/* * 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.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/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 <net/sock.h> #include <net/netlink.h> #include <net/genetlink.h> #include <net/netlabel.h> #include <asm/bug.h> #include "netlabel_user.h" #include "netlabel_domainhash.h" #include "netlabel_unlabeled.h" /* Accept unlabeled packets flag */ static DEFINE_SPINLOCK(netlabel_unlabel_acceptflg_lock); static u8 netlabel_unlabel_acceptflg = 0; /* NetLabel Generic NETLINK CIPSOv4 family */ static struct genl_family netlbl_unlabel_gnl_family = { .id = GENL_ID_GENERATE, .hdrsize = 0, .name = NETLBL_NLTYPE_UNLABELED_NAME, .version = NETLBL_PROTO_VERSION, .maxattr = NLBL_UNLABEL_A_MAX, }; /* NetLabel Netlink attribute policy */ static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = { [NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 }, }; /* * Helper Functions */ /** * 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; rcu_read_lock(); old_val = netlabel_unlabel_acceptflg; spin_lock(&netlabel_unlabel_acceptflg_lock); netlabel_unlabel_acceptflg = value; spin_unlock(&netlabel_unlabel_acceptflg_lock); rcu_read_unlock(); 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); } } /* * 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; } rcu_read_lock(); ret_val = nla_put_u8(ans_skb, NLBL_UNLABEL_A_ACPTFLG, netlabel_unlabel_acceptflg); rcu_read_unlock(); if (ret_val != 0) goto list_failure; genlmsg_end(ans_skb, data); ret_val = genlmsg_reply(ans_skb, info); if (ret_val != 0) goto list_failure; return 0; list_failure: kfree_skb(ans_skb); return ret_val; } /* * NetLabel Generic NETLINK Command Definitions */ static struct genl_ops netlbl_unlabel_genl_c_accept = { .cmd = NLBL_UNLABEL_C_ACCEPT, .flags = GENL_ADMIN_PERM, .policy = netlbl_unlabel_genl_policy, .doit = netlbl_unlabel_accept, .dumpit = NULL, }; static struct genl_ops netlbl_unlabel_genl_c_list = { .cmd = NLBL_UNLABEL_C_LIST, .flags = 0, .policy = netlbl_unlabel_genl_policy, .doit = netlbl_unlabel_list, .dumpit = NULL, }; /* * 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 netlbl_unlabel_genl_init(void) { int ret_val; ret_val = genl_register_family(&netlbl_unlabel_gnl_family); if (ret_val != 0) return ret_val; ret_val = genl_register_ops(&netlbl_unlabel_gnl_family, &netlbl_unlabel_genl_c_accept); if (ret_val != 0) return ret_val; ret_val = genl_register_ops(&netlbl_unlabel_gnl_family, &netlbl_unlabel_genl_c_list); if (ret_val != 0) return ret_val; return 0; } /* * NetLabel KAPI Hooks */ /** * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet * @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(struct netlbl_lsm_secattr *secattr) { int ret_val; rcu_read_lock(); if (netlabel_unlabel_acceptflg == 1) { netlbl_secattr_init(secattr); ret_val = 0; } else ret_val = -ENOMSG; rcu_read_unlock(); return ret_val; } /** * 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 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 = 0; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (entry == NULL) return -ENOMEM; entry->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; }