allow coexistance of N build and AC build.

[tomato.git] / release / src-rt-6.x / linux / linux-2.6 / net / netlabel / 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"

/* 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 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;
}