diff options
Diffstat (limited to 'security/selinux/netlabel.c')
| -rw-r--r-- | security/selinux/netlabel.c | 271 |
1 files changed, 210 insertions, 61 deletions
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c index da4b8b233280..d51dfe892312 100644 --- a/security/selinux/netlabel.c +++ b/security/selinux/netlabel.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * SELinux NetLabel Support * @@ -5,26 +6,10 @@ * subsystem. * * Author: Paul Moore <paul@paul-moore.com> - * */ /* * (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 - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See - * the GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * */ #include <linux/spinlock.h> @@ -32,6 +17,7 @@ #include <linux/gfp.h> #include <linux/ip.h> #include <linux/ipv6.h> +#include <linux/lsm_hooks.h> #include <net/sock.h> #include <net/netlabel.h> #include <net/ip.h> @@ -44,6 +30,7 @@ /** * selinux_netlbl_sidlookup_cached - Cache a SID lookup * @skb: the packet + * @family: the packet's address family * @secattr: the NetLabel security attributes * @sid: the SID * @@ -54,6 +41,7 @@ * */ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb, + u16 family, struct netlbl_lsm_secattr *secattr, u32 *sid) { @@ -63,7 +51,7 @@ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb, if (rc == 0 && (secattr->flags & NETLBL_SECATTR_CACHEABLE) && (secattr->flags & NETLBL_SECATTR_CACHE)) - netlbl_cache_add(skb, secattr); + netlbl_cache_add(skb, family, secattr); return rc; } @@ -75,13 +63,13 @@ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb, * 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. + * on success, or an ERR_PTR 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 sk_security_struct *sksec = selinux_sock(sk); struct netlbl_lsm_secattr *secattr; if (sksec->nlbl_secattr != NULL) @@ -89,11 +77,12 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk) secattr = netlbl_secattr_alloc(GFP_ATOMIC); if (secattr == NULL) - return NULL; + return ERR_PTR(-ENOMEM); + rc = security_netlbl_sid_to_secattr(sksec->sid, secattr); if (rc != 0) { netlbl_secattr_free(secattr); - return NULL; + return ERR_PTR(rc); } sksec->nlbl_secattr = secattr; @@ -101,6 +90,32 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk) } /** + * selinux_netlbl_sock_getattr - Get the cached NetLabel secattr + * @sk: the socket + * @sid: the SID + * + * Query the socket's cached secattr and if the SID matches the cached value + * return the cache, otherwise return NULL. + * + */ +static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr( + const struct sock *sk, + u32 sid) +{ + struct sk_security_struct *sksec = selinux_sock(sk); + struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr; + + if (secattr == NULL) + return NULL; + + if ((secattr->flags & NETLBL_SECATTR_SECID) && + (secattr->attr.secid == sid)) + return secattr; + + return NULL; +} + +/** * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache * * Description: @@ -115,6 +130,7 @@ void selinux_netlbl_cache_invalidate(void) /** * selinux_netlbl_err - Handle a NetLabel packet error * @skb: the packet + * @family: the packet's address family * @error: the error code * @gateway: true if host is acting as a gateway, false otherwise * @@ -125,9 +141,9 @@ void selinux_netlbl_cache_invalidate(void) * 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) +void selinux_netlbl_err(struct sk_buff *skb, u16 family, int error, int gateway) { - netlbl_skbuff_err(skb, error, gateway); + netlbl_skbuff_err(skb, family, error, gateway); } /** @@ -140,14 +156,17 @@ void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway) */ void selinux_netlbl_sk_security_free(struct sk_security_struct *sksec) { - if (sksec->nlbl_secattr != NULL) - netlbl_secattr_free(sksec->nlbl_secattr); + if (!sksec->nlbl_secattr) + return; + + netlbl_secattr_free(sksec->nlbl_secattr); + sksec->nlbl_secattr = NULL; + sksec->nlbl_state = NLBL_UNSET; } /** * selinux_netlbl_sk_security_reset - Reset the NetLabel fields * @sksec: the sk_security_struct - * @family: the socket family * * Description: * Called when the NetLabel state of a sk_security_struct needs to be reset. @@ -181,6 +200,7 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, struct netlbl_lsm_secattr secattr; if (!netlbl_enabled()) { + *type = NETLBL_NLTYPE_NONE; *sid = SECSID_NULL; return 0; } @@ -188,7 +208,8 @@ int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, netlbl_secattr_init(&secattr); rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE) - rc = selinux_netlbl_sidlookup_cached(skb, &secattr, sid); + rc = selinux_netlbl_sidlookup_cached(skb, family, + &secattr, sid); else *sid = SECSID_NULL; *type = secattr.type; @@ -219,12 +240,13 @@ int selinux_netlbl_skbuff_setsid(struct sk_buff *skb, /* 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; + sk = skb_to_full_sk(skb); if (sk != NULL) { - struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *sksec = selinux_sock(sk); + 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; @@ -243,8 +265,60 @@ skbuff_setsid_return: } /** + * selinux_netlbl_sctp_assoc_request - Label an incoming sctp association. + * @asoc: incoming association. + * @skb: the packet. + * + * Description: + * A new incoming connection is represented by @asoc, ...... + * Returns zero on success, negative values on failure. + * + */ +int selinux_netlbl_sctp_assoc_request(struct sctp_association *asoc, + struct sk_buff *skb) +{ + int rc; + struct netlbl_lsm_secattr secattr; + struct sk_security_struct *sksec = selinux_sock(asoc->base.sk); + struct sockaddr_in addr4; + struct sockaddr_in6 addr6; + + if (asoc->base.sk->sk_family != PF_INET && + asoc->base.sk->sk_family != PF_INET6) + return 0; + + netlbl_secattr_init(&secattr); + rc = security_netlbl_sid_to_secattr(asoc->secid, &secattr); + if (rc != 0) + goto assoc_request_return; + + /* Move skb hdr address info to a struct sockaddr and then call + * netlbl_conn_setattr(). + */ + if (ip_hdr(skb)->version == 4) { + addr4.sin_family = AF_INET; + addr4.sin_addr.s_addr = ip_hdr(skb)->saddr; + rc = netlbl_conn_setattr(asoc->base.sk, (void *)&addr4, &secattr); + } else if (IS_ENABLED(CONFIG_IPV6) && ip_hdr(skb)->version == 6) { + addr6.sin6_family = AF_INET6; + addr6.sin6_addr = ipv6_hdr(skb)->saddr; + rc = netlbl_conn_setattr(asoc->base.sk, (void *)&addr6, &secattr); + } else { + rc = -EAFNOSUPPORT; + } + + if (rc == 0) + sksec->nlbl_state = NLBL_LABELED; + +assoc_request_return: + netlbl_secattr_destroy(&secattr); + return rc; +} + +/** * selinux_netlbl_inet_conn_request - Label an incoming stream connection * @req: incoming connection request socket + * @family: the request socket's address family * * Description: * A new incoming connection request is represented by @req, we need to label @@ -258,7 +332,7 @@ int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family) int rc; struct netlbl_lsm_secattr secattr; - if (family != PF_INET) + if (family != PF_INET && family != PF_INET6) return 0; netlbl_secattr_init(&secattr); @@ -274,6 +348,7 @@ inet_conn_request_return: /** * selinux_netlbl_inet_csk_clone - Initialize the newly created sock * @sk: the new sock + * @family: the sock's address family * * Description: * A new connection has been established using @sk, we've already labeled the @@ -283,17 +358,33 @@ inet_conn_request_return: */ void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family) { - struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *sksec = selinux_sock(sk); - if (family == PF_INET) + if (family == PF_INET || family == PF_INET6) sksec->nlbl_state = NLBL_LABELED; else sksec->nlbl_state = NLBL_UNSET; } /** + * selinux_netlbl_sctp_sk_clone - Copy state to the newly created sock + * @sk: current sock + * @newsk: the new sock + * + * Description: + * Called whenever a new socket is created by accept(2) or sctp_peeloff(3). + */ +void selinux_netlbl_sctp_sk_clone(struct sock *sk, struct sock *newsk) +{ + struct sk_security_struct *sksec = selinux_sock(sk); + struct sk_security_struct *newsksec = selinux_sock(newsk); + + newsksec->nlbl_state = sksec->nlbl_state; +} + +/** * selinux_netlbl_socket_post_create - Label a socket using NetLabel - * @sock: the socket to label + * @sk: the sock to label * @family: protocol family * * Description: @@ -304,16 +395,19 @@ void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family) int selinux_netlbl_socket_post_create(struct sock *sk, u16 family) { int rc; - struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *sksec = selinux_sock(sk); struct netlbl_lsm_secattr *secattr; - if (family != PF_INET) + if (family != PF_INET && family != PF_INET6) return 0; secattr = selinux_netlbl_sock_genattr(sk); - if (secattr == NULL) - return -ENOMEM; - rc = netlbl_sock_setattr(sk, family, secattr); + if (IS_ERR(secattr)) + return PTR_ERR(secattr); + /* On socket creation, replacement of IP options is safe even if + * the caller does not hold the socket lock. + */ + rc = netlbl_sock_setattr(sk, family, secattr, true); switch (rc) { case 0: sksec->nlbl_state = NLBL_LABELED; @@ -356,7 +450,8 @@ int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, netlbl_secattr_init(&secattr); rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE) - rc = selinux_netlbl_sidlookup_cached(skb, &secattr, &nlbl_sid); + rc = selinux_netlbl_sidlookup_cached(skb, family, + &secattr, &nlbl_sid); else nlbl_sid = SECINITSID_UNLABELED; netlbl_secattr_destroy(&secattr); @@ -379,11 +474,26 @@ int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec, return 0; if (nlbl_sid != SECINITSID_UNLABELED) - netlbl_skbuff_err(skb, rc, 0); + netlbl_skbuff_err(skb, family, rc, 0); return rc; } /** + * selinux_netlbl_option - Is this a NetLabel option + * @level: the socket level or protocol + * @optname: the socket option name + * + * Description: + * Returns true if @level and @optname refer to a NetLabel option. + * Helper for selinux_netlbl_socket_setsockopt(). + */ +static inline int selinux_netlbl_option(int level, int optname) +{ + return (level == IPPROTO_IP && optname == IP_OPTIONS) || + (level == IPPROTO_IPV6 && optname == IPV6_HOPOPTS); +} + +/** * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel * @sock: the socket * @level: the socket level or protocol @@ -402,14 +512,17 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, { int rc = 0; struct sock *sk = sock->sk; - struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *sksec = selinux_sock(sk); struct netlbl_lsm_secattr secattr; - if (level == IPPROTO_IP && optname == IP_OPTIONS && + if (selinux_netlbl_option(level, optname) && (sksec->nlbl_state == NLBL_LABELED || 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) @@ -423,7 +536,8 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, } /** - * selinux_netlbl_socket_connect - Label a client-side socket on connect + * selinux_netlbl_socket_connect_helper - Help label a client-side socket on + * connect * @sk: the socket to label * @addr: the destination address * @@ -432,19 +546,13 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock, * Returns zero values on success, negative values on failure. * */ -int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr) +static int selinux_netlbl_socket_connect_helper(struct sock *sk, + struct sockaddr *addr) { int rc; - struct sk_security_struct *sksec = sk->sk_security; + struct sk_security_struct *sksec = selinux_sock(sk); 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 */ @@ -452,19 +560,60 @@ int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr) netlbl_sock_delattr(sk); sksec->nlbl_state = NLBL_REQSKB; rc = 0; - goto socket_connect_return; + return rc; } secattr = selinux_netlbl_sock_genattr(sk); - if (secattr == NULL) { - rc = -ENOMEM; - goto socket_connect_return; - } + if (IS_ERR(secattr)) + return PTR_ERR(secattr); + 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; +} + +/** + * selinux_netlbl_socket_connect_locked - Label a client-side socket on + * connect + * @sk: the socket to label + * @addr: the destination address + * + * Description: + * Attempt to label a connected socket that already has the socket locked + * with NetLabel using the given address. + * Returns zero values on success, negative values on failure. + * + */ +int selinux_netlbl_socket_connect_locked(struct sock *sk, + struct sockaddr *addr) +{ + struct sk_security_struct *sksec = selinux_sock(sk); + + if (sksec->nlbl_state != NLBL_REQSKB && + sksec->nlbl_state != NLBL_CONNLABELED) + return 0; + + return selinux_netlbl_socket_connect_helper(sk, addr); +} + +/** + * 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; + + lock_sock(sk); + rc = selinux_netlbl_socket_connect_locked(sk, addr); + release_sock(sk); + return rc; } |