1 // SPDX-License-Identifier: GPL-2.0-only
4 #include <linux/ethtool_netlink.h>
7 static struct genl_family ethtool_genl_family;
9 static bool ethnl_ok __read_mostly;
10 static u32 ethnl_bcast_seq;
12 static const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_MAX + 1] = {
13 [ETHTOOL_A_HEADER_UNSPEC] = { .type = NLA_REJECT },
14 [ETHTOOL_A_HEADER_DEV_INDEX] = { .type = NLA_U32 },
15 [ETHTOOL_A_HEADER_DEV_NAME] = { .type = NLA_NUL_STRING,
16 .len = ALTIFNAMSIZ - 1 },
17 [ETHTOOL_A_HEADER_FLAGS] = { .type = NLA_U32 },
21 * ethnl_parse_header() - parse request header
22 * @req_info: structure to put results into
23 * @header: nest attribute with request header
25 * @extack: netlink extack for error reporting
26 * @require_dev: fail if no device identified in header
28 * Parse request header in nested attribute @nest and puts results into
29 * the structure pointed to by @req_info. Extack from @info is used for error
30 * reporting. If req_info->dev is not null on return, reference to it has
31 * been taken. If error is returned, *req_info is null initialized and no
34 * Return: 0 on success or negative error code
36 int ethnl_parse_header(struct ethnl_req_info *req_info,
37 const struct nlattr *header, struct net *net,
38 struct netlink_ext_ack *extack, bool require_dev)
40 struct nlattr *tb[ETHTOOL_A_HEADER_MAX + 1];
41 const struct nlattr *devname_attr;
42 struct net_device *dev = NULL;
47 NL_SET_ERR_MSG(extack, "request header missing");
50 ret = nla_parse_nested(tb, ETHTOOL_A_HEADER_MAX, header,
51 ethnl_header_policy, extack);
54 if (tb[ETHTOOL_A_HEADER_FLAGS]) {
55 flags = nla_get_u32(tb[ETHTOOL_A_HEADER_FLAGS]);
56 if (flags & ~ETHTOOL_FLAG_ALL) {
57 NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_HEADER_FLAGS],
58 "unrecognized request flags");
59 nl_set_extack_cookie_u32(extack, ETHTOOL_FLAG_ALL);
64 devname_attr = tb[ETHTOOL_A_HEADER_DEV_NAME];
65 if (tb[ETHTOOL_A_HEADER_DEV_INDEX]) {
66 u32 ifindex = nla_get_u32(tb[ETHTOOL_A_HEADER_DEV_INDEX]);
68 dev = dev_get_by_index(net, ifindex);
70 NL_SET_ERR_MSG_ATTR(extack,
71 tb[ETHTOOL_A_HEADER_DEV_INDEX],
72 "no device matches ifindex");
75 /* if both ifindex and ifname are passed, they must match */
77 strncmp(dev->name, nla_data(devname_attr), IFNAMSIZ)) {
79 NL_SET_ERR_MSG_ATTR(extack, header,
80 "ifindex and name do not match");
83 } else if (devname_attr) {
84 dev = dev_get_by_name(net, nla_data(devname_attr));
86 NL_SET_ERR_MSG_ATTR(extack, devname_attr,
87 "no device matches name");
90 } else if (require_dev) {
91 NL_SET_ERR_MSG_ATTR(extack, header,
92 "neither ifindex nor name specified");
96 if (dev && !netif_device_present(dev)) {
98 NL_SET_ERR_MSG(extack, "device not present");
103 req_info->flags = flags;
108 * ethnl_fill_reply_header() - Put common header into a reply message
109 * @skb: skb with the message
110 * @dev: network device to describe in header
111 * @attrtype: attribute type to use for the nest
113 * Create a nested attribute with attributes describing given network device.
115 * Return: 0 on success, error value (-EMSGSIZE only) on error
117 int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev,
124 nest = nla_nest_start(skb, attrtype);
128 if (nla_put_u32(skb, ETHTOOL_A_HEADER_DEV_INDEX, (u32)dev->ifindex) ||
129 nla_put_string(skb, ETHTOOL_A_HEADER_DEV_NAME, dev->name))
130 goto nla_put_failure;
131 /* If more attributes are put into reply header, ethnl_header_size()
132 * must be updated to account for them.
135 nla_nest_end(skb, nest);
139 nla_nest_cancel(skb, nest);
144 * ethnl_reply_init() - Create skb for a reply and fill device identification
145 * @payload: payload length (without netlink and genetlink header)
146 * @dev: device the reply is about (may be null)
147 * @cmd: ETHTOOL_MSG_* message type for reply
148 * @hdr_attrtype: attribute type for common header
149 * @info: genetlink info of the received packet we respond to
150 * @ehdrp: place to store payload pointer returned by genlmsg_new()
152 * Return: pointer to allocated skb on success, NULL on error
154 struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
155 u16 hdr_attrtype, struct genl_info *info,
160 skb = genlmsg_new(payload, GFP_KERNEL);
163 *ehdrp = genlmsg_put_reply(skb, info, ðtool_genl_family, 0, cmd);
170 ret = ethnl_fill_reply_header(skb, dev, hdr_attrtype);
180 GENL_SET_ERR_MSG(info, "failed to setup reply message");
184 static void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
186 return genlmsg_put(skb, 0, ++ethnl_bcast_seq, ðtool_genl_family, 0,
190 static int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
192 return genlmsg_multicast_netns(ðtool_genl_family, dev_net(dev), skb,
193 0, ETHNL_MCGRP_MONITOR, GFP_KERNEL);
196 /* GET request helpers */
199 * struct ethnl_dump_ctx - context structure for generic dumpit() callback
200 * @ops: request ops of currently processed message type
201 * @req_info: parsed request header of processed request
202 * @reply_data: data needed to compose the reply
203 * @pos_hash: saved iteration position - hashbucket
204 * @pos_idx: saved iteration position - index
206 * These parameters are kept in struct netlink_callback as context preserved
207 * between iterations. They are initialized by ethnl_default_start() and used
208 * in ethnl_default_dumpit() and ethnl_default_done().
210 struct ethnl_dump_ctx {
211 const struct ethnl_request_ops *ops;
212 struct ethnl_req_info *req_info;
213 struct ethnl_reply_data *reply_data;
218 static const struct ethnl_request_ops *
219 ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
220 [ETHTOOL_MSG_STRSET_GET] = ðnl_strset_request_ops,
221 [ETHTOOL_MSG_LINKINFO_GET] = ðnl_linkinfo_request_ops,
222 [ETHTOOL_MSG_LINKMODES_GET] = ðnl_linkmodes_request_ops,
223 [ETHTOOL_MSG_LINKSTATE_GET] = ðnl_linkstate_request_ops,
224 [ETHTOOL_MSG_DEBUG_GET] = ðnl_debug_request_ops,
225 [ETHTOOL_MSG_WOL_GET] = ðnl_wol_request_ops,
228 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
230 return (struct ethnl_dump_ctx *)cb->ctx;
234 * ethnl_default_parse() - Parse request message
235 * @req_info: pointer to structure to put data into
236 * @nlhdr: pointer to request message header
237 * @net: request netns
238 * @request_ops: struct request_ops for request type
239 * @extack: netlink extack for error reporting
240 * @require_dev: fail if no device identified in header
242 * Parse universal request header and call request specific ->parse_request()
243 * callback (if defined) to parse the rest of the message.
245 * Return: 0 on success or negative error code
247 static int ethnl_default_parse(struct ethnl_req_info *req_info,
248 const struct nlmsghdr *nlhdr, struct net *net,
249 const struct ethnl_request_ops *request_ops,
250 struct netlink_ext_ack *extack, bool require_dev)
255 tb = kmalloc_array(request_ops->max_attr + 1, sizeof(tb[0]),
260 ret = nlmsg_parse(nlhdr, GENL_HDRLEN, tb, request_ops->max_attr,
261 request_ops->request_policy, extack);
264 ret = ethnl_parse_header(req_info, tb[request_ops->hdr_attr], net,
265 extack, require_dev);
269 if (request_ops->parse_request) {
270 ret = request_ops->parse_request(req_info, tb, extack);
282 * ethnl_init_reply_data() - Initialize reply data for GET request
283 * @reply_data: pointer to embedded struct ethnl_reply_data
284 * @ops: instance of struct ethnl_request_ops describing the layout
285 * @dev: network device to initialize the reply for
287 * Fills the reply data part with zeros and sets the dev member. Must be called
288 * before calling the ->fill_reply() callback (for each iteration when handling
291 static void ethnl_init_reply_data(struct ethnl_reply_data *reply_data,
292 const struct ethnl_request_ops *ops,
293 struct net_device *dev)
295 memset(reply_data, 0, ops->reply_data_size);
296 reply_data->dev = dev;
299 /* default ->doit() handler for GET type requests */
300 static int ethnl_default_doit(struct sk_buff *skb, struct genl_info *info)
302 struct ethnl_reply_data *reply_data = NULL;
303 struct ethnl_req_info *req_info = NULL;
304 const u8 cmd = info->genlhdr->cmd;
305 const struct ethnl_request_ops *ops;
306 struct sk_buff *rskb;
311 ops = ethnl_default_requests[cmd];
312 if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", cmd))
314 req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
317 reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
323 ret = ethnl_default_parse(req_info, info->nlhdr, genl_info_net(info), ops,
324 info->extack, !ops->allow_nodev_do);
327 ethnl_init_reply_data(reply_data, ops, req_info->dev);
330 ret = ops->prepare_data(req_info, reply_data, info);
334 ret = ops->reply_size(req_info, reply_data);
339 rskb = ethnl_reply_init(reply_len, req_info->dev, ops->reply_cmd,
340 ops->hdr_attr, info, &reply_payload);
343 ret = ops->fill_reply(rskb, req_info, reply_data);
346 if (ops->cleanup_data)
347 ops->cleanup_data(reply_data);
349 genlmsg_end(rskb, reply_payload);
351 dev_put(req_info->dev);
354 return genlmsg_reply(rskb, info);
357 WARN_ONCE(ret == -EMSGSIZE, "calculated message payload length (%d) not sufficient\n", reply_len);
360 if (ops->cleanup_data)
361 ops->cleanup_data(reply_data);
364 dev_put(req_info->dev);
370 static int ethnl_default_dump_one(struct sk_buff *skb, struct net_device *dev,
371 const struct ethnl_dump_ctx *ctx)
375 ethnl_init_reply_data(ctx->reply_data, ctx->ops, dev);
377 ret = ctx->ops->prepare_data(ctx->req_info, ctx->reply_data, NULL);
381 ret = ethnl_fill_reply_header(skb, dev, ctx->ops->hdr_attr);
384 ret = ctx->ops->fill_reply(skb, ctx->req_info, ctx->reply_data);
387 if (ctx->ops->cleanup_data)
388 ctx->ops->cleanup_data(ctx->reply_data);
389 ctx->reply_data->dev = NULL;
393 /* Default ->dumpit() handler for GET requests. Device iteration copied from
394 * rtnl_dump_ifinfo(); we have to be more careful about device hashtable
395 * persistence as we cannot guarantee to hold RTNL lock through the whole
396 * function as rtnetnlink does.
398 static int ethnl_default_dumpit(struct sk_buff *skb,
399 struct netlink_callback *cb)
401 struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
402 struct net *net = sock_net(skb->sk);
403 int s_idx = ctx->pos_idx;
409 for (h = ctx->pos_hash; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
410 struct hlist_head *head;
411 struct net_device *dev;
414 head = &net->dev_index_head[h];
417 seq = net->dev_base_seq;
420 hlist_for_each_entry(dev, head, index_hlist) {
426 ehdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
428 ðtool_genl_family, 0,
429 ctx->ops->reply_cmd);
435 ret = ethnl_default_dump_one(skb, dev, ctx);
438 genlmsg_cancel(skb, ehdr);
439 if (ret == -EOPNOTSUPP)
441 if (likely(skb->len))
445 genlmsg_end(skb, ehdr);
448 if (net->dev_base_seq != seq) {
462 nl_dump_check_consistent(cb, nlmsg_hdr(skb));
467 /* generic ->start() handler for GET requests */
468 static int ethnl_default_start(struct netlink_callback *cb)
470 struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
471 struct ethnl_reply_data *reply_data;
472 const struct ethnl_request_ops *ops;
473 struct ethnl_req_info *req_info;
474 struct genlmsghdr *ghdr;
477 BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
479 ghdr = nlmsg_data(cb->nlh);
480 ops = ethnl_default_requests[ghdr->cmd];
481 if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))
483 req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
486 reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
492 ret = ethnl_default_parse(req_info, cb->nlh, sock_net(cb->skb->sk), ops,
495 /* We ignore device specification in dump requests but as the
496 * same parser as for non-dump (doit) requests is used, it
497 * would take reference to the device if it finds one
499 dev_put(req_info->dev);
500 req_info->dev = NULL;
503 goto free_reply_data;
506 ctx->req_info = req_info;
507 ctx->reply_data = reply_data;
521 /* default ->done() handler for GET requests */
522 static int ethnl_default_done(struct netlink_callback *cb)
524 struct ethnl_dump_ctx *ctx = ethnl_dump_context(cb);
526 kfree(ctx->reply_data);
527 kfree(ctx->req_info);
532 static const struct ethnl_request_ops *
533 ethnl_default_notify_ops[ETHTOOL_MSG_KERNEL_MAX + 1] = {
534 [ETHTOOL_MSG_LINKINFO_NTF] = ðnl_linkinfo_request_ops,
535 [ETHTOOL_MSG_LINKMODES_NTF] = ðnl_linkmodes_request_ops,
536 [ETHTOOL_MSG_DEBUG_NTF] = ðnl_debug_request_ops,
537 [ETHTOOL_MSG_WOL_NTF] = ðnl_wol_request_ops,
540 /* default notification handler */
541 static void ethnl_default_notify(struct net_device *dev, unsigned int cmd,
544 struct ethnl_reply_data *reply_data;
545 const struct ethnl_request_ops *ops;
546 struct ethnl_req_info *req_info;
552 if (WARN_ONCE(cmd > ETHTOOL_MSG_KERNEL_MAX ||
553 !ethnl_default_notify_ops[cmd],
554 "unexpected notification type %u\n", cmd))
556 ops = ethnl_default_notify_ops[cmd];
557 req_info = kzalloc(ops->req_info_size, GFP_KERNEL);
560 reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);
567 req_info->flags |= ETHTOOL_FLAG_COMPACT_BITSETS;
569 ethnl_init_reply_data(reply_data, ops, dev);
570 ret = ops->prepare_data(req_info, reply_data, NULL);
573 ret = ops->reply_size(req_info, reply_data);
578 skb = genlmsg_new(reply_len, GFP_KERNEL);
581 reply_payload = ethnl_bcastmsg_put(skb, cmd);
584 ret = ethnl_fill_reply_header(skb, dev, ops->hdr_attr);
587 ret = ops->fill_reply(skb, req_info, reply_data);
590 if (ops->cleanup_data)
591 ops->cleanup_data(reply_data);
593 genlmsg_end(skb, reply_payload);
596 ethnl_multicast(skb, dev);
600 WARN_ONCE(ret == -EMSGSIZE,
601 "calculated message payload length (%d) not sufficient\n",
606 if (ops->cleanup_data)
607 ops->cleanup_data(reply_data);
615 typedef void (*ethnl_notify_handler_t)(struct net_device *dev, unsigned int cmd,
618 static const ethnl_notify_handler_t ethnl_notify_handlers[] = {
619 [ETHTOOL_MSG_LINKINFO_NTF] = ethnl_default_notify,
620 [ETHTOOL_MSG_LINKMODES_NTF] = ethnl_default_notify,
621 [ETHTOOL_MSG_DEBUG_NTF] = ethnl_default_notify,
622 [ETHTOOL_MSG_WOL_NTF] = ethnl_default_notify,
625 void ethtool_notify(struct net_device *dev, unsigned int cmd, const void *data)
627 if (unlikely(!ethnl_ok))
631 if (likely(cmd < ARRAY_SIZE(ethnl_notify_handlers) &&
632 ethnl_notify_handlers[cmd]))
633 ethnl_notify_handlers[cmd](dev, cmd, data);
635 WARN_ONCE(1, "notification %u not implemented (dev=%s)\n",
636 cmd, netdev_name(dev));
638 EXPORT_SYMBOL(ethtool_notify);
640 /* genetlink setup */
642 static const struct genl_ops ethtool_genl_ops[] = {
644 .cmd = ETHTOOL_MSG_STRSET_GET,
645 .doit = ethnl_default_doit,
646 .start = ethnl_default_start,
647 .dumpit = ethnl_default_dumpit,
648 .done = ethnl_default_done,
651 .cmd = ETHTOOL_MSG_LINKINFO_GET,
652 .doit = ethnl_default_doit,
653 .start = ethnl_default_start,
654 .dumpit = ethnl_default_dumpit,
655 .done = ethnl_default_done,
658 .cmd = ETHTOOL_MSG_LINKINFO_SET,
659 .flags = GENL_UNS_ADMIN_PERM,
660 .doit = ethnl_set_linkinfo,
663 .cmd = ETHTOOL_MSG_LINKMODES_GET,
664 .doit = ethnl_default_doit,
665 .start = ethnl_default_start,
666 .dumpit = ethnl_default_dumpit,
667 .done = ethnl_default_done,
670 .cmd = ETHTOOL_MSG_LINKMODES_SET,
671 .flags = GENL_UNS_ADMIN_PERM,
672 .doit = ethnl_set_linkmodes,
675 .cmd = ETHTOOL_MSG_LINKSTATE_GET,
676 .doit = ethnl_default_doit,
677 .start = ethnl_default_start,
678 .dumpit = ethnl_default_dumpit,
679 .done = ethnl_default_done,
682 .cmd = ETHTOOL_MSG_DEBUG_GET,
683 .doit = ethnl_default_doit,
684 .start = ethnl_default_start,
685 .dumpit = ethnl_default_dumpit,
686 .done = ethnl_default_done,
689 .cmd = ETHTOOL_MSG_DEBUG_SET,
690 .flags = GENL_UNS_ADMIN_PERM,
691 .doit = ethnl_set_debug,
694 .cmd = ETHTOOL_MSG_WOL_GET,
695 .flags = GENL_UNS_ADMIN_PERM,
696 .doit = ethnl_default_doit,
697 .start = ethnl_default_start,
698 .dumpit = ethnl_default_dumpit,
699 .done = ethnl_default_done,
702 .cmd = ETHTOOL_MSG_WOL_SET,
703 .flags = GENL_UNS_ADMIN_PERM,
704 .doit = ethnl_set_wol,
708 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
709 [ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
712 static struct genl_family ethtool_genl_family = {
713 .name = ETHTOOL_GENL_NAME,
714 .version = ETHTOOL_GENL_VERSION,
716 .parallel_ops = true,
717 .ops = ethtool_genl_ops,
718 .n_ops = ARRAY_SIZE(ethtool_genl_ops),
719 .mcgrps = ethtool_nl_mcgrps,
720 .n_mcgrps = ARRAY_SIZE(ethtool_nl_mcgrps),
725 static int __init ethnl_init(void)
729 ret = genl_register_family(ðtool_genl_family);
730 if (WARN(ret < 0, "ethtool: genetlink family registration failed"))
737 subsys_initcall(ethnl_init);