From nobody Fri Dec 19 08:07:11 2025 Received: from smtp-bc0c.mail.infomaniak.ch (smtp-bc0c.mail.infomaniak.ch [45.157.188.12]) (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 216C91F03DB for ; Fri, 31 Jan 2025 16:31:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.157.188.12 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738341105; cv=none; b=Dd9cRJhPg5VvBD5Pa9wzNeq0lI8jaKHcsmcgckmmeE+R4WB/cfXURC96pDI5kCxFqpavCd9CiLijwgAtDuzYosLF9TLLLTTFl7xuBknw3ytn6LXyDSuenzqQZAQnyCxbhZ78dv8FM5h/JXVqpR2lalIBwecYAQ8mtnyV3zO8RcU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738341105; c=relaxed/simple; bh=brwtFa0YPuxT8obx9if/Rd1hfPfqP49c4g+GRIMs9+8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=IEXtYLtNGNHKswFZNBnRwVdIwxUBF4vw/54unJ1JCMSr/iFPo6UZaBjcQ2BDz9rP7Jxk/nZ8ZlpeNGT7hHjPQBaFnYEHHrFbAuWLOYhMqsYzd4Kssok/j5ndxecXRkcb1yDIy30T2CxYoF3yJwXZ2QHn2f6HjEaPB5Cbv8UnPvk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net; spf=pass smtp.mailfrom=digikod.net; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b=pIHlQmxW; arc=none smtp.client-ip=45.157.188.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=digikod.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=digikod.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=digikod.net header.i=@digikod.net header.b="pIHlQmxW" Received: from smtp-3-0000.mail.infomaniak.ch (smtp-3-0000.mail.infomaniak.ch [10.4.36.107]) by smtp-3-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4Yl1cY25VtzQpW; Fri, 31 Jan 2025 17:31:41 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digikod.net; s=20191114; t=1738341101; bh=S6/k9lM0kMYCCuiR8eF0rMjss9IyPVc9vBRzSQGM+EM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pIHlQmxWSc4F2EfN35ThkZQtAPXyalKk3VP5GEAuw0kJQ2o4PoeUBVSopIXkKcFPh Evi3lFVbNS2w8fVugEomAjoLAcy+7tVr/I6eHBEqcuUwdAyLxd9nY5VlQKjRMr9xvy n5PrZ5DkZTb3j38ygCa6IO9tWOFa5FYuTA1h/INA= Received: from unknown by smtp-3-0000.mail.infomaniak.ch (Postfix) with ESMTPA id 4Yl1cX3SFrzdf9; Fri, 31 Jan 2025 17:31:40 +0100 (CET) From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= To: Eric Paris , Paul Moore , =?UTF-8?q?G=C3=BCnther=20Noack?= , "Serge E . Hallyn" Cc: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Ben Scarlato , Casey Schaufler , Charles Zaffery , Daniel Burgener , Francis Laniel , James Morris , Jann Horn , Jeff Xu , Jorge Lucangeli Obes , Kees Cook , Konstantin Meskhidze , Matt Bobrowski , Mikhail Ivanov , Phil Sutter , Praveen K Paladugu , Robert Salvet , Shervin Oloumi , Song Liu , Tahera Fahimi , Tyler Hicks , audit@vger.kernel.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH v5 14/24] landlock: Log TCP bind and connect denials Date: Fri, 31 Jan 2025 17:30:49 +0100 Message-ID: <20250131163059.1139617-15-mic@digikod.net> In-Reply-To: <20250131163059.1139617-1-mic@digikod.net> References: <20250131163059.1139617-1-mic@digikod.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Infomaniak-Routing: alpha Add audit support to socket_bind and socket_connect hooks. The related blockers are: - net.bind_tcp - net.connect_tcp Audit event sample: type=3DLANDLOCK_DENY msg=3Daudit(1729738800.349:44): domain=3D195ba459b b= lockers=3Dnet.connect_tcp daddr=3D127.0.0.1 dest=3D80 Cc: G=C3=BCnther Noack Cc: Konstantin Meskhidze Cc: Mikhail Ivanov Signed-off-by: Micka=C3=ABl Sala=C3=BCn Link: https://lore.kernel.org/r/20250131163059.1139617-15-mic@digikod.net --- Changes since v4: - Rebase on top of the landlock_log_denial() and subject type changes. Changes since v3: - Rename blockers from net_* to net.* Changes since v2: - Remove potentially superfluous IPv6 saddr log, spotted by Francis Laniel. - Cosmetic improvements. --- security/landlock/audit.c | 12 +++++++++ security/landlock/audit.h | 1 + security/landlock/net.c | 51 ++++++++++++++++++++++++++++++++++++--- 3 files changed, 60 insertions(+), 4 deletions(-) diff --git a/security/landlock/audit.c b/security/landlock/audit.c index 194c99fac133..9c856b31f9f6 100644 --- a/security/landlock/audit.c +++ b/security/landlock/audit.c @@ -42,6 +42,13 @@ static const char *const fs_access_strings[] =3D { =20 static_assert(ARRAY_SIZE(fs_access_strings) =3D=3D LANDLOCK_NUM_ACCESS_FS); =20 +static const char *const net_access_strings[] =3D { + [BIT_INDEX(LANDLOCK_ACCESS_NET_BIND_TCP)] =3D "net.bind_tcp", + [BIT_INDEX(LANDLOCK_ACCESS_NET_CONNECT_TCP)] =3D "net.connect_tcp", +}; + +static_assert(ARRAY_SIZE(net_access_strings) =3D=3D LANDLOCK_NUM_ACCESS_NE= T); + static __attribute_const__ const char * get_blocker(const enum landlock_request_type type, const unsigned long access_bit) @@ -59,6 +66,11 @@ get_blocker(const enum landlock_request_type type, if (WARN_ON_ONCE(access_bit >=3D ARRAY_SIZE(fs_access_strings))) return "unknown"; return fs_access_strings[access_bit]; + + case LANDLOCK_REQUEST_NET_ACCESS: + if (WARN_ON_ONCE(access_bit >=3D ARRAY_SIZE(net_access_strings))) + return "unknown"; + return net_access_strings[access_bit]; } =20 WARN_ON_ONCE(1); diff --git a/security/landlock/audit.h b/security/landlock/audit.h index 6765a419001d..eeff2c5bfa4f 100644 --- a/security/landlock/audit.h +++ b/security/landlock/audit.h @@ -19,6 +19,7 @@ enum landlock_request_type { LANDLOCK_REQUEST_PTRACE =3D 1, LANDLOCK_REQUEST_FS_CHANGE_LAYOUT, LANDLOCK_REQUEST_FS_ACCESS, + LANDLOCK_REQUEST_NET_ACCESS, }; =20 /* diff --git a/security/landlock/net.c b/security/landlock/net.c index 53dc9d94a5c2..a8e94562f2b1 100644 --- a/security/landlock/net.c +++ b/security/landlock/net.c @@ -7,10 +7,12 @@ */ =20 #include +#include #include #include #include =20 +#include "audit.h" #include "common.h" #include "cred.h" #include "limits.h" @@ -55,6 +57,10 @@ static int current_check_access_socket(struct socket *co= nst sock, }; const struct landlock_cred_security *const subject =3D landlock_get_applicable_subject(current_cred(), masks, NULL); + struct lsm_network_audit audit_net =3D {}; + struct landlock_request request =3D { + .type =3D LANDLOCK_REQUEST_NET_ACCESS, + }; =20 if (!subject) return 0; @@ -69,18 +75,48 @@ static int current_check_access_socket(struct socket *c= onst sock, =20 switch (address->sa_family) { case AF_UNSPEC: - case AF_INET: + case AF_INET: { + const struct sockaddr_in *addr4; + if (addrlen < sizeof(struct sockaddr_in)) return -EINVAL; - port =3D ((struct sockaddr_in *)address)->sin_port; + + addr4 =3D (struct sockaddr_in *)address; + port =3D addr4->sin_port; + + if (access_request =3D=3D LANDLOCK_ACCESS_NET_CONNECT_TCP) { + audit_net.dport =3D port; + audit_net.v4info.daddr =3D addr4->sin_addr.s_addr; + } else if (access_request =3D=3D LANDLOCK_ACCESS_NET_BIND_TCP) { + audit_net.sport =3D port; + audit_net.v4info.saddr =3D addr4->sin_addr.s_addr; + } else { + WARN_ON_ONCE(1); + } break; + } =20 #if IS_ENABLED(CONFIG_IPV6) - case AF_INET6: + case AF_INET6: { + const struct sockaddr_in6 *addr6; + if (addrlen < SIN6_LEN_RFC2133) return -EINVAL; - port =3D ((struct sockaddr_in6 *)address)->sin6_port; + + addr6 =3D (struct sockaddr_in6 *)address; + port =3D addr6->sin6_port; + + if (access_request =3D=3D LANDLOCK_ACCESS_NET_CONNECT_TCP) { + audit_net.dport =3D port; + audit_net.v6info.daddr =3D addr6->sin6_addr; + } else if (access_request =3D=3D LANDLOCK_ACCESS_NET_BIND_TCP) { + audit_net.sport =3D port; + audit_net.v6info.saddr =3D addr6->sin6_addr; + } else { + WARN_ON_ONCE(1); + } break; + } #endif /* IS_ENABLED(CONFIG_IPV6) */ =20 default: @@ -150,6 +186,13 @@ static int current_check_access_socket(struct socket *= const sock, ARRAY_SIZE(layer_masks))) return 0; =20 + audit_net.family =3D address->sa_family; + request.audit.type =3D LSM_AUDIT_DATA_NET; + request.audit.u.net =3D &audit_net; + request.access =3D access_request; + request.layer_masks =3D &layer_masks; + request.layer_masks_size =3D ARRAY_SIZE(layer_masks); + landlock_log_denial(subject, &request); return -EACCES; } =20 --=20 2.48.1