Systemd/src/network/networkd-dhcp6.c
Lennart Poettering 8e766630f0 tree-wide: drop redundant _cleanup_ macros (#8810)
This drops a good number of type-specific _cleanup_ macros, and patches
all users to just use the generic ones.

In most recent code we abstained from defining type-specific macros, and
this basically removes all those added already, with the exception of
the really low-level ones.

Having explicit macros for this is not too useful, as the expression
without the extra macro is generally just 2ch wider. We should generally
emphesize generic code, unless there are really good reasons for
specific code, hence let's follow this in this case too.

Note that _cleanup_free_ and similar really low-level, libc'ish, Linux
API'ish macros continue to be defined, only the really high-level OO
ones are dropped. From now on this should really be the rule: for really
low-level stuff, such as memory allocation, fd handling and so one, go
ahead and define explicit per-type macros, but for high-level, specific
program code, just use the generic _cleanup_() macro directly, in order
to keep things simple and as readable as possible for the uninitiated.

Note that before this patch some of the APIs (notable libudev ones) were
already used with the high-level macros at some places and with the
generic _cleanup_ macro at others. With this patch we hence unify on the
latter.
2018-04-25 12:31:45 +02:00

528 lines
16 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
Copyright (C) 2014 Intel Corporation. All rights reserved.
***/
#include <netinet/ether.h>
#include <linux/if.h>
#include "sd-radv.h"
#include "sd-dhcp6-client.h"
#include "hashmap.h"
#include "hostname-util.h"
#include "network-internal.h"
#include "networkd-link.h"
#include "networkd-manager.h"
#include "siphash24.h"
#include "string-util.h"
#include "radv-internal.h"
static int dhcp6_lease_address_acquired(sd_dhcp6_client *client, Link *link);
static bool dhcp6_verify_link(Link *link) {
if (!link->network) {
log_link_info(link, "Link is not managed by us");
return false;
}
if (!IN_SET(link->network->router_prefix_delegation,
RADV_PREFIX_DELEGATION_DHCP6,
RADV_PREFIX_DELEGATION_BOTH)) {
log_link_debug(link, "Link does not request DHCPv6 prefix delegation");
return false;
}
return true;
}
static bool dhcp6_enable_prefix_delegation(Link *dhcp6_link) {
Manager *manager;
Link *l;
Iterator i;
assert(dhcp6_link);
manager = dhcp6_link->manager;
assert(manager);
HASHMAP_FOREACH(l, manager->links, i) {
if (l == dhcp6_link)
continue;
if (!dhcp6_verify_link(l))
continue;
return true;
}
return false;
}
static int dhcp6_lease_information_acquired(sd_dhcp6_client *client,
Link *link) {
return 0;
}
static int dhcp6_pd_prefix_assign(Link *link, struct in6_addr *prefix,
uint8_t prefix_len,
uint32_t lifetime_preferred,
uint32_t lifetime_valid) {
sd_radv *radv = link->radv;
int r;
_cleanup_(sd_radv_prefix_unrefp) sd_radv_prefix *p = NULL;
r = sd_radv_prefix_new(&p);
if (r < 0)
return r;
r = sd_radv_prefix_set_prefix(p, prefix, prefix_len);
if (r < 0)
return r;
r = sd_radv_prefix_set_preferred_lifetime(p, lifetime_preferred);
if (r < 0)
return r;
r = sd_radv_prefix_set_valid_lifetime(p, lifetime_valid);
if (r < 0)
return r;
r = sd_radv_stop(radv);
if (r < 0)
return r;
r = sd_radv_add_prefix(radv, p, true);
if (r < 0 && r != -EEXIST)
return r;
r = manager_dhcp6_prefix_add(link->manager, &p->opt.in6_addr, link);
if (r < 0)
return r;
return sd_radv_start(radv);
}
static Network *dhcp6_reset_pd_prefix_network(Link *link) {
assert(link);
assert(link->manager);
assert(link->manager->networks);
return link->manager->networks;
}
static int dhcp6_pd_prefix_distribute(Link *dhcp6_link, Iterator *i,
struct in6_addr *pd_prefix,
uint8_t pd_prefix_len,
uint32_t lifetime_preferred,
uint32_t lifetime_valid) {
Link *link;
Manager *manager = dhcp6_link->manager;
union in_addr_union prefix;
uint8_t n_prefixes, n_used = 0;
_cleanup_free_ char *buf = NULL;
int r;
assert(manager);
assert(pd_prefix_len <= 64);
prefix.in6 = *pd_prefix;
r = in_addr_mask(AF_INET6, &prefix, pd_prefix_len);
if (r < 0)
return r;
n_prefixes = 1 << (64 - pd_prefix_len);
(void) in_addr_to_string(AF_INET6, &prefix, &buf);
log_link_debug(dhcp6_link, "Assigning up to %u prefixes from %s/%u",
n_prefixes, strnull(buf), pd_prefix_len);
while (hashmap_iterate(manager->links, i, (void **)&link, NULL)) {
Link *assigned_link;
if (n_used == n_prefixes) {
log_link_debug(dhcp6_link, "Assigned %u/%u prefixes from %s/%u",
n_used, n_prefixes, strnull(buf), pd_prefix_len);
return -EAGAIN;
}
if (link == dhcp6_link)
continue;
if (!dhcp6_verify_link(link))
continue;
assigned_link = manager_dhcp6_prefix_get(manager, &prefix.in6);
if (assigned_link != NULL && assigned_link != link)
continue;
r = dhcp6_pd_prefix_assign(link, &prefix.in6, 64,
lifetime_preferred, lifetime_valid);
if (r < 0) {
log_link_error_errno(link, r, "Unable to %s prefix %s/%u for link: %m",
assigned_link ? "update": "assign",
strnull(buf), pd_prefix_len);
if (assigned_link == NULL)
continue;
} else
log_link_debug(link, "Assigned prefix %u/%u %s/64 to link",
n_used + 1, n_prefixes, strnull(buf));
n_used++;
r = in_addr_prefix_next(AF_INET6, &prefix, pd_prefix_len);
if (r < 0 && n_used < n_prefixes)
return r;
}
if (n_used < n_prefixes) {
Route *route;
int n = n_used;
r = route_new(&route);
if (r < 0)
return r;
while (n < n_prefixes) {
route_update(route, &prefix, pd_prefix_len, NULL, NULL,
0, 0, RTN_UNREACHABLE);
r = route_configure(route, link, NULL);
if (r < 0) {
route_free(route);
return r;
}
r = in_addr_prefix_next(AF_INET6, &prefix, pd_prefix_len);
if (r < 0)
return r;
}
}
return n_used;
}
static int dhcp6_lease_pd_prefix_acquired(sd_dhcp6_client *client, Link *link) {
int r;
sd_dhcp6_lease *lease;
struct in6_addr pd_prefix;
uint8_t pd_prefix_len;
uint32_t lifetime_preferred, lifetime_valid;
_cleanup_free_ char *buf = NULL;
Iterator i = ITERATOR_FIRST;
r = sd_dhcp6_client_get_lease(client, &lease);
if (r < 0)
return r;
(void) in_addr_to_string(AF_INET6, (union in_addr_union*) &pd_prefix, &buf);
dhcp6_reset_pd_prefix_network(link);
sd_dhcp6_lease_reset_pd_prefix_iter(lease);
while (sd_dhcp6_lease_get_pd(lease, &pd_prefix, &pd_prefix_len,
&lifetime_preferred,
&lifetime_valid) >= 0) {
if (pd_prefix_len > 64) {
log_link_debug(link, "PD Prefix length > 64, ignoring prefix %s/%u",
strnull(buf), pd_prefix_len);
continue;
}
r = dhcp6_pd_prefix_distribute(link, &i, &pd_prefix,
pd_prefix_len,
lifetime_preferred,
lifetime_valid);
if (r < 0 && r != -EAGAIN)
return r;
if (r >= 0)
i = ITERATOR_FIRST;
}
return 0;
}
static int dhcp6_address_handler(sd_netlink *rtnl, sd_netlink_message *m,
void *userdata) {
_cleanup_(link_unrefp) Link *link = userdata;
int r;
assert(link);
r = sd_netlink_message_get_errno(m);
if (r < 0 && r != -EEXIST) {
if (link->rtnl_extended_attrs) {
log_link_warning(link, "Could not set extended netlink attributes, reverting to fallback mechanism");
link->rtnl_extended_attrs = false;
dhcp6_lease_address_acquired(link->dhcp6_client, link);
return 1;
}
log_link_error_errno(link, r, "Could not set DHCPv6 address: %m");
link_enter_failed(link);
} else if (r >= 0)
manager_rtnl_process_address(rtnl, m, link->manager);
return 1;
}
static int dhcp6_address_change(
Link *link,
struct in6_addr *ip6_addr,
uint32_t lifetime_preferred,
uint32_t lifetime_valid) {
_cleanup_(address_freep) Address *addr = NULL;
char buffer[INET6_ADDRSTRLEN];
int r;
r = address_new(&addr);
if (r < 0)
return r;
addr->family = AF_INET6;
memcpy(&addr->in_addr.in6, ip6_addr, sizeof(*ip6_addr));
addr->flags = IFA_F_NOPREFIXROUTE;
addr->prefixlen = 128;
addr->cinfo.ifa_prefered = lifetime_preferred;
addr->cinfo.ifa_valid = lifetime_valid;
log_link_info(link,
"DHCPv6 address %s/%d timeout preferred %d valid %d",
inet_ntop(AF_INET6, &addr->in_addr.in6, buffer, sizeof(buffer)),
addr->prefixlen, lifetime_preferred, lifetime_valid);
r = address_configure(addr, link, dhcp6_address_handler, true);
if (r < 0)
log_link_warning_errno(link, r, "Could not assign DHCPv6 address: %m");
return r;
}
static int dhcp6_lease_address_acquired(sd_dhcp6_client *client, Link *link) {
int r;
sd_dhcp6_lease *lease;
struct in6_addr ip6_addr;
uint32_t lifetime_preferred, lifetime_valid;
r = sd_dhcp6_client_get_lease(client, &lease);
if (r < 0)
return r;
sd_dhcp6_lease_reset_address_iter(lease);
while (sd_dhcp6_lease_get_address(lease, &ip6_addr,
&lifetime_preferred,
&lifetime_valid) >= 0) {
r = dhcp6_address_change(link, &ip6_addr, lifetime_preferred, lifetime_valid);
if (r < 0)
return r;
}
return 0;
}
static void dhcp6_handler(sd_dhcp6_client *client, int event, void *userdata) {
int r;
Link *link = userdata;
assert(link);
assert(link->network);
if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
return;
switch(event) {
case SD_DHCP6_CLIENT_EVENT_STOP:
case SD_DHCP6_CLIENT_EVENT_RESEND_EXPIRE:
case SD_DHCP6_CLIENT_EVENT_RETRANS_MAX:
if (sd_dhcp6_client_get_lease(client, NULL) >= 0)
log_link_warning(link, "DHCPv6 lease lost");
(void) manager_dhcp6_prefix_remove_all(link->manager, link);
link->dhcp6_configured = false;
break;
case SD_DHCP6_CLIENT_EVENT_IP_ACQUIRE:
r = dhcp6_lease_address_acquired(client, link);
if (r < 0) {
link_enter_failed(link);
return;
}
r = dhcp6_lease_pd_prefix_acquired(client, link);
if (r < 0)
log_link_debug(link, "DHCPv6 did not receive prefixes to delegate");
_fallthrough_;
case SD_DHCP6_CLIENT_EVENT_INFORMATION_REQUEST:
r = dhcp6_lease_information_acquired(client, link);
if (r < 0) {
link_enter_failed(link);
return;
}
link->dhcp6_configured = true;
break;
default:
if (event < 0)
log_link_warning_errno(link, event, "DHCPv6 error: %m");
else
log_link_warning(link, "DHCPv6 unknown event: %d", event);
return;
}
link_check_ready(link);
}
int dhcp6_request_address(Link *link, int ir) {
int r, inf_req;
bool running;
assert(link);
assert(link->dhcp6_client);
assert(in_addr_is_link_local(AF_INET6, (const union in_addr_union*)&link->ipv6ll_address) > 0);
r = sd_dhcp6_client_is_running(link->dhcp6_client);
if (r < 0)
return r;
else
running = !!r;
if (running) {
r = sd_dhcp6_client_get_information_request(link->dhcp6_client, &inf_req);
if (r < 0)
return r;
if (inf_req == ir)
return 0;
r = sd_dhcp6_client_stop(link->dhcp6_client);
if (r < 0)
return r;
} else {
r = sd_dhcp6_client_set_local_address(link->dhcp6_client, &link->ipv6ll_address);
if (r < 0)
return r;
}
r = sd_dhcp6_client_set_information_request(link->dhcp6_client, ir);
if (r < 0)
return r;
r = sd_dhcp6_client_start(link->dhcp6_client);
if (r < 0)
return r;
return 0;
}
static int dhcp6_set_hostname(sd_dhcp6_client *client, Link *link) {
_cleanup_free_ char *hostname = NULL;
const char *hn;
int r;
assert(link);
if (!link->network->dhcp_send_hostname)
hn = NULL;
else if (link->network->dhcp_hostname)
hn = link->network->dhcp_hostname;
else {
r = gethostname_strict(&hostname);
if (r < 0 && r != -ENXIO) /* ENXIO: no hostname set or hostname is "localhost" */
return r;
hn = hostname;
}
return sd_dhcp6_client_set_fqdn(client, hn);
}
int dhcp6_configure(Link *link) {
sd_dhcp6_client *client = NULL;
const DUID *duid;
int r;
assert(link);
assert(link->network);
if (link->dhcp6_client)
return 0;
r = sd_dhcp6_client_new(&client);
if (r < 0)
return r;
r = sd_dhcp6_client_attach_event(client, NULL, 0);
if (r < 0)
goto error;
r = sd_dhcp6_client_set_mac(client,
(const uint8_t *) &link->mac,
sizeof (link->mac), ARPHRD_ETHER);
if (r < 0)
goto error;
r = sd_dhcp6_client_set_iaid(client, link->network->iaid);
if (r < 0)
goto error;
duid = link_duid(link);
r = sd_dhcp6_client_set_duid(client,
duid->type,
duid->raw_data_len > 0 ? duid->raw_data : NULL,
duid->raw_data_len);
if (r < 0)
goto error;
r = dhcp6_set_hostname(client, link);
if (r < 0)
goto error;
r = sd_dhcp6_client_set_ifindex(client, link->ifindex);
if (r < 0)
goto error;
if (link->network->rapid_commit) {
r = sd_dhcp6_client_set_request_option(client, SD_DHCP6_OPTION_RAPID_COMMIT);
if (r < 0)
goto error;
}
r = sd_dhcp6_client_set_callback(client, dhcp6_handler, link);
if (r < 0)
goto error;
if (dhcp6_enable_prefix_delegation(link)) {
r = sd_dhcp6_client_set_prefix_delegation(client, true);
if (r < 0)
goto error;
}
link->dhcp6_client = client;
return 0;
error:
sd_dhcp6_client_unref(client);
return r;
}