From 3de4bab5b9f8848a0c16a4b1ffe0452f0d670237 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Fri, 17 Nov 2006 17:38:54 -0500 Subject: [PATCH] SELinux: peer secid consolidation for external network labeling Now that labeled IPsec makes use of the peer_sid field in the sk_security_struct we can remove a lot of the special cases between labeled IPsec and NetLabel. In addition, create a new function, security_skb_extlbl_sid(), which we can use in several places to get the security context of the packet's external label which allows us to further simplify the code in a few places. Signed-off-by: Paul Moore Signed-off-by: James Morris --- security/selinux/hooks.c | 43 +++------- security/selinux/include/security.h | 3 + security/selinux/include/selinux_netlabel.h | 28 +++---- security/selinux/include/xfrm.h | 5 -- security/selinux/ss/services.c | 90 +++++++-------------- security/selinux/xfrm.c | 33 -------- 6 files changed, 52 insertions(+), 150 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 975c0dfb5a11..a29d78d3f44c 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3574,27 +3574,16 @@ static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *op u32 scontext_len; struct sk_security_struct *ssec; struct inode_security_struct *isec; - u32 peer_sid = 0; + u32 peer_sid = SECSID_NULL; isec = SOCK_INODE(sock)->i_security; - /* if UNIX_STREAM check peer_sid, if TCP check dst for labelled sa */ - if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET) { + if (isec->sclass == SECCLASS_UNIX_STREAM_SOCKET || + isec->sclass == SECCLASS_TCP_SOCKET) { ssec = sock->sk->sk_security; peer_sid = ssec->peer_sid; } - else if (isec->sclass == SECCLASS_TCP_SOCKET) { - peer_sid = selinux_netlbl_socket_getpeersec_stream(sock); - if (peer_sid == SECSID_NULL) { - ssec = sock->sk->sk_security; - peer_sid = ssec->peer_sid; - } - if (peer_sid == SECSID_NULL) { - err = -ENOPROTOOPT; - goto out; - } - } - else { + if (peer_sid == SECSID_NULL) { err = -ENOPROTOOPT; goto out; } @@ -3626,13 +3615,12 @@ static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff * u32 peer_secid = SECSID_NULL; int err = 0; - if (sock && (sock->sk->sk_family == PF_UNIX)) + if (sock && sock->sk->sk_family == PF_UNIX) selinux_get_inode_sid(SOCK_INODE(sock), &peer_secid); - else if (skb) { - peer_secid = selinux_netlbl_socket_getpeersec_dgram(skb); - if (peer_secid == SECSID_NULL) - peer_secid = selinux_socket_getpeer_dgram(skb); - } + else if (skb) + security_skb_extlbl_sid(skb, + SECINITSID_UNLABELED, + &peer_secid); if (peer_secid == SECSID_NULL) err = -EINVAL; @@ -3693,17 +3681,10 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb, u32 newsid; u32 peersid; - newsid = selinux_netlbl_inet_conn_request(skb, sksec->sid); - if (newsid != SECSID_NULL) { - req->secid = newsid; - return 0; - } - - selinux_skb_xfrm_sid(skb, &peersid); - + security_skb_extlbl_sid(skb, SECINITSID_UNLABELED, &peersid); if (peersid == SECSID_NULL) { req->secid = sksec->sid; - req->peer_secid = 0; + req->peer_secid = SECSID_NULL; return 0; } @@ -3738,7 +3719,7 @@ static void selinux_inet_conn_established(struct sock *sk, { struct sk_security_struct *sksec = sk->sk_security; - selinux_skb_xfrm_sid(skb, &sksec->peer_sid); + security_skb_extlbl_sid(skb, SECINITSID_UNLABELED, &sksec->peer_sid); } static void selinux_req_classify_flow(const struct request_sock *req, diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h index 1ef79172cc8c..015f697e925f 100644 --- a/security/selinux/include/security.h +++ b/security/selinux/include/security.h @@ -8,6 +8,7 @@ #ifndef _SELINUX_SECURITY_H_ #define _SELINUX_SECURITY_H_ +#include #include "flask.h" #define SECSID_NULL 0x00000000 /* unspecified SID */ @@ -80,6 +81,8 @@ int security_netif_sid(char *name, u32 *if_sid, int security_node_sid(u16 domain, void *addr, u32 addrlen, u32 *out_sid); +void security_skb_extlbl_sid(struct sk_buff *skb, u32 base_sid, u32 *sid); + int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, u16 tclass); diff --git a/security/selinux/include/selinux_netlabel.h b/security/selinux/include/selinux_netlabel.h index 57943f4a8f90..2a732c9033e3 100644 --- a/security/selinux/include/selinux_netlabel.h +++ b/security/selinux/include/selinux_netlabel.h @@ -38,14 +38,12 @@ #ifdef CONFIG_NETLABEL void selinux_netlbl_cache_invalidate(void); +int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, u32 base_sid, u32 *sid); int selinux_netlbl_socket_post_create(struct socket *sock); void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock); -u32 selinux_netlbl_inet_conn_request(struct sk_buff *skb, u32 sock_sid); int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, struct sk_buff *skb, struct avc_audit_data *ad); -u32 selinux_netlbl_socket_getpeersec_stream(struct socket *sock); -u32 selinux_netlbl_socket_getpeersec_dgram(struct sk_buff *skb); void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec, int family); void selinux_netlbl_sk_security_init(struct sk_security_struct *ssec, @@ -62,6 +60,14 @@ static inline void selinux_netlbl_cache_invalidate(void) return; } +static inline int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, + u32 base_sid, + u32 *sid) +{ + *sid = SECSID_NULL; + return 0; +} + static inline int selinux_netlbl_socket_post_create(struct socket *sock) { return 0; @@ -73,12 +79,6 @@ static inline void selinux_netlbl_sock_graft(struct sock *sk, return; } -static inline u32 selinux_netlbl_inet_conn_request(struct sk_buff *skb, - u32 sock_sid) -{ - return SECSID_NULL; -} - static inline int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, struct sk_buff *skb, struct avc_audit_data *ad) @@ -86,16 +86,6 @@ static inline int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, return 0; } -static inline u32 selinux_netlbl_socket_getpeersec_stream(struct socket *sock) -{ - return SECSID_NULL; -} - -static inline u32 selinux_netlbl_socket_getpeersec_dgram(struct sk_buff *skb) -{ - return SECSID_NULL; -} - static inline void selinux_netlbl_sk_security_reset( struct sk_security_struct *ssec, int family) diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h index ebd7246a4be5..161eb571c82d 100644 --- a/security/selinux/include/xfrm.h +++ b/security/selinux/include/xfrm.h @@ -36,7 +36,6 @@ int selinux_xfrm_sock_rcv_skb(u32 sid, struct sk_buff *skb, struct avc_audit_data *ad); int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb, struct avc_audit_data *ad, u8 proto); -u32 selinux_socket_getpeer_dgram(struct sk_buff *skb); int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall); #else static inline int selinux_xfrm_sock_rcv_skb(u32 isec_sid, struct sk_buff *skb, @@ -51,10 +50,6 @@ static inline int selinux_xfrm_postroute_last(u32 isec_sid, struct sk_buff *skb, return 0; } -static inline int selinux_socket_getpeer_dgram(struct sk_buff *skb) -{ - return SECSID_NULL; -} static inline int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall) { *sid = SECSID_NULL; diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index b66b454fe72b..b43dd803fd5e 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -54,6 +54,7 @@ #include "mls.h" #include "objsec.h" #include "selinux_netlabel.h" +#include "xfrm.h" extern void selnl_notify_policyload(u32 seqno); unsigned int policydb_loaded_version; @@ -2191,6 +2192,32 @@ void selinux_audit_set_callback(int (*callback)(void)) aurule_callback = callback; } +/** + * security_skb_extlbl_sid - Determine the external label of a packet + * @skb: the packet + * @base_sid: the SELinux SID to use as a context for MLS only external labels + * @sid: the packet's SID + * + * Description: + * Check the various different forms of external packet labeling and determine + * the external SID for the packet. + * + */ +void security_skb_extlbl_sid(struct sk_buff *skb, u32 base_sid, u32 *sid) +{ + u32 xfrm_sid; + u32 nlbl_sid; + + selinux_skb_xfrm_sid(skb, &xfrm_sid); + if (selinux_netlbl_skbuff_getsid(skb, + (xfrm_sid == SECSID_NULL ? + base_sid : xfrm_sid), + &nlbl_sid) != 0) + nlbl_sid = SECSID_NULL; + + *sid = (nlbl_sid == SECSID_NULL ? xfrm_sid : nlbl_sid); +} + #ifdef CONFIG_NETLABEL /* * This is the structure we store inside the NetLabel cache block. @@ -2408,9 +2435,7 @@ netlbl_secattr_to_sid_return_cleanup: * assign to the packet. Returns zero on success, negative values on failure. * */ -static int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, - u32 base_sid, - u32 *sid) +int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, u32 base_sid, u32 *sid) { int rc; struct netlbl_lsm_secattr secattr; @@ -2615,29 +2640,6 @@ void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock) rcu_read_unlock(); } -/** - * selinux_netlbl_inet_conn_request - Handle a new connection request - * @skb: the packet - * @sock_sid: the SID of the parent socket - * - * Description: - * If present, use the security attributes of the packet in @skb and the - * parent sock's SID to arrive at a SID for the new child sock. Returns the - * SID of the connection or SECSID_NULL on failure. - * - */ -u32 selinux_netlbl_inet_conn_request(struct sk_buff *skb, u32 sock_sid) -{ - int rc; - u32 peer_sid; - - rc = selinux_netlbl_skbuff_getsid(skb, sock_sid, &peer_sid); - if (rc != 0) - return SECSID_NULL; - - return peer_sid; -} - /** * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled * @inode: the file descriptor's inode @@ -2727,42 +2729,6 @@ int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, return rc; } -/** - * selinux_netlbl_socket_getpeersec_stream - Return the connected peer's SID - * @sock: the socket - * - * Description: - * Examine @sock to find the connected peer's SID. Returns the SID on success - * or SECSID_NULL on error. - * - */ -u32 selinux_netlbl_socket_getpeersec_stream(struct socket *sock) -{ - struct sk_security_struct *sksec = sock->sk->sk_security; - return sksec->peer_sid; -} - -/** - * selinux_netlbl_socket_getpeersec_dgram - Return the SID of a NetLabel packet - * @skb: the packet - * - * Description: - * Examine @skb to find the SID assigned to it by NetLabel. Returns the SID on - * success, SECSID_NULL on error. - * - */ -u32 selinux_netlbl_socket_getpeersec_dgram(struct sk_buff *skb) -{ - int peer_sid; - - if (selinux_netlbl_skbuff_getsid(skb, - SECINITSID_UNLABELED, - &peer_sid) != 0) - return SECSID_NULL; - - return peer_sid; -} - /** * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel * @sock: the socket diff --git a/security/selinux/xfrm.c b/security/selinux/xfrm.c index 9b777140068f..bd8d1ef40a90 100644 --- a/security/selinux/xfrm.c +++ b/security/selinux/xfrm.c @@ -372,39 +372,6 @@ void selinux_xfrm_state_free(struct xfrm_state *x) kfree(ctx); } -/* - * SELinux internal function to retrieve the context of a UDP packet - * based on its security association. - * - * Retrieve via setsockopt IP_PASSSEC and recvmsg with control message - * type SCM_SECURITY. - */ -u32 selinux_socket_getpeer_dgram(struct sk_buff *skb) -{ - struct sec_path *sp; - - if (skb == NULL) - return SECSID_NULL; - - if (skb->sk->sk_protocol != IPPROTO_UDP) - return SECSID_NULL; - - sp = skb->sp; - if (sp) { - int i; - - for (i = sp->len-1; i >= 0; i--) { - struct xfrm_state *x = sp->xvec[i]; - if (selinux_authorizable_xfrm(x)) { - struct xfrm_sec_ctx *ctx = x->security; - return ctx->ctx_sid; - } - } - } - - return SECSID_NULL; -} - /* * LSM hook implementation that authorizes deletion of labeled SAs. */ -- 2.30.2