diff options
Diffstat (limited to 'usr.bin')
| -rw-r--r-- | usr.bin/cu/command.c | 8 | ||||
| -rw-r--r-- | usr.bin/cu/cu.1 | 17 | ||||
| -rw-r--r-- | usr.bin/cu/cu.c | 14 | ||||
| -rw-r--r-- | usr.bin/cu/cu.h | 3 |
4 files changed, 34 insertions, 8 deletions
diff --git a/usr.bin/cu/command.c b/usr.bin/cu/command.c index 9ae8e9adf9c..c07fe73aeca 100644 --- a/usr.bin/cu/command.c +++ b/usr.bin/cu/command.c @@ -1,4 +1,4 @@ -/* $OpenBSD: command.c,v 1.15 2015/10/05 23:15:31 nicm Exp $ */ +/* $OpenBSD: command.c,v 1.16 2017/12/10 01:03:46 deraadt Exp $ */ /* * Copyright (c) 2012 Nicholas Marriott <nicm@openbsd.org> @@ -28,6 +28,7 @@ #include <signal.h> #include <stdlib.h> #include <stdio.h> +#include <string.h> #include <unistd.h> #include "cu.h" @@ -222,6 +223,11 @@ start_record(void) void do_command(char c) { + if (restricted && strchr("CRX$>", c) != NULL) { + cu_warnx("~%c command is not allowed in restricted mode", c); + return; + } + switch (c) { case '.': case '\004': /* ^D */ diff --git a/usr.bin/cu/cu.1 b/usr.bin/cu/cu.1 index 2f1a3c836c6..3f47560afde 100644 --- a/usr.bin/cu/cu.1 +++ b/usr.bin/cu/cu.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: cu.1,v 1.15 2015/05/18 09:35:05 nicm Exp $ +.\" $OpenBSD: cu.1,v 1.16 2017/12/10 01:03:46 deraadt Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -27,7 +27,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.Dd $Mdocdate: May 18 2015 $ +.Dd $Mdocdate: December 10 2017 $ .Dt CU 1 .Os .Sh NAME @@ -35,7 +35,7 @@ .Nd serial terminal emulator .Sh SYNOPSIS .Nm -.Op Fl d +.Op Fl dr .Op Fl l Ar line .Op Fl s Ar speed | Fl Ar speed .Nm @@ -55,6 +55,11 @@ The options are as follows: Specify that the line is directly connected and .Nm should not allow the driver to block waiting for a carrier to be detected. +.It Fl r +Starts +.Nm +in restricted mode. +This prevents all local filesystem operations and command executions. .It Fl l Ar line Specify the line to use. Either of the forms like @@ -114,6 +119,7 @@ process to the remote host. The command string sent to the local .Ux system is processed by the shell. +This command is not allowed in restricted mode. .It Ic ~# Send a .Dv BREAK @@ -132,16 +138,21 @@ file descriptors: 1 \*(Lt-\*(Gt remote tty out 2 \*(Lt-\*(Gt local tty stderr .Ed +.Pp +This command is not allowed in restricted mode. .It Ic ~D Deassert the data terminal ready (DTR) line briefly. +This command is not allowed in restricted mode. .It Ic ~R Record all output from the remote system to a file. If the given file already exists, it is appended to. If no file is specified, any existing recording is stopped. +This command is not allowed in restricted mode. .It Ic ~S Change the speed of the connection. .It Ic ~X Send a file with the XMODEM protocol. +This command is not allowed in restricted mode. .It Ic ~? Get a summary of the tilde escapes. .El diff --git a/usr.bin/cu/cu.c b/usr.bin/cu/cu.c index 8d1935a11c2..03a2df4181f 100644 --- a/usr.bin/cu/cu.c +++ b/usr.bin/cu/cu.c @@ -1,4 +1,4 @@ -/* $OpenBSD: cu.c,v 1.25 2017/08/22 16:32:37 mestre Exp $ */ +/* $OpenBSD: cu.c,v 1.26 2017/12/10 01:03:46 deraadt Exp $ */ /* * Copyright (c) 2012 Nicholas Marriott <nicm@openbsd.org> @@ -42,6 +42,7 @@ struct termios saved_tio; struct bufferevent *input_ev; struct bufferevent *output_ev; int is_direct = -1; +int restricted = 0; const char *line_path = NULL; int line_speed = -1; int line_fd; @@ -66,7 +67,7 @@ void try_remote(const char *, const char *, const char *); __dead void usage(void) { - fprintf(stderr, "usage: %s [-d] [-l line] [-s speed | -speed]\n", + fprintf(stderr, "usage: %s [-dr] [-l line] [-s speed | -speed]\n", __progname); fprintf(stderr, " %s [host]\n", __progname); exit(1); @@ -100,11 +101,16 @@ main(int argc, char **argv) errx(1, "speed asprintf"); } - while ((opt = getopt(argc, argv, "dl:s:")) != -1) { + while ((opt = getopt(argc, argv, "drl:s:")) != -1) { switch (opt) { case 'd': is_direct = 1; break; + case 'r': + if (pledge("stdio rpath wpath tty", NULL) == -1) + err(1, "pledge"); + restricted = 1; + break; case 'l': line_path = optarg; break; @@ -162,6 +168,8 @@ main(int argc, char **argv) line_fd = open(line_path, flags); if (line_fd < 0) err(1, "open(\"%s\")", line_path); + if (restricted && pledge("stdio tty", NULL) == -1) + err(1, "pledge"); if (!isatty(line_fd)) err(1, "%s", line_path); if (ioctl(line_fd, TIOCEXCL) != 0) diff --git a/usr.bin/cu/cu.h b/usr.bin/cu/cu.h index 10745bc037a..2a7ca45d414 100644 --- a/usr.bin/cu/cu.h +++ b/usr.bin/cu/cu.h @@ -1,4 +1,4 @@ -/* $OpenBSD: cu.h,v 1.7 2015/10/05 23:15:31 nicm Exp $ */ +/* $OpenBSD: cu.h,v 1.8 2017/12/10 01:03:46 deraadt Exp $ */ /* * Copyright (c) 2012 Nicholas Marriott <nicm@openbsd.org> @@ -23,6 +23,7 @@ void do_command(char); /* cu.c */ +extern int restricted; extern FILE *record_file; extern struct termios saved_tio; extern int line_fd; |