--- /dev/null
+/*
+ * 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.moore@hp.com>
+ *
+ */
+
+/*
+ * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <net/ip.h>
+#include <net/netlabel.h>
+#include <net/cipso_ipv4.h>
+#include <asm/bug.h>
+
+#include "netlabel_domainhash.h"
+#include "netlabel_unlabeled.h"
+#include "netlabel_user.h"
+
+/*
+ * Security Attribute Functions
+ */
+
+/**
+ * netlbl_secattr_catmap_walk - Walk a LSM secattr catmap looking for a bit
+ * @catmap: the category bitmap
+ * @offset: the offset to start searching at, in bits
+ *
+ * Description:
+ * This function walks a LSM secattr category bitmap starting at @offset and
+ * returns the spot of the first set bit or -ENOENT if no bits are set.
+ *
+ */
+int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
+ u32 offset)
+{
+ struct netlbl_lsm_secattr_catmap *iter = catmap;
+ u32 node_idx;
+ u32 node_bit;
+ NETLBL_CATMAP_MAPTYPE bitmap;
+
+ if (offset > iter->startbit) {
+ while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+ iter = iter->next;
+ if (iter == NULL)
+ return -ENOENT;
+ }
+ node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+ node_bit = offset - iter->startbit -
+ (NETLBL_CATMAP_MAPSIZE * node_idx);
+ } else {
+ node_idx = 0;
+ node_bit = 0;
+ }
+ bitmap = iter->bitmap[node_idx] >> node_bit;
+
+ for (;;) {
+ if (bitmap != 0) {
+ while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
+ bitmap >>= 1;
+ node_bit++;
+ }
+ return iter->startbit +
+ (NETLBL_CATMAP_MAPSIZE * node_idx) + node_bit;
+ }
+ if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
+ if (iter->next != NULL) {
+ iter = iter->next;
+ node_idx = 0;
+ } else
+ return -ENOENT;
+ }
+ bitmap = iter->bitmap[node_idx];
+ node_bit = 0;
+ }
+
+ return -ENOENT;
+}
+
+/**
+ * netlbl_secattr_catmap_walk_rng - Find the end of a string of set bits
+ * @catmap: the category bitmap
+ * @offset: the offset to start searching at, in bits
+ *
+ * Description:
+ * This function walks a LSM secattr category bitmap starting at @offset and
+ * returns the spot of the first cleared bit or -ENOENT if the offset is past
+ * the end of the bitmap.
+ *
+ */
+int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
+ u32 offset)
+{
+ struct netlbl_lsm_secattr_catmap *iter = catmap;
+ u32 node_idx;
+ u32 node_bit;
+ NETLBL_CATMAP_MAPTYPE bitmask;
+ NETLBL_CATMAP_MAPTYPE bitmap;
+
+ if (offset > iter->startbit) {
+ while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+ iter = iter->next;
+ if (iter == NULL)
+ return -ENOENT;
+ }
+ node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+ node_bit = offset - iter->startbit -
+ (NETLBL_CATMAP_MAPSIZE * node_idx);
+ } else {
+ node_idx = 0;
+ node_bit = 0;
+ }
+ bitmask = NETLBL_CATMAP_BIT << node_bit;
+
+ for (;;) {
+ bitmap = iter->bitmap[node_idx];
+ while (bitmask != 0 && (bitmap & bitmask) != 0) {
+ bitmask <<= 1;
+ node_bit++;
+ }
+
+ if (bitmask != 0)
+ return iter->startbit +
+ (NETLBL_CATMAP_MAPSIZE * node_idx) +
+ node_bit - 1;
+ else if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
+ if (iter->next == NULL)
+ return iter->startbit + NETLBL_CATMAP_SIZE - 1;
+ iter = iter->next;
+ node_idx = 0;
+ }
+ bitmask = NETLBL_CATMAP_BIT;
+ node_bit = 0;
+ }
+
+ return -ENOENT;
+}
+
+/**
+ * netlbl_secattr_catmap_setbit - Set a bit in a LSM secattr catmap
+ * @catmap: the category bitmap
+ * @bit: the bit to set
+ * @flags: memory allocation flags
+ *
+ * Description:
+ * Set the bit specified by @bit in @catmap. Returns zero on success,
+ * negative values on failure.
+ *
+ */
+int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
+ u32 bit,
+ gfp_t flags)
+{
+ struct netlbl_lsm_secattr_catmap *iter = catmap;
+ u32 node_bit;
+ u32 node_idx;
+
+ while (iter->next != NULL &&
+ bit >= (iter->startbit + NETLBL_CATMAP_SIZE))
+ iter = iter->next;
+ if (bit >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+ iter->next = netlbl_secattr_catmap_alloc(flags);
+ if (iter->next == NULL)
+ return -ENOMEM;
+ iter = iter->next;
+ iter->startbit = bit & ~(NETLBL_CATMAP_SIZE - 1);
+ }
+
+ /* gcc always rounds to zero when doing integer division */
+ node_idx = (bit - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+ node_bit = bit - iter->startbit - (NETLBL_CATMAP_MAPSIZE * node_idx);
+ iter->bitmap[node_idx] |= NETLBL_CATMAP_BIT << node_bit;
+
+ return 0;
+}
+
+/**
+ * netlbl_secattr_catmap_setrng - Set a range of bits in a LSM secattr catmap
+ * @catmap: the category bitmap
+ * @start: the starting bit
+ * @end: the last bit in the string
+ * @flags: memory allocation flags
+ *
+ * Description:
+ * Set a range of bits, starting at @start and ending with @end. Returns zero
+ * on success, negative values on failure.
+ *
+ */
+int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
+ u32 start,
+ u32 end,
+ gfp_t flags)
+{
+ int ret_val = 0;
+ struct netlbl_lsm_secattr_catmap *iter = catmap;
+ u32 iter_max_spot;
+ u32 spot;
+
+ /* XXX - This could probably be made a bit faster by combining writes
+ * to the catmap instead of setting a single bit each time, but for
+ * right now skipping to the start of the range in the catmap should
+ * be a nice improvement over calling the individual setbit function
+ * repeatedly from a loop. */
+
+ while (iter->next != NULL &&
+ start >= (iter->startbit + NETLBL_CATMAP_SIZE))
+ iter = iter->next;
+ iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
+
+ for (spot = start; spot <= end && ret_val == 0; spot++) {
+ if (spot >= iter_max_spot && iter->next != NULL) {
+ iter = iter->next;
+ iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
+ }
+ ret_val = netlbl_secattr_catmap_setbit(iter, spot, GFP_ATOMIC);
+ }
+
+ return ret_val;
+}
+
+/*
+ * LSM Functions
+ */
+
+/**
+ * netlbl_socket_setattr - Label a socket using the correct protocol
+ * @sock: the socket to label
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Attach the correct label to the given socket using the security attributes
+ * specified in @secattr. This function requires exclusive access to
+ * @sock->sk, which means it either needs to be in the process of being
+ * created or locked via lock_sock(sock->sk). Returns zero on success,
+ * negative values on failure.
+ *
+ */
+int netlbl_socket_setattr(const struct socket *sock,
+ const struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val = -ENOENT;
+ struct netlbl_dom_map *dom_entry;
+
+ if ((secattr->flags & NETLBL_SECATTR_DOMAIN) == 0)
+ return -ENOENT;
+
+ rcu_read_lock();
+ dom_entry = netlbl_domhsh_getentry(secattr->domain);
+ if (dom_entry == NULL)
+ goto socket_setattr_return;
+ switch (dom_entry->type) {
+ case NETLBL_NLTYPE_CIPSOV4:
+ ret_val = cipso_v4_socket_setattr(sock,
+ dom_entry->type_def.cipsov4,
+ secattr);
+ break;
+ case NETLBL_NLTYPE_UNLABELED:
+ ret_val = 0;
+ break;
+ default:
+ ret_val = -ENOENT;
+ }
+
+socket_setattr_return:
+ rcu_read_unlock();
+ return ret_val;
+}
+
+/**
+ * netlbl_sock_getattr - Determine the security attributes of a sock
+ * @sk: the sock
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Examines the given sock to see any NetLabel style labeling has been
+ * applied to the sock, if so it parses the socket label and returns the
+ * security attributes in @secattr. Returns zero on success, negative values
+ * on failure.
+ *
+ */
+int netlbl_sock_getattr(struct sock *sk, struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val;
+
+ ret_val = cipso_v4_sock_getattr(sk, secattr);
+ if (ret_val == 0)
+ return 0;
+
+ return netlbl_unlabel_getattr(secattr);
+}
+
+/**
+ * netlbl_socket_getattr - Determine the security attributes of a socket
+ * @sock: the socket
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Examines the given socket to see any NetLabel style labeling has been
+ * applied to the socket, if so it parses the socket label and returns the
+ * security attributes in @secattr. Returns zero on success, negative values
+ * on failure.
+ *
+ */
+int netlbl_socket_getattr(const struct socket *sock,
+ struct netlbl_lsm_secattr *secattr)
+{
+ int ret_val;
+
+ ret_val = cipso_v4_socket_getattr(sock, secattr);
+ if (ret_val == 0)
+ return 0;
+
+ return netlbl_unlabel_getattr(secattr);
+}
+
+/**
+ * netlbl_skbuff_getattr - Determine the security attributes of a packet
+ * @skb: the packet
+ * @secattr: the security attributes
+ *
+ * Description:
+ * Examines the given packet to see if a recognized form of packet labeling
+ * is present, if so it parses the packet label and returns the security
+ * attributes in @secattr. Returns zero on success, negative values on
+ * failure.
+ *
+ */
+int netlbl_skbuff_getattr(const struct sk_buff *skb,
+ struct netlbl_lsm_secattr *secattr)
+{
+ if (CIPSO_V4_OPTEXIST(skb) &&
+ cipso_v4_skbuff_getattr(skb, secattr) == 0)
+ return 0;
+
+ return netlbl_unlabel_getattr(secattr);
+}
+
+/**
+ * netlbl_skbuff_err - Handle a LSM error on a sk_buff
+ * @skb: the packet
+ * @error: the error code
+ *
+ * Description:
+ * Deal with a LSM problem when handling the packet in @skb, typically this is
+ * a permission denied problem (-EACCES). The correct action is determined
+ * according to the packet's labeling protocol.
+ *
+ */
+void netlbl_skbuff_err(struct sk_buff *skb, int error)
+{
+ if (CIPSO_V4_OPTEXIST(skb))
+ cipso_v4_error(skb, error, 0);
+}
+
+/**
+ * netlbl_cache_invalidate - Invalidate all of the NetLabel protocol caches
+ *
+ * Description:
+ * For all of the NetLabel protocols that support some form of label mapping
+ * cache, invalidate the cache. Returns zero on success, negative values on
+ * error.
+ *
+ */
+void netlbl_cache_invalidate(void)
+{
+ cipso_v4_cache_invalidate();
+}
+
+/**
+ * netlbl_cache_add - Add an entry to a NetLabel protocol cache
+ * @skb: the packet
+ * @secattr: the packet's security attributes
+ *
+ * Description:
+ * Add the LSM security attributes for the given packet to the underlying
+ * NetLabel protocol's label mapping cache. Returns zero on success, negative
+ * values on error.
+ *
+ */
+int netlbl_cache_add(const struct sk_buff *skb,
+ const struct netlbl_lsm_secattr *secattr)
+{
+ if ((secattr->flags & NETLBL_SECATTR_CACHE) == 0)
+ return -ENOMSG;
+
+ if (CIPSO_V4_OPTEXIST(skb))
+ return cipso_v4_cache_add(skb, secattr);
+
+ return -ENOMSG;
+}
+
+/*
+ * Setup Functions
+ */
+
+/**
+ * netlbl_init - Initialize NetLabel
+ *
+ * Description:
+ * Perform the required NetLabel initialization before first use.
+ *
+ */
+static int __init netlbl_init(void)
+{
+ int ret_val;
+
+ printk(KERN_INFO "NetLabel: Initializing\n");
+ printk(KERN_INFO "NetLabel: domain hash size = %u\n",
+ (1 << NETLBL_DOMHSH_BITSIZE));
+ printk(KERN_INFO "NetLabel: protocols ="
+ " UNLABELED"
+ " CIPSOv4"
+ "\n");
+
+ ret_val = netlbl_domhsh_init(NETLBL_DOMHSH_BITSIZE);
+ if (ret_val != 0)
+ goto init_failure;
+
+ ret_val = netlbl_netlink_init();
+ if (ret_val != 0)
+ goto init_failure;
+
+ ret_val = netlbl_unlabel_defconf();
+ if (ret_val != 0)
+ goto init_failure;
+ printk(KERN_INFO "NetLabel: unlabeled traffic allowed by default\n");
+
+ return 0;
+
+init_failure:
+ panic("NetLabel: failed to initialize properly (%d)\n", ret_val);
+}
+
+subsys_initcall(netlbl_init);
git://git.onelab.eu / linux-2.6.git / blobdiff