X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/05862919589ac3f2a40075aea36fbcbc2cf77948..cb56e28355367ebae06707035dee40156c4ee512:/usr/src/usr.bin/tip/tip.c

diff --git a/usr/src/usr.bin/tip/tip.c b/usr/src/usr.bin/tip/tip.c
index 898ec2397f..4e22ace388 100644
--- a/usr/src/usr.bin/tip/tip.c
+++ b/usr/src/usr.bin/tip/tip.c
@@ -1,6 +1,29 @@
+/*
+ * Copyright (c) 1983 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+char copyright[] =
+"@(#) Copyright (c) 1983 The Regents of the University of California.\n\
+ All rights reserved.\n";
+#endif /* not lint */
+
 #ifndef lint
-static char sccsid[] = "@(#)tip.c	4.15 (Berkeley) %G%";
-#endif
+static char sccsid[] = "@(#)tip.c	5.12 (Berkeley) %G%";
+#endif /* not lint */
 
 /*
  * tip - UNIX link to other systems
@@ -9,6 +32,7 @@ static char sccsid[] = "@(#)tip.c	4.15 (Berkeley) %G%";
  *  cu phone-number [-s speed] [-l line] [-a acu]
  */
 #include "tip.h"
+#include "pathnames.h"
 
 /*
  * Baud rate mapping table
@@ -19,11 +43,11 @@ int bauds[] = {
 };
 
 int	disc = OTTYDISC;		/* tip normally runs this way */
-int	intprompt();
-int	timeout();
-int	cleanup();
+void	intprompt();
+void	timeout();
+void	cleanup();
 char	*sname();
-extern char *sprintf();
+char	PNbuf[256];			/* This limits the size of a number */
 
 main(argc, argv)
 	char *argv[];
@@ -33,9 +57,13 @@ main(argc, argv)
 	register char *p;
 	char sbuf[12];
 
+	gid = getgid();
+	egid = getegid();
+	uid = getuid();
+	euid = geteuid();
 	if (equal(sname(argv[0]), "cu")) {
-		cumain(argc, argv);
 		cumode = 1;
+		cumain(argc, argv);
 		goto cucommon;
 	}
 
@@ -70,17 +98,30 @@ main(argc, argv)
 
 	if (system == NOSTR)
 		goto notnumber;
+	if (isalpha(*system))
+		goto notnumber;
+	/*
+	 * System name is really a phone number...
+	 * Copy the number then stomp on the original (in case the number
+	 *	is private, we don't want 'ps' or 'w' to find it).
+	 */
+	if (strlen(system) > sizeof PNbuf - 1) {
+		fprintf(stderr, "tip: phone number too long (max = %d bytes)\n",
+			sizeof PNbuf - 1);
+		exit(1);
+	}
+	strncpy( PNbuf, system, sizeof PNbuf - 1 );
 	for (p = system; *p; p++)
-		if (isalpha(*p))
-			goto notnumber;
-	PN = system;		/* system name is really a phone number */
-	system = sprintf(sbuf, "tip%d", BR);
+		*p = '\0';
+	PN = PNbuf;
+	(void)sprintf(sbuf, "tip%d", BR);
+	system = sbuf;
 
 notnumber:
-	signal(SIGINT, cleanup);
-	signal(SIGQUIT, cleanup);
-	signal(SIGHUP, cleanup);
-	signal(SIGTERM, cleanup);
+	(void)signal(SIGINT, cleanup);
+	(void)signal(SIGQUIT, cleanup);
+	(void)signal(SIGHUP, cleanup);
+	(void)signal(SIGTERM, cleanup);
 
 	if ((i = hunt(system)) == 0) {
 		printf("all ports busy\n");
@@ -88,35 +129,35 @@ notnumber:
 	}
 	if (i == -1) {
 		printf("link down\n");
-		delock(uucplock);
+		(void)uu_unlock(uucplock);
 		exit(3);
 	}
 	setbuf(stdout, NULL);
 	loginit();
-	/*
-	 * Now that we have the logfile and the ACU open
-	 *  return to the real uid and gid.  These things will
-	 *  be closed on exit.  Note that we can't run as root,
-	 *  because locking mechanism on the tty and the accounting
-	 *  will be bypassed.
-	 */
-	setgid(getgid());
-	setuid(getuid());
 
 	/*
 	 * Kludge, their's no easy way to get the initialization
 	 *   in the right order, so force it here
 	 */
 	if ((PH = getenv("PHONES")) == NOSTR)
-		PH = "/etc/phones";
+		PH = _PATH_PHONES;
 	vinit();				/* init variables */
-	setparity();				/* set the parity table */
+	setparity("even");			/* set the parity table */
 	if ((i = speed(number(value(BAUDRATE)))) == NULL) {
 		printf("tip: bad baud rate %d\n", number(value(BAUDRATE)));
-		delock(uucplock);
+		(void)uu_unlock(uucplock);
 		exit(3);
 	}
 
+	/*
+	 * Now that we have the logfile and the ACU open
+	 *  return to the real uid and gid.  These things will
+	 *  be closed on exit.  Swap real and effective uid's
+	 *  so we can get the original permissions back
+	 *  for removing the uucp lock.
+	 */
+	user_uid();
+
 	/*
 	 * Hardwired connections require the
 	 *  line speed set before they make any transmissions
@@ -126,7 +167,8 @@ notnumber:
 		ttysetup(i);
 	if (p = connect()) {
 		printf("\07%s\n[EOT]\n", p);
-		delock(uucplock);
+		daemon_uid();
+		(void)uu_unlock(uucplock);
 		exit(1);
 	}
 	if (!HW)
@@ -136,6 +178,7 @@ cucommon:
 	 * From here down the code is shared with
 	 * the "cu" version of tip.
 	 */
+
 	ioctl(0, TIOCGETP, (char *)&defarg);
 	ioctl(0, TIOCGETC, (char *)&defchars);
 	ioctl(0, TIOCGLTC, (char *)&deflchars);
@@ -150,11 +193,11 @@ cucommon:
 	raw();
 
 	pipe(fildes); pipe(repdes);
-	signal(SIGALRM, timeout);
+	(void)signal(SIGALRM, timeout);
 
 	/*
 	 * Everything's set up now:
-	 *	connection established (hardwired or diaulup)
+	 *	connection established (hardwired or dialup)
 	 *	line conditioned (baud rate, mode, etc.)
 	 *	internal data structures (variables)
 	 * so, fork one process for local side and one for remote.
@@ -167,15 +210,53 @@ cucommon:
 	/*NOTREACHED*/
 }
 
+void
 cleanup()
 {
 
-	delock(uucplock);
+	daemon_uid();
+	(void)uu_unlock(uucplock);
 	if (odisc)
 		ioctl(0, TIOCSETD, (char *)&odisc);
 	exit(0);
 }
 
+/*
+ * Muck with user ID's.  We are setuid to the owner of the lock
+ * directory when we start.  user_uid() reverses real and effective
+ * ID's after startup, to run with the user's permissions.
+ * daemon_uid() switches back to the privileged uid for unlocking.
+ * Finally, to avoid running a shell with the wrong real uid,
+ * shell_uid() sets real and effective uid's to the user's real ID.
+ */
+static int uidswapped;
+
+user_uid()
+{
+	if (uidswapped == 0) {
+		setregid(egid, gid);
+		setreuid(euid, uid);
+		uidswapped = 1;
+	}
+}
+
+daemon_uid()
+{
+
+	if (uidswapped) {
+		setreuid(uid, euid);
+		setregid(gid, egid);
+		uidswapped = 0;
+	}
+}
+
+shell_uid()
+{
+
+	setreuid(uid, uid);
+	setregid(gid, gid);
+}
+
 /*
  * put the controlling keyboard into raw mode
  */
@@ -213,11 +294,11 @@ prompt(s, p)
 	register char *p;
 {
 	register char *b = p;
-	int (*oint)(), (*oquit)();
+	sig_t oint, oquit;
 
 	stoprompt = 0;
 	oint = signal(SIGINT, intprompt);
-	oint = signal(SIGQUIT, SIG_IGN);
+	oquit = signal(SIGQUIT, SIG_IGN);
 	unraw();
 	printf("%s", s);
 	if (setjmp(promptbuf) == 0)
@@ -226,18 +307,19 @@ prompt(s, p)
 	*p = '\0';
 
 	raw();
-	signal(SIGINT, oint);
-	signal(SIGQUIT, oint);
+	(void)signal(SIGINT, oint);
+	(void)signal(SIGQUIT, oquit);
 	return (stoprompt || p == b);
 }
 
 /*
  * Interrupt service routine during prompting
  */
+void
 intprompt()
 {
 
-	signal(SIGINT, SIG_IGN);
+	(void)signal(SIGINT, SIG_IGN);
 	stoprompt = 1;
 	printf("\r\n");
 	longjmp(promptbuf, 1);
@@ -301,7 +383,7 @@ escape()
 	gch = (getchar()&0177);
 	for (p = etable; p->e_char; p++)
 		if (p->e_char == gch) {
-			if ((p->e_flags&PRIV) && getuid())
+			if ((p->e_flags&PRIV) && uid)
 				continue;
 			printf("%s", ctrl(c));
 			(*p->e_func)(gch);
@@ -397,7 +479,7 @@ help(c)
 
 	printf("%c\r\n", c);
 	for (p = etable; p->e_char; p++) {
-		if ((p->e_flags&PRIV) && getuid())
+		if ((p->e_flags&PRIV) && uid)
 			continue;
 		printf("%2s", ctrl(character(value(ESCAPE))));
 		printf("%-2s %c   %s\r\n", ctrl(p->e_char),
@@ -438,6 +520,7 @@ sname(s)
 }
 
 static char partab[0200];
+static int bits8;
 
 /*
  * Do a write to the remote machine with the correct parity.
@@ -451,27 +534,40 @@ pwrite(fd, buf, n)
 {
 	register int i;
 	register char *bp;
+	extern int errno;
 
 	bp = buf;
-	for (i = 0; i < n; i++) {
-		*bp = partab[(*bp) & 0177];
-		bp++;
+	if (bits8 == 0)
+		for (i = 0; i < n; i++) {
+			*bp = partab[(*bp) & 0177];
+			bp++;
+		}
+	if (write(fd, buf, n) < 0) {
+		if (errno == EIO)
+			abort("Lost carrier.");
+		/* this is questionable */
+		perror("write");
 	}
-	write(fd, buf, n);
 }
 
 /*
  * Build a parity table with appropriate high-order bit.
  */
-setparity()
+setparity(defparity)
+	char *defparity;
 {
 	register int i;
 	char *parity;
 	extern char evenpartab[];
 
 	if (value(PARITY) == NOSTR)
-		value(PARITY) = "even";
+		value(PARITY) = defparity;
 	parity = value(PARITY);
+	if (equal(parity, "none")) {
+		bits8 = 1;
+		return;
+	} else
+		bits8 = 0;
 	for (i = 0; i < 0200; i++)
 		partab[i] = evenpartab[i];
 	if (equal(parity, "even"))
@@ -481,7 +577,7 @@ setparity()
 			partab[i] ^= 0200;	/* reverse bit 7 */
 		return;
 	}
-	if (equal(parity, "none") || equal(parity, "zero")) {
+	if (equal(parity, "zero")) {
 		for (i = 0; i < 0200; i++)
 			partab[i] &= ~0200;	/* turn off bit 7 */
 		return;