netlabel_mgmt.c
/*
* NetLabel Management Support
*
* This file defines the management functions 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/socket.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/netlink.h>
#include <net/genetlink.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.h>
#include "netlabel_domainhash.h"
#include "netlabel_user.h"
#include "netlabel_mgmt.h"
/* NetLabel configured protocol count */
static DEFINE_SPINLOCK(netlabel_mgmt_protocount_lock);
static u32 netlabel_mgmt_protocount = 0;
/* Argument struct for netlbl_domhsh_walk() */
struct netlbl_domhsh_walk_arg {
struct netlink_callback *nl_cb;
struct sk_buff *skb;
u32 seq;
};
/* NetLabel Generic NETLINK CIPSOv4 family */
static struct genl_family netlbl_mgmt_gnl_family = {
.id = GENL_ID_GENERATE,
.hdrsize = 0,
.name = NETLBL_NLTYPE_MGMT_NAME,
.version = NETLBL_PROTO_VERSION,
.maxattr = NLBL_MGMT_A_MAX,
};
/* NetLabel Netlink attribute policy */
static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
[NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
[NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
[NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
[NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
};
/*
* NetLabel Misc Managment Functions
*/
/**
* netlbl_mgmt_protocount_inc - Increment the configured labeled protocol count
*
* Description:
* Increment the number of labeled protocol configurations in the current
* NetLabel configuration. Keep track of this for use in determining if
* NetLabel label enforcement should be active/enabled or not in the LSM.
*
*/
void netlbl_mgmt_protocount_inc(void)
{
rcu_read_lock();
spin_lock(&netlabel_mgmt_protocount_lock);
netlabel_mgmt_protocount++;
spin_unlock(&netlabel_mgmt_protocount_lock);
rcu_read_unlock();
}
/**
* netlbl_mgmt_protocount_dec - Decrement the configured labeled protocol count
*
* Description:
* Decrement the number of labeled protocol configurations in the current
* NetLabel configuration. Keep track of this for use in determining if
* NetLabel label enforcement should be active/enabled or not in the LSM.
*
*/
void netlbl_mgmt_protocount_dec(void)
{
rcu_read_lock();
spin_lock(&netlabel_mgmt_protocount_lock);
if (netlabel_mgmt_protocount > 0)
netlabel_mgmt_protocount--;
spin_unlock(&netlabel_mgmt_protocount_lock);
rcu_read_unlock();
}
/**
* netlbl_mgmt_protocount_value - Return the number of configured protocols
*
* Description:
* Return the number of labeled protocols in the current NetLabel
* configuration. This value is useful in determining if NetLabel label
* enforcement should be active/enabled or not in the LSM.
*
*/
u32 netlbl_mgmt_protocount_value(void)
{
u32 val;
rcu_read_lock();
val = netlabel_mgmt_protocount;
rcu_read_unlock();
return val;
}
/*
* NetLabel Command Handlers
*/
/**
* netlbl_mgmt_add - Handle an ADD message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated ADD message and add the domains from the message
* to the hash table. See netlabel.h for a description of the message format.
* Returns zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
{
int ret_val = -EINVAL;
struct netlbl_dom_map *entry = NULL;
size_t tmp_size;
u32 tmp_val;
struct netlbl_audit audit_info;
if (!info->attrs[NLBL_MGMT_A_DOMAIN] ||
!info->attrs[NLBL_MGMT_A_PROTOCOL])
goto add_failure;
netlbl_netlink_auditinfo(skb, &audit_info);
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
if (entry == NULL) {
ret_val = -ENOMEM;
goto add_failure;
}
tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
entry->domain = kmalloc(tmp_size, GFP_KERNEL);
if (entry->domain == NULL) {
ret_val = -ENOMEM;
goto add_failure;
}
entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
nla_strlcpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
switch (entry->type) {
case NETLBL_NLTYPE_UNLABELED:
ret_val = netlbl_domhsh_add(entry, &audit_info);
break;
case NETLBL_NLTYPE_CIPSOV4:
if (!info->attrs[NLBL_MGMT_A_CV4DOI])
goto add_failure;
tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
/* We should be holding a rcu_read_lock() here while we hold
* the result but since the entry will always be deleted when
* the CIPSO DOI is deleted we aren't going to keep the
* lock. */
rcu_read_lock();
entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
if (entry->type_def.cipsov4 == NULL) {
rcu_read_unlock();
goto add_failure;
}
ret_val = netlbl_domhsh_add(entry, &audit_info);
rcu_read_unlock();
break;
default:
goto add_failure;
}
if (ret_val != 0)
goto add_failure;
return 0;
add_failure:
if (entry)
kfree(entry->domain);
kfree(entry);
return ret_val;
}
/**
* netlbl_mgmt_remove - Handle a REMOVE message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated REMOVE message and remove the specified domain
* mappings. Returns zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
{
char *domain;
struct netlbl_audit audit_info;
if (!info->attrs[NLBL_MGMT_A_DOMAIN])
return -EINVAL;
netlbl_netlink_auditinfo(skb, &audit_info);
domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
return netlbl_domhsh_remove(domain, &audit_info);
}
/**
* netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
* @entry: the domain mapping hash table entry
* @arg: the netlbl_domhsh_walk_arg structure
*
* Description:
* This function is designed to be used as a callback to the
* netlbl_domhsh_walk() function for use in generating a response for a LISTALL
* message. Returns the size of the message on success, negative values on
* failure.
*
*/
static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
{
int ret_val = -ENOMEM;
struct netlbl_domhsh_walk_arg *cb_arg = arg;
void *data;
data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
cb_arg->seq, &netlbl_mgmt_gnl_family,
NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
if (data == NULL)
goto listall_cb_failure;
ret_val = nla_put_string(cb_arg->skb,
NLBL_MGMT_A_DOMAIN,
entry->domain);
if (ret_val != 0)
goto listall_cb_failure;
ret_val = nla_put_u32(cb_arg->skb, NLBL_MGMT_A_PROTOCOL, entry->type);
if (ret_val != 0)
goto listall_cb_failure;
switch (entry->type) {
case NETLBL_NLTYPE_CIPSOV4:
ret_val = nla_put_u32(cb_arg->skb,
NLBL_MGMT_A_CV4DOI,
entry->type_def.cipsov4->doi);
if (ret_val != 0)
goto listall_cb_failure;
break;
}
cb_arg->seq++;
return genlmsg_end(cb_arg->skb, data);
listall_cb_failure:
genlmsg_cancel(cb_arg->skb, data);
return ret_val;
}
/**
* netlbl_mgmt_listall - Handle a LISTALL message
* @skb: the NETLINK buffer
* @cb: the NETLINK callback
*
* Description:
* Process a user generated LISTALL message and dumps the domain hash table in
* a form suitable for use in a kernel generated LISTALL message. Returns zero
* on success, negative values on failure.
*
*/
static int netlbl_mgmt_listall(struct sk_buff *skb,
struct netlink_callback *cb)
{
struct netlbl_domhsh_walk_arg cb_arg;
u32 skip_bkt = cb->args[0];
u32 skip_chain = cb->args[1];
cb_arg.nl_cb = cb;
cb_arg.skb = skb;
cb_arg.seq = cb->nlh->nlmsg_seq;
netlbl_domhsh_walk(&skip_bkt,
&skip_chain,
netlbl_mgmt_listall_cb,
&cb_arg);
cb->args[0] = skip_bkt;
cb->args[1] = skip_chain;
return skb->len;
}
/**
* netlbl_mgmt_adddef - Handle an ADDDEF message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated ADDDEF message and respond accordingly. Returns
* zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
{
int ret_val = -EINVAL;
struct netlbl_dom_map *entry = NULL;
u32 tmp_val;
struct netlbl_audit audit_info;
if (!info->attrs[NLBL_MGMT_A_PROTOCOL])
goto adddef_failure;
netlbl_netlink_auditinfo(skb, &audit_info);
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
if (entry == NULL) {
ret_val = -ENOMEM;
goto adddef_failure;
}
entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
switch (entry->type) {
case NETLBL_NLTYPE_UNLABELED:
ret_val = netlbl_domhsh_add_default(entry, &audit_info);
break;
case NETLBL_NLTYPE_CIPSOV4:
if (!info->attrs[NLBL_MGMT_A_CV4DOI])
goto adddef_failure;
tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
/* We should be holding a rcu_read_lock() here while we hold
* the result but since the entry will always be deleted when
* the CIPSO DOI is deleted we aren't going to keep the
* lock. */
rcu_read_lock();
entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
if (entry->type_def.cipsov4 == NULL) {
rcu_read_unlock();
goto adddef_failure;
}
ret_val = netlbl_domhsh_add_default(entry, &audit_info);
rcu_read_unlock();
break;
default:
goto adddef_failure;
}
if (ret_val != 0)
goto adddef_failure;
return 0;
adddef_failure:
kfree(entry);
return ret_val;
}
/**
* netlbl_mgmt_removedef - Handle a REMOVEDEF message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated REMOVEDEF message and remove the default domain
* mapping. Returns zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
{
struct netlbl_audit audit_info;
netlbl_netlink_auditinfo(skb, &audit_info);
return netlbl_domhsh_remove_default(&audit_info);
}
/**
* netlbl_mgmt_listdef - Handle a LISTDEF message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated LISTDEF message and dumps the default domain
* mapping in a form suitable for use in a kernel generated LISTDEF message.
* Returns zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
{
int ret_val = -ENOMEM;
struct sk_buff *ans_skb = NULL;
void *data;
struct netlbl_dom_map *entry;
ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (ans_skb == NULL)
return -ENOMEM;
data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
0, NLBL_MGMT_C_LISTDEF);
if (data == NULL)
goto listdef_failure;
rcu_read_lock();
entry = netlbl_domhsh_getentry(NULL);
if (entry == NULL) {
ret_val = -ENOENT;
goto listdef_failure_lock;
}
ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_PROTOCOL, entry->type);
if (ret_val != 0)
goto listdef_failure_lock;
switch (entry->type) {
case NETLBL_NLTYPE_CIPSOV4:
ret_val = nla_put_u32(ans_skb,
NLBL_MGMT_A_CV4DOI,
entry->type_def.cipsov4->doi);
if (ret_val != 0)
goto listdef_failure_lock;
break;
}
rcu_read_unlock();
genlmsg_end(ans_skb, data);
ret_val = genlmsg_reply(ans_skb, info);
if (ret_val != 0)
goto listdef_failure;
return 0;
listdef_failure_lock:
rcu_read_unlock();
listdef_failure:
kfree_skb(ans_skb);
return ret_val;
}
/**
* netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
* @skb: the skb to write to
* @seq: the NETLINK sequence number
* @cb: the NETLINK callback
* @protocol: the NetLabel protocol to use in the message
*
* Description:
* This function is to be used in conjunction with netlbl_mgmt_protocols() to
* answer a application's PROTOCOLS message. Returns the size of the message
* on success, negative values on failure.
*
*/
static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
struct netlink_callback *cb,
u32 protocol)
{
int ret_val = -ENOMEM;
void *data;
data = genlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
&netlbl_mgmt_gnl_family, NLM_F_MULTI,
NLBL_MGMT_C_PROTOCOLS);
if (data == NULL)
goto protocols_cb_failure;
ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
if (ret_val != 0)
goto protocols_cb_failure;
return genlmsg_end(skb, data);
protocols_cb_failure:
genlmsg_cancel(skb, data);
return ret_val;
}
/**
* netlbl_mgmt_protocols - Handle a PROTOCOLS message
* @skb: the NETLINK buffer
* @cb: the NETLINK callback
*
* Description:
* Process a user generated PROTOCOLS message and respond accordingly.
*
*/
static int netlbl_mgmt_protocols(struct sk_buff *skb,
struct netlink_callback *cb)
{
u32 protos_sent = cb->args[0];
if (protos_sent == 0) {
if (netlbl_mgmt_protocols_cb(skb,
cb,
NETLBL_NLTYPE_UNLABELED) < 0)
goto protocols_return;
protos_sent++;
}
if (protos_sent == 1) {
if (netlbl_mgmt_protocols_cb(skb,
cb,
NETLBL_NLTYPE_CIPSOV4) < 0)
goto protocols_return;
protos_sent++;
}
protocols_return:
cb->args[0] = protos_sent;
return skb->len;
}
/**
* netlbl_mgmt_version - Handle a VERSION message
* @skb: the NETLINK buffer
* @info: the Generic NETLINK info block
*
* Description:
* Process a user generated VERSION message and respond accordingly. Returns
* zero on success, negative values on failure.
*
*/
static int netlbl_mgmt_version(struct sk_buff *skb, struct genl_info *info)
{
int ret_val = -ENOMEM;
struct sk_buff *ans_skb = NULL;
void *data;
ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
if (ans_skb == NULL)
return -ENOMEM;
data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
0, NLBL_MGMT_C_VERSION);
if (data == NULL)
goto version_failure;
ret_val = nla_put_u32(ans_skb,
NLBL_MGMT_A_VERSION,
NETLBL_PROTO_VERSION);
if (ret_val != 0)
goto version_failure;
genlmsg_end(ans_skb, data);
ret_val = genlmsg_reply(ans_skb, info);
if (ret_val != 0)
goto version_failure;
return 0;
version_failure:
kfree_skb(ans_skb);
return ret_val;
}
/*
* NetLabel Generic NETLINK Command Definitions
*/
static struct genl_ops netlbl_mgmt_genl_c_add = {
.cmd = NLBL_MGMT_C_ADD,
.flags = GENL_ADMIN_PERM,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_add,
.dumpit = NULL,
};
static struct genl_ops netlbl_mgmt_genl_c_remove = {
.cmd = NLBL_MGMT_C_REMOVE,
.flags = GENL_ADMIN_PERM,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_remove,
.dumpit = NULL,
};
static struct genl_ops netlbl_mgmt_genl_c_listall = {
.cmd = NLBL_MGMT_C_LISTALL,
.flags = 0,
.policy = netlbl_mgmt_genl_policy,
.doit = NULL,
.dumpit = netlbl_mgmt_listall,
};
static struct genl_ops netlbl_mgmt_genl_c_adddef = {
.cmd = NLBL_MGMT_C_ADDDEF,
.flags = GENL_ADMIN_PERM,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_adddef,
.dumpit = NULL,
};
static struct genl_ops netlbl_mgmt_genl_c_removedef = {
.cmd = NLBL_MGMT_C_REMOVEDEF,
.flags = GENL_ADMIN_PERM,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_removedef,
.dumpit = NULL,
};
static struct genl_ops netlbl_mgmt_genl_c_listdef = {
.cmd = NLBL_MGMT_C_LISTDEF,
.flags = 0,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_listdef,
.dumpit = NULL,
};
static struct genl_ops netlbl_mgmt_genl_c_protocols = {
.cmd = NLBL_MGMT_C_PROTOCOLS,
.flags = 0,
.policy = netlbl_mgmt_genl_policy,
.doit = NULL,
.dumpit = netlbl_mgmt_protocols,
};
static struct genl_ops netlbl_mgmt_genl_c_version = {
.cmd = NLBL_MGMT_C_VERSION,
.flags = 0,
.policy = netlbl_mgmt_genl_policy,
.doit = netlbl_mgmt_version,
.dumpit = NULL,
};
/*
* NetLabel Generic NETLINK Protocol Functions
*/
/**
* netlbl_mgmt_genl_init - Register the NetLabel management component
*
* Description:
* Register the NetLabel management component with the Generic NETLINK
* mechanism. Returns zero on success, negative values on failure.
*
*/
int netlbl_mgmt_genl_init(void)
{
int ret_val;
ret_val = genl_register_family(&netlbl_mgmt_gnl_family);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_add);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_remove);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_listall);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_adddef);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_removedef);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_listdef);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_protocols);
if (ret_val != 0)
return ret_val;
ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
&netlbl_mgmt_genl_c_version);
if (ret_val != 0)
return ret_val;
return 0;
}