diff --git a/drivers/net/tun.c b/drivers/net/tun.c index af372d0957f..c81680dc10e 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -185,6 +185,7 @@ struct tun_struct { unsigned long ageing_time; unsigned int numdisabled; struct list_head disabled; + void *security; }; static inline u32 tun_hashfn(u32 rxhash) @@ -490,6 +491,10 @@ static int tun_attach(struct tun_struct *tun, struct file *file) struct tun_file *tfile = file->private_data; int err; + err = security_tun_dev_attach(tfile->socket.sk, tun->security); + if (err < 0) + goto out; + err = -EINVAL; if (rtnl_dereference(tfile->tun)) goto out; @@ -1373,6 +1378,7 @@ static void tun_free_netdev(struct net_device *dev) BUG_ON(!(list_empty(&tun->disabled))); tun_flow_uninit(tun); + security_tun_dev_free_security(tun->security); free_netdev(dev); } @@ -1562,7 +1568,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (tun_not_capable(tun)) return -EPERM; - err = security_tun_dev_attach(tfile->socket.sk); + err = security_tun_dev_open(tun->security); if (err < 0) return err; @@ -1619,7 +1625,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) spin_lock_init(&tun->lock); - security_tun_dev_post_create(&tfile->sk); + err = security_tun_dev_alloc_security(&tun->security); + if (err < 0) + goto err_free_dev; tun_net_init(dev); @@ -1789,10 +1797,14 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr) if (ifr->ifr_flags & IFF_ATTACH_QUEUE) { tun = tfile->detached; - if (!tun) + if (!tun) { ret = -EINVAL; - else - ret = tun_attach(tun, file); + goto unlock; + } + ret = security_tun_dev_attach_queue(tun->security); + if (ret < 0) + goto unlock; + ret = tun_attach(tun, file); } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) { tun = rtnl_dereference(tfile->tun); if (!tun || !(tun->flags & TUN_TAP_MQ)) @@ -1802,6 +1814,7 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr) } else ret = -EINVAL; +unlock: rtnl_unlock(); return ret; } diff --git a/include/linux/security.h b/include/linux/security.h index 0f6afc657f7..eee7478cda7 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -989,17 +989,29 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * tells the LSM to decrement the number of secmark labeling rules loaded * @req_classify_flow: * Sets the flow's sid to the openreq sid. + * @tun_dev_alloc_security: + * This hook allows a module to allocate a security structure for a TUN + * device. + * @security pointer to a security structure pointer. + * Returns a zero on success, negative values on failure. + * @tun_dev_free_security: + * This hook allows a module to free the security structure for a TUN + * device. + * @security pointer to the TUN device's security structure * @tun_dev_create: * Check permissions prior to creating a new TUN device. - * @tun_dev_post_create: - * This hook allows a module to update or allocate a per-socket security - * structure. - * @sk contains the newly created sock structure. + * @tun_dev_attach_queue: + * Check permissions prior to attaching to a TUN device queue. + * @security pointer to the TUN device's security structure. * @tun_dev_attach: - * Check permissions prior to attaching to a persistent TUN device. This - * hook can also be used by the module to update any security state + * This hook can be used by the module to update any security state * associated with the TUN device's sock structure. * @sk contains the existing sock structure. + * @security pointer to the TUN device's security structure. + * @tun_dev_open: + * This hook can be used by the module to update any security state + * associated with the TUN device's security structure. + * @security pointer to the TUN devices's security structure. * * Security hooks for XFRM operations. * @@ -1620,9 +1632,12 @@ struct security_operations { void (*secmark_refcount_inc) (void); void (*secmark_refcount_dec) (void); void (*req_classify_flow) (const struct request_sock *req, struct flowi *fl); - int (*tun_dev_create)(void); - void (*tun_dev_post_create)(struct sock *sk); - int (*tun_dev_attach)(struct sock *sk); + int (*tun_dev_alloc_security) (void **security); + void (*tun_dev_free_security) (void *security); + int (*tun_dev_create) (void); + int (*tun_dev_attach_queue) (void *security); + int (*tun_dev_attach) (struct sock *sk, void *security); + int (*tun_dev_open) (void *security); #endif /* CONFIG_SECURITY_NETWORK */ #ifdef CONFIG_SECURITY_NETWORK_XFRM @@ -2566,9 +2581,12 @@ void security_inet_conn_established(struct sock *sk, int security_secmark_relabel_packet(u32 secid); void security_secmark_refcount_inc(void); void security_secmark_refcount_dec(void); +int security_tun_dev_alloc_security(void **security); +void security_tun_dev_free_security(void *security); int security_tun_dev_create(void); -void security_tun_dev_post_create(struct sock *sk); -int security_tun_dev_attach(struct sock *sk); +int security_tun_dev_attach_queue(void *security); +int security_tun_dev_attach(struct sock *sk, void *security); +int security_tun_dev_open(void *security); #else /* CONFIG_SECURITY_NETWORK */ static inline int security_unix_stream_connect(struct sock *sock, @@ -2733,16 +2751,31 @@ static inline void security_secmark_refcount_dec(void) { } +static inline int security_tun_dev_alloc_security(void **security) +{ + return 0; +} + +static inline void security_tun_dev_free_security(void *security) +{ +} + static inline int security_tun_dev_create(void) { return 0; } -static inline void security_tun_dev_post_create(struct sock *sk) +static inline int security_tun_dev_attach_queue(void *security) { + return 0; } -static inline int security_tun_dev_attach(struct sock *sk) +static inline int security_tun_dev_attach(struct sock *sk, void *security) +{ + return 0; +} + +static inline int security_tun_dev_open(void *security) { return 0; } diff --git a/security/capability.c b/security/capability.c index 0fe5a026aef..57977508896 100644 --- a/security/capability.c +++ b/security/capability.c @@ -709,16 +709,31 @@ static void cap_req_classify_flow(const struct request_sock *req, { } +static int cap_tun_dev_alloc_security(void **security) +{ + return 0; +} + +static void cap_tun_dev_free_security(void *security) +{ +} + static int cap_tun_dev_create(void) { return 0; } -static void cap_tun_dev_post_create(struct sock *sk) +static int cap_tun_dev_attach_queue(void *security) { + return 0; } -static int cap_tun_dev_attach(struct sock *sk) +static int cap_tun_dev_attach(struct sock *sk, void *security) +{ + return 0; +} + +static int cap_tun_dev_open(void *security) { return 0; } @@ -1050,8 +1065,11 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, secmark_refcount_inc); set_to_cap_if_null(ops, secmark_refcount_dec); set_to_cap_if_null(ops, req_classify_flow); + set_to_cap_if_null(ops, tun_dev_alloc_security); + set_to_cap_if_null(ops, tun_dev_free_security); set_to_cap_if_null(ops, tun_dev_create); - set_to_cap_if_null(ops, tun_dev_post_create); + set_to_cap_if_null(ops, tun_dev_open); + set_to_cap_if_null(ops, tun_dev_attach_queue); set_to_cap_if_null(ops, tun_dev_attach); #endif /* CONFIG_SECURITY_NETWORK */ #ifdef CONFIG_SECURITY_NETWORK_XFRM diff --git a/security/security.c b/security/security.c index daa97f4ac9d..7b88c6aeaed 100644 --- a/security/security.c +++ b/security/security.c @@ -1254,24 +1254,42 @@ void security_secmark_refcount_dec(void) } EXPORT_SYMBOL(security_secmark_refcount_dec); +int security_tun_dev_alloc_security(void **security) +{ + return security_ops->tun_dev_alloc_security(security); +} +EXPORT_SYMBOL(security_tun_dev_alloc_security); + +void security_tun_dev_free_security(void *security) +{ + security_ops->tun_dev_free_security(security); +} +EXPORT_SYMBOL(security_tun_dev_free_security); + int security_tun_dev_create(void) { return security_ops->tun_dev_create(); } EXPORT_SYMBOL(security_tun_dev_create); -void security_tun_dev_post_create(struct sock *sk) +int security_tun_dev_attach_queue(void *security) { - return security_ops->tun_dev_post_create(sk); + return security_ops->tun_dev_attach_queue(security); } -EXPORT_SYMBOL(security_tun_dev_post_create); +EXPORT_SYMBOL(security_tun_dev_attach_queue); -int security_tun_dev_attach(struct sock *sk) +int security_tun_dev_attach(struct sock *sk, void *security) { - return security_ops->tun_dev_attach(sk); + return security_ops->tun_dev_attach(sk, security); } EXPORT_SYMBOL(security_tun_dev_attach); +int security_tun_dev_open(void *security) +{ + return security_ops->tun_dev_open(security); +} +EXPORT_SYMBOL(security_tun_dev_open); + #endif /* CONFIG_SECURITY_NETWORK */ #ifdef CONFIG_SECURITY_NETWORK_XFRM diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 61a53367d02..ef26e9611ff 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4399,6 +4399,24 @@ static void selinux_req_classify_flow(const struct request_sock *req, fl->flowi_secid = req->secid; } +static int selinux_tun_dev_alloc_security(void **security) +{ + struct tun_security_struct *tunsec; + + tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL); + if (!tunsec) + return -ENOMEM; + tunsec->sid = current_sid(); + + *security = tunsec; + return 0; +} + +static void selinux_tun_dev_free_security(void *security) +{ + kfree(security); +} + static int selinux_tun_dev_create(void) { u32 sid = current_sid(); @@ -4414,8 +4432,17 @@ static int selinux_tun_dev_create(void) NULL); } -static void selinux_tun_dev_post_create(struct sock *sk) +static int selinux_tun_dev_attach_queue(void *security) { + struct tun_security_struct *tunsec = security; + + return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET, + TUN_SOCKET__ATTACH_QUEUE, NULL); +} + +static int selinux_tun_dev_attach(struct sock *sk, void *security) +{ + struct tun_security_struct *tunsec = security; struct sk_security_struct *sksec = sk->sk_security; /* we don't currently perform any NetLabel based labeling here and it @@ -4425,20 +4452,19 @@ static void selinux_tun_dev_post_create(struct sock *sk) * cause confusion to the TUN user that had no idea network labeling * protocols were being used */ - /* see the comments in selinux_tun_dev_create() about why we don't use - * the sockcreate SID here */ - - sksec->sid = current_sid(); + sksec->sid = tunsec->sid; sksec->sclass = SECCLASS_TUN_SOCKET; + + return 0; } -static int selinux_tun_dev_attach(struct sock *sk) +static int selinux_tun_dev_open(void *security) { - struct sk_security_struct *sksec = sk->sk_security; + struct tun_security_struct *tunsec = security; u32 sid = current_sid(); int err; - err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET, + err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__RELABELFROM, NULL); if (err) return err; @@ -4446,8 +4472,7 @@ static int selinux_tun_dev_attach(struct sock *sk) TUN_SOCKET__RELABELTO, NULL); if (err) return err; - - sksec->sid = sid; + tunsec->sid = sid; return 0; } @@ -5642,9 +5667,12 @@ static struct security_operations selinux_ops = { .secmark_refcount_inc = selinux_secmark_refcount_inc, .secmark_refcount_dec = selinux_secmark_refcount_dec, .req_classify_flow = selinux_req_classify_flow, + .tun_dev_alloc_security = selinux_tun_dev_alloc_security, + .tun_dev_free_security = selinux_tun_dev_free_security, .tun_dev_create = selinux_tun_dev_create, - .tun_dev_post_create = selinux_tun_dev_post_create, + .tun_dev_attach_queue = selinux_tun_dev_attach_queue, .tun_dev_attach = selinux_tun_dev_attach, + .tun_dev_open = selinux_tun_dev_open, #ifdef CONFIG_SECURITY_NETWORK_XFRM .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc, diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h index 26c7eee1c30..aa47bcabb5f 100644 --- a/security/selinux/include/objsec.h +++ b/security/selinux/include/objsec.h @@ -110,6 +110,10 @@ struct sk_security_struct { u16 sclass; /* sock security class */ }; +struct tun_security_struct { + u32 sid; /* SID for the tun device sockets */ +}; + struct key_security_struct { u32 sid; /* SID of key */ };