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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 20:49:52 +0000
commit55944e5e40b1be2afc4855d8d2baf4b73d1876b5 (patch)
tree33f869f55a1b149e9b7c2b7e201867ca5dd52992 /src/network/networkd-dhcp-common.c
parentInitial commit. (diff)
downloadsystemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.tar.xz
systemd-55944e5e40b1be2afc4855d8d2baf4b73d1876b5.zip
Adding upstream version 255.4.upstream/255.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/network/networkd-dhcp-common.c')
-rw-r--r--src/network/networkd-dhcp-common.c1489
1 files changed, 1489 insertions, 0 deletions
diff --git a/src/network/networkd-dhcp-common.c b/src/network/networkd-dhcp-common.c
new file mode 100644
index 0000000..080b153
--- /dev/null
+++ b/src/network/networkd-dhcp-common.c
@@ -0,0 +1,1489 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <netinet/in.h>
+#include <linux/if_arp.h>
+
+#include "bus-error.h"
+#include "bus-locator.h"
+#include "dhcp-identifier.h"
+#include "dhcp-option.h"
+#include "dhcp6-internal.h"
+#include "escape.h"
+#include "hexdecoct.h"
+#include "in-addr-prefix-util.h"
+#include "networkd-dhcp-common.h"
+#include "networkd-link.h"
+#include "networkd-manager.h"
+#include "networkd-network.h"
+#include "networkd-route-util.h"
+#include "parse-util.h"
+#include "socket-util.h"
+#include "string-table.h"
+#include "strv.h"
+#include "vrf.h"
+
+static uint32_t link_get_vrf_table(Link *link) {
+ assert(link);
+ assert(link->network);
+
+ return link->network->vrf ? VRF(link->network->vrf)->table : RT_TABLE_MAIN;
+}
+
+uint32_t link_get_dhcp4_route_table(Link *link) {
+ assert(link);
+ assert(link->network);
+
+ /* When the interface is part of an VRF use the VRFs routing table, unless
+ * another table is explicitly specified. */
+
+ if (link->network->dhcp_route_table_set)
+ return link->network->dhcp_route_table;
+ return link_get_vrf_table(link);
+}
+
+uint32_t link_get_ipv6_accept_ra_route_table(Link *link) {
+ assert(link);
+ assert(link->network);
+
+ if (link->network->ipv6_accept_ra_route_table_set)
+ return link->network->ipv6_accept_ra_route_table;
+ return link_get_vrf_table(link);
+}
+
+bool link_dhcp_enabled(Link *link, int family) {
+ assert(link);
+ assert(IN_SET(family, AF_INET, AF_INET6));
+
+ /* Currently, sd-dhcp-client supports only ethernet and infiniband. */
+ if (family == AF_INET && !IN_SET(link->iftype, ARPHRD_ETHER, ARPHRD_INFINIBAND))
+ return false;
+
+ if (family == AF_INET6 && !socket_ipv6_is_supported())
+ return false;
+
+ if (link->flags & IFF_LOOPBACK)
+ return false;
+
+ if (link->iftype == ARPHRD_CAN)
+ return false;
+
+ if (!link->network)
+ return false;
+
+ return link->network->dhcp & (family == AF_INET ? ADDRESS_FAMILY_IPV4 : ADDRESS_FAMILY_IPV6);
+}
+
+void network_adjust_dhcp(Network *network) {
+ assert(network);
+ assert(network->dhcp >= 0);
+
+ if (network->dhcp == ADDRESS_FAMILY_NO)
+ return;
+
+ /* Bonding slave does not support addressing. */
+ if (network->bond) {
+ log_warning("%s: Cannot enable DHCP= when Bond= is specified, disabling DHCP=.",
+ network->filename);
+ network->dhcp = ADDRESS_FAMILY_NO;
+ return;
+ }
+
+ if (!FLAGS_SET(network->link_local, ADDRESS_FAMILY_IPV6) &&
+ FLAGS_SET(network->dhcp, ADDRESS_FAMILY_IPV6)) {
+ log_warning("%s: DHCPv6 client is enabled but IPv6 link-local addressing is disabled. "
+ "Disabling DHCPv6 client.", network->filename);
+ SET_FLAG(network->dhcp, ADDRESS_FAMILY_IPV6, false);
+ }
+
+ network_adjust_dhcp4(network);
+}
+
+static bool duid_needs_product_uuid(const DUID *duid) {
+ assert(duid);
+
+ return duid->type == DUID_TYPE_UUID && duid->raw_data_len == 0;
+}
+
+static const struct DUID fallback_duid = { .type = DUID_TYPE_EN };
+
+const DUID *link_get_duid(Link *link, int family) {
+ const DUID *duid;
+
+ assert(link);
+ assert(IN_SET(family, AF_INET, AF_INET6));
+
+ if (link->network) {
+ duid = family == AF_INET ? &link->network->dhcp_duid : &link->network->dhcp6_duid;
+ if (duid->type != _DUID_TYPE_INVALID) {
+ if (duid_needs_product_uuid(duid))
+ return &link->manager->duid_product_uuid;
+ else
+ return duid;
+ }
+ }
+
+ duid = family == AF_INET ? &link->manager->dhcp_duid : &link->manager->dhcp6_duid;
+ if (link->hw_addr.length == 0 && IN_SET(duid->type, DUID_TYPE_LLT, DUID_TYPE_LL))
+ /* Fallback to DUID that works without MAC address.
+ * This is useful for tunnel devices without MAC address. */
+ return &fallback_duid;
+
+ return duid;
+}
+
+static int get_product_uuid_handler(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
+ Manager *manager = ASSERT_PTR(userdata);
+ const sd_bus_error *e;
+ const void *a;
+ size_t sz;
+ int r;
+
+ assert(m);
+
+ /* To avoid calling GetProductUUID() bus method so frequently, set the flag below
+ * even if the method fails. */
+ manager->has_product_uuid = true;
+
+ e = sd_bus_message_get_error(m);
+ if (e) {
+ r = sd_bus_error_get_errno(e);
+ log_warning_errno(r, "Could not get product UUID. Falling back to use machine-app-specific ID as DUID-UUID: %s",
+ bus_error_message(e, r));
+ return 0;
+ }
+
+ r = sd_bus_message_read_array(m, 'y', &a, &sz);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to get product UUID. Falling back to use machine-app-specific ID as DUID-UUID: %m");
+ return 0;
+ }
+
+ if (sz != sizeof(sd_id128_t)) {
+ log_warning("Invalid product UUID. Falling back to use machine-app-specific ID as DUID-UUID.");
+ return 0;
+ }
+
+ log_debug("Successfully obtained product UUID");
+
+ memcpy(&manager->duid_product_uuid.raw_data, a, sz);
+ manager->duid_product_uuid.raw_data_len = sz;
+
+ return 0;
+}
+
+int manager_request_product_uuid(Manager *m) {
+ static bool bus_method_is_called = false;
+ int r;
+
+ assert(m);
+
+ if (bus_method_is_called)
+ return 0;
+
+ if (sd_bus_is_ready(m->bus) <= 0 && !m->product_uuid_requested) {
+ log_debug("Not connected to system bus, requesting product UUID later.");
+ m->product_uuid_requested = true;
+ return 0;
+ }
+
+ m->product_uuid_requested = false;
+
+ r = bus_call_method_async(
+ m->bus,
+ NULL,
+ bus_hostname,
+ "GetProductUUID",
+ get_product_uuid_handler,
+ m,
+ "b",
+ false);
+ if (r < 0)
+ return log_warning_errno(r, "Failed to get product UUID: %m");
+
+ log_debug("Requesting product UUID.");
+
+ bus_method_is_called = true;
+
+ return 0;
+}
+
+int dhcp_configure_duid(Link *link, const DUID *duid) {
+ Manager *m;
+ int r;
+
+ assert(link);
+ assert(link->manager);
+ assert(duid);
+
+ m = link->manager;
+
+ if (!duid_needs_product_uuid(duid))
+ return 1;
+
+ if (m->has_product_uuid)
+ return 1;
+
+ r = manager_request_product_uuid(m);
+ if (r < 0) {
+ log_link_warning_errno(link, r,
+ "Failed to get product UUID. Falling back to use machine-app-specific ID as DUID-UUID: %m");
+
+ m->has_product_uuid = true; /* Do not request UUID again on failure. */
+ return 1;
+ }
+
+ return 0;
+}
+
+bool address_is_filtered(int family, const union in_addr_union *address, uint8_t prefixlen, Set *allow_list, Set *deny_list) {
+ struct in_addr_prefix *p;
+
+ assert(IN_SET(family, AF_INET, AF_INET6));
+ assert(address);
+
+ if (allow_list) {
+ SET_FOREACH(p, allow_list)
+ if (p->family == family &&
+ p->prefixlen <= prefixlen &&
+ in_addr_prefix_covers(family, &p->address, p->prefixlen, address) > 0)
+ return false;
+
+ return true;
+ }
+
+ SET_FOREACH(p, deny_list)
+ if (p->family == family &&
+ in_addr_prefix_intersect(family, &p->address, p->prefixlen, address, prefixlen) > 0)
+ return true;
+
+ return false;
+}
+
+int link_get_captive_portal(Link *link, const char **ret) {
+ const char *dhcp4_cp = NULL, *dhcp6_cp = NULL, *ndisc_cp = NULL;
+ int r;
+
+ assert(link);
+
+ if (!link->network) {
+ *ret = NULL;
+ return 0;
+ }
+
+ if (link->network->dhcp_use_captive_portal && link->dhcp_lease) {
+ r = sd_dhcp_lease_get_captive_portal(link->dhcp_lease, &dhcp4_cp);
+ if (r < 0 && r != -ENODATA)
+ return r;
+ }
+
+ if (link->network->dhcp6_use_captive_portal && link->dhcp6_lease) {
+ r = sd_dhcp6_lease_get_captive_portal(link->dhcp6_lease, &dhcp6_cp);
+ if (r < 0 && r != -ENODATA)
+ return r;
+ }
+
+ if (link->network->ipv6_accept_ra_use_captive_portal) {
+ NDiscCaptivePortal *cp;
+ usec_t usec = 0;
+
+ /* Use the captive portal with the longest lifetime. */
+
+ SET_FOREACH(cp, link->ndisc_captive_portals) {
+ if (cp->lifetime_usec < usec)
+ continue;
+
+ ndisc_cp = cp->captive_portal;
+ usec = cp->lifetime_usec;
+ }
+
+ if (set_size(link->ndisc_captive_portals) > 1)
+ log_link_debug(link, "Multiple captive portals obtained by IPv6RA, using \"%s\" and ignoring others.",
+ ndisc_cp);
+ }
+
+ if (dhcp4_cp) {
+ if (dhcp6_cp && !streq(dhcp4_cp, dhcp6_cp))
+ log_link_debug(link, "DHCPv6 captive portal (%s) does not match DHCPv4 (%s), ignoring DHCPv6 captive portal.",
+ dhcp6_cp, dhcp4_cp);
+
+ if (ndisc_cp && !streq(dhcp4_cp, ndisc_cp))
+ log_link_debug(link, "IPv6RA captive portal (%s) does not match DHCPv4 (%s), ignoring IPv6RA captive portal.",
+ ndisc_cp, dhcp4_cp);
+
+ *ret = dhcp4_cp;
+ return 1;
+ }
+
+ if (dhcp6_cp) {
+ if (ndisc_cp && !streq(dhcp6_cp, ndisc_cp))
+ log_link_debug(link, "IPv6RA captive portal (%s) does not match DHCPv6 (%s), ignoring IPv6RA captive portal.",
+ ndisc_cp, dhcp6_cp);
+
+ *ret = dhcp6_cp;
+ return 1;
+ }
+
+ *ret = ndisc_cp;
+ return !!ndisc_cp;
+}
+
+int config_parse_dhcp(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ AddressFamily *dhcp = data, s;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ /* Note that this is mostly like
+ * config_parse_address_family(), except that it
+ * understands some old names for the enum values */
+
+ s = address_family_from_string(rvalue);
+ if (s < 0) {
+
+ /* Previously, we had a slightly different enum here,
+ * support its values for compatibility. */
+
+ s = dhcp_deprecated_address_family_from_string(rvalue);
+ if (s < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, s,
+ "Failed to parse DHCP option, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "DHCP=%s is deprecated, please use DHCP=%s instead.",
+ rvalue, address_family_to_string(s));
+ }
+
+ *dhcp = s;
+ return 0;
+}
+
+int config_parse_dhcp_route_metric(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ uint32_t metric;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_UNSPEC, AF_INET));
+ assert(rvalue);
+ assert(data);
+
+ r = safe_atou32(rvalue, &metric);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse RouteMetric=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_route_metric = metric;
+ network->dhcp_route_metric_set = true;
+ break;
+ case AF_UNSPEC:
+ /* For backward compatibility. */
+ if (!network->dhcp_route_metric_set)
+ network->dhcp_route_metric = metric;
+ if (!network->ipv6_accept_ra_route_metric_set) {
+ network->ipv6_accept_ra_route_metric_high = metric;
+ network->ipv6_accept_ra_route_metric_medium = metric;
+ network->ipv6_accept_ra_route_metric_low = metric;
+ }
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+
+int config_parse_ipv6_accept_ra_route_metric(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ uint32_t metric_high, metric_medium, metric_low;
+ int r, s, t;
+
+ assert(filename);
+ assert(rvalue);
+
+ if (safe_atou32(rvalue, &metric_low) >= 0)
+ metric_high = metric_medium = metric_low;
+ else {
+ _cleanup_free_ char *high = NULL, *medium = NULL, *low = NULL;
+ const char *p = rvalue;
+
+ r = extract_many_words(&p, ":", EXTRACT_DONT_COALESCE_SEPARATORS, &high, &medium, &low, NULL);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r != 3 || !isempty(p)) {
+ log_syntax(unit, LOG_WARNING, filename, line, r < 0 ? r : 0,
+ "Failed to parse RouteTable=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ r = safe_atou32(high, &metric_high);
+ s = safe_atou32(medium, &metric_medium);
+ t = safe_atou32(low, &metric_low);
+ if (r < 0 || s < 0 || t < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r < 0 ? r : s < 0 ? s : t,
+ "Failed to parse RouteTable=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ if (metric_high >= metric_medium || metric_medium >= metric_low) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Invalid RouteTable=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+ }
+
+ network->ipv6_accept_ra_route_metric_high = metric_high;
+ network->ipv6_accept_ra_route_metric_medium = metric_medium;
+ network->ipv6_accept_ra_route_metric_low = metric_low;
+ network->ipv6_accept_ra_route_metric_set = true;
+
+ return 0;
+}
+
+int config_parse_dhcp_send_hostname(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_UNSPEC, AF_INET, AF_INET6));
+ assert(rvalue);
+ assert(data);
+
+ r = parse_boolean(rvalue);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse SendHostname=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_send_hostname = r;
+ network->dhcp_send_hostname_set = true;
+ break;
+ case AF_INET6:
+ network->dhcp6_send_hostname = r;
+ network->dhcp6_send_hostname_set = true;
+ break;
+ case AF_UNSPEC:
+ /* For backward compatibility. */
+ if (!network->dhcp_send_hostname_set)
+ network->dhcp_send_hostname = r;
+ if (!network->dhcp6_send_hostname_set)
+ network->dhcp6_send_hostname = r;
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+int config_parse_dhcp_use_dns(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_UNSPEC, AF_INET, AF_INET6));
+ assert(rvalue);
+ assert(data);
+
+ r = parse_boolean(rvalue);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse UseDNS=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_use_dns = r;
+ network->dhcp_use_dns_set = true;
+ break;
+ case AF_INET6:
+ network->dhcp6_use_dns = r;
+ network->dhcp6_use_dns_set = true;
+ break;
+ case AF_UNSPEC:
+ /* For backward compatibility. */
+ if (!network->dhcp_use_dns_set)
+ network->dhcp_use_dns = r;
+ if (!network->dhcp6_use_dns_set)
+ network->dhcp6_use_dns = r;
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+
+int config_parse_dhcp_use_domains(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ DHCPUseDomains d;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_UNSPEC, AF_INET, AF_INET6));
+ assert(rvalue);
+ assert(data);
+
+ d = dhcp_use_domains_from_string(rvalue);
+ if (d < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, d,
+ "Failed to parse %s=%s, ignoring assignment: %m", lvalue, rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_use_domains = d;
+ network->dhcp_use_domains_set = true;
+ break;
+ case AF_INET6:
+ network->dhcp6_use_domains = d;
+ network->dhcp6_use_domains_set = true;
+ break;
+ case AF_UNSPEC:
+ /* For backward compatibility. */
+ if (!network->dhcp_use_domains_set)
+ network->dhcp_use_domains = d;
+ if (!network->dhcp6_use_domains_set)
+ network->dhcp6_use_domains = d;
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+
+int config_parse_dhcp_use_ntp(
+ const char* unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_UNSPEC, AF_INET, AF_INET6));
+ assert(rvalue);
+ assert(data);
+
+ r = parse_boolean(rvalue);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse UseNTP=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_use_ntp = r;
+ network->dhcp_use_ntp_set = true;
+ break;
+ case AF_INET6:
+ network->dhcp6_use_ntp = r;
+ network->dhcp6_use_ntp_set = true;
+ break;
+ case AF_UNSPEC:
+ /* For backward compatibility. */
+ if (!network->dhcp_use_ntp_set)
+ network->dhcp_use_ntp = r;
+ if (!network->dhcp6_use_ntp_set)
+ network->dhcp6_use_ntp = r;
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+
+int config_parse_dhcp_or_ra_route_table(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ uint32_t rt;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(IN_SET(ltype, AF_INET, AF_INET6));
+ assert(rvalue);
+
+ r = manager_get_route_table_from_string(network->manager, rvalue, &rt);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse RouteTable=%s, ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ switch (ltype) {
+ case AF_INET:
+ network->dhcp_route_table = rt;
+ network->dhcp_route_table_set = true;
+ break;
+ case AF_INET6:
+ network->ipv6_accept_ra_route_table = rt;
+ network->ipv6_accept_ra_route_table_set = true;
+ break;
+ default:
+ assert_not_reached();
+ }
+
+ return 0;
+}
+
+int config_parse_iaid(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ uint32_t iaid;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(IN_SET(ltype, AF_INET, AF_INET6));
+
+ r = safe_atou32(rvalue, &iaid);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Unable to read IAID, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+
+ if (ltype == AF_INET) {
+ network->dhcp_iaid = iaid;
+ network->dhcp_iaid_set = true;
+ if (!network->dhcp6_iaid_set_explicitly) {
+ /* Backward compatibility. Previously, IAID is shared by DHCPv4 and DHCPv6.
+ * If DHCPv6 IAID is not specified explicitly, then use DHCPv4 IAID for DHCPv6. */
+ network->dhcp6_iaid = iaid;
+ network->dhcp6_iaid_set = true;
+ }
+ } else {
+ assert(ltype == AF_INET6);
+ network->dhcp6_iaid = iaid;
+ network->dhcp6_iaid_set = true;
+ network->dhcp6_iaid_set_explicitly = true;
+ }
+
+ return 0;
+}
+
+int config_parse_dhcp_user_or_vendor_class(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ char ***l = ASSERT_PTR(data);
+ int r;
+
+ assert(lvalue);
+ assert(rvalue);
+ assert(IN_SET(ltype, AF_INET, AF_INET6));
+
+ if (isempty(rvalue)) {
+ *l = strv_free(*l);
+ return 0;
+ }
+
+ for (const char *p = rvalue;;) {
+ _cleanup_free_ char *w = NULL;
+ size_t len;
+
+ r = extract_first_word(&p, &w, NULL, EXTRACT_CUNESCAPE|EXTRACT_UNQUOTE);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to split user classes option, ignoring: %s", rvalue);
+ return 0;
+ }
+ if (r == 0)
+ return 0;
+
+ len = strlen(w);
+ if (ltype == AF_INET) {
+ if (len > UINT8_MAX || len == 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "%s length is not in the range 1…255, ignoring.", w);
+ continue;
+ }
+ } else {
+ if (len > UINT16_MAX || len == 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "%s length is not in the range 1…65535, ignoring.", w);
+ continue;
+ }
+ }
+
+ r = strv_consume(l, TAKE_PTR(w));
+ if (r < 0)
+ return log_oom();
+ }
+}
+
+int config_parse_dhcp_send_option(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ _cleanup_(sd_dhcp_option_unrefp) sd_dhcp_option *opt4 = NULL;
+ _cleanup_(sd_dhcp6_option_unrefp) sd_dhcp6_option *opt6 = NULL;
+ _unused_ _cleanup_(sd_dhcp_option_unrefp) sd_dhcp_option *old4 = NULL;
+ _unused_ _cleanup_(sd_dhcp6_option_unrefp) sd_dhcp6_option *old6 = NULL;
+ uint32_t uint32_data, enterprise_identifier = 0;
+ _cleanup_free_ char *word = NULL, *q = NULL;
+ OrderedHashmap **options = ASSERT_PTR(data);
+ uint16_t u16, uint16_data;
+ union in_addr_union addr;
+ DHCPOptionDataType type;
+ uint8_t u8, uint8_data;
+ const void *udata;
+ const char *p;
+ ssize_t sz;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+
+ if (isempty(rvalue)) {
+ *options = ordered_hashmap_free(*options);
+ return 0;
+ }
+
+ p = rvalue;
+ if (ltype == AF_INET6 && streq(lvalue, "SendVendorOption")) {
+ r = extract_first_word(&p, &word, ":", 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r <= 0 || isempty(p)) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid DHCP option, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+
+ r = safe_atou32(word, &enterprise_identifier);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCPv6 enterprise identifier data, ignoring assignment: %s", p);
+ return 0;
+ }
+ word = mfree(word);
+ }
+
+ r = extract_first_word(&p, &word, ":", 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r <= 0 || isempty(p)) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid DHCP option, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+
+ if (ltype == AF_INET6) {
+ r = safe_atou16(word, &u16);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid DHCP option, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+ if (u16 < 1 || u16 >= UINT16_MAX) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Invalid DHCP option, valid range is 1-65535, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+ } else {
+ r = safe_atou8(word, &u8);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid DHCP option, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+ if (u8 < 1 || u8 >= UINT8_MAX) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Invalid DHCP option, valid range is 1-254, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+ }
+
+ word = mfree(word);
+ r = extract_first_word(&p, &word, ":", 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r <= 0 || isempty(p)) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid DHCP option, ignoring assignment: %s", rvalue);
+ return 0;
+ }
+
+ type = dhcp_option_data_type_from_string(word);
+ if (type < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, type,
+ "Invalid DHCP option data type, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ switch (type) {
+ case DHCP_OPTION_DATA_UINT8:{
+ r = safe_atou8(p, &uint8_data);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP uint8 data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ udata = &uint8_data;
+ sz = sizeof(uint8_t);
+ break;
+ }
+ case DHCP_OPTION_DATA_UINT16:{
+ uint16_t k;
+
+ r = safe_atou16(p, &k);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP uint16 data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ uint16_data = htobe16(k);
+ udata = &uint16_data;
+ sz = sizeof(uint16_t);
+ break;
+ }
+ case DHCP_OPTION_DATA_UINT32: {
+ uint32_t k;
+
+ r = safe_atou32(p, &k);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP uint32 data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ uint32_data = htobe32(k);
+ udata = &uint32_data;
+ sz = sizeof(uint32_t);
+
+ break;
+ }
+ case DHCP_OPTION_DATA_IPV4ADDRESS: {
+ r = in_addr_from_string(AF_INET, p, &addr);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP ipv4address data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ udata = &addr.in;
+ sz = sizeof(addr.in.s_addr);
+ break;
+ }
+ case DHCP_OPTION_DATA_IPV6ADDRESS: {
+ r = in_addr_from_string(AF_INET6, p, &addr);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP ipv6address data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ udata = &addr.in6;
+ sz = sizeof(addr.in6.s6_addr);
+ break;
+ }
+ case DHCP_OPTION_DATA_STRING:
+ sz = cunescape(p, UNESCAPE_ACCEPT_NUL, &q);
+ if (sz < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, sz,
+ "Failed to decode DHCP option data, ignoring assignment: %s", p);
+ return 0;
+ }
+
+ udata = q;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (ltype == AF_INET6) {
+ r = sd_dhcp6_option_new(u16, udata, sz, enterprise_identifier, &opt6);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to store DHCP option '%s', ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ r = ordered_hashmap_ensure_allocated(options, &dhcp6_option_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ /* Overwrite existing option */
+ old6 = ordered_hashmap_get(*options, UINT_TO_PTR(u16));
+ r = ordered_hashmap_replace(*options, UINT_TO_PTR(u16), opt6);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to store DHCP option '%s', ignoring assignment: %m", rvalue);
+ return 0;
+ }
+ TAKE_PTR(opt6);
+ } else {
+ r = sd_dhcp_option_new(u8, udata, sz, &opt4);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to store DHCP option '%s', ignoring assignment: %m", rvalue);
+ return 0;
+ }
+
+ r = ordered_hashmap_ensure_allocated(options, &dhcp_option_hash_ops);
+ if (r < 0)
+ return log_oom();
+
+ /* Overwrite existing option */
+ old4 = ordered_hashmap_get(*options, UINT_TO_PTR(u8));
+ r = ordered_hashmap_replace(*options, UINT_TO_PTR(u8), opt4);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to store DHCP option '%s', ignoring assignment: %m", rvalue);
+ return 0;
+ }
+ TAKE_PTR(opt4);
+ }
+ return 0;
+}
+
+int config_parse_dhcp_request_options(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = userdata;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+ assert(data);
+
+ if (isempty(rvalue)) {
+ if (ltype == AF_INET)
+ network->dhcp_request_options = set_free(network->dhcp_request_options);
+ else
+ network->dhcp6_request_options = set_free(network->dhcp6_request_options);
+
+ return 0;
+ }
+
+ for (const char *p = rvalue;;) {
+ _cleanup_free_ char *n = NULL;
+ uint32_t i;
+
+ r = extract_first_word(&p, &n, NULL, 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DHCP request option, ignoring assignment: %s",
+ rvalue);
+ return 0;
+ }
+ if (r == 0)
+ return 0;
+
+ r = safe_atou32(n, &i);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "DHCP request option is invalid, ignoring assignment: %s", n);
+ continue;
+ }
+
+ if (i < 1 || i >= UINT8_MAX) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "DHCP request option is invalid, valid range is 1-254, ignoring assignment: %s", n);
+ continue;
+ }
+
+ r = set_ensure_put(ltype == AF_INET ? &network->dhcp_request_options : &network->dhcp6_request_options,
+ NULL, UINT32_TO_PTR(i));
+ if (r < 0)
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to store DHCP request option '%s', ignoring assignment: %m", n);
+ }
+}
+
+static const char* const dhcp_use_domains_table[_DHCP_USE_DOMAINS_MAX] = {
+ [DHCP_USE_DOMAINS_NO] = "no",
+ [DHCP_USE_DOMAINS_ROUTE] = "route",
+ [DHCP_USE_DOMAINS_YES] = "yes",
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(dhcp_use_domains, DHCPUseDomains, DHCP_USE_DOMAINS_YES);
+
+static const char * const dhcp_option_data_type_table[_DHCP_OPTION_DATA_MAX] = {
+ [DHCP_OPTION_DATA_UINT8] = "uint8",
+ [DHCP_OPTION_DATA_UINT16] = "uint16",
+ [DHCP_OPTION_DATA_UINT32] = "uint32",
+ [DHCP_OPTION_DATA_STRING] = "string",
+ [DHCP_OPTION_DATA_IPV4ADDRESS] = "ipv4address",
+ [DHCP_OPTION_DATA_IPV6ADDRESS] = "ipv6address",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(dhcp_option_data_type, DHCPOptionDataType);
+
+static const char* const duid_type_table[_DUID_TYPE_MAX] = {
+ [DUID_TYPE_LLT] = "link-layer-time",
+ [DUID_TYPE_EN] = "vendor",
+ [DUID_TYPE_LL] = "link-layer",
+ [DUID_TYPE_UUID] = "uuid",
+};
+DEFINE_PRIVATE_STRING_TABLE_LOOKUP_FROM_STRING(duid_type, DUIDType);
+
+int config_parse_duid_type(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ _cleanup_free_ char *type_string = NULL;
+ const char *p = ASSERT_PTR(rvalue);
+ bool force = ltype;
+ DUID *duid = ASSERT_PTR(data);
+ DUIDType type;
+ int r;
+
+ assert(filename);
+ assert(lvalue);
+
+ if (!force && duid->set)
+ return 0;
+
+ r = extract_first_word(&p, &type_string, ":", 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid syntax, ignoring: %s", rvalue);
+ return 0;
+ }
+ if (r == 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Failed to extract DUID type from '%s', ignoring.", rvalue);
+ return 0;
+ }
+
+ type = duid_type_from_string(type_string);
+ if (type < 0) {
+ uint16_t t;
+
+ r = safe_atou16(type_string, &t);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse DUID type '%s', ignoring.", type_string);
+ return 0;
+ }
+
+ type = t;
+ assert(type == t); /* Check if type can store uint16_t. */
+ }
+
+ if (!isempty(p)) {
+ usec_t u;
+
+ if (type != DUID_TYPE_LLT) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Invalid syntax, ignoring: %s", rvalue);
+ return 0;
+ }
+
+ r = parse_timestamp(p, &u);
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r,
+ "Failed to parse timestamp, ignoring: %s", p);
+ return 0;
+ }
+
+ duid->llt_time = u;
+ }
+
+ duid->type = type;
+ duid->set = force;
+
+ return 0;
+}
+
+int config_parse_manager_duid_type(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Manager *manager = ASSERT_PTR(userdata);
+ int r;
+
+ /* For backward compatibility. Setting both DHCPv4 and DHCPv6 DUID if they are not specified explicitly. */
+
+ r = config_parse_duid_type(unit, filename, line, section, section_line, lvalue, false, rvalue, &manager->dhcp_duid, manager);
+ if (r < 0)
+ return r;
+
+ return config_parse_duid_type(unit, filename, line, section, section_line, lvalue, false, rvalue, &manager->dhcp6_duid, manager);
+}
+
+int config_parse_network_duid_type(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ int r;
+
+ r = config_parse_duid_type(unit, filename, line, section, section_line, lvalue, true, rvalue, &network->dhcp_duid, network);
+ if (r < 0)
+ return r;
+
+ /* For backward compatibility, also set DHCPv6 DUID if not specified explicitly. */
+ return config_parse_duid_type(unit, filename, line, section, section_line, lvalue, false, rvalue, &network->dhcp6_duid, network);
+}
+
+int config_parse_duid_rawdata(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ uint8_t raw_data[MAX_DUID_DATA_LEN];
+ unsigned count = 0;
+ bool force = ltype;
+ DUID *duid = ASSERT_PTR(data);
+
+ assert(filename);
+ assert(lvalue);
+ assert(rvalue);
+
+ if (!force && duid->set)
+ return 0;
+
+ /* RawData contains DUID in format "NN:NN:NN..." */
+ for (const char *p = rvalue;;) {
+ int n1, n2, len, r;
+ uint32_t byte;
+ _cleanup_free_ char *cbyte = NULL;
+
+ r = extract_first_word(&p, &cbyte, ":", 0);
+ if (r == -ENOMEM)
+ return log_oom();
+ if (r < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, r, "Failed to read DUID, ignoring assignment: %s.", rvalue);
+ return 0;
+ }
+ if (r == 0)
+ break;
+
+ if (count >= MAX_DUID_DATA_LEN) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Max DUID length exceeded, ignoring assignment: %s.", rvalue);
+ return 0;
+ }
+
+ len = strlen(cbyte);
+ if (!IN_SET(len, 1, 2)) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Invalid length - DUID byte: %s, ignoring assignment: %s.", cbyte, rvalue);
+ return 0;
+ }
+ n1 = unhexchar(cbyte[0]);
+ if (len == 2)
+ n2 = unhexchar(cbyte[1]);
+ else
+ n2 = 0;
+
+ if (n1 < 0 || n2 < 0) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0, "Invalid DUID byte: %s. Ignoring assignment: %s.", cbyte, rvalue);
+ return 0;
+ }
+
+ byte = ((uint8_t) n1 << (4 * (len-1))) | (uint8_t) n2;
+ raw_data[count++] = byte;
+ }
+
+ assert_cc(sizeof(raw_data) == sizeof(duid->raw_data));
+ memcpy(duid->raw_data, raw_data, count);
+ duid->raw_data_len = count;
+ duid->set = force;
+
+ return 0;
+}
+
+int config_parse_manager_duid_rawdata(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Manager *manager = ASSERT_PTR(userdata);
+ int r;
+
+ /* For backward compatibility. Setting both DHCPv4 and DHCPv6 DUID if they are not specified explicitly. */
+
+ r = config_parse_duid_rawdata(unit, filename, line, section, section_line, lvalue, false, rvalue, &manager->dhcp_duid, manager);
+ if (r < 0)
+ return r;
+
+ return config_parse_duid_rawdata(unit, filename, line, section, section_line, lvalue, false, rvalue, &manager->dhcp6_duid, manager);
+}
+
+int config_parse_network_duid_rawdata(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ int r;
+
+ r = config_parse_duid_rawdata(unit, filename, line, section, section_line, lvalue, true, rvalue, &network->dhcp_duid, network);
+ if (r < 0)
+ return r;
+
+ /* For backward compatibility, also set DHCPv6 DUID if not specified explicitly. */
+ return config_parse_duid_rawdata(unit, filename, line, section, section_line, lvalue, false, rvalue, &network->dhcp6_duid, network);
+}
+
+int config_parse_uplink(
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *section,
+ unsigned section_line,
+ const char *lvalue,
+ int ltype,
+ const char *rvalue,
+ void *data,
+ void *userdata) {
+
+ Network *network = ASSERT_PTR(userdata);
+ bool accept_none = true;
+ int *index, r;
+ char **name;
+
+ assert(filename);
+ assert(section);
+ assert(lvalue);
+ assert(rvalue);
+
+ if (streq(section, "DHCPServer")) {
+ index = &network->dhcp_server_uplink_index;
+ name = &network->dhcp_server_uplink_name;
+ } else if (streq(section, "IPv6SendRA")) {
+ index = &network->router_uplink_index;
+ name = &network->router_uplink_name;
+ } else if (STR_IN_SET(section, "DHCPv6PrefixDelegation", "DHCPPrefixDelegation")) {
+ index = &network->dhcp_pd_uplink_index;
+ name = &network->dhcp_pd_uplink_name;
+ accept_none = false;
+ } else
+ assert_not_reached();
+
+ if (isempty(rvalue) || streq(rvalue, ":auto")) {
+ *index = UPLINK_INDEX_AUTO;
+ *name = mfree(*name);
+ return 0;
+ }
+
+ if (accept_none && streq(rvalue, ":none")) {
+ *index = UPLINK_INDEX_NONE;
+ *name = mfree(*name);
+ return 0;
+ }
+
+ if (!accept_none && streq(rvalue, ":self")) {
+ *index = UPLINK_INDEX_SELF;
+ *name = mfree(*name);
+ return 0;
+ }
+
+ r = parse_ifindex(rvalue);
+ if (r > 0) {
+ *index = r;
+ *name = mfree(*name);
+ return 0;
+ }
+
+ if (!ifname_valid_full(rvalue, IFNAME_VALID_ALTERNATIVE)) {
+ log_syntax(unit, LOG_WARNING, filename, line, 0,
+ "Invalid interface name in %s=, ignoring assignment: %s", lvalue, rvalue);
+ return 0;
+ }
+
+ /* The interface name will be resolved later. */
+ r = free_and_strdup_warn(name, rvalue);
+ if (r < 0)
+ return r;
+
+ /* Note, if uplink_name is set, then uplink_index will be ignored. So, the below does not mean
+ * an uplink interface will be selected automatically. */
+ *index = UPLINK_INDEX_AUTO;
+ return 0;
+}