From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 038A32582 for ; Wed, 29 Mar 2023 14:08:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F16BC4339B; Wed, 29 Mar 2023 14:08:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680098906; bh=1Qdhg7zDnhDkQZ2AI5pqIT98OGUbEhzHGMs0Fr/TNZs=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Hes5yzeSDQgXJo4jDv52u9/fqRYcg+dgcR0TUiHphUW5znrOHNcygs9veHb4OKIDx xNm1BGO3eWukNE71KxPTNYRXRyKvgLwqdxqwSYyvOdM5gkx8aNy65EYtmdMgNiuuO/ X9C9ozS1nWtt1bJHw9qnH9jqVCRUYAWRUXmMLp6B3oi32HsMYNsH89JcbshpMhSISj YkGYXVV53SgSlbWKP/r9n6tX+WkmRdso6gWpye/NPFddljDmO1jzGhR3Y8OvSh42IG LfvBwjwMlsI86gsy/RaBooigdqymYVo238qUOHJVOs2ZUVsjJAItSbc3TdRazBbQYV YoKRVTm61YDRg== Subject: [PATCH v2 3/4] exports(5): Describe the xprtsec= export option From: Chuck Lever To: SteveD@redhat.com Cc: linux-nfs@vger.kernel.org, rick.macklem@gmail.com, kernel-tls-handshake@lists.linux.dev Date: Wed, 29 Mar 2023 10:08:25 -0400 Message-ID: <168009890542.2522.10109556599153238262.stgit@manet.1015granger.net> In-Reply-To: <168009806320.2522.10415374334827613451.stgit@manet.1015granger.net> References: <168009806320.2522.10415374334827613451.stgit@manet.1015granger.net> User-Agent: StGit/1.5 Precedence: bulk X-Mailing-List: kernel-tls-handshake@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit From: Chuck Lever Cc: Rick Macklem Signed-off-by: Chuck Lever --- utils/exportfs/exports.man | 51 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) diff --git a/utils/exportfs/exports.man b/utils/exportfs/exports.man index 54b3f8776ea6..83dd6807c570 100644 --- a/utils/exportfs/exports.man +++ b/utils/exportfs/exports.man @@ -125,7 +125,55 @@ In that case you may include multiple sec= options, and following options will be enforced only for access using flavors listed in the immediately preceding sec= option. The only options that are permitted to vary in this way are ro, rw, no_root_squash, root_squash, and all_squash. +.SS Transport layer security +The Linux NFS server allows the use of RPC-with-TLS (RFC 9289) to +protect RPC traffic between itself and its clients. +Alternately, administrators can secure NFS traffic using a VPN, +or an ssh tunnel or similar mechanism, in a way that is transparent +to the server. .PP +To enable the use of RPC-with-TLS, the server's administrator must +install and configure +.BR tlshd +to handle transport layer security handshake requests from the local +kernel. +Clients can then choose to use RPC-with-TLS or they may continue +operating without it. +.PP +Administrators may require the use of RPC-with-TLS to protect access +to individual exports. +This is particularly useful when using non-cryptographic security +flavors such as +.IR sec=sys . +The +.I xprtsec= +option, followed by an unordered colon-delimited list of security policies, +can restrict access to the export to only clients that have negotiated +transport-layer security. +Currently supported transport layer security policies include: +.TP +.IR none +The server permits clients to access the export +without the use of transport layer security. +.TP +.IR tls +The server permits clients that have negotiated an RPC-with-TLS session +without peer authentication (confidentiality only) to access the export. +Clients are not required to offer an x.509 certificate +when establishing a transport layer security session. +.TP +.IR mtls +The server permits clients that have negotiated an RPC-with-TLS session +with peer authentication to access the export. +The server requires clients to offer an x.509 certificate +when establishing a transport layer security session. +.PP +If RPC-with-TLS is configured and enabled and the +.I xprtsec= +option is not specified, the default setting for an export is +.IR xprtsec=none:tls:mtls . +With this setting, the server permits clients to use any transport +layer security mechanism or none at all to access the export. .SS General Options .BR exportfs understands the following export options: @@ -581,7 +629,8 @@ a character class wildcard match. .BR netgroup (5), .BR mountd (8), .BR nfsd (8), -.BR showmount (8). +.BR showmount (8), +.BR tlshd (8). .\".SH DIAGNOSTICS .\"An error parsing the file is reported using syslogd(8) as level NOTICE from .\"a DAEMON whenever