| /* |
| * 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 <linux/audit.h> |
| #include <net/ip.h> |
| #include <net/netlabel.h> |
| #include <net/cipso_ipv4.h> |
| #include <asm/bug.h> |
| #include <asm/atomic.h> |
| |
| #include "netlabel_domainhash.h" |
| #include "netlabel_unlabeled.h" |
| #include "netlabel_cipso_v4.h" |
| #include "netlabel_user.h" |
| #include "netlabel_mgmt.h" |
| |
| /* |
| * Configuration Functions |
| */ |
| |
| /** |
| * netlbl_cfg_map_del - Remove a NetLabel/LSM domain mapping |
| * @domain: the domain mapping to remove |
| * @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, struct netlbl_audit *audit_info) |
| { |
| return netlbl_domhsh_remove(domain, audit_info); |
| } |
| |
| /** |
| * netlbl_cfg_unlbl_add_map - Add an unlabeled NetLabel/LSM domain mapping |
| * @domain: the domain mapping to add |
| * @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_add_map(const char *domain, |
| struct netlbl_audit *audit_info) |
| { |
| int ret_val = -ENOMEM; |
| struct netlbl_dom_map *entry; |
| |
| entry = kzalloc(sizeof(*entry), GFP_ATOMIC); |
| if (entry == NULL) |
| goto cfg_unlbl_add_map_failure; |
| if (domain != NULL) { |
| entry->domain = kstrdup(domain, GFP_ATOMIC); |
| if (entry->domain == NULL) |
| goto cfg_unlbl_add_map_failure; |
| } |
| entry->type = NETLBL_NLTYPE_UNLABELED; |
| |
| ret_val = netlbl_domhsh_add(entry, audit_info); |
| if (ret_val != 0) |
| goto cfg_unlbl_add_map_failure; |
| |
| return 0; |
| |
| cfg_unlbl_add_map_failure: |
| if (entry != NULL) |
| kfree(entry->domain); |
| kfree(entry); |
| return ret_val; |
| } |
| |
| /** |
| * netlbl_cfg_cipsov4_add - Add a new CIPSOv4 DOI definition |
| * @doi_def: the DOI definition |
| * @audit_info: NetLabel audit information |
| * |
| * Description: |
| * Add a new CIPSOv4 DOI definition to the NetLabel subsystem. Returns zero on |
| * success, negative values on failure. |
| * |
| */ |
| int netlbl_cfg_cipsov4_add(struct cipso_v4_doi *doi_def, |
| struct netlbl_audit *audit_info) |
| { |
| int ret_val; |
| const char *type_str; |
| struct audit_buffer *audit_buf; |
| |
| ret_val = cipso_v4_doi_add(doi_def); |
| |
| audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD, |
| audit_info); |
| if (audit_buf != NULL) { |
| switch (doi_def->type) { |
| case CIPSO_V4_MAP_STD: |
| type_str = "std"; |
| break; |
| case CIPSO_V4_MAP_PASS: |
| type_str = "pass"; |
| break; |
| default: |
| type_str = "(unknown)"; |
| } |
| audit_log_format(audit_buf, |
| " cipso_doi=%u cipso_type=%s res=%u", |
| doi_def->doi, |
| type_str, |
| ret_val == 0 ? 1 : 0); |
| audit_log_end(audit_buf); |
| } |
| |
| return ret_val; |
| } |
| |
| /** |
| * netlbl_cfg_cipsov4_add_map - Add a new CIPSOv4 DOI definition and mapping |
| * @doi_def: the DOI definition |
| * @domain: the domain mapping to add |
| * @audit_info: NetLabel audit information |
| * |
| * Description: |
| * Add a new CIPSOv4 DOI definition and NetLabel/LSM domain mapping for this |
| * new DOI definition to the NetLabel subsystem. A @domain value of NULL adds |
| * a new default domain mapping. Returns zero on success, negative values on |
| * failure. |
| * |
| */ |
| int netlbl_cfg_cipsov4_add_map(struct cipso_v4_doi *doi_def, |
| const char *domain, |
| struct netlbl_audit *audit_info) |
| { |
| int ret_val = -ENOMEM; |
| struct netlbl_dom_map *entry; |
| |
| entry = kzalloc(sizeof(*entry), GFP_ATOMIC); |
| if (entry == NULL) |
| goto cfg_cipsov4_add_map_failure; |
| if (domain != NULL) { |
| entry->domain = kstrdup(domain, GFP_ATOMIC); |
| if (entry->domain == NULL) |
| goto cfg_cipsov4_add_map_failure; |
| } |
| entry->type = NETLBL_NLTYPE_CIPSOV4; |
| entry->type_def.cipsov4 = doi_def; |
| |
| /* Grab a RCU read lock here so nothing happens to the doi_def variable |
| * between adding it to the CIPSOv4 protocol engine and adding a |
| * domain mapping for it. */ |
| |
| rcu_read_lock(); |
| ret_val = netlbl_cfg_cipsov4_add(doi_def, audit_info); |
| if (ret_val != 0) |
| goto cfg_cipsov4_add_map_failure_unlock; |
| ret_val = netlbl_domhsh_add(entry, audit_info); |
| if (ret_val != 0) |
| goto cfg_cipsov4_add_map_failure_remove_doi; |
| rcu_read_unlock(); |
| |
| return 0; |
| |
| cfg_cipsov4_add_map_failure_remove_doi: |
| cipso_v4_doi_remove(doi_def->doi, audit_info, netlbl_cipsov4_doi_free); |
| cfg_cipsov4_add_map_failure_unlock: |
| rcu_read_unlock(); |
| cfg_cipsov4_add_map_failure: |
| if (entry != NULL) |
| kfree(entry->domain); |
| kfree(entry); |
| return ret_val; |
| } |
| |
| /** |
| * netlbl_cfg_cipsov4_del - Removean existing CIPSOv4 DOI definition |
| * @doi: the CIPSO DOI value |
| * @audit_info: NetLabel audit information |
| * |
| * Description: |
| * Removes an existing CIPSOv4 DOI definition from the NetLabel subsystem. |
| * Returns zero on success, negative values on failure. |
| * |
| */ |
| int netlbl_cfg_cipsov4_del(u32 doi, struct netlbl_audit *audit_info) |
| { |
| return cipso_v4_doi_remove(doi, audit_info, netlbl_cipsov4_doi_free); |
| } |
| |
| /* |
| * 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_enabled - Determine if the NetLabel subsystem is enabled |
| * |
| * Description: |
| * The LSM can use this function to determine if it should use NetLabel |
| * security attributes in it's enforcement mechanism. Currently, NetLabel is |
| * considered to be enabled when it's configuration contains a valid setup for |
| * at least one labeled protocol (i.e. NetLabel can understand incoming |
| * labeled packets of at least one type); otherwise NetLabel is considered to |
| * be disabled. |
| * |
| */ |
| int netlbl_enabled(void) |
| { |
| /* At some point we probably want to expose this mechanism to the user |
| * as well so that admins can toggle NetLabel regardless of the |
| * configuration */ |
| return (atomic_read(&netlabel_mgmt_protocount) > 0); |
| } |
| |
| /** |
| * netlbl_socket_setattr - Label a socket using the correct protocol |
| * @sk: 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 @sk, |
| * which means it either needs to be in the process of being created or locked. |
| * Returns zero on success, negative values on failure. |
| * |
| */ |
| int netlbl_sock_setattr(struct sock *sk, |
| const struct netlbl_lsm_secattr *secattr) |
| { |
| int ret_val = -ENOENT; |
| struct netlbl_dom_map *dom_entry; |
| |
| 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_sock_setattr(sk, |
| 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 if 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) |
| { |
| return cipso_v4_sock_getattr(sk, secattr); |
| } |
| |
| /** |
| * netlbl_skbuff_getattr - Determine the security attributes of a packet |
| * @skb: the packet |
| * @family: protocol family |
| * @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, |
| u16 family, |
| struct netlbl_lsm_secattr *secattr) |
| { |
| if (CIPSO_V4_OPTEXIST(skb) && |
| cipso_v4_skbuff_getattr(skb, secattr) == 0) |
| return 0; |
| |
| return netlbl_unlabel_getattr(skb, family, 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_unlabel_init(NETLBL_UNLHSH_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); |