resolved-link.c revision 57f5ad3149b604d07816da61e6aa7dcf1cc56b64
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2014 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <net/if.h>
#include "sd-network.h"
#include "strv.h"
#include "resolved-link.h"
static void link_address_add_rrs(LinkAddress *a);
int link_new(Manager *m, Link **ret, int ifindex) {
_cleanup_(link_freep) Link *l = NULL;
int r;
assert(m);
assert(ifindex > 0);
r = hashmap_ensure_allocated(&m->links, NULL, NULL);
if (r < 0)
return r;
l = new0(Link, 1);
if (!l)
return -ENOMEM;
l->ifindex = ifindex;
r = hashmap_put(m->links, INT_TO_PTR(ifindex), l);
if (r < 0)
return r;
l->manager = m;
if (ret)
*ret = l;
l = NULL;
return 0;
}
Link *link_free(Link *l) {
if (!l)
return NULL;
while (l->addresses)
link_address_free(l->addresses);
if (l->manager)
hashmap_remove(l->manager->links, INT_TO_PTR(l->ifindex));
dns_scope_free(l->unicast_scope);
dns_scope_free(l->llmnr_ipv4_scope);
dns_scope_free(l->llmnr_ipv6_scope);
while (l->dns_servers)
dns_server_free(l->dns_servers);
free(l);
return NULL;
}
static void link_allocate_scopes(Link *l) {
int r;
assert(l);
if (l->dns_servers) {
if (!l->unicast_scope) {
r = dns_scope_new(l->manager, &l->unicast_scope, l, DNS_PROTOCOL_DNS, AF_UNSPEC);
if (r < 0)
log_warning("Failed to allocate DNS scope: %s", strerror(-r));
}
} else
l->unicast_scope = dns_scope_free(l->unicast_scope);
if (link_relevant(l, AF_INET) && (l->flags & IFF_MULTICAST) && l->manager->use_llmnr) {
if (!l->llmnr_ipv4_scope) {
r = dns_scope_new(l->manager, &l->llmnr_ipv4_scope, l, DNS_PROTOCOL_LLMNR, AF_INET);
if (r < 0)
log_warning("Failed to allocate LLMNR IPv4 scope: %s", strerror(-r));
}
} else
l->llmnr_ipv4_scope = dns_scope_free(l->llmnr_ipv4_scope);
if (link_relevant(l, AF_INET6) && (l->flags & IFF_MULTICAST) && l->manager->use_llmnr) {
if (!l->llmnr_ipv6_scope) {
r = dns_scope_new(l->manager, &l->llmnr_ipv6_scope, l, DNS_PROTOCOL_LLMNR, AF_INET6);
if (r < 0)
log_warning("Failed to allocate LLMNR IPv6 scope: %s", strerror(-r));
}
} else
l->llmnr_ipv6_scope = dns_scope_free(l->llmnr_ipv6_scope);
}
static void link_add_rrs(Link *l) {
LinkAddress *a;
LIST_FOREACH(addresses, a, l->addresses)
link_address_add_rrs(a);
}
int link_update_rtnl(Link *l, sd_rtnl_message *m) {
const char *n = NULL;
int r;
assert(l);
assert(m);
r = sd_rtnl_message_link_get_flags(m, &l->flags);
if (r < 0)
return r;
sd_rtnl_message_read_u32(m, IFLA_MTU, &l->mtu);
if (sd_rtnl_message_read_string(m, IFLA_IFNAME, &n) >= 0) {
strncpy(l->name, n, sizeof(l->name));
char_array_0(l->name);
}
link_allocate_scopes(l);
link_add_rrs(l);
return 0;
}
static int link_update_dns_servers(Link *l) {
_cleanup_strv_free_ char **nameservers = NULL;
char **nameserver;
DnsServer *s, *nx;
int r;
assert(l);
LIST_FOREACH(servers, s, l->dns_servers)
s->marked = true;
r = sd_network_get_dns(l->ifindex, &nameservers);
if (r < 0)
goto clear;
STRV_FOREACH(nameserver, nameservers) {
union in_addr_union a;
int family;
r = in_addr_from_string_auto(*nameserver, &family, &a);
if (r < 0)
goto clear;
s = link_find_dns_server(l, family, &a);
if (s)
s->marked = false;
else {
r = dns_server_new(l->manager, NULL, l, family, &a);
if (r < 0)
goto clear;
}
}
LIST_FOREACH_SAFE(servers, s, nx, l->dns_servers)
if (s->marked)
dns_server_free(s);
return 0;
clear:
while (l->dns_servers)
dns_server_free(l->dns_servers);
return r;
}
int link_update_monitor(Link *l) {
assert(l);
link_update_dns_servers(l);
link_allocate_scopes(l);
link_add_rrs(l);
return 0;
}
bool link_relevant(Link *l, int family) {
_cleanup_free_ char *state = NULL;
LinkAddress *a;
assert(l);
/* A link is relevant if it isn't a loopback device and has at
* least one relevant IP address */
if (l->flags & IFF_LOOPBACK)
return false;
sd_network_get_link_operational_state(l->ifindex, &state);
if (state && !STR_IN_SET(state, "unknown", "degraded", "routable"))
return false;
LIST_FOREACH(addresses, a, l->addresses)
if (a->family == family && link_address_relevant(a))
return true;
return false;
}
LinkAddress *link_find_address(Link *l, int family, const union in_addr_union *in_addr) {
LinkAddress *a;
assert(l);
LIST_FOREACH(addresses, a, l->addresses)
if (a->family == family && in_addr_equal(family, &a->in_addr, in_addr))
return a;
return NULL;
}
DnsServer* link_find_dns_server(Link *l, int family, const union in_addr_union *in_addr) {
DnsServer *s;
assert(l);
LIST_FOREACH(servers, s, l->dns_servers)
if (s->family == family && in_addr_equal(family, &s->address, in_addr))
return s;
return NULL;
}
DnsServer *link_get_dns_server(Link *l) {
assert(l);
if (!l->current_dns_server)
l->current_dns_server = l->dns_servers;
return l->current_dns_server;
}
void link_next_dns_server(Link *l) {
assert(l);
/* Switch to the next DNS server */
if (!l->current_dns_server) {
l->current_dns_server = l->dns_servers;
if (l->current_dns_server)
return;
}
if (!l->current_dns_server)
return;
if (l->current_dns_server->servers_next) {
l->current_dns_server = l->current_dns_server->servers_next;
return;
}
l->current_dns_server = l->dns_servers;
}
int link_address_new(Link *l, LinkAddress **ret, int family, const union in_addr_union *in_addr) {
LinkAddress *a;
assert(l);
assert(in_addr);
a = new0(LinkAddress, 1);
if (!a)
return -ENOMEM;
a->family = family;
a->in_addr = *in_addr;
a->link = l;
LIST_PREPEND(addresses, l->addresses, a);
if (ret)
*ret = a;
return 0;
}
LinkAddress *link_address_free(LinkAddress *a) {
if (!a)
return NULL;
if (a->link) {
LIST_REMOVE(addresses, a->link->addresses, a);
if (a->llmnr_address_rr) {
if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
dns_resource_record_unref(a->llmnr_address_rr);
}
if (a->llmnr_ptr_rr) {
if (a->family == AF_INET && a->link->llmnr_ipv4_scope)
dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
else if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope)
dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
dns_resource_record_unref(a->llmnr_ptr_rr);
}
}
free(a);
return NULL;
}
static void link_address_add_rrs(LinkAddress *a) {
int r;
assert(a);
if (a->family == AF_INET && a->link->llmnr_ipv4_scope) {
if (!a->link->manager->host_ipv4_key) {
a->link->manager->host_ipv4_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, a->link->manager->hostname);
if (!a->link->manager->host_ipv4_key) {
r = -ENOMEM;
goto fail;
}
}
if (!a->llmnr_address_rr) {
a->llmnr_address_rr = dns_resource_record_new(a->link->manager->host_ipv4_key);
if (!a->llmnr_address_rr) {
r = -ENOMEM;
goto fail;
}
a->llmnr_address_rr->a.in_addr = a->in_addr.in;
a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
}
if (!a->llmnr_ptr_rr) {
r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->hostname);
if (r < 0)
goto fail;
a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
}
if (link_address_relevant(a)) {
r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
if (r < 0)
goto fail;
r = dns_zone_put(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
if (r < 0)
goto fail;
} else {
dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_address_rr);
dns_zone_remove_rr(&a->link->llmnr_ipv4_scope->zone, a->llmnr_ptr_rr);
}
}
if (a->family == AF_INET6 && a->link->llmnr_ipv6_scope) {
if (!a->link->manager->host_ipv6_key) {
a->link->manager->host_ipv6_key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, a->link->manager->hostname);
if (!a->link->manager->host_ipv6_key) {
r = -ENOMEM;
goto fail;
}
}
if (!a->llmnr_address_rr) {
a->llmnr_address_rr = dns_resource_record_new(a->link->manager->host_ipv6_key);
if (!a->llmnr_address_rr) {
r = -ENOMEM;
goto fail;
}
a->llmnr_address_rr->aaaa.in6_addr = a->in_addr.in6;
a->llmnr_address_rr->ttl = LLMNR_DEFAULT_TTL;
}
if (!a->llmnr_ptr_rr) {
r = dns_resource_record_new_reverse(&a->llmnr_ptr_rr, a->family, &a->in_addr, a->link->manager->hostname);
if (r < 0)
goto fail;
a->llmnr_ptr_rr->ttl = LLMNR_DEFAULT_TTL;
}
if (link_address_relevant(a)) {
r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
if (r < 0)
goto fail;
r = dns_zone_put(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
if (r < 0)
goto fail;
} else {
dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_address_rr);
dns_zone_remove_rr(&a->link->llmnr_ipv6_scope->zone, a->llmnr_ptr_rr);
}
}
return;
fail:
log_debug("Failed to update address RRs: %s", strerror(-r));
}
int link_address_update_rtnl(LinkAddress *a, sd_rtnl_message *m) {
int r;
assert(a);
assert(m);
r = sd_rtnl_message_addr_get_flags(m, &a->flags);
if (r < 0)
return r;
sd_rtnl_message_addr_get_scope(m, &a->scope);
link_allocate_scopes(a->link);
link_add_rrs(a->link);
return 0;
}
bool link_address_relevant(LinkAddress *a) {
assert(a);
if (a->flags & IFA_F_DEPRECATED)
return false;
if (IN_SET(a->scope, RT_SCOPE_HOST, RT_SCOPE_NOWHERE))
return false;
return true;
}