← Commit list

9f2f808b0

Denis Vlasenko

2008-11-11

FAILED Duration: 34s

Subject

telnetd: correctly output 0xff char. ~100 bytes. telnet: fix some atrocious names and style. no code changes

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

networking/telnet.c +117 -115 networking/telnetd.c +51 -7

networking/telnet.c+117 -115

@@ -93,7 +93,7 @@ static void will_charmode(void);
	static void telopt(byte c);
	static int subneg(byte c);

-	static void iacflush(void)
+	static void iac_flush(void)
	{
	write(netfd, G.iacbuf, G.iaclen);
	G.iaclen = 0;
@@ -108,11 +108,11 @@ static void doexit(int ev)
	exit(ev);
	}

-	static void conescape(void)
+	static void con_escape(void)
	{
	char b;

-	if (bb_got_signal) /* came from line mode... go raw */
+	if (bb_got_signal) /* came from line mode... go raw */
	rawmode();

	write_str(1, "\r\nConsole escape. Commands are:\r\n\n"
@@ -128,13 +128,13 @@ static void conescape(void)
	case 'l':
	if (!bb_got_signal) {
	do_linemode();
-	goto rrturn;
+	goto ret;
	}
	break;
	case 'c':
	if (bb_got_signal) {
	will_charmode();
-	goto rrturn;
+	goto ret;
	}
	break;
	case 'z':
@@ -150,13 +150,12 @@ static void conescape(void)

	if (bb_got_signal)
	cookmode();
-
-	rrturn:
+	ret:
	bb_got_signal = 0;

	}

-	static void handlenetoutput(int len)
+	static void handle_net_output(int len)
	{
	/* here we could do smart tricks how to handle 0xFF:s in output
	* stream like writing twice every sequence of FF:s (thus doing
@@ -169,19 +168,19 @@ static void handlenetoutput(int len)
	* first - I cannot use programs like sz/rz
	* second - the 0x0D is sent as one character and if the next
	* char is 0x0A then it's eaten by a server side.
-	* third - whay doy you have to make 'many write()s'?
+	* third - why do you have to make 'many write()s'?
	* I don't understand.
-	* So I implemented it. It's realy useful for me. I hope that
-	* others people will find it interesting too.
+	* So I implemented it. It's really useful for me. I hope that
+	* other people will find it interesting too.
	*/

	int i, j;
-	byte * p = (byte*)G.buf;
+	byte p = (byte)G.buf;
	byte outbuf[4*DATABUFSIZE];

	for (i = len, j = 0; i > 0; i--, p++) {
	if (*p == 0x1d) {
-	conescape();
+	con_escape();
	return;
	}
	outbuf[j++] = *p;
@@ -194,7 +193,7 @@ static void handlenetoutput(int len)
	write(netfd, outbuf, j);
	}

-	static void handlenetinput(int len)
+	static void handle_net_input(int len)
	{
	int i;
	int cstart = 0;
@@ -207,51 +206,54 @@ static void handlenetinput(int len)
	cstart = i;
	G.telstate = TS_IAC;
	}
-	} else
-	switch (G.telstate) {
-	case TS_0:
-	if (c == IAC)
-	G.telstate = TS_IAC;
-	else
-	G.buf[cstart++] = c;
-	break;
+	continue;
+	}
+	switch (G.telstate) {
+	case TS_0:
+	if (c == IAC)
+	G.telstate = TS_IAC;
+	else
+	G.buf[cstart++] = c;
+	break;

-	case TS_IAC:
-	if (c == IAC) { /* IAC IAC -> 0xFF */
-	G.buf[cstart++] = c;
-	G.telstate = TS_0;
-	break;
-	}
-	/* else */
-	switch (c) {
-	case SB:
-	G.telstate = TS_SUB1;
-	break;
-	case DO:
-	case DONT:
-	case WILL:
-	case WONT:
-	G.telwish = c;
-	G.telstate = TS_OPT;
-	break;
-	default:
-	G.telstate = TS_0; /* DATA MARK must be added later */
-	}
-	break;
-	case TS_OPT: /* WILL, WONT, DO, DONT */
-	telopt(c);
+	case TS_IAC:
+	if (c == IAC) { /* IAC IAC -> 0xFF */
+	G.buf[cstart++] = c;
	G.telstate = TS_0;
	break;
-	case TS_SUB1: /* Subnegotiation */
-	case TS_SUB2: /* Subnegotiation */
-	if (subneg(c))
-	G.telstate = TS_0;
+	}
+	/* else */
+	switch (c) {
+	case SB:
+	G.telstate = TS_SUB1;
+	break;
+	case DO:
+	case DONT:
+	case WILL:
+	case WONT:
+	G.telwish = c;
+	G.telstate = TS_OPT;
	break;
+	default:
+	G.telstate = TS_0; /* DATA MARK must be added later */
	}
+	break;
+	case TS_OPT: /* WILL, WONT, DO, DONT */
+	telopt(c);
+	G.telstate = TS_0;
+	break;
+	case TS_SUB1: /* Subnegotiation */
+	case TS_SUB2: /* Subnegotiation */
+	if (subneg(c))
+	G.telstate = TS_0;
+	break;
+	}
	}
	if (G.telstate) {
-	if (G.iaclen) iacflush();
-	if (G.telstate == TS_0) G.telstate = 0;
+	if (G.iaclen)
+	iac_flush();
+	if (G.telstate == TS_0)
+	G.telstate = 0;
	len = cstart;
	}

@@ -259,87 +261,87 @@ static void handlenetinput(int len)
	write(STDOUT_FILENO, G.buf, len);
	}

-	static void putiac(int c)
+	static void put_iac(int c)
	{
	G.iacbuf[G.iaclen++] = c;
	}

-	static void putiac2(byte wwdd, byte c)
+	static void put_iac2(byte wwdd, byte c)
	{
	if (G.iaclen + 3 > IACBUFSIZE)
-	iacflush();
+	iac_flush();

-	putiac(IAC);
-	putiac(wwdd);
-	putiac(c);
+	put_iac(IAC);
+	put_iac(wwdd);
+	put_iac(c);
	}

	#if ENABLE_FEATURE_TELNET_TTYPE
-	static void putiac_subopt(byte c, char *str)
+	static void put_iac_subopt(byte c, char *str)
	{
-	int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )
+	int len = strlen(str) + 6; // ( 2 + 1 + 1 + strlen + 2 )

	if (G.iaclen + len > IACBUFSIZE)
-	iacflush();
+	iac_flush();

-	putiac(IAC);
-	putiac(SB);
-	putiac(c);
-	putiac(0);
+	put_iac(IAC);
+	put_iac(SB);
+	put_iac(c);
+	put_iac(0);

	while (*str)
-	putiac(*str++);
+	put_iac(*str++);

-	putiac(IAC);
-	putiac(SE);
+	put_iac(IAC);
+	put_iac(SE);
	}
	#endif

	#if ENABLE_FEATURE_TELNET_AUTOLOGIN
-	static void putiac_subopt_autologin(void)
+	static void put_iac_subopt_autologin(void)
	{
	int len = strlen(G.autologin) + 6; // (2 + 1 + 1 + strlen + 2)
	const char *user = "USER";

	if (G.iaclen + len > IACBUFSIZE)
-	iacflush();
+	iac_flush();

-	putiac(IAC);
-	putiac(SB);
-	putiac(TELOPT_NEW_ENVIRON);
-	putiac(TELQUAL_IS);
-	putiac(NEW_ENV_VAR);
+	put_iac(IAC);
+	put_iac(SB);
+	put_iac(TELOPT_NEW_ENVIRON);
+	put_iac(TELQUAL_IS);
+	put_iac(NEW_ENV_VAR);

	while (*user)
-	putiac(*user++);
+	put_iac(*user++);

-	putiac(NEW_ENV_VALUE);
+	put_iac(NEW_ENV_VALUE);

	while (*G.autologin)
-	putiac(*G.autologin++);
+	put_iac(*G.autologin++);

-	putiac(IAC);
-	putiac(SE);
+	put_iac(IAC);
+	put_iac(SE);
	}
	#endif

	#if ENABLE_FEATURE_AUTOWIDTH
-	static void putiac_naws(byte c, int x, int y)
+	static void put_iac_naws(byte c, int x, int y)
	{
	if (G.iaclen + 9 > IACBUFSIZE)
-	iacflush();
+	iac_flush();

-	putiac(IAC);
-	putiac(SB);
-	putiac(c);
+	put_iac(IAC);
+	put_iac(SB);
+	put_iac(c);

-	putiac((x >> 8) & 0xff);
-	putiac(x & 0xff);
-	putiac((y >> 8) & 0xff);
-	putiac(y & 0xff);
+	put_iac((x >> 8) & 0xff);
+	put_iac(x & 0xff);
+	put_iac((y >> 8) & 0xff);
+	put_iac(y & 0xff);

-	putiac(IAC);
-	putiac(SE);
+	put_iac(IAC);
+	put_iac(SE);
	}
	#endif

@@ -368,9 +370,9 @@ static void will_charmode(void)
	G.telflags \|= (UF_ECHO \| UF_SGA);
	setConMode();

-	putiac2(DO, TELOPT_ECHO);
-	putiac2(DO, TELOPT_SGA);
-	iacflush();
+	put_iac2(DO, TELOPT_ECHO);
+	put_iac2(DO, TELOPT_SGA);
+	iac_flush();
	}

	static void do_linemode(void)
@@ -379,24 +381,24 @@ static void do_linemode(void)
	G.telflags &= ~(UF_ECHO \| UF_SGA);
	setConMode();

-	putiac2(DONT, TELOPT_ECHO);
-	putiac2(DONT, TELOPT_SGA);
-	iacflush();
+	put_iac2(DONT, TELOPT_ECHO);
+	put_iac2(DONT, TELOPT_SGA);
+	iac_flush();
	}

	static void to_notsup(char c)
	{
	if (G.telwish == WILL)
-	putiac2(DONT, c);
+	put_iac2(DONT, c);
	else if (G.telwish == DO)
-	putiac2(WONT, c);
+	put_iac2(WONT, c);
	}

	static void to_echo(void)
	{
	/* if server requests ECHO, don't agree */
	if (G.telwish == DO) {
-	putiac2(WONT, TELOPT_ECHO);
+	put_iac2(WONT, TELOPT_ECHO);
	return;
	}
	if (G.telwish == DONT)
@@ -412,9 +414,9 @@ static void to_echo(void)
	G.telflags ^= UF_ECHO;

	if (G.telflags & UF_ECHO)
-	putiac2(DO, TELOPT_ECHO);
+	put_iac2(DO, TELOPT_ECHO);
	else
-	putiac2(DONT, TELOPT_ECHO);
+	put_iac2(DONT, TELOPT_ECHO);

	setConMode();
	write_str(1, "\r\n"); /* sudden modec */
@@ -432,9 +434,9 @@ static void to_sga(void)

	G.telflags ^= UF_SGA; /* toggle */
	if (G.telflags & UF_SGA)
-	putiac2(DO, TELOPT_SGA);
+	put_iac2(DO, TELOPT_SGA);
	else
-	putiac2(DONT, TELOPT_SGA);
+	put_iac2(DONT, TELOPT_SGA);
	}

	#if ENABLE_FEATURE_TELNET_TTYPE
@@ -443,9 +445,9 @@ static void to_ttype(void)
	/* Tell server we will (or won't) do TTYPE */

	if (G.ttype)
-	putiac2(WILL, TELOPT_TTYPE);
+	put_iac2(WILL, TELOPT_TTYPE);
	else
-	putiac2(WONT, TELOPT_TTYPE);
+	put_iac2(WONT, TELOPT_TTYPE);
	}
	#endif

@@ -455,9 +457,9 @@ static void to_new_environ(void)
	/* Tell server we will (or will not) do AUTOLOGIN */

	if (G.autologin)
-	putiac2(WILL, TELOPT_NEW_ENVIRON);
+	put_iac2(WILL, TELOPT_NEW_ENVIRON);
	else
-	putiac2(WONT, TELOPT_NEW_ENVIRON);
+	put_iac2(WONT, TELOPT_NEW_ENVIRON);
	}
	#endif

@@ -465,7 +467,7 @@ static void to_new_environ(void)
	static void to_naws(void)
	{
	/* Tell server we will do NAWS */
-	putiac2(WILL, TELOPT_NAWS);
+	put_iac2(WILL, TELOPT_NAWS);
	}
	#endif

@@ -487,7 +489,7 @@ static void telopt(byte c)
	#if ENABLE_FEATURE_AUTOWIDTH
	case TELOPT_NAWS:
	to_naws();
-	putiac_naws(c, G.win_width, G.win_height);
+	put_iac_naws(c, G.win_width, G.win_height);
	break;
	#endif
	default:
@@ -506,12 +508,12 @@ static int subneg(byte c)
	#if ENABLE_FEATURE_TELNET_TTYPE
	else
	if (c == TELOPT_TTYPE)
-	putiac_subopt(TELOPT_TTYPE, G.ttype);
+	put_iac_subopt(TELOPT_TTYPE, G.ttype);
	#endif
	#if ENABLE_FEATURE_TELNET_AUTOLOGIN
	else
	if (c == TELOPT_NEW_ENVIRON)
-	putiac_subopt_autologin();
+	put_iac_subopt_autologin();
	#endif
	break;
	case TS_SUB2:
@@ -611,7 +613,7 @@ int telnet_main(int argc UNUSED_PARAM, char **argv)
	case -1:
	/* error, ignore and/or log something, bay go to loop */
	if (bb_got_signal)
-	conescape();
+	con_escape();
	else
	sleep(1);
	break;
@@ -627,7 +629,7 @@ int telnet_main(int argc UNUSED_PARAM, char **argv)
	if (len <= 0)
	doexit(EXIT_SUCCESS);
	TRACE(0, ("Read con: %d\n", len));
-	handlenetoutput(len);
+	handle_net_output(len);
	}

	#ifdef USE_POLL
@@ -642,7 +644,7 @@ int telnet_main(int argc UNUSED_PARAM, char **argv)
	doexit(EXIT_FAILURE);
	}
	TRACE(0, ("Read netfd (%d): %d\n", netfd, len));
-	handlenetinput(len);
+	handle_net_input(len);
	}
	}
	} /* while (1) */

networking/telnetd.c+51 -7

@@ -74,9 +74,6 @@ static const char *issuefile = "/etc/issue.net";
	past (bf + len) then that IAC will be left unprocessed and *processed
	will be less than len.

-	FIXME - if we mean to send 0xFF to the terminal then it will be escaped,
-	what is the escape character? We aren't handling that situation here.
-
	CR-LF ->'s CR mapping is also done here, for convenience.

	NB: may fail to remove iacs which wrap around buffer!
@@ -159,6 +156,47 @@ remove_iacs(struct tsession ts, int pnum_totty)
	return memmove(ptr - num_totty, ptr0, num_totty);
	}

+	/*
+	* Converting single 0xff into double on output
+	*/
+	static size_t iac_safe_write(int fd, const char *buf, size_t count)
+	{
+	const char *oxff;
+	size_t wr, rc, total;
+
+	total = 0;
+	while (1) {
+	if (count == 0)
+	return total;
+	if (*buf == (char)0xff) {
+	rc = safe_write(fd, "\xff\xff", 2);
+	if (rc != 2)
+	break;
+	buf++;
+	total++;
+	count--;
+	continue;
+	}
+	/* count != 0, buf != 0xff /
+	oxff = memchr(buf, 0xff, count);
+	wr = count;
+	if (oxff)
+	wr = oxff - buf;
+	rc = safe_write(fd, buf, wr);
+	if (rc != wr)
+	break;
+	buf += rc;
+	total += rc;
+	count -= rc;
+	}
+	/* here: rc - result of last short write */
+	if ((ssize_t)rc < 0) { /* error? */
+	if (total == 0)
+	return rc;
+	rc = 0;
+	}
+	return total + rc;
+	}

	static struct tsession *
	make_new_session(
@@ -212,9 +250,15 @@ make_new_session(
	IAC, WILL, TELOPT_ECHO,
	IAC, WILL, TELOPT_SGA
	};
-	memcpy(TS_BUF2, iacs_to_send, sizeof(iacs_to_send));
-	ts->rdidx2 = sizeof(iacs_to_send);
-	ts->size2 = sizeof(iacs_to_send);
+	/* This confuses iac_safe_write(), it will try to duplicate
+	* each IAC... */
+	//memcpy(TS_BUF2, iacs_to_send, sizeof(iacs_to_send));
+	//ts->rdidx2 = sizeof(iacs_to_send);
+	//ts->size2 = sizeof(iacs_to_send);
+	/* So just stuff it into TCP buffer! */
+	safe_write(sock, iacs_to_send, sizeof(iacs_to_send));
+	/ts->rdidx2 = 0; - xzalloc did it! /
+	/ts->size2 = 0;/
	}

	fflush(NULL); /* flush all streams */
@@ -538,7 +582,7 @@ int telnetd_main(int argc UNUSED_PARAM, char **argv)
	if (/ts->size2 &&/ FD_ISSET(ts->sockfd_write, &wrfdset)) {
	/* Write to socket from buffer 2. */
	count = MIN(BUFSIZE - ts->wridx2, ts->size2);
-	count = safe_write(ts->sockfd_write, TS_BUF2 + ts->wridx2, count);
+	count = iac_safe_write(ts->sockfd_write, (void*)(TS_BUF2 + ts->wridx2), count);
	if (count < 0) {
	if (errno == EAGAIN)
	goto skip2;