From nobody Thu Dec 21 13:43:29 2023 X-Original-To: dev-commits-src-branches@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Sws8L2x23z54pqy; Thu, 21 Dec 2023 13:43:30 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Sws8K5mz2z4NMD; Thu, 21 Dec 2023 13:43:29 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1703166209; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7DDbAx63JVc2346EtTaC3uAGsLi8aA1FcquvQrRQIiQ=; b=hJB6HC7vtF6arNuJdqyl/8mkOG1pj1DJy1TluMZSTgQft1f/D9inN90kkY6dPhNvMd+VM8 de1iLbrjpgF/aLHQ37+wMNfgW8SlKGCvzntqaGxoYTqtiuJEDqXXDBsWw+sjgIQxzaf6IE mxGH0h4YQQFeztUIqNBID660dg8B9LMLSl3I7e8rGf+dRBZt7KZfBCSxOHRATuANUvMhZ+ IztiOKzHyQuvXQkCadoHX0XFAAjgOjr/KNYXDI5YSOHqDSpLrtJiLa86bapK+HVOay3hLD eFF+WbqKd2EZNPRw13/Dj5Z2R+9O5c9qDsJc1WSs0a4ARgnEI66fAgRhzymrWQ== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1703166209; a=rsa-sha256; cv=none; b=gEx+mV9pJPVTKJLC0kLJrQzvHyOX6Q1SB1TmJqoq6kzBYHV9gnshBeTyR/GvOULevZejQI RNiHX15lDVFGjHSIVJbS4lUUGCEosN2eyCkpPOa0rQpwZWNxuOLKy49W8tmfU3h3Pp9QJK vgehDA2E0sPdpvFQiJ09DH1m8TnGZ9O+5bnPwh2yBFTNL/hSt3WP1HN18ETF5lBmMevCZV uuPUZhMhvsNsE73dAF7DdoZhXd+GEcYpMGZYTrR4OJf8U0j1ZPRvhkKNn+LPfdgkZDOgpE YAbXtJOkbeIYnhhOKbTdbPiVdnREpE32YbQl88YIk38uiqFj3f6Lbb+89WwBbg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1703166209; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7DDbAx63JVc2346EtTaC3uAGsLi8aA1FcquvQrRQIiQ=; b=MsHXuHAlKrjVwyt5Ztv7Iro3TKAzkATrPj2Ij+qWEFlZxC7CWRHeT3l6DZdlZ4KhASMgFj x01gbWgwxyrfUizaolZ+3tV2jWP8B2ANzQiWXXe5nhePMfJCVzVQf96Yosoly9VuelNFyq t4ZQ3/S4ft8nzJulx7YH1R30XKGr3q1BMtQ7OhoqB0EcFypkUb1OsMZR0/URvc6My7NK3S /F1ep/7Bn4/hj2+gpER+v/pu4YulGXR4k3DNQpfwTfGbbvJZMgtVvvlBDBvZgNc/gS1J28 d3QY7p3pD8pgbqOA0rUxDI2tQrwi2qCtZdSvmzROzzAeSLp8NRzejZOsvovh1A== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4Sws8K4ZRTzb5r; Thu, 21 Dec 2023 13:43:29 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 3BLDhTkU078858; Thu, 21 Dec 2023 13:43:29 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 3BLDhTnF078855; Thu, 21 Dec 2023 13:43:29 GMT (envelope-from git) Date: Thu, 21 Dec 2023 13:43:29 GMT Message-Id: <202312211343.3BLDhTnF078855@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Olivier Certner Subject: git: 29a2d242bd1e - stable/13 - cr_canseeothergids(9): Revamp, mark as internal List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-branches@freebsd.org X-BeenThere: dev-commits-src-branches@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: olce X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 29a2d242bd1ee34443806b4478a94a915499c7de Auto-Submitted: auto-generated The branch stable/13 has been updated by olce: URL: https://cgit.FreeBSD.org/src/commit/?id=29a2d242bd1ee34443806b4478a94a915499c7de commit 29a2d242bd1ee34443806b4478a94a915499c7de Author: Olivier Certner AuthorDate: 2023-08-17 23:54:41 +0000 Commit: Olivier Certner CommitDate: 2023-12-21 13:36:48 +0000 cr_canseeothergids(9): Revamp, mark as internal Significantly clarify. Replace references to cr_canseeotheruids(9) by ones to cr_bsd_visible(9). Reviewed by: pauamma_gundo.com, mhorne Sponsored by: Kumacom SAS Differential Revision: https://reviews.freebsd.org/D40633 (cherry picked from commit 3fe9ea4d2d04d48a249b2e6161d416bb4d5b364e) Approved by: markj (mentor) --- share/man/man9/cr_canseeothergids.9 | 77 +++++++++++++++++++------------------ 1 file changed, 40 insertions(+), 37 deletions(-) diff --git a/share/man/man9/cr_canseeothergids.9 b/share/man/man9/cr_canseeothergids.9 index 79269533ae5c..f0c1e5c4e726 100644 --- a/share/man/man9/cr_canseeothergids.9 +++ b/share/man/man9/cr_canseeothergids.9 @@ -1,5 +1,6 @@ .\" .\" Copyright (c) 2003 Joseph Koshy +.\" Copyright (c) 2023 Olivier Certner .\" .\" All rights reserved. .\" @@ -25,56 +26,58 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.Dd November 11, 2003 +.Dd August 18, 2023 .Dt CR_CANSEEOTHERGIDS 9 .Os .Sh NAME .Nm cr_canseeothergids -.Nd determine visibility of objects given their group memberships +.Nd determine if subjects may see entities in a disjoint group set .Sh SYNOPSIS .Ft int .Fn cr_canseeothergids "struct ucred *u1" "struct ucred *u2" .Sh DESCRIPTION -This function determines the visibility of objects in the -kernel based on the group IDs in the credentials +.Bf -emphasis +This function is internal. +Its functionality is integrated into the function +.Xr cr_bsd_visible 9 , +which should be called instead. +.Ef +.Pp +This function checks if a subject associated to credentials .Fa u1 -and +is denied seeing a subject or object associated to credentials .Fa u2 -associated with them. +by a policy that requires both credentials to have at least one group in common. +For this determination, the effective and supplementary group IDs are used, but +not the real group IDs, as per +.Xr groupmember 9 . .Pp -The visibility of objects is influenced by the +This policy is active if and only if the .Xr sysctl 8 variable -.Va security.bsd.see_other_gids . -If this variable is non-zero then all objects in the kernel -are visible to each other irrespective of their group membership. -If this variable is zero then the object with credentials -.Fa u2 -is visible to the object with credentials -.Fa u1 -if either -.Fa u1 -is the super-user credential, or if at least one of -.Fa u1 Ns 's -group IDs is present in -.Fa u2 Ns 's -group set. -.Sh SYSCTL VARIABLES -.Bl -tag -width indent -.It Va security.bsd.see_other_gids -Must be non-zero if objects with unprivileged credentials are to be -able to see each other. -.El +.Va security.bsd.see_other_gids +is set to zero. +.Pp +As usual, the superuser (effective user ID 0) is exempt from this policy +provided that the +.Xr sysctl 8 +variable +.Va security.bsd.suser_enabled +is non-zero and no active MAC policy explicitly denies the exemption +.Po +see +.Xr priv_check_cred 9 +.Pc . .Sh RETURN VALUES -This function returns zero if the object with credential +The +.Fn cr_canseeothergids +function returns 0 if the policy is disabled, the credentials share at least one +common group, or if .Fa u1 -can -.Dq see -the object with credential -.Fa u2 , -or -.Er ESRCH -otherwise. +has privilege exempting it from the policy. +Otherwise, it returns +.Er ESRCH . .Sh SEE ALSO -.Xr cr_canseeotheruids 9 , -.Xr p_candebug 9 +.Xr cr_bsd_visible 9 , +.Xr groupmember 9 , +.Xr priv_check_cred 9