/* * Copyright (c) 1988, 1990, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if 0 #ifndef lint static const char sccsid[] = "@(#)sys_bsd.c 8.4 (Berkeley) 5/30/95"; #endif #endif #include /* * The following routines try to encapsulate what is system dependent * (at least between 4.x and dos) which is used in telnet.c. */ #include #include #include #include #include #include #include #include #include #include "arpa/telnet.h" #include "ring.h" #include "fdset.h" #include "defines.h" #include "externs.h" #include "types.h" #include "baud.h" int tout, /* Output file descriptor */ tin, /* Input file descriptor */ net; #ifndef USE_TERMIO struct tchars otc = { 0 }, ntc = { 0 }; struct ltchars oltc = { 0 }, nltc = { 0 }; struct sgttyb ottyb = { 0 }, nttyb = { 0 }; int olmode = 0; # define cfgetispeed(ptr) (ptr)->sg_ispeed # define cfgetospeed(ptr) (ptr)->sg_ospeed # define old_tc ottyb #else /* USE_TERMIO */ struct termio old_tc = { 0, 0, 0, 0, {}, 0, 0 }; # ifndef TCSANOW # ifdef TCSETS # define TCSANOW TCSETS # define TCSADRAIN TCSETSW # define tcgetattr(f, t) ioctl(f, TCGETS, (char *)t) # else # ifdef TCSETA # define TCSANOW TCSETA # define TCSADRAIN TCSETAW # define tcgetattr(f, t) ioctl(f, TCGETA, (char *)t) # else # define TCSANOW TIOCSETA # define TCSADRAIN TIOCSETAW # define tcgetattr(f, t) ioctl(f, TIOCGETA, (char *)t) # endif # endif # define tcsetattr(f, a, t) ioctl(f, a, (char *)t) # define cfgetospeed(ptr) ((ptr)->c_cflag&CBAUD) # ifdef CIBAUD # define cfgetispeed(ptr) (((ptr)->c_cflag&CIBAUD) >> IBSHIFT) # else # define cfgetispeed(ptr) cfgetospeed(ptr) # endif # endif /* TCSANOW */ # ifdef sysV88 # define TIOCFLUSH TC_PX_DRAIN # endif #endif /* USE_TERMIO */ static fd_set *ibitsp, *obitsp, *xbitsp; int fdsn; #ifdef SIGINT static SIG_FUNC_RET intr SIG_FUNC_PARMS(int); #endif /* SIGINT */ #ifdef SIGQUIT static SIG_FUNC_RET intr2 SIG_FUNC_PARMS(int); #endif /* SIGQUIT */ #ifdef SIGTSTP static SIG_FUNC_RET susp SIG_FUNC_PARMS(int); #endif /* SIGTSTP */ #ifdef SIGINFO static SIG_FUNC_RET ayt SIG_FUNC_PARMS(int); static SIG_FUNC_RET ayt_status_wrapper SIG_FUNC_PARMS(int); #endif void init_sys(void) { tout = fileno(stdout); tin = fileno(stdin); errno = 0; } int TerminalWrite(char *buf, int n) { return write(tout, buf, n); } int TerminalRead(char *buf, int n) { return read(tin, buf, n); } /* * */ int TerminalAutoFlush(void) { #if defined(LNOFLSH) int flush; ioctl(0, TIOCLGET, (char *)&flush); return !(flush&LNOFLSH); /* if LNOFLSH, no autoflush */ #else /* LNOFLSH */ return 1; #endif /* LNOFLSH */ } #ifdef KLUDGELINEMODE extern int kludgelinemode; #endif /* * TerminalSpecialChars() * * Look at an input character to see if it is a special character * and decide what to do. * * Output: * * 0 Don't add this character. * 1 Do add this character */ int TerminalSpecialChars(int c) { if (c == termIntChar) { intp(); return 0; } else if (c == termQuitChar) { #ifdef KLUDGELINEMODE if (kludgelinemode) sendbrk(); else #endif sendabort(); return 0; } else if (c == termEofChar) { if (my_want_state_is_will(TELOPT_LINEMODE)) { sendeof(); return 0; } return 1; } else if (c == termSuspChar) { sendsusp(); return(0); } else if (c == termFlushChar) { xmitAO(); /* Transmit Abort Output */ return 0; } else if (!MODE_LOCAL_CHARS(globalmode)) { if (c == termKillChar) { xmitEL(); return 0; } else if (c == termEraseChar) { xmitEC(); /* Transmit Erase Character */ return 0; } } return 1; } /* * Flush output to the terminal */ void TerminalFlushOutput(void) { #ifdef TIOCFLUSH (void) ioctl(fileno(stdout), TIOCFLUSH, (char *) 0); #else (void) ioctl(fileno(stdout), TCFLSH, (char *) 0); #endif } void TerminalSaveState(void) { #ifndef USE_TERMIO ioctl(0, TIOCGETP, (char *)&ottyb); ioctl(0, TIOCGETC, (char *)&otc); ioctl(0, TIOCGLTC, (char *)&oltc); ioctl(0, TIOCLGET, (char *)&olmode); ntc = otc; nltc = oltc; nttyb = ottyb; #else /* USE_TERMIO */ tcgetattr(0, &old_tc); new_tc = old_tc; #ifndef VDISCARD termFlushChar = CONTROL('O'); #endif #ifndef VWERASE termWerasChar = CONTROL('W'); #endif #ifndef VREPRINT termRprntChar = CONTROL('R'); #endif #ifndef VLNEXT termLiteralNextChar = CONTROL('V'); #endif #ifndef VSTART termStartChar = CONTROL('Q'); #endif #ifndef VSTOP termStopChar = CONTROL('S'); #endif #ifndef VSTATUS termAytChar = CONTROL('T'); #endif #endif /* USE_TERMIO */ } cc_t * tcval(int func) { switch(func) { case SLC_IP: return(&termIntChar); case SLC_ABORT: return(&termQuitChar); case SLC_EOF: return(&termEofChar); case SLC_EC: return(&termEraseChar); case SLC_EL: return(&termKillChar); case SLC_XON: return(&termStartChar); case SLC_XOFF: return(&termStopChar); case SLC_FORW1: return(&termForw1Char); #ifdef USE_TERMIO case SLC_FORW2: return(&termForw2Char); # ifdef VDISCARD case SLC_AO: return(&termFlushChar); # endif # ifdef VSUSP case SLC_SUSP: return(&termSuspChar); # endif # ifdef VWERASE case SLC_EW: return(&termWerasChar); # endif # ifdef VREPRINT case SLC_RP: return(&termRprntChar); # endif # ifdef VLNEXT case SLC_LNEXT: return(&termLiteralNextChar); # endif # ifdef VSTATUS case SLC_AYT: return(&termAytChar); # endif #endif case SLC_SYNCH: case SLC_BRK: case SLC_EOR: default: return((cc_t *)0); } } void TerminalDefaultChars(void) { #ifndef USE_TERMIO ntc = otc; nltc = oltc; nttyb.sg_kill = ottyb.sg_kill; nttyb.sg_erase = ottyb.sg_erase; #else /* USE_TERMIO */ memcpy(new_tc.c_cc, old_tc.c_cc, sizeof(old_tc.c_cc)); # ifndef VDISCARD termFlushChar = CONTROL('O'); # endif # ifndef VWERASE termWerasChar = CONTROL('W'); # endif # ifndef VREPRINT termRprntChar = CONTROL('R'); # endif # ifndef VLNEXT termLiteralNextChar = CONTROL('V'); # endif # ifndef VSTART termStartChar = CONTROL('Q'); # endif # ifndef VSTOP termStopChar = CONTROL('S'); # endif # ifndef VSTATUS termAytChar = CONTROL('T'); # endif #endif /* USE_TERMIO */ } /* * TerminalNewMode - set up terminal to a specific mode. * MODE_ECHO: do local terminal echo * MODE_FLOW: do local flow control * MODE_TRAPSIG: do local mapping to TELNET IAC sequences * MODE_EDIT: do local line editing * * Command mode: * MODE_ECHO|MODE_EDIT|MODE_FLOW|MODE_TRAPSIG * local echo * local editing * local xon/xoff * local signal mapping * * Linemode: * local/no editing * Both Linemode and Single Character mode: * local/remote echo * local/no xon/xoff * local/no signal mapping */ void TerminalNewMode(int f) { static int prevmode = 0; #ifndef USE_TERMIO struct tchars tc; struct ltchars ltc; struct sgttyb sb; int lmode; #else /* USE_TERMIO */ struct termio tmp_tc; #endif /* USE_TERMIO */ int onoff; int old; cc_t esc; globalmode = f&~MODE_FORCE; if (prevmode == f) return; /* * Write any outstanding data before switching modes * ttyflush() returns 0 only when there is no more data * left to write out, it returns -1 if it couldn't do * anything at all, otherwise it returns 1 + the number * of characters left to write. #ifndef USE_TERMIO * We would really like ask the kernel to wait for the output * to drain, like we can do with the TCSADRAIN, but we don't have * that option. The only ioctl that waits for the output to * drain, TIOCSETP, also flushes the input queue, which is NOT * what we want (TIOCSETP is like TCSADFLUSH). #endif */ old = ttyflush(SYNCHing|flushout); if (old < 0 || old > 1) { #ifdef USE_TERMIO tcgetattr(tin, &tmp_tc); #endif /* USE_TERMIO */ do { /* * Wait for data to drain, then flush again. */ #ifdef USE_TERMIO tcsetattr(tin, TCSADRAIN, &tmp_tc); #endif /* USE_TERMIO */ old = ttyflush(SYNCHing|flushout); } while (old < 0 || old > 1); } old = prevmode; prevmode = f&~MODE_FORCE; #ifndef USE_TERMIO sb = nttyb; tc = ntc; ltc = nltc; lmode = olmode; #else tmp_tc = new_tc; #endif if (f&MODE_ECHO) { #ifndef USE_TERMIO sb.sg_flags |= ECHO; #else tmp_tc.c_lflag |= ECHO; tmp_tc.c_oflag |= ONLCR; if (crlf) tmp_tc.c_iflag |= ICRNL; #endif } else { #ifndef USE_TERMIO sb.sg_flags &= ~ECHO; #else tmp_tc.c_lflag &= ~ECHO; tmp_tc.c_oflag &= ~ONLCR; #endif } if ((f&MODE_FLOW) == 0) { #ifndef USE_TERMIO tc.t_startc = _POSIX_VDISABLE; tc.t_stopc = _POSIX_VDISABLE; #else tmp_tc.c_iflag &= ~(IXOFF|IXON); /* Leave the IXANY bit alone */ } else { if (restartany < 0) { tmp_tc.c_iflag |= IXOFF|IXON; /* Leave the IXANY bit alone */ } else if (restartany > 0) { tmp_tc.c_iflag |= IXOFF|IXON|IXANY; } else { tmp_tc.c_iflag |= IXOFF|IXON; tmp_tc.c_iflag &= ~IXANY; } #endif } if ((f&MODE_TRAPSIG) == 0) { #ifndef USE_TERMIO tc.t_intrc = _POSIX_VDISABLE; tc.t_quitc = _POSIX_VDISABLE; tc.t_eofc = _POSIX_VDISABLE; ltc.t_suspc = _POSIX_VDISABLE; ltc.t_dsuspc = _POSIX_VDISABLE; #else tmp_tc.c_lflag &= ~ISIG; #endif localchars = 0; } else { #ifdef USE_TERMIO tmp_tc.c_lflag |= ISIG; #endif localchars = 1; } if (f&MODE_EDIT) { #ifndef USE_TERMIO sb.sg_flags &= ~CBREAK; sb.sg_flags |= CRMOD; #else tmp_tc.c_lflag |= ICANON; #endif } else { #ifndef USE_TERMIO sb.sg_flags |= CBREAK; if (f&MODE_ECHO) sb.sg_flags |= CRMOD; else sb.sg_flags &= ~CRMOD; #else tmp_tc.c_lflag &= ~ICANON; tmp_tc.c_iflag &= ~ICRNL; tmp_tc.c_cc[VMIN] = 1; tmp_tc.c_cc[VTIME] = 0; #endif } if ((f&(MODE_EDIT|MODE_TRAPSIG)) == 0) { #ifndef USE_TERMIO ltc.t_lnextc = _POSIX_VDISABLE; #else # ifdef VLNEXT tmp_tc.c_cc[VLNEXT] = (cc_t)(_POSIX_VDISABLE); # endif #endif } if (f&MODE_SOFT_TAB) { #ifndef USE_TERMIO sb.sg_flags |= XTABS; #else # ifdef OXTABS tmp_tc.c_oflag |= OXTABS; # endif # ifdef TABDLY tmp_tc.c_oflag &= ~TABDLY; tmp_tc.c_oflag |= TAB3; # endif #endif } else { #ifndef USE_TERMIO sb.sg_flags &= ~XTABS; #else # ifdef OXTABS tmp_tc.c_oflag &= ~OXTABS; # endif # ifdef TABDLY tmp_tc.c_oflag &= ~TABDLY; # endif #endif } if (f&MODE_LIT_ECHO) { #ifndef USE_TERMIO lmode &= ~LCTLECH; #else # ifdef ECHOCTL tmp_tc.c_lflag &= ~ECHOCTL; # endif #endif } else { #ifndef USE_TERMIO lmode |= LCTLECH; #else # ifdef ECHOCTL tmp_tc.c_lflag |= ECHOCTL; # endif #endif } if (f == -1) { onoff = 0; } else { #ifndef USE_TERMIO if (f & MODE_OUTBIN) lmode |= LLITOUT; else lmode &= ~LLITOUT; if (f & MODE_INBIN) lmode |= LPASS8; else lmode &= ~LPASS8; #else if (f & MODE_INBIN) tmp_tc.c_iflag &= ~ISTRIP; else tmp_tc.c_iflag |= ISTRIP; if (f & MODE_OUTBIN) { tmp_tc.c_cflag &= ~(CSIZE|PARENB); tmp_tc.c_cflag |= CS8; tmp_tc.c_oflag &= ~OPOST; } else { tmp_tc.c_cflag &= ~(CSIZE|PARENB); tmp_tc.c_cflag |= old_tc.c_cflag & (CSIZE|PARENB); tmp_tc.c_oflag |= OPOST; } #endif onoff = 1; } if (f != -1) { #ifdef SIGINT (void) signal(SIGINT, intr); #endif #ifdef SIGQUIT (void) signal(SIGQUIT, intr2); #endif #ifdef SIGTSTP (void) signal(SIGTSTP, susp); #endif /* SIGTSTP */ #ifdef SIGINFO (void) signal(SIGINFO, ayt); #endif #if defined(USE_TERMIO) && defined(NOKERNINFO) tmp_tc.c_lflag |= NOKERNINFO; #endif /* * We don't want to process ^Y here. It's just another * character that we'll pass on to the back end. It has * to process it because it will be processed when the * user attempts to read it, not when we send it. */ #ifndef USE_TERMIO ltc.t_dsuspc = _POSIX_VDISABLE; #else # ifdef VDSUSP tmp_tc.c_cc[VDSUSP] = (cc_t)(_POSIX_VDISABLE); # endif #endif #ifdef USE_TERMIO /* * If the VEOL character is already set, then use VEOL2, * otherwise use VEOL. */ esc = (rlogin != _POSIX_VDISABLE) ? rlogin : escape; if ((tmp_tc.c_cc[VEOL] != esc) # ifdef VEOL2 && (tmp_tc.c_cc[VEOL2] != esc) # endif ) { if (tmp_tc.c_cc[VEOL] == (cc_t)(_POSIX_VDISABLE)) tmp_tc.c_cc[VEOL] = esc; # ifdef VEOL2 else if (tmp_tc.c_cc[VEOL2] == (cc_t)(_POSIX_VDISABLE)) tmp_tc.c_cc[VEOL2] = esc; # endif } #else if (tc.t_brkc == (cc_t)(_POSIX_VDISABLE)) tc.t_brkc = esc; #endif } else { #ifdef SIGINFO (void) signal(SIGINFO, ayt_status_wrapper); #endif #ifdef SIGINT (void) signal(SIGINT, SIG_DFL); #endif #ifdef SIGQUIT (void) signal(SIGQUIT, SIG_DFL); #endif #ifdef SIGTSTP (void) signal(SIGTSTP, SIG_DFL); # ifndef SOLARIS (void) sigsetmask(sigblock(0) & ~(1<<(SIGTSTP-1))); # else /* SOLARIS */ (void) sigrelse(SIGTSTP); # endif /* SOLARIS */ #endif /* SIGTSTP */ #ifndef USE_TERMIO ltc = oltc; tc = otc; sb = ottyb; lmode = olmode; #else tmp_tc = old_tc; #endif } #ifndef USE_TERMIO ioctl(tin, TIOCLSET, (char *)&lmode); ioctl(tin, TIOCSLTC, (char *)<c); ioctl(tin, TIOCSETC, (char *)&tc); ioctl(tin, TIOCSETN, (char *)&sb); #else if (tcsetattr(tin, TCSADRAIN, &tmp_tc) < 0) tcsetattr(tin, TCSANOW, &tmp_tc); #endif ioctl(tin, FIONBIO, (char *)&onoff); ioctl(tout, FIONBIO, (char *)&onoff); } void TerminalSpeeds(long *ispeed, long *ospeed) { #ifdef DECODE_BAUD struct termspeeds *tp; #endif /* DECODE_BAUD */ long in, out; out = cfgetospeed(&old_tc); in = cfgetispeed(&old_tc); if (in == 0) in = out; #ifdef DECODE_BAUD tp = termspeeds; while ((tp->speed != -1) && (tp->value < in)) tp++; *ispeed = tp->speed; tp = termspeeds; while ((tp->speed != -1) && (tp->value < out)) tp++; *ospeed = tp->speed; #else /* DECODE_BAUD */ *ispeed = in; *ospeed = out; #endif /* DECODE_BAUD */ } int TerminalWindowSize(long *rows, long *cols) { #ifdef TIOCGWINSZ struct winsize ws; if (ioctl(fileno(stdin), TIOCGWINSZ, (char *)&ws) >= 0) { *rows = ws.ws_row; *cols = ws.ws_col; return 1; } #endif /* TIOCGWINSZ */ return 0; } int NetClose(int fd) { return close(fd); } static void NetNonblockingIO(int fd, int onoff) { ioctl(fd, FIONBIO, (char *)&onoff); } /* * Various signal handling routines. */ /* ARGSUSED */ SIG_FUNC_RET intr SIG_FUNC_PARMS(int sig __unused) { if (localchars) { intp(); return; } setcommandmode(); longjmp(toplevel, -1); } /* ARGSUSED */ SIG_FUNC_RET intr2 SIG_FUNC_PARMS(int sig __unused) { if (localchars) { #ifdef KLUDGELINEMODE if (kludgelinemode) sendbrk(); else #endif sendabort(); return; } } #ifdef SIGTSTP /* ARGSUSED */ SIG_FUNC_RET susp SIG_FUNC_PARMS(int sig __unused) { if ((rlogin != _POSIX_VDISABLE) && rlogin_susp()) return; if (localchars) sendsusp(); } #endif #ifdef SIGWINCH /* ARGSUSED */ static SIG_FUNC_RET sendwin SIG_FUNC_PARMS(int sig __unused) { if (connected) { sendnaws(); } } #endif #ifdef SIGINFO /* ARGSUSED */ SIG_FUNC_RET ayt SIG_FUNC_PARMS(int sig __unused) { if (connected) sendayt(); else ayt_status(); } #endif #ifdef SIGINFO SIG_FUNC_RET ayt_status_wrapper SIG_FUNC_PARMS(int sig __unused) { ayt_status(); } #endif void sys_telnet_init(void) { (void) signal(SIGINT, intr); (void) signal(SIGQUIT, intr2); (void) signal(SIGPIPE, SIG_IGN); #ifdef SIGWINCH (void) signal(SIGWINCH, sendwin); #endif #ifdef SIGTSTP (void) signal(SIGTSTP, susp); #endif #ifdef SIGINFO (void) signal(SIGINFO, ayt); #endif setconnmode(0); NetNonblockingIO(net, 1); #if defined(SO_OOBINLINE) if (SetSockOpt(net, SOL_SOCKET, SO_OOBINLINE, 1) == -1) { perror("SetSockOpt"); } #endif /* defined(SO_OOBINLINE) */ } /* * Process rings - * * This routine tries to fill up/empty our various rings. * * The parameter specifies whether this is a poll operation, * or a block-until-something-happens operation. * * The return value is 1 if something happened, 0 if not. */ int process_rings(int netin, int netout, int netex, int ttyin, int ttyout, int poll) { int c; 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; } /* I don't like this, does it ever happen? */ printf("sleep(5) from telnet, after select: %s\r\n", strerror(errno)); 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; }