[thirdparty/systemd.git] / src / shared / local-addresses.c

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

#include "sd-netlink.h"

#include "alloc-util.h"
#include "local-addresses.h"
#include "macro.h"
#include "netlink-util.h"
#include "sort-util.h"

static int address_compare(const struct local_address *a, const struct local_address *b) {
        int r;

        /* Order lowest scope first, IPv4 before IPv6, lowest interface index first */

        if (a->family == AF_INET && b->family == AF_INET6)
                return -1;
        if (a->family == AF_INET6 && b->family == AF_INET)
                return 1;

        r = CMP(a->scope, b->scope);
        if (r != 0)
                return r;

        r = CMP(a->metric, b->metric);
        if (r != 0)
                return r;

        r = CMP(a->ifindex, b->ifindex);
        if (r != 0)
                return r;

        return memcmp(&a->address, &b->address, FAMILY_ADDRESS_SIZE(a->family));
}

int local_addresses(sd_netlink *context, int ifindex, int af, struct local_address **ret) {
        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
        _cleanup_free_ struct local_address *list = NULL;
        size_t n_list = 0, n_allocated = 0;
        sd_netlink_message *m;
        int r;

        if (context)
                rtnl = sd_netlink_ref(context);
        else {
                r = sd_netlink_open(&rtnl);
                if (r < 0)
                        return r;
        }

        r = sd_rtnl_message_new_addr(rtnl, &req, RTM_GETADDR, 0, af);
        if (r < 0)
                return r;

        r = sd_netlink_call(rtnl, req, 0, &reply);
        if (r < 0)
                return r;

        for (m = reply; m; m = sd_netlink_message_next(m)) {
                struct local_address *a;
                unsigned char flags;
                uint16_t type;
                int ifi, family;

                r = sd_netlink_message_get_errno(m);
                if (r < 0)
                        return r;

                r = sd_netlink_message_get_type(m, &type);
                if (r < 0)
                        return r;
                if (type != RTM_NEWADDR)
                        continue;

                r = sd_rtnl_message_addr_get_ifindex(m, &ifi);
                if (r < 0)
                        return r;
                if (ifindex > 0 && ifi != ifindex)
                        continue;

                r = sd_rtnl_message_addr_get_family(m, &family);
                if (r < 0)
                        return r;
                if (af != AF_UNSPEC && af != family)
                        continue;

                r = sd_rtnl_message_addr_get_flags(m, &flags);
                if (r < 0)
                        return r;
                if (flags & IFA_F_DEPRECATED)
                        continue;

                if (!GREEDY_REALLOC0(list, n_allocated, n_list+1))
                        return -ENOMEM;

                a = list + n_list;

                r = sd_rtnl_message_addr_get_scope(m, &a->scope);
                if (r < 0)
                        return r;

                if (ifindex == 0 && IN_SET(a->scope, RT_SCOPE_HOST, RT_SCOPE_NOWHERE))
                        continue;

                switch (family) {

                case AF_INET:
                        r = sd_netlink_message_read_in_addr(m, IFA_LOCAL, &a->address.in);
                        if (r < 0) {
                                r = sd_netlink_message_read_in_addr(m, IFA_ADDRESS, &a->address.in);
                                if (r < 0)
                                        continue;
                        }
                        break;

                case AF_INET6:
                        r = sd_netlink_message_read_in6_addr(m, IFA_LOCAL, &a->address.in6);
                        if (r < 0) {
                                r = sd_netlink_message_read_in6_addr(m, IFA_ADDRESS, &a->address.in6);
                                if (r < 0)
                                        continue;
                        }
                        break;

                default:
                        continue;
                }

                a->ifindex = ifi;
                a->family = family;

                n_list++;
        };

        if (ret) {
                typesafe_qsort(list, n_list, address_compare);
                *ret = TAKE_PTR(list);
        }

        return (int) n_list;
}

static int add_local_gateway(
                struct local_address **list,
                size_t *n_list,
                size_t *n_allocated,
                int af,
                int ifindex,
                uint32_t metric,
                const RouteVia *via) {

        assert(list);
        assert(n_list);
        assert(n_allocated);
        assert(via);

        if (af != AF_UNSPEC && af != via->family)
                return 0;

        if (!GREEDY_REALLOC(*list, *n_allocated, *n_list + 1))
                return -ENOMEM;

        (*list)[(*n_list)++] = (struct local_address) {
                .ifindex = ifindex,
                .metric = metric,
                .family = via->family,
                .address = via->address,
        };

        return 0;
}

int local_gateways(sd_netlink *context, int ifindex, int af, struct local_address **ret) {
        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
        _cleanup_free_ struct local_address *list = NULL;
        size_t n_list = 0, n_allocated = 0;
        int r;

        if (context)
                rtnl = sd_netlink_ref(context);
        else {
                r = sd_netlink_open(&rtnl);
                if (r < 0)
                        return r;
        }

        r = sd_rtnl_message_new_route(rtnl, &req, RTM_GETROUTE, af, RTPROT_UNSPEC);
        if (r < 0)
                return r;

        r = sd_netlink_message_request_dump(req, true);
        if (r < 0)
                return r;

        r = sd_netlink_call(rtnl, req, 0, &reply);
        if (r < 0)
                return r;

        for (sd_netlink_message *m = reply; m; m = sd_netlink_message_next(m)) {
                _cleanup_ordered_set_free_free_ OrderedSet *multipath_routes = NULL;
                _cleanup_free_ void *rta_multipath = NULL;
                union in_addr_union gateway;
                uint16_t type;
                unsigned char dst_len, src_len, table;
                uint32_t ifi = 0, metric = 0;
                size_t rta_len;
                int family;
                RouteVia via;

                r = sd_netlink_message_get_errno(m);
                if (r < 0)
                        return r;

                r = sd_netlink_message_get_type(m, &type);
                if (r < 0)
                        return r;
                if (type != RTM_NEWROUTE)
                        continue;

                /* We only care for default routes */
                r = sd_rtnl_message_route_get_dst_prefixlen(m, &dst_len);
                if (r < 0)
                        return r;
                if (dst_len != 0)
                        continue;

                r = sd_rtnl_message_route_get_src_prefixlen(m, &src_len);
                if (r < 0)
                        return r;
                if (src_len != 0)
                        continue;

                r = sd_rtnl_message_route_get_table(m, &table);
                if (r < 0)
                        return r;
                if (table != RT_TABLE_MAIN)
                        continue;

                r = sd_netlink_message_read_u32(m, RTA_PRIORITY, &metric);
                if (r < 0 && r != -ENODATA)
                        return r;

                r = sd_rtnl_message_route_get_family(m, &family);
                if (r < 0)
                        return r;
                if (!IN_SET(family, AF_INET, AF_INET6))
                        continue;

                r = sd_netlink_message_read_u32(m, RTA_OIF, &ifi);
                if (r < 0 && r != -ENODATA)
                        return r;
                if (r >= 0) {
                        if (ifi <= 0)
                                return -EINVAL;
                        if (ifindex > 0 && (int) ifi != ifindex)
                                continue;

                        r = netlink_message_read_in_addr_union(m, RTA_GATEWAY, family, &gateway);
                        if (r < 0 && r != -ENODATA)
                                return r;
                        if (r >= 0) {
                                via.family = family;
                                via.address = gateway;
                                r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &via);
                                if (r < 0)
                                        return r;

                                continue;
                        }

                        if (family != AF_INET)
                                continue;

                        r = sd_netlink_message_read(m, RTA_VIA, sizeof(via), &via);
                        if (r < 0 && r != -ENODATA)
                                return r;
                        if (r >= 0) {
                                r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &via);
                                if (r < 0)
                                        return r;

                                continue;
                        }
                }

                r = sd_netlink_message_read_data(m, RTA_MULTIPATH, &rta_len, &rta_multipath);
                if (r < 0 && r != -ENODATA)
                        return r;
                if (r >= 0) {
                        MultipathRoute *mr;

                        r = rtattr_read_nexthop(rta_multipath, rta_len, family, &multipath_routes);
                        if (r < 0)
                                return r;

                        ORDERED_SET_FOREACH(mr, multipath_routes) {
                                if (ifindex > 0 && mr->ifindex != ifindex)
                                        continue;

                                r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &mr->gateway);
                                if (r < 0)
                                        return r;
                        }
                }
        }

        if (ret) {
                typesafe_qsort(list, n_list, address_compare);
                *ret = TAKE_PTR(list);
        }

        return (int) n_list;
}
Commit	Line	Data
db9ecf05	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
8041b5ba	2
1c4baffc	3	#include "sd-netlink.h"
b5efdb8a LP	4
b5efdb8a LP	5	#include "alloc-util.h"
e80af1bd	6	#include "local-addresses.h"
cf0fbc49 TA	7	#include "macro.h"
cf0fbc49 TA	8	#include "netlink-util.h"
760877e9	9	#include "sort-util.h"
8041b5ba	10
93bab288 YW	11	static int address_compare(const struct local_address a, const struct local_address b) {
93bab288 YW	12	int r;
5502f0d9 LP	13
	14	/* Order lowest scope first, IPv4 before IPv6, lowest interface index first */
	15
e9140aff LP	16	if (a->family == AF_INET && b->family == AF_INET6)
	17	return -1;
	18	if (a->family == AF_INET6 && b->family == AF_INET)
	19	return 1;
	20
93bab288 YW	21	r = CMP(a->scope, b->scope);
	22	if (r != 0)
	23	return r;
5502f0d9	24
93bab288 YW	25	r = CMP(a->metric, b->metric);
	26	if (r != 0)
	27	return r;
5502f0d9	28
93bab288 YW	29	r = CMP(a->ifindex, b->ifindex);
	30	if (r != 0)
	31	return r;
5502f0d9	32
00d75e57	33	return memcmp(&a->address, &b->address, FAMILY_ADDRESS_SIZE(a->family));
5502f0d9 LP	34	}
5502f0d9 LP	35
1c4baffc	36	int local_addresses(sd_netlink context, int ifindex, int af, struct local_address *ret) {
4afd3348 LP	37	_cleanup_(sd_netlink_message_unrefp) sd_netlink_message req = NULL, reply = NULL;
4afd3348 LP	38	_cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
e80af1bd	39	_cleanup_free_ struct local_address *list = NULL;
5502f0d9	40	size_t n_list = 0, n_allocated = 0;
1c4baffc	41	sd_netlink_message *m;
d1ca51b1	42	int r;
d73c3269	43
ee8c4568	44	if (context)
1c4baffc	45	rtnl = sd_netlink_ref(context);
ee8c4568	46	else {
1c4baffc	47	r = sd_netlink_open(&rtnl);
ee8c4568 LP	48	if (r < 0)
	49	return r;
	50	}
8041b5ba	51
1d050e1e	52	r = sd_rtnl_message_new_addr(rtnl, &req, RTM_GETADDR, 0, af);
d1ca51b1 TG	53	if (r < 0)
d1ca51b1 TG	54	return r;
8041b5ba	55
1c4baffc	56	r = sd_netlink_call(rtnl, req, 0, &reply);
d1ca51b1 TG	57	if (r < 0)
d1ca51b1 TG	58	return r;
d1ca51b1	59
1c4baffc	60	for (m = reply; m; m = sd_netlink_message_next(m)) {
e80af1bd	61	struct local_address *a;
d1ca51b1	62	unsigned char flags;
5502f0d9	63	uint16_t type;
1d050e1e	64	int ifi, family;
d1ca51b1	65
1c4baffc	66	r = sd_netlink_message_get_errno(m);
d1ca51b1 TG	67	if (r < 0)
	68	return r;
	69
1c4baffc	70	r = sd_netlink_message_get_type(m, &type);
d1ca51b1 TG	71	if (r < 0)
d1ca51b1 TG	72	return r;
d1ca51b1	73	if (type != RTM_NEWADDR)
8041b5ba LP	74	continue;
8041b5ba LP	75
ee8c4568 LP	76	r = sd_rtnl_message_addr_get_ifindex(m, &ifi);
	77	if (r < 0)
	78	return r;
1d050e1e LP	79	if (ifindex > 0 && ifi != ifindex)
1d050e1e LP	80	continue;
ee8c4568	81
1d050e1e LP	82	r = sd_rtnl_message_addr_get_family(m, &family);
	83	if (r < 0)
	84	return r;
	85	if (af != AF_UNSPEC && af != family)
ee8c4568 LP	86	continue;
ee8c4568 LP	87
5502f0d9	88	r = sd_rtnl_message_addr_get_flags(m, &flags);
d1ca51b1 TG	89	if (r < 0)
d1ca51b1 TG	90	return r;
5502f0d9	91	if (flags & IFA_F_DEPRECATED)
d73c3269	92	continue;
8041b5ba	93
e9140aff	94	if (!GREEDY_REALLOC0(list, n_allocated, n_list+1))
5502f0d9 LP	95	return -ENOMEM;
	96
	97	a = list + n_list;
	98
	99	r = sd_rtnl_message_addr_get_scope(m, &a->scope);
d1ca51b1 TG	100	if (r < 0)
d1ca51b1 TG	101	return r;
8041b5ba	102
945c2931	103	if (ifindex == 0 && IN_SET(a->scope, RT_SCOPE_HOST, RT_SCOPE_NOWHERE))
d73c3269	104	continue;
8041b5ba	105
1d050e1e	106	switch (family) {
5502f0d9	107
d1ca51b1	108	case AF_INET:
1c4baffc	109	r = sd_netlink_message_read_in_addr(m, IFA_LOCAL, &a->address.in);
d1ca51b1	110	if (r < 0) {
1c4baffc	111	r = sd_netlink_message_read_in_addr(m, IFA_ADDRESS, &a->address.in);
d1ca51b1 TG	112	if (r < 0)
	113	continue;
	114	}
	115	break;
5502f0d9	116
d1ca51b1	117	case AF_INET6:
1c4baffc	118	r = sd_netlink_message_read_in6_addr(m, IFA_LOCAL, &a->address.in6);
d1ca51b1	119	if (r < 0) {
1c4baffc	120	r = sd_netlink_message_read_in6_addr(m, IFA_ADDRESS, &a->address.in6);
d1ca51b1 TG	121	if (r < 0)
	122	continue;
	123	}
	124	break;
5502f0d9	125
d1ca51b1	126	default:
d73c3269	127	continue;
d73c3269	128	}
8041b5ba	129
ee8c4568	130	a->ifindex = ifi;
1d050e1e	131	a->family = family;
8041b5ba	132
d1ca51b1	133	n_list++;
5502f0d9	134	};
8041b5ba	135
c3a8c6aa LP	136	if (ret) {
	137	typesafe_qsort(list, n_list, address_compare);
	138	*ret = TAKE_PTR(list);
	139	}
e9140aff LP	140
	141	return (int) n_list;
	142	}
	143
bff94a84 YW	144	static int add_local_gateway(
	145	struct local_address **list,
	146	size_t *n_list,
	147	size_t *n_allocated,
	148	int af,
	149	int ifindex,
	150	uint32_t metric,
	151	const RouteVia *via) {
	152
	153	assert(list);
	154	assert(n_list);
	155	assert(n_allocated);
	156	assert(via);
	157
	158	if (af != AF_UNSPEC && af != via->family)
	159	return 0;
	160
	161	if (!GREEDY_REALLOC(list, n_allocated, *n_list + 1))
	162	return -ENOMEM;
	163
	164	(list)[(n_list)++] = (struct local_address) {
	165	.ifindex = ifindex,
	166	.metric = metric,
	167	.family = via->family,
	168	.address = via->address,
	169	};
	170
	171	return 0;
	172	}
	173
1c4baffc	174	int local_gateways(sd_netlink context, int ifindex, int af, struct local_address *ret) {
4afd3348 LP	175	_cleanup_(sd_netlink_message_unrefp) sd_netlink_message req = NULL, reply = NULL;
4afd3348 LP	176	_cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;
e9140aff	177	_cleanup_free_ struct local_address *list = NULL;
e9140aff LP	178	size_t n_list = 0, n_allocated = 0;
	179	int r;
	180
e9140aff	181	if (context)
1c4baffc	182	rtnl = sd_netlink_ref(context);
e9140aff	183	else {
1c4baffc	184	r = sd_netlink_open(&rtnl);
e9140aff LP	185	if (r < 0)
	186	return r;
	187	}
	188
1d050e1e	189	r = sd_rtnl_message_new_route(rtnl, &req, RTM_GETROUTE, af, RTPROT_UNSPEC);
e9140aff LP	190	if (r < 0)
	191	return r;
	192
1c4baffc	193	r = sd_netlink_message_request_dump(req, true);
e9140aff LP	194	if (r < 0)
	195	return r;
	196
1c4baffc	197	r = sd_netlink_call(rtnl, req, 0, &reply);
e9140aff LP	198	if (r < 0)
	199	return r;
	200
bff94a84 YW	201	for (sd_netlink_message *m = reply; m; m = sd_netlink_message_next(m)) {
	202	_cleanup_ordered_set_free_free_ OrderedSet *multipath_routes = NULL;
	203	_cleanup_free_ void *rta_multipath = NULL;
	204	union in_addr_union gateway;
e9140aff	205	uint16_t type;
d1b014df	206	unsigned char dst_len, src_len, table;
d2f4a948	207	uint32_t ifi = 0, metric = 0;
bff94a84	208	size_t rta_len;
1d050e1e	209	int family;
bff94a84	210	RouteVia via;
e9140aff	211
1c4baffc	212	r = sd_netlink_message_get_errno(m);
e9140aff LP	213	if (r < 0)
	214	return r;
	215
1c4baffc	216	r = sd_netlink_message_get_type(m, &type);
e9140aff LP	217	if (r < 0)
e9140aff LP	218	return r;
e9140aff LP	219	if (type != RTM_NEWROUTE)
	220	continue;
	221
a98433c0	222	/* We only care for default routes */
584d0d2a	223	r = sd_rtnl_message_route_get_dst_prefixlen(m, &dst_len);
e9140aff LP	224	if (r < 0)
e9140aff LP	225	return r;
e9140aff LP	226	if (dst_len != 0)
	227	continue;
	228
584d0d2a	229	r = sd_rtnl_message_route_get_src_prefixlen(m, &src_len);
a98433c0 LP	230	if (r < 0)
	231	return r;
	232	if (src_len != 0)
	233	continue;
	234
d1b014df LP	235	r = sd_rtnl_message_route_get_table(m, &table);
	236	if (r < 0)
	237	return r;
	238	if (table != RT_TABLE_MAIN)
	239	continue;
	240
bff94a84 YW	241	r = sd_netlink_message_read_u32(m, RTA_PRIORITY, &metric);
bff94a84 YW	242	if (r < 0 && r != -ENODATA)
e9140aff	243	return r;
e9140aff	244
1d050e1e LP	245	r = sd_rtnl_message_route_get_family(m, &family);
	246	if (r < 0)
	247	return r;
bff94a84	248	if (!IN_SET(family, AF_INET, AF_INET6))
1d050e1e LP	249	continue;
1d050e1e LP	250
bff94a84 YW	251	r = sd_netlink_message_read_u32(m, RTA_OIF, &ifi);
	252	if (r < 0 && r != -ENODATA)
	253	return r;
	254	if (r >= 0) {
	255	if (ifi <= 0)
	256	return -EINVAL;
	257	if (ifindex > 0 && (int) ifi != ifindex)
	258	continue;
e9140aff	259
bff94a84 YW	260	r = netlink_message_read_in_addr_union(m, RTA_GATEWAY, family, &gateway);
	261	if (r < 0 && r != -ENODATA)
	262	return r;
	263	if (r >= 0) {
	264	via.family = family;
	265	via.address = gateway;
	266	r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &via);
	267	if (r < 0)
	268	return r;
e9140aff	269
e9140aff	270	continue;
bff94a84	271	}
e9140aff	272
bff94a84	273	if (family != AF_INET)
e9140aff LP	274	continue;
e9140aff LP	275
bff94a84 YW	276	r = sd_netlink_message_read(m, RTA_VIA, sizeof(via), &via);
	277	if (r < 0 && r != -ENODATA)
	278	return r;
	279	if (r >= 0) {
	280	r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &via);
	281	if (r < 0)
	282	return r;
	283
	284	continue;
	285	}
e9140aff LP	286	}
e9140aff LP	287
bff94a84 YW	288	r = sd_netlink_message_read_data(m, RTA_MULTIPATH, &rta_len, &rta_multipath);
	289	if (r < 0 && r != -ENODATA)
	290	return r;
	291	if (r >= 0) {
	292	MultipathRoute *mr;
e9140aff	293
bff94a84 YW	294	r = rtattr_read_nexthop(rta_multipath, rta_len, family, &multipath_routes);
	295	if (r < 0)
	296	return r;
e9140aff	297
bff94a84 YW	298	ORDERED_SET_FOREACH(mr, multipath_routes) {
	299	if (ifindex > 0 && mr->ifindex != ifindex)
	300	continue;
	301
	302	r = add_local_gateway(&list, &n_list, &n_allocated, af, ifi, metric, &mr->gateway);
	303	if (r < 0)
	304	return r;
	305	}
	306	}
e9140aff LP	307	}
e9140aff LP	308
c3a8c6aa LP	309	if (ret) {
	310	typesafe_qsort(list, n_list, address_compare);
	311	*ret = TAKE_PTR(list);
	312	}
d73c3269	313
e80af1bd	314	return (int) n_list;
8041b5ba	315	}