Author: ed
Date: Mon Oct 27 05:28:08 2008
New Revision: 184322
URL: http://svn.freebsd.org/changeset/base/184322
Log:
MFC r183565:
Small cleanups to openpty().
- Pass O_NOCTTY to posix_openpt(2). This makes the implementation work
consistently on implementations that make the PTY the controlling TTY
by default.
- Call unlockpt() before opening the slave device. POSIX mentions that
de slave device should only be opened after grantpt() and unlockpt()
have been called.
- Replace some redundant code by a label.
As a safety net, add a call to revoke() to unlockpt(). All applications
out there use openpty(), explicitly call revoke() or implement their own
PTY allocation routines. Adding the call to unlockpt() won't hurt, but
will prevent foot-shooting.
Reviewed by: jhb, kib
Approved by: re
Modified:
releng/6.4/lib/libc/ (props changed)
releng/6.4/lib/libc/stdlib/grantpt.3
releng/6.4/lib/libc/stdlib/grantpt.c
releng/6.4/lib/libc/sys/ (props changed)
releng/6.4/lib/libutil/ (props changed)
releng/6.4/lib/libutil/pty.c
Modified: releng/6.4/lib/libc/stdlib/grantpt.3
==============================================================================
--- releng/6.4/lib/libc/stdlib/grantpt.3 Mon Oct 27 05:23:40 2008 (r184321)
+++ releng/6.4/lib/libc/stdlib/grantpt.3 Mon Oct 27 05:28:08 2008 (r184322)
@@ -212,11 +212,6 @@ and
functions appeared in
.Fx 5.0 .
.Sh NOTES
-The purpose of the
-.Fn unlockpt
-function has no meaning in
-.Fx .
-.Pp
The flag
.Dv O_NOCTTY
is included for compatibility; in
Modified: releng/6.4/lib/libc/stdlib/grantpt.c
==============================================================================
--- releng/6.4/lib/libc/stdlib/grantpt.c Mon Oct 27 05:23:40 2008 (r184321)
+++ releng/6.4/lib/libc/stdlib/grantpt.c Mon Oct 27 05:28:08 2008 (r184322)
@@ -237,14 +237,20 @@ invalid:
int
unlockpt(int fildes)
{
+ const char *slave;
/*
- * Unlocking a master/slave pseudo-terminal pair has no meaning in a
- * non-streams PTY environment. However, we do ensure fildes is a
- * valid master pseudo-terminal device.
+ * Even though unlocking a PTY has no meaning in a non-streams
+ * PTY environment, make this function call revoke() to ensure
+ * the PTY slave device is not being evesdropped.
*/
- if (ptsname(fildes) == NULL)
+ if ((slave = ptsname(fildes)) == NULL)
return (-1);
+ if (revoke(slave) == -1) {
+ errno = EINVAL;
+ return (-1);
+ }
+
return (0);
}
Modified: releng/6.4/lib/libutil/pty.c
==============================================================================
--- releng/6.4/lib/libutil/pty.c Mon Oct 27 05:23:40 2008 (r184321)
+++ releng/6.4/lib/libutil/pty.c Mon Oct 27 05:28:08 2008 (r184322)
@@ -60,37 +60,26 @@ openpty(int *amaster, int *aslave, char
const char *slavename;
int master, slave;
- master = posix_openpt(O_RDWR);
+ master = posix_openpt(O_RDWR|O_NOCTTY);
if (master == -1)
return (-1);
- if (grantpt(master) == -1) {
- close(master);
- return (-1);
- }
+ if (grantpt(master) == -1)
+ goto bad;
+
+ if (unlockpt(master) == -1)
+ goto bad;
slavename = ptsname(master);
- if (slavename == NULL) {
- close(master);
- return (-1);
- }
+ if (slavename == NULL)
+ goto bad;
- if (revoke(slavename) == -1) {
- close(master);
- return (-1);
- }
+ if (revoke(slavename) == -1)
+ goto bad;
slave = open(slavename, O_RDWR);
- if (slave == -1) {
- close(master);
- return (-1);
- }
-
- if (unlockpt(master) == -1) {
- close(master);
- close(slave);
- return (-1);
- }
+ if (slave == -1)
+ goto bad;
*amaster = master;
*aslave = slave;
@@ -103,6 +92,9 @@ openpty(int *amaster, int *aslave, char
ioctl(slave, TIOCSWINSZ, (char *)winp);
return (0);
+
+bad: close(master);
+ return (-1);
}
int