[thirdparty/systemd.git] / src / network / networkd-setlink.c

/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <netinet/in.h>
#include <linux/if.h>

#include "missing_network.h"
#include "netlink-util.h"
#include "networkd-link.h"
#include "networkd-manager.h"
#include "networkd-queue.h"
#include "string-table.h"

static const char *const set_link_operation_table[_SET_LINK_OPERATION_MAX] = {
        [SET_LINK_FLAGS]                   = "link flags",
        [SET_LINK_MTU]                     = "MTU",
};

DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(set_link_operation, SetLinkOperation);

static int set_link_handler_internal(sd_netlink *rtnl, sd_netlink_message *m, Link *link, SetLinkOperation op, bool ignore) {
        int r;

        assert(m);
        assert(link);
        assert(link->set_link_messages > 0);
        assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);

        link->set_link_messages--;

        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                return 0;

        r = sd_netlink_message_get_errno(m);
        if (r < 0) {
                const char *error_msg;

                error_msg = strjoina("Failed to set ", set_link_operation_to_string(op), ignore ? ", ignoring" : "");
                log_link_message_warning_errno(link, m, r, error_msg);

                if (!ignore)
                        link_enter_failed(link);
                return 0;
        }

        log_link_debug(link, "%s set.", set_link_operation_to_string(op));
        return 1;
}

static int link_set_flags_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
        return set_link_handler_internal(rtnl, m, link, SET_LINK_FLAGS, true);
}

static int link_set_mtu_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
        int r;

        r = set_link_handler_internal(rtnl, m, link, SET_LINK_MTU, true);
        if (r <= 0)
                return r;

        /* The kernel resets ipv6 mtu after changing device mtu;
         * we must set this here, after we've set device mtu */
        r = link_set_ipv6_mtu(link);
        if (r < 0)
                log_link_warning_errno(link, r, "Failed to set IPv6 MTU, ignoring: %m");

        if (link->entering_to_join_netdev) {
                r = link_enter_join_netdev(link);
                if (r < 0)
                        link_enter_failed(link);
        }

        return 0;
}

static int link_configure(
                Link *link,
                SetLinkOperation op,
                void *userdata,
                link_netlink_message_handler_t callback) {

        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
        int r;

        assert(link);
        assert(link->manager);
        assert(link->manager->rtnl);
        assert(link->network);
        assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);
        assert(callback);

        log_link_debug(link, "Setting %s", set_link_operation_to_string(op));

        r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
        if (r < 0)
                return log_link_debug_errno(link, r, "Could not allocate RTM_SETLINK message: %m");

        switch (op) {
        case SET_LINK_FLAGS: {
                unsigned ifi_change = 0, ifi_flags = 0;

                if (link->network->arp >= 0) {
                        ifi_change |= IFF_NOARP;
                        SET_FLAG(ifi_flags, IFF_NOARP, link->network->arp == 0);
                }

                if (link->network->multicast >= 0) {
                        ifi_change |= IFF_MULTICAST;
                        SET_FLAG(ifi_flags, IFF_MULTICAST, link->network->multicast);
                }

                if (link->network->allmulticast >= 0) {
                        ifi_change |= IFF_ALLMULTI;
                        SET_FLAG(ifi_flags, IFF_ALLMULTI, link->network->allmulticast);
                }

                if (link->network->promiscuous >= 0) {
                        ifi_change |= IFF_PROMISC;
                        SET_FLAG(ifi_flags, IFF_PROMISC, link->network->promiscuous);
                }

                r = sd_rtnl_message_link_set_flags(req, ifi_flags, ifi_change);
                if (r < 0)
                        return log_link_debug_errno(link, r, "Could not set link flags: %m");

                break;
        }
        case SET_LINK_MTU:
                r = sd_netlink_message_append_u32(req, IFLA_MTU, PTR_TO_UINT32(userdata));
                if (r < 0)
                        return log_link_debug_errno(link, r, "Could not append IFLA_MTU attribute: %m");
                break;
        default:
                assert_not_reached("Invalid set link operation");
        }

        r = netlink_call_async(link->manager->rtnl, NULL, req, callback,
                               link_netlink_destroy_callback, link);
        if (r < 0)
                return log_link_debug_errno(link, r, "Could not send RTM_SETLINK message: %m");

        link_ref(link);
        return 0;
}

static bool link_is_ready_to_call_set_link(Request *req) {
        Link *link;

        assert(req);

        link = req->link;

        if (!IN_SET(link->state, LINK_STATE_INITIALIZED, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
                return false;

        return true;
}

int request_process_set_link(Request *req) {
        int r;

        assert(req);
        assert(req->link);
        assert(req->type == REQUEST_TYPE_SET_LINK);
        assert(req->set_link_operation >= 0 && req->set_link_operation < _SET_LINK_OPERATION_MAX);
        assert(req->netlink_handler);

        if (!link_is_ready_to_call_set_link(req))
                return 0;

        r = link_configure(req->link, req->set_link_operation, req->userdata, req->netlink_handler);
        if (r < 0)
                return log_link_error_errno(req->link, r, "Failed to set %s: %m",
                                            set_link_operation_to_string(req->set_link_operation));

        return 1;
}

static int link_request_set_link(
                Link *link,
                SetLinkOperation op,
                link_netlink_message_handler_t netlink_handler,
                Request **ret) {

        Request *req;
        int r;

        assert(link);
        assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);
        assert(netlink_handler);

        r = link_queue_request(link, REQUEST_TYPE_SET_LINK, INT_TO_PTR(op), false,
                               &link->set_link_messages, netlink_handler, &req);
        if (r < 0)
                return log_link_error_errno(link, r, "Failed to request to set %s: %m",
                                            set_link_operation_to_string(op));

        log_link_debug(link, "Requested to set %s", set_link_operation_to_string(op));

        if (ret)
                *ret = req;
        return 0;
}

int link_request_to_set_flags(Link *link) {
        assert(link);
        assert(link->network);

        if (link->network->arp < 0 &&
            link->network->multicast < 0 &&
            link->network->allmulticast < 0 &&
            link->network->promiscuous < 0)
                return 0;

        return link_request_set_link(link, SET_LINK_FLAGS, link_set_flags_handler, NULL);
}

int link_request_to_set_mtu(Link *link, uint32_t mtu) {
        Request *req = NULL;  /* avoid false maybe-uninitialized warning */
        int r;

        assert(link);

        /* IPv6 protocol requires a minimum MTU of IPV6_MTU_MIN(1280) bytes on the interface. Bump up
         * MTU bytes to IPV6_MTU_MIN. */
        if (mtu < IPV6_MIN_MTU && link_ipv6_enabled(link)) {
                log_link_warning(link, "Bumping MTU to " STRINGIFY(IPV6_MIN_MTU) ", as IPv6 is enabled "
                                 "and requires a minimum MTU of " STRINGIFY(IPV6_MIN_MTU) " bytes");
                mtu = IPV6_MIN_MTU;
        }

        if (link->mtu == mtu)
                return 0;

        r = link_request_set_link(link, SET_LINK_MTU, link_set_mtu_handler, &req);
        if (r < 0)
                return r;

        req->userdata = UINT32_TO_PTR(mtu);
        return 0;
}

static bool link_reduces_vlan_mtu(Link *link) {
        /* See netif_reduces_vlan_mtu() in kernel. */
        return streq_ptr(link->kind, "macsec");
}

static uint32_t link_get_requested_mtu_by_stacked_netdevs(Link *link) {
        uint32_t mtu = 0;
        NetDev *dev;

        HASHMAP_FOREACH(dev, link->network->stacked_netdevs)
                if (dev->kind == NETDEV_KIND_VLAN && dev->mtu > 0)
                        /* See vlan_dev_change_mtu() in kernel. */
                        mtu = MAX(mtu, link_reduces_vlan_mtu(link) ? dev->mtu + 4 : dev->mtu);

                else if (dev->kind == NETDEV_KIND_MACVLAN && dev->mtu > mtu)
                        /* See macvlan_change_mtu() in kernel. */
                        mtu = dev->mtu;

        return mtu;
}

int link_configure_mtu(Link *link) {
        uint32_t mtu;

        assert(link);
        assert(link->network);

        if (link->network->mtu > 0)
                return link_request_to_set_mtu(link, link->network->mtu);

        mtu = link_get_requested_mtu_by_stacked_netdevs(link);
        if (link->mtu >= mtu)
                return 0;

        log_link_notice(link, "Bumping MTU bytes from %"PRIu32" to %"PRIu32" because of stacked device. "
                        "If it is not desired, then please explicitly specify MTUBytes= setting.",
                        link->mtu, mtu);

        return link_request_to_set_mtu(link, mtu);
}
Commit	Line	Data
0fa8ee6c YW	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
0fa8ee6c YW	2
93fabc10 YW	3	#include <netinet/in.h>
	4	#include <linux/if.h>
	5
0fa8ee6c YW	6	#include "missing_network.h"
	7	#include "netlink-util.h"
	8	#include "networkd-link.h"
	9	#include "networkd-manager.h"
	10	#include "networkd-queue.h"
	11	#include "string-table.h"
	12
	13	static const char *const set_link_operation_table[_SET_LINK_OPERATION_MAX] = {
93fabc10	14	[SET_LINK_FLAGS] = "link flags",
0fa8ee6c YW	15	[SET_LINK_MTU] = "MTU",
	16	};
	17
	18	DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(set_link_operation, SetLinkOperation);
	19
	20	static int set_link_handler_internal(sd_netlink rtnl, sd_netlink_message m, Link *link, SetLinkOperation op, bool ignore) {
	21	int r;
	22
	23	assert(m);
	24	assert(link);
	25	assert(link->set_link_messages > 0);
	26	assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);
	27
	28	link->set_link_messages--;
	29
	30	if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
	31	return 0;
	32
	33	r = sd_netlink_message_get_errno(m);
	34	if (r < 0) {
	35	const char *error_msg;
	36
	37	error_msg = strjoina("Failed to set ", set_link_operation_to_string(op), ignore ? ", ignoring" : "");
	38	log_link_message_warning_errno(link, m, r, error_msg);
	39
	40	if (!ignore)
	41	link_enter_failed(link);
	42	return 0;
	43	}
	44
	45	log_link_debug(link, "%s set.", set_link_operation_to_string(op));
	46	return 1;
	47	}
	48
93fabc10 YW	49	static int link_set_flags_handler(sd_netlink rtnl, sd_netlink_message m, Link *link) {
	50	return set_link_handler_internal(rtnl, m, link, SET_LINK_FLAGS, true);
	51	}
	52
0fa8ee6c YW	53	static int link_set_mtu_handler(sd_netlink rtnl, sd_netlink_message m, Link *link) {
	54	int r;
	55
	56	r = set_link_handler_internal(rtnl, m, link, SET_LINK_MTU, true);
	57	if (r <= 0)
	58	return r;
	59
	60	/* The kernel resets ipv6 mtu after changing device mtu;
	61	* we must set this here, after we've set device mtu */
	62	r = link_set_ipv6_mtu(link);
	63	if (r < 0)
	64	log_link_warning_errno(link, r, "Failed to set IPv6 MTU, ignoring: %m");
	65
	66	if (link->entering_to_join_netdev) {
	67	r = link_enter_join_netdev(link);
	68	if (r < 0)
	69	link_enter_failed(link);
	70	}
	71
	72	return 0;
	73	}
	74
	75	static int link_configure(
	76	Link *link,
	77	SetLinkOperation op,
	78	void *userdata,
	79	link_netlink_message_handler_t callback) {
	80
	81	_cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL;
	82	int r;
	83
	84	assert(link);
	85	assert(link->manager);
	86	assert(link->manager->rtnl);
	87	assert(link->network);
	88	assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);
	89	assert(callback);
	90
	91	log_link_debug(link, "Setting %s", set_link_operation_to_string(op));
	92
	93	r = sd_rtnl_message_new_link(link->manager->rtnl, &req, RTM_SETLINK, link->ifindex);
	94	if (r < 0)
	95	return log_link_debug_errno(link, r, "Could not allocate RTM_SETLINK message: %m");
	96
	97	switch (op) {
93fabc10 YW	98	case SET_LINK_FLAGS: {
	99	unsigned ifi_change = 0, ifi_flags = 0;
	100
	101	if (link->network->arp >= 0) {
	102	ifi_change \|= IFF_NOARP;
	103	SET_FLAG(ifi_flags, IFF_NOARP, link->network->arp == 0);
	104	}
	105
	106	if (link->network->multicast >= 0) {
	107	ifi_change \|= IFF_MULTICAST;
	108	SET_FLAG(ifi_flags, IFF_MULTICAST, link->network->multicast);
	109	}
	110
	111	if (link->network->allmulticast >= 0) {
	112	ifi_change \|= IFF_ALLMULTI;
	113	SET_FLAG(ifi_flags, IFF_ALLMULTI, link->network->allmulticast);
	114	}
	115
	116	if (link->network->promiscuous >= 0) {
	117	ifi_change \|= IFF_PROMISC;
	118	SET_FLAG(ifi_flags, IFF_PROMISC, link->network->promiscuous);
	119	}
	120
	121	r = sd_rtnl_message_link_set_flags(req, ifi_flags, ifi_change);
	122	if (r < 0)
	123	return log_link_debug_errno(link, r, "Could not set link flags: %m");
	124
	125	break;
	126	}
0fa8ee6c YW	127	case SET_LINK_MTU:
	128	r = sd_netlink_message_append_u32(req, IFLA_MTU, PTR_TO_UINT32(userdata));
	129	if (r < 0)
	130	return log_link_debug_errno(link, r, "Could not append IFLA_MTU attribute: %m");
	131	break;
	132	default:
	133	assert_not_reached("Invalid set link operation");
	134	}
	135
	136	r = netlink_call_async(link->manager->rtnl, NULL, req, callback,
	137	link_netlink_destroy_callback, link);
	138	if (r < 0)
	139	return log_link_debug_errno(link, r, "Could not send RTM_SETLINK message: %m");
	140
	141	link_ref(link);
	142	return 0;
	143	}
	144
	145	static bool link_is_ready_to_call_set_link(Request *req) {
	146	Link *link;
	147
	148	assert(req);
	149
	150	link = req->link;
	151
	152	if (!IN_SET(link->state, LINK_STATE_INITIALIZED, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
	153	return false;
	154
	155	return true;
	156	}
	157
	158	int request_process_set_link(Request *req) {
	159	int r;
	160
	161	assert(req);
	162	assert(req->link);
	163	assert(req->type == REQUEST_TYPE_SET_LINK);
	164	assert(req->set_link_operation >= 0 && req->set_link_operation < _SET_LINK_OPERATION_MAX);
	165	assert(req->netlink_handler);
	166
	167	if (!link_is_ready_to_call_set_link(req))
	168	return 0;
	169
	170	r = link_configure(req->link, req->set_link_operation, req->userdata, req->netlink_handler);
	171	if (r < 0)
	172	return log_link_error_errno(req->link, r, "Failed to set %s: %m",
	173	set_link_operation_to_string(req->set_link_operation));
	174
	175	return 1;
	176	}
	177
	178	static int link_request_set_link(
	179	Link *link,
	180	SetLinkOperation op,
	181	link_netlink_message_handler_t netlink_handler,
	182	Request **ret) {
	183
	184	Request *req;
	185	int r;
	186
	187	assert(link);
	188	assert(op >= 0 && op < _SET_LINK_OPERATION_MAX);
	189	assert(netlink_handler);
	190
191	r = link_queue_request(link, REQUEST_TYPE_SET_LINK, INT_TO_PTR(op), false,
192	&link->set_link_messages, netlink_handler, &req);
193	if (r < 0)
194	return log_link_error_errno(link, r, "Failed to request to set %s: %m",
195	set_link_operation_to_string(op));
196
197	log_link_debug(link, "Requested to set %s", set_link_operation_to_string(op));
198
199	if (ret)
200	*ret = req;
201	return 0;
202	}
203
93fabc10 YW	204	int link_request_to_set_flags(Link *link) {
	205	assert(link);
	206	assert(link->network);
	207
	208	if (link->network->arp < 0 &&
	209	link->network->multicast < 0 &&
	210	link->network->allmulticast < 0 &&
	211	link->network->promiscuous < 0)
	212	return 0;
	213
	214	return link_request_set_link(link, SET_LINK_FLAGS, link_set_flags_handler, NULL);
	215	}
	216
0fa8ee6c YW	217	int link_request_to_set_mtu(Link *link, uint32_t mtu) {
	218	Request req = NULL; / avoid false maybe-uninitialized warning */
	219	int r;
	220
	221	assert(link);
	222
	223	/* IPv6 protocol requires a minimum MTU of IPV6_MTU_MIN(1280) bytes on the interface. Bump up
	224	* MTU bytes to IPV6_MTU_MIN. */
	225	if (mtu < IPV6_MIN_MTU && link_ipv6_enabled(link)) {
	226	log_link_warning(link, "Bumping MTU to " STRINGIFY(IPV6_MIN_MTU) ", as IPv6 is enabled "
	227	"and requires a minimum MTU of " STRINGIFY(IPV6_MIN_MTU) " bytes");
	228	mtu = IPV6_MIN_MTU;
	229	}
	230
	231	if (link->mtu == mtu)
	232	return 0;
	233
	234	r = link_request_set_link(link, SET_LINK_MTU, link_set_mtu_handler, &req);
	235	if (r < 0)
	236	return r;
	237
	238	req->userdata = UINT32_TO_PTR(mtu);
	239	return 0;
	240	}
	241
	242	static bool link_reduces_vlan_mtu(Link *link) {
	243	/* See netif_reduces_vlan_mtu() in kernel. */
	244	return streq_ptr(link->kind, "macsec");
	245	}
	246
	247	static uint32_t link_get_requested_mtu_by_stacked_netdevs(Link *link) {
	248	uint32_t mtu = 0;
	249	NetDev *dev;
	250
	251	HASHMAP_FOREACH(dev, link->network->stacked_netdevs)
	252	if (dev->kind == NETDEV_KIND_VLAN && dev->mtu > 0)
	253	/* See vlan_dev_change_mtu() in kernel. */
	254	mtu = MAX(mtu, link_reduces_vlan_mtu(link) ? dev->mtu + 4 : dev->mtu);
	255
	256	else if (dev->kind == NETDEV_KIND_MACVLAN && dev->mtu > mtu)
	257	/* See macvlan_change_mtu() in kernel. */
	258	mtu = dev->mtu;
	259
	260	return mtu;
	261	}
	262
	263	int link_configure_mtu(Link *link) {
	264	uint32_t mtu;
	265
	266	assert(link);
	267	assert(link->network);
	268
	269	if (link->network->mtu > 0)
	270	return link_request_to_set_mtu(link, link->network->mtu);
	271
	272	mtu = link_get_requested_mtu_by_stacked_netdevs(link);
	273	if (link->mtu >= mtu)
	274	return 0;
	275
	276	log_link_notice(link, "Bumping MTU bytes from %"PRIu32" to %"PRIu32" because of stacked device. "
	277	"If it is not desired, then please explicitly specify MTUBytes= setting.",
	278	link->mtu, mtu);
	279
	280	return link_request_to_set_mtu(link, mtu);
281	}