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 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * @(#)utility.c 8.4 (Berkeley) 5/30/95
34 * $FreeBSD: src/crypto/telnet/telnetd/utility.c,v 1.5.2.4 2002/04/13 10:59:09 markm Exp $
35 * $DragonFly: src/crypto/telnet/telnetd/utility.c,v 1.2 2003/06/17 04:24:37 dillon Exp $
40 #include <sys/utsname.h>
47 #include <libtelnet/auth.h>
50 #include <libtelnet/encrypt.h>
54 * utility functions performing io related tasks
60 * A small subroutine to flush the network output buffer, get some data
61 * from the network, and pass it through the telnet state machine. We
62 * also flush the pty input buffer (by dropping its data) if it becomes
70 DIAG(TD_REPORT, output_data("td: ttloop\r\n"));
71 if (nfrontp - nbackp > 0) {
74 ncc = read(net, netibuf, sizeof netibuf);
76 syslog(LOG_INFO, "ttloop: read: %m");
78 } else if (ncc == 0) {
79 syslog(LOG_INFO, "ttloop: peer died: %m");
82 DIAG(TD_REPORT, output_data("td: ttloop read %d chars\r\n", ncc));
84 telrcv(); /* state machine */
86 pfrontp = pbackp = ptyobuf;
92 * Check a descriptor to see if out of band data exists on it.
97 static struct timeval timeout = { 0, 0 };
104 memset((char *)&timeout, 0, sizeof timeout);
105 value = select(s+1, NULL, NULL, &excepts, &timeout);
106 } while ((value == -1) && (errno == EINTR));
109 fatalperror(pty, "select");
111 if (FD_ISSET(s, &excepts)) {
123 if ((n = pfrontp - pbackp) > 0) {
124 DIAG(TD_REPORT | TD_PTYDATA,
125 output_data("td: ptyflush %d chars\r\n", n));
126 DIAG(TD_PTYDATA, printdata("pd", pbackp, n));
127 n = write(pty, pbackp, n);
130 if (errno == EWOULDBLOCK || errno == EINTR)
135 if (pbackp == pfrontp)
136 pbackp = pfrontp = ptyobuf;
142 * Return the address of the next "item" in the TELNET data
143 * stream. This will be the address of the next character if
144 * the current address is a user data character, or it will
145 * be the address of the character following the TELNET command
146 * if the current address is a TELNET IAC ("I Am a Command")
150 nextitem(char *current)
152 if ((*current&0xff) != IAC) {
155 switch (*(current+1)&0xff) {
161 case SB: /* loop forever looking for the SE */
163 char *look = current+2;
166 if ((*look++&0xff) == IAC) {
167 if ((*look++&0xff) == SE) {
176 } /* end of nextitem */
181 * We are about to do a TELNET SYNCH operation. Clear
182 * the path to the network.
184 * Things are a bit tricky since we may have sent the first
185 * byte or so of a previous TELNET command into the network.
186 * So, we have to scan the network buffer from the beginning
187 * until we are up to where we want to be.
189 * A side effect of what we do, just to keep things
190 * simple, is to clear the urgent data pointer. The principal
191 * caller should be setting the urgent data pointer AFTER calling
197 char *thisitem, *next;
199 #define wewant(p) ((nfrontp > p) && ((*p&0xff) == IAC) && \
200 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
203 thisitem = nclearto > netobuf ? nclearto : netobuf;
204 #else /* ENCRYPTION */
206 #endif /* ENCRYPTION */
208 while ((next = nextitem(thisitem)) <= nbackp) {
212 /* Now, thisitem is first before/at boundary. */
215 good = nclearto > netobuf ? nclearto : netobuf;
216 #else /* ENCRYPTION */
217 good = netobuf; /* where the good bytes go */
218 #endif /* ENCRYPTION */
220 while (nfrontp > thisitem) {
221 if (wewant(thisitem)) {
226 next = nextitem(next);
227 } while (wewant(next) && (nfrontp > next));
228 length = next-thisitem;
229 memmove(good, thisitem, length);
233 thisitem = nextitem(thisitem);
238 nfrontp = good; /* next byte to be sent */
240 } /* end of netclear */
244 * Send as much data as possible to the network,
245 * handling requests for urgent data.
253 while ((n = nfrontp - nbackp) > 0) {
255 /* XXX This causes output_data() to recurse and die */
257 n += output_data("td: netflush %d chars\r\n", n);
261 if (encrypt_output) {
262 char *s = nclearto ? nclearto : nbackp;
263 if (nfrontp - s > 0) {
264 (*encrypt_output)((unsigned char *)s, nfrontp-s);
268 #endif /* ENCRYPTION */
270 * if no urgent data, or if the other side appears to be an
271 * old 4.2 client (and thus unable to survive TCP urgent data),
272 * write the entire buffer in non-OOB mode.
274 if ((neturg == 0) || (not42 == 0)) {
275 n = write(net, nbackp, n); /* normal write */
279 * In 4.2 (and 4.3) systems, there is some question about
280 * what byte in a sendOOB operation is the "OOB" data.
281 * To make ourselves compatible, we only send ONE byte
282 * out of band, the one WE THINK should be OOB (though
283 * we really have more the TCP philosophy of urgent data
284 * rather than the Unix philosophy of OOB data).
287 n = send(net, nbackp, n-1, 0); /* send URGENT all by itself */
289 n = send(net, nbackp, n, MSG_OOB); /* URGENT data */
293 if (errno == EWOULDBLOCK || errno == EINTR)
300 if (nbackp > nclearto)
302 #endif /* ENCRYPTION */
303 if (nbackp >= neturg) {
306 if (nbackp == nfrontp) {
307 nbackp = nfrontp = netobuf;
310 #endif /* ENCRYPTION */
314 } /* end of netflush */
318 * miscellaneous functions doing a variety of little jobs follow ...
323 fatal(int f, const char *msg)
327 (void) snprintf(buf, sizeof(buf), "telnetd: %s.\r\n", msg);
329 if (encrypt_output) {
331 * Better turn off encryption first....
337 #endif /* ENCRYPTION */
338 (void) write(f, buf, (int)strlen(buf));
344 fatalperror(int f, const char *msg)
348 (void) snprintf(buf, sizeof(buf), "%s: %s", msg, strerror(errno));
355 edithost(char *pat, char *host)
357 char *res = editedhost;
378 if (res == &editedhost[sizeof editedhost - 1]) {
385 (void) strncpy(res, host,
386 sizeof editedhost - (res - editedhost) -1);
389 editedhost[sizeof editedhost - 1] = '\0';
392 static char *putlocation;
395 putstr(const char *s)
409 static char fmtstr[] = { "%+" };
411 static char fmtstr[] = { "%l:%M%P on %A, %d %B %Y" };
415 putf(char *cp, char *where)
421 static struct utsname kerninfo;
423 if (!*kerninfo.sysname)
434 } else if (*cp != '%') {
442 /* names are like /dev/pts/2 -- we want pts/2 */
443 slash = strchr(line+1, '/');
445 slash = strrchr(line, '/');
447 if (slash == (char *) 0)
459 setlocale(LC_TIME, "");
462 (void)strftime(db, sizeof(db), fmtstr, localtime(&t));
468 putstr(kerninfo.sysname);
472 putstr(kerninfo.machine);
476 putstr(kerninfo.release);
480 putstr(kerninfo.version);
494 * Print telnet options and commands in plain text, if possible.
497 printoption(const char *fmt, int option)
499 if (TELOPT_OK(option))
500 output_data("%s %s\r\n", fmt, TELOPT(option));
501 else if (TELCMD_OK(option))
502 output_data("%s %s\r\n", fmt, TELCMD(option));
504 output_data("%s %d\r\n", fmt, option);
509 printsub(char direction, unsigned char *pointer, int length)
513 if (!(diagnostic & TD_OPTIONS))
517 output_data("td: %s suboption ",
518 direction == '<' ? "recv" : "send");
522 i = pointer[length-2];
523 j = pointer[length-1];
525 if (i != IAC || j != SE) {
526 output_data("(terminated by ");
528 output_data("%s ", TELOPT(i));
529 else if (TELCMD_OK(i))
530 output_data("%s ", TELCMD(i));
532 output_data("%d ", i);
534 output_data("%s", TELOPT(j));
535 else if (TELCMD_OK(j))
536 output_data("%s", TELCMD(j));
538 output_data("%d", j);
539 output_data(", not IAC SE!) ");
545 output_data("(Empty suboption??\?)");
548 switch (pointer[0]) {
550 output_data("TERMINAL-TYPE ");
551 switch (pointer[1]) {
553 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
560 "- unknown qualifier %d (0x%x).",
561 pointer[1], pointer[1]);
565 output_data("TERMINAL-SPEED");
567 output_data(" (empty suboption??\?)");
570 switch (pointer[1]) {
572 output_data(" IS %.*s", length-2, (char *)pointer+2);
576 output_data(" SEND");
578 output_data(" %d (unknown)", pointer[1]);
579 for (i = 2; i < length; i++) {
580 output_data(" ?%d?", pointer[i]);
587 output_data("TOGGLE-FLOW-CONTROL");
589 output_data(" (empty suboption??\?)");
592 switch (pointer[1]) {
594 output_data(" OFF"); break;
596 output_data(" ON"); break;
597 case LFLOW_RESTART_ANY:
598 output_data(" RESTART-ANY"); break;
599 case LFLOW_RESTART_XON:
600 output_data(" RESTART-XON"); break;
602 output_data(" %d (unknown)", pointer[1]);
604 for (i = 2; i < length; i++) {
605 output_data(" ?%d?", pointer[i]);
612 output_data(" (empty suboption??\?)");
616 output_data(" ?%d?", pointer[1]);
619 output_data(" %d %d (%d)",
620 pointer[1], pointer[2],
621 (int)((((unsigned int)pointer[1])<<8)|((unsigned int)pointer[2])));
623 output_data(" ?%d?", pointer[3]);
626 output_data(" %d %d (%d)",
627 pointer[3], pointer[4],
628 (int)((((unsigned int)pointer[3])<<8)|((unsigned int)pointer[4])));
629 for (i = 5; i < length; i++) {
630 output_data(" ?%d?", pointer[i]);
634 case TELOPT_LINEMODE:
635 output_data("LINEMODE ");
637 output_data(" (empty suboption??\?)");
640 switch (pointer[1]) {
642 output_data("WILL ");
645 output_data("WONT ");
651 output_data("DONT ");
654 output_data("(no option??\?)");
657 switch (pointer[2]) {
659 output_data("Forward Mask");
660 for (i = 3; i < length; i++) {
661 output_data(" %x", pointer[i]);
665 output_data("%d (unknown)", pointer[2]);
666 for (i = 3; i < length; i++) {
667 output_data(" %d", pointer[i]);
675 for (i = 2; i < length - 2; i += 3) {
676 if (SLC_NAME_OK(pointer[i+SLC_FUNC]))
677 output_data(" %s", SLC_NAME(pointer[i+SLC_FUNC]));
679 output_data(" %d", pointer[i+SLC_FUNC]);
680 switch (pointer[i+SLC_FLAGS]&SLC_LEVELBITS) {
682 output_data(" NOSUPPORT"); break;
684 output_data(" CANTCHANGE"); break;
686 output_data(" VARIABLE"); break;
688 output_data(" DEFAULT"); break;
690 output_data("%s%s%s",
691 pointer[i+SLC_FLAGS]&SLC_ACK ? "|ACK" : "",
692 pointer[i+SLC_FLAGS]&SLC_FLUSHIN ? "|FLUSHIN" : "",
693 pointer[i+SLC_FLAGS]&SLC_FLUSHOUT ? "|FLUSHOUT" : "");
694 if (pointer[i+SLC_FLAGS]& ~(SLC_ACK|SLC_FLUSHIN|
695 SLC_FLUSHOUT| SLC_LEVELBITS)) {
696 output_data("(0x%x)", pointer[i+SLC_FLAGS]);
698 output_data(" %d;", pointer[i+SLC_VALUE]);
699 if ((pointer[i+SLC_VALUE] == IAC) &&
700 (pointer[i+SLC_VALUE+1] == IAC))
703 for (; i < length; i++) {
704 output_data(" ?%d?", pointer[i]);
709 output_data("MODE ");
711 output_data("(no mode??\?)");
716 sprintf(tbuf, "%s%s%s%s%s",
717 pointer[2]&MODE_EDIT ? "|EDIT" : "",
718 pointer[2]&MODE_TRAPSIG ? "|TRAPSIG" : "",
719 pointer[2]&MODE_SOFT_TAB ? "|SOFT_TAB" : "",
720 pointer[2]&MODE_LIT_ECHO ? "|LIT_ECHO" : "",
721 pointer[2]&MODE_ACK ? "|ACK" : "");
722 output_data("%s", tbuf[1] ? &tbuf[1] : "0");
724 if (pointer[2]&~(MODE_EDIT|MODE_TRAPSIG|MODE_ACK)) {
725 output_data(" (0x%x)", pointer[2]);
727 for (i = 3; i < length; i++) {
728 output_data(" ?0x%x?", pointer[i]);
732 output_data("%d (unknown)", pointer[1]);
733 for (i = 2; i < length; i++) {
734 output_data(" %d", pointer[i]);
739 case TELOPT_STATUS: {
743 output_data("STATUS");
745 switch (pointer[1]) {
747 if (pointer[1] == TELQUAL_SEND)
748 output_data(" SEND");
750 output_data(" %d (unknown)", pointer[1]);
751 for (i = 2; i < length; i++) {
752 output_data(" ?%d?", pointer[i]);
756 output_data(" IS\r\n");
758 for (i = 2; i < length; i++) {
760 case DO: cp = "DO"; goto common2;
761 case DONT: cp = "DONT"; goto common2;
762 case WILL: cp = "WILL"; goto common2;
763 case WONT: cp = "WONT"; goto common2;
766 if (TELOPT_OK(pointer[i]))
767 output_data(" %s %s", cp, TELOPT(pointer[i]));
769 output_data(" %s %d", cp, pointer[i]);
779 if (pointer[j] == SE) {
782 if (pointer[j+1] == SE)
787 pointer[k++] = pointer[j++];
789 printsub(0, &pointer[i], k - i);
801 output_data(" %d", pointer[i]);
810 case TELOPT_XDISPLOC:
811 output_data("X-DISPLAY-LOCATION ");
812 switch (pointer[1]) {
814 output_data("IS \"%.*s\"", length-2, (char *)pointer+2);
820 output_data("- unknown qualifier %d (0x%x).",
821 pointer[1], pointer[1]);
825 case TELOPT_NEW_ENVIRON:
826 output_data("NEW-ENVIRON ");
828 case TELOPT_OLD_ENVIRON:
829 output_data("OLD-ENVIRON");
831 switch (pointer[1]) {
836 output_data("SEND ");
839 output_data("INFO ");
843 for (i = 2; i < length; i++ ) {
844 switch (pointer[i]) {
846 output_data("\" VAR " + noquote);
851 output_data("\" VALUE " + noquote);
856 output_data("\" ESC " + noquote);
861 output_data("\" USERVAR " + noquote);
866 if (isprint(pointer[i]) && pointer[i] != '"') {
871 output_data("%c", pointer[i]);
873 output_data("\" %03o " + noquote,
887 #ifdef AUTHENTICATION
888 case TELOPT_AUTHENTICATION:
889 output_data("AUTHENTICATION");
892 output_data(" (empty suboption??\?)");
895 switch (pointer[1]) {
898 output_data(" %s ", (pointer[1] == TELQUAL_IS) ?
900 if (AUTHTYPE_NAME_OK(pointer[2]))
901 output_data("%s ", AUTHTYPE_NAME(pointer[2]));
903 output_data("%d ", pointer[2]);
905 output_data("(partial suboption??\?)");
909 ((pointer[3] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
911 ((pointer[3] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
912 "MUTUAL" : "ONE-WAY");
916 auth_printsub(&pointer[1], length - 1, buf, sizeof(buf));
917 output_data("%s", buf);
923 output_data(" SEND ");
925 if (AUTHTYPE_NAME_OK(pointer[i]))
926 output_data("%s ", AUTHTYPE_NAME(pointer[i]));
928 output_data("%d ", pointer[i]);
930 output_data("(partial suboption??\?)");
933 output_data("%s|%s ",
934 ((pointer[i] & AUTH_WHO_MASK) == AUTH_WHO_CLIENT) ?
936 ((pointer[i] & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) ?
937 "MUTUAL" : "ONE-WAY");
943 output_data(" NAME \"%.*s\"", length - 2, pointer + 2);
947 for (i = 2; i < length; i++) {
948 output_data(" ?%d?", pointer[i]);
957 output_data("ENCRYPT");
959 output_data(" (empty suboption??\?)");
962 switch (pointer[1]) {
964 output_data(" START");
971 case ENCRYPT_REQSTART:
972 output_data(" REQUEST-START");
976 output_data(" REQUEST-END");
981 output_data(" %s ", (pointer[1] == ENCRYPT_IS) ?
984 output_data(" (partial suboption??\?)");
987 if (ENCTYPE_NAME_OK(pointer[2]))
988 output_data("%s ", ENCTYPE_NAME(pointer[2]));
990 output_data(" %d (unknown)", pointer[2]);
994 encrypt_printsub(&pointer[1], length - 1, buf, sizeof(buf));
995 output_data("%s", buf);
999 case ENCRYPT_SUPPORT:
1001 output_data(" SUPPORT ");
1002 while (i < length) {
1003 if (ENCTYPE_NAME_OK(pointer[i]))
1004 output_data("%s ", ENCTYPE_NAME(pointer[i]));
1006 output_data("%d ", pointer[i]);
1011 case ENCRYPT_ENC_KEYID:
1012 output_data(" ENC_KEYID");
1015 case ENCRYPT_DEC_KEYID:
1016 output_data(" DEC_KEYID");
1020 output_data(" %d (unknown)", pointer[1]);
1022 for (i = 2; i < length; i++) {
1023 output_data(" %d", pointer[i]);
1028 #endif /* ENCRYPTION */
1031 if (TELOPT_OK(pointer[0]))
1032 output_data("%s (unknown)", TELOPT(pointer[0]));
1034 output_data("%d (unknown)", pointer[i]);
1035 for (i = 1; i < length; i++) {
1036 output_data(" %d", pointer[i]);
1040 output_data("\r\n");
1044 * Dump a data buffer in hex and ascii to the output data stream.
1047 printdata(const char *tag, char *ptr, int cnt)
1053 /* flush net output buffer if no room for new data) */
1054 if ((&netobuf[BUFSIZ] - nfrontp) < 80) {
1058 /* add a line of output */
1059 output_data("%s: ", tag);
1060 for (i = 0; i < 20 && cnt; i++) {
1061 output_data("%02x", *ptr);
1062 if (isprint(*ptr)) {
1074 output_data(" %s\r\n", xbuf );
1077 #endif /* DIAGNOSTICS */