diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-10-19 19:04:47 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-10-19 19:04:47 +0200 |
commit | 3e10e879a8c334a5927d800a3663a24d562cfa31 (patch) | |
tree | 5d18bc7e38c986a044e99aa0d0a4aff4931ec7d0 /security/selinux/netlabel.c | |
parent | 98d9c66ab07471006fd7910cb16453581c41a3e7 (diff) | |
parent | 0cfd81031a26717fe14380d18275f8e217571615 (diff) |
Merge branch 'linus' into tracing-v28-for-linus-v3
Conflicts:
init/main.c
kernel/module.c
scripts/bootgraph.pl
Diffstat (limited to 'security/selinux/netlabel.c')
-rw-r--r-- | security/selinux/netlabel.c | 280 |
1 files changed, 239 insertions, 41 deletions
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c index 89b418392f1..f58701a7b72 100644 --- a/security/selinux/netlabel.c +++ b/security/selinux/netlabel.c @@ -9,7 +9,7 @@ */ /* - * (c) Copyright Hewlett-Packard Development Company, L.P., 2007 + * (c) Copyright Hewlett-Packard Development Company, L.P., 2007, 2008 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -29,8 +29,12 @@ #include <linux/spinlock.h> #include <linux/rcupdate.h> +#include <linux/ip.h> +#include <linux/ipv6.h> #include <net/sock.h> #include <net/netlabel.h> +#include <net/ip.h> +#include <net/ipv6.h> #include "objsec.h" #include "security.h" @@ -64,32 +68,69 @@ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb, } /** + * selinux_netlbl_sock_genattr - Generate the NetLabel socket secattr + * @sk: the socket + * + * Description: + * Generate the NetLabel security attributes for a socket, making full use of + * the socket's attribute cache. Returns a pointer to the security attributes + * on success, NULL on failure. + * + */ +static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk) +{ + int rc; + struct sk_security_struct *sksec = sk->sk_security; + struct netlbl_lsm_secattr *secattr; + + if (sksec->nlbl_secattr != NULL) + return sksec->nlbl_secattr; + + secattr = netlbl_secattr_alloc(GFP_ATOMIC); + if (secattr == NULL) + return NULL; + rc = security_netlbl_sid_to_secattr(sksec->sid, secattr); + if (rc != 0) { + netlbl_secattr_free(secattr); + return NULL; + } + sksec->nlbl_secattr = secattr; + + return secattr; +} + +/** * selinux_netlbl_sock_setsid - Label a socket using the NetLabel mechanism * @sk: the socket to label - * @sid: the SID to use * * Description: - * Attempt to label a socket using the NetLabel mechanism using the given - * SID. Returns zero values on success, negative values on failure. + * Attempt to label a socket using the NetLabel mechanism. Returns zero values + * on success, negative values on failure. * */ -static int selinux_netlbl_sock_setsid(struct sock *sk, u32 sid) +static int selinux_netlbl_sock_setsid(struct sock *sk) { int rc; struct sk_security_struct *sksec = sk->sk_security; - struct netlbl_lsm_secattr secattr; + struct netlbl_lsm_secattr *secattr; - netlbl_secattr_init(&secattr); + if (sksec->nlbl_state != NLBL_REQUIRE) + return 0; - rc = security_netlbl_sid_to_secattr(sid, &secattr); - if (rc != 0) - goto sock_setsid_return; - rc = netlbl_sock_setattr(sk, &secattr); - if (rc == 0) + 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; + } -sock_setsid_return: - netlbl_secattr_destroy(&secattr); return rc; } @@ -106,6 +147,38 @@ void selinux_netlbl_cache_invalidate(void) } /** + * selinux_netlbl_err - Handle a NetLabel packet error + * @skb: the packet + * @error: the error code + * @gateway: true if host is acting as a gateway, false otherwise + * + * Description: + * When a packet is dropped due to a call to avc_has_perm() pass the error + * code to the NetLabel subsystem so any protocol specific processing can be + * done. This is safe to call even if you are unsure if NetLabel labeling is + * present on the packet, NetLabel is smart enough to only act when it should. + * + */ +void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway) +{ + netlbl_skbuff_err(skb, error, gateway); +} + +/** + * selinux_netlbl_sk_security_free - Free the NetLabel fields + * @sssec: 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) +{ + if (ssec->nlbl_secattr != NULL) + netlbl_secattr_free(ssec->nlbl_secattr); +} + +/** * selinux_netlbl_sk_security_reset - Reset the NetLabel fields * @ssec: the sk_security_struct * @family: the socket family @@ -163,35 +236,118 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, } /** - * selinux_netlbl_sock_graft - Netlabel the new socket + * selinux_netlbl_skbuff_setsid - Set the NetLabel on a packet given a sid + * @skb: the packet + * @family: protocol family + * @sid: the SID + * + * Description + * Call the NetLabel mechanism to set the label of a packet using @sid. + * Returns zero on auccess, negative values on failure. + * + */ +int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, + u16 family, + u32 sid) +{ + int rc; + struct netlbl_lsm_secattr secattr_storage; + struct netlbl_lsm_secattr *secattr = NULL; + struct sock *sk; + + /* if this is a locally generated packet check to see if it is already + * being labeled by it's parent socket, if it is just exit */ + sk = skb->sk; + if (sk != NULL) { + struct sk_security_struct *sksec = sk->sk_security; + if (sksec->nlbl_state != NLBL_REQSKB) + return 0; + secattr = sksec->nlbl_secattr; + } + if (secattr == NULL) { + secattr = &secattr_storage; + netlbl_secattr_init(secattr); + rc = security_netlbl_sid_to_secattr(sid, secattr); + if (rc != 0) + goto skbuff_setsid_return; + } + + rc = netlbl_skbuff_setattr(skb, family, secattr); + +skbuff_setsid_return: + if (secattr == &secattr_storage) + netlbl_secattr_destroy(secattr); + return rc; +} + +/** + * selinux_netlbl_inet_conn_established - Netlabel the newly accepted connection * @sk: the new connection - * @sock: the new socket * * Description: - * The connection represented by @sk is being grafted onto @sock so set the - * socket's NetLabel to match the SID of @sk. + * A new connection has been established on @sk so make sure it is labeled + * correctly with the NetLabel susbsystem. * */ -void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock) +void selinux_netlbl_inet_conn_established(struct sock *sk, u16 family) { + int rc; struct sk_security_struct *sksec = sk->sk_security; - struct netlbl_lsm_secattr secattr; - u32 nlbl_peer_sid; + struct netlbl_lsm_secattr *secattr; + struct inet_sock *sk_inet = inet_sk(sk); + struct sockaddr_in addr; if (sksec->nlbl_state != NLBL_REQUIRE) return; - netlbl_secattr_init(&secattr); - if (netlbl_sock_getattr(sk, &secattr) == 0 && - secattr.flags != NETLBL_SECATTR_NONE && - security_netlbl_secattr_to_sid(&secattr, &nlbl_peer_sid) == 0) - sksec->peer_sid = nlbl_peer_sid; - netlbl_secattr_destroy(&secattr); + secattr = selinux_netlbl_sock_genattr(sk); + if (secattr == NULL) + return; - /* Try to set the NetLabel on the socket to save time later, if we fail - * here we will pick up the pieces in later calls to - * selinux_netlbl_inode_permission(). */ - selinux_netlbl_sock_setsid(sk, sksec->sid); + 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; + } } /** @@ -205,13 +361,7 @@ void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock) */ int selinux_netlbl_socket_post_create(struct socket *sock) { - struct sock *sk = sock->sk; - struct sk_security_struct *sksec = sk->sk_security; - - if (sksec->nlbl_state != NLBL_REQUIRE) - return 0; - - return selinux_netlbl_sock_setsid(sk, sksec->sid); + return selinux_netlbl_sock_setsid(sock->sk); } /** @@ -246,7 +396,7 @@ int selinux_netlbl_inode_permission(struct inode *inode, int mask) local_bh_disable(); bh_lock_sock_nested(sk); if (likely(sksec->nlbl_state == NLBL_REQUIRE)) - rc = selinux_netlbl_sock_setsid(sk, sksec->sid); + rc = selinux_netlbl_sock_setsid(sk); else rc = 0; bh_unlock_sock(sk); @@ -307,7 +457,7 @@ int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, return 0; if (nlbl_sid != SECINITSID_UNLABELED) - netlbl_skbuff_err(skb, rc); + netlbl_skbuff_err(skb, rc, 0); return rc; } @@ -334,7 +484,8 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, struct netlbl_lsm_secattr secattr; if (level == IPPROTO_IP && optname == IP_OPTIONS && - sksec->nlbl_state == NLBL_LABELED) { + (sksec->nlbl_state == NLBL_LABELED || + sksec->nlbl_state == NLBL_CONNLABELED)) { netlbl_secattr_init(&secattr); lock_sock(sk); rc = netlbl_sock_getattr(sk, &secattr); @@ -346,3 +497,50 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, return rc; } + +/** + * selinux_netlbl_socket_connect - Label a client-side socket on connect + * @sk: the socket to label + * @addr: the destination address + * + * Description: + * Attempt to label a connected socket with NetLabel using the given address. + * Returns zero values on success, negative values on failure. + * + */ +int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr) +{ + int rc; + struct sk_security_struct *sksec = sk->sk_security; + struct netlbl_lsm_secattr *secattr; + + if (sksec->nlbl_state != NLBL_REQSKB && + sksec->nlbl_state != NLBL_CONNLABELED) + return 0; + + local_bh_disable(); + bh_lock_sock_nested(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 + * the socket */ + if (addr->sa_family == AF_UNSPEC) { + netlbl_sock_delattr(sk); + sksec->nlbl_state = NLBL_REQSKB; + rc = 0; + goto socket_connect_return; + } + secattr = selinux_netlbl_sock_genattr(sk); + if (secattr == NULL) { + rc = -ENOMEM; + goto socket_connect_return; + } + rc = netlbl_conn_setattr(sk, addr, secattr); + if (rc == 0) + sksec->nlbl_state = NLBL_CONNLABELED; + +socket_connect_return: + bh_unlock_sock(sk); + local_bh_enable(); + return rc; +} |