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[/] [or1k_soc_on_altera_embedded_dev_kit/] [trunk/] [linux-2.6/] [linux-2.6.24/] [net/] [netlink/] [genetlink.c] - Blame information for rev 17

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/*
 * NETLINK      Generic Netlink Family
 *
 *              Authors:        Jamal Hadi Salim
 *                              Thomas Graf <tgraf@suug.ch>
 *                              Johannes Berg <johannes@sipsolutions.net>
 */
 
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/mutex.h>
#include <linux/bitmap.h>
#include <net/sock.h>
#include <net/genetlink.h>
 
struct sock *genl_sock = NULL;
 
static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
 
static inline void genl_lock(void)
{
        mutex_lock(&genl_mutex);
}
 
static inline void genl_unlock(void)
{
        mutex_unlock(&genl_mutex);
}
 
#define GENL_FAM_TAB_SIZE       16
#define GENL_FAM_TAB_MASK       (GENL_FAM_TAB_SIZE - 1)
 
static struct list_head family_ht[GENL_FAM_TAB_SIZE];
/*
 * Bitmap of multicast groups that are currently in use.
 *
 * To avoid an allocation at boot of just one unsigned long,
 * declare it global instead.
 * Bit 0 is marked as already used since group 0 is invalid.
 */
static unsigned long mc_group_start = 0x1;
static unsigned long *mc_groups = &mc_group_start;
static unsigned long mc_groups_longs = 1;
 
static int genl_ctrl_event(int event, void *data);
 
static inline unsigned int genl_family_hash(unsigned int id)
{
        return id & GENL_FAM_TAB_MASK;
}
 
static inline struct list_head *genl_family_chain(unsigned int id)
{
        return &family_ht[genl_family_hash(id)];
}
 
static struct genl_family *genl_family_find_byid(unsigned int id)
{
        struct genl_family *f;
 
        list_for_each_entry(f, genl_family_chain(id), family_list)
                if (f->id == id)
                        return f;
 
        return NULL;
}
 
static struct genl_family *genl_family_find_byname(char *name)
{
        struct genl_family *f;
        int i;
 
        for (i = 0; i < GENL_FAM_TAB_SIZE; i++)
                list_for_each_entry(f, genl_family_chain(i), family_list)
                        if (strcmp(f->name, name) == 0)
                                return f;
 
        return NULL;
}
 
static struct genl_ops *genl_get_cmd(u8 cmd, struct genl_family *family)
{
        struct genl_ops *ops;
 
        list_for_each_entry(ops, &family->ops_list, ops_list)
                if (ops->cmd == cmd)
                        return ops;
 
        return NULL;
}
 
/* Of course we are going to have problems once we hit
 * 2^16 alive types, but that can only happen by year 2K
*/
static inline u16 genl_generate_id(void)
{
        static u16 id_gen_idx;
        int overflowed = 0;
 
        do {
                if (id_gen_idx == 0)
                        id_gen_idx = GENL_MIN_ID;
 
                if (++id_gen_idx > GENL_MAX_ID) {
                        if (!overflowed) {
                                overflowed = 1;
                                id_gen_idx = 0;
                                continue;
                        } else
                                return 0;
                }
 
        } while (genl_family_find_byid(id_gen_idx));
 
        return id_gen_idx;
}
 
static struct genl_multicast_group notify_grp;
 
/**
 * genl_register_mc_group - register a multicast group
 *
 * Registers the specified multicast group and notifies userspace
 * about the new group.
 *
 * Returns 0 on success or a negative error code.
 *
 * @family: The generic netlink family the group shall be registered for.
 * @grp: The group to register, must have a name.
 */
int genl_register_mc_group(struct genl_family *family,
                           struct genl_multicast_group *grp)
{
        int id;
        unsigned long *new_groups;
        int err;
 
        BUG_ON(grp->name[0] == '\0');
 
        genl_lock();
 
        /* special-case our own group */
        if (grp == &notify_grp)
                id = GENL_ID_CTRL;
        else
                id = find_first_zero_bit(mc_groups,
                                         mc_groups_longs * BITS_PER_LONG);
 
 
        if (id >= mc_groups_longs * BITS_PER_LONG) {
                size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long);
 
                if (mc_groups == &mc_group_start) {
                        new_groups = kzalloc(nlen, GFP_KERNEL);
                        if (!new_groups) {
                                err = -ENOMEM;
                                goto out;
                        }
                        mc_groups = new_groups;
                        *mc_groups = mc_group_start;
                } else {
                        new_groups = krealloc(mc_groups, nlen, GFP_KERNEL);
                        if (!new_groups) {
                                err = -ENOMEM;
                                goto out;
                        }
                        mc_groups = new_groups;
                        mc_groups[mc_groups_longs] = 0;
                }
                mc_groups_longs++;
        }
 
        err = netlink_change_ngroups(genl_sock,
                                     mc_groups_longs * BITS_PER_LONG);
        if (err)
                goto out;
 
        grp->id = id;
        set_bit(id, mc_groups);
        list_add_tail(&grp->list, &family->mcast_groups);
        grp->family = family;
 
        genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp);
 out:
        genl_unlock();
        return err;
}
EXPORT_SYMBOL(genl_register_mc_group);
 
static void __genl_unregister_mc_group(struct genl_family *family,
                                       struct genl_multicast_group *grp)
{
        BUG_ON(grp->family != family);
        netlink_clear_multicast_users(genl_sock, grp->id);
        clear_bit(grp->id, mc_groups);
        list_del(&grp->list);
        genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);
        grp->id = 0;
        grp->family = NULL;
}
 
/**
 * genl_unregister_mc_group - unregister a multicast group
 *
 * Unregisters the specified multicast group and notifies userspace
 * about it. All current listeners on the group are removed.
 *
 * Note: It is not necessary to unregister all multicast groups before
 *       unregistering the family, unregistering the family will cause
 *       all assigned multicast groups to be unregistered automatically.
 *
 * @family: Generic netlink family the group belongs to.
 * @grp: The group to unregister, must have been registered successfully
 *       previously.
 */
void genl_unregister_mc_group(struct genl_family *family,
                              struct genl_multicast_group *grp)
{
        genl_lock();
        __genl_unregister_mc_group(family, grp);
        genl_unlock();
}
 
static void genl_unregister_mc_groups(struct genl_family *family)
{
        struct genl_multicast_group *grp, *tmp;
 
        genl_lock();
        list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list)
                __genl_unregister_mc_group(family, grp);
        genl_unlock();
}
 
/**
 * genl_register_ops - register generic netlink operations
 * @family: generic netlink family
 * @ops: operations to be registered
 *
 * Registers the specified operations and assigns them to the specified
 * family. Either a doit or dumpit callback must be specified or the
 * operation will fail. Only one operation structure per command
 * identifier may be registered.
 *
 * See include/net/genetlink.h for more documenation on the operations
 * structure.
 *
 * Returns 0 on success or a negative error code.
 */
int genl_register_ops(struct genl_family *family, struct genl_ops *ops)
{
        int err = -EINVAL;
 
        if (ops->dumpit == NULL && ops->doit == NULL)
                goto errout;
 
        if (genl_get_cmd(ops->cmd, family)) {
                err = -EEXIST;
                goto errout;
        }
 
        if (ops->dumpit)
                ops->flags |= GENL_CMD_CAP_DUMP;
        if (ops->doit)
                ops->flags |= GENL_CMD_CAP_DO;
        if (ops->policy)
                ops->flags |= GENL_CMD_CAP_HASPOL;
 
        genl_lock();
        list_add_tail(&ops->ops_list, &family->ops_list);
        genl_unlock();
 
        genl_ctrl_event(CTRL_CMD_NEWOPS, ops);
        err = 0;
errout:
        return err;
}
 
/**
 * genl_unregister_ops - unregister generic netlink operations
 * @family: generic netlink family
 * @ops: operations to be unregistered
 *
 * Unregisters the specified operations and unassigns them from the
 * specified family. The operation blocks until the current message
 * processing has finished and doesn't start again until the
 * unregister process has finished.
 *
 * Note: It is not necessary to unregister all operations before
 *       unregistering the family, unregistering the family will cause
 *       all assigned operations to be unregistered automatically.
 *
 * Returns 0 on success or a negative error code.
 */
int genl_unregister_ops(struct genl_family *family, struct genl_ops *ops)
{
        struct genl_ops *rc;
 
        genl_lock();
        list_for_each_entry(rc, &family->ops_list, ops_list) {
                if (rc == ops) {
                        list_del(&ops->ops_list);
                        genl_unlock();
                        genl_ctrl_event(CTRL_CMD_DELOPS, ops);
                        return 0;
                }
        }
        genl_unlock();
 
        return -ENOENT;
}
 
/**
 * genl_register_family - register a generic netlink family
 * @family: generic netlink family
 *
 * Registers the specified family after validating it first. Only one
 * family may be registered with the same family name or identifier.
 * The family id may equal GENL_ID_GENERATE causing an unique id to
 * be automatically generated and assigned.
 *
 * Return 0 on success or a negative error code.
 */
int genl_register_family(struct genl_family *family)
{
        int err = -EINVAL;
 
        if (family->id && family->id < GENL_MIN_ID)
                goto errout;
 
        if (family->id > GENL_MAX_ID)
                goto errout;
 
        INIT_LIST_HEAD(&family->ops_list);
        INIT_LIST_HEAD(&family->mcast_groups);
 
        genl_lock();
 
        if (genl_family_find_byname(family->name)) {
                err = -EEXIST;
                goto errout_locked;
        }
 
        if (genl_family_find_byid(family->id)) {
                err = -EEXIST;
                goto errout_locked;
        }
 
        if (family->id == GENL_ID_GENERATE) {
                u16 newid = genl_generate_id();
 
                if (!newid) {
                        err = -ENOMEM;
                        goto errout_locked;
                }
 
                family->id = newid;
        }
 
        if (family->maxattr) {
                family->attrbuf = kmalloc((family->maxattr+1) *
                                        sizeof(struct nlattr *), GFP_KERNEL);
                if (family->attrbuf == NULL) {
                        err = -ENOMEM;
                        goto errout_locked;
                }
        } else
                family->attrbuf = NULL;
 
        list_add_tail(&family->family_list, genl_family_chain(family->id));
        genl_unlock();
 
        genl_ctrl_event(CTRL_CMD_NEWFAMILY, family);
 
        return 0;
 
errout_locked:
        genl_unlock();
errout:
        return err;
}
 
/**
 * genl_unregister_family - unregister generic netlink family
 * @family: generic netlink family
 *
 * Unregisters the specified family.
 *
 * Returns 0 on success or a negative error code.
 */
int genl_unregister_family(struct genl_family *family)
{
        struct genl_family *rc;
 
        genl_unregister_mc_groups(family);
 
        genl_lock();
 
        list_for_each_entry(rc, genl_family_chain(family->id), family_list) {
                if (family->id != rc->id || strcmp(rc->name, family->name))
                        continue;
 
                list_del(&rc->family_list);
                INIT_LIST_HEAD(&family->ops_list);
                genl_unlock();
 
                kfree(family->attrbuf);
                genl_ctrl_event(CTRL_CMD_DELFAMILY, family);
                return 0;
        }
 
        genl_unlock();
 
        return -ENOENT;
}
 
static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
{
        struct genl_ops *ops;
        struct genl_family *family;
        struct genl_info info;
        struct genlmsghdr *hdr = nlmsg_data(nlh);
        int hdrlen, err;
 
        family = genl_family_find_byid(nlh->nlmsg_type);
        if (family == NULL)
                return -ENOENT;
 
        hdrlen = GENL_HDRLEN + family->hdrsize;
        if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
                return -EINVAL;
 
        ops = genl_get_cmd(hdr->cmd, family);
        if (ops == NULL)
                return -EOPNOTSUPP;
 
        if ((ops->flags & GENL_ADMIN_PERM) &&
            security_netlink_recv(skb, CAP_NET_ADMIN))
                return -EPERM;
 
        if (nlh->nlmsg_flags & NLM_F_DUMP) {
                if (ops->dumpit == NULL)
                        return -EOPNOTSUPP;
 
                return netlink_dump_start(genl_sock, skb, nlh,
                                          ops->dumpit, ops->done);
        }
 
        if (ops->doit == NULL)
                return -EOPNOTSUPP;
 
        if (family->attrbuf) {
                err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr,
                                  ops->policy);
                if (err < 0)
                        return err;
        }
 
        info.snd_seq = nlh->nlmsg_seq;
        info.snd_pid = NETLINK_CB(skb).pid;
        info.nlhdr = nlh;
        info.genlhdr = nlmsg_data(nlh);
        info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
        info.attrs = family->attrbuf;
 
        return ops->doit(skb, &info);
}
 
static void genl_rcv(struct sk_buff *skb)
{
        genl_lock();
        netlink_rcv_skb(skb, &genl_rcv_msg);
        genl_unlock();
}
 
/**************************************************************************
 * Controller
 **************************************************************************/
 
static struct genl_family genl_ctrl = {
        .id = GENL_ID_CTRL,
        .name = "nlctrl",
        .version = 0x2,
        .maxattr = CTRL_ATTR_MAX,
};
 
static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,
                          u32 flags, struct sk_buff *skb, u8 cmd)
{
        void *hdr;
 
        hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);
        if (hdr == NULL)
                return -1;
 
        NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name);
        NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id);
        NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version);
        NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize);
        NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr);
 
        if (!list_empty(&family->ops_list)) {
                struct nlattr *nla_ops;
                struct genl_ops *ops;
                int idx = 1;
 
                nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS);
                if (nla_ops == NULL)
                        goto nla_put_failure;
 
                list_for_each_entry(ops, &family->ops_list, ops_list) {
                        struct nlattr *nest;
 
                        nest = nla_nest_start(skb, idx++);
                        if (nest == NULL)
                                goto nla_put_failure;
 
                        NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd);
                        NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags);
 
                        nla_nest_end(skb, nest);
                }
 
                nla_nest_end(skb, nla_ops);
        }
 
        if (!list_empty(&family->mcast_groups)) {
                struct genl_multicast_group *grp;
                struct nlattr *nla_grps;
                int idx = 1;
 
                nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);
                if (nla_grps == NULL)
                        goto nla_put_failure;
 
                list_for_each_entry(grp, &family->mcast_groups, list) {
                        struct nlattr *nest;
 
                        nest = nla_nest_start(skb, idx++);
                        if (nest == NULL)
                                goto nla_put_failure;
 
                        NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);
                        NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,
                                       grp->name);
 
                        nla_nest_end(skb, nest);
                }
                nla_nest_end(skb, nla_grps);
        }
 
        return genlmsg_end(skb, hdr);
 
nla_put_failure:
        return genlmsg_cancel(skb, hdr);
}
 
static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid,
                                u32 seq, u32 flags, struct sk_buff *skb,
                                u8 cmd)
{
        void *hdr;
        struct nlattr *nla_grps;
        struct nlattr *nest;
 
        hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);
        if (hdr == NULL)
                return -1;
 
        NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name);
        NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id);
 
        nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);
        if (nla_grps == NULL)
                goto nla_put_failure;
 
        nest = nla_nest_start(skb, 1);
        if (nest == NULL)
                goto nla_put_failure;
 
        NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);
        NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,
                       grp->name);
 
        nla_nest_end(skb, nest);
        nla_nest_end(skb, nla_grps);
 
        return genlmsg_end(skb, hdr);
 
nla_put_failure:
        return genlmsg_cancel(skb, hdr);
}
 
static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
{
 
        int i, n = 0;
        struct genl_family *rt;
        int chains_to_skip = cb->args[0];
        int fams_to_skip = cb->args[1];
 
        if (chains_to_skip != 0)
                genl_lock();
 
        for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {
                if (i < chains_to_skip)
                        continue;
                n = 0;
                list_for_each_entry(rt, genl_family_chain(i), family_list) {
                        if (++n < fams_to_skip)
                                continue;
                        if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid,
                                           cb->nlh->nlmsg_seq, NLM_F_MULTI,
                                           skb, CTRL_CMD_NEWFAMILY) < 0)
                                goto errout;
                }
 
                fams_to_skip = 0;
        }
 
errout:
        if (chains_to_skip != 0)
                genl_unlock();
 
        cb->args[0] = i;
        cb->args[1] = n;
 
        return skb->len;
}
 
static struct sk_buff *ctrl_build_family_msg(struct genl_family *family,
                                             u32 pid, int seq, u8 cmd)
{
        struct sk_buff *skb;
        int err;
 
        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
        if (skb == NULL)
                return ERR_PTR(-ENOBUFS);
 
        err = ctrl_fill_info(family, pid, seq, 0, skb, cmd);
        if (err < 0) {
                nlmsg_free(skb);
                return ERR_PTR(err);
        }
 
        return skb;
}
 
static struct sk_buff *ctrl_build_mcgrp_msg(struct genl_multicast_group *grp,
                                            u32 pid, int seq, u8 cmd)
{
        struct sk_buff *skb;
        int err;
 
        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
        if (skb == NULL)
                return ERR_PTR(-ENOBUFS);
 
        err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd);
        if (err < 0) {
                nlmsg_free(skb);
                return ERR_PTR(err);
        }
 
        return skb;
}
 
static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {
        [CTRL_ATTR_FAMILY_ID]   = { .type = NLA_U16 },
        [CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
                                    .len = GENL_NAMSIZ - 1 },
};
 
static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
{
        struct sk_buff *msg;
        struct genl_family *res = NULL;
        int err = -EINVAL;
 
        if (info->attrs[CTRL_ATTR_FAMILY_ID]) {
                u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);
                res = genl_family_find_byid(id);
        }
 
        if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {
                char *name;
 
                name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);
                res = genl_family_find_byname(name);
        }
 
        if (res == NULL) {
                err = -ENOENT;
                goto errout;
        }
 
        msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq,
                                    CTRL_CMD_NEWFAMILY);
        if (IS_ERR(msg)) {
                err = PTR_ERR(msg);
                goto errout;
        }
 
        err = genlmsg_reply(msg, info);
errout:
        return err;
}
 
static int genl_ctrl_event(int event, void *data)
{
        struct sk_buff *msg;
 
        if (genl_sock == NULL)
                return 0;
 
        switch (event) {
        case CTRL_CMD_NEWFAMILY:
        case CTRL_CMD_DELFAMILY:
                msg = ctrl_build_family_msg(data, 0, 0, event);
                if (IS_ERR(msg))
                        return PTR_ERR(msg);
 
                genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);
                break;
        case CTRL_CMD_NEWMCAST_GRP:
        case CTRL_CMD_DELMCAST_GRP:
                msg = ctrl_build_mcgrp_msg(data, 0, 0, event);
                if (IS_ERR(msg))
                        return PTR_ERR(msg);
 
                genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);
                break;
        }
 
        return 0;
}
 
static struct genl_ops genl_ctrl_ops = {
        .cmd            = CTRL_CMD_GETFAMILY,
        .doit           = ctrl_getfamily,
        .dumpit         = ctrl_dumpfamily,
        .policy         = ctrl_policy,
};
 
static struct genl_multicast_group notify_grp = {
        .name           = "notify",
};
 
static int __init genl_init(void)
{
        int i, err;
 
        for (i = 0; i < GENL_FAM_TAB_SIZE; i++)
                INIT_LIST_HEAD(&family_ht[i]);
 
        err = genl_register_family(&genl_ctrl);
        if (err < 0)
                goto errout;
 
        err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops);
        if (err < 0)
                goto errout_register;
 
        netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV);
 
        /* we'll bump the group number right afterwards */
        genl_sock = netlink_kernel_create(&init_net, NETLINK_GENERIC, 0,
                                          genl_rcv, NULL, THIS_MODULE);
        if (genl_sock == NULL)
                panic("GENL: Cannot initialize generic netlink\n");
 
        err = genl_register_mc_group(&genl_ctrl, &notify_grp);
        if (err < 0)
                goto errout_register;
 
        return 0;
 
errout_register:
        genl_unregister_family(&genl_ctrl);
errout:
        panic("GENL: Cannot register controller: %d\n", err);
}
 
subsys_initcall(genl_init);
 
EXPORT_SYMBOL(genl_sock);
EXPORT_SYMBOL(genl_register_ops);
EXPORT_SYMBOL(genl_unregister_ops);
EXPORT_SYMBOL(genl_register_family);
EXPORT_SYMBOL(genl_unregister_family);

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Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

[/] [or1k_soc_on_altera_embedded_dev_kit/] [trunk/] [linux-2.6/] [linux-2.6.24/] [net/] [netlink/] [genetlink.c] - Blame information for rev 17

Line No.	Rev	Author	Line
1	3	xianfeng	`/*`
2			`* NETLINK Generic Netlink Family`
3			`*`
4			`* Authors: Jamal Hadi Salim`
5			`* Thomas Graf <tgraf@suug.ch>`
6			`* Johannes Berg <johannes@sipsolutions.net>`
7			`*/`
8
9			`#include <linux/module.h>`
10			`#include <linux/kernel.h>`
11			`#include <linux/errno.h>`
12			`#include <linux/types.h>`
13			`#include <linux/socket.h>`
14			`#include <linux/string.h>`
15			`#include <linux/skbuff.h>`
16			`#include <linux/mutex.h>`
17			`#include <linux/bitmap.h>`
18			`#include <net/sock.h>`
19			`#include <net/genetlink.h>`
20
21			`struct sock *genl_sock = NULL;`
22
23			`static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */`
24
25			`static inline void genl_lock(void)`
26			`{`
27			`mutex_lock(&genl_mutex);`
28			`}`
29
30			`static inline void genl_unlock(void)`
31			`{`
32			`mutex_unlock(&genl_mutex);`
33			`}`
34
35			`#define GENL_FAM_TAB_SIZE 16`
36			`#define GENL_FAM_TAB_MASK (GENL_FAM_TAB_SIZE - 1)`
37
38			`static struct list_head family_ht[GENL_FAM_TAB_SIZE];`
39			`/*`
40			`* Bitmap of multicast groups that are currently in use.`
41			`*`
42			`* To avoid an allocation at boot of just one unsigned long,`
43			`* declare it global instead.`
44			`* Bit 0 is marked as already used since group 0 is invalid.`
45			`*/`
46			`static unsigned long mc_group_start = 0x1;`
47			`static unsigned long *mc_groups = &mc_group_start;`
48			`static unsigned long mc_groups_longs = 1;`
49
50			`static int genl_ctrl_event(int event, void *data);`
51
52			`static inline unsigned int genl_family_hash(unsigned int id)`
53			`{`
54			`return id & GENL_FAM_TAB_MASK;`
55			`}`
56
57			`static inline struct list_head *genl_family_chain(unsigned int id)`
58			`{`
59			`return &family_ht[genl_family_hash(id)];`
60			`}`
61
62			`static struct genl_family *genl_family_find_byid(unsigned int id)`
63			`{`
64			`struct genl_family *f;`
65
66			`list_for_each_entry(f, genl_family_chain(id), family_list)`
67			`if (f->id == id)`
68			`return f;`
69
70			`return NULL;`
71			`}`
72
73			`static struct genl_family genl_family_find_byname(char name)`
74			`{`
75			`struct genl_family *f;`
76			`int i;`
77
78			`for (i = 0; i < GENL_FAM_TAB_SIZE; i++)`
79			`list_for_each_entry(f, genl_family_chain(i), family_list)`
80			`if (strcmp(f->name, name) == 0)`
81			`return f;`
82
83			`return NULL;`
84			`}`
85
86			`static struct genl_ops genl_get_cmd(u8 cmd, struct genl_family family)`
87			`{`
88			`struct genl_ops *ops;`
89
90			`list_for_each_entry(ops, &family->ops_list, ops_list)`
91			`if (ops->cmd == cmd)`
92			`return ops;`
93
94			`return NULL;`
95			`}`
96
97			`/* Of course we are going to have problems once we hit`
98			`* 2^16 alive types, but that can only happen by year 2K`
99			`*/`
100			`static inline u16 genl_generate_id(void)`
101			`{`
102			`static u16 id_gen_idx;`
103			`int overflowed = 0;`
104
105			`do {`
106			`if (id_gen_idx == 0)`
107			`id_gen_idx = GENL_MIN_ID;`
108
109			`if (++id_gen_idx > GENL_MAX_ID) {`
110			`if (!overflowed) {`
111			`overflowed = 1;`
112			`id_gen_idx = 0;`
113			`continue;`
114			`} else`
115			`return 0;`
116			`}`
117
118			`} while (genl_family_find_byid(id_gen_idx));`
119
120			`return id_gen_idx;`
121			`}`
122
123			`static struct genl_multicast_group notify_grp;`
124
125			`/**`
126			`* genl_register_mc_group - register a multicast group`
127			`*`
128			`* Registers the specified multicast group and notifies userspace`
129			`* about the new group.`
130			`*`
131			`* Returns 0 on success or a negative error code.`
132			`*`
133			`* @family: The generic netlink family the group shall be registered for.`
134			`* @grp: The group to register, must have a name.`
135			`*/`
136			`int genl_register_mc_group(struct genl_family *family,`
137			`struct genl_multicast_group *grp)`
138			`{`
139			`int id;`
140			`unsigned long *new_groups;`
141			`int err;`
142
143			`BUG_ON(grp->name[0] == '\0');`
144
145			`genl_lock();`
146
147			`/* special-case our own group */`
148			`if (grp == &notify_grp)`
149			`id = GENL_ID_CTRL;`
150			`else`
151			`id = find_first_zero_bit(mc_groups,`
152			`mc_groups_longs * BITS_PER_LONG);`
153
154
155			`if (id >= mc_groups_longs * BITS_PER_LONG) {`
156			`size_t nlen = (mc_groups_longs + 1) * sizeof(unsigned long);`
157
158			`if (mc_groups == &mc_group_start) {`
159			`new_groups = kzalloc(nlen, GFP_KERNEL);`
160			`if (!new_groups) {`
161			`err = -ENOMEM;`
162			`goto out;`
163			`}`
164			`mc_groups = new_groups;`
165			`*mc_groups = mc_group_start;`
166			`} else {`
167			`new_groups = krealloc(mc_groups, nlen, GFP_KERNEL);`
168			`if (!new_groups) {`
169			`err = -ENOMEM;`
170			`goto out;`
171			`}`
172			`mc_groups = new_groups;`
173			`mc_groups[mc_groups_longs] = 0;`
174			`}`
175			`mc_groups_longs++;`
176			`}`
177
178			`err = netlink_change_ngroups(genl_sock,`
179			`mc_groups_longs * BITS_PER_LONG);`
180			`if (err)`
181			`goto out;`
182
183			`grp->id = id;`
184			`set_bit(id, mc_groups);`
185			`list_add_tail(&grp->list, &family->mcast_groups);`
186			`grp->family = family;`
187
188			`genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, grp);`
189			`out:`
190			`genl_unlock();`
191			`return err;`
192			`}`
193			`EXPORT_SYMBOL(genl_register_mc_group);`
194
195			`static void __genl_unregister_mc_group(struct genl_family *family,`
196			`struct genl_multicast_group *grp)`
197			`{`
198			`BUG_ON(grp->family != family);`
199			`netlink_clear_multicast_users(genl_sock, grp->id);`
200			`clear_bit(grp->id, mc_groups);`
201			`list_del(&grp->list);`
202			`genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, grp);`
203			`grp->id = 0;`
204			`grp->family = NULL;`
205			`}`
206
207			`/**`
208			`* genl_unregister_mc_group - unregister a multicast group`
209			`*`
210			`* Unregisters the specified multicast group and notifies userspace`
211			`* about it. All current listeners on the group are removed.`
212			`*`
213			`* Note: It is not necessary to unregister all multicast groups before`
214			`* unregistering the family, unregistering the family will cause`
215			`* all assigned multicast groups to be unregistered automatically.`
216			`*`
217			`* @family: Generic netlink family the group belongs to.`
218			`* @grp: The group to unregister, must have been registered successfully`
219			`* previously.`
220			`*/`
221			`void genl_unregister_mc_group(struct genl_family *family,`
222			`struct genl_multicast_group *grp)`
223			`{`
224			`genl_lock();`
225			`__genl_unregister_mc_group(family, grp);`
226			`genl_unlock();`
227			`}`
228
229			`static void genl_unregister_mc_groups(struct genl_family *family)`
230			`{`
231			`struct genl_multicast_group grp, tmp;`
232
233			`genl_lock();`
234			`list_for_each_entry_safe(grp, tmp, &family->mcast_groups, list)`
235			`__genl_unregister_mc_group(family, grp);`
236			`genl_unlock();`
237			`}`
238
239			`/**`
240			`* genl_register_ops - register generic netlink operations`
241			`* @family: generic netlink family`
242			`* @ops: operations to be registered`
243			`*`
244			`* Registers the specified operations and assigns them to the specified`
245			`* family. Either a doit or dumpit callback must be specified or the`
246			`* operation will fail. Only one operation structure per command`
247			`* identifier may be registered.`
248			`*`
249			`* See include/net/genetlink.h for more documenation on the operations`
250			`* structure.`
251			`*`
252			`* Returns 0 on success or a negative error code.`
253			`*/`
254			`int genl_register_ops(struct genl_family family, struct genl_ops ops)`
255			`{`
256			`int err = -EINVAL;`
257
258			`if (ops->dumpit == NULL && ops->doit == NULL)`
259			`goto errout;`
260
261			`if (genl_get_cmd(ops->cmd, family)) {`
262			`err = -EEXIST;`
263			`goto errout;`
264			`}`
265
266			`if (ops->dumpit)`
267			`ops->flags \|= GENL_CMD_CAP_DUMP;`
268			`if (ops->doit)`
269			`ops->flags \|= GENL_CMD_CAP_DO;`
270			`if (ops->policy)`
271			`ops->flags \|= GENL_CMD_CAP_HASPOL;`
272
273			`genl_lock();`
274			`list_add_tail(&ops->ops_list, &family->ops_list);`
275			`genl_unlock();`
276
277			`genl_ctrl_event(CTRL_CMD_NEWOPS, ops);`
278			`err = 0;`
279			`errout:`
280			`return err;`
281			`}`
282
283			`/**`
284			`* genl_unregister_ops - unregister generic netlink operations`
285			`* @family: generic netlink family`
286			`* @ops: operations to be unregistered`
287			`*`
288			`* Unregisters the specified operations and unassigns them from the`
289			`* specified family. The operation blocks until the current message`
290			`* processing has finished and doesn't start again until the`
291			`* unregister process has finished.`
292			`*`
293			`* Note: It is not necessary to unregister all operations before`
294			`* unregistering the family, unregistering the family will cause`
295			`* all assigned operations to be unregistered automatically.`
296			`*`
297			`* Returns 0 on success or a negative error code.`
298			`*/`
299			`int genl_unregister_ops(struct genl_family family, struct genl_ops ops)`
300			`{`
301			`struct genl_ops *rc;`
302
303			`genl_lock();`
304			`list_for_each_entry(rc, &family->ops_list, ops_list) {`
305			`if (rc == ops) {`
306			`list_del(&ops->ops_list);`
307			`genl_unlock();`
308			`genl_ctrl_event(CTRL_CMD_DELOPS, ops);`
309			`return 0;`
310			`}`
311			`}`
312			`genl_unlock();`
313
314			`return -ENOENT;`
315			`}`
316
317			`/**`
318			`* genl_register_family - register a generic netlink family`
319			`* @family: generic netlink family`
320			`*`
321			`* Registers the specified family after validating it first. Only one`
322			`* family may be registered with the same family name or identifier.`
323			`* The family id may equal GENL_ID_GENERATE causing an unique id to`
324			`* be automatically generated and assigned.`
325			`*`
326			`* Return 0 on success or a negative error code.`
327			`*/`
328			`int genl_register_family(struct genl_family *family)`
329			`{`
330			`int err = -EINVAL;`
331
332			`if (family->id && family->id < GENL_MIN_ID)`
333			`goto errout;`
334
335			`if (family->id > GENL_MAX_ID)`
336			`goto errout;`
337
338			`INIT_LIST_HEAD(&family->ops_list);`
339			`INIT_LIST_HEAD(&family->mcast_groups);`
340
341			`genl_lock();`
342
343			`if (genl_family_find_byname(family->name)) {`
344			`err = -EEXIST;`
345			`goto errout_locked;`
346			`}`
347
348			`if (genl_family_find_byid(family->id)) {`
349			`err = -EEXIST;`
350			`goto errout_locked;`
351			`}`
352
353			`if (family->id == GENL_ID_GENERATE) {`
354			`u16 newid = genl_generate_id();`
355
356			`if (!newid) {`
357			`err = -ENOMEM;`
358			`goto errout_locked;`
359			`}`
360
361			`family->id = newid;`
362			`}`
363
364			`if (family->maxattr) {`
365			`family->attrbuf = kmalloc((family->maxattr+1) *`
366			`sizeof(struct nlattr *), GFP_KERNEL);`
367			`if (family->attrbuf == NULL) {`
368			`err = -ENOMEM;`
369			`goto errout_locked;`
370			`}`
371			`} else`
372			`family->attrbuf = NULL;`
373
374			`list_add_tail(&family->family_list, genl_family_chain(family->id));`
375			`genl_unlock();`
376
377			`genl_ctrl_event(CTRL_CMD_NEWFAMILY, family);`
378
379			`return 0;`
380
381			`errout_locked:`
382			`genl_unlock();`
383			`errout:`
384			`return err;`
385			`}`
386
387			`/**`
388			`* genl_unregister_family - unregister generic netlink family`
389			`* @family: generic netlink family`
390			`*`
391			`* Unregisters the specified family.`
392			`*`
393			`* Returns 0 on success or a negative error code.`
394			`*/`
395			`int genl_unregister_family(struct genl_family *family)`
396			`{`
397			`struct genl_family *rc;`
398
399			`genl_unregister_mc_groups(family);`
400
401			`genl_lock();`
402
403			`list_for_each_entry(rc, genl_family_chain(family->id), family_list) {`
404			`if (family->id != rc->id \|\| strcmp(rc->name, family->name))`
405			`continue;`
406
407			`list_del(&rc->family_list);`
408			`INIT_LIST_HEAD(&family->ops_list);`
409			`genl_unlock();`
410
411			`kfree(family->attrbuf);`
412			`genl_ctrl_event(CTRL_CMD_DELFAMILY, family);`
413			`return 0;`
414			`}`
415
416			`genl_unlock();`
417
418			`return -ENOENT;`
419			`}`
420
421			`static int genl_rcv_msg(struct sk_buff skb, struct nlmsghdr nlh)`
422			`{`
423			`struct genl_ops *ops;`
424			`struct genl_family *family;`
425			`struct genl_info info;`
426			`struct genlmsghdr *hdr = nlmsg_data(nlh);`
427			`int hdrlen, err;`
428
429			`family = genl_family_find_byid(nlh->nlmsg_type);`
430			`if (family == NULL)`
431			`return -ENOENT;`
432
433			`hdrlen = GENL_HDRLEN + family->hdrsize;`
434			`if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))`
435			`return -EINVAL;`
436
437			`ops = genl_get_cmd(hdr->cmd, family);`
438			`if (ops == NULL)`
439			`return -EOPNOTSUPP;`
440
441			`if ((ops->flags & GENL_ADMIN_PERM) &&`
442			`security_netlink_recv(skb, CAP_NET_ADMIN))`
443			`return -EPERM;`
444
445			`if (nlh->nlmsg_flags & NLM_F_DUMP) {`
446			`if (ops->dumpit == NULL)`
447			`return -EOPNOTSUPP;`
448
449			`return netlink_dump_start(genl_sock, skb, nlh,`
450			`ops->dumpit, ops->done);`
451			`}`
452
453			`if (ops->doit == NULL)`
454			`return -EOPNOTSUPP;`
455
456			`if (family->attrbuf) {`
457			`err = nlmsg_parse(nlh, hdrlen, family->attrbuf, family->maxattr,`
458			`ops->policy);`
459			`if (err < 0)`
460			`return err;`
461			`}`
462
463			`info.snd_seq = nlh->nlmsg_seq;`
464			`info.snd_pid = NETLINK_CB(skb).pid;`
465			`info.nlhdr = nlh;`
466			`info.genlhdr = nlmsg_data(nlh);`
467			`info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;`
468			`info.attrs = family->attrbuf;`
469
470			`return ops->doit(skb, &info);`
471			`}`
472
473			`static void genl_rcv(struct sk_buff *skb)`
474			`{`
475			`genl_lock();`
476			`netlink_rcv_skb(skb, &genl_rcv_msg);`
477			`genl_unlock();`
478			`}`
479
480			`/**************************************************************************`
481			`* Controller`
482			`**************************************************************************/`
483
484			`static struct genl_family genl_ctrl = {`
485			`.id = GENL_ID_CTRL,`
486			`.name = "nlctrl",`
487			`.version = 0x2,`
488			`.maxattr = CTRL_ATTR_MAX,`
489			`};`
490
491			`static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,`
492			`u32 flags, struct sk_buff *skb, u8 cmd)`
493			`{`
494			`void *hdr;`
495
496			`hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);`
497			`if (hdr == NULL)`
498			`return -1;`
499
500			`NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, family->name);`
501			`NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, family->id);`
502			`NLA_PUT_U32(skb, CTRL_ATTR_VERSION, family->version);`
503			`NLA_PUT_U32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize);`
504			`NLA_PUT_U32(skb, CTRL_ATTR_MAXATTR, family->maxattr);`
505
506			`if (!list_empty(&family->ops_list)) {`
507			`struct nlattr *nla_ops;`
508			`struct genl_ops *ops;`
509			`int idx = 1;`
510
511			`nla_ops = nla_nest_start(skb, CTRL_ATTR_OPS);`
512			`if (nla_ops == NULL)`
513			`goto nla_put_failure;`
514
515			`list_for_each_entry(ops, &family->ops_list, ops_list) {`
516			`struct nlattr *nest;`
517
518			`nest = nla_nest_start(skb, idx++);`
519			`if (nest == NULL)`
520			`goto nla_put_failure;`
521
522			`NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd);`
523			`NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags);`
524
525			`nla_nest_end(skb, nest);`
526			`}`
527
528			`nla_nest_end(skb, nla_ops);`
529			`}`
530
531			`if (!list_empty(&family->mcast_groups)) {`
532			`struct genl_multicast_group *grp;`
533			`struct nlattr *nla_grps;`
534			`int idx = 1;`
535
536			`nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);`
537			`if (nla_grps == NULL)`
538			`goto nla_put_failure;`
539
540			`list_for_each_entry(grp, &family->mcast_groups, list) {`
541			`struct nlattr *nest;`
542
543			`nest = nla_nest_start(skb, idx++);`
544			`if (nest == NULL)`
545			`goto nla_put_failure;`
546
547			`NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);`
548			`NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,`
549			`grp->name);`
550
551			`nla_nest_end(skb, nest);`
552			`}`
553			`nla_nest_end(skb, nla_grps);`
554			`}`
555
556			`return genlmsg_end(skb, hdr);`
557
558			`nla_put_failure:`
559			`return genlmsg_cancel(skb, hdr);`
560			`}`
561
562			`static int ctrl_fill_mcgrp_info(struct genl_multicast_group *grp, u32 pid,`
563			`u32 seq, u32 flags, struct sk_buff *skb,`
564			`u8 cmd)`
565			`{`
566			`void *hdr;`
567			`struct nlattr *nla_grps;`
568			`struct nlattr *nest;`
569
570			`hdr = genlmsg_put(skb, pid, seq, &genl_ctrl, flags, cmd);`
571			`if (hdr == NULL)`
572			`return -1;`
573
574			`NLA_PUT_STRING(skb, CTRL_ATTR_FAMILY_NAME, grp->family->name);`
575			`NLA_PUT_U16(skb, CTRL_ATTR_FAMILY_ID, grp->family->id);`
576
577			`nla_grps = nla_nest_start(skb, CTRL_ATTR_MCAST_GROUPS);`
578			`if (nla_grps == NULL)`
579			`goto nla_put_failure;`
580
581			`nest = nla_nest_start(skb, 1);`
582			`if (nest == NULL)`
583			`goto nla_put_failure;`
584
585			`NLA_PUT_U32(skb, CTRL_ATTR_MCAST_GRP_ID, grp->id);`
586			`NLA_PUT_STRING(skb, CTRL_ATTR_MCAST_GRP_NAME,`
587			`grp->name);`
588
589			`nla_nest_end(skb, nest);`
590			`nla_nest_end(skb, nla_grps);`
591
592			`return genlmsg_end(skb, hdr);`
593
594			`nla_put_failure:`
595			`return genlmsg_cancel(skb, hdr);`
596			`}`
597
598			`static int ctrl_dumpfamily(struct sk_buff skb, struct netlink_callback cb)`
599			`{`
600
601			`int i, n = 0;`
602			`struct genl_family *rt;`
603			`int chains_to_skip = cb->args[0];`
604			`int fams_to_skip = cb->args[1];`
605
606			`if (chains_to_skip != 0)`
607			`genl_lock();`
608
609			`for (i = 0; i < GENL_FAM_TAB_SIZE; i++) {`
610			`if (i < chains_to_skip)`
611			`continue;`
612			`n = 0;`
613			`list_for_each_entry(rt, genl_family_chain(i), family_list) {`
614			`if (++n < fams_to_skip)`
615			`continue;`
616			`if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).pid,`
617			`cb->nlh->nlmsg_seq, NLM_F_MULTI,`
618			`skb, CTRL_CMD_NEWFAMILY) < 0)`
619			`goto errout;`
620			`}`
621
622			`fams_to_skip = 0;`
623			`}`
624
625			`errout:`
626			`if (chains_to_skip != 0)`
627			`genl_unlock();`
628
629			`cb->args[0] = i;`
630			`cb->args[1] = n;`
631
632			`return skb->len;`
633			`}`
634
635			`static struct sk_buff ctrl_build_family_msg(struct genl_family family,`
636			`u32 pid, int seq, u8 cmd)`
637			`{`
638			`struct sk_buff *skb;`
639			`int err;`
640
641			`skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);`
642			`if (skb == NULL)`
643			`return ERR_PTR(-ENOBUFS);`
644
645			`err = ctrl_fill_info(family, pid, seq, 0, skb, cmd);`
646			`if (err < 0) {`
647			`nlmsg_free(skb);`
648			`return ERR_PTR(err);`
649			`}`
650
651			`return skb;`
652			`}`
653
654			`static struct sk_buff ctrl_build_mcgrp_msg(struct genl_multicast_group grp,`
655			`u32 pid, int seq, u8 cmd)`
656			`{`
657			`struct sk_buff *skb;`
658			`int err;`
659
660			`skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);`
661			`if (skb == NULL)`
662			`return ERR_PTR(-ENOBUFS);`
663
664			`err = ctrl_fill_mcgrp_info(grp, pid, seq, 0, skb, cmd);`
665			`if (err < 0) {`
666			`nlmsg_free(skb);`
667			`return ERR_PTR(err);`
668			`}`
669
670			`return skb;`
671			`}`
672
673			`static const struct nla_policy ctrl_policy[CTRL_ATTR_MAX+1] = {`
674			`[CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },`
675			`[CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,`
676			`.len = GENL_NAMSIZ - 1 },`
677			`};`
678
679			`static int ctrl_getfamily(struct sk_buff skb, struct genl_info info)`
680			`{`
681			`struct sk_buff *msg;`
682			`struct genl_family *res = NULL;`
683			`int err = -EINVAL;`
684
685			`if (info->attrs[CTRL_ATTR_FAMILY_ID]) {`
686			`u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);`
687			`res = genl_family_find_byid(id);`
688			`}`
689
690			`if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {`
691			`char *name;`
692
693			`name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);`
694			`res = genl_family_find_byname(name);`
695			`}`
696
697			`if (res == NULL) {`
698			`err = -ENOENT;`
699			`goto errout;`
700			`}`
701
702			`msg = ctrl_build_family_msg(res, info->snd_pid, info->snd_seq,`
703			`CTRL_CMD_NEWFAMILY);`
704			`if (IS_ERR(msg)) {`
705			`err = PTR_ERR(msg);`
706			`goto errout;`
707			`}`
708
709			`err = genlmsg_reply(msg, info);`
710			`errout:`
711			`return err;`
712			`}`
713
714			`static int genl_ctrl_event(int event, void *data)`
715			`{`
716			`struct sk_buff *msg;`
717
718			`if (genl_sock == NULL)`
719			`return 0;`
720
721			`switch (event) {`
722			`case CTRL_CMD_NEWFAMILY:`
723			`case CTRL_CMD_DELFAMILY:`
724			`msg = ctrl_build_family_msg(data, 0, 0, event);`
725			`if (IS_ERR(msg))`
726			`return PTR_ERR(msg);`
727
728			`genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);`
729			`break;`
730			`case CTRL_CMD_NEWMCAST_GRP:`
731			`case CTRL_CMD_DELMCAST_GRP:`
732			`msg = ctrl_build_mcgrp_msg(data, 0, 0, event);`
733			`if (IS_ERR(msg))`
734			`return PTR_ERR(msg);`
735
736			`genlmsg_multicast(msg, 0, GENL_ID_CTRL, GFP_KERNEL);`
737			`break;`
738			`}`
739
740			`return 0;`
741			`}`
742
743			`static struct genl_ops genl_ctrl_ops = {`
744			`.cmd = CTRL_CMD_GETFAMILY,`
745			`.doit = ctrl_getfamily,`
746			`.dumpit = ctrl_dumpfamily,`
747			`.policy = ctrl_policy,`
748			`};`
749
750			`static struct genl_multicast_group notify_grp = {`
751			`.name = "notify",`
752			`};`
753
754			`static int __init genl_init(void)`
755			`{`
756			`int i, err;`
757
758			`for (i = 0; i < GENL_FAM_TAB_SIZE; i++)`
759			`INIT_LIST_HEAD(&family_ht[i]);`
760
761			`err = genl_register_family(&genl_ctrl);`
762			`if (err < 0)`
763			`goto errout;`
764
765			`err = genl_register_ops(&genl_ctrl, &genl_ctrl_ops);`
766			`if (err < 0)`
767			`goto errout_register;`
768
769			`netlink_set_nonroot(NETLINK_GENERIC, NL_NONROOT_RECV);`
770
771			`/* we'll bump the group number right afterwards */`
772			`genl_sock = netlink_kernel_create(&init_net, NETLINK_GENERIC, 0,`
773			`genl_rcv, NULL, THIS_MODULE);`
774			`if (genl_sock == NULL)`
775			`panic("GENL: Cannot initialize generic netlink\n");`
776
777			`err = genl_register_mc_group(&genl_ctrl, &notify_grp);`
778			`if (err < 0)`
779			`goto errout_register;`
780
781			`return 0;`
782
783			`errout_register:`
784			`genl_unregister_family(&genl_ctrl);`
785			`errout:`
786			`panic("GENL: Cannot register controller: %d\n", err);`
787			`}`
788
789			`subsys_initcall(genl_init);`
790
791			`EXPORT_SYMBOL(genl_sock);`
792			`EXPORT_SYMBOL(genl_register_ops);`
793			`EXPORT_SYMBOL(genl_unregister_ops);`
794			`EXPORT_SYMBOL(genl_register_family);`
795			`EXPORT_SYMBOL(genl_unregister_family);`