype) < sizeof(first));
strcpy(first, terminaltype);
for(;;) {
/*
* Save the unknown name, and request the next name.
*/
strcpy(last, terminaltype);
_gettermname();
assert(strlen(terminaltype) < sizeof(first));
if (terminaltypeok(terminaltype))
break;
if (!strcmp(last, terminaltype) ||
his_state_is_wont(TELOPT_TTYPE)) {
/*
* We've hit the end. If this is the same as
* the first name, just go with it.
*/
if (!strcmp(first, terminaltype))
break;
/*
* Get the terminal name one more time, so that
* RFC1091 compliant telnets will cycle back to
* the start of the list.
*/
_gettermname();
assert(strlen(terminaltype) < sizeof(first));
if (strcmp(first, terminaltype)) {
/*
* first[] came from terminaltype, so it must fit
* back in.
*/
strcpy(terminaltype, first);
}
break;
}
}
}
}
return(retval);
} /* end of getterminaltype */
