blob: 7be6b945f2d7165347a1a1f583da0b43d5798324 [file] [log] [blame] [raw]
/* 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;
assert(ret);
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++;
};
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;
assert(ret);
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, 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;
}
}
}
typesafe_qsort(list, n_list, address_compare);
*ret = TAKE_PTR(list);
return (int) n_list;
}