diff options
Diffstat (limited to 'src/libsystemd/sd-netlink/local-addresses.c')
-rw-r--r-- | src/libsystemd/sd-netlink/local-addresses.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/src/libsystemd/sd-netlink/local-addresses.c b/src/libsystemd/sd-netlink/local-addresses.c new file mode 100644 index 0000000..5c37279 --- /dev/null +++ b/src/libsystemd/sd-netlink/local-addresses.c @@ -0,0 +1,253 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include "sd-netlink.h" + +#include "alloc-util.h" +#include "local-addresses.h" +#include "macro.h" +#include "netlink-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; +} + +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; + sd_netlink_message *m = 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 (m = reply; m; m = sd_netlink_message_next(m)) { + struct local_address *a; + uint16_t type; + unsigned char dst_len, src_len; + uint32_t ifi; + int 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_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_netlink_message_read_u32(m, RTA_OIF, &ifi); + if (r == -ENODATA) /* Not all routes have an RTA_OIF attribute (for example nexthop ones) */ + continue; + if (r < 0) + return r; + if (ifindex > 0 && (int) ifi != ifindex) + continue; + + r = sd_rtnl_message_route_get_family(m, &family); + if (r < 0) + return r; + if (af != AF_UNSPEC && af != family) + continue; + + if (!GREEDY_REALLOC0(list, n_allocated, n_list + 1)) + return -ENOMEM; + + a = list + n_list; + + switch (family) { + case AF_INET: + r = sd_netlink_message_read_in_addr(m, RTA_GATEWAY, &a->address.in); + if (r < 0) + continue; + + break; + case AF_INET6: + r = sd_netlink_message_read_in6_addr(m, RTA_GATEWAY, &a->address.in6); + if (r < 0) + continue; + + break; + default: + continue; + } + + sd_netlink_message_read_u32(m, RTA_PRIORITY, &a->metric); + + a->ifindex = ifi; + a->family = family; + + n_list++; + } + + typesafe_qsort(list, n_list, address_compare); + + *ret = TAKE_PTR(list); + + return (int) n_list; +} |