No need to use pseudo-cbreak mode now that we use pipes when stdout is

not a tty.  Instead, check whether stdin is a tty and if not, delay
setting the tty to raw mode until the command tries to access it itself
(and receives SIGTTIN or SIGTTOU).

plugins/sudoers/sudoreplay.c

@@ -150,7 +150,7 @@ static int stack_top;
 
 extern time_t get_date(char *);
 extern char *get_timestr(time_t, int);
-extern int term_raw(int, int, int);
+extern int term_raw(int, int);
 extern int term_restore(int, int);
 extern void zero_bytes(volatile void *, size_t);
 void cleanup(int);
@@ -297,7 +297,7 @@ main(int argc, char *argv[])
 	ch = fcntl(STDIN_FILENO, F_GETFL, 0);
 	if (ch != -1)
 	    (void) fcntl(STDIN_FILENO, F_SETFL, ch | O_NONBLOCK);
-	if (!term_raw(STDIN_FILENO, 0, 1))
+	if (!term_raw(STDIN_FILENO, 1))
 	    error(1, "cannot set tty to raw mode");
     }
     fdsr = (fd_set *)emalloc2(howmany(STDOUT_FILENO + 1, NFDBITS),

src/script.c

@@ -87,8 +87,7 @@
 #define SFD_USERTTY	5
 
 #define TERM_COOKED	0
-#define TERM_CBREAK	1
+#define TERM_RAW	1
-#define TERM_RAW	2
 
 #if !defined(TIOCGSIZE) && defined(TIOCGWINSZ)
 # define TIOCGSIZE	TIOCGWINSZ
@@ -108,7 +107,7 @@ struct io_buffer {
 };
 
 static int script_fds[6] = { -1, -1, -1, -1, -1, -1};
-static int ttyout = TRUE;
+static int ttyin = TRUE;
 
 static sig_atomic_t recvsig[NSIG];
 static sig_atomic_t ttymode = TERM_COOKED;
@@ -296,7 +295,7 @@ suspend_parent(int signo, int fd, struct io_buffer *iobufs)
 	if (foreground) {
 	    if (ttymode != TERM_RAW) {
 		do {
-		    n = term_raw(script_fds[SFD_USERTTY], !ttyout, 0);
+		    n = term_raw(script_fds[SFD_USERTTY], 0);
 		} while (!n && errno == EINTR);
 		ttymode = TERM_RAW;
 	    }
@@ -335,10 +334,9 @@ suspend_parent(int signo, int fd, struct io_buffer *iobufs)
 
 	if (ttymode != TERM_COOKED) {
 	    if (foreground) {
-		/* Set raw/cbreak mode. */
+		/* Set raw mode. */
 		do {
-		    n = term_raw(script_fds[SFD_USERTTY], !ttyout,
+		    n = term_raw(script_fds[SFD_USERTTY], 0);
-			ttymode == TERM_CBREAK);
 		} while (!n && errno == EINTR);
 	    } else {
 		/* Background process, no access to tty. */
@@ -565,6 +563,7 @@ script_execve(struct command_details *details, char *argv[], char *envp[],
 	 */
 	memset(io_pipe, 0, sizeof(io_pipe));
 	if (!isatty(STDIN_FILENO)) {
+	    ttyin = FALSE;
 	    if (pipe(io_pipe[STDIN_FILENO]) != 0)
 		error(1, "unable to create pipe");
 	    iobufs = io_buf_new(STDIN_FILENO, io_pipe[STDIN_FILENO][1],
@@ -572,7 +571,6 @@ script_execve(struct command_details *details, char *argv[], char *envp[],
 	    script_fds[SFD_STDIN] = io_pipe[STDIN_FILENO][0];
 	}
 	if (!isatty(STDOUT_FILENO)) {
-	    ttyout = FALSE;
 	    if (pipe(io_pipe[STDOUT_FILENO]) != 0)
 		error(1, "unable to create pipe");
 	    iobufs = io_buf_new(io_pipe[STDOUT_FILENO][0], STDOUT_FILENO,
@@ -603,14 +601,15 @@ script_execve(struct command_details *details, char *argv[], char *envp[],
 		sync_ttysize(script_fds[SFD_USERTTY], script_fds[SFD_SLAVE]);
 	    }
 
-	    /* Start out in raw mode is stdout is a tty. */
+	    /* Start out in raw mode is stdin is a tty. */
-	    ttymode = ttyout ? TERM_RAW : TERM_CBREAK;
+	    if (ttyin) {
-	    do {
+		ttymode = TERM_RAW;
-		n = term_raw(script_fds[SFD_USERTTY], !ttyout,
+		do {
-		    ttymode == TERM_CBREAK);
+		    n = term_raw(script_fds[SFD_USERTTY], 0);
-	    } while (!n && errno == EINTR);
+		} while (!n && errno == EINTR);
-	    if (!n)
+		if (!n)
-		error(1, "Can't set terminal to raw mode");
+		    error(1, "Can't set terminal to raw mode");
+	    }
 	}
     }
 
@@ -738,7 +737,7 @@ script_execve(struct command_details *details, char *argv[], char *envp[],
 		    FD_SET(iob->rfd, fdsr);
 	    }
 	    if (iob->wfd != -1 &&
-		(ttymode == TERM_RAW || iob->wfd != script_fds[SFD_USERTTY])) {
+		(foreground || iob->wfd != script_fds[SFD_USERTTY])) {
 		if (iob->len > iob->off)
 		    FD_SET(iob->wfd, fdsw);
 	    }
@@ -971,7 +970,13 @@ script_child(const char *path, char *argv[], char *envp[], int backchannel, int
 	close(n);
 #endif
 
-    if (foreground && !ttyout)
+    /*
+     * If stdin is not a tty, start command in the background since
+     * it might be part of a pipeline that reads from /dev/tty.
+     * In this case, we rely on the command receiving SIGTTOU or SIGTTIN
+     * when it needs access to the controlling tty.
+     */
+    if (foreground && !ttyin)
 	foreground = 0;
 
     /* Start command and wait for it to stop or exit */
@@ -1012,7 +1017,6 @@ script_child(const char *path, char *argv[], char *envp[], int backchannel, int
     close(errpipe[1]);
 
     /* If any of stdin/stdout/stderr are pipes, close them in parent. */
-    /* XXX - close other end too */
     if (script_fds[SFD_STDIN] != script_fds[SFD_SLAVE])
 	close(script_fds[SFD_STDIN]);
     if (script_fds[SFD_STDOUT] != script_fds[SFD_SLAVE])

src/sudo.h

@@ -178,7 +178,7 @@ void script_setup(uid_t);
 int term_cbreak(int);
 int term_copy(int, int);
 int term_noecho(int);
-int term_raw(int, int, int);
+int term_raw(int, int);
 int term_restore(int, int);
 
 /* fmt_string.h */

src/term.c

@@ -116,7 +116,7 @@ term_noecho(int fd)
 }
 
 int
-term_raw(int fd, int opost, int isig)
+term_raw(int fd, int isig)
 {
     struct termios term;
 
@@ -130,9 +130,6 @@ term_raw(int fd, int opost, int isig)
     if (isig)
 	SET(term.c_lflag, ISIG);
     CLR(term.c_iflag, ICRNL | IGNCR | INLCR | IUCLC | IXON);
-    /* Only retain output post-processing opost flag set. */
-    if (!opost)
-	CLR(term.c_oflag, OPOST);
     if (tcsetattr(fd, TCSADRAIN|TCSASOFT, &term) == 0) {
 	changed = 1;
     	return(1);