shell: drop git-cvsserver support by default

The git-cvsserver script is old and largely unmaintained
these days. But git-shell allows untrusted users to run it
out of the box, significantly increasing its attack surface.

Let's drop it from git-shell's list of internal handlers so
that it cannot be run by default.  This is not backwards
compatible. But given the age and development activity on
CVS-related parts of Git, this is likely to impact very few
users, while helping many more (i.e., anybody who runs
git-shell and had no intention of supporting CVS).

There's no configuration mechanism in git-shell for us to
add a boolean and flip it to "off". But there is a mechanism
for adding custom commands, and adding CVS support here is
fairly trivial. Let's document it to give guidance to
anybody who really is still running cvsserver.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 0 insertions, 14 deletions

diff --git a/shell.c b/shell.c
index fe2d314..234b2d4 100644
--- a/shell.c
+++ b/shell.c
@@ -25,19 +25,6 @@ static int do_generic_cmd(const char *me, char *arg)
 	return execv_git_cmd(my_argv);
 }
 
-static int do_cvs_cmd(const char *me, char *arg)
-{
-	const char *cvsserver_argv[3] = {
-		"cvsserver", "server", NULL
-	};
-
-	if (!arg || strcmp(arg, "server"))
-		die("git-cvsserver only handles server: %s", arg);
-
-	setup_path();
-	return execv_git_cmd(cvsserver_argv);
-}
-
 static int is_valid_cmd_name(const char *cmd)
 {
 	/* Test command contains no . or / characters */
@@ -134,7 +121,6 @@ static struct commands {
 	{ "git-receive-pack", do_generic_cmd },
 	{ "git-upload-pack", do_generic_cmd },
 	{ "git-upload-archive", do_generic_cmd },
-	{ "cvs", do_cvs_cmd },
 	{ NULL },
 };