From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f74.google.com (mail-ej1-f74.google.com [209.85.218.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6D6E11990C5 for ; Fri, 24 Jan 2025 16:37:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737736672; cv=none; b=YhqEvFXmlGNQzipD8zst6sb4hQYAp5NUbOFlDThcbT/4kV7BsFdctlcCLeku6Vwdxxes04jat9NhJVFP/k3epQ+twN3EarNi/biDO99SZtSPsgV0co083JyzxlT2vYrhXzvzjoVQcOE8LmRRNEaFkUGDhcn2MLo3fGm9ByGqyzo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737736672; c=relaxed/simple; bh=j6USTa6pm15px+wXhvEW4Bihhlh4P/An65yi+KMFLTo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ouJL0k/tHKY4JIQIBXjAtloniai2cwWVrJdyKlzuN8sE0fCnxsxeyhU0LD65ntZBmyIg0zLVg8b42m8SrFxD9XWs34iqifHmpKDV+FLIPb6Imz8Lm8NDu/pWFizWU4+pFqX1ZUNzEUCOXJS93WiG23abRFIOLwjv89j7yMZ+rmE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--gnoack.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=obaZjFub; arc=none smtp.client-ip=209.85.218.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--gnoack.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="obaZjFub" Received: by mail-ej1-f74.google.com with SMTP id a640c23a62f3a-aa67f03ca86so189369366b.2 for ; Fri, 24 Jan 2025 08:37:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1737736669; x=1738341469; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=mRSlSYjWIHgZvKVgeVYAoe/yruh6HvLc215c9xsjuX0=; b=obaZjFubj+ow8hbuG/cBXpXz0iPPsK5DQbTi72hlDo+T1lsNeUer0ya3edxSoZnCug H38ezupfXFShhxDx8LUCvghtGw11zxjQUj63njMK4oHikJ1Q+5OUr65CdMslWkZfddeB Gbq3dsRQMsnezFkxzo+fdTfSV8bSKphaSClkWr2bkPPpRpDfsSLJmDpjon2SFNDkUdDI t/4/Mt0QYLx9TuvTXDcBVgYxD9+ZypFkXxomi+KTZ89hYhE8bJYfdVutMi9hr3yRaC/D meVh8Nrlz37QS8CTnxu1SQEgqr+nar4M7BdLHgfDSpX17PlgcGhtc/leEUlnIgQnfY/L /7CA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737736669; x=1738341469; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=mRSlSYjWIHgZvKVgeVYAoe/yruh6HvLc215c9xsjuX0=; b=mgsiQ1EnZ6VwTKQZ9RFCa4MlXNgbmljySs/4fBlgYahBw7yHXIs9WA41v4F8ciiH3G KKibbgdnntz0dMI8jJZ3PXYbSJRrBkyQlSj6ylL1N1lkW1dky1lO2JQHPut0Wy8yQ6Oq Gs4Y2l4Em10pj7gH+F8QAlFhxpIIuEkeZvjdeujFktR4LUfnnZ3CvDBNoRURpiV3c77m q+vWqBCDlFmC6hvRlR33znIhbmYT5Aac4cABWj1u1H0Age0KOEjZtdDU3ukHZ85kL2Lq XkBnlgd5FbL5fduzR5gBTjzS5sKr1sol0JDVOkQQ6WGxcIU4Kg7Wr/pgLObqqZoUUgFH Suxg== X-Gm-Message-State: AOJu0YysMprDHd30XfqQVFuGoROAV+1FO5XYwYhxBVdzErjZhGvdHN5w 7S1vWZ7v9YjyV/6PsYDtU0g1sYh7wo0r1yiFCOMhifVR7hxLqw9wPXto71ZarcZgnRpF1ZC1fFV 6xQ== X-Google-Smtp-Source: AGHT+IEEC928SpjHB/WwoDmkptV3MMx0uk1XIs6iD2/VYfn4srfIx8ZY+zlS566BIzZ1ihuBgQkIX8IUtMk= X-Received: from edbio6.prod.google.com ([2002:a05:6402:2186:b0:5d9:87fb:9151]) (user=gnoack job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:34ca:b0:5d0:81f5:a398 with SMTP id 4fb4d7f45d1cf-5db7d2dc58bmr66839625a12.1.1737736668781; Fri, 24 Jan 2025 08:37:48 -0800 (PST) Date: Fri, 24 Jan 2025 16:37:09 +0000 In-Reply-To: <20250124154445.162841-1-gnoack@google.com> Precedence: bulk X-Mailing-List: linux-man@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250124154445.162841-1-gnoack@google.com> X-Mailer: git-send-email 2.48.1.262.g85cc9f2d1e-goog Message-ID: <20250124163709.168805-3-gnoack@google.com> Subject: [PATCH man 2/3] landlock.7: Move over documentation for ABI version 6 From: "=?UTF-8?q?G=C3=BCnther=20Noack?=" To: Alejandro Colomar Cc: linux-man@vger.kernel.org, linux-security-module@vger.kernel.org, "=?UTF-8?q?G=C3=BCnther=20Noack?=" , "=?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?=" , Tahera Fahimi , Tanya Agarwal Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable With this ABI version, Landlock can restrict outgoing interactions with higher-privileged Landlock domains through Abstract Unix Domain sockets and signals. Cc: Micka=C3=ABl Sala=C3=BCn Cc: Tahera Fahimi Cc: Tanya Agarwal Signed-off-by: G=C3=BCnther Noack --- man/man7/landlock.7 | 69 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 68 insertions(+), 1 deletion(-) diff --git a/man/man7/landlock.7 b/man/man7/landlock.7 index 11f76b072..30dbac73d 100644 --- a/man/man7/landlock.7 +++ b/man/man7/landlock.7 @@ -248,7 +248,8 @@ This access right is available since the fifth version = of the Landlock ABI. .SS Network flags These flags enable to restrict a sandboxed process to a set of network actions. -This is supported since the Landlock ABI version 4. +.P +This is supported since Landlock ABI version 4. .P The following access rights apply to TCP port numbers: .TP @@ -258,6 +259,24 @@ Bind a TCP socket to a local port. .B LANDLOCK_ACCESS_NET_CONNECT_TCP Connect an active TCP socket to a remote port. .\" +.SS Scope flags +These flags enable to isolate a sandboxed process from a set of IPC action= s. +Setting a flag for a ruleset will isolate the Landlock domain +to forbid connections to resources outside the domain. +.P +This is supported since Landlock ABI version 6. +.P +The following scopes exist: +.TP +.B LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET +Restrict a sandboxed process from connecting to an abstract UNIX socket +created by a process outside the related Landlock domain +(e.g., a parent domain or a non-sandboxed process). +.TP +.B LANDLOCK_SCOPE_SIGNAL +Restrict a sandboxed process from sending a signal +to another process outside the domain. +.\" .SS Layers of file path access rights Each time a thread enforces a ruleset on itself, it updates its Landlock domain with a new layer of policy. @@ -334,6 +353,51 @@ and related syscalls on a target process, a sandboxed process should have a subset of the target process rules, which means the tracee must be in a sub-domain of the tracer. .\" +.SS IPC scoping +Similar to the implicit +.BR "Ptrace restrictions" , +we may want to further restrict interactions between sandboxes. +Each Landlock domain can be explicitly scoped for a set of actions +by specifying it on a ruleset. +For example, if a sandboxed process should not be able to +.BR connect (2) +to a non-sandboxed process through abstract +.BR unix (7) +sockets, +we can specify such a restriction with +.BR LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET . +Moreover, if a sandboxed process should not be able +to send a signal to a non-sandboxed process, +we can specify this restriction with +.BR LANDLOCK_SCOPE_SIGNAL . +.P +A sandboxed process can connect to a non-sandboxed process +when its domain is not scoped. +If a process's domain is scoped, +it can only connect to sockets created by processes in the same scope. +Moreover, +If a process is scoped to send signal to a non-scoped process, +it can only send signals to processes in the same scope. +.P +A connected datagram socket behaves like a stream socket +when its domain is scoped, +meaning if the domain is scoped after the socket is connected, +it can still +.BR send (2) +data just like a stream socket. +However, in the same scenario, +a non-connected datagram socket cannot send data (with +.BR sendto (2)) +outside its scope. +.P +A process with a scoped domain can inherit a socket +created by a non-scoped process. +The process cannot connect to this socket since it has a scoped domain. +.P +IPC scoping does not support exceptions, so if a domain is scoped, +no rules can be added to allow access to resources or processes +outside of the scope. +.\" .SS Truncating files The operations covered by .B LANDLOCK_ACCESS_FS_WRITE_FILE @@ -413,6 +477,9 @@ _ _ _ \^ \^ LANDLOCK_ACCESS_NET_CONNECT_TCP _ _ _ 5 6.10 LANDLOCK_ACCESS_FS_IOCTL_DEV +_ _ _ +6 6.12 LANDLOCK_SCOPE_ABSTRACT_UNIX_SOCKET +\^ \^ LANDLOCK_SCOPE_SIGNAL .TE .P Users should use the Landlock ABI version rather than the kernel version --=20 2.48.1.262.g85cc9f2d1e-goog