Adding upstream version 1:8.4p1.upstream/1%8.4p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 231 insertions, 0 deletions

diff --git a/sshpty.c b/sshpty.c
new file mode 100644
index 0000000..bce09e2
--- /dev/null
+++ b/sshpty.c
@@ -0,0 +1,231 @@
+/* $OpenBSD: sshpty.c,v 1.34 2019/07/04 16:20:10 deraadt Exp $ */
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * Allocating a pseudo-terminal, and making it the controlling tty.
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <signal.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#ifdef HAVE_PATHS_H
+# include <paths.h>
+#endif
+#include <pwd.h>
+#include <stdarg.h>
+#include <string.h>
+#include <termios.h>
+#ifdef HAVE_UTIL_H
+# include <util.h>
+#endif
+#include <unistd.h>
+
+#include "sshpty.h"
+#include "log.h"
+#include "misc.h"
+
+#ifdef HAVE_PTY_H
+# include <pty.h>
+#endif
+
+#ifndef O_NOCTTY
+#define O_NOCTTY 0
+#endif
+
+#ifdef __APPLE__
+# include <AvailabilityMacros.h>
+# if (MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5)
+#  define __APPLE_PRIVPTY__
+# endif
+#endif
+
+/*
+ * Allocates and opens a pty.  Returns 0 if no pty could be allocated, or
+ * nonzero if a pty was successfully allocated.  On success, open file
+ * descriptors for the pty and tty sides and the name of the tty side are
+ * returned (the buffer must be able to hold at least 64 characters).
+ */
+
+int
+pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
+{
+	/* openpty(3) exists in OSF/1 and some other os'es */
+	char *name;
+	int i;
+
+	i = openpty(ptyfd, ttyfd, NULL, NULL, NULL);
+	if (i == -1) {
+		error("openpty: %.100s", strerror(errno));
+		return 0;
+	}
+	name = ttyname(*ttyfd);
+	if (!name)
+		fatal("openpty returns device for which ttyname fails.");
+
+	strlcpy(namebuf, name, namebuflen);	/* possible truncation */
+	return 1;
+}
+
+/* Releases the tty.  Its ownership is returned to root, and permissions to 0666. */
+
+void
+pty_release(const char *tty)
+{
+#if !defined(__APPLE_PRIVPTY__) && !defined(HAVE_OPENPTY)
+	if (chown(tty, (uid_t) 0, (gid_t) 0) == -1)
+		error("chown %.100s 0 0 failed: %.100s", tty, strerror(errno));
+	if (chmod(tty, (mode_t) 0666) == -1)
+		error("chmod %.100s 0666 failed: %.100s", tty, strerror(errno));
+#endif /* !__APPLE_PRIVPTY__ && !HAVE_OPENPTY */
+}
+
+/* Makes the tty the process's controlling tty and sets it to sane modes. */
+
+void
+pty_make_controlling_tty(int *ttyfd, const char *tty)
+{
+	int fd;
+
+	/* First disconnect from the old controlling tty. */
+#ifdef TIOCNOTTY
+	fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
+	if (fd >= 0) {
+		(void) ioctl(fd, TIOCNOTTY, NULL);
+		close(fd);
+	}
+#endif /* TIOCNOTTY */
+	if (setsid() == -1)
+		error("setsid: %.100s", strerror(errno));
+
+	/*
+	 * Verify that we are successfully disconnected from the controlling
+	 * tty.
+	 */
+	fd = open(_PATH_TTY, O_RDWR | O_NOCTTY);
+	if (fd >= 0) {
+		error("Failed to disconnect from controlling tty.");
+		close(fd);
+	}
+	/* Make it our controlling tty. */
+#ifdef TIOCSCTTY
+	debug("Setting controlling tty using TIOCSCTTY.");
+	if (ioctl(*ttyfd, TIOCSCTTY, NULL) < 0)
+		error("ioctl(TIOCSCTTY): %.100s", strerror(errno));
+#endif /* TIOCSCTTY */
+#ifdef NEED_SETPGRP
+	if (setpgrp(0,0) < 0)
+		error("SETPGRP %s",strerror(errno));
+#endif /* NEED_SETPGRP */
+	fd = open(tty, O_RDWR);
+	if (fd == -1)
+		error("%.100s: %.100s", tty, strerror(errno));
+	else
+		close(fd);
+
+	/* Verify that we now have a controlling tty. */
+	fd = open(_PATH_TTY, O_WRONLY);
+	if (fd == -1)
+		error("open /dev/tty failed - could not set controlling tty: %.100s",
+		    strerror(errno));
+	else
+		close(fd);
+}
+
+/* Changes the window size associated with the pty. */
+
+void
+pty_change_window_size(int ptyfd, u_int row, u_int col,
+	u_int xpixel, u_int ypixel)
+{
+	struct winsize w;
+
+	/* may truncate u_int -> u_short */
+	w.ws_row = row;
+	w.ws_col = col;
+	w.ws_xpixel = xpixel;
+	w.ws_ypixel = ypixel;
+	(void) ioctl(ptyfd, TIOCSWINSZ, &w);
+}
+
+void
+pty_setowner(struct passwd *pw, const char *tty)
+{
+	struct group *grp;
+	gid_t gid;
+	mode_t mode;
+	struct stat st;
+
+	/* Determine the group to make the owner of the tty. */
+	grp = getgrnam("tty");
+	if (grp == NULL)
+		debug("%s: no tty group", __func__);
+	gid = (grp != NULL) ? grp->gr_gid : pw->pw_gid;
+	mode = (grp != NULL) ? 0620 : 0600;
+
+	/*
+	 * Change owner and mode of the tty as required.
+	 * Warn but continue if filesystem is read-only and the uids match/
+	 * tty is owned by root.
+	 */
+	if (stat(tty, &st) == -1)
+		fatal("stat(%.100s) failed: %.100s", tty,
+		    strerror(errno));
+
+#ifdef WITH_SELINUX
+	ssh_selinux_setup_pty(pw->pw_name, tty);
+#endif
+
+	if (st.st_uid != pw->pw_uid || st.st_gid != gid) {
+		if (chown(tty, pw->pw_uid, gid) == -1) {
+			if (errno == EROFS &&
+			    (st.st_uid == pw->pw_uid || st.st_uid == 0))
+				debug("chown(%.100s, %u, %u) failed: %.100s",
+				    tty, (u_int)pw->pw_uid, (u_int)gid,
+				    strerror(errno));
+			else
+				fatal("chown(%.100s, %u, %u) failed: %.100s",
+				    tty, (u_int)pw->pw_uid, (u_int)gid,
+				    strerror(errno));
+		}
+	}
+
+	if ((st.st_mode & (S_IRWXU|S_IRWXG|S_IRWXO)) != mode) {
+		if (chmod(tty, mode) == -1) {
+			if (errno == EROFS &&
+			    (st.st_mode & (S_IRGRP | S_IROTH)) == 0)
+				debug("chmod(%.100s, 0%o) failed: %.100s",
+				    tty, (u_int)mode, strerror(errno));
+			else
+				fatal("chmod(%.100s, 0%o) failed: %.100s",
+				    tty, (u_int)mode, strerror(errno));
+		}
+	}
+}
+
+/* Disconnect from the controlling tty. */
+void
+disconnect_controlling_tty(void)
+{
+#ifdef TIOCNOTTY
+	int fd;
+
+	if ((fd = open(_PATH_TTY, O_RDWR | O_NOCTTY)) >= 0) {
+		(void) ioctl(fd, TIOCNOTTY, NULL);
+		close(fd);
+	}
+#endif /* TIOCNOTTY */
+}