Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp...
[safe/jmp/linux-2.6] / security / selinux / hooks.c
index 6964978..3e3fde7 100644 (file)
@@ -292,6 +292,7 @@ static void sk_free_security(struct sock *sk)
        struct sk_security_struct *ssec = sk->sk_security;
 
        sk->sk_security = NULL;
+       selinux_netlbl_sk_security_free(ssec);
        kfree(ssec);
 }
 
@@ -325,7 +326,7 @@ enum {
        Opt_rootcontext = 4,
 };
 
-static match_table_t tokens = {
+static const match_table_t tokens = {
        {Opt_context, CONTEXT_STR "%s"},
        {Opt_fscontext, FSCONTEXT_STR "%s"},
        {Opt_defcontext, DEFCONTEXT_STR "%s"},
@@ -958,7 +959,8 @@ out_err:
        return rc;
 }
 
-void selinux_write_opts(struct seq_file *m, struct security_mnt_opts *opts)
+static void selinux_write_opts(struct seq_file *m,
+                              struct security_mnt_opts *opts)
 {
        int i;
        char *prefix;
@@ -1291,7 +1293,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
                /* Default to the fs superblock SID. */
                isec->sid = sbsec->sid;
 
-               if (sbsec->proc) {
+               if (sbsec->proc && !S_ISLNK(inode->i_mode)) {
                        struct proc_inode *proci = PROC_I(inode);
                        if (proci->pde) {
                                isec->sclass = inode_mode_to_security_class(inode->i_mode);
@@ -2121,7 +2123,6 @@ static inline void flush_unauthorized_files(struct files_struct *files)
        long j = -1;
        int drop_tty = 0;
 
-       mutex_lock(&tty_mutex);
        tty = get_current_tty();
        if (tty) {
                file_list_lock();
@@ -2139,8 +2140,8 @@ static inline void flush_unauthorized_files(struct files_struct *files)
                        }
                }
                file_list_unlock();
+               tty_kref_put(tty);
        }
-       mutex_unlock(&tty_mutex);
        /* Reset controlling tty. */
        if (drop_tty)
                no_tty();
@@ -3543,38 +3544,44 @@ out:
 #endif /* IPV6 */
 
 static int selinux_parse_skb(struct sk_buff *skb, struct avc_audit_data *ad,
-                            char **addrp, int src, u8 *proto)
+                            char **_addrp, int src, u8 *proto)
 {
-       int ret = 0;
+       char *addrp;
+       int ret;
 
        switch (ad->u.net.family) {
        case PF_INET:
                ret = selinux_parse_skb_ipv4(skb, ad, proto);
-               if (ret || !addrp)
-                       break;
-               *addrp = (char *)(src ? &ad->u.net.v4info.saddr :
-                                       &ad->u.net.v4info.daddr);
-               break;
+               if (ret)
+                       goto parse_error;
+               addrp = (char *)(src ? &ad->u.net.v4info.saddr :
+                                      &ad->u.net.v4info.daddr);
+               goto okay;
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
        case PF_INET6:
                ret = selinux_parse_skb_ipv6(skb, ad, proto);
-               if (ret || !addrp)
-                       break;
-               *addrp = (char *)(src ? &ad->u.net.v6info.saddr :
-                                       &ad->u.net.v6info.daddr);
-               break;
+               if (ret)
+                       goto parse_error;
+               addrp = (char *)(src ? &ad->u.net.v6info.saddr :
+                                      &ad->u.net.v6info.daddr);
+               goto okay;
 #endif /* IPV6 */
        default:
-               break;
+               addrp = NULL;
+               goto okay;
        }
 
-       if (unlikely(ret))
-               printk(KERN_WARNING
-                      "SELinux: failure in selinux_parse_skb(),"
-                      " unable to parse packet\n");
-
+parse_error:
+       printk(KERN_WARNING
+              "SELinux: failure in selinux_parse_skb(),"
+              " unable to parse packet\n");
        return ret;
+
+okay:
+       if (_addrp)
+               *_addrp = addrp;
+       return 0;
 }
 
 /**
@@ -3789,6 +3796,7 @@ out:
 
 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
 {
+       struct sock *sk = sock->sk;
        struct inode_security_struct *isec;
        int err;
 
@@ -3802,7 +3810,6 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
        isec = SOCK_INODE(sock)->i_security;
        if (isec->sclass == SECCLASS_TCP_SOCKET ||
            isec->sclass == SECCLASS_DCCP_SOCKET) {
-               struct sock *sk = sock->sk;
                struct avc_audit_data ad;
                struct sockaddr_in *addr4 = NULL;
                struct sockaddr_in6 *addr6 = NULL;
@@ -3836,6 +3843,8 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
                        goto out;
        }
 
+       err = selinux_netlbl_socket_connect(sk, address);
+
 out:
        return err;
 }
@@ -4065,20 +4074,28 @@ static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
 }
 
 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
-                                      struct avc_audit_data *ad,
-                                      u16 family, char *addrp)
+                                      u16 family)
 {
        int err;
        struct sk_security_struct *sksec = sk->sk_security;
        u32 peer_sid;
        u32 sk_sid = sksec->sid;
+       struct avc_audit_data ad;
+       char *addrp;
+
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = skb->iif;
+       ad.u.net.family = family;
+       err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
+       if (err)
+               return err;
 
        if (selinux_compat_net)
-               err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
+               err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
                                                           family, addrp);
        else
                err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
-                                  PACKET__RECV, ad);
+                                  PACKET__RECV, &ad);
        if (err)
                return err;
 
@@ -4087,12 +4104,14 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
                if (err)
                        return err;
                err = avc_has_perm(sk_sid, peer_sid,
-                                  SECCLASS_PEER, PEER__RECV, ad);
+                                  SECCLASS_PEER, PEER__RECV, &ad);
+               if (err)
+                       selinux_netlbl_err(skb, err, 0);
        } else {
-               err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
+               err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
                if (err)
                        return err;
-               err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
+               err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
        }
 
        return err;
@@ -4106,6 +4125,8 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        u32 sk_sid = sksec->sid;
        struct avc_audit_data ad;
        char *addrp;
+       u8 secmark_active;
+       u8 peerlbl_active;
 
        if (family != PF_INET && family != PF_INET6)
                return 0;
@@ -4114,6 +4135,18 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
                family = PF_INET;
 
+       /* If any sort of compatibility mode is enabled then handoff processing
+        * to the selinux_sock_rcv_skb_compat() function to deal with the
+        * special handling.  We do this in an attempt to keep this function
+        * as fast and as clean as possible. */
+       if (selinux_compat_net || !selinux_policycap_netpeer)
+               return selinux_sock_rcv_skb_compat(sk, skb, family);
+
+       secmark_active = selinux_secmark_enabled();
+       peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+       if (!secmark_active && !peerlbl_active)
+               return 0;
+
        AVC_AUDIT_DATA_INIT(&ad, NET);
        ad.u.net.netif = skb->iif;
        ad.u.net.family = family;
@@ -4121,15 +4154,7 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        if (err)
                return err;
 
-       /* If any sort of compatibility mode is enabled then handoff processing
-        * to the selinux_sock_rcv_skb_compat() function to deal with the
-        * special handling.  We do this in an attempt to keep this function
-        * as fast and as clean as possible. */
-       if (selinux_compat_net || !selinux_policycap_netpeer)
-               return selinux_sock_rcv_skb_compat(sk, skb, &ad,
-                                                  family, addrp);
-
-       if (netlbl_enabled() || selinux_xfrm_enabled()) {
+       if (peerlbl_active) {
                u32 peer_sid;
 
                err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
@@ -4137,13 +4162,17 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
                        return err;
                err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
                                               peer_sid, &ad);
-               if (err)
+               if (err) {
+                       selinux_netlbl_err(skb, err, 0);
                        return err;
+               }
                err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
                                   PEER__RECV, &ad);
+               if (err)
+                       selinux_netlbl_err(skb, err, 0);
        }
 
-       if (selinux_secmark_enabled()) {
+       if (secmark_active) {
                err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
                                   PACKET__RECV, &ad);
                if (err)
@@ -4202,10 +4231,12 @@ static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *
        u32 peer_secid = SECSID_NULL;
        u16 family;
 
-       if (sock)
+       if (skb && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+       else if (skb && skb->protocol == htons(ETH_P_IPV6))
+               family = PF_INET6;
+       else if (sock)
                family = sock->sk->sk_family;
-       else if (skb && skb->sk)
-               family = skb->sk->sk_family;
        else
                goto out;
 
@@ -4263,8 +4294,6 @@ static void selinux_sock_graft(struct sock *sk, struct socket *parent)
            sk->sk_family == PF_UNIX)
                isec->sid = sksec->sid;
        sksec->sclass = isec->sclass;
-
-       selinux_netlbl_sock_graft(sk, parent);
 }
 
 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
@@ -4272,10 +4301,15 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 {
        struct sk_security_struct *sksec = sk->sk_security;
        int err;
+       u16 family = sk->sk_family;
        u32 newsid;
        u32 peersid;
 
-       err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
+       /* handle mapped IPv4 packets arriving via IPv6 sockets */
+       if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+
+       err = selinux_skb_peerlbl_sid(skb, family, &peersid);
        if (err)
                return err;
        if (peersid == SECSID_NULL) {
@@ -4310,12 +4344,18 @@ static void selinux_inet_csk_clone(struct sock *newsk,
        selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
 }
 
-static void selinux_inet_conn_established(struct sock *sk,
-                               struct sk_buff *skb)
+static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
 {
+       u16 family = sk->sk_family;
        struct sk_security_struct *sksec = sk->sk_security;
 
-       selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
+       /* handle mapped IPv4 packets arriving via IPv6 sockets */
+       if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+
+       selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
+
+       selinux_netlbl_inet_conn_established(sk, family);
 }
 
 static void selinux_req_classify_flow(const struct request_sock *req,
@@ -4365,39 +4405,54 @@ out:
 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
                                       u16 family)
 {
+       int err;
        char *addrp;
        u32 peer_sid;
        struct avc_audit_data ad;
        u8 secmark_active;
+       u8 netlbl_active;
        u8 peerlbl_active;
 
        if (!selinux_policycap_netpeer)
                return NF_ACCEPT;
 
        secmark_active = selinux_secmark_enabled();
-       peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+       netlbl_active = netlbl_enabled();
+       peerlbl_active = netlbl_active || selinux_xfrm_enabled();
        if (!secmark_active && !peerlbl_active)
                return NF_ACCEPT;
 
+       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
+               return NF_DROP;
+
        AVC_AUDIT_DATA_INIT(&ad, NET);
        ad.u.net.netif = ifindex;
        ad.u.net.family = family;
        if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
                return NF_DROP;
 
-       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
-               return NF_DROP;
-
-       if (peerlbl_active)
-               if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
-                                            peer_sid, &ad) != 0)
+       if (peerlbl_active) {
+               err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
+                                              peer_sid, &ad);
+               if (err) {
+                       selinux_netlbl_err(skb, err, 1);
                        return NF_DROP;
+               }
+       }
 
        if (secmark_active)
                if (avc_has_perm(peer_sid, skb->secmark,
                                 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
                        return NF_DROP;
 
+       if (netlbl_active)
+               /* we do this in the FORWARD path and not the POST_ROUTING
+                * path because we want to make sure we apply the necessary
+                * labeling before IPsec is applied so we can leverage AH
+                * protection */
+               if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
+                       return NF_DROP;
+
        return NF_ACCEPT;
 }
 
@@ -4421,6 +4476,37 @@ static unsigned int selinux_ipv6_forward(unsigned int hooknum,
 }
 #endif /* IPV6 */
 
+static unsigned int selinux_ip_output(struct sk_buff *skb,
+                                     u16 family)
+{
+       u32 sid;
+
+       if (!netlbl_enabled())
+               return NF_ACCEPT;
+
+       /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
+        * because we want to make sure we apply the necessary labeling
+        * before IPsec is applied so we can leverage AH protection */
+       if (skb->sk) {
+               struct sk_security_struct *sksec = skb->sk->sk_security;
+               sid = sksec->sid;
+       } else
+               sid = SECINITSID_KERNEL;
+       if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
+               return NF_DROP;
+
+       return NF_ACCEPT;
+}
+
+static unsigned int selinux_ipv4_output(unsigned int hooknum,
+                                       struct sk_buff *skb,
+                                       const struct net_device *in,
+                                       const struct net_device *out,
+                                       int (*okfn)(struct sk_buff *))
+{
+       return selinux_ip_output(skb, PF_INET);
+}
+
 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
                                                int ifindex,
                                                struct avc_audit_data *ad,
@@ -4488,30 +4574,36 @@ static int selinux_ip_postroute_iptables_compat(struct sock *sk,
 
 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
                                                int ifindex,
-                                               struct avc_audit_data *ad,
-                                               u16 family,
-                                               char *addrp,
-                                               u8 proto)
+                                               u16 family)
 {
        struct sock *sk = skb->sk;
        struct sk_security_struct *sksec;
+       struct avc_audit_data ad;
+       char *addrp;
+       u8 proto;
 
        if (sk == NULL)
                return NF_ACCEPT;
        sksec = sk->sk_security;
 
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = ifindex;
+       ad.u.net.family = family;
+       if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
+               return NF_DROP;
+
        if (selinux_compat_net) {
                if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
-                                                        ad, family, addrp))
+                                                        &ad, family, addrp))
                        return NF_DROP;
        } else {
                if (avc_has_perm(sksec->sid, skb->secmark,
-                                SECCLASS_PACKET, PACKET__SEND, ad))
+                                SECCLASS_PACKET, PACKET__SEND, &ad))
                        return NF_DROP;
        }
 
        if (selinux_policycap_netpeer)
-               if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
+               if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
                        return NF_DROP;
 
        return NF_ACCEPT;
@@ -4525,23 +4617,15 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
        struct sock *sk;
        struct avc_audit_data ad;
        char *addrp;
-       u8 proto;
        u8 secmark_active;
        u8 peerlbl_active;
 
-       AVC_AUDIT_DATA_INIT(&ad, NET);
-       ad.u.net.netif = ifindex;
-       ad.u.net.family = family;
-       if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
-               return NF_DROP;
-
        /* If any sort of compatibility mode is enabled then handoff processing
         * to the selinux_ip_postroute_compat() function to deal with the
         * special handling.  We do this in an attempt to keep this function
         * as fast and as clean as possible. */
        if (selinux_compat_net || !selinux_policycap_netpeer)
-               return selinux_ip_postroute_compat(skb, ifindex, &ad,
-                                                  family, addrp, proto);
+               return selinux_ip_postroute_compat(skb, ifindex, family);
 
        /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
         * packet transformation so allow the packet to pass without any checks
@@ -4557,21 +4641,45 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
        if (!secmark_active && !peerlbl_active)
                return NF_ACCEPT;
 
-       /* if the packet is locally generated (skb->sk != NULL) then use the
-        * socket's label as the peer label, otherwise the packet is being
-        * forwarded through this system and we need to fetch the peer label
-        * directly from the packet */
+       /* if the packet is being forwarded then get the peer label from the
+        * packet itself; otherwise check to see if it is from a local
+        * application or the kernel, if from an application get the peer label
+        * from the sending socket, otherwise use the kernel's sid */
        sk = skb->sk;
-       if (sk) {
+       if (sk == NULL) {
+               switch (family) {
+               case PF_INET:
+                       if (IPCB(skb)->flags & IPSKB_FORWARDED)
+                               secmark_perm = PACKET__FORWARD_OUT;
+                       else
+                               secmark_perm = PACKET__SEND;
+                       break;
+               case PF_INET6:
+                       if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
+                               secmark_perm = PACKET__FORWARD_OUT;
+                       else
+                               secmark_perm = PACKET__SEND;
+                       break;
+               default:
+                       return NF_DROP;
+               }
+               if (secmark_perm == PACKET__FORWARD_OUT) {
+                       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
+                               return NF_DROP;
+               } else
+                       peer_sid = SECINITSID_KERNEL;
+       } else {
                struct sk_security_struct *sksec = sk->sk_security;
                peer_sid = sksec->sid;
                secmark_perm = PACKET__SEND;
-       } else {
-               if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
-                               return NF_DROP;
-               secmark_perm = PACKET__FORWARD_OUT;
        }
 
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = ifindex;
+       ad.u.net.family = family;
+       if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
+               return NF_DROP;
+
        if (secmark_active)
                if (avc_has_perm(peer_sid, skb->secmark,
                                 SECCLASS_PACKET, secmark_perm, &ad))
@@ -5214,8 +5322,12 @@ static int selinux_setprocattr(struct task_struct *p,
 
                if (sid == 0)
                        return -EINVAL;
-
-               /* Only allow single threaded processes to change context */
+               /*
+                * SELinux allows to change context in the following case only.
+                *  - Single threaded processes.
+                *  - Multi threaded processes intend to change its context into
+                *    more restricted domain (defined by TYPEBOUNDS statement).
+                */
                if (atomic_read(&p->mm->mm_users) != 1) {
                        struct task_struct *g, *t;
                        struct mm_struct *mm = p->mm;
@@ -5223,11 +5335,16 @@ static int selinux_setprocattr(struct task_struct *p,
                        do_each_thread(g, t) {
                                if (t->mm == mm && t != p) {
                                        read_unlock(&tasklist_lock);
-                                       return -EPERM;
+                                       error = security_bounded_transition(tsec->sid, sid);
+                                       if (!error)
+                                               goto boundary_ok;
+
+                                       return error;
                                }
                        } while_each_thread(g, t);
                        read_unlock(&tasklist_lock);
                }
+boundary_ok:
 
                /* Check permissions for the transition. */
                error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
@@ -5636,6 +5753,13 @@ static struct nf_hook_ops selinux_ipv4_ops[] = {
                .pf =           PF_INET,
                .hooknum =      NF_INET_FORWARD,
                .priority =     NF_IP_PRI_SELINUX_FIRST,
+       },
+       {
+               .hook =         selinux_ipv4_output,
+               .owner =        THIS_MODULE,
+               .pf =           PF_INET,
+               .hooknum =      NF_INET_LOCAL_OUT,
+               .priority =     NF_IP_PRI_SELINUX_FIRST,
        }
 };