path: root/net/netlabel/netlabel_kapi.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * NetLabel Kernel API
 *
 * This file defines the kernel API 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
 */

#include <linux/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/audit.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.h>
#include <net/calipso.h>
#include <asm/bug.h>
#include <linux/atomic.h>

#include "netlabel_domainhash.h"
#include "netlabel_unlabeled.h"
#include "netlabel_cipso_v4.h"
#include "netlabel_calipso.h"
#include "netlabel_user.h"
#include "netlabel_mgmt.h"
#include "netlabel_addrlist.h"

/*
 * Configuration Functions
 */

/**
 * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping
 * @domain: the domain mapping to remove
 * @family: address family
 * @addr: IP address
 * @mask: IP address mask
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Removes a NetLabel/LSM domain mapping.  A @domain value of NULL causes the
 * default domain mapping to be removed.  Returns zero on success, negative
 * values on failure.
 *
 */
int netlbl_cfg_map_del(const char *domain,
		       u16 family,
		       const void *addr,
		       const void *mask,
		       struct netlbl_audit *audit_info)
{
	if (addr == NULL && mask == NULL) {
		return netlbl_domhsh_remove(domain, family, audit_info);
	} else if (addr != NULL && mask != NULL) {
		switch (family) {
		case AF_INET:
			return netlbl_domhsh_remove_af4(domain, addr, mask,
							audit_info);
#if IS_ENABLED(CONFIG_IPV6)
		case AF_INET6:
			return netlbl_domhsh_remove_af6(domain, addr, mask,
							audit_info);
#endif /* IPv6 */
		default:
			return -EPFNOSUPPORT;
		}
	} else
		return -EINVAL;
}

/**
 * netlbl_cfg_unlbl_map_add - Add a new unlabeled mapping
 * @domain: the domain mapping to add
 * @family: address family
 * @addr: IP address
 * @mask: IP address mask
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Adds a new unlabeled NetLabel/LSM domain mapping.  A @domain value of NULL
 * causes a new default domain mapping to be added.  Returns zero on success,
 * negative values on failure.
 *
 */
int netlbl_cfg_unlbl_map_add(const char *domain,
			     u16 family,
			     const void *addr,
			     const void *mask,
			     struct netlbl_audit *audit_info)
{
	int ret_val = -ENOMEM;
	struct netlbl_dom_map *entry;
	struct netlbl_domaddr_map *addrmap = NULL;
	struct netlbl_domaddr4_map *map4 = NULL;
	struct netlbl_domaddr6_map *map6 = NULL;

	entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
	if (entry == NULL)
		return -ENOMEM;
	if (domain != NULL) {
		entry->domain = kstrdup(domain, GFP_ATOMIC);
		if (entry->domain == NULL)
			goto cfg_unlbl_map_add_failure;
	}
	entry->family = family;

	if (addr == NULL && mask == NULL)
		entry->def.type = NETLBL_NLTYPE_UNLABELED;
	else if (addr != NULL && mask != NULL) {
		addrmap = kzalloc(sizeof(*addrmap), GFP_ATOMIC);
		if (addrmap == NULL)
			goto cfg_unlbl_map_add_failure;
		INIT_LIST_HEAD(&addrmap->list4);
		INIT_LIST_HEAD(&addrmap->list6);

		switch (family) {
		case AF_INET: {
			const struct in_addr *addr4 = addr;
			const struct in_addr *mask4 = mask;
			map4 = kzalloc(sizeof(*map4), GFP_ATOMIC);
			if (map4 == NULL)
				goto cfg_unlbl_map_add_failure;
			map4->def.type = NETLBL_NLTYPE_UNLABELED;
			map4->list.addr = addr4->s_addr & mask4->s_addr;
			map4->list.mask = mask4->s_addr;
			map4->list.valid = 1;
			ret_val = netlbl_af4list_add(&map4->list,
						     &addrmap->list4);
			if (ret_val != 0)
				goto cfg_unlbl_map_add_failure;
			break;
			}
#if IS_ENABLED(CONFIG_IPV6)
		case AF_INET6: {
			const struct in6_addr *addr6 = addr;
			const struct in6_addr *mask6 = mask;
			map6 = kzalloc(sizeof(*map6), GFP_ATOMIC);
			if (map6 == NULL)
				goto cfg_unlbl_map_add_failure;
			map6->def.type = NETLBL_NLTYPE_UNLABELED;
			map6->list.addr = *addr6;
			map6->list.addr.s6_addr32[0] &= mask6->s6_addr32[0];
			map6->list.addr.s6_addr32[1] &= mask6->s6_addr32[1];
			map6->list.addr.s6_addr32[2] &= mask6->s6_addr32[2];
			map6->list.addr.s6_addr32[3] &= mask6->s6_addr32[3];
			map6->list.mask = *mask6;
			map6->list.valid = 1;
			ret_val = netlbl_af6list_add(&map6->list,
						     &addrmap->list6);
			if (ret_val != 0)
				goto cfg_unlbl_map_add_failure;
			break;
			}
#endif /* IPv6 */
		default:
			goto cfg_unlbl_map_add_failure;
		}

		entry->def.addrsel = addrmap;
		entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
	} else {
		ret_val = -EINVAL;
		goto cfg_unlbl_map_add_failure;
	}

	ret_val = netlbl_domhsh_add(entry, audit_info);
	if (ret_val != 0)
		goto cfg_unlbl_map_add_failure;

	return 0;

cfg_unlbl_map_add_failure:
	kfree(entry->domain);
	kfree(entry);
	kfree(addrmap);
	kfree(map4);
	kfree(map6);
	return ret_val;
}


/**
 * netlbl_cfg_unlbl_static_add - Adds a new static label
 * @net: network namespace
 * @dev_name: interface name
 * @addr: IP address in network byte order (struct in[6]_addr)
 * @mask: address mask in network byte order (struct in[6]_addr)
 * @family: address family
 * @secid: LSM secid value for the entry
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Adds a new NetLabel static label to be used when protocol provided labels
 * are not present on incoming traffic.  If @dev_name is NULL then the default
 * interface will be used.  Returns zero on success, negative values on failure.
 *
 */
int netlbl_cfg_unlbl_static_add(struct net *net,
				const char *dev_name,
				const void *addr,
				const void *mask,
				u16 family,
				u32 secid,
				struct netlbl_audit *audit_info)
{
	u32 addr_len;

	switch (family) {
	case AF_INET:
		addr_len = sizeof(struct in_addr);
		break;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		addr_len = sizeof(struct in6_addr);
		break;
#endif /* IPv6 */
	default:
		return -EPFNOSUPPORT;
	}

	return netlbl_unlhsh_add(net,
				 dev_name, addr, mask, addr_len,
				 secid, audit_info);
}

/**
 * netlbl_cfg_unlbl_static_del - Removes an existing static label
 * @net: network namespace
 * @dev_name: interface name
 * @addr: IP address in network byte order (struct in[6]_addr)
 * @mask: address mask in network byte order (struct in[6]_addr)
 * @family: address family
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Removes an existing NetLabel static label used when protocol provided labels
 * are not present on incoming traffic.  If @dev_name is NULL then the default
 * interface will be used.  Retur