1 // SPDX-License-Identifier: GPL-2.0-or-later
7  *  This file contains the implementation of an IRQ-safe, crash-safe
13  * 2001-09-17    started by Ingo Molnar.
14  * 2003-08-11    2.6 port by Matt Mackall
17  *               works non-modular
18  * 2003-09-07    rewritten with netpoll api
29 #include <linux/module.h>
49 MODULE_PARM_DESC(netconsole, " netconsole=[src-port]@[src-ip]/[dev],[tgt-port]@<tgt-ip>/[tgt-macadd…
55 #ifndef	MODULE
62 #endif	/* MODULE */
77  * struct netconsole_target - Represents a configured netconsole target.
78  * @list:	Links this target into the target_list.
80  * @enabled:	On / off knob to enable / disable target.
81  *		Visible from userspace (read-write).
84  *		Also, other parameters of a target may be modified at
86  * @np:		The netpoll structure for this target.
88  *		dev_name	(read-write)
89  *		local_port	(read-write)
90  *		remote_port	(read-write)
91  *		local_ip	(read-write)
92  *		remote_ip	(read-write)
93  *		local_mac	(read-only)
94  *		remote_mac	(read-write)
124  * Targets that were created by parsing the boot/module option string
126  * never go away, so make these a no-op for them.
130 	if (config_item_name(&nt->item))  in netconsole_target_get()
131 		config_item_get(&nt->item);  in netconsole_target_get()
136 	if (config_item_name(&nt->item))  in netconsole_target_put()
137 		config_item_put(&nt->item);  in netconsole_target_put()
165 /* Allocate new target (from boot/module param) and setup netpoll for it */
168 	int err = -ENOMEM;  in alloc_param_target()
173 	 * Note that these targets get their config_item fields zeroed-out.  in alloc_param_target()
179 	nt->np.name = "netconsole";  in alloc_param_target()
180 	strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);  in alloc_param_target()
181 	nt->np.local_port = 6665;  in alloc_param_target()
182 	nt->np.remote_port = 6666;  in alloc_param_target()
183 	eth_broadcast_addr(nt->np.remote_mac);  in alloc_param_target()
186 		nt->extended = true;  in alloc_param_target()
191 	err = netpoll_parse_options(&nt->np, target_config);  in alloc_param_target()
195 	err = netpoll_setup(&nt->np);  in alloc_param_target()
199 	nt->enabled = true;  in alloc_param_target()
208 /* Cleanup netpoll for given target (from boot/module param) and free it */
211 	netpoll_cleanup(&nt->np);  in free_param_target()
222  *				<target>/
232  *				<target>/...
248 	return snprintf(buf, PAGE_SIZE, "%d\n", to_target(item)->enabled);  in enabled_show()
253 	return snprintf(buf, PAGE_SIZE, "%d\n", to_target(item)->extended);  in extended_show()
258 	return snprintf(buf, PAGE_SIZE, "%s\n", to_target(item)->np.dev_name);  in dev_name_show()
263 	return snprintf(buf, PAGE_SIZE, "%d\n", to_target(item)->np.local_port);  in local_port_show()
268 	return snprintf(buf, PAGE_SIZE, "%d\n", to_target(item)->np.remote_port);  in remote_port_show()
275 	if (nt->np.ipv6)  in local_ip_show()
276 		return snprintf(buf, PAGE_SIZE, "%pI6c\n", &nt->np.local_ip.in6);  in local_ip_show()
278 		return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.local_ip);  in local_ip_show()
285 	if (nt->np.ipv6)  in remote_ip_show()
286 		return snprintf(buf, PAGE_SIZE, "%pI6c\n", &nt->np.remote_ip.in6);  in remote_ip_show()
288 		return snprintf(buf, PAGE_SIZE, "%pI4\n", &nt->np.remote_ip);  in remote_ip_show()
293 	struct net_device *dev = to_target(item)->np.dev;  in local_mac_show()
296 	return snprintf(buf, PAGE_SIZE, "%pM\n", dev ? dev->dev_addr : bcast);  in local_mac_show()
301 	return snprintf(buf, PAGE_SIZE, "%pM\n", to_target(item)->np.remote_mac);  in remote_mac_show()
305  * This one is special -- targets created through the configfs interface
324 	err = -EINVAL;  in enabled_store()
327 	if ((bool)enabled == nt->enabled) {  in enabled_store()
329 			nt->enabled ? "started" : "stopped");  in enabled_store()
334 		if (nt->extended && !(netconsole_ext.flags & CON_ENABLED)) {  in enabled_store()
340 		 * Skip netpoll_parse_options() -- all the attributes are  in enabled_store()
343 		netpoll_print_options(&nt->np);  in enabled_store()
345 		err = netpoll_setup(&nt->np);  in enabled_store()
353 		 * nt->np.dev == NULL and nt->enabled == true  in enabled_store()
356 		nt->enabled = false;  in enabled_store()
358 		netpoll_cleanup(&nt->np);  in enabled_store()
361 	nt->enabled = enabled;  in enabled_store()
378 	if (nt->enabled) {  in extended_store()
379 		pr_err("target (%s) is enabled, disable to update parameters\n",  in extended_store()
380 		       config_item_name(&nt->item));  in extended_store()
381 		err = -EINVAL;  in extended_store()
389 		err = -EINVAL;  in extended_store()
393 	nt->extended = extended;  in extended_store()
409 	if (nt->enabled) {  in dev_name_store()
410 		pr_err("target (%s) is enabled, disable to update parameters\n",  in dev_name_store()
411 		       config_item_name(&nt->item));  in dev_name_store()
413 		return -EINVAL;  in dev_name_store()
416 	strlcpy(nt->np.dev_name, buf, IFNAMSIZ);  in dev_name_store()
419 	len = strnlen(nt->np.dev_name, IFNAMSIZ);  in dev_name_store()
420 	if (nt->np.dev_name[len - 1] == '\n')  in dev_name_store()
421 		nt->np.dev_name[len - 1] = '\0';  in dev_name_store()
431 	int rv = -EINVAL;  in local_port_store()
434 	if (nt->enabled) {  in local_port_store()
435 		pr_err("target (%s) is enabled, disable to update parameters\n",  in local_port_store()
436 		       config_item_name(&nt->item));  in local_port_store()
440 	rv = kstrtou16(buf, 10, &nt->np.local_port);  in local_port_store()
454 	int rv = -EINVAL;  in remote_port_store()
457 	if (nt->enabled) {  in remote_port_store()
458 		pr_err("target (%s) is enabled, disable to update parameters\n",  in remote_port_store()
459 		       config_item_name(&nt->item));  in remote_port_store()
463 	rv = kstrtou16(buf, 10, &nt->np.remote_port);  in remote_port_store()
479 	if (nt->enabled) {  in local_ip_store()
480 		pr_err("target (%s) is enabled, disable to update parameters\n",  in local_ip_store()
481 		       config_item_name(&nt->item));  in local_ip_store()
487 		if (in6_pton(buf, count, nt->np.local_ip.in6.s6_addr, -1, &end) > 0) {  in local_ip_store()
492 			nt->np.ipv6 = true;  in local_ip_store()
496 		if (!nt->np.ipv6) {  in local_ip_store()
497 			nt->np.local_ip.ip = in_aton(buf);  in local_ip_store()
506 	return -EINVAL;  in local_ip_store()
515 	if (nt->enabled) {  in remote_ip_store()
516 		pr_err("target (%s) is enabled, disable to update parameters\n",  in remote_ip_store()
517 		       config_item_name(&nt->item));  in remote_ip_store()
523 		if (in6_pton(buf, count, nt->np.remote_ip.in6.s6_addr, -1, &end) > 0) {  in remote_ip_store()
528 			nt->np.ipv6 = true;  in remote_ip_store()
532 		if (!nt->np.ipv6) {  in remote_ip_store()
533 			nt->np.remote_ip.ip = in_aton(buf);  in remote_ip_store()
542 	return -EINVAL;  in remote_ip_store()
552 	if (nt->enabled) {  in remote_mac_store()
553 		pr_err("target (%s) is enabled, disable to update parameters\n",  in remote_mac_store()
554 		       config_item_name(&nt->item));  in remote_mac_store()
560 	if (buf[3 * ETH_ALEN - 1] && buf[3 * ETH_ALEN - 1] != '\n')  in remote_mac_store()
562 	memcpy(nt->np.remote_mac, remote_mac, ETH_ALEN);  in remote_mac_store()
568 	return -EINVAL;  in remote_mac_store()
625 	 * Target is disabled at creation (!enabled).  in make_netconsole_target()
629 		return ERR_PTR(-ENOMEM);  in make_netconsole_target()
631 	nt->np.name = "netconsole";  in make_netconsole_target()
632 	strlcpy(nt->np.dev_name, "eth0", IFNAMSIZ);  in make_netconsole_target()
633 	nt->np.local_port = 6665;  in make_netconsole_target()
634 	nt->np.remote_port = 6666;  in make_netconsole_target()
635 	eth_broadcast_addr(nt->np.remote_mac);  in make_netconsole_target()
638 	config_item_init_type_name(&nt->item, name, &netconsole_target_type);  in make_netconsole_target()
642 	list_add(&nt->list, &target_list);  in make_netconsole_target()
645 	return &nt->item;  in make_netconsole_target()
655 	list_del(&nt->list);  in drop_netconsole_target()
659 	 * The target may have never been enabled, or was manually disabled  in drop_netconsole_target()
662 	if (nt->enabled)  in drop_netconsole_target()
663 		netpoll_cleanup(&nt->np);  in drop_netconsole_target()
665 	config_item_put(&nt->item);  in drop_netconsole_target()
707 		if (nt->np.dev == dev) {  in netconsole_netdev_event()
710 				strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);  in netconsole_netdev_event()
720 				__netpoll_cleanup(&nt->np);  in netconsole_netdev_event()
723 				dev_put(nt->np.dev);  in netconsole_netdev_event()
724 				nt->np.dev = NULL;  in netconsole_netdev_event()
725 				nt->enabled = false;  in netconsole_netdev_event()
748 			dev->name, msg);  in netconsole_netdev_event()
760  * send_ext_msg_udp - send extended log message to target
761  * @nt: target to send message to
778 		netpoll_send_udp(&nt->np, msg, msg_len);  in send_ext_msg_udp()
788 	header_len = body - header;  in send_ext_msg_udp()
789 	body_len = msg_len - header_len - 1;  in send_ext_msg_udp()
794 	 * "ncfrag=<byte-offset>/<total-bytes>"  in send_ext_msg_udp()
803 					 sizeof(buf) - this_header,  in send_ext_msg_udp()
806 		this_chunk = min(body_len - offset,  in send_ext_msg_udp()
807 				 MAX_PRINT_CHUNK - this_header);  in send_ext_msg_udp()
813 		netpoll_send_udp(&nt->np, buf, this_header + this_chunk);  in send_ext_msg_udp()
830 		if (nt->extended && nt->enabled && netif_running(nt->np.dev))  in write_ext_msg()
850 		if (!nt->extended && nt->enabled && netif_running(nt->np.dev)) {  in write_msg()
852 			 * We nest this inside the for-each-target loop above  in write_msg()
854 			 * at least one target if we die inside here, instead  in write_msg()
855 			 * of unnecessarily keeping all targets in lock-step.  in write_msg()
860 				netpoll_send_udp(&nt->np, tmp, frag);  in write_msg()
862 				left -= frag;  in write_msg()
897 			if (nt->extended)  in init_netconsole()
904 			list_add(&nt->list, &target_list);  in init_netconsole()
932 	 * from the boot/module option exist here). Skipping the list  in init_netconsole()
936 		list_del(&nt->list);  in init_netconsole()
953 	 * Targets created via configfs pin references on our module  in cleanup_netconsole()
956 	 * created from the boot/module option are left, so remove and  in cleanup_netconsole()
961 		list_del(&nt->list);  in cleanup_netconsole()
968  * initialized after network device driver if built-in.
970  * late_initcall() and module_init() are identical if built as module.