All of lore.kernel.org
 help / color / mirror / Atom feed
From: Richard Haines <richard_c_haines@btinternet.com>
To: selinux@tycho.nsa.gov, netdev@vger.kernel.org,
	linux-sctp@vger.kernel.org,
	linux-security-module@vger.kernel.org
Cc: paul@paul-moore.com, vyasevich@gmail.com, nhorman@tuxdriver.com,
	sds@tycho.nsa.gov, eparis@parisplace.org,
	marcelo.leitner@gmail.com,
	Richard Haines <richard_c_haines@btinternet.com>
Subject: [RFC PATCH 3/5] sctp: Add LSM hooks
Date: Tue, 17 Oct 2017 14:58:33 +0100	[thread overview]
Message-ID: <20171017135833.4292-1-richard_c_haines@btinternet.com> (raw)

Add security hooks to allow security modules to exercise access control
over SCTP.

Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
---
 include/net/sctp/structs.h | 10 ++++++++
 include/uapi/linux/sctp.h  |  1 +
 net/sctp/sm_make_chunk.c   | 12 +++++++++
 net/sctp/sm_statefuns.c    | 14 ++++++++++-
 net/sctp/socket.c          | 61 +++++++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 96 insertions(+), 2 deletions(-)

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 7767577..6e72e3e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1270,6 +1270,16 @@ struct sctp_endpoint {
 	      reconf_enable:1;
 
 	__u8  strreset_enable;
+
+	/* Security identifiers from incoming (INIT). These are set by
+	 * security_sctp_assoc_request(). These will only be used by
+	 * SCTP TCP type sockets and peeled off connections as they
+	 * cause a new socket to be generated. security_sctp_sk_clone()
+	 * will then plug these into the new socket.
+	 */
+
+	u32 secid;
+	u32 peer_secid;
 };
 
 /* Recover the outter endpoint structure. */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index 6217ff8..c04812f 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -122,6 +122,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_RESET_ASSOC	120
 #define SCTP_ADD_STREAMS	121
 #define SCTP_SOCKOPT_PEELOFF_FLAGS 122
+#define SCTP_SENDMSG_CONNECT	123
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 6110447..ca4705b 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3059,6 +3059,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr, &asconf->source, sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_ADD_IP,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		/* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
 		 * request and does not have the local resources to add this
 		 * new address to the association, it MUST return an Error
@@ -3125,6 +3131,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_SET_PRIMARY,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		peer = sctp_assoc_lookup_paddr(asoc, &addr);
 		if (!peer)
 			return SCTP_ERROR_DNS_FAILED;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index b2a74c3..4ba5805 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -314,6 +314,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	sctp_unrecognized_param_t *unk_param;
 	int len;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	/* 6.10 Bundling
 	 * An endpoint MUST NOT bundle INIT, INIT ACK or
 	 * SHUTDOWN COMPLETE with any other chunks.
@@ -446,7 +451,6 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	}
 
 	sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
-
 	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
 
 	/*
@@ -507,6 +511,11 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(struct net *net,
 	struct sctp_chunk *err_chunk;
 	struct sctp_packet *packet;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT_ACK))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	if (!sctp_vtag_verify(chunk, asoc))
 		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
 
@@ -899,6 +908,9 @@ sctp_disposition_t sctp_sf_do_5_1E_ca(struct net *net,
 	 */
 	sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
 
+	/* Set peer label for connection. */
+	security_inet_conn_established(ep->base.sk, chunk->skb);
+
 	/* RFC 2960 5.1 Normal Establishment of an Association
 	 *
 	 * E) Upon reception of the COOKIE ACK, endpoint "A" will move
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 70355a0..e948163 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1014,6 +1014,12 @@ static int sctp_setsockopt_bindx(struct sock *sk,
 	/* Do the work. */
 	switch (op) {
 	case SCTP_BINDX_ADD_ADDR:
+		/* Allow security module to validate bindx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD,
+						 (struct sockaddr *)kaddrs,
+						 addrs_size);
+		if (err)
+			goto out;
 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
 		if (err)
 			goto out;
@@ -1223,6 +1229,7 @@ static int __sctp_connect(struct sock *sk,
 
 	if (assoc_id)
 		*assoc_id = asoc->assoc_id;
+
 	err = sctp_wait_for_connect(asoc, &timeo);
 	/* Note: the asoc may be freed after the return of
 	 * sctp_wait_for_connect.
@@ -1336,9 +1343,17 @@ static int __sctp_setsockopt_connectx(struct sock *sk,
 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
 		err = -EFAULT;
 	} else {
+		/* Allow security module to validate connectx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
+						 (struct sockaddr *)kaddrs,
+						  addrs_size);
+		if (err)
+			goto out_free;
+
 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
 	}
 
+out_free:
 	kfree(kaddrs);
 
 	return err;
@@ -1604,6 +1619,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 	struct sctp_transport *transport, *chunk_tp;
 	struct sctp_chunk *chunk;
 	union sctp_addr to;
+	struct sctp_af *af;
 	struct sockaddr *msg_name = NULL;
 	struct sctp_sndrcvinfo default_sinfo;
 	struct sctp_sndrcvinfo *sinfo;
@@ -1833,6 +1849,24 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 		}
 
 		scope = sctp_scope(&to);
+
+		/* Label connection socket for first association 1-to-many
+		 * style for client sequence socket()->sendmsg(). This
+		 * needs to be done before sctp_assoc_add_peer() as that will
+		 * set up the initial packet that needs to account for any
+		 * security ip options (CIPSO/CALIPSO) added to the packet.
+		 */
+		af = sctp_get_af_specific(to.sa.sa_family);
+		if (!af) {
+			err = -EINVAL;
+			goto out_unlock;
+		}
+		err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT,
+						 (struct sockaddr *)&to,
+						 af->sockaddr_len);
+		if (err < 0)
+			goto out_unlock;
+
 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
 		if (!new_asoc) {
 			err = -ENOMEM;
@@ -2865,6 +2899,8 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 {
 	struct sctp_prim prim;
 	struct sctp_transport *trans;
+	struct sctp_af *af;
+	int err;
 
 	if (optlen != sizeof(struct sctp_prim))
 		return -EINVAL;
@@ -2872,6 +2908,17 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
 		return -EFAULT;
 
+	/* Allow security module to validate address but need address len. */
+	af = sctp_get_af_specific(prim.ssp_addr.ss_family);
+	if (!af)
+		return -EINVAL;
+
+	err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.ssp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
 	if (!trans)
 		return -EINVAL;
@@ -3192,6 +3239,13 @@ static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optva
 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
 		return -EADDRNOTAVAIL;
 
+	/* Allow security module to validate address. */
+	err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.sspp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
 	chunk = sctp_make_asconf_set_prim(asoc,
 					  (union sctp_addr *)&prim.sspp_addr);
@@ -8024,6 +8078,8 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 {
 	struct inet_sock *inet = inet_sk(sk);
 	struct inet_sock *newinet;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
 
 	newsk->sk_type = sk->sk_type;
 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
@@ -8066,7 +8122,10 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
 		net_enable_timestamp();
 
-	security_sk_clone(sk, newsk);
+	/* Set newsk security attributes from orginal sk and connection
+	 * security attribute from ep.
+	 */
+	security_sctp_sk_clone(ep, sk, newsk);
 }
 
 static inline void sctp_copy_descendant(struct sock *sk_to,
-- 
2.13.6

WARNING: multiple messages have this Message-ID (diff)
From: Richard Haines <richard_c_haines@btinternet.com>
To: linux-security-module@vger.kernel.org
Subject: [RFC PATCH 3/5] sctp: Add LSM hooks
Date: Tue, 17 Oct 2017 13:58:33 +0000	[thread overview]
Message-ID: <20171017135833.4292-1-richard_c_haines@btinternet.com> (raw)

Add security hooks to allow security modules to exercise access control
over SCTP.

Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
---
 include/net/sctp/structs.h | 10 ++++++++
 include/uapi/linux/sctp.h  |  1 +
 net/sctp/sm_make_chunk.c   | 12 +++++++++
 net/sctp/sm_statefuns.c    | 14 ++++++++++-
 net/sctp/socket.c          | 61 +++++++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 96 insertions(+), 2 deletions(-)

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 7767577..6e72e3e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1270,6 +1270,16 @@ struct sctp_endpoint {
 	      reconf_enable:1;
 
 	__u8  strreset_enable;
+
+	/* Security identifiers from incoming (INIT). These are set by
+	 * security_sctp_assoc_request(). These will only be used by
+	 * SCTP TCP type sockets and peeled off connections as they
+	 * cause a new socket to be generated. security_sctp_sk_clone()
+	 * will then plug these into the new socket.
+	 */
+
+	u32 secid;
+	u32 peer_secid;
 };
 
 /* Recover the outter endpoint structure. */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index 6217ff8..c04812f 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -122,6 +122,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_RESET_ASSOC	120
 #define SCTP_ADD_STREAMS	121
 #define SCTP_SOCKOPT_PEELOFF_FLAGS 122
+#define SCTP_SENDMSG_CONNECT	123
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 6110447..ca4705b 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3059,6 +3059,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr, &asconf->source, sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_ADD_IP,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		/* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
 		 * request and does not have the local resources to add this
 		 * new address to the association, it MUST return an Error
@@ -3125,6 +3131,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_SET_PRIMARY,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		peer = sctp_assoc_lookup_paddr(asoc, &addr);
 		if (!peer)
 			return SCTP_ERROR_DNS_FAILED;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index b2a74c3..4ba5805 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -314,6 +314,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	sctp_unrecognized_param_t *unk_param;
 	int len;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	/* 6.10 Bundling
 	 * An endpoint MUST NOT bundle INIT, INIT ACK or
 	 * SHUTDOWN COMPLETE with any other chunks.
@@ -446,7 +451,6 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	}
 
 	sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
-
 	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
 
 	/*
@@ -507,6 +511,11 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(struct net *net,
 	struct sctp_chunk *err_chunk;
 	struct sctp_packet *packet;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT_ACK))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	if (!sctp_vtag_verify(chunk, asoc))
 		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
 
@@ -899,6 +908,9 @@ sctp_disposition_t sctp_sf_do_5_1E_ca(struct net *net,
 	 */
 	sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
 
+	/* Set peer label for connection. */
+	security_inet_conn_established(ep->base.sk, chunk->skb);
+
 	/* RFC 2960 5.1 Normal Establishment of an Association
 	 *
 	 * E) Upon reception of the COOKIE ACK, endpoint "A" will move
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 70355a0..e948163 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1014,6 +1014,12 @@ static int sctp_setsockopt_bindx(struct sock *sk,
 	/* Do the work. */
 	switch (op) {
 	case SCTP_BINDX_ADD_ADDR:
+		/* Allow security module to validate bindx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD,
+						 (struct sockaddr *)kaddrs,
+						 addrs_size);
+		if (err)
+			goto out;
 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
 		if (err)
 			goto out;
@@ -1223,6 +1229,7 @@ static int __sctp_connect(struct sock *sk,
 
 	if (assoc_id)
 		*assoc_id = asoc->assoc_id;
+
 	err = sctp_wait_for_connect(asoc, &timeo);
 	/* Note: the asoc may be freed after the return of
 	 * sctp_wait_for_connect.
@@ -1336,9 +1343,17 @@ static int __sctp_setsockopt_connectx(struct sock *sk,
 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
 		err = -EFAULT;
 	} else {
+		/* Allow security module to validate connectx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
+						 (struct sockaddr *)kaddrs,
+						  addrs_size);
+		if (err)
+			goto out_free;
+
 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
 	}
 
+out_free:
 	kfree(kaddrs);
 
 	return err;
@@ -1604,6 +1619,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 	struct sctp_transport *transport, *chunk_tp;
 	struct sctp_chunk *chunk;
 	union sctp_addr to;
+	struct sctp_af *af;
 	struct sockaddr *msg_name = NULL;
 	struct sctp_sndrcvinfo default_sinfo;
 	struct sctp_sndrcvinfo *sinfo;
@@ -1833,6 +1849,24 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 		}
 
 		scope = sctp_scope(&to);
+
+		/* Label connection socket for first association 1-to-many
+		 * style for client sequence socket()->sendmsg(). This
+		 * needs to be done before sctp_assoc_add_peer() as that will
+		 * set up the initial packet that needs to account for any
+		 * security ip options (CIPSO/CALIPSO) added to the packet.
+		 */
+		af = sctp_get_af_specific(to.sa.sa_family);
+		if (!af) {
+			err = -EINVAL;
+			goto out_unlock;
+		}
+		err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT,
+						 (struct sockaddr *)&to,
+						 af->sockaddr_len);
+		if (err < 0)
+			goto out_unlock;
+
 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
 		if (!new_asoc) {
 			err = -ENOMEM;
@@ -2865,6 +2899,8 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 {
 	struct sctp_prim prim;
 	struct sctp_transport *trans;
+	struct sctp_af *af;
+	int err;
 
 	if (optlen != sizeof(struct sctp_prim))
 		return -EINVAL;
@@ -2872,6 +2908,17 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
 		return -EFAULT;
 
+	/* Allow security module to validate address but need address len. */
+	af = sctp_get_af_specific(prim.ssp_addr.ss_family);
+	if (!af)
+		return -EINVAL;
+
+	err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.ssp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
 	if (!trans)
 		return -EINVAL;
@@ -3192,6 +3239,13 @@ static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optva
 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
 		return -EADDRNOTAVAIL;
 
+	/* Allow security module to validate address. */
+	err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.sspp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
 	chunk = sctp_make_asconf_set_prim(asoc,
 					  (union sctp_addr *)&prim.sspp_addr);
@@ -8024,6 +8078,8 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 {
 	struct inet_sock *inet = inet_sk(sk);
 	struct inet_sock *newinet;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
 
 	newsk->sk_type = sk->sk_type;
 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
@@ -8066,7 +8122,10 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
 		net_enable_timestamp();
 
-	security_sk_clone(sk, newsk);
+	/* Set newsk security attributes from orginal sk and connection
+	 * security attribute from ep.
+	 */
+	security_sctp_sk_clone(ep, sk, newsk);
 }
 
 static inline void sctp_copy_descendant(struct sock *sk_to,
-- 
2.13.6


WARNING: multiple messages have this Message-ID (diff)
From: richard_c_haines@btinternet.com (Richard Haines)
To: linux-security-module@vger.kernel.org
Subject: [RFC PATCH 3/5] sctp: Add LSM hooks
Date: Tue, 17 Oct 2017 14:58:33 +0100	[thread overview]
Message-ID: <20171017135833.4292-1-richard_c_haines@btinternet.com> (raw)

Add security hooks to allow security modules to exercise access control
over SCTP.

Signed-off-by: Richard Haines <richard_c_haines@btinternet.com>
---
 include/net/sctp/structs.h | 10 ++++++++
 include/uapi/linux/sctp.h  |  1 +
 net/sctp/sm_make_chunk.c   | 12 +++++++++
 net/sctp/sm_statefuns.c    | 14 ++++++++++-
 net/sctp/socket.c          | 61 +++++++++++++++++++++++++++++++++++++++++++++-
 5 files changed, 96 insertions(+), 2 deletions(-)

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 7767577..6e72e3e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1270,6 +1270,16 @@ struct sctp_endpoint {
 	      reconf_enable:1;
 
 	__u8  strreset_enable;
+
+	/* Security identifiers from incoming (INIT). These are set by
+	 * security_sctp_assoc_request(). These will only be used by
+	 * SCTP TCP type sockets and peeled off connections as they
+	 * cause a new socket to be generated. security_sctp_sk_clone()
+	 * will then plug these into the new socket.
+	 */
+
+	u32 secid;
+	u32 peer_secid;
 };
 
 /* Recover the outter endpoint structure. */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index 6217ff8..c04812f 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -122,6 +122,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_RESET_ASSOC	120
 #define SCTP_ADD_STREAMS	121
 #define SCTP_SOCKOPT_PEELOFF_FLAGS 122
+#define SCTP_SENDMSG_CONNECT	123
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 6110447..ca4705b 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3059,6 +3059,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr, &asconf->source, sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_ADD_IP,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		/* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
 		 * request and does not have the local resources to add this
 		 * new address to the association, it MUST return an Error
@@ -3125,6 +3131,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
 		if (af->is_any(&addr))
 			memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
 
+		if (security_sctp_bind_connect(asoc->ep->base.sk,
+					       SCTP_PARAM_SET_PRIMARY,
+					       (struct sockaddr *)&addr,
+					       af->sockaddr_len))
+			return SCTP_ERROR_REQ_REFUSED;
+
 		peer = sctp_assoc_lookup_paddr(asoc, &addr);
 		if (!peer)
 			return SCTP_ERROR_DNS_FAILED;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index b2a74c3..4ba5805 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -314,6 +314,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	sctp_unrecognized_param_t *unk_param;
 	int len;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	/* 6.10 Bundling
 	 * An endpoint MUST NOT bundle INIT, INIT ACK or
 	 * SHUTDOWN COMPLETE with any other chunks.
@@ -446,7 +451,6 @@ sctp_disposition_t sctp_sf_do_5_1B_init(struct net *net,
 	}
 
 	sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
-
 	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
 
 	/*
@@ -507,6 +511,11 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(struct net *net,
 	struct sctp_chunk *err_chunk;
 	struct sctp_packet *packet;
 
+	/* Update socket peer label if first association. */
+	if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+					chunk->skb, SCTP_CID_INIT_ACK))
+		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
 	if (!sctp_vtag_verify(chunk, asoc))
 		return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
 
@@ -899,6 +908,9 @@ sctp_disposition_t sctp_sf_do_5_1E_ca(struct net *net,
 	 */
 	sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
 
+	/* Set peer label for connection. */
+	security_inet_conn_established(ep->base.sk, chunk->skb);
+
 	/* RFC 2960 5.1 Normal Establishment of an Association
 	 *
 	 * E) Upon reception of the COOKIE ACK, endpoint "A" will move
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 70355a0..e948163 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1014,6 +1014,12 @@ static int sctp_setsockopt_bindx(struct sock *sk,
 	/* Do the work. */
 	switch (op) {
 	case SCTP_BINDX_ADD_ADDR:
+		/* Allow security module to validate bindx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD,
+						 (struct sockaddr *)kaddrs,
+						 addrs_size);
+		if (err)
+			goto out;
 		err = sctp_bindx_add(sk, kaddrs, addrcnt);
 		if (err)
 			goto out;
@@ -1223,6 +1229,7 @@ static int __sctp_connect(struct sock *sk,
 
 	if (assoc_id)
 		*assoc_id = asoc->assoc_id;
+
 	err = sctp_wait_for_connect(asoc, &timeo);
 	/* Note: the asoc may be freed after the return of
 	 * sctp_wait_for_connect.
@@ -1336,9 +1343,17 @@ static int __sctp_setsockopt_connectx(struct sock *sk,
 	if (__copy_from_user(kaddrs, addrs, addrs_size)) {
 		err = -EFAULT;
 	} else {
+		/* Allow security module to validate connectx addresses. */
+		err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
+						 (struct sockaddr *)kaddrs,
+						  addrs_size);
+		if (err)
+			goto out_free;
+
 		err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
 	}
 
+out_free:
 	kfree(kaddrs);
 
 	return err;
@@ -1604,6 +1619,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 	struct sctp_transport *transport, *chunk_tp;
 	struct sctp_chunk *chunk;
 	union sctp_addr to;
+	struct sctp_af *af;
 	struct sockaddr *msg_name = NULL;
 	struct sctp_sndrcvinfo default_sinfo;
 	struct sctp_sndrcvinfo *sinfo;
@@ -1833,6 +1849,24 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 		}
 
 		scope = sctp_scope(&to);
+
+		/* Label connection socket for first association 1-to-many
+		 * style for client sequence socket()->sendmsg(). This
+		 * needs to be done before sctp_assoc_add_peer() as that will
+		 * set up the initial packet that needs to account for any
+		 * security ip options (CIPSO/CALIPSO) added to the packet.
+		 */
+		af = sctp_get_af_specific(to.sa.sa_family);
+		if (!af) {
+			err = -EINVAL;
+			goto out_unlock;
+		}
+		err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT,
+						 (struct sockaddr *)&to,
+						 af->sockaddr_len);
+		if (err < 0)
+			goto out_unlock;
+
 		new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
 		if (!new_asoc) {
 			err = -ENOMEM;
@@ -2865,6 +2899,8 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 {
 	struct sctp_prim prim;
 	struct sctp_transport *trans;
+	struct sctp_af *af;
+	int err;
 
 	if (optlen != sizeof(struct sctp_prim))
 		return -EINVAL;
@@ -2872,6 +2908,17 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
 	if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
 		return -EFAULT;
 
+	/* Allow security module to validate address but need address len. */
+	af = sctp_get_af_specific(prim.ssp_addr.ss_family);
+	if (!af)
+		return -EINVAL;
+
+	err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.ssp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
 	if (!trans)
 		return -EINVAL;
@@ -3192,6 +3239,13 @@ static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optva
 	if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
 		return -EADDRNOTAVAIL;
 
+	/* Allow security module to validate address. */
+	err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR,
+					 (struct sockaddr *)&prim.sspp_addr,
+					 af->sockaddr_len);
+	if (err)
+		return err;
+
 	/* Create an ASCONF chunk with SET_PRIMARY parameter	*/
 	chunk = sctp_make_asconf_set_prim(asoc,
 					  (union sctp_addr *)&prim.sspp_addr);
@@ -8024,6 +8078,8 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 {
 	struct inet_sock *inet = inet_sk(sk);
 	struct inet_sock *newinet;
+	struct sctp_sock *sp = sctp_sk(sk);
+	struct sctp_endpoint *ep = sp->ep;
 
 	newsk->sk_type = sk->sk_type;
 	newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
@@ -8066,7 +8122,10 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
 	if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
 		net_enable_timestamp();
 
-	security_sk_clone(sk, newsk);
+	/* Set newsk security attributes from orginal sk and connection
+	 * security attribute from ep.
+	 */
+	security_sctp_sk_clone(ep, sk, newsk);
 }
 
 static inline void sctp_copy_descendant(struct sock *sk_to,
-- 
2.13.6

--
To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

             reply	other threads:[~2017-10-17 14:01 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-17 13:58 Richard Haines [this message]
2017-10-17 13:58 ` [RFC PATCH 3/5] sctp: Add LSM hooks Richard Haines
2017-10-17 13:58 ` Richard Haines
2017-10-18 15:05 ` Xin Long
2017-10-18 15:05   ` Xin Long
2017-10-18 15:05   ` Xin Long
2017-10-20 11:16   ` Neil Horman
2017-10-20 11:16     ` Neil Horman
2017-10-20 11:16     ` Neil Horman
2017-10-20 12:04     ` Richard Haines
2017-10-20 12:04       ` Richard Haines
2017-10-20 12:04       ` Richard Haines
2017-10-20 13:14       ` Xin Long
2017-10-20 13:14         ` Xin Long
2017-10-20 13:14         ` Xin Long
2017-10-24 20:27         ` Richard Haines
2017-10-24 20:27           ` Richard Haines
2017-10-24 20:27           ` Richard Haines

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20171017135833.4292-1-richard_c_haines@btinternet.com \
    --to=richard_c_haines@btinternet.com \
    --cc=eparis@parisplace.org \
    --cc=linux-sctp@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=marcelo.leitner@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=nhorman@tuxdriver.com \
    --cc=paul@paul-moore.com \
    --cc=sds@tycho.nsa.gov \
    --cc=selinux@tycho.nsa.gov \
    --cc=vyasevich@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.