Re: [PATCH v2] Introduce receive.denyDeletes

> Occasionally, it may be useful to prevent branches from getting deleted from
> a centralized repository, particularly when no administrative access to the
> server is available to undo it via reflog. It also makes
> receive.denyNonFastForwards more useful if it is used for access control
> since it prevents force-updating by deleting and re-creating a ref.
> 
> Signed-off-by: Jan Krüger <jk@jk.gs>
> ---
> Like this, then?

>  Documentation/config.txt |    4 ++++
>  builtin-receive-pack.c   |   12 ++++++++++++
>  t/t5400-send-pack.sh     |   11 +++++++++++
>  3 files changed, 27 insertions(+), 0 deletions(-)
> 
> diff --git a/Documentation/config.txt b/Documentation/config.txt
> index 29369d0..965ed74 100644
> --- a/Documentation/config.txt
> +++ b/Documentation/config.txt
> @@ -1188,6 +1188,10 @@ receive.unpackLimit::
>  	especially on slow filesystems.  If not set, the value of
>  	`transfer.unpackLimit` is used instead.
>  
> +receive.denyDeletes::
> +	If set to true, git-receive-pack will deny a ref update that deletes
> +	the ref. Use this to prevent such a ref deletion via a push.
> +
>  receive.denyNonFastForwards::
>  	If set to true, git-receive-pack will deny a ref update which is
>  	not a fast forward. Use this to prevent such an update via a push,
> diff --git a/builtin-receive-pack.c b/builtin-receive-pack.c
> index 9f60f31..2c0225c 100644
> --- a/builtin-receive-pack.c
> +++ b/builtin-receive-pack.c
> @@ -11,6 +11,7 @@
>  
>  static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
>  
> +static int deny_deletes = 0;
>  static int deny_non_fast_forwards = 0;
>  static int receive_fsck_objects;
>  static int receive_unpack_limit = -1;
> @@ -23,6 +24,11 @@ static int capabilities_sent;
>  
>  static int receive_pack_config(const char *var, const char *value, void *cb)
>  {
> +	if (strcmp(var, "receive.denydeletes") == 0) {
> +		deny_deletes = git_config_bool(var, value);
> +		return 0;
> +	}
> +
>  	if (strcmp(var, "receive.denynonfastforwards") == 0) {
>  		deny_non_fast_forwards = git_config_bool(var, value);
>  		return 0;
> @@ -185,6 +191,12 @@ static const char *update(struct command *cmd)
>  		      "but I can't find it!", sha1_to_hex(new_sha1));
>  		return "bad pack";
>  	}
> +	if (deny_deletes && is_null_sha1(new_sha1) &&
> +	    !is_null_sha1(old_sha1) &&
> +	    !prefixcmp(name, "refs/heads/")) {
> +		error("denying ref deletion for %s", name);
> +		return "deletion prohibited";
> +	}
>  	if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
>  	    !is_null_sha1(old_sha1) &&
>  	    !prefixcmp(name, "refs/heads/")) {
> diff --git a/t/t5400-send-pack.sh b/t/t5400-send-pack.sh
> index 544771d..6fe2f87 100755
> --- a/t/t5400-send-pack.sh
> +++ b/t/t5400-send-pack.sh
> @@ -103,6 +103,17 @@ unset GIT_CONFIG GIT_CONFIG_LOCAL
>  HOME=`pwd`/no-such-directory
>  export HOME ;# this way we force the victim/.git/config to be used.
>  
> +test_expect_failure \
> +	'pushing a delete should be denied with denyDeletes' '
> +	cd victim &&
> +	git config receive.denyDeletes true &&
> +	git branch extra master &&
> +	cd .. &&
> +	test -f victim/.git/refs/heads/extra &&
> +	test_must_fail git send-pack ./victim/.git/ :extra master
> +'
> +rm -f victim/.git/refs/heads/extra
> +
>  test_expect_success \
>          'pushing with --force should be denied with denyNonFastforwards' '
>  	cd victim &&
> -- 
> 1.6.0.3.524.g86cf.dirty