void
telrcv()
{
register int c;
static int state = TS_DATA;
#if defined(CRAY2) && defined(UNICOS5)
char *opfrontp = pfrontp;
#endif
while (ncc > 0) {
if ((&ptyobuf[BUFSIZ] - pfrontp) < 2)
break;
c = *netip++ & 0377, ncc--;
switch (state) {
case TS_CR:
state = TS_DATA;
/* Strip off \n or \0 after a \r */
if ((c == 0) || (c == '\n')) {
break;
}
/* FALL THROUGH */
case TS_DATA:
if (c == IAC) {
state = TS_IAC;
break;
}
/*
* We now map \r\n ==> \r for pragmatic reasons.
* Many client implementations send \r\n when
* the user hits the CarriageReturn key.
*
* We USED to map \r\n ==> \n, since \r\n says
* that we want to be in column 1 of the next
* printable line, and \n is the standard
* unix way of saying that (\r is only good
* if CRMOD is set, which it normally is).
*/
if ((c == '\r') && his_state_is_wont(TELOPT_BINARY)) {
int nc = *netip;
#ifdef LINEMODE
/*
* If we are operating in linemode,
* convert to local end-of-line.
*/
if (linemode && (ncc > 0) && (('\n' == nc) ||
((0 == nc) && tty_iscrnl())) ) {
netip++;
ncc--;
c = '\n';
} else
#endif
{
state = TS_CR;
}
}
*pfrontp++ = c;
break;
case TS_IAC:
gotiac:
switch (c) {
/*
* Send the process on the pty side an
* interrupt. Do this with a NULL or
* interrupt char; depending on the tty mode.
*/
case IP:
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
interrupt();
break;
case BREAK:
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
sendbrk();
break;
/*
* Are You There?
*/
case AYT:
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
recv_ayt();
break;
/*
* Abort Output
*/
case AO:
{
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
ptyflush(); /* half-hearted */
init_termbuf();
if (slctab[SLC_AO].sptr &&
*slctab[SLC_AO].sptr != (cc_t)(_POSIX_VDISABLE)) {
*pfrontp++ =
(unsigned char)*slctab[SLC_AO].sptr;
}
netclear(); /* clear buffer back */
*nfrontp++ = IAC;
*nfrontp++ = DM;
neturg = nfrontp-1; /* off by one XXX */
DIAG(TD_OPTIONS,
printoption("td: send IAC", DM));
break;
}
/*
* Erase Character and
* Erase Line
*/
case EC:
case EL:
{
cc_t ch;
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
ptyflush(); /* half-hearted */
init_termbuf();
if (c == EC)
ch = *slctab[SLC_EC].sptr;
else
ch = *slctab[SLC_EL].sptr;
if (ch != (cc_t)(_POSIX_VDISABLE))
*pfrontp++ = (unsigned char)ch;
break;
}
/*
* Check for urgent data...
*/
case DM:
DIAG(TD_OPTIONS,
printoption("td: recv IAC", c));
SYNCHing = stilloob(net);
settimer(gotDM);
break;
/*
* Begin option subnegotiation...
*/
case SB:
state = TS_SB;
SB_CLEAR();
continue;
case WILL:
state = TS_WILL;
continue;
case WONT:
state = TS_WONT;
continue;
case DO:
state = TS_DO;
continue;
case DONT:
state = TS_DONT;
continue;
case EOR:
if (his_state_is_will(TELOPT_EOR))
doeof();
break;
/*
* Handle RFC 10xx Telnet linemode option additions
* to command stream (EOF, SUSP, ABORT).
*/
case xEOF:
doeof();
break;
case SUSP:
sendsusp();
break;
case ABORT:
sendbrk();
break;
case IAC:
*pfrontp++ = c;
break;
}
state = TS_DATA;
break;
case TS_SB:
if (c == IAC) {
state = TS_SE;
} else {
SB_ACCUM(c);
}
break;
case TS_SE:
if (c != SE) {
if (c != IAC) {
/*
* bad form of suboption negotiation.
* handle it in such a way as to avoid
* damage to local state. Parse
* suboption buffer found so far,
* then treat remaining stream as
* another command sequence.
*/
/* for DIAGNOSTICS */
SB_ACCUM(IAC);
SB_ACCUM(c);
subpointer -= 2;
SB_TERM();
suboption();
state = TS_IAC;
goto gotiac;
}
SB_ACCUM(c);
state = TS_SB;
} else {
/* for DIAGNOSTICS */
SB_ACCUM(IAC);
SB_ACCUM(SE);
subpointer -= 2;
SB_TERM();
suboption(); /* handle sub-option */
state = TS_DATA;
}
break;
case TS_WILL:
willoption(c);
state = TS_DATA;
continue;
case TS_WONT:
wontoption(c);
state = TS_DATA;
continue;
case TS_DO:
dooption(c);
state = TS_DATA;
continue;
case TS_DONT:
dontoption(c);
state = TS_DATA;
continue;
default:
syslog(LOG_ERR, "telnetd: panic state=%d\n", state);
printf("telnetd: panic state=%d\n", state);
exit(1);
}
}
#if defined(CRAY2) && defined(UNICOS5)
if (!linemode) {
char xptyobuf[BUFSIZ+NETSLOP];
char xbuf2[BUFSIZ];
register char *cp;
int n = pfrontp - opfrontp, oc;
memmove(xptyobuf, opfrontp, n);
pfrontp = opfrontp;
pfrontp += term_input(xptyobuf, pfrontp, n, BUFSIZ+NETSLOP,
xbuf2, &oc, BUFSIZ);
for (cp = xbuf2; oc > 0; --oc)
if ((*nfrontp++ = *cp++) == IAC)
*nfrontp++ = IAC;
}
#endif /* defined(CRAY2) && defined(UNICOS5) */
} /* end of telrcv */
int
telrcv(void)
{
int c;
int scc;
unsigned char *sbp;
int count;
int returnValue = 0;
scc = 0;
count = 0;
while (TTYROOM() > 2) {
if (scc == 0) {
if (count) {
ring_consumed(&netiring, count);
returnValue = 1;
count = 0;
}
sbp = netiring.consume;
scc = ring_full_consecutive(&netiring);
if (scc == 0) {
/* No more data coming in */
break;
}
}
c = *sbp++ & 0xff, scc--; count++;
#ifdef ENCRYPTION
if (decrypt_input)
c = (*decrypt_input)(c);
#endif /* ENCRYPTION */
switch (telrcv_state) {
case TS_CR:
telrcv_state = TS_DATA;
if (c == '\0') {
break; /* Ignore \0 after CR */
}
else if ((c == '\n') && my_want_state_is_dont(TELOPT_ECHO) && !crmod) {
TTYADD(c);
break;
}
/* Else, fall through */
case TS_DATA:
if (c == IAC) {
telrcv_state = TS_IAC;
break;
}
/*
* The 'crmod' hack (see following) is needed
* since we can't * set CRMOD on output only.
* Machines like MULTICS like to send \r without
* \n; since we must turn off CRMOD to get proper
* input, the mapping is done here (sigh).
*/
if ((c == '\r') && my_want_state_is_dont(TELOPT_BINARY)) {
if (scc > 0) {
c = *sbp&0xff;
#ifdef ENCRYPTION
if (decrypt_input)
c = (*decrypt_input)(c);
#endif /* ENCRYPTION */
if (c == 0) {
sbp++, scc--; count++;
/* a "true" CR */
TTYADD('\r');
} else if (my_want_state_is_dont(TELOPT_ECHO) &&
(c == '\n')) {
sbp++, scc--; count++;
TTYADD('\n');
} else {
#ifdef ENCRYPTION
if (decrypt_input)
(*decrypt_input)(-1);
#endif /* ENCRYPTION */
TTYADD('\r');
if (crmod) {
TTYADD('\n');
}
}
} else {
telrcv_state = TS_CR;
TTYADD('\r');
if (crmod) {
TTYADD('\n');
}
}
} else {
TTYADD(c);
}
continue;
case TS_IAC:
process_iac:
switch (c) {
case WILL:
telrcv_state = TS_WILL;
continue;
case WONT:
telrcv_state = TS_WONT;
continue;
case DO:
telrcv_state = TS_DO;
continue;
case DONT:
telrcv_state = TS_DONT;
continue;
case DM:
/*
* We may have missed an urgent notification,
* so make sure we flush whatever is in the
* buffer currently.
*/
printoption("RCVD", IAC, DM);
SYNCHing = 1;
(void) ttyflush(1);
SYNCHing = stilloob();
settimer(gotDM);
break;
case SB:
SB_CLEAR();
telrcv_state = TS_SB;
continue;
case IAC:
TTYADD(IAC);
break;
case NOP:
case GA:
default:
printoption("RCVD", IAC, c);
break;
}
telrcv_state = TS_DATA;
continue;
case TS_WILL:
printoption("RCVD", WILL, c);
willoption(c);
telrcv_state = TS_DATA;
continue;
case TS_WONT:
printoption("RCVD", WONT, c);
wontoption(c);
telrcv_state = TS_DATA;
continue;
case TS_DO:
printoption("RCVD", DO, c);
dooption(c);
if (c == TELOPT_NAWS) {
sendnaws();
} else if (c == TELOPT_LFLOW) {
localflow = 1;
setcommandmode();
setconnmode(0);
}
telrcv_state = TS_DATA;
continue;
case TS_DONT:
printoption("RCVD", DONT, c);
dontoption(c);
flushline = 1;
setconnmode(0); /* set new tty mode (maybe) */
telrcv_state = TS_DATA;
continue;
case TS_SB:
if (c == IAC) {
telrcv_state = TS_SE;
} else {
SB_ACCUM(c);
}
continue;
case TS_SE:
if (c != SE) {
if (c != IAC) {
/*
* This is an error. We only expect to get
* "IAC IAC" or "IAC SE". Several things may
* have happend. An IAC was not doubled, the
* IAC SE was left off, or another option got
* inserted into the suboption are all possibilities.
* If we assume that the IAC was not doubled,
* and really the IAC SE was left off, we could
* get into an infinate loop here. So, instead,
* we terminate the suboption, and process the
* partial suboption if we can.
*/
SB_ACCUM(IAC);
SB_ACCUM(c);
subpointer -= 2;
SB_TERM();
printoption("In SUBOPTION processing, RCVD", IAC, c);
suboption(); /* handle sub-option */
telrcv_state = TS_IAC;
goto process_iac;
}
SB_ACCUM(c);
telrcv_state = TS_SB;
} else {
SB_ACCUM(IAC);
SB_ACCUM(SE);
subpointer -= 2;
SB_TERM();
suboption(); /* handle sub-option */
telrcv_state = TS_DATA;
}
}
}
if (count)
ring_consumed(&netiring, count);
return returnValue||count;
}
int
process_rings (int netin, int netout, int netex, int ttyin, int ttyout,
int poll)
/* If poll == 0, then block until something to do */
{
int c;
/* One wants to be a bit careful about setting returnValue
* to one, since a one implies we did some useful work,
* and therefore probably won't be called to block next
* time (TN3270 mode only).
*/
int returnValue = 0;
static struct timeval TimeValue = { 0, 0 };
int maxfd = -1;
int tmp;
if ((netout || netin || netex) && net > maxfd)
maxfd = net;
if (ttyout && tout > maxfd)
maxfd = tout;
if (ttyin && tin > maxfd)
maxfd = tin;
tmp = howmany (maxfd + 1, NFDBITS) * sizeof (fd_mask);
if (tmp > fdsn)
{
if (ibitsp)
free (ibitsp);
if (obitsp)
free (obitsp);
if (xbitsp)
free (xbitsp);
fdsn = tmp;
if ((ibitsp = (fd_set *) malloc (fdsn)) == NULL)
err (1, "malloc");
if ((obitsp = (fd_set *) malloc (fdsn)) == NULL)
err (1, "malloc");
if ((xbitsp = (fd_set *) malloc (fdsn)) == NULL)
err (1, "malloc");
memset (ibitsp, 0, fdsn);
memset (obitsp, 0, fdsn);
memset (xbitsp, 0, fdsn);
}
if (netout)
FD_SET (net, obitsp);
if (ttyout)
FD_SET (tout, obitsp);
if (ttyin)
FD_SET (tin, ibitsp);
if (netin)
FD_SET (net, ibitsp);
if (netex)
FD_SET (net, xbitsp);
if ((c = select (maxfd + 1, ibitsp, obitsp, xbitsp,
(poll == 0) ? (struct timeval *) 0 : &TimeValue)) < 0)
{
if (c == -1)
{
/*
* we can get EINTR if we are in line mode,
* and the user does an escape (TSTP), or
* some other signal generator.
*/
if (errno == EINTR)
{
return 0;
}
# if defined(TN3270)
/*
* we can get EBADF if we were in transparent
* mode, and the transcom process died.
*/
if (errno == EBADF)
{
/*
* zero the bits (even though kernel does it)
* to make sure we are selecting on the right
* ones.
*/
memset (ibitsp, 0, fdsn);
memset (obitsp, 0, fdsn);
memset (xbitsp, 0, fdsn);
return 0;
}
# endif /* defined(TN3270) */
/* I don't like this, does it ever happen? */
printf ("sleep(5) from telnet, after select\r\n");
sleep (5);
}
return 0;
}
/*
* Any urgent data?
*/
if (FD_ISSET (net, xbitsp))
{
FD_CLR (net, xbitsp);
SYNCHing = 1;
(void) ttyflush (1); /* flush already enqueued data */
}
/*
* Something to read from the network...
*/
if (FD_ISSET (net, ibitsp))
{
int canread;
FD_CLR (net, ibitsp);
canread = ring_empty_consecutive (&netiring);
#if !defined(SO_OOBINLINE)
/*
* In 4.2 (and some early 4.3) systems, the
* OOB indication and data handling in the kernel
* is such that if two separate TCP Urgent requests
* come in, one byte of TCP data will be overlaid.
* This is fatal for Telnet, but we try to live
* with it.
*
* In addition, in 4.2 (and...), a special protocol
* is needed to pick up the TCP Urgent data in
* the correct sequence.
*
* What we do is: if we think we are in urgent
* mode, we look to see if we are "at the mark".
* If we are, we do an OOB receive. If we run
* this twice, we will do the OOB receive twice,
* but the second will fail, since the second
* time we were "at the mark", but there wasn't
* any data there (the kernel doesn't reset
* "at the mark" until we do a normal read).
* Once we've read the OOB data, we go ahead
* and do normal reads.
*
* There is also another problem, which is that
* since the OOB byte we read doesn't put us
* out of OOB state, and since that byte is most
* likely the TELNET DM (data mark), we would
* stay in the TELNET SYNCH (SYNCHing) state.
* So, clocks to the rescue. If we've "just"
* received a DM, then we test for the
* presence of OOB data when the receive OOB
* fails (and AFTER we did the normal mode read
* to clear "at the mark").
*/
if (SYNCHing)
{
int atmark;
static int bogus_oob = 0, first = 1;
ioctl (net, SIOCATMARK, (char *) &atmark);
if (atmark)
{
c = recv (net, netiring.supply, canread, MSG_OOB);
if ((c == -1) && (errno == EINVAL))
{
c = recv (net, netiring.supply, canread, 0);
if (clocks.didnetreceive < clocks.gotDM)
{
SYNCHing = stilloob (net);
}
}
else if (first && c > 0)
{
/*
* Bogosity check. Systems based on 4.2BSD
* do not return an error if you do a second
* recv(MSG_OOB). So, we do one. If it
* succeeds and returns exactly the same
* data, then assume that we are running
* on a broken system and set the bogus_oob
* flag. (If the data was different, then
* we probably got some valid new data, so
* increment the count...)
*/
int i;
i = recv (net, netiring.supply + c, canread - c, MSG_OOB);
if (i == c &&
memcmp (netiring.supply, netiring.supply + c, i) == 0)
{
bogus_oob = 1;
first = 0;
}
else if (i < 0)
{
bogus_oob = 0;
first = 0;
}
else
c += i;
}
if (bogus_oob && c > 0)
{
int i;
/*
* Bogosity. We have to do the read
* to clear the atmark to get out of
* an infinate loop.
*/
i = read (net, netiring.supply + c, canread - c);
if (i > 0)
c += i;
}
}
else
{
c = recv (net, netiring.supply, canread, 0);
}
}
else
{
c = recv (net, netiring.supply, canread, 0);
}
settimer (didnetreceive);
#else /* !defined(SO_OOBINLINE) */
c = recv (net, (char *) netiring.supply, canread, 0);
#endif /* !defined(SO_OOBINLINE) */
if (c < 0 && errno == EWOULDBLOCK)
{
c = 0;
}
else if (c <= 0)
{
return -1;
}
if (netdata)
{
Dump ('<', netiring.supply, c);
}
if (c)
ring_supplied (&netiring, c);
returnValue = 1;
}
/*
* Something to read from the tty...
*/
if (FD_ISSET (tin, ibitsp))
{
FD_CLR (tin, ibitsp);
c = TerminalRead (ttyiring.supply, ring_empty_consecutive (&ttyiring));
if (c < 0 && errno == EIO)
c = 0;
if (c < 0 && errno == EWOULDBLOCK)
{
c = 0;
}
else
{
/* EOF detection for line mode!!!! */
if ((c == 0) && MODE_LOCAL_CHARS (globalmode) && isatty (tin))
{
/* must be an EOF... */
*ttyiring.supply = termEofChar;
c = 1;
}
if (c <= 0)
{
return -1;
}
if (termdata)
{
Dump ('<', ttyiring.supply, c);
}
ring_supplied (&ttyiring, c);
}
returnValue = 1; /* did something useful */
}
if (FD_ISSET (net, obitsp))
{
FD_CLR (net, obitsp);
returnValue |= netflush ();
}
if (FD_ISSET (tout, obitsp))
{
FD_CLR (tout, obitsp);
returnValue |= (ttyflush (SYNCHing | flushout) > 0);
}
return returnValue;
}
