upstream: Add support for "Match sessiontype" to ssh_config. Allows

matching on the type of session requested, either "shell" for interactive
sessions, "exec" for command execution sessions, "subsystem" for subsystem
requests, such as sftp, or "none" for transport/forwarding-only sessions.

ok markus@

OpenBSD-Commit-ID: eff5c001aecb2283d36639cfb28c0935a8bfd468

diff --git a/readconf.c b/readconf.c
index 72392d01a26bea5cbb2a3b6f23bf54896015b71c..10adaaaa8c37617fe28ac63e1bb22ca0f52b8041 100644 (file)
--- a/readconf.c
+++ b/readconf.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: readconf.c,v 1.395 2025/02/15 01:48:30 djm Exp $ */
+/* $OpenBSD: readconf.c,v 1.396 2025/02/15 01:50:47 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -856,6 +856,19 @@ match_cfg_line(Options *options, const char *full_line, int *acp, char ***avp,
                            match_pattern_list(criteria, arg, 0) == 1;
                        if (r == (negate ? 1 : 0))
                                this_result = result = 0;
+               } else if (strcasecmp(attrib, "sessiontype") == 0) {
+                       if (options->session_type == SESSION_TYPE_SUBSYSTEM)
+                               criteria = xstrdup("subsystem");
+                       else if (options->session_type == SESSION_TYPE_NONE)
+                               criteria = xstrdup("none");
+                       else if (remote_command != NULL &&
+                           *remote_command != '\0')
+                               criteria = xstrdup("exec");
+                       else
+                               criteria = xstrdup("shell");
+                       r = match_pattern_list(criteria, arg, 0) == 1;
+                       if (r == (negate ? 1 : 0))
+                               this_result = result = 0;
                } else if (strcasecmp(attrib, "exec") == 0) {
                        if ((cmd = expand_match_exec_or_include_path(arg,
                            options, pw, host_arg, original_host,

diff --git a/ssh_config.5 b/ssh_config.5
index 857cabbe851d0d2b1f717a8d5790181ba98fa33e..6fff9c74ad933c6d84a1e32f3b57e8c0e72fce3b 100644 (file)
--- a/ssh_config.5
+++ b/ssh_config.5
@@ -33,7 +33,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.\" $OpenBSD: ssh_config.5,v 1.408 2025/02/15 01:48:30 djm Exp $
+.\" $OpenBSD: ssh_config.5,v 1.409 2025/02/15 01:50:47 djm Exp $
 .Dd $Mdocdate: February 15 2025 $
 .Dt SSH_CONFIG 5
 .Os
@@ -255,6 +255,24 @@ keyword matches against the name of the local user running
 (this keyword may be useful in system-wide
 .Nm
 files).
+.Pp
+Finally, the
+.Cm sessiontype
+keyword matches the requested session type, which may be one of
+.Cm shell
+for interactive sessions,
+.Cm exec
+for command execution sessions,
+.Cm subsystem
+for subsystem invocations such as
+.Xr sftp 1 ,
+or
+.Cm none
+for transport-only sessions, such as when
+.Xr ssh 1
+is started with the
+.Fl N
+flag.
 .It Cm AddKeysToAgent
 Specifies whether keys should be automatically added to a running
 .Xr ssh-agent 1 .