diff options
Diffstat (limited to 'net/netlabel/netlabel_unlabeled.c')
| -rw-r--r-- | net/netlabel/netlabel_unlabeled.c | 1570 |
1 files changed, 1570 insertions, 0 deletions
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c new file mode 100644 index 000000000..0067f4723 --- /dev/null +++ b/net/netlabel/netlabel_unlabeled.c @@ -0,0 +1,1570 @@ +/* + * NetLabel Unlabeled Support + * + * This file defines functions for dealing with unlabeled packets for the + * NetLabel system. The NetLabel system manages static and dynamic label + * mappings for network protocols such as CIPSO and RIPSO. + * + * Author: Paul Moore <paul@paul-moore.com> + * + */ + +/* + * (c) Copyright Hewlett-Packard Development Company, L.P., 2006 - 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, see <http://www.gnu.org/licenses/>. + * + */ + +#include <linux/types.h> +#include <linux/rcupdate.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/socket.h> +#include <linux/string.h> +#include <linux/skbuff.h> +#include <linux/audit.h> +#include <linux/in.h> +#include <linux/in6.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/notifier.h> +#include <linux/netdevice.h> +#include <linux/security.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <net/netlink.h> +#include <net/genetlink.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <net/net_namespace.h> +#include <net/netlabel.h> +#include <asm/bug.h> +#include <linux/atomic.h> + +#include "netlabel_user.h" +#include "netlabel_addrlist.h" +#include "netlabel_domainhash.h" +#include "netlabel_unlabeled.h" +#include "netlabel_mgmt.h" + +/* NOTE: at present we always use init's network namespace since we don't + * presently support different namespaces even though the majority of + * the functions in this file are "namespace safe" */ + +/* The unlabeled connection hash table which we use to map network interfaces + * and addresses of unlabeled packets to a user specified secid value for the + * LSM. The hash table is used to lookup the network interface entry + * (struct netlbl_unlhsh_iface) and then the interface entry is used to + * lookup an IP address match from an ordered list. If a network interface + * match can not be found in the hash table then the default entry + * (netlbl_unlhsh_def) is used. The IP address entry list + * (struct netlbl_unlhsh_addr) is ordered such that the entries with a + * larger netmask come first. + */ +struct netlbl_unlhsh_tbl { + struct list_head *tbl; + u32 size; +}; +#define netlbl_unlhsh_addr4_entry(iter) \ + container_of(iter, struct netlbl_unlhsh_addr4, list) +struct netlbl_unlhsh_addr4 { + u32 secid; + + struct netlbl_af4list list; + struct rcu_head rcu; +}; +#define netlbl_unlhsh_addr6_entry(iter) \ + container_of(iter, struct netlbl_unlhsh_addr6, list) +struct netlbl_unlhsh_addr6 { + u32 secid; + + struct netlbl_af6list list; + struct rcu_head rcu; +}; +struct netlbl_unlhsh_iface { + int ifindex; + struct list_head addr4_list; + struct list_head addr6_list; + + u32 valid; + struct list_head list; + struct rcu_head rcu; +}; + +/* Argument struct for netlbl_unlhsh_walk() */ +struct netlbl_unlhsh_walk_arg { + struct netlink_callback *nl_cb; + struct sk_buff *skb; + u32 seq; +}; + +/* Unlabeled connection hash table */ +/* updates should be so rare that having one spinlock for the entire + * hash table should be okay */ +static DEFINE_SPINLOCK(netlbl_unlhsh_lock); +#define netlbl_unlhsh_rcu_deref(p) \ + rcu_dereference_check(p, lockdep_is_held(&netlbl_unlhsh_lock)) +static struct netlbl_unlhsh_tbl __rcu *netlbl_unlhsh; +static struct netlbl_unlhsh_iface __rcu *netlbl_unlhsh_def; + +/* Accept unlabeled packets flag */ +static u8 netlabel_unlabel_acceptflg; + +/* NetLabel Generic NETLINK unlabeled family */ +static struct genl_family netlbl_unlabel_gnl_family; + +/* NetLabel Netlink attribute policy */ +static const struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = { + [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 }, + [NLBL_UNLABEL_A_IPV6ADDR] = { .type = NLA_BINARY, + .len = sizeof(struct in6_addr) }, + [NLBL_UNLABEL_A_IPV6MASK] = { .type = NLA_BINARY, + .len = sizeof(struct in6_addr) }, + [NLBL_UNLABEL_A_IPV4ADDR] = { .type = NLA_BINARY, + .len = sizeof(struct in_addr) }, + [NLBL_UNLABEL_A_IPV4MASK] = { .type = NLA_BINARY, + .len = sizeof(struct in_addr) }, + [NLBL_UNLABEL_A_IFACE] = { .type = NLA_NUL_STRING, + .len = IFNAMSIZ - 1 }, + [NLBL_UNLABEL_A_SECCTX] = { .type = NLA_BINARY } +}; + +/* + * Unlabeled Connection Hash Table Functions + */ + +/** + * netlbl_unlhsh_free_iface - Frees an interface entry from the hash table + * @entry: the entry's RCU field + * + * Description: + * This function is designed to be used as a callback to the call_rcu() + * function so that memory allocated to a hash table interface entry can be + * released safely. It is important to note that this function does not free + * the IPv4 and IPv6 address lists contained as part of an interface entry. It + * is up to the rest of the code to make sure an interface entry is only freed + * once it's address lists are empty. + * + */ +static void netlbl_unlhsh_free_iface(struct rcu_head *entry) +{ + struct netlbl_unlhsh_iface *iface; + struct netlbl_af4list *iter4; + struct netlbl_af4list *tmp4; +#if IS_ENABLED(CONFIG_IPV6) + struct netlbl_af6list *iter6; + struct netlbl_af6list *tmp6; +#endif /* IPv6 */ + + iface = container_of(entry, struct netlbl_unlhsh_iface, rcu); + + /* no need for locks here since we are the only one with access to this + * structure */ + + netlbl_af4list_foreach_safe(iter4, tmp4, &iface->addr4_list) { + netlbl_af4list_remove_entry(iter4); + kfree(netlbl_unlhsh_addr4_entry(iter4)); + } +#if IS_ENABLED(CONFIG_IPV6) + netlbl_af6list_foreach_safe(iter6, tmp6, &iface->addr6_list) { + netlbl_af6list_remove_entry(iter6); + kfree(netlbl_unlhsh_addr6_entry(iter6)); + } +#endif /* IPv6 */ + kfree(iface); +} + +/** + * netlbl_unlhsh_hash - Hashing function for the hash table + * @ifindex: the network interface/device to hash + * + * Description: + * This is the hashing function for the unlabeled hash table, it returns the + * bucket number for the given device/interface. The caller is responsible for + * ensuring that the hash table is protected with either a RCU read lock or + * the hash table lock. + * + */ +static u32 netlbl_unlhsh_hash(int ifindex) +{ + return ifindex & (netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->size - 1); +} + +/** + * netlbl_unlhsh_search_iface - Search for a matching interface entry + * @ifindex: the network interface + * + * Description: + * Searches the unlabeled connection hash table and returns a pointer to the + * interface entry which matches @ifindex, otherwise NULL is returned. The + * caller is responsible for ensuring that the hash table is protected with + * either a RCU read lock or the hash table lock. + * + */ +static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex) +{ + u32 bkt; + struct list_head *bkt_list; + struct netlbl_unlhsh_iface *iter; + + bkt = netlbl_unlhsh_hash(ifindex); + bkt_list = &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]; + list_for_each_entry_rcu(iter, bkt_list, list) + if (iter->valid && iter->ifindex == ifindex) + return iter; + + return NULL; +} + +/** + * netlbl_unlhsh_add_addr4 - Add a new IPv4 address entry to the hash table + * @iface: the associated interface entry + * @addr: IPv4 address in network byte order + * @mask: IPv4 address mask in network byte order + * @secid: LSM secid value for entry + * + * Description: + * Add a new address entry into the unlabeled connection hash table using the + * interface entry specified by @iface. On success zero is returned, otherwise + * a negative value is returned. + * + */ +static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface, + const struct in_addr *addr, + const struct in_addr *mask, + u32 secid) +{ + int ret_val; + struct netlbl_unlhsh_addr4 *entry; + + entry = kzalloc(sizeof(*entry), GFP_ATOMIC); + if (entry == NULL) + return -ENOMEM; + + entry->list.addr = addr->s_addr & mask->s_addr; + entry->list.mask = mask->s_addr; + entry->list.valid = 1; + entry->secid = secid; + + spin_lock(&netlbl_unlhsh_lock); + ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list); + spin_unlock(&netlbl_unlhsh_lock); + + if (ret_val != 0) + kfree(entry); + return ret_val; +} + +#if IS_ENABLED(CONFIG_IPV6) +/** + * netlbl_unlhsh_add_addr6 - Add a new IPv6 address entry to the hash table + * @iface: the associated interface entry + * @addr: IPv6 address in network byte order + * @mask: IPv6 address mask in network byte order + * @secid: LSM secid value for entry + * + * Description: + * Add a new address entry into the unlabeled connection hash table using the + * interface entry specified by @iface. On success zero is returned, otherwise + * a negative value is returned. + * + */ +static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface, + const struct in6_addr *addr, + const struct in6_addr *mask, + u32 secid) +{ + int ret_val; + struct netlbl_unlhsh_addr6 *entry; + + entry = kzalloc(sizeof(*entry), GFP_ATOMIC); + if (entry == NULL) + return -ENOMEM; + + entry->list.addr = *addr; + entry->list.addr.s6_addr32[0] &= mask->s6_addr32[0]; + entry->list.addr.s6_addr32[1] &= mask->s6_addr32[1]; + entry->list.addr.s6_addr32[2] &= mask->s6_addr32[2]; + entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3]; + entry->list.mask = *mask; + entry->list.valid = 1; + entry->secid = secid; + + spin_lock(&netlbl_unlhsh_lock); + ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list); + spin_unlock(&netlbl_unlhsh_lock); + + if (ret_val != 0) + kfree(entry); + return 0; +} +#endif /* IPv6 */ + +/** + * netlbl_unlhsh_add_iface - Adds a new interface entry to the hash table + * @ifindex: network interface + * + * Description: + * Add a new, empty, interface entry into the unlabeled connection hash table. + * On success a pointer to the new interface entry is returned, on failure NULL + * is returned. + * + */ +static struct netlbl_unlhsh_iface *netlbl_unlhsh_add_iface(int ifindex) +{ + u32 bkt; + struct netlbl_unlhsh_iface *iface; + + iface = kzalloc(sizeof(*iface), GFP_ATOMIC); + if (iface == NULL) + return NULL; + + iface->ifindex = ifindex; + INIT_LIST_HEAD(&iface->addr4_list); + INIT_LIST_HEAD(&iface->addr6_list); + iface->valid = 1; + + spin_lock(&netlbl_unlhsh_lock); + if (ifindex > 0) { + bkt = netlbl_unlhsh_hash(ifindex); + if (netlbl_unlhsh_search_iface(ifindex) != NULL) + goto add_iface_failure; + list_add_tail_rcu(&iface->list, + &netlbl_unlhsh_rcu_deref(netlbl_unlhsh)->tbl[bkt]); + } else { + INIT_LIST_HEAD(&iface->list); + if (netlbl_unlhsh_rcu_deref(netlbl_unlhsh_def) != NULL) + goto add_iface_failure; + rcu_assign_pointer(netlbl_unlhsh_def, iface); + } + spin_unlock(&netlbl_unlhsh_lock); + + return iface; + +add_iface_failure: + spin_unlock(&netlbl_unlhsh_lock); + kfree(iface); + return NULL; +} + +/** + * netlbl_unlhsh_add - Adds a new entry to the unlabeled connection hash table + * @net: network namespace + * @dev_name: interface name + * @addr: IP address in network byte order + * @mask: address mask in network byte order + * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6) + * @secid: LSM secid value for the entry + * @audit_info: NetLabel audit information + * + * Description: + * Adds a new entry to the unlabeled connection hash table. Returns zero on + * success, negative values on failure. + * + */ +int netlbl_unlhsh_add(struct net *net, + const char *dev_name, + const void *addr, + const void *mask, + u32 addr_len, + u32 secid, + struct netlbl_audit *audit_info) +{ + int ret_val; + int ifindex; + struct net_device *dev; + struct netlbl_unlhsh_iface *iface; + struct audit_buffer *audit_buf = NULL; + char *secctx = NULL; + u32 secctx_len; + + if (addr_len != sizeof(struct in_addr) && + addr_len != sizeof(struct in6_addr)) + return -EINVAL; + + rcu_read_lock(); + if (dev_name != NULL) { + dev = dev_get_by_name_rcu(net, dev_name); + if (dev == NULL) { + ret_val = -ENODEV; + goto unlhsh_add_return; + } + ifindex = dev->ifindex; + iface = netlbl_unlhsh_search_iface(ifindex); + } else { + ifindex = 0; + iface = rcu_dereference(netlbl_unlhsh_def); + } + if (iface == NULL) { + iface = netlbl_unlhsh_add_iface(ifindex); + if (iface == NULL) { + ret_val = -ENOMEM; + goto unlhsh_add_return; + } + } + audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCADD, + audit_info); + switch (addr_len) { + case sizeof(struct in_addr): { + const struct in_addr *addr4 = addr; + const struct in_addr *mask4 = mask; + + ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid); + if (audit_buf != NULL) + netlbl_af4list_audit_addr(audit_buf, 1, + dev_name, + addr4->s_addr, + mask4->s_addr); + break; + } +#if IS_ENABLED(CONFIG_IPV6) + case sizeof(struct in6_addr): { + const struct in6_addr *addr6 = addr; + const struct in6_addr *mask6 = mask; + + ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid); + if (audit_buf != NULL) + netlbl_af6list_audit_addr(audit_buf, 1, + dev_name, + addr6, mask6); + break; + } +#endif /* IPv6 */ + default: + ret_val = -EINVAL; + } + if (ret_val == 0) + atomic_inc(&netlabel_mgmt_protocount); + +unlhsh_add_return: + rcu_read_unlock(); + if (audit_buf != NULL) { + if (security_secid_to_secctx(secid, + &secctx, + &secctx_len) == 0) { + audit_log_format(audit_buf, " sec_obj=%s", secctx); + security_release_secctx(secctx, secctx_len); + } + audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0); + audit_log_end(audit_buf); + } + return ret_val; +} + +/** + * netlbl_unlhsh_remove_addr4 - Remove an IPv4 address entry + * @net: network namespace + * @iface: interface entry + * @addr: IP address + * @mask: IP address mask + * @audit_info: NetLabel audit information + * + * Description: + * Remove an IP address entry from the unlabeled connection hash table. + * Returns zero on success, negative values on failure. + * + */ +static int netlbl_unlhsh_remove_addr4(struct net *net, + struct netlbl_unlhsh_iface *iface, + const struct in_addr *addr, + const struct in_addr *mask, + struct netlbl_audit *audit_info) +{ + struct netlbl_af4list *list_entry; + struct netlbl_unlhsh_addr4 *entry; + struct audit_buffer *audit_buf; + struct net_device *dev; + char *secctx; + u32 secctx_len; + + spin_lock(&netlbl_unlhsh_lock); + list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr, + &iface->addr4_list); + spin_unlock(&netlbl_unlhsh_lock); + if (list_entry != NULL) + entry = netlbl_unlhsh_addr4_entry(list_entry); + else + entry = NULL; + + audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL, + audit_info); + if (audit_buf != NULL) { + dev = dev_get_by_index(net, iface->ifindex); + netlbl_af4list_audit_addr(audit_buf, 1, + (dev != NULL ? dev->name : NULL), + addr->s_addr, mask->s_addr); + if (dev != NULL) + dev_put(dev); + if (entry != NULL && + security_secid_to_secctx(entry->secid, + &secctx, &secctx_len) == 0) { + audit_log_format(audit_buf, " sec_obj=%s", secctx); + security_release_secctx(secctx, secctx_len); + } + audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0); + audit_log_end(audit_buf); + } + + if (entry == NULL) + return -ENOENT; + + kfree_rcu(entry, rcu); + return 0; +} + +#if IS_ENABLED(CONFIG_IPV6) +/** + * netlbl_unlhsh_remove_addr6 - Remove an IPv6 address entry + * @net: network namespace + * @iface: interface entry + * @addr: IP address + * @mask: IP address mask + * @audit_info: NetLabel audit information + * + * Description: + * Remove an IP address entry from the unlabeled connection hash table. + * Returns zero on success, negative values on failure. + * + */ +static int netlbl_unlhsh_remove_addr6(struct net *net, + struct netlbl_unlhsh_iface *iface, + const struct in6_addr *addr, + const struct in6_addr *mask, + struct netlbl_audit *audit_info) +{ + struct netlbl_af6list *list_entry; + struct netlbl_unlhsh_addr6 *entry; + struct audit_buffer *audit_buf; + struct net_device *dev; + char *secctx; + u32 secctx_len; + + spin_lock(&netlbl_unlhsh_lock); + list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list); + spin_unlock(&netlbl_unlhsh_lock); + if (list_entry != NULL) + entry = netlbl_unlhsh_addr6_entry(list_entry); + else + entry = NULL; + + audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_STCDEL, + audit_info); + if (audit_buf != NULL) { + dev = dev_get_by_index(net, iface->ifindex); + netlbl_af6list_audit_addr(audit_buf, 1, + (dev != NULL ? dev->name : NULL), + addr, mask); + if (dev != NULL) + dev_put(dev); + if (entry != NULL && + security_secid_to_secctx(entry->secid, + &secctx, &secctx_len) == 0) { + audit_log_format(audit_buf, " sec_obj=%s", secctx); + security_release_secctx(secctx, secctx_len); + } + audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0); + audit_log_end(audit_buf); + } + + if (entry == NULL) + return -ENOENT; + + kfree_rcu(entry, rcu); + return 0; +} +#endif /* IPv6 */ + +/** + * netlbl_unlhsh_condremove_iface - Remove an interface entry + * @iface: the interface entry + * + * Description: + * Remove an interface entry from the unlabeled connection hash table if it is + * empty. An interface entry is considered to be empty if there are no + * address entries assigned to it. + * + */ +static void netlbl_unlhsh_condremove_iface(struct netlbl_unlhsh_iface *iface) +{ + struct netlbl_af4list *iter4; +#if IS_ENABLED(CONFIG_IPV6) + struct netlbl_af6list *iter6; +#endif /* IPv6 */ + + spin_lock(&netlbl_unlhsh_lock); + netlbl_af4list_foreach_rcu(iter4, &iface->addr4_list) + goto unlhsh_condremove_failure; +#if IS_ENABLED(CONFIG_IPV6) + netlbl_af6list_foreach_rcu(iter6, &iface->addr6_list) + goto unlhsh_condremove_failure; +#endif /* IPv6 */ + iface->valid = 0; + if (iface->ifindex > 0) + list_del_rcu(&iface->list); + else + RCU_INIT_POINTER(netlbl_unlhsh_def, NULL); + spin_unlock(&netlbl_unlhsh_lock); + + call_rcu(&iface->rcu, netlbl_unlhsh_free_iface); + return; + +unlhsh_condremove_failure: + spin_unlock(&netlbl_unlhsh_lock); +} + +/** + * netlbl_unlhsh_remove - Remove an entry from the unlabeled hash table + * @net: network namespace + * @dev_name: interface name + * @addr: IP address in network byte order + * @mask: address mask in network byte order + * @addr_len: length of address/mask (4 for IPv4, 16 for IPv6) + * @audit_info: NetLabel audit information + * + * Description: + * Removes and existing entry from the unlabeled connection hash table. + * Returns zero on success, negative values on failure. + * + */ +int netlbl_unlhsh_remove(struct net *net, + const char *dev_name, + const void *addr, + const void *mask, + u32 addr_len, + struct netlbl_audit *audit_info) +{ + int ret_val; + struct net_device *dev; + struct netlbl_unlhsh_iface *iface; + + if (addr_len != sizeof(struct in_addr) && + addr_len != sizeof(struct in6_addr)) + return -EINVAL; + + rcu_read_lock(); + if (dev_name != NULL) { + dev = dev_get_by_name_rcu(net, dev_name); + if (dev == NULL) { + ret_val = -ENODEV; + goto unlhsh_remove_return; + } + iface = netlbl_unlhsh_search_iface(dev->ifindex); + } else + iface = rcu_dereference(netlbl_unlhsh_def); + if (iface == NULL) { + ret_val = -ENOENT; + goto unlhsh_remove_return; + } + switch (addr_len) { + case sizeof(struct in_addr): + ret_val = netlbl_unlhsh_remove_addr4(net, + iface, addr, mask, + audit_info); + break; +#if IS_ENABLED(CONFIG_IPV6) + case sizeof(struct in6_addr): + ret_val = netlbl_unlhsh_remove_addr6(net, + iface, addr, mask, + audit_info); + break; +#endif /* IPv6 */ + default: + ret_val = -EINVAL; + } + if (ret_val == 0) { + netlbl_unlhsh_condremove_iface(iface); + atomic_dec(&netlabel_mgmt_protocount); + } + +unlhsh_remove_return: + rcu_read_unlock(); + return ret_val; +} + +/* + * General Helper Functions + */ + +/** + * netlbl_unlhsh_netdev_handler - Network device notification handler + * @this: notifier block + * @event: the event + * @ptr: the netdevice notifier info (cast to void) + * + * Description: + * Handle network device events, although at present all we care about is a + * network device going away. In the case of a device going away we clear any + * related entries from the unlabeled connection hash table. + * + */ +static int netlbl_unlhsh_netdev_handler(struct notifier_block *this, + unsigned long event, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct netlbl_unlhsh_iface *iface = NULL; + + if (!net_eq(dev_net(dev), &init_net)) + return NOTIFY_DONE; + + /* XXX - should this be a check for NETDEV_DOWN or _UNREGISTER? */ + if (event == NETDEV_DOWN) { + spin_lock(&netlbl_unlhsh_lock); + iface = netlbl_unlhsh_search_iface(dev->ifindex); + if (iface != NULL && iface->valid) { + iface->valid = 0; + list_del_rcu(&iface->list); + } else + iface = NULL; + spin_unlock(&netlbl_unlhsh_lock); + } + + if (iface != NULL) + call_rcu(&iface->rcu, netlbl_unlhsh_free_iface); + + return NOTIFY_DONE; +} + +/** + * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag + * @value: desired value + * @audit_info: NetLabel audit information + * + * Description: + * Set the value of the unlabeled accept flag to @value. + * + */ +static void netlbl_unlabel_acceptflg_set(u8 value, + struct netlbl_audit *audit_info) +{ + struct audit_buffer *audit_buf; + u8 old_val; + + old_val = netlabel_unlabel_acceptflg; + netlabel_unlabel_acceptflg = value; + audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW, + audit_info); + if (audit_buf != NULL) { + audit_log_format(audit_buf, + " unlbl_accept=%u old=%u", value, old_val); + audit_log_end(audit_buf); + } +} + +/** + * netlbl_unlabel_addrinfo_get - Get the IPv4/6 address information + * @info: the Generic NETLINK info block + * @addr: the IP address + * @mask: the IP address mask + * @len: the address length + * + * Description: + * Examine the Generic NETLINK message and extract the IP address information. + * Returns zero on success, negative values on failure. + * + */ +static int netlbl_unlabel_addrinfo_get(struct genl_info *info, + void **addr, + void **mask, + u32 *len) +{ + u32 addr_len; + + if (info->attrs[NLBL_UNLABEL_A_IPV4ADDR] && + info->attrs[NLBL_UNLABEL_A_IPV4MASK]) { + addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]); + if (addr_len != sizeof(struct in_addr) && + addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV4MASK])) + return -EINVAL; + *len = addr_len; + *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4ADDR]); + *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV4MASK]); + return 0; + } else if (info->attrs[NLBL_UNLABEL_A_IPV6ADDR]) { + addr_len = nla_len(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]); + if (addr_len != sizeof(struct in6_addr) && + addr_len != nla_len(info->attrs[NLBL_UNLABEL_A_IPV6MASK])) + return -EINVAL; + *len = addr_len; + *addr = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6ADDR]); + *mask = nla_data(info->attrs[NLBL_UNLABEL_A_IPV6MASK]); + return 0; + } + + return -EINVAL; +} + +/* + * NetLabel Command Handlers + */ + +/** + * netlbl_unlabel_accept - Handle an ACCEPT message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated ACCEPT message and set the accept flag accordingly. + * Returns zero on success, negative values on failure. + * + */ +static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info) +{ + u8 value; + struct netlbl_audit audit_info; + + if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) { + value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]); + if (value == 1 || value == 0) { + netlbl_netlink_auditinfo(skb, &audit_info); + netlbl_unlabel_acceptflg_set(value, &audit_info); + return 0; + } + } + + return -EINVAL; +} + +/** + * netlbl_unlabel_list - Handle a LIST message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated LIST message and respond with the current status. + * Returns zero on success, negative values on failure. + * + */ +static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info) +{ + int ret_val = -EINVAL; + struct sk_buff *ans_skb; + void *data; + + ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (ans_skb == NULL) + goto list_failure; + data = genlmsg_put_reply(ans_skb, info, &netlbl_unlabel_gnl_family, + 0, NLBL_UNLABEL_C_LIST); + if (data == NULL) { + ret_val = -ENOMEM; + goto list_failure; + } + + ret_val = nla_put_u8(ans_skb, + NLBL_UNLABEL_A_ACPTFLG, + netlabel_unlabel_acceptflg); + if (ret_val != 0) + goto list_failure; + + genlmsg_end(ans_skb, data); + return genlmsg_reply(ans_skb, info); + +list_failure: + kfree_skb(ans_skb); + return ret_val; +} + +/** + * netlbl_unlabel_staticadd - Handle a STATICADD message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated STATICADD message and add a new unlabeled + * connection entry to the hash table. Returns zero on success, negative + * values on failure. + * + */ +static int netlbl_unlabel_staticadd(struct sk_buff *skb, + struct genl_info *info) +{ + int ret_val; + char *dev_name; + void *addr; + void *mask; + u32 addr_len; + u32 secid; + struct netlbl_audit audit_info; + + /* Don't allow users to add both IPv4 and IPv6 addresses for a + * single entry. However, allow users to create two entries, one each + * for IPv4 and IPv4, with the same LSM security context which should + * achieve the same result. */ + if (!info->attrs[NLBL_UNLABEL_A_SECCTX] || + !info->attrs[NLBL_UNLABEL_A_IFACE] || + !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ + (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) + return -EINVAL; + + netlbl_netlink_auditinfo(skb, &audit_info); + + ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); + if (ret_val != 0) + return ret_val; + dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]); + ret_val = security_secctx_to_secid( + nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]), + nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]), + &secid); + if (ret_val != 0) + return ret_val; + + return netlbl_unlhsh_add(&init_net, + dev_name, addr, mask, addr_len, secid, + &audit_info); +} + +/** + * netlbl_unlabel_staticadddef - Handle a STATICADDDEF message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated STATICADDDEF message and add a new default + * unlabeled connection entry. Returns zero on success, negative values on + * failure. + * + */ +static int netlbl_unlabel_staticadddef(struct sk_buff *skb, + struct genl_info *info) +{ + int ret_val; + void *addr; + void *mask; + u32 addr_len; + u32 secid; + struct netlbl_audit audit_info; + + /* Don't allow users to add both IPv4 and IPv6 addresses for a + * single entry. However, allow users to create two entries, one each + * for IPv4 and IPv6, with the same LSM security context which should + * achieve the same result. */ + if (!info->attrs[NLBL_UNLABEL_A_SECCTX] || + !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ + (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) + return -EINVAL; + + netlbl_netlink_auditinfo(skb, &audit_info); + + ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); + if (ret_val != 0) + return ret_val; + ret_val = security_secctx_to_secid( + nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]), + nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]), + &secid); + if (ret_val != 0) + return ret_val; + + return netlbl_unlhsh_add(&init_net, + NULL, addr, mask, addr_len, secid, + &audit_info); +} + +/** + * netlbl_unlabel_staticremove - Handle a STATICREMOVE message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated STATICREMOVE message and remove the specified + * unlabeled connection entry. Returns zero on success, negative values on + * failure. + * + */ +static int netlbl_unlabel_staticremove(struct sk_buff *skb, + struct genl_info *info) +{ + int ret_val; + char *dev_name; + void *addr; + void *mask; + u32 addr_len; + struct netlbl_audit audit_info; + + /* See the note in netlbl_unlabel_staticadd() about not allowing both + * IPv4 and IPv6 in the same entry. */ + if (!info->attrs[NLBL_UNLABEL_A_IFACE] || + !((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ + (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) + return -EINVAL; + + netlbl_netlink_auditinfo(skb, &audit_info); + + ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); + if (ret_val != 0) + return ret_val; + dev_name = nla_data(info->attrs[NLBL_UNLABEL_A_IFACE]); + + return netlbl_unlhsh_remove(&init_net, + dev_name, addr, mask, addr_len, + &audit_info); +} + +/** + * netlbl_unlabel_staticremovedef - Handle a STATICREMOVEDEF message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated STATICREMOVEDEF message and remove the default + * unlabeled connection entry. Returns zero on success, negative values on + * failure. + * + */ +static int netlbl_unlabel_staticremovedef(struct sk_buff *skb, + struct genl_info *info) +{ + int ret_val; + void *addr; + void *mask; + u32 addr_len; + struct netlbl_audit audit_info; + + /* See the note in netlbl_unlabel_staticadd() about not allowing both + * IPv4 and IPv6 in the same entry. */ + if (!((!info->attrs[NLBL_UNLABEL_A_IPV4ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV4MASK]) ^ + (!info->attrs[NLBL_UNLABEL_A_IPV6ADDR] || + !info->attrs[NLBL_UNLABEL_A_IPV6MASK]))) + return -EINVAL; + + netlbl_netlink_auditinfo(skb, &audit_info); + + ret_val = netlbl_unlabel_addrinfo_get(info, &addr, &mask, &addr_len); + if (ret_val != 0) + return ret_val; + + return netlbl_unlhsh_remove(&init_net, + NULL, addr, mask, addr_len, + &audit_info); +} + + +/** + * netlbl_unlabel_staticlist_gen - Generate messages for STATICLIST[DEF] + * @cmd: command/message + * @iface: the interface entry + * @addr4: the IPv4 address entry + * @addr6: the IPv6 address entry + * @arg: the netlbl_unlhsh_walk_arg structure + * + * Description: + * This function is designed to be used to generate a response for a + * STATICLIST or STATICLISTDEF message. When called either @addr4 or @addr6 + * can be specified, not both, the other unspecified entry should be set to + * NULL by the caller. Returns the size of the message on success, negative + * values on failure. + * + */ +static int netlbl_unlabel_staticlist_gen(u32 cmd, + const struct netlbl_unlhsh_iface *iface, + const struct netlbl_unlhsh_addr4 *addr4, + const struct netlbl_unlhsh_addr6 *addr6, + void *arg) +{ + int ret_val = -ENOMEM; + struct netlbl_unlhsh_walk_arg *cb_arg = arg; + struct net_device *dev; + void *data; + u32 secid; + char *secctx; + u32 secctx_len; + + data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid, + cb_arg->seq, &netlbl_unlabel_gnl_family, + NLM_F_MULTI, cmd); + if (data == NULL) + goto list_cb_failure; + + if (iface->ifindex > 0) { + dev = dev_get_by_index(&init_net, iface->ifindex); + if (!dev) { + ret_val = -ENODEV; + goto list_cb_failure; + } + ret_val = nla_put_string(cb_arg->skb, + NLBL_UNLABEL_A_IFACE, dev->name); + dev_put(dev); + if (ret_val != 0) + goto list_cb_failure; + } + + if (addr4) { + struct in_addr addr_struct; + + addr_struct.s_addr = addr4->list.addr; + ret_val = nla_put_in_addr(cb_arg->skb, + NLBL_UNLABEL_A_IPV4ADDR, + addr_struct.s_addr); + if (ret_val != 0) + goto list_cb_failure; + + addr_struct.s_addr = addr4->list.mask; + ret_val = nla_put_in_addr(cb_arg->skb, + NLBL_UNLABEL_A_IPV4MASK, + addr_struct.s_addr); + if (ret_val != 0) + goto list_cb_failure; + + secid = addr4->secid; + } else { + ret_val = nla_put_in6_addr(cb_arg->skb, + NLBL_UNLABEL_A_IPV6ADDR, + &addr6->list.addr); + if (ret_val != 0) + goto list_cb_failure; + + ret_val = nla_put_in6_addr(cb_arg->skb, + NLBL_UNLABEL_A_IPV6MASK, + &addr6->list.mask); + if (ret_val != 0) + goto list_cb_failure; + + secid = addr6->secid; + } + + ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len); + if (ret_val != 0) + goto list_cb_failure; + ret_val = nla_put(cb_arg->skb, + NLBL_UNLABEL_A_SECCTX, + secctx_len, + secctx); + security_release_secctx(secctx, secctx_len); + if (ret_val != 0) + goto list_cb_failure; + + cb_arg->seq++; + genlmsg_end(cb_arg->skb, data); + return 0; + +list_cb_failure: + genlmsg_cancel(cb_arg->skb, data); + return ret_val; +} + +/** + * netlbl_unlabel_staticlist - Handle a STATICLIST message + * @skb: the NETLINK buffer + * @cb: the NETLINK callback + * + * Description: + * Process a user generated STATICLIST message and dump the unlabeled + * connection hash table in a form suitable for use in a kernel generated + * STATICLIST message. Returns the length of @skb. + * + */ +static int netlbl_unlabel_staticlist(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct netlbl_unlhsh_walk_arg cb_arg; + u32 skip_bkt = cb->args[0]; + u32 skip_chain = cb->args[1]; + u32 skip_addr4 = cb->args[2]; + u32 iter_bkt, iter_chain = 0, iter_addr4 = 0, iter_addr6 = 0; + struct netlbl_unlhsh_iface *iface; + struct list_head *iter_list; + struct netlbl_af4list *addr4; +#if IS_ENABLED(CONFIG_IPV6) + u32 skip_addr6 = cb->args[3]; + struct netlbl_af6list *addr6; +#endif + + cb_arg.nl_cb = cb; + cb_arg.skb = skb; + cb_arg.seq = cb->nlh->nlmsg_seq; + + rcu_read_lock(); + for (iter_bkt = skip_bkt; + iter_bkt < rcu_dereference(netlbl_unlhsh)->size; + iter_bkt++) { + iter_list = &rcu_dereference(netlbl_unlhsh)->tbl[iter_bkt]; + list_for_each_entry_rcu(iface, iter_list, list) { + if (!iface->valid || + iter_chain++ < skip_chain) + continue; + netlbl_af4list_foreach_rcu(addr4, + &iface->addr4_list) { + if (iter_addr4++ < skip_addr4) + continue; + if (netlbl_unlabel_staticlist_gen( + NLBL_UNLABEL_C_STATICLIST, + iface, + netlbl_unlhsh_addr4_entry(addr4), + NULL, + &cb_arg) < 0) { + iter_addr4--; + iter_chain--; + goto unlabel_staticlist_return; + } + } + iter_addr4 = 0; + skip_addr4 = 0; +#if IS_ENABLED(CONFIG_IPV6) + netlbl_af6list_foreach_rcu(addr6, + &iface->addr6_list) { + if (iter_addr6++ < skip_addr6) + continue; + if (netlbl_unlabel_staticlist_gen( + NLBL_UNLABEL_C_STATICLIST, + iface, + NULL, + netlbl_unlhsh_addr6_entry(addr6), + &cb_arg) < 0) { + iter_addr6--; + iter_chain--; + goto unlabel_staticlist_return; + } + } + iter_addr6 = 0; + skip_addr6 = 0; +#endif /* IPv6 */ + } + iter_chain = 0; + skip_chain = 0; + } + +unlabel_staticlist_return: + rcu_read_unlock(); + cb->args[0] = iter_bkt; + cb->args[1] = iter_chain; + cb->args[2] = iter_addr4; + cb->args[3] = iter_addr6; + return skb->len; +} + +/** + * netlbl_unlabel_staticlistdef - Handle a STATICLISTDEF message + * @skb: the NETLINK buffer + * @cb: the NETLINK callback + * + * Description: + * Process a user generated STATICLISTDEF message and dump the default + * unlabeled connection entry in a form suitable for use in a kernel generated + * STATICLISTDEF message. Returns the length of @skb. + * + */ +static int netlbl_unlabel_staticlistdef(struct sk_buff *skb, + struct netlink_callback *cb) +{ + struct netlbl_unlhsh_walk_arg cb_arg; + struct netlbl_unlhsh_iface *iface; + u32 iter_addr4 = 0, iter_addr6 = 0; + struct netlbl_af4list *addr4; +#if IS_ENABLED(CONFIG_IPV6) + struct netlbl_af6list *addr6; +#endif + + cb_arg.nl_cb = cb; + cb_arg.skb = skb; + cb_arg.seq = cb->nlh->nlmsg_seq; + + rcu_read_lock(); + iface = rcu_dereference(netlbl_unlhsh_def); + if (iface == NULL || !iface->valid) + goto unlabel_staticlistdef_return; + + netlbl_af4list_foreach_rcu(addr4, &iface->addr4_list) { + if (iter_addr4++ < cb->args[0]) + continue; + if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF, + iface, + netlbl_unlhsh_addr4_entry(addr4), + NULL, + &cb_arg) < 0) { + iter_addr4--; + goto unlabel_staticlistdef_return; + } + } +#if IS_ENABLED(CONFIG_IPV6) + netlbl_af6list_foreach_rcu(addr6, &iface->addr6_list) { + if (iter_addr6++ < cb->args[1]) + continue; + if (netlbl_unlabel_staticlist_gen(NLBL_UNLABEL_C_STATICLISTDEF, + iface, + NULL, + netlbl_unlhsh_addr6_entry(addr6), + &cb_arg) < 0) { + iter_addr6--; + goto unlabel_staticlistdef_return; + } + } +#endif /* IPv6 */ + +unlabel_staticlistdef_return: + rcu_read_unlock(); + cb->args[0] = iter_addr4; + cb->args[1] = iter_addr6; + return skb->len; +} + +/* + * NetLabel Generic NETLINK Command Definitions + */ + +static const struct genl_ops netlbl_unlabel_genl_ops[] = { + { + .cmd = NLBL_UNLABEL_C_STATICADD, + .flags = GENL_ADMIN_PERM, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_staticadd, + .dumpit = NULL, + }, + { + .cmd = NLBL_UNLABEL_C_STATICREMOVE, + .flags = GENL_ADMIN_PERM, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_staticremove, + .dumpit = NULL, + }, + { + .cmd = NLBL_UNLABEL_C_STATICLIST, + .flags = 0, + .policy = netlbl_unlabel_genl_policy, + .doit = NULL, + .dumpit = netlbl_unlabel_staticlist, + }, + { + .cmd = NLBL_UNLABEL_C_STATICADDDEF, + .flags = GENL_ADMIN_PERM, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_staticadddef, + .dumpit = NULL, + }, + { + .cmd = NLBL_UNLABEL_C_STATICREMOVEDEF, + .flags = GENL_ADMIN_PERM, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_staticremovedef, + .dumpit = NULL, + }, + { + .cmd = NLBL_UNLABEL_C_STATICLISTDEF, + .flags = 0, + .policy = netlbl_unlabel_genl_policy, + .doit = NULL, + .dumpit = netlbl_unlabel_staticlistdef, + }, + { + .cmd = NLBL_UNLABEL_C_ACCEPT, + .flags = GENL_ADMIN_PERM, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_accept, + .dumpit = NULL, + }, + { + .cmd = NLBL_UNLABEL_C_LIST, + .flags = 0, + .policy = netlbl_unlabel_genl_policy, + .doit = netlbl_unlabel_list, + .dumpit = NULL, + }, +}; + +static struct genl_family netlbl_unlabel_gnl_family __ro_after_init = { + .hdrsize = 0, + .name = NETLBL_NLTYPE_UNLABELED_NAME, + .version = NETLBL_PROTO_VERSION, + .maxattr = NLBL_UNLABEL_A_MAX, + .module = THIS_MODULE, + .ops = netlbl_unlabel_genl_ops, + .n_ops = ARRAY_SIZE(netlbl_unlabel_genl_ops), +}; + +/* + * NetLabel Generic NETLINK Protocol Functions + */ + +/** + * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component + * + * Description: + * Register the unlabeled packet NetLabel component with the Generic NETLINK + * mechanism. Returns zero on success, negative values on failure. + * + */ +int __init netlbl_unlabel_genl_init(void) +{ + return genl_register_family(&netlbl_unlabel_gnl_family); +} + +/* + * NetLabel KAPI Hooks + */ + +static struct notifier_block netlbl_unlhsh_netdev_notifier = { + .notifier_call = netlbl_unlhsh_netdev_handler, +}; + +/** + * netlbl_unlabel_init - Initialize the unlabeled connection hash table + * @size: the number of bits to use for the hash buckets + * + * Description: + * Initializes the unlabeled connection hash table and registers a network + * device notification handler. This function should only be called by the + * NetLabel subsystem itself during initialization. Returns zero on success, + * non-zero values on error. + * + */ +int __init netlbl_unlabel_init(u32 size) +{ + u32 iter; + struct netlbl_unlhsh_tbl *hsh_tbl; + + if (size == 0) + return -EINVAL; + + hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL); + if (hsh_tbl == NULL) + return -ENOMEM; + hsh_tbl->size = 1 << size; + hsh_tbl->tbl = kcalloc(hsh_tbl->size, + sizeof(struct list_head), + GFP_KERNEL); + if (hsh_tbl->tbl == NULL) { + kfree(hsh_tbl); + return -ENOMEM; + } + for (iter = 0; iter < hsh_tbl->size; iter++) + INIT_LIST_HEAD(&hsh_tbl->tbl[iter]); + + spin_lock(&netlbl_unlhsh_lock); + rcu_assign_pointer(netlbl_unlhsh, hsh_tbl); + spin_unlock(&netlbl_unlhsh_lock); + + register_netdevice_notifier(&netlbl_unlhsh_netdev_notifier); + + return 0; +} + +/** + * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet + * @skb: the packet + * @family: protocol family + * @secattr: the security attributes + * + * Description: + * Determine the security attributes, if any, for an unlabled packet and return + * them in @secattr. Returns zero on success and negative values on failure. + * + */ +int netlbl_unlabel_getattr(const struct sk_buff *skb, + u16 family, + struct netlbl_lsm_secattr *secattr) +{ + struct netlbl_unlhsh_iface *iface; + + rcu_read_lock(); + iface = netlbl_unlhsh_search_iface(skb->skb_iif); + if (iface == NULL) + iface = rcu_dereference(netlbl_unlhsh_def); + if (iface == NULL || !iface->valid) + goto unlabel_getattr_nolabel; + +#if IS_ENABLED(CONFIG_IPV6) + /* When resolving a fallback label, check the sk_buff version as + * it is possible (e.g. SCTP) to have family = PF_INET6 while + * receiving ip_hdr(skb)->version = 4. + */ + if (family == PF_INET6 && ip_hdr(skb)->version == 4) + family = PF_INET; +#endif /* IPv6 */ + + switch (family) { + case PF_INET: { + struct iphdr *hdr4; + struct netlbl_af4list *addr4; + + hdr4 = ip_hdr(skb); + addr4 = netlbl_af4list_search(hdr4->saddr, + &iface->addr4_list); + if (addr4 == NULL) + goto unlabel_getattr_nolabel; + secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid; + break; + } +#if IS_ENABLED(CONFIG_IPV6) + case PF_INET6: { + struct ipv6hdr *hdr6; + struct netlbl_af6list *addr6; + + hdr6 = ipv6_hdr(skb); + addr6 = netlbl_af6list_search(&hdr6->saddr, + &iface->addr6_list); + if (addr6 == NULL) + goto unlabel_getattr_nolabel; + secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid; + break; + } +#endif /* IPv6 */ + default: + goto unlabel_getattr_nolabel; + } + rcu_read_unlock(); + + secattr->flags |= NETLBL_SECATTR_SECID; + secattr->type = NETLBL_NLTYPE_UNLABELED; + return 0; + +unlabel_getattr_nolabel: + rcu_read_unlock(); + if (netlabel_unlabel_acceptflg == 0) + return -ENOMSG; + secattr->type = NETLBL_NLTYPE_UNLABELED; + return 0; +} + +/** + * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets + * + * Description: + * Set the default NetLabel configuration to allow incoming unlabeled packets + * and to send unlabeled network traffic by default. + * + */ +int __init netlbl_unlabel_defconf(void) +{ + int ret_val; + struct netlbl_dom_map *entry; + struct netlbl_audit audit_info; + + /* Only the kernel is allowed to call this function and the only time + * it is called is at bootup before the audit subsystem is reporting + * messages so don't worry to much about these values. */ + security_task_getsecid(current, &audit_info.secid); + audit_info.loginuid = GLOBAL_ROOT_UID; + audit_info.sessionid = 0; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (entry == NULL) + return -ENOMEM; + entry->family = AF_UNSPEC; + entry->def.type = NETLBL_NLTYPE_UNLABELED; + ret_val = netlbl_domhsh_add_default(entry, &audit_info); + if (ret_val != 0) + return ret_val; + + netlbl_unlabel_acceptflg_set(1, &audit_info); + + return 0; +} |