From 9a42c03cb71eaa9d41ba67275de38c997a791c32 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Mon, 11 Sep 2017 11:27:51 -0400 Subject: 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 Signed-off-by: Junio C Hamano --- Documentation/git-shell.txt | 16 ++++++++++++++ shell.c | 14 ------------ t/t9400-git-cvsserver-server.sh | 48 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 64 insertions(+), 14 deletions(-) diff --git a/Documentation/git-shell.txt b/Documentation/git-shell.txt index 2e30a3e42d..54cf2560be 100644 --- a/Documentation/git-shell.txt +++ b/Documentation/git-shell.txt @@ -79,6 +79,22 @@ EOF $ chmod +x $HOME/git-shell-commands/no-interactive-login ---------------- +To enable git-cvsserver access (which should generally have the +`no-interactive-login` example above as a prerequisite, as creating +the git-shell-commands directory allows interactive logins): + +---------------- +$ cat >$HOME/git-shell-commands/cvs <<\EOF +if ! test $# = 1 && test "$1" = "server" +then + echo >&2 "git-cvsserver only handles \"server\"" + exit 1 +fi +exec git cvsserver server +EOF +$ chmod +x $HOME/git-shell-commands/cvs +---------------- + SEE ALSO -------- ssh(1), diff --git a/shell.c b/shell.c index fe2d314593..234b2d4f16 100644 --- a/shell.c +++ b/shell.c @@ -25,19 +25,6 @@ static int do_generic_cmd(const char *me, char *arg) return execv_git_cmd(my_argv); } -static int do_cvs_cmd(const char *me, char *arg) -{ - const char *cvsserver_argv[3] = { - "cvsserver", "server", NULL - }; - - if (!arg || strcmp(arg, "server")) - die("git-cvsserver only handles server: %s", arg); - - setup_path(); - return execv_git_cmd(cvsserver_argv); -} - static int is_valid_cmd_name(const char *cmd) { /* Test command contains no . or / characters */ @@ -134,7 +121,6 @@ static struct commands { { "git-receive-pack", do_generic_cmd }, { "git-upload-pack", do_generic_cmd }, { "git-upload-archive", do_generic_cmd }, - { "cvs", do_cvs_cmd }, { NULL }, }; diff --git a/t/t9400-git-cvsserver-server.sh b/t/t9400-git-cvsserver-server.sh index 432c61d246..c30660d606 100755 --- a/t/t9400-git-cvsserver-server.sh +++ b/t/t9400-git-cvsserver-server.sh @@ -588,4 +588,52 @@ test_expect_success 'cvs annotate' ' test_cmp ../expect ../actual ' +#------------ +# running via git-shell +#------------ + +cd "$WORKDIR" + +test_expect_success 'create remote-cvs helper' ' + write_script remote-cvs <<-\EOF + exec git shell -c "cvs server" + EOF +' + +test_expect_success 'cvs server does not run with vanilla git-shell' ' + ( + cd cvswork && + CVS_SERVER=$WORKDIR/remote-cvs && + export CVS_SERVER && + test_must_fail cvs log merge + ) +' + +test_expect_success 'configure git shell to run cvs server' ' + mkdir "$HOME"/git-shell-commands && + + write_script "$HOME"/git-shell-commands/cvs <<-\EOF && + if ! test $# = 1 && test "$1" = "server" + then + echo >&2 "git-cvsserver only handles \"server\"" + exit 1 + fi + exec git cvsserver server + EOF + + # Should not be used, but part of the recommended setup + write_script "$HOME"/git-shell-commands/no-interactive-login <<-\EOF + echo Interactive login forbidden + EOF +' + +test_expect_success 'cvs server can run with recommended config' ' + ( + cd cvswork && + CVS_SERVER=$WORKDIR/remote-cvs && + export CVS_SERVER && + cvs log merge + ) +' + test_done -- cgit v1.2.1