2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)utility.c 8.4 (Berkeley) 5/30/95
30 * $FreeBSD: src/crypto/telnet/telnetd/utility.c,v 1.5.2.4 2002/04/13 10:59:09 markm Exp $
35 #include <sys/utsname.h>
42 #include <libtelnet/auth.h>
45 #include <libtelnet/encrypt.h>
49 * utility functions performing io related tasks
55 * A small subroutine to flush the network output buffer, get some data
56 * from the network, and pass it through the telnet state machine. We
57 * also flush the pty input buffer (by dropping its data) if it becomes
65 DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
66 if (nfrontp - nbackp > 0) {
69 ncc = read(net, netibuf, sizeof netibuf);
71 syslog(LOG_INFO, "ttloop: read: %m");
73 } else if (ncc == 0) {
74 syslog(LOG_INFO, "ttloop: peer died: %m");
77 DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
79 telrcv(); /* state machine */
81 pfrontp = pbackp = ptyobuf;
87 * Check a descriptor to see if out of band data exists on it.
92 static struct timeval timeout = { 0, 0 };
99 memset((char *)&timeout, 0, sizeof timeout);
100 value = select(s+1, NULL, NULL, &excepts, &timeout);
101 } while ((value == -1) && (errno == EINTR));
104 fatalperror(pty, "select");
106 if (FD_ISSET(s, &excepts)) {
118 if ((n = pfrontp - pbackp) > 0) {
119 DIAG(TD_REPORT | TD_PTYDATA,
120 output_data("td: ptyflush %d chars\r\n", n));
121 DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
122 n = write(pty, pbackp, n);
125 if (errno == EWOULDBLOCK || errno == EINTR)
130 if (pbackp == pfrontp)
131 pbackp = pfrontp = ptyobuf;
137 * Return the address of the next "item" in the TELNET data
138 * stream. This will be the address of the next character if
139 * the current address is a user data character, or it will
140 * be the address of the character following the TELNET command
141 * if the current address is a TELNET IAC ("I Am a Command")
145 nextitem(char *current)
147 if ((*current&0xff) != IAC) {
150 switch (*(current+1)&0xff) {
156 case SB: /* loop forever looking for the SE */
158 char *look = current+2;
161 if ((*look++&0xff) == IAC) {
162 if ((*look++&0xff) == SE) {
171 } /* end of nextitem */
176 * We are about to do a TELNET SYNCH operation. Clear
177 * the path to the network.
179 * Things are a bit tricky since we may have sent the first
180 * byte or so of a previous TELNET command into the network.
181 * So, we have to scan the network buffer from the beginning
182 * until we are up to where we want to be.
184 * A side effect of what we do, just to keep things
185 * simple, is to clear the urgent data pointer. The principal
186 * caller should be setting the urgent data pointer AFTER calling
192 char *thisitem, *next;
194 #define wewant(p) ((nfrontp > p) && ((*p&0xff) == IAC) && \
195 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
198 thisitem = nclearto > netobuf ? nclearto : netobuf;
199 #else /* ENCRYPTION */
201 #endif /* ENCRYPTION */
203 while ((next = nextitem(thisitem)) <= nbackp) {
207 /* Now, thisitem is first before/at boundary. */
210 good = nclearto > netobuf ? nclearto : netobuf;
211 #else /* ENCRYPTION */
212 good = netobuf; /* where the good bytes go */
213 #endif /* ENCRYPTION */
215 while (nfrontp > thisitem) {
216 if (wewant(thisitem)) {
221 next = nextitem(next);
222 } while (wewant(next) && (nfrontp > next));
223 length = next-thisitem;
224 memmove(good, thisitem, length);
228 thisitem = nextitem(thisitem);
233 nfrontp = good; /* next byte to be sent */
235 } /* end of netclear */
239 * Send as much data as possible to the network,
240 * handling requests for urgent data.
248 while ((n = nfrontp - nbackp) > 0) {
250 /* XXX This causes output_data() to recurse and die */
252 n += output_data("td: netflush %d chars\r\n", n);
256 if (encrypt_output) {
257 char *s = nclearto ? nclearto : nbackp;
258 if (nfrontp - s > 0) {
259 (*encrypt_output)((unsigned char *)s, nfrontp-s);
263 #endif /* ENCRYPTION */
265 * if no urgent data, or if the other side appears to be an
266 * old 4.2 client (and thus unable to survive TCP urgent data),
267 * write the entire buffer in non-OOB mode.
269 if ((neturg == 0) || (not42 == 0)) {
270 n = write(net, nbackp, n); /* normal write */
274 * In 4.2 (and 4.3) systems, there is some question about
275 * what byte in a sendOOB operation is the "OOB" data.
276 * To make ourselves compatible, we only send ONE byte
277 * out of band, the one WE THINK should be OOB (though
278 * we really have more the TCP philosophy of urgent data
279 * rather than the Unix philosophy of OOB data).
282 n = send(net, nbackp, n-1, 0); /* send URGENT all by itself */
284 n = send(net, nbackp, n, MSG_OOB); /* URGENT data */
288 if (errno == EWOULDBLOCK || errno == EINTR)
295 if (nbackp > nclearto)
297 #endif /* ENCRYPTION */
298 if (nbackp >= neturg) {
301 if (nbackp == nfrontp) {
302 nbackp = nfrontp = netobuf;
305 #endif /* ENCRYPTION */
309 } /* end of netflush */
313 * miscellaneous functions doing a variety of little jobs follow ...
318 fatal(int f, const char *msg)
322 (void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
324 if (encrypt_output) {
326 * Better turn off encryption first....
332 #endif /* ENCRYPTION */
333 (void) write(f, buf, (int)strlen(buf));
339 fatalperror(int f, const char *msg)
343 (void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
350 edithost(char *pat, char *host)
352 char *res = editedhost;
373 if (res == &editedhost[sizeof editedhost - 1]) {
380 (void) strncpy(res, host,
381 sizeof editedhost - (res - editedhost) -1);
384 editedhost[sizeof editedhost - 1] = '\0';
387 static char *putlocation;
390 putstr(const char *s)
404 static char fmtstr[] = { "%+" };
406 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
410 putf(char *cp, char *where)
416 static struct utsname kerninfo;
418 if (!*kerninfo.sysname)
429 } else if (*cp != '%') {
437 /* names are like /dev/pts/2 -- we want pts/2 */
438 slash = strchr(line+1, '/');
440 slash = strrchr(line, '/');
442 if (slash == (char *) 0)
454 setlocale(LC_TIME, "");
457 (void)strftime(db, sizeof(db), fmtstr, localtime(&t));
463 putstr(kerninfo.sysname);
467 putstr(kerninfo.machine);
471 putstr(kerninfo.release);
475 putstr(kerninfo.version);
489 * Print telnet options and commands in plain text, if possible.
492 printoption(const char *fmt, int option)
494 if (TELOPT_OK(option))
495 output_data("%s %s\r\n", fmt, TELOPT(option));
496 else if (TELCMD_OK(option))
497 output_data("%s %s\r\n", fmt, TELCMD(option));
499 output_data("%s %d\r\n", fmt, option);
504 printsub(char direction, unsigned char *pointer, int length)
508 if (!(diagnostic & TD_OPTIONS))
512 output_data("td: %s suboption ",
513 direction == '<' ? "recv" : "send");
517 i = pointer[length-2];
518 j = pointer[length-1];
520 if (i != IAC || j != SE) {
521 output_data("(terminated by ");
523 output_data("%s ", TELOPT(i));
524 else if (TELCMD_OK(i))
525 output_data("%s ", TELCMD(i));
527 output_data("%d ", i);
529 output_data("%s", TELOPT(j));
530 else if (TELCMD_OK(j))
531 output_data("%s", TELCMD(j));
533 output_data("%d", j);
534 output_data(", not IAC SE!) ");
540 output_data("(Empty suboption??\?)");
543 switch (pointer[0]) {
545 output_data("TERMINAL-TYPE ");
546 switch (pointer[1]) {
548 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
555 "- unknown qualifier %d (0x%x).",
556 pointer[1], pointer[1]);
560 output_data("TERMINAL-SPEED");
562 output_data(" (empty suboption??\?)");
565 switch (pointer[1]) {
567 output_data(" IS %.*s", length-2, (char *)pointer+2);
571 output_data(" SEND");
573 output_data(" %d (unknown)", pointer[1]);
574 for (i = 2; i < length; i++) {
575 output_data(" ?%d?", pointer[i]);
582 output_data("TOGGLE-FLOW-CONTROL");
584 output_data(" (empty suboption??\?)");
587 switch (pointer[1]) {
589 output_data(" OFF"); break;
591 output_data(" ON"); break;
592 case LFLOW_RESTART_ANY:
593 output_data(" RESTART-ANY"); break;
594 case LFLOW_RESTART_XON:
595 output_data(" RESTART-XON"); break;
597 output_data(" %d (unknown)", pointer[1]);
599 for (i = 2; i < length; i++) {
600 output_data(" ?%d?", pointer[i]);
607 output_data(" (empty suboption??\?)");
611 output_data(" ?%d?", pointer[1]);
614 output_data(" %d %d (%d)",
615 pointer[1], pointer[2],
616 (int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
618 output_data(" ?%d?", pointer[3]);
621 output_data(" %d %d (%d)",
622 pointer[3], pointer[4],
623 (int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
624 for (i = 5; i < length; i++) {
625 output_data(" ?%d?", pointer[i]);
629 case TELOPT_LINEMODE:
630 output_data("LINEMODE ");
632 output_data(" (empty suboption??\?)");
635 switch (pointer[1]) {
637 output_data("WILL ");
640 output_data("WONT ");
646 output_data("DONT ");
649 output_data("(no option??\?)");
652 switch (pointer[2]) {
654 output_data("Forward Mask");
655 for (i = 3; i < length; i++) {
656 output_data(" %x", pointer[i]);
660 output_data("%d (unknown)", pointer[2]);
661 for (i = 3; i < length; i++) {
662 output_data(" %d", pointer[i]);
670 for (i = 2; i < length - 2; i += 3) {
671 if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
672 output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
674 output_data(" %d", pointer[i+SLC_FUNC]);
675 switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
677 output_data(" NOSUPPORT"); break;
679 output_data(" CANTCHANGE"); break;
681 output_data(" VARIABLE"); break;
683 output_data(" DEFAULT"); break;
685 output_data("%s%s%s",
686 pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
687 pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
688 pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
689 if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
690 SLC_FLUSHOUT| SLC_LEVELBITS)) {
691 output_data("(0x%x)", pointer[i+SLC_FLAGS]);
693 output_data(" %d;", pointer[i+SLC_VALUE]);
694 if ((pointer[i+SLC_VALUE] == IAC) &&
695 (pointer[i+SLC_VALUE+1] == IAC))
698 for (; i < length; i++) {
699 output_data(" ?%d?", pointer[i]);
704 output_data("MODE ");
706 output_data("(no mode??\?)");
711 sprintf(tbuf, "%s%s%s%s%s",
712 pointer[2]&MODE_EDIT ? "|EDIT" : "",
713 pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
714 pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
715 pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
716 pointer[2]&MODE_ACK ? "|ACK" : "");
717 output_data("%s", tbuf[1] ? &tbuf[1] : "0");
719 if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
720 output_data(" (0x%x)", pointer[2]);
722 for (i = 3; i < length; i++) {
723 output_data(" ?0x%x?", pointer[i]);
727 output_data("%d (unknown)", pointer[1]);
728 for (i = 2; i < length; i++) {
729 output_data(" %d", pointer[i]);
734 case TELOPT_STATUS: {
738 output_data("STATUS");
740 switch (pointer[1]) {
742 if (pointer[1] == TELQUAL_SEND)
743 output_data(" SEND");
745 output_data(" %d (unknown)", pointer[1]);
746 for (i = 2; i < length; i++) {
747 output_data(" ?%d?", pointer[i]);
751 output_data(" IS\r\n");
753 for (i = 2; i < length; i++) {
755 case DO: cp = "DO"; goto common2;
756 case DONT: cp = "DONT"; goto common2;
757 case WILL: cp = "WILL"; goto common2;
758 case WONT: cp = "WONT"; goto common2;
761 if (TELOPT_OK(pointer[i]))
762 output_data(" %s %s", cp, TELOPT(pointer[i]));
764 output_data(" %s %d", cp, pointer[i]);
774 if (pointer[j] == SE) {
777 if (pointer[j+1] == SE)
782 pointer[k++] = pointer[j++];
784 printsub(0, &pointer[i], k - i);
796 output_data(" %d", pointer[i]);
805 case TELOPT_XDISPLOC:
806 output_data("X-DISPLAY-LOCATION ");
807 switch (pointer[1]) {
809 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
815 output_data("- unknown qualifier %d (0x%x).",
816 pointer[1], pointer[1]);
820 case TELOPT_NEW_ENVIRON:
821 output_data("NEW-ENVIRON ");
823 case TELOPT_OLD_ENVIRON:
824 output_data("OLD-ENVIRON");
826 switch (pointer[1]) {
831 output_data("SEND ");
834 output_data("INFO ");
838 for (i = 2; i < length; i++ ) {
839 switch (pointer[i]) {
841 output_data("\" VAR " + noquote);
846 output_data("\" VALUE " + noquote);
851 output_data("\" ESC " + noquote);
856 output_data("\" USERVAR " + noquote);
861 if (isprint(pointer[i]) && pointer[i] != '"') {
866 output_data("%c", pointer[i]);
868 output_data("\" %03o " + noquote,
882 #ifdef AUTHENTICATION
883 case TELOPT_AUTHENTICATION:
884 output_data("AUTHENTICATION");
887 output_data(" (empty suboption??\?)");
890 switch (pointer[1]) {
893 output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
895 if (AUTHTYPE_NAME_OK(pointer[2]))
896 output_data("%s ", AUTHTYPE_NAME(pointer[2]));
898 output_data("%d ", pointer[2]);
900 output_data("(partial suboption??\?)");
904 ((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
906 ((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
907 "MUTUAL" : "ONE-WAY");
911 auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
912 output_data("%s", buf);
918 output_data(" SEND ");
920 if (AUTHTYPE_NAME_OK(pointer[i]))
921 output_data("%s ", AUTHTYPE_NAME(pointer[i]));
923 output_data("%d ", pointer[i]);
925 output_data("(partial suboption??\?)");
928 output_data("%s|%s ",
929 ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
931 ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
932 "MUTUAL" : "ONE-WAY");
938 output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
942 for (i = 2; i < length; i++) {
943 output_data(" ?%d?", pointer[i]);
952 output_data("ENCRYPT");
954 output_data(" (empty suboption??\?)");
957 switch (pointer[1]) {
959 output_data(" START");
966 case ENCRYPT_REQSTART:
967 output_data(" REQUEST-START");
971 output_data(" REQUEST-END");
976 output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
979 output_data(" (partial suboption??\?)");
982 if (ENCTYPE_NAME_OK(pointer[2]))
983 output_data("%s ", ENCTYPE_NAME(pointer[2]));
985 output_data(" %d (unknown)", pointer[2]);
989 encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
990 output_data("%s", buf);
994 case ENCRYPT_SUPPORT:
996 output_data(" SUPPORT ");
998 if (ENCTYPE_NAME_OK(pointer[i]))
999 output_data("%s ", ENCTYPE_NAME(pointer[i]));
1001 output_data("%d ", pointer[i]);
1006 case ENCRYPT_ENC_KEYID:
1007 output_data(" ENC_KEYID");
1010 case ENCRYPT_DEC_KEYID:
1011 output_data(" DEC_KEYID");
1015 output_data(" %d (unknown)", pointer[1]);
1017 for (i = 2; i < length; i++) {
1018 output_data(" %d", pointer[i]);
1023 #endif /* ENCRYPTION */
1026 if (TELOPT_OK(pointer[0]))
1027 output_data("%s (unknown)", TELOPT(pointer[0]));
1029 output_data("%d (unknown)", pointer[i]);
1030 for (i = 1; i < length; i++) {
1031 output_data(" %d", pointer[i]);
1035 output_data("\r\n");
1039 * Dump a data buffer in hex and ascii to the output data stream.
1042 printdata(const char *tag, char *ptr, int cnt)
1048 /* flush net output buffer if no room for new data) */
1049 if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1053 /* add a line of output */
1054 output_data("%s: ", tag);
1055 for (i = 0; i < 20 && cnt; i++) {
1056 output_data("%02x", *ptr);
1057 if (isprint(*ptr)) {
1069 output_data(" %s\r\n", xbuf );
1072 #endif /* DIAGNOSTICS */