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
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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
36 static const char sccsid
[] = "@(#)utility.c 8.4 (Berkeley) 5/30/95";
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD: src/contrib/telnet/telnetd/utility.c,v 1.13 2003/05/04 02:54:49 obrien Exp $");
44 #include <sys/utsname.h>
51 #include <libtelnet/auth.h>
54 #include <libtelnet/encrypt.h>
58 * utility functions performing io related tasks
64 * A small subroutine to flush the network output buffer, get some data
65 * from the network, and pass it through the telnet state machine. We
66 * also flush the pty input buffer (by dropping its data) if it becomes
74 DIAG(TD_REPORT
, output_data("td: ttloop\r\n"));
75 if (nfrontp
- nbackp
> 0) {
78 ncc
= read(net
, netibuf
, sizeof netibuf
);
80 syslog(LOG_INFO
, "ttloop: read: %m");
82 } else if (ncc
== 0) {
83 syslog(LOG_INFO
, "ttloop: peer died: %m");
86 DIAG(TD_REPORT
, output_data("td: ttloop read %d chars\r\n", ncc
));
88 telrcv(); /* state machine */
90 pfrontp
= pbackp
= ptyobuf
;
96 * Check a descriptor to see if out of band data exists on it.
101 static struct timeval timeout
= { 0, 0 };
108 memset((char *)&timeout
, 0, sizeof timeout
);
109 value
= select(s
+1, (fd_set
*)0, (fd_set
*)0, &excepts
, &timeout
);
110 } while ((value
== -1) && (errno
== EINTR
));
113 fatalperror(pty
, "select");
115 if (FD_ISSET(s
, &excepts
)) {
127 if ((n
= pfrontp
- pbackp
) > 0) {
128 DIAG(TD_REPORT
| TD_PTYDATA
,
129 output_data("td: ptyflush %d chars\r\n", n
));
130 DIAG(TD_PTYDATA
, printdata("pd", pbackp
, n
));
131 n
= write(pty
, pbackp
, n
);
134 if (errno
== EWOULDBLOCK
|| errno
== EINTR
)
139 if (pbackp
== pfrontp
)
140 pbackp
= pfrontp
= ptyobuf
;
146 * Return the address of the next "item" in the TELNET data
147 * stream. This will be the address of the next character if
148 * the current address is a user data character, or it will
149 * be the address of the character following the TELNET command
150 * if the current address is a TELNET IAC ("I Am a Command")
154 nextitem(char *current
)
156 if ((*current
&0xff) != IAC
) {
159 switch (*(current
+1)&0xff) {
165 case SB
: /* loop forever looking for the SE */
167 char *look
= current
+2;
170 if ((*look
++&0xff) == IAC
) {
171 if ((*look
++&0xff) == SE
) {
180 } /* end of nextitem */
185 * We are about to do a TELNET SYNCH operation. Clear
186 * the path to the network.
188 * Things are a bit tricky since we may have sent the first
189 * byte or so of a previous TELNET command into the network.
190 * So, we have to scan the network buffer from the beginning
191 * until we are up to where we want to be.
193 * A side effect of what we do, just to keep things
194 * simple, is to clear the urgent data pointer. The principal
195 * caller should be setting the urgent data pointer AFTER calling
201 char *thisitem
, *next
;
203 #define wewant(p) ((nfrontp > p) && ((*p&0xff) == IAC) && \
204 ((*(p+1)&0xff) != EC) && ((*(p+1)&0xff) != EL))
207 thisitem
= nclearto
> netobuf
? nclearto
: netobuf
;
208 #else /* ENCRYPTION */
210 #endif /* ENCRYPTION */
212 while ((next
= nextitem(thisitem
)) <= nbackp
) {
216 /* Now, thisitem is first before/at boundary. */
219 good
= nclearto
> netobuf
? nclearto
: netobuf
;
220 #else /* ENCRYPTION */
221 good
= netobuf
; /* where the good bytes go */
222 #endif /* ENCRYPTION */
224 while (nfrontp
> thisitem
) {
225 if (wewant(thisitem
)) {
230 next
= nextitem(next
);
231 } while (wewant(next
) && (nfrontp
> next
));
232 length
= next
-thisitem
;
233 memmove(good
, thisitem
, length
);
237 thisitem
= nextitem(thisitem
);
242 nfrontp
= good
; /* next byte to be sent */
244 } /* end of netclear */
248 * Send as much data as possible to the network,
249 * handling requests for urgent data.
257 while ((n
= nfrontp
- nbackp
) > 0) {
259 /* XXX This causes output_data() to recurse and die */
261 n
+= output_data("td: netflush %d chars\r\n", n
);
265 if (encrypt_output
) {
266 char *s
= nclearto
? nclearto
: nbackp
;
267 if (nfrontp
- s
> 0) {
268 (*encrypt_output
)((unsigned char *)s
, nfrontp
-s
);
272 #endif /* ENCRYPTION */
274 * if no urgent data, or if the other side appears to be an
275 * old 4.2 client (and thus unable to survive TCP urgent data),
276 * write the entire buffer in non-OOB mode.
278 if ((neturg
== 0) || (not42
== 0)) {
279 n
= write(net
, nbackp
, n
); /* normal write */
283 * In 4.2 (and 4.3) systems, there is some question about
284 * what byte in a sendOOB operation is the "OOB" data.
285 * To make ourselves compatible, we only send ONE byte
286 * out of band, the one WE THINK should be OOB (though
287 * we really have more the TCP philosophy of urgent data
288 * rather than the Unix philosophy of OOB data).
291 n
= send(net
, nbackp
, n
-1, 0); /* send URGENT all by itself */
293 n
= send(net
, nbackp
, n
, MSG_OOB
); /* URGENT data */
297 if (errno
== EWOULDBLOCK
|| errno
== EINTR
)
304 if (nbackp
> nclearto
)
306 #endif /* ENCRYPTION */
307 if (nbackp
>= neturg
) {
310 if (nbackp
== nfrontp
) {
311 nbackp
= nfrontp
= netobuf
;
314 #endif /* ENCRYPTION */
318 } /* end of netflush */
322 * miscellaneous functions doing a variety of little jobs follow ...
327 fatal(int f
, const char *msg
)
331 (void) snprintf(buf
, sizeof(buf
), "telnetd: %s.\r\n", msg
);
333 if (encrypt_output
) {
335 * Better turn off encryption first....
341 #endif /* ENCRYPTION */
342 (void) write(f
, buf
, (int)strlen(buf
));
348 fatalperror(int f
, const char *msg
)
352 (void) snprintf(buf
, sizeof(buf
), "%s: %s", msg
, strerror(errno
));
359 edithost(char *pat
, char *host
)
361 char *res
= editedhost
;
382 if (res
== &editedhost
[sizeof editedhost
- 1]) {
389 (void) strncpy(res
, host
,
390 sizeof editedhost
- (res
- editedhost
) -1);
393 editedhost
[sizeof editedhost
- 1] = '\0';
396 static char *putlocation
;
399 putstr(const char *s
)
413 static char fmtstr
[] = { "%+" };
415 static char fmtstr
[] = { "%l:%M%P on %A, %d %B %Y" };
419 putf(char *cp
, char *where
)
425 static struct utsname kerninfo
;
427 if (!*kerninfo
.sysname
)
438 } else if (*cp
!= '%') {
446 /* names are like /dev/pts/2 -- we want pts/2 */
447 slash
= strchr(line
+1, '/');
449 slash
= strrchr(line
, '/');
451 if (slash
== (char *) 0)
463 setlocale(LC_TIME
, "");
466 (void)strftime(db
, sizeof(db
), fmtstr
, localtime(&t
));
472 putstr(kerninfo
.sysname
);
476 putstr(kerninfo
.machine
);
480 putstr(kerninfo
.release
);
484 putstr(kerninfo
.version
);
498 * Print telnet options and commands in plain text, if possible.
501 printoption(const char *fmt
, int option
)
503 if (TELOPT_OK(option
))
504 output_data("%s %s\r\n", fmt
, TELOPT(option
));
505 else if (TELCMD_OK(option
))
506 output_data("%s %s\r\n", fmt
, TELCMD(option
));
508 output_data("%s %d\r\n", fmt
, option
);
513 printsub(char direction
, unsigned char *pointer
, int length
)
517 if (!(diagnostic
& TD_OPTIONS
))
521 output_data("td: %s suboption ",
522 direction
== '<' ? "recv" : "send");
526 i
= pointer
[length
-2];
527 j
= pointer
[length
-1];
529 if (i
!= IAC
|| j
!= SE
) {
530 output_data("(terminated by ");
532 output_data("%s ", TELOPT(i
));
533 else if (TELCMD_OK(i
))
534 output_data("%s ", TELCMD(i
));
536 output_data("%d ", i
);
538 output_data("%s", TELOPT(j
));
539 else if (TELCMD_OK(j
))
540 output_data("%s", TELCMD(j
));
542 output_data("%d", j
);
543 output_data(", not IAC SE!) ");
549 output_data("(Empty suboption??\?)");
552 switch (pointer
[0]) {
554 output_data("TERMINAL-TYPE ");
555 switch (pointer
[1]) {
557 output_data("IS \"%.*s\"", length
-2, (char *)pointer
+2);
564 "- unknown qualifier %d (0x%x).",
565 pointer
[1], pointer
[1]);
569 output_data("TERMINAL-SPEED");
571 output_data(" (empty suboption??\?)");
574 switch (pointer
[1]) {
576 output_data(" IS %.*s", length
-2, (char *)pointer
+2);
580 output_data(" SEND");
582 output_data(" %d (unknown)", pointer
[1]);
583 for (i
= 2; i
< length
; i
++) {
584 output_data(" ?%d?", pointer
[i
]);
591 output_data("TOGGLE-FLOW-CONTROL");
593 output_data(" (empty suboption??\?)");
596 switch (pointer
[1]) {
598 output_data(" OFF"); break;
600 output_data(" ON"); break;
601 case LFLOW_RESTART_ANY
:
602 output_data(" RESTART-ANY"); break;
603 case LFLOW_RESTART_XON
:
604 output_data(" RESTART-XON"); break;
606 output_data(" %d (unknown)", pointer
[1]);
608 for (i
= 2; i
< length
; i
++) {
609 output_data(" ?%d?", pointer
[i
]);
616 output_data(" (empty suboption??\?)");
620 output_data(" ?%d?", pointer
[1]);
623 output_data(" %d %d (%d)",
624 pointer
[1], pointer
[2],
625 (int)((((unsigned int)pointer
[1])<<8)|((unsigned int)pointer
[2])));
627 output_data(" ?%d?", pointer
[3]);
630 output_data(" %d %d (%d)",
631 pointer
[3], pointer
[4],
632 (int)((((unsigned int)pointer
[3])<<8)|((unsigned int)pointer
[4])));
633 for (i
= 5; i
< length
; i
++) {
634 output_data(" ?%d?", pointer
[i
]);
638 case TELOPT_LINEMODE
:
639 output_data("LINEMODE ");
641 output_data(" (empty suboption??\?)");
644 switch (pointer
[1]) {
646 output_data("WILL ");
649 output_data("WONT ");
655 output_data("DONT ");
658 output_data("(no option??\?)");
661 switch (pointer
[2]) {
663 output_data("Forward Mask");
664 for (i
= 3; i
< length
; i
++) {
665 output_data(" %x", pointer
[i
]);
669 output_data("%d (unknown)", pointer
[2]);
670 for (i
= 3; i
< length
; i
++) {
671 output_data(" %d", pointer
[i
]);
679 for (i
= 2; i
< length
- 2; i
+= 3) {
680 if (SLC_NAME_OK(pointer
[i
+SLC_FUNC
]))
681 output_data(" %s", SLC_NAME(pointer
[i
+SLC_FUNC
]));
683 output_data(" %d", pointer
[i
+SLC_FUNC
]);
684 switch (pointer
[i
+SLC_FLAGS
]&SLC_LEVELBITS
) {
686 output_data(" NOSUPPORT"); break;
688 output_data(" CANTCHANGE"); break;
690 output_data(" VARIABLE"); break;
692 output_data(" DEFAULT"); break;
694 output_data("%s%s%s",
695 pointer
[i
+SLC_FLAGS
]&SLC_ACK
? "|ACK" : "",
696 pointer
[i
+SLC_FLAGS
]&SLC_FLUSHIN
? "|FLUSHIN" : "",
697 pointer
[i
+SLC_FLAGS
]&SLC_FLUSHOUT
? "|FLUSHOUT" : "");
698 if (pointer
[i
+SLC_FLAGS
]& ~(SLC_ACK
|SLC_FLUSHIN
|
699 SLC_FLUSHOUT
| SLC_LEVELBITS
)) {
700 output_data("(0x%x)", pointer
[i
+SLC_FLAGS
]);
702 output_data(" %d;", pointer
[i
+SLC_VALUE
]);
703 if ((pointer
[i
+SLC_VALUE
] == IAC
) &&
704 (pointer
[i
+SLC_VALUE
+1] == IAC
))
707 for (; i
< length
; i
++) {
708 output_data(" ?%d?", pointer
[i
]);
713 output_data("MODE ");
715 output_data("(no mode??\?)");
720 sprintf(tbuf
, "%s%s%s%s%s",
721 pointer
[2]&MODE_EDIT
? "|EDIT" : "",
722 pointer
[2]&MODE_TRAPSIG
? "|TRAPSIG" : "",
723 pointer
[2]&MODE_SOFT_TAB
? "|SOFT_TAB" : "",
724 pointer
[2]&MODE_LIT_ECHO
? "|LIT_ECHO" : "",
725 pointer
[2]&MODE_ACK
? "|ACK" : "");
726 output_data("%s", tbuf
[1] ? &tbuf
[1] : "0");
728 if (pointer
[2]&~(MODE_EDIT
|MODE_TRAPSIG
|MODE_ACK
)) {
729 output_data(" (0x%x)", pointer
[2]);
731 for (i
= 3; i
< length
; i
++) {
732 output_data(" ?0x%x?", pointer
[i
]);
736 output_data("%d (unknown)", pointer
[1]);
737 for (i
= 2; i
< length
; i
++) {
738 output_data(" %d", pointer
[i
]);
743 case TELOPT_STATUS
: {
747 output_data("STATUS");
749 switch (pointer
[1]) {
751 if (pointer
[1] == TELQUAL_SEND
)
752 output_data(" SEND");
754 output_data(" %d (unknown)", pointer
[1]);
755 for (i
= 2; i
< length
; i
++) {
756 output_data(" ?%d?", pointer
[i
]);
760 output_data(" IS\r\n");
762 for (i
= 2; i
< length
; i
++) {
764 case DO
: cp
= "DO"; goto common2
;
765 case DONT
: cp
= "DONT"; goto common2
;
766 case WILL
: cp
= "WILL"; goto common2
;
767 case WONT
: cp
= "WONT"; goto common2
;
770 if (TELOPT_OK(pointer
[i
]))
771 output_data(" %s %s", cp
, TELOPT(pointer
[i
]));
773 output_data(" %s %d", cp
, pointer
[i
]);
783 if (pointer
[j
] == SE
) {
786 if (pointer
[j
+1] == SE
)
791 pointer
[k
++] = pointer
[j
++];
793 printsub(0, &pointer
[i
], k
- i
);
805 output_data(" %d", pointer
[i
]);
814 case TELOPT_XDISPLOC
:
815 output_data("X-DISPLAY-LOCATION ");
816 switch (pointer
[1]) {
818 output_data("IS \"%.*s\"", length
-2, (char *)pointer
+2);
824 output_data("- unknown qualifier %d (0x%x).",
825 pointer
[1], pointer
[1]);
829 case TELOPT_NEW_ENVIRON
:
830 output_data("NEW-ENVIRON ");
832 case TELOPT_OLD_ENVIRON
:
833 output_data("OLD-ENVIRON");
835 switch (pointer
[1]) {
840 output_data("SEND ");
843 output_data("INFO ");
847 for (i
= 2; i
< length
; i
++ ) {
848 switch (pointer
[i
]) {
850 output_data("\" VAR " + noquote
);
855 output_data("\" VALUE " + noquote
);
860 output_data("\" ESC " + noquote
);
865 output_data("\" USERVAR " + noquote
);
870 if (isprint(pointer
[i
]) && pointer
[i
] != '"') {
875 output_data("%c", pointer
[i
]);
877 output_data("\" %03o " + noquote
,
891 #ifdef AUTHENTICATION
892 case TELOPT_AUTHENTICATION
:
893 output_data("AUTHENTICATION");
896 output_data(" (empty suboption??\?)");
899 switch (pointer
[1]) {
902 output_data(" %s ", (pointer
[1] == TELQUAL_IS
) ?
904 if (AUTHTYPE_NAME_OK(pointer
[2]))
905 output_data("%s ", AUTHTYPE_NAME(pointer
[2]));
907 output_data("%d ", pointer
[2]);
909 output_data("(partial suboption??\?)");
913 ((pointer
[3] & AUTH_WHO_MASK
) == AUTH_WHO_CLIENT
) ?
915 ((pointer
[3] & AUTH_HOW_MASK
) == AUTH_HOW_MUTUAL
) ?
916 "MUTUAL" : "ONE-WAY");
920 auth_printsub(&pointer
[1], length
- 1, buf
, sizeof(buf
));
921 output_data("%s", buf
);
927 output_data(" SEND ");
929 if (AUTHTYPE_NAME_OK(pointer
[i
]))
930 output_data("%s ", AUTHTYPE_NAME(pointer
[i
]));
932 output_data("%d ", pointer
[i
]);
934 output_data("(partial suboption??\?)");
937 output_data("%s|%s ",
938 ((pointer
[i
] & AUTH_WHO_MASK
) == AUTH_WHO_CLIENT
) ?
940 ((pointer
[i
] & AUTH_HOW_MASK
) == AUTH_HOW_MUTUAL
) ?
941 "MUTUAL" : "ONE-WAY");
947 output_data(" NAME \"%.*s\"", length
- 2, pointer
+ 2);
951 for (i
= 2; i
< length
; i
++) {
952 output_data(" ?%d?", pointer
[i
]);
961 output_data("ENCRYPT");
963 output_data(" (empty suboption??\?)");
966 switch (pointer
[1]) {
968 output_data(" START");
975 case ENCRYPT_REQSTART
:
976 output_data(" REQUEST-START");
980 output_data(" REQUEST-END");
985 output_data(" %s ", (pointer
[1] == ENCRYPT_IS
) ?
988 output_data(" (partial suboption??\?)");
991 if (ENCTYPE_NAME_OK(pointer
[2]))
992 output_data("%s ", ENCTYPE_NAME(pointer
[2]));
994 output_data(" %d (unknown)", pointer
[2]);
998 encrypt_printsub(&pointer
[1], length
- 1, buf
, sizeof(buf
));
999 output_data("%s", buf
);
1003 case ENCRYPT_SUPPORT
:
1005 output_data(" SUPPORT ");
1006 while (i
< length
) {
1007 if (ENCTYPE_NAME_OK(pointer
[i
]))
1008 output_data("%s ", ENCTYPE_NAME(pointer
[i
]));
1010 output_data("%d ", pointer
[i
]);
1015 case ENCRYPT_ENC_KEYID
:
1016 output_data(" ENC_KEYID");
1019 case ENCRYPT_DEC_KEYID
:
1020 output_data(" DEC_KEYID");
1024 output_data(" %d (unknown)", pointer
[1]);
1026 for (i
= 2; i
< length
; i
++) {
1027 output_data(" %d", pointer
[i
]);
1032 #endif /* ENCRYPTION */
1035 if (TELOPT_OK(pointer
[0]))
1036 output_data("%s (unknown)", TELOPT(pointer
[0]));
1038 output_data("%d (unknown)", pointer
[i
]);
1039 for (i
= 1; i
< length
; i
++) {
1040 output_data(" %d", pointer
[i
]);
1044 output_data("\r\n");
1048 * Dump a data buffer in hex and ascii to the output data stream.
1051 printdata(const char *tag
, char *ptr
, int cnt
)
1057 /* flush net output buffer if no room for new data) */
1058 if ((&netobuf
[BUFSIZ
] - nfrontp
) < 80) {
1062 /* add a line of output */
1063 output_data("%s: ", tag
);
1064 for (i
= 0; i
< 20 && cnt
; i
++) {
1065 output_data("%02x", *ptr
);
1066 if (isprint(*ptr
)) {
1078 output_data(" %s\r\n", xbuf
);
1081 #endif /* DIAGNOSTICS */