diff options
Diffstat (limited to 'security/selinux/hooks.c')
-rw-r--r-- | security/selinux/hooks.c | 305 |
1 files changed, 212 insertions, 93 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 03fc6a81ae3..3e3fde7c1d2 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -75,6 +75,7 @@ #include <linux/string.h> #include <linux/selinux.h> #include <linux/mutex.h> +#include <linux/posix-timers.h> #include "avc.h" #include "objsec.h" @@ -291,6 +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); } @@ -324,7 +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"}, @@ -957,7 +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; @@ -1290,7 +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); @@ -2120,7 +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(); @@ -2138,8 +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(); @@ -2321,13 +2323,7 @@ static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm) initrlim = init_task.signal->rlim+i; rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur); } - if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { - /* - * This will cause RLIMIT_CPU calculations - * to be refigured. - */ - current->it_prof_expires = jiffies_to_cputime(1); - } + update_rlimit_cpu(rlim->rlim_cur); } /* Wake up the parent if it is waiting so that it can @@ -3548,38 +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; } /** @@ -3794,6 +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; @@ -3807,7 +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; @@ -3841,6 +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; } @@ -4070,20 +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; @@ -4092,12 +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; @@ -4111,6 +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; @@ -4119,6 +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; @@ -4126,15 +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); @@ -4142,13 +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) @@ -4207,10 +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; @@ -4268,8 +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, @@ -4277,10 +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) { @@ -4315,12 +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, @@ -4370,39 +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; } @@ -4426,6 +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, @@ -4493,30 +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; @@ -4530,23 +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 @@ -4562,21 +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)) @@ -5219,8 +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; @@ -5228,11 +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, @@ -5641,6 +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, } }; |