From nobody Fri Dec 19 19:19:33 2025 Received: from smtp-190b.mail.infomaniak.ch (smtp-190b.mail.infomaniak.ch [185.125.25.11]) (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 21AFA201031 for ; Wed, 8 Jan 2025 15:44:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.125.25.11 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736351055; cv=none; b=i4Z1/ZRMpQqIUiDMZ+0oJxkkNJ2Y9aONtYaJQv0vuJWZUO4lsb8rw9BWtnMZSpftgjZCwRsTYhTr8EUb+XnMl+4XaInqHr1jJUYAPP+GwX4HmqTdg2bXsTwOAAWi8CKoBC0/jvcVJGZOO6j60JsBuviYbQGiwt9yaNr2L3Ey1Ek= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736351055; c=relaxed/simple; bh=dNF9revyAHdaReGII1otboacnCMyx6THKc+/K3qcWn8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=EGY84dTiIcoZM2yOanM5ISHlgptOyxlk20S0aibJwlUfFCVRxpUH20H/NMx85mLuXg+g5m1bjzJLm9ltcBK9ZoOy7U/K9Vquq0k4fNPaG4kYSHgqhOYmIhfX8jEG4on8JmJklLkFg+iyi/3BWb0HNQYhZGgLMdDXf46o2qDXEdU= 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=fr5Dh3T1; arc=none smtp.client-ip=185.125.25.11 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="fr5Dh3T1" Received: from smtp-4-0000.mail.infomaniak.ch (smtp-4-0000.mail.infomaniak.ch [10.7.10.107]) by smtp-4-3000.mail.infomaniak.ch (Postfix) with ESMTPS id 4YSsfL4146zrYM; Wed, 8 Jan 2025 16:44:10 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=digikod.net; s=20191114; t=1736351050; bh=urI9rHx8OZzAhZ+lkRE6eb+dDcOP0tlB9XFr0Wi2DSc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fr5Dh3T1y5iLXLhJ2sPAis+FhvApVylseUXfAd0NvFehpLiD/qcOsigEgNUSnmuHF g6PBnV4ZHtfBAF1nrbqsOnliGzrK9TedLzubet727F5H5wxb9IUG0pVVsrjQtbdUDT 4G2UDliQ57kg6FXDVlAB84TLsLoxMNjas63XW7VM= Received: from unknown by smtp-4-0000.mail.infomaniak.ch (Postfix) with ESMTPA id 4YSsfK5YPsz2yw; Wed, 8 Jan 2025 16:44:09 +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 v4 16/30] landlock: Log TCP bind and connect denials Date: Wed, 8 Jan 2025 16:43:24 +0100 Message-ID: <20250108154338.1129069-17-mic@digikod.net> In-Reply-To: <20250108154338.1129069-1-mic@digikod.net> References: <20250108154338.1129069-1-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/20250108154338.1129069-17-mic@digikod.net --- 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 89446e913d9f..2744e3d4fe73 100644 --- a/security/landlock/audit.c +++ b/security/landlock/audit.c @@ -41,6 +41,13 @@ 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) @@ -58,6 +65,11 @@ 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 762cdbd10b3a..9a3697b901b5 100644 --- a/security/landlock/audit.h +++ b/security/landlock/audit.h @@ -18,6 +18,7 @@ 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 d5dcc4407a19..45c80fa417c4 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" @@ -57,6 +59,10 @@ static int current_check_access_socket(struct socket *co= nst sock, const struct landlock_ruleset *const dom =3D landlock_get_applicable_domain(landlock_get_current_domain(), any_net); + struct lsm_network_audit audit_net =3D {}; + struct landlock_request request =3D { + .type =3D LANDLOCK_REQUEST_NET_ACCESS, + }; =20 if (!dom) return 0; @@ -73,18 +79,48 @@ 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: @@ -153,6 +189,13 @@ 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(dom, &request); return -EACCES; } =20 --=20 2.47.1