shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2025-02-10 17:57:40 +03:00
Code

Merge pull request #11208 from thom311/dhcp-router-option-list

Browse Source 
dhcp: have DHCP library support multiple router entries in Router option (3)
This commit is contained in:
Lennart Poettering 2019-02-18 15:51:30 +01:00 committed by GitHub
commit c014a33fac
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
11 changed files with 124 additions and 102 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
src/basic/in-addr-util.c
View File

@ -68,6 +68,14 @@ bool in4_addr_is_localhost(const struct in_addr *a) {
return (be32toh(a->s_addr) & UINT32_C(0xFF000000)) == UINT32_C(127) << 24;
}
bool in4_addr_is_non_local(const struct in_addr *a) {
/* Whether the address is not null and not localhost.
*
* As such, it is suitable to configure as DNS/NTP server from DHCP. */
return !in4_addr_is_null(a) &&
!in4_addr_is_localhost(a);
}
int in_addr_is_localhost(int family, const union in_addr_union *u) {
assert(u);

2
src/basic/in-addr-util.h
View File

@ -30,6 +30,8 @@ int in_addr_is_link_local(int family, const union in_addr_union *u);
bool in4_addr_is_localhost(const struct in_addr *a);
int in_addr_is_localhost(int family, const union in_addr_union *u);
bool in4_addr_is_non_local(const struct in_addr *a);
int in_addr_equal(int family, const union in_addr_union *a, const union in_addr_union *b);
int in_addr_prefix_intersect(int family, const union in_addr_union *a, unsigned aprefixlen, const union in_addr_union *b, unsigned bprefixlen);
int in_addr_prefix_next(int family, union in_addr_union *u, unsigned prefixlen);

4
src/libsystemd-network/dhcp-lease-internal.h
View File

@ -41,7 +41,6 @@ struct sd_dhcp_lease {
/* each 0 if unset */
be32_t address;
be32_t server_address;
be32_t router;
be32_t next_server;
bool have_subnet_mask;
@ -50,6 +49,9 @@ struct sd_dhcp_lease {
bool have_broadcast;
be32_t broadcast;
struct in_addr *router;
size_t router_size;
struct in_addr *dns;
size_t dns_size;

36
src/libsystemd-network/network-internal.c
View File

@ -414,16 +414,33 @@ int config_parse_bridge_port_priority(
return 0;
}
void serialize_in_addrs(FILE *f, const struct in_addr *addresses, size_t size) {
unsigned i;
size_t serialize_in_addrs(FILE *f,
const struct in_addr *addresses,
size_t size,
bool with_leading_space,
bool (*predicate)(const struct in_addr *addr)) {
size_t count;
size_t i;
assert(f);
assert(addresses);
assert(size);
for (i = 0; i < size; i++)
fprintf(f, "%s%s", inet_ntoa(addresses[i]),
(i < (size - 1)) ? " ": "");
count = 0;
for (i = 0; i < size; i++) {
char sbuf[INET_ADDRSTRLEN];
if (predicate && !predicate(&addresses[i]))
continue;
if (with_leading_space)
fputc(' ', f);
else
with_leading_space = true;
fputs(inet_ntop(AF_INET, &addresses[i], sbuf, sizeof(sbuf)), f);
count++;
}
return count;
}
int deserialize_in_addrs(struct in_addr **ret, const char *string) {
@ -457,7 +474,7 @@ int deserialize_in_addrs(struct in_addr **ret, const char *string) {
size++;
}
*ret = TAKE_PTR(addresses);
*ret = size > 0 ? TAKE_PTR(addresses) : NULL;
return size;
}
@ -526,6 +543,7 @@ void serialize_dhcp_routes(FILE *f, const char *key, sd_dhcp_route **routes, siz
fprintf(f, "%s=", key);
for (i = 0; i < size; i++) {
char sbuf[INET_ADDRSTRLEN];
struct in_addr dest, gw;
uint8_t length;
@ -533,8 +551,8 @@ void serialize_dhcp_routes(FILE *f, const char *key, sd_dhcp_route **routes, siz
assert_se(sd_dhcp_route_get_gateway(routes[i], &gw) >= 0);
assert_se(sd_dhcp_route_get_destination_prefix_length(routes[i], &length) >= 0);
fprintf(f, "%s/%" PRIu8, inet_ntoa(dest), length);
fprintf(f, ",%s%s", inet_ntoa(gw), (i < (size - 1)) ? " ": "");
fprintf(f, "%s/%" PRIu8, inet_ntop(AF_INET, &dest, sbuf, sizeof(sbuf)), length);
fprintf(f, ",%s%s", inet_ntop(AF_INET, &gw, sbuf, sizeof(sbuf)), (i < (size - 1)) ? " ": "");
}
fputs("\n", f);

6
src/libsystemd-network/network-internal.h
View File

@ -40,7 +40,11 @@ CONFIG_PARSER_PROTOTYPE(config_parse_bridge_port_priority);
int net_get_unique_predictable_data(sd_device *device, uint64_t *result);
const char *net_get_name(sd_device *device);
void serialize_in_addrs(FILE *f, const struct in_addr *addresses, size_t size);
size_t serialize_in_addrs(FILE *f,
const struct in_addr *addresses,
size_t size,
bool with_leading_space,
bool (*predicate)(const struct in_addr *addr));
int deserialize_in_addrs(struct in_addr **addresses, const char *string);
void serialize_in6_addrs(FILE *f, const struct in6_addr *addresses,
size_t size);

75
src/libsystemd-network/sd-dhcp-lease.c
View File

@ -151,15 +151,15 @@ int sd_dhcp_lease_get_root_path(sd_dhcp_lease *lease, const char **root_path) {
return 0;
}
int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, struct in_addr *addr) {
int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, const struct in_addr **addr) {
assert_return(lease, -EINVAL);
assert_return(addr, -EINVAL);
if (lease->router == 0)
if (lease->router_size <= 0)
return -ENODATA;
addr->s_addr = lease->router;
return 0;
*addr = lease->router;
return (int) lease->router_size;
}
int sd_dhcp_lease_get_netmask(sd_dhcp_lease *lease, struct in_addr *addr) {
@ -261,6 +261,7 @@ static sd_dhcp_lease *dhcp_lease_free(sd_dhcp_lease *lease) {
}
free(lease->root_path);
free(lease->router);
free(lease->timezone);
free(lease->hostname);
free(lease->domainname);
@ -370,23 +371,6 @@ static int lease_parse_domain(const uint8_t *option, size_t len, char **ret) {
return 0;
}
static void filter_bogus_addresses(struct in_addr *addresses, size_t *n) {
size_t i, j;
/* Silently filter DNS/NTP servers supplied to us that do not make outside of the local scope. */
for (i = 0, j = 0; i < *n; i ++) {
if (in4_addr_is_null(addresses+i) ||
in4_addr_is_localhost(addresses+i))
continue;
addresses[j++] = addresses[i];
}
*n = j;
}
static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_addr **ret, size_t *n_ret) {
assert(option);
assert(ret);
@ -408,8 +392,6 @@ static int lease_parse_in_addrs(const uint8_t *option, size_t len, struct in_add
if (!addresses)
return -ENOMEM;
filter_bogus_addresses(addresses, &n_addresses);
free(*ret);
*ret = addresses;
*n_ret = n_addresses;
@ -554,11 +536,9 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const void *option, void
break;
case SD_DHCP_OPTION_ROUTER:
if (len >= 4) {
r = lease_parse_be32(option, 4, &lease->router);
if (r < 0)
log_debug_errno(r, "Failed to parse router address, ignoring: %m");
}
r = lease_parse_in_addrs(option, len, &lease->router, &lease->router_size);
if (r < 0)
log_debug_errno(r, "Failed to parse router addresses, ignoring: %m");
break;
case SD_DHCP_OPTION_DOMAIN_NAME_SERVER:
@ -820,7 +800,6 @@ int dhcp_lease_new(sd_dhcp_lease **ret) {
if (!lease)
return -ENOMEM;
lease->router = INADDR_ANY;
lease->n_ref = 1;
*ret = lease;
@ -835,6 +814,7 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
const struct in_addr *addresses;
const void *client_id, *data;
size_t client_id_len, data_len;
char sbuf[INET_ADDRSTRLEN];
const char *string;
uint16_t mtu;
_cleanup_free_ sd_dhcp_route **routes = NULL;
@ -857,27 +837,30 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
r = sd_dhcp_lease_get_address(lease, &address);
if (r >= 0)
fprintf(f, "ADDRESS=%s\n", inet_ntoa(address));
fprintf(f, "ADDRESS=%s\n", inet_ntop(AF_INET, &address, sbuf, sizeof(sbuf)));
r = sd_dhcp_lease_get_netmask(lease, &address);
if (r >= 0)
fprintf(f, "NETMASK=%s\n", inet_ntoa(address));
fprintf(f, "NETMASK=%s\n", inet_ntop(AF_INET, &address, sbuf, sizeof(sbuf)));
r = sd_dhcp_lease_get_router(lease, &address);
if (r >= 0)
fprintf(f, "ROUTER=%s\n", inet_ntoa(address));
r = sd_dhcp_lease_get_router(lease, &addresses);
if (r > 0) {
fputs("ROUTER=", f);
serialize_in_addrs(f, addresses, r, false, NULL);
fputc('\n', f);
}
r = sd_dhcp_lease_get_server_identifier(lease, &address);
if (r >= 0)
fprintf(f, "SERVER_ADDRESS=%s\n", inet_ntoa(address));
fprintf(f, "SERVER_ADDRESS=%s\n", inet_ntop(AF_INET, &address, sbuf, sizeof(sbuf)));
r = sd_dhcp_lease_get_next_server(lease, &address);
if (r >= 0)
fprintf(f, "NEXT_SERVER=%s\n", inet_ntoa(address));
fprintf(f, "NEXT_SERVER=%s\n", inet_ntop(AF_INET, &address, sbuf, sizeof(sbuf)));
r = sd_dhcp_lease_get_broadcast(lease, &address);
if (r >= 0)
fprintf(f, "BROADCAST=%s\n", inet_ntoa(address));
fprintf(f, "BROADCAST=%s\n", inet_ntop(AF_INET, &address, sbuf, sizeof(sbuf)));
r = sd_dhcp_lease_get_mtu(lease, &mtu);
if (r >= 0)
@ -898,15 +881,15 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
r = sd_dhcp_lease_get_dns(lease, &addresses);
if (r > 0) {
fputs("DNS=", f);
serialize_in_addrs(f, addresses, r);
fputs("\n", f);
serialize_in_addrs(f, addresses, r, false, NULL);
fputc('\n', f);
}
r = sd_dhcp_lease_get_ntp(lease, &addresses);
if (r > 0) {
fputs("NTP=", f);
serialize_in_addrs(f, addresses, r);
fputs("\n", f);
serialize_in_addrs(f, addresses, r, false, NULL);
fputc('\n', f);
}
r = sd_dhcp_lease_get_domainname(lease, &string);
@ -917,7 +900,7 @@ int dhcp_lease_save(sd_dhcp_lease *lease, const char *lease_file) {
if (r > 0) {
fputs("DOMAIN_SEARCH_LIST=", f);
fputstrv(f, search_domains, NULL, NULL);
fputs("\n", f);
fputc('\n', f);
}
r = sd_dhcp_lease_get_hostname(lease, &string);
@ -1080,9 +1063,11 @@ int dhcp_lease_load(sd_dhcp_lease **ret, const char *lease_file) {
}
if (router) {
r = inet_pton(AF_INET, router, &lease->router);
if (r <= 0)
log_debug("Failed to parse router %s, ignoring.", router);
r = deserialize_in_addrs(&lease->router, router);
if (r < 0)
log_debug_errno(r, "Failed to deserialize router addresses %s, ignoring: %m", router);
else
lease->router_size = r;
}
if (netmask) {

7
src/libsystemd-network/test-dhcp-client.c
View File

@ -423,6 +423,7 @@ static void test_addr_acq_acquired(sd_dhcp_client *client, int event,
sd_event *e = userdata;
sd_dhcp_lease *lease;
struct in_addr addr;
const struct in_addr *addrs;
assert_se(client);
assert_se(event == SD_DHCP_CLIENT_EVENT_IP_ACQUIRE);
@ -438,9 +439,9 @@ static void test_addr_acq_acquired(sd_dhcp_client *client, int event,
assert_se(memcmp(&addr.s_addr, &test_addr_acq_ack[285],
sizeof(addr.s_addr)) == 0);
assert_se(sd_dhcp_lease_get_router(lease, &addr) >= 0);
assert_se(memcmp(&addr.s_addr, &test_addr_acq_ack[308],
sizeof(addr.s_addr)) == 0);
assert_se(sd_dhcp_lease_get_router(lease, &addrs) == 1);
assert_se(memcmp(&addrs[0].s_addr, &test_addr_acq_ack[308],
sizeof(addrs[0].s_addr)) == 0);
if (verbose)
printf(" DHCP address acquired\n");

37
src/network/networkd-dhcp4.c
View File

@ -51,7 +51,8 @@ static int route_scope_from_address(const Route *route, const struct in_addr *se
static int link_set_dhcp_routes(Link *link) {
_cleanup_free_ sd_dhcp_route **static_routes = NULL;
bool classless_route = false, static_route = false;
struct in_addr gateway, address;
const struct in_addr *router;
struct in_addr address;
int r, n, i;
uint32_t table;
@ -118,18 +119,18 @@ static int link_set_dhcp_routes(Link *link) {
link->dhcp4_messages++;
}
r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway);
if (r == -ENODATA)
log_link_info_errno(link, r, "DHCP: No gateway received from DHCP server: %m");
else if (r < 0)
r = sd_dhcp_lease_get_router(link->dhcp_lease, &router);
if (r < 0 && r != -ENODATA)
log_link_warning_errno(link, r, "DHCP error: could not get gateway: %m");
else if (r <= 0 || in4_addr_is_null(&router[0]))
log_link_info_errno(link, r, "DHCP: No gateway received from DHCP server: %m");
/* According to RFC 3442: If the DHCP server returns both a Classless Static Routes option and
a Router option, the DHCP client MUST ignore the Router option. */
if (classless_route && static_route)
log_link_warning(link, "Classless static routes received from DHCP server: ignoring static-route option and router option");
if (r >= 0 && !classless_route) {
if (r > 0 && !classless_route && !in4_addr_is_null(&router[0])) {
_cleanup_(route_freep) Route *route = NULL, *route_gw = NULL;
r = route_new(&route_gw);
@ -140,7 +141,7 @@ static int link_set_dhcp_routes(Link *link) {
* route for the gw host so that we can route no matter the
* netmask or existing kernel route tables. */
route_gw->family = AF_INET;
route_gw->dst.in = gateway;
route_gw->dst.in = router[0];
route_gw->dst_prefixlen = 32;
route_gw->prefsrc.in = address;
route_gw->scope = RT_SCOPE_LINK;
@ -159,7 +160,7 @@ static int link_set_dhcp_routes(Link *link) {
return log_link_error_errno(link, r, "Could not allocate route: %m");
route->family = AF_INET;
route->gw.in = gateway;
route->gw.in = router[0];
route->prefsrc.in = address;
route->protocol = RTPROT_DHCP;
route->priority = link->network->dhcp_route_metric;
@ -180,9 +181,9 @@ static int link_set_dhcp_routes(Link *link) {
static int dhcp_lease_lost(Link *link) {
_cleanup_(address_freep) Address *address = NULL;
const struct in_addr *router;
struct in_addr addr;
struct in_addr netmask;
struct in_addr gateway;
unsigned prefixlen = 0;
int r;
@ -215,15 +216,15 @@ static int dhcp_lease_lost(Link *link) {
r = address_new(&address);
if (r >= 0) {
r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway);
if (r >= 0) {
r = sd_dhcp_lease_get_router(link->dhcp_lease, &router);
if (r > 0 && !in4_addr_is_null(&router[0])) {
_cleanup_(route_freep) Route *route_gw = NULL;
_cleanup_(route_freep) Route *route = NULL;
r = route_new(&route_gw);
if (r >= 0) {
route_gw->family = AF_INET;
route_gw->dst.in = gateway;
route_gw->dst.in = router[0];
route_gw->dst_prefixlen = 32;
route_gw->scope = RT_SCOPE_LINK;
@ -233,7 +234,7 @@ static int dhcp_lease_lost(Link *link) {
r = route_new(&route);
if (r >= 0) {
route->family = AF_INET;
route->gw.in = gateway;
route->gw.in = router[0];
route_remove(route, link, NULL);
}
@ -392,10 +393,10 @@ static int dhcp_lease_renew(sd_dhcp_client *client, Link *link) {
}
static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
const struct in_addr *router;
sd_dhcp_lease *lease;
struct in_addr address;
struct in_addr netmask;
struct in_addr gateway;
unsigned prefixlen;
uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME;
int r;
@ -417,20 +418,20 @@ static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
prefixlen = in4_addr_netmask_to_prefixlen(&netmask);
r = sd_dhcp_lease_get_router(lease, &gateway);
r = sd_dhcp_lease_get_router(lease, &router);
if (r < 0 && r != -ENODATA)
return log_link_error_errno(link, r, "DHCP error: Could not get gateway: %m");
if (r >= 0)
if (r > 0 && !in4_addr_is_null(&router[0]))
log_struct(LOG_INFO,
LOG_LINK_INTERFACE(link),
LOG_LINK_MESSAGE(link, "DHCPv4 address %u.%u.%u.%u/%u via %u.%u.%u.%u",
ADDRESS_FMT_VAL(address),
prefixlen,
ADDRESS_FMT_VAL(gateway)),
ADDRESS_FMT_VAL(router[0])),
"ADDRESS=%u.%u.%u.%u", ADDRESS_FMT_VAL(address),
"PREFIXLEN=%u", prefixlen,
"GATEWAY=%u.%u.%u.%u", ADDRESS_FMT_VAL(gateway));
"GATEWAY=%u.%u.%u.%u", ADDRESS_FMT_VAL(router[0]));
else
log_struct(LOG_INFO,
LOG_LINK_INTERFACE(link),

36
src/network/networkd-link.c
View File

@ -1058,7 +1058,7 @@ static int link_push_uplink_dns_to_dhcp_server(Link *link, sd_dhcp_server *s) {
if (link->network->dhcp_use_dns && link->dhcp_lease) {
const struct in_addr *da = NULL;
int n;
int j, n;
n = sd_dhcp_lease_get_dns(link->dhcp_lease, &da);
if (n > 0) {
@ -1066,8 +1066,9 @@ static int link_push_uplink_dns_to_dhcp_server(Link *link, sd_dhcp_server *s) {
if (!GREEDY_REALLOC(addresses, n_allocated, n_addresses + n))
return log_oom();
memcpy(addresses + n_addresses, da, n * sizeof(struct in_addr));
n_addresses += n;
for (j = 0; j < n; j++)
if (in4_addr_is_non_local(&da[j]))
addresses[n_addresses++] = da[j];
}
}
@ -1106,7 +1107,7 @@ static int link_push_uplink_ntp_to_dhcp_server(Link *link, sd_dhcp_server *s) {
if (link->network->dhcp_use_ntp && link->dhcp_lease) {
const struct in_addr *da = NULL;
int n;
int j, n;
n = sd_dhcp_lease_get_ntp(link->dhcp_lease, &da);
if (n > 0) {
@ -1114,8 +1115,9 @@ static int link_push_uplink_ntp_to_dhcp_server(Link *link, sd_dhcp_server *s) {
if (!GREEDY_REALLOC(addresses, n_allocated, n_addresses + n))
return log_oom();
memcpy(addresses + n_addresses, da, n * sizeof(struct in_addr));
n_addresses += n;
for (j = 0; j < n; j++)
if (in4_addr_is_non_local(&da[j]))
addresses[n_addresses++] = da[j];
}
}
@ -4004,12 +4006,9 @@ int link_save(Link *link) {
const struct in_addr *addresses;
r = sd_dhcp_lease_get_dns(link->dhcp_lease, &addresses);
if (r > 0) {
if (space)
fputc(' ', f);
serialize_in_addrs(f, addresses, r);
space = true;
}
if (r > 0)
if (serialize_in_addrs(f, addresses, r, space, in4_addr_is_non_local) > 0)
space = true;
}
if (link->network->dhcp_use_dns && dhcp6_lease) {
@ -4050,12 +4049,9 @@ int link_save(Link *link) {
const struct in_addr *addresses;
r = sd_dhcp_lease_get_ntp(link->dhcp_lease, &addresses);
if (r > 0) {
if (space)
fputc(' ', f);
serialize_in_addrs(f, addresses, r);
space = true;
}
if (r > 0)
if (serialize_in_addrs(f, addresses, r, space, in4_addr_is_non_local) > 0)
space = true;
}
if (link->network->dhcp_use_ntp && dhcp6_lease) {
@ -4200,7 +4196,7 @@ int link_save(Link *link) {
r = sd_dhcp_lease_get_address(link->dhcp_lease, &address);
if (r >= 0) {
fputs("DHCP4_ADDRESS=", f);
serialize_in_addrs(f, &address, 1);
serialize_in_addrs(f, &address, 1, false, NULL);
fputc('\n', f);
}
@ -4220,7 +4216,7 @@ int link_save(Link *link) {
r = sd_ipv4ll_get_address(link->ipv4ll, &address);
if (r >= 0) {
fputs("IPV4LL_ADDRESS=", f);
serialize_in_addrs(f, &address, 1);
serialize_in_addrs(f, &address, 1, false, NULL);
fputc('\n', f);
}
}

13
src/network/networkd-manager.c
View File

@ -1044,14 +1044,19 @@ static int ordered_set_put_in4_addr(OrderedSet *s, const struct in_addr *address
return r;
}
static int ordered_set_put_in4_addrv(OrderedSet *s, const struct in_addr *addresses, unsigned n) {
static int ordered_set_put_in4_addrv(OrderedSet *s,
const struct in_addr *addresses,
size_t n,
bool (*predicate)(const struct in_addr *addr)) {
int r, c = 0;
unsigned i;
size_t i;
assert(s);
assert(n == 0 || addresses);
for (i = 0; i < n; i++) {
if (predicate && !predicate(&addresses[i]))
continue;
r = ordered_set_put_in4_addr(s, addresses+i);
if (r < 0)
return r;
@ -1144,7 +1149,7 @@ static int manager_save(Manager *m) {
r = sd_dhcp_lease_get_dns(link->dhcp_lease, &addresses);
if (r > 0) {
r = ordered_set_put_in4_addrv(dns, addresses, r);
r = ordered_set_put_in4_addrv(dns, addresses, r, in4_addr_is_non_local);
if (r < 0)
return r;
} else if (r < 0 && r != -ENODATA)
@ -1156,7 +1161,7 @@ static int manager_save(Manager *m) {
r = sd_dhcp_lease_get_ntp(link->dhcp_lease, &addresses);
if (r > 0) {
r = ordered_set_put_in4_addrv(ntp, addresses, r);
r = ordered_set_put_in4_addrv(ntp, addresses, r, in4_addr_is_non_local);
if (r < 0)
return r;
} else if (r < 0 && r != -ENODATA)

2
src/systemd/sd-dhcp-lease.h
View File

@ -39,7 +39,7 @@ int sd_dhcp_lease_get_t1(sd_dhcp_lease *lease, uint32_t *t1);
int sd_dhcp_lease_get_t2(sd_dhcp_lease *lease, uint32_t *t2);
int sd_dhcp_lease_get_broadcast(sd_dhcp_lease *lease, struct in_addr *addr);
int sd_dhcp_lease_get_netmask(sd_dhcp_lease *lease, struct in_addr *addr);
int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, struct in_addr *addr);
int sd_dhcp_lease_get_router(sd_dhcp_lease *lease, const struct in_addr **addr);
int sd_dhcp_lease_get_next_server(sd_dhcp_lease *lease, struct in_addr *addr);
int sd_dhcp_lease_get_server_identifier(sd_dhcp_lease *lease, struct in_addr *addr);
int sd_dhcp_lease_get_dns(sd_dhcp_lease *lease, const struct in_addr **addr);