diff options
Diffstat (limited to 'security/selinux/netlabel.c')
| -rw-r--r-- | security/selinux/netlabel.c | 223 |
1 files changed, 87 insertions, 136 deletions
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c index f58701a7b72..0364120d1ec 100644 --- a/security/selinux/netlabel.c +++ b/security/selinux/netlabel.c @@ -4,7 +4,7 @@ * This file provides the necessary glue to tie NetLabel into the SELinux * subsystem. * - * Author: Paul Moore <paul.moore@hp.com> + * Author: Paul Moore <paul@paul-moore.com> * */ @@ -29,6 +29,7 @@ #include <linux/spinlock.h> #include <linux/rcupdate.h> +#include <linux/gfp.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <net/sock.h> @@ -100,38 +101,29 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk) } /** - * selinux_netlbl_sock_setsid - Label a socket using the NetLabel mechanism - * @sk: the socket to label + * selinux_netlbl_sock_getattr - Get the cached NetLabel secattr + * @sk: the socket + * @sid: the SID * - * Description: - * Attempt to label a socket using the NetLabel mechanism. Returns zero values - * on success, negative values on failure. + * Query the socket's cached secattr and if the SID matches the cached value + * return the cache, otherwise return NULL. * */ -static int selinux_netlbl_sock_setsid(struct sock *sk) +static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr( + const struct sock *sk, + u32 sid) { - int rc; struct sk_security_struct *sksec = sk->sk_security; - struct netlbl_lsm_secattr *secattr; - - if (sksec->nlbl_state != NLBL_REQUIRE) - return 0; + struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr; - secattr = selinux_netlbl_sock_genattr(sk); if (secattr == NULL) - return -ENOMEM; - rc = netlbl_sock_setattr(sk, secattr); - switch (rc) { - case 0: - sksec->nlbl_state = NLBL_LABELED; - break; - case -EDESTADDRREQ: - sksec->nlbl_state = NLBL_REQSKB; - rc = 0; - break; - } + return NULL; - return rc; + if ((secattr->flags & NETLBL_SECATTR_SECID) && + (secattr->attr.secid == sid)) + return secattr; + + return NULL; } /** @@ -166,35 +158,31 @@ void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway) /** * selinux_netlbl_sk_security_free - Free the NetLabel fields - * @sssec: the sk_security_struct + * @sksec: the sk_security_struct * * Description: * Free all of the memory in the NetLabel fields of a sk_security_struct. * */ -void selinux_netlbl_sk_security_free(struct sk_security_struct *ssec) +void selinux_netlbl_sk_security_free(struct sk_security_struct *sksec) { - if (ssec->nlbl_secattr != NULL) - netlbl_secattr_free(ssec->nlbl_secattr); + if (sksec->nlbl_secattr != NULL) + netlbl_secattr_free(sksec->nlbl_secattr); } /** * selinux_netlbl_sk_security_reset - Reset the NetLabel fields - * @ssec: the sk_security_struct + * @sksec: the sk_security_struct * @family: the socket family * * Description: * Called when the NetLabel state of a sk_security_struct needs to be reset. - * The caller is responsibile for all the NetLabel sk_security_struct locking. + * The caller is responsible for all the NetLabel sk_security_struct locking. * */ -void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec, - int family) +void selinux_netlbl_sk_security_reset(struct sk_security_struct *sksec) { - if (family == PF_INET) - ssec->nlbl_state = NLBL_REQUIRE; - else - ssec->nlbl_state = NLBL_UNSET; + sksec->nlbl_state = NLBL_UNSET; } /** @@ -243,7 +231,7 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, * * Description * Call the NetLabel mechanism to set the label of a packet using @sid. - * Returns zero on auccess, negative values on failure. + * Returns zero on success, negative values on failure. * */ int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, @@ -262,7 +250,7 @@ int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, struct sk_security_struct *sksec = sk->sk_security; if (sksec->nlbl_state != NLBL_REQSKB) return 0; - secattr = sksec->nlbl_secattr; + secattr = selinux_netlbl_sock_getattr(sk, sid); } if (secattr == NULL) { secattr = &secattr_storage; @@ -281,126 +269,86 @@ skbuff_setsid_return: } /** - * selinux_netlbl_inet_conn_established - Netlabel the newly accepted connection - * @sk: the new connection + * selinux_netlbl_inet_conn_request - Label an incoming stream connection + * @req: incoming connection request socket * * Description: - * A new connection has been established on @sk so make sure it is labeled - * correctly with the NetLabel susbsystem. + * A new incoming connection request is represented by @req, we need to label + * the new request_sock here and the stack will ensure the on-the-wire label + * will get preserved when a full sock is created once the connection handshake + * is complete. Returns zero on success, negative values on failure. * */ -void selinux_netlbl_inet_conn_established(struct sock *sk, u16 family) +int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family) { int rc; - struct sk_security_struct *sksec = sk->sk_security; - struct netlbl_lsm_secattr *secattr; - struct inet_sock *sk_inet = inet_sk(sk); - struct sockaddr_in addr; - - if (sksec->nlbl_state != NLBL_REQUIRE) - return; + struct netlbl_lsm_secattr secattr; - secattr = selinux_netlbl_sock_genattr(sk); - if (secattr == NULL) - return; + if (family != PF_INET) + return 0; - rc = netlbl_sock_setattr(sk, secattr); - switch (rc) { - case 0: - sksec->nlbl_state = NLBL_LABELED; - break; - case -EDESTADDRREQ: - /* no PF_INET6 support yet because we don't support any IPv6 - * labeling protocols */ - if (family != PF_INET) { - sksec->nlbl_state = NLBL_UNSET; - return; - } - - addr.sin_family = family; - addr.sin_addr.s_addr = sk_inet->daddr; - if (netlbl_conn_setattr(sk, (struct sockaddr *)&addr, - secattr) != 0) { - /* we failed to label the connected socket (could be - * for a variety of reasons, the actual "why" isn't - * important here) so we have to go to our backup plan, - * labeling the packets individually in the netfilter - * local output hook. this is okay but we need to - * adjust the MSS of the connection to take into - * account any labeling overhead, since we don't know - * the exact overhead at this point we'll use the worst - * case value which is 40 bytes for IPv4 */ - struct inet_connection_sock *sk_conn = inet_csk(sk); - sk_conn->icsk_ext_hdr_len += 40 - - (sk_inet->opt ? sk_inet->opt->optlen : 0); - sk_conn->icsk_sync_mss(sk, sk_conn->icsk_pmtu_cookie); - - sksec->nlbl_state = NLBL_REQSKB; - } else - sksec->nlbl_state = NLBL_CONNLABELED; - break; - default: - /* note that we are failing to label the socket which could be - * a bad thing since it means traffic could leave the system - * without the desired labeling, however, all is not lost as - * we have a check in selinux_netlbl_inode_permission() to - * pick up the pieces that we might drop here because we can't - * return an error code */ - break; - } + netlbl_secattr_init(&secattr); + rc = security_netlbl_sid_to_secattr(req->secid, &secattr); + if (rc != 0) + goto inet_conn_request_return; + rc = netlbl_req_setattr(req, &secattr); +inet_conn_request_return: + netlbl_secattr_destroy(&secattr); + return rc; } /** - * selinux_netlbl_socket_post_create - Label a socket using NetLabel - * @sock: the socket to label + * selinux_netlbl_inet_csk_clone - Initialize the newly created sock + * @sk: the new sock * * Description: - * Attempt to label a socket using the NetLabel mechanism using the given - * SID. Returns zero values on success, negative values on failure. + * A new connection has been established using @sk, we've already labeled the + * socket via the request_sock struct in selinux_netlbl_inet_conn_request() but + * we need to set the NetLabel state here since we now have a sock structure. * */ -int selinux_netlbl_socket_post_create(struct socket *sock) +void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family) { - return selinux_netlbl_sock_setsid(sock->sk); + struct sk_security_struct *sksec = sk->sk_security; + + if (family == PF_INET) + sksec->nlbl_state = NLBL_LABELED; + else + sksec->nlbl_state = NLBL_UNSET; } /** - * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled - * @inode: the file descriptor's inode - * @mask: the permission mask + * selinux_netlbl_socket_post_create - Label a socket using NetLabel + * @sock: the socket to label + * @family: protocol family * * Description: - * Looks at a file's inode and if it is marked as a socket protected by - * NetLabel then verify that the socket has been labeled, if not try to label - * the socket now with the inode's SID. Returns zero on success, negative - * values on failure. + * Attempt to label a socket using the NetLabel mechanism using the given + * SID. Returns zero values on success, negative values on failure. * */ -int selinux_netlbl_inode_permission(struct inode *inode, int mask) +int selinux_netlbl_socket_post_create(struct sock *sk, u16 family) { int rc; - struct sock *sk; - struct socket *sock; - struct sk_security_struct *sksec; - - if (!S_ISSOCK(inode->i_mode) || - ((mask & (MAY_WRITE | MAY_APPEND)) == 0)) - return 0; + struct sk_security_struct *sksec = sk->sk_security; + struct netlbl_lsm_secattr *secattr; - sock = SOCKET_I(inode); - sk = sock->sk; - sksec = sk->sk_security; - if (sksec->nlbl_state != NLBL_REQUIRE) + if (family != PF_INET) return 0; - local_bh_disable(); - bh_lock_sock_nested(sk); - if (likely(sksec->nlbl_state == NLBL_REQUIRE)) - rc = selinux_netlbl_sock_setsid(sk); - else + secattr = selinux_netlbl_sock_genattr(sk); + if (secattr == NULL) + return -ENOMEM; + rc = netlbl_sock_setattr(sk, family, secattr); + switch (rc) { + case 0: + sksec->nlbl_state = NLBL_LABELED; + break; + case -EDESTADDRREQ: + sksec->nlbl_state = NLBL_REQSKB; rc = 0; - bh_unlock_sock(sk); - local_bh_enable(); + break; + } return rc; } @@ -421,7 +369,7 @@ int selinux_netlbl_inode_permission(struct inode *inode, int mask) int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, struct sk_buff *skb, u16 family, - struct avc_audit_data *ad) + struct common_audit_data *ad) { int rc; u32 nlbl_sid; @@ -488,10 +436,15 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, sksec->nlbl_state == NLBL_CONNLABELED)) { netlbl_secattr_init(&secattr); lock_sock(sk); + /* call the netlabel function directly as we want to see the + * on-the-wire label that is assigned via the socket's options + * and not the cached netlabel/lsm attributes */ rc = netlbl_sock_getattr(sk, &secattr); release_sock(sk); - if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE) + if (rc == 0) rc = -EACCES; + else if (rc == -ENOMSG) + rc = 0; netlbl_secattr_destroy(&secattr); } @@ -518,8 +471,7 @@ int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr) sksec->nlbl_state != NLBL_CONNLABELED) return 0; - local_bh_disable(); - bh_lock_sock_nested(sk); + lock_sock(sk); /* connected sockets are allowed to disconnect when the address family * is set to AF_UNSPEC, if that is what is happening we want to reset @@ -540,7 +492,6 @@ int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr) sksec->nlbl_state = NLBL_CONNLABELED; socket_connect_return: - bh_unlock_sock(sk); - local_bh_enable(); + release_sock(sk); return rc; } |
