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Diffstat (limited to 'crypto/telnet/telnetd/slc.c')
| -rw-r--r-- | crypto/telnet/telnetd/slc.c | 491 |
1 files changed, 491 insertions, 0 deletions
diff --git a/crypto/telnet/telnetd/slc.c b/crypto/telnet/telnetd/slc.c new file mode 100644 index 000000000000..6cbb7ababa1b --- /dev/null +++ b/crypto/telnet/telnetd/slc.c @@ -0,0 +1,491 @@ +/* + * Copyright (c) 1989, 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. + */ + +#ifndef lint +static char sccsid[] = "@(#)slc.c 8.2 (Berkeley) 5/30/95"; +#endif /* not lint */ + +#include "telnetd.h" + +#ifdef LINEMODE +/* + * local varibles + */ +static unsigned char *def_slcbuf = (unsigned char *)0; +static int def_slclen = 0; +static int slcchange; /* change to slc is requested */ +static unsigned char *slcptr; /* pointer into slc buffer */ +static unsigned char slcbuf[NSLC*6]; /* buffer for slc negotiation */ + +/* + * send_slc + * + * Write out the current special characters to the client. + */ + void +send_slc() +{ + register int i; + + /* + * Send out list of triplets of special characters + * to client. We only send info on the characters + * that are currently supported. + */ + for (i = 1; i <= NSLC; i++) { + if ((slctab[i].defset.flag & SLC_LEVELBITS) == SLC_NOSUPPORT) + continue; + add_slc((unsigned char)i, slctab[i].current.flag, + slctab[i].current.val); + } + +} /* end of send_slc */ + +/* + * default_slc + * + * Set pty special characters to all the defaults. + */ + void +default_slc() +{ + register int i; + + for (i = 1; i <= NSLC; i++) { + slctab[i].current.val = slctab[i].defset.val; + if (slctab[i].current.val == (cc_t)(_POSIX_VDISABLE)) + slctab[i].current.flag = SLC_NOSUPPORT; + else + slctab[i].current.flag = slctab[i].defset.flag; + if (slctab[i].sptr) { + *(slctab[i].sptr) = slctab[i].defset.val; + } + } + slcchange = 1; + +} /* end of default_slc */ +#endif /* LINEMODE */ + +/* + * get_slc_defaults + * + * Initialize the slc mapping table. + */ + void +get_slc_defaults() +{ + register int i; + + init_termbuf(); + + for (i = 1; i <= NSLC; i++) { + slctab[i].defset.flag = + spcset(i, &slctab[i].defset.val, &slctab[i].sptr); + slctab[i].current.flag = SLC_NOSUPPORT; + slctab[i].current.val = 0; + } + +} /* end of get_slc_defaults */ + +#ifdef LINEMODE +/* + * add_slc + * + * Add an slc triplet to the slc buffer. + */ + void +add_slc(func, flag, val) + register char func, flag; + register cc_t val; +{ + + if ((*slcptr++ = (unsigned char)func) == 0xff) + *slcptr++ = 0xff; + + if ((*slcptr++ = (unsigned char)flag) == 0xff) + *slcptr++ = 0xff; + + if ((*slcptr++ = (unsigned char)val) == 0xff) + *slcptr++ = 0xff; + +} /* end of add_slc */ + +/* + * start_slc + * + * Get ready to process incoming slc's and respond to them. + * + * The parameter getit is non-zero if it is necessary to grab a copy + * of the terminal control structures. + */ + void +start_slc(getit) + register int getit; +{ + + slcchange = 0; + if (getit) + init_termbuf(); + (void) sprintf((char *)slcbuf, "%c%c%c%c", + IAC, SB, TELOPT_LINEMODE, LM_SLC); + slcptr = slcbuf + 4; + +} /* end of start_slc */ + +/* + * end_slc + * + * Finish up the slc negotiation. If something to send, then send it. + */ + int +end_slc(bufp) + register unsigned char **bufp; +{ + register int len; + void netflush(); + + /* + * If a change has occured, store the new terminal control + * structures back to the terminal driver. + */ + if (slcchange) { + set_termbuf(); + } + + /* + * If the pty state has not yet been fully processed and there is a + * deferred slc request from the client, then do not send any + * sort of slc negotiation now. We will respond to the client's + * request very soon. + */ + if (def_slcbuf && (terminit() == 0)) { + return(0); + } + + if (slcptr > (slcbuf + 4)) { + if (bufp) { + *bufp = &slcbuf[4]; + return(slcptr - slcbuf - 4); + } else { + (void) sprintf((char *)slcptr, "%c%c", IAC, SE); + slcptr += 2; + len = slcptr - slcbuf; + writenet(slcbuf, len); + netflush(); /* force it out immediately */ + DIAG(TD_OPTIONS, printsub('>', slcbuf+2, len-2);); + } + } + return (0); + +} /* end of end_slc */ + +/* + * process_slc + * + * Figure out what to do about the client's slc + */ + void +process_slc(func, flag, val) + register unsigned char func, flag; + register cc_t val; +{ + register int hislevel, mylevel, ack; + + /* + * Ensure that we know something about this function + */ + if (func > NSLC) { + add_slc(func, SLC_NOSUPPORT, 0); + return; + } + + /* + * Process the special case requests of 0 SLC_DEFAULT 0 + * and 0 SLC_VARIABLE 0. Be a little forgiving here, don't + * worry about whether the value is actually 0 or not. + */ + if (func == 0) { + if ((flag = flag & SLC_LEVELBITS) == SLC_DEFAULT) { + default_slc(); + send_slc(); + } else if (flag == SLC_VARIABLE) { + send_slc(); + } + return; + } + + /* + * Appears to be a function that we know something about. So + * get on with it and see what we know. + */ + + hislevel = flag & SLC_LEVELBITS; + mylevel = slctab[func].current.flag & SLC_LEVELBITS; + ack = flag & SLC_ACK; + /* + * ignore the command if: + * the function value and level are the same as what we already have; + * or the level is the same and the ack bit is set + */ + if (hislevel == mylevel && (val == slctab[func].current.val || ack)) { + return; + } else if (ack) { + /* + * If we get here, we got an ack, but the levels don't match. + * This shouldn't happen. If it does, it is probably because + * we have sent two requests to set a variable without getting + * a response between them, and this is the first response. + * So, ignore it, and wait for the next response. + */ + return; + } else { + change_slc(func, flag, val); + } + +} /* end of process_slc */ + +/* + * change_slc + * + * Process a request to change one of our special characters. + * Compare client's request with what we are capable of supporting. + */ + void +change_slc(func, flag, val) + register char func, flag; + register cc_t val; +{ + register int hislevel, mylevel; + + hislevel = flag & SLC_LEVELBITS; + mylevel = slctab[func].defset.flag & SLC_LEVELBITS; + /* + * If client is setting a function to NOSUPPORT + * or DEFAULT, then we can easily and directly + * accomodate the request. + */ + if (hislevel == SLC_NOSUPPORT) { + slctab[func].current.flag = flag; + slctab[func].current.val = (cc_t)_POSIX_VDISABLE; + flag |= SLC_ACK; + add_slc(func, flag, val); + return; + } + if (hislevel == SLC_DEFAULT) { + /* + * Special case here. If client tells us to use + * the default on a function we don't support, then + * return NOSUPPORT instead of what we may have as a + * default level of DEFAULT. + */ + if (mylevel == SLC_DEFAULT) { + slctab[func].current.flag = SLC_NOSUPPORT; + } else { + slctab[func].current.flag = slctab[func].defset.flag; + } + slctab[func].current.val = slctab[func].defset.val; + add_slc(func, slctab[func].current.flag, + slctab[func].current.val); + return; + } + + /* + * Client wants us to change to a new value or he + * is telling us that he can't change to our value. + * Some of the slc's we support and can change, + * some we do support but can't change, + * and others we don't support at all. + * If we can change it then we have a pointer to + * the place to put the new value, so change it, + * otherwise, continue the negotiation. + */ + if (slctab[func].sptr) { + /* + * We can change this one. + */ + slctab[func].current.val = val; + *(slctab[func].sptr) = val; + slctab[func].current.flag = flag; + flag |= SLC_ACK; + slcchange = 1; + add_slc(func, flag, val); + } else { + /* + * It is not possible for us to support this + * request as he asks. + * + * If our level is DEFAULT, then just ack whatever was + * sent. + * + * If he can't change and we can't change, + * then degenerate to NOSUPPORT. + * + * Otherwise we send our level back to him, (CANTCHANGE + * or NOSUPPORT) and if CANTCHANGE, send + * our value as well. + */ + if (mylevel == SLC_DEFAULT) { + slctab[func].current.flag = flag; + slctab[func].current.val = val; + flag |= SLC_ACK; + } else if (hislevel == SLC_CANTCHANGE && + mylevel == SLC_CANTCHANGE) { + flag &= ~SLC_LEVELBITS; + flag |= SLC_NOSUPPORT; + slctab[func].current.flag = flag; + } else { + flag &= ~SLC_LEVELBITS; + flag |= mylevel; + slctab[func].current.flag = flag; + if (mylevel == SLC_CANTCHANGE) { + slctab[func].current.val = + slctab[func].defset.val; + val = slctab[func].current.val; + } + } + add_slc(func, flag, val); + } + +} /* end of change_slc */ + +#if defined(USE_TERMIO) && (VEOF == VMIN) +cc_t oldeofc = '\004'; +#endif + +/* + * check_slc + * + * Check the special characters in use and notify the client if any have + * changed. Only those characters that are capable of being changed are + * likely to have changed. If a local change occurs, kick the support level + * and flags up to the defaults. + */ + void +check_slc() +{ + register int i; + + for (i = 1; i <= NSLC; i++) { +#if defined(USE_TERMIO) && (VEOF == VMIN) + /* + * In a perfect world this would be a neat little + * function. But in this world, we should not notify + * client of changes to the VEOF char when + * ICANON is off, because it is not representing + * a special character. + */ + if (i == SLC_EOF) { + if (!tty_isediting()) + continue; + else if (slctab[i].sptr) + oldeofc = *(slctab[i].sptr); + } +#endif /* defined(USE_TERMIO) && defined(SYSV_TERMIO) */ + if (slctab[i].sptr && + (*(slctab[i].sptr) != slctab[i].current.val)) { + slctab[i].current.val = *(slctab[i].sptr); + if (*(slctab[i].sptr) == (cc_t)_POSIX_VDISABLE) + slctab[i].current.flag = SLC_NOSUPPORT; + else + slctab[i].current.flag = slctab[i].defset.flag; + add_slc((unsigned char)i, slctab[i].current.flag, + slctab[i].current.val); + } + } +} /* check_slc */ + +/* + * do_opt_slc + * + * Process an slc option buffer. Defer processing of incoming slc's + * until after the terminal state has been processed. Save the first slc + * request that comes along, but discard all others. + * + * ptr points to the beginning of the buffer, len is the length. + */ + void +do_opt_slc(ptr, len) + register unsigned char *ptr; + register int len; +{ + register unsigned char func, flag; + cc_t val; + register unsigned char *end = ptr + len; + + if (terminit()) { /* go ahead */ + while (ptr < end) { + func = *ptr++; + if (ptr >= end) break; + flag = *ptr++; + if (ptr >= end) break; + val = (cc_t)*ptr++; + + process_slc(func, flag, val); + + } + } else { + /* + * save this slc buffer if it is the first, otherwise dump + * it. + */ + if (def_slcbuf == (unsigned char *)0) { + def_slclen = len; + def_slcbuf = (unsigned char *)malloc((unsigned)len); + if (def_slcbuf == (unsigned char *)0) + return; /* too bad */ + memmove(def_slcbuf, ptr, len); + } + } + +} /* end of do_opt_slc */ + +/* + * deferslc + * + * Do slc stuff that was deferred. + */ + void +deferslc() +{ + if (def_slcbuf) { + start_slc(1); + do_opt_slc(def_slcbuf, def_slclen); + (void) end_slc(0); + free(def_slcbuf); + def_slcbuf = (unsigned char *)0; + def_slclen = 0; + } + +} /* end of deferslc */ + +#endif /* LINEMODE */ |