// SPDX-License-Identifier: GPL-2.0-only

#include <net/sock.h>
#include <linux/ethtool_netlink.h>
#include <linux/pm_runtime.h>
#include "netlink.h"

static struct genl_family ethtool_genl_family;

static bool ethnl_ok __read_mostly;
static u32 ethnl_bcast_seq;

#define ETHTOOL_FLAGS_BASIC (ETHTOOL_FLAG_COMPACT_BITSETS |     \
                             ETHTOOL_FLAG_OMIT_REPLY)
#define ETHTOOL_FLAGS_STATS (ETHTOOL_FLAGS_BASIC | ETHTOOL_FLAG_STATS)

const struct nla_policy ethnl_header_policy[] = {
        [ETHTOOL_A_HEADER_DEV_INDEX]    = { .type = NLA_U32 },
        [ETHTOOL_A_HEADER_DEV_NAME]     = { .type = NLA_NUL_STRING,
                                            .len = ALTIFNAMSIZ - 1 },
        [ETHTOOL_A_HEADER_FLAGS]        = NLA_POLICY_MASK(NLA_U32,
                                                          ETHTOOL_FLAGS_BASIC),
};

const struct nla_policy ethnl_header_policy_stats[] = {
        [ETHTOOL_A_HEADER_DEV_INDEX]    = { .type = NLA_U32 },
        [ETHTOOL_A_HEADER_DEV_NAME]     = { .type = NLA_NUL_STRING,
                                            .len = ALTIFNAMSIZ - 1 },
        [ETHTOOL_A_HEADER_FLAGS]        = NLA_POLICY_MASK(NLA_U32,
                                                          ETHTOOL_FLAGS_STATS),
};

int ethnl_ops_begin(struct net_device *dev)
{
        int ret;

        if (!dev)
                return -ENODEV;

        if (dev->dev.parent)
                pm_runtime_get_sync(dev->dev.parent);

        if (!netif_device_present(dev)) {
                ret = -ENODEV;
                goto err;
        }

        if (dev->ethtool_ops->begin) {
                ret = dev->ethtool_ops->begin(dev);
                if (ret)
                        goto err;
        }

        return 0;
err:
        if (dev->dev.parent)
                pm_runtime_put(dev->dev.parent);

        return ret;
}

void ethnl_ops_complete(struct net_device *dev)
{
        if (dev->ethtool_ops->complete)
                dev->ethtool_ops->complete(dev);

        if (dev->dev.parent)
                pm_runtime_put(dev->dev.parent);
}

/**
 * ethnl_parse_header_dev_get() - parse request header
 * @req_info:    structure to put results into
 * @header:      nest attribute with request header
 * @net:         request netns
 * @extack:      netlink extack for error reporting
 * @require_dev: fail if no device identified in header
 *
 * Parse request header in nested attribute @nest and puts results into
 * the structure pointed to by @req_info. Extack from @info is used for error
 * reporting. If req_info->dev is not null on return, reference to it has
 * been taken. If error is returned, *req_info is null initialized and no
 * reference is held.
 *
 * Return: 0 on success or negative error code
 */
int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
                               const struct nlattr *header, struct net *net,
                               struct netlink_ext_ack *extack, bool require_dev)
{
        struct nlattr *tb[ARRAY_SIZE(ethnl_header_policy)];
        const struct nlattr *devname_attr;
        struct net_device *dev = NULL;
        u32 flags = 0;
        int ret;

        if (!header) {
                NL_SET_ERR_MSG(extack, "request header missing");
                return -EINVAL;
        }
        /* No validation here, command policy should have a nested policy set
         * for the header, therefore validation should have already been done.
         */
        ret = nla_parse_nested(tb, ARRAY_SIZE(ethnl_header_policy) - 1, header,
                               NULL, extack);
        if (ret < 0)
                return ret;
        if (tb[ETHTOOL_A_HEADER_FLAGS])
                flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);

        devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];
        if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
                u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);

                dev = dev_get_by_index(net, ifindex);
                if (!dev) {
                        NL_SET_ERR_MSG_ATTR(extack,
                                            tb[ETHTOOL_A_HEADER_DEV_INDEX],
                                            "no device matches ifindex");
                        return -ENODEV;
                }
                /* if both ifindex and ifname are passed, they must match */
                if (devname_attr &&
                    strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
                        dev_put(dev);
                        NL_SET_ERR_MSG_ATTR(extack, header,
                                            "ifindex and name do not match");
                        return -ENODEV;
                }
        } else if (devname_attr) {
                dev = dev_get_by_name(net, nla_data(devname_attr));
                if (!dev) {
                        NL_SET_ERR_MSG_ATTR(extack, devname_attr,
                                            "no device matches name");
                        return -ENODEV;
                }
        } else if (require_dev) {
                NL_SET_ERR_MSG_ATTR(extack, header,
                                    "neither ifindex nor name specified");
                return -EINVAL;
        }

        req_info->dev = dev;
        req_info->flags = flags;
        return 0;
}

/**
 * ethnl_fill_reply_header() - Put common header into a reply message
 * @skb:      skb with the message
 * @dev:      network device to describe in header
 * @attrtype: attribute type to use for the nest
 *
 * Create a nested attribute with attributes describing given network device.
 *
 * Return: 0 on success, error value (-EMSGSIZE only) on error
 */
int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
                            u16 attrtype)
{
        struct nlattr *nest;

        if (!dev)
                return 0;
        nest = nla_nest_start(skb, attrtype);
        if (!nest)
                return -EMSGSIZE;

        if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
            nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
                goto nla_put_failure;
        /* If more attributes are put into reply header, ethnl_header_size()
         * must be updated to account for them.
         */

        nla_nest_end(skb, nest);
        return 0;

nla_put_failure:
        nla_nest_cancel(skb, nest);
        return -EMSGSIZE;
}

/**
 * ethnl_reply_init() - Create skb for a reply and fill device identification
 * @payload:      payload length (without netlink and genetlink header)
 * @dev:          device the reply is about (may be null)
 * @cmd:          ETHTOOL_MSG_* message type for reply
 * @hdr_attrtype: attribute type for common header
 * @info:         genetlink info of the received packet we respond to
 * @ehdrp:        place to store payload pointer returned by genlmsg_new()
 *
 * Return: pointer to allocated skb on success, NULL on error
 */
struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
                                 u16 hdr_attrtype, struct genl_info *info,
                                 void **ehdrp)
{
        struct sk_buff *skb;

        skb = genlmsg_new(payload, GFP_KERNEL);
        if (!skb)
                goto err;
        *ehdrp = genlmsg_put_reply(skb, info, &ethtool_genl_family, 0, cmd);
        if (!*ehdrp)
                goto err_free;

        if (dev) {
                int ret;

                ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
                if (ret < 0)
                        goto err_free;
        }
        return skb;

err_free:
        nlmsg_free(skb);
err:
        if (info)
                GENL_SET_ERR_MSG(info, "failed to setup reply message");
        return NULL;
}

void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd)
{
        return genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
                           &ethtool_genl_family, 0, cmd);
}

void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
{
        return genlmsg_put(skb, 0, ++ethnl_bcast_seq, &ethtool_genl_family, 0,
                           cmd);
}

int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
{
        return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
                                       0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
}

/* GET request helpers */

/**
 * struct ethnl_dump_ctx - context structure for generic dumpit() callback
 * @ops:        request ops of currently processed message type
 * @req_info:   parsed request header of processed request
 * @reply_data: data needed to compose the reply
 * @pos_hash:   saved iteration position - hashbucket
 * @pos_idx:    saved iteration position - index
 *
 * These parameters are kept in struct netlink_callback as context preserved
 * between iterations. They are initialized by ethnl_default_start() and used
 * in ethnl_default_dumpit() and ethnl_default_done().
 */
struct ethnl_dump_ctx {
        const struct ethnl_request_ops  *ops;
        struct ethnl_req_info           *req_info;
        struct ethnl_reply_data         *reply_data;
        int                             pos_hash;
        int                             pos_idx;
};

static const struct ethnl_request_ops *
ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
        [ETHTOOL_MSG_STRSET_GET]        = &ethnl_strset_request_ops,
        [ETHTOOL_MSG_LINKINFO_GET]      = &ethnl_linkinfo_request_ops,
        [ETHTOOL_MSG_LINKMODES_GET]     = &ethnl_linkmodes_request_ops,
        [ETHTOOL_MSG_LINKSTATE_GET]     = &ethnl_linkstate_request_ops,
        [ETHTOOL_MSG_DEBUG_GET]         = &ethnl_debug_request_ops,
        [ETHTOOL_MSG_WOL_GET]           = &ethnl_wol_request_ops,
        [ETHTOOL_MSG_FEATURES_GET]      = &ethnl_features_request_ops,
        [ETHTOOL_MSG_PRIVFLAGS_GET]     = &ethnl_privflags_request_ops,
        [ETHTOOL_MSG_RINGS_GET]         = &ethnl_rings_request_ops,
        [ETHTOOL_MSG_CHANNELS_GET]      = &ethnl_channels_request_ops,
        [ETHTOOL_MSG_COALESCE_GET]      = &ethnl_coalesce_request_ops,
        [ETHTOOL_MSG_PAUSE_GET]         = &ethnl_pause_request_ops,
        [ETHTOOL_MSG_EEE_GET]           = &ethnl_eee_request_ops,
        [ETHTOOL_MSG_FEC_GET]           = &ethnl_fec_request_ops,
        [ETHTOOL_MSG_TSINFO_GET]        = &ethnl_tsinfo_request_ops,
        [ETHTOOL_MSG_MODULE_EEPROM_GET] = &ethnl_module_eeprom_request_ops,
        [ETHTOOL_MSG_STATS_GET]         = &ethnl_stats_request_ops,
        [ETHTOOL_MSG_PHC_VCLOCKS_GET]   = &ethnl_phc_vclocks_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
{
        return (struct ethnl_dump_ctx *)cb->ctx;
}

/**
 * ethnl_default_parse() - Parse request message
 * @req_info:    pointer to structure to put data into
 * @tb:          parsed attributes
 * @net:         request netns
 * @request_ops: struct request_ops for request type
 * @extack:      netlink extack for error reporting
 * @require_dev: fail if no device identified in header
 *
 * Parse universal request header and call request specific ->parse_request()
 * callback (if defined) to parse the rest of the message.
 *
 * Return: 0 on success or negative error code
 */
static int ethnl_default_parse(struct ethnl_req_info *req_info,
                               struct nlattr **tb, struct net *net,
                               const struct ethnl_request_ops *request_ops,
                               struct netlink_ext_ack *extack, bool require_dev)
{
        int ret;

        ret = ethnl_parse_header_dev_get(req_info, tb[request_ops->hdr_attr],
                                         net, extack, require_dev);
        if (ret < 0)
                return ret;

        if (request_ops->parse_request) {
                ret = request_ops->parse_request(req_info, tb, extack);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

/**
 * ethnl_init_reply_data() - Initialize reply data for GET request
 * @reply_data: pointer to embedded struct ethnl_reply_data
 * @ops:        instance of struct ethnl_request_ops describing the layout
 * @dev:        network device to initialize the reply for
 *
 * Fills the reply data part with zeros and sets the dev member. Must be called
 * before calling the ->fill_reply() callback (for each iteration when handling
 * dump requests).
 */
static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
                                  const struct ethnl_request_ops *ops,
                                  struct net_device *dev)
{
        memset(reply_data, 0, ops->reply_data_size);
        reply_data->dev = dev;
}

/* default ->doit() handler for GET type requests */
static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
{
        struct ethnl_reply_data *reply_data = NULL;
        struct ethnl_req_info *req_info = NULL;
        const u8 cmd = info->genlhdr->cmd;
        const struct ethnl_request_ops *ops;
        int hdr_len, reply_len;
        struct sk_buff *rskb;
        void *reply_payload;
        int ret;

        ops = ethnl_default_requests[cmd];
        if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
                return -EOPNOTSUPP;
        req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
        if (!req_info)
                return -ENOMEM;
        reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
        if (!reply_data) {
                kfree(req_info);
                return -ENOMEM;
        }

        ret = ethnl_default_parse(req_info, info->attrs, genl_info_net(info),
                                  ops, info->extack, !ops->allow_nodev_do);
        if (ret < 0)
                goto err_dev;
        ethnl_init_reply_data(reply_data, ops, req_info->dev);

        rtnl_lock();
        ret = ops->prepare_data(req_info, reply_data, info);
        rtnl_unlock();
        if (ret < 0)
                goto err_cleanup;
        ret = ops->reply_size(req_info, reply_data);
        if (ret < 0)
                goto err_cleanup;
        reply_len = ret;
        ret = -ENOMEM;
        rskb = ethnl_reply_init(reply_len + ethnl_reply_header_size(),
                                req_info->dev, ops->reply_cmd,
                                ops->hdr_attr, info, &reply_payload);
        if (!rskb)
                goto err_cleanup;
        hdr_len = rskb->len;
        ret = ops->fill_reply(rskb, req_info, reply_data);
        if (ret < 0)
                goto err_msg;
        WARN_ONCE(rskb->len - hdr_len > reply_len,
                  "ethnl cmd %d: calculated reply length %d, but consumed %d\n",
                  cmd, reply_len, rskb->len - hdr_len);
        if (ops->cleanup_data)
                ops->cleanup_data(reply_data);

        genlmsg_end(rskb, reply_payload);
        dev_put(req_info->dev);
        kfree(reply_data);
        kfree(req_info);
        return genlmsg_reply(rskb, info);

err_msg:
        WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
        nlmsg_free(rskb);
err_cleanup:
        if (ops->cleanup_data)
                ops->cleanup_data(reply_data);
err_dev:
        dev_put(req_info->dev);
        kfree(reply_data);
        kfree(req_info);
        return ret;
}

static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
                                  const struct ethnl_dump_ctx *ctx,
                                  struct netlink_callback *cb)
{
        void *ehdr;
        int ret;

        ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
                           &ethtool_genl_family, NLM_F_MULTI,
                           ctx->ops->reply_cmd);
        if (!ehdr)
                return -EMSGSIZE;

        ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
        rtnl_lock();
        ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
        rtnl_unlock();
        if (ret < 0)
                goto out;
        ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
        if (ret < 0)
                goto out;
        ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);

out:
        if (ctx->ops->cleanup_data)
                ctx->ops->cleanup_data(ctx->reply_data);
        ctx->reply_data->dev = NULL;
        if (ret < 0)
                genlmsg_cancel(skb, ehdr);
        else
                genlmsg_end(skb, ehdr);
        return ret;
}

/* Default ->dumpit() handler for GET requests. Device iteration copied from
 * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
 * persistence as we cannot guarantee to hold RTNL lock through the whole
 * function as rtnetnlink does.
 */
static int ethnl_default_dumpit(struct sk_buff *skb,
                                struct netlink_callback *cb)
{
        struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
        struct net *net = sock_net(skb->sk);
        int s_idx = ctx->pos_idx;
        int h, idx = 0;
        int ret = 0;

        rtnl_lock();
        for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
                struct hlist_head *head;
                struct net_device *dev;
                unsigned int seq;

                head = &net->dev_index_head[h];

restart_chain:
                seq = net->dev_base_seq;
                cb->seq = seq;
                idx = 0;
                hlist_for_each_entry(dev, head, index_hlist) {
                        if (idx < s_idx)
                                goto cont;
                        dev_hold(dev);
                        rtnl_unlock();

                        ret = ethnl_default_dump_one(skb, dev, ctx, cb);
                        dev_put(dev);
                        if (ret < 0) {
                                if (ret == -EOPNOTSUPP)
                                        goto lock_and_cont;
                                if (likely(skb->len))
                                        ret = skb->len;
                                goto out;
                        }
lock_and_cont:
                        rtnl_lock();
                        if (net->dev_base_seq != seq) {
                                s_idx = idx + 1;
                                goto restart_chain;
                        }
cont:
                        idx++;
                }

        }
        rtnl_unlock();

out:
        ctx->pos_hash = h;
        ctx->pos_idx = idx;
        nl_dump_check_consistent(cb, nlmsg_hdr(skb));

        return ret;
}

/* generic ->start() handler for GET requests */
static int ethnl_default_start(struct netlink_callback *cb)
{
        const struct genl_dumpit_info *info = genl_dumpit_info(cb);
        struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
        struct ethnl_reply_data *reply_data;
        const struct ethnl_request_ops *ops;
        struct ethnl_req_info *req_info;
        struct genlmsghdr *ghdr;
        int ret;

        BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));

        ghdr = nlmsg_data(cb->nlh);
        ops = ethnl_default_requests[ghdr->cmd];
        if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
                return -EOPNOTSUPP;
        req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
        if (!req_info)
                return -ENOMEM;
        reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
        if (!reply_data) {
                ret = -ENOMEM;
                goto free_req_info;
        }

        ret = ethnl_default_parse(req_info, info->attrs, sock_net(cb->skb->sk),
                                  ops, cb->extack, false);
        if (req_info->dev) {
                /* We ignore device specification in dump requests but as the
                 * same parser as for non-dump (doit) requests is used, it
                 * would take reference to the device if it finds one
                 */
                dev_put(req_info->dev);
                req_info->dev = NULL;
        }
        if (ret < 0)
                goto free_reply_data;

        ctx->ops = ops;
        ctx->req_info = req_info;
        ctx->reply_data = reply_data;
        ctx->pos_hash = 0;
        ctx->pos_idx = 0;

        return 0;

free_reply_data:
        kfree(reply_data);
free_req_info:
        kfree(req_info);

        return ret;
}

/* default ->done() handler for GET requests */
static int ethnl_default_done(struct netlink_callback *cb)
{
        struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);

        kfree(ctx->reply_data);
        kfree(ctx->req_info);

        return 0;
}

static const struct ethnl_request_ops *
ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
        [ETHTOOL_MSG_LINKINFO_NTF]      = &ethnl_linkinfo_request_ops,
        [ETHTOOL_MSG_LINKMODES_NTF]     = &ethnl_linkmodes_request_ops,
        [ETHTOOL_MSG_DEBUG_NTF]         = &ethnl_debug_request_ops,
        [ETHTOOL_MSG_WOL_NTF]           = &ethnl_wol_request_ops,
        [ETHTOOL_MSG_FEATURES_NTF]      = &ethnl_features_request_ops,
        [ETHTOOL_MSG_PRIVFLAGS_NTF]     = &ethnl_privflags_request_ops,
        [ETHTOOL_MSG_RINGS_NTF]         = &ethnl_rings_request_ops,
        [ETHTOOL_MSG_CHANNELS_NTF]      = &ethnl_channels_request_ops,
        [ETHTOOL_MSG_COALESCE_NTF]      = &ethnl_coalesce_request_ops,
        [ETHTOOL_MSG_PAUSE_NTF]         = &ethnl_pause_request_ops,
        [ETHTOOL_MSG_EEE_NTF]           = &ethnl_eee_request_ops,
        [ETHTOOL_MSG_FEC_NTF]           = &ethnl_fec_request_ops,
};

/* default notification handler */
static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
                                 const void *data)
{
        struct ethnl_reply_data *reply_data;
        const struct ethnl_request_ops *ops;
        struct ethnl_req_info *req_info;
        struct sk_buff *skb;
        void *reply_payload;
        int reply_len;
        int ret;

        if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
                      !ethnl_default_notify_ops[cmd],
                      "unexpected notification type %u\n", cmd))
                return;
        ops = ethnl_default_notify_ops[cmd];
        req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
        if (!req_info)
                return;
        reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
        if (!reply_data) {
                kfree(req_info);
                return;
        }

        req_info->dev = dev;
        req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;

        ethnl_init_reply_data(reply_data, ops, dev);
        ret = ops->prepare_data(req_info, reply_data, NULL);
        if (ret < 0)
                goto err_cleanup;
        ret = ops->reply_size(req_info, reply_data);
        if (ret < 0)
                goto err_cleanup;
        reply_len = ret + ethnl_reply_header_size();
        ret = -ENOMEM;
        skb = genlmsg_new(reply_len, GFP_KERNEL);
        if (!skb)
                goto err_cleanup;
        reply_payload = ethnl_bcastmsg_put(skb, cmd);
        if (!reply_payload)
                goto err_skb;
        ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
        if (ret < 0)
                goto err_msg;
        ret = ops->fill_reply(skb, req_info, reply_data);
        if (ret < 0)
                goto err_msg;
        if (ops->cleanup_data)
                ops->cleanup_data(reply_data);

        genlmsg_end(skb, reply_payload);
        kfree(reply_data);
        kfree(req_info);
        ethnl_multicast(skb, dev);
        return;

err_msg:
        WARN_ONCE(ret == -EMSGSIZE,
                  "calculated message payload length (%d) not sufficient\n",
                  reply_len);
err_skb:
        nlmsg_free(skb);
err_cleanup:
        if (ops->cleanup_data)
                ops->cleanup_data(reply_data);
        kfree(reply_data);
        kfree(req_info);
        return;
}

/* notifications */

typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
                                       const void *data);

static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
        [ETHTOOL_MSG_LINKINFO_NTF]      = ethnl_default_notify,
        [ETHTOOL_MSG_LINKMODES_NTF]     = ethnl_default_notify,
        [ETHTOOL_MSG_DEBUG_NTF]         = ethnl_default_notify,
        [ETHTOOL_MSG_WOL_NTF]           = ethnl_default_notify,
        [ETHTOOL_MSG_FEATURES_NTF]      = ethnl_default_notify,
        [ETHTOOL_MSG_PRIVFLAGS_NTF]     = ethnl_default_notify,
        [ETHTOOL_MSG_RINGS_NTF]         = ethnl_default_notify,
        [ETHTOOL_MSG_CHANNELS_NTF]      = ethnl_default_notify,
        [ETHTOOL_MSG_COALESCE_NTF]      = ethnl_default_notify,
        [ETHTOOL_MSG_PAUSE_NTF]         = ethnl_default_notify,
        [ETHTOOL_MSG_EEE_NTF]           = ethnl_default_notify,
        [ETHTOOL_MSG_FEC_NTF]           = ethnl_default_notify,
};

void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
{
        if (unlikely(!ethnl_ok))
                return;
        ASSERT_RTNL();

        if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
                   ethnl_notify_handlers[cmd]))
                ethnl_notify_handlers[cmd](dev, cmd, data);
        else
                WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
                          cmd, netdev_name(dev));
}
EXPORT_SYMBOL(ethtool_notify);

static void ethnl_notify_features(struct netdev_notifier_info *info)
{
        struct net_device *dev = netdev_notifier_info_to_dev(info);

        ethtool_notify(dev, ETHTOOL_MSG_FEATURES_NTF, NULL);
}

static int ethnl_netdev_event(struct notifier_block *this, unsigned long event,
                              void *ptr)
{
        switch (event) {
        case NETDEV_FEAT_CHANGE:
                ethnl_notify_features(ptr);
                break;
        }

        return NOTIFY_DONE;
}

static struct notifier_block ethnl_netdev_notifier = {
        .notifier_call = ethnl_netdev_event,
};

/* genetlink setup */

static const struct genl_ops ethtool_genl_ops[] = {
        {
                .cmd    = ETHTOOL_MSG_STRSET_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_strset_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_strset_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_LINKINFO_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_linkinfo_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_linkinfo_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_LINKINFO_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_linkinfo,
                .policy = ethnl_linkinfo_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_linkinfo_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_LINKMODES_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_linkmodes_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_linkmodes_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_LINKMODES_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_linkmodes,
                .policy = ethnl_linkmodes_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_linkmodes_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_LINKSTATE_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_linkstate_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_linkstate_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_DEBUG_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_debug_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_debug_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_DEBUG_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_debug,
                .policy = ethnl_debug_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_debug_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_WOL_GET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_wol_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_wol_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_WOL_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_wol,
                .policy = ethnl_wol_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_wol_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_FEATURES_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_features_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_features_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_FEATURES_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_features,
                .policy = ethnl_features_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_features_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_PRIVFLAGS_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_privflags_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_privflags_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_PRIVFLAGS_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_privflags,
                .policy = ethnl_privflags_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_privflags_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_RINGS_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_rings_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_rings_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_RINGS_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_rings,
                .policy = ethnl_rings_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_rings_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_CHANNELS_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_channels_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_channels_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_CHANNELS_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_channels,
                .policy = ethnl_channels_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_channels_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_COALESCE_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_coalesce_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_coalesce_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_COALESCE_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_coalesce,
                .policy = ethnl_coalesce_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_coalesce_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_PAUSE_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_pause_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_pause_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_PAUSE_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_pause,
                .policy = ethnl_pause_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_pause_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_EEE_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_eee_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_eee_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_EEE_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_eee,
                .policy = ethnl_eee_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_eee_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_TSINFO_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_tsinfo_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_tsinfo_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_CABLE_TEST_ACT,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_act_cable_test,
                .policy = ethnl_cable_test_act_policy,
                .maxattr = ARRAY_SIZE(ethnl_cable_test_act_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_CABLE_TEST_TDR_ACT,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_act_cable_test_tdr,
                .policy = ethnl_cable_test_tdr_act_policy,
                .maxattr = ARRAY_SIZE(ethnl_cable_test_tdr_act_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_TUNNEL_INFO_GET,
                .doit   = ethnl_tunnel_info_doit,
                .start  = ethnl_tunnel_info_start,
                .dumpit = ethnl_tunnel_info_dumpit,
                .policy = ethnl_tunnel_info_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_tunnel_info_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_FEC_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_fec_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_fec_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_FEC_SET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_fec,
                .policy = ethnl_fec_set_policy,
                .maxattr = ARRAY_SIZE(ethnl_fec_set_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_MODULE_EEPROM_GET,
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_module_eeprom_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_module_eeprom_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_STATS_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_stats_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_stats_get_policy) - 1,
        },
        {
                .cmd    = ETHTOOL_MSG_PHC_VCLOCKS_GET,
                .doit   = ethnl_default_doit,
                .start  = ethnl_default_start,
                .dumpit = ethnl_default_dumpit,
                .done   = ethnl_default_done,
                .policy = ethnl_phc_vclocks_get_policy,
                .maxattr = ARRAY_SIZE(ethnl_phc_vclocks_get_policy) - 1,

        },
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
        [ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
};

static struct genl_family ethtool_genl_family __ro_after_init = {
        .name           = ETHTOOL_GENL_NAME,
        .version        = ETHTOOL_GENL_VERSION,
        .netnsok        = true,
        .parallel_ops   = true,
        .ops            = ethtool_genl_ops,
        .n_ops          = ARRAY_SIZE(ethtool_genl_ops),
        .mcgrps         = ethtool_nl_mcgrps,
        .n_mcgrps       = ARRAY_SIZE(ethtool_nl_mcgrps),
};

/* module setup */

static int __init ethnl_init(void)
{
        int ret;

        ret = genl_register_family(&ethtool_genl_family);
        if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
                return ret;
        ethnl_ok = true;

        ret = register_netdevice_notifier(&ethnl_netdev_notifier);
        WARN(ret < 0, "ethtool: net device notifier registration failed");
        return ret;
}

subsys_initcall(ethnl_init);