dhcp: drop internal systemd DHCPv4 client

This is long replaced by nettools' n-dhcp4 client.
Drop it.

We still require NMDhcpSystemd for the DHCPv6 client.

Note that "[main].dhcp=systemd" now falls back to the internal client.
But this option was undocumented and internal anyway.

9 files changed, 10 insertions, 776 deletions

diff --git a/Makefile.am b/Makefile.am
index 60a171f528..7f018fe0bb 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -2333,8 +2333,6 @@ src_libnm_systemd_core_libnm_systemd_core_la_SOURCES = \
 	src/libnm-systemd-core/nm-sd-utils-core.h \
 	src/libnm-systemd-core/nm-sd.c \
 	src/libnm-systemd-core/nm-sd.h \
-	src/libnm-systemd-core/nm-sd-utils-dhcp.h \
-	src/libnm-systemd-core/nm-sd-utils-dhcp.c \
 	src/libnm-systemd-core/sd-adapt-core/condition.h \
 	src/libnm-systemd-core/sd-adapt-core/conf-parser.h \
 	src/libnm-systemd-core/sd-adapt-core/device-util.h \
diff --git a/NEWS b/NEWS
index 235edad1c0..69c62edef2 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,9 @@ subject to change and not guaranteed to be compatible with
 the later release.
 USE AT YOUR OWN RISK.  NOT RECOMMENDED FOR PRODUCTION USE!
 
+* Drop unused, internal systemd DHCPv4 client. This is long
+  replaced by nettools' n-dhcp4 implementation.
+
 =============================================
 NetworkManager-1.38
 Overview of changes since NetworkManager-1.36
diff --git a/src/core/dhcp/nm-dhcp-systemd.c b/src/core/dhcp/nm-dhcp-systemd.c
index 14a121e73e..e70bc23216 100644
--- a/src/core/dhcp/nm-dhcp-systemd.c
+++ b/src/core/dhcp/nm-dhcp-systemd.c
@@ -25,7 +25,6 @@
 #include "libnm-platform/nm-platform.h"
 #include "nm-dhcp-client-logging.h"
 #include "libnm-systemd-core/nm-sd.h"
-#include "libnm-systemd-core/nm-sd-utils-dhcp.h"
 
 /*****************************************************************************/
 
@@ -47,7 +46,6 @@ static GType nm_dhcp_systemd_get_type(void);
 /*****************************************************************************/
 
 typedef struct {
-    sd_dhcp_client  *client4;
     sd_dhcp6_client *client6;
     char            *lease_file;
 
@@ -70,675 +68,6 @@ G_DEFINE_TYPE(NMDhcpSystemd, nm_dhcp_systemd, NM_TYPE_DHCP_CLIENT)
 /*****************************************************************************/
 
 static NML3ConfigData *
-lease_to_ip4_config(NMDedupMultiIndex *multi_idx,
-                    const char        *iface,
-                    int                ifindex,
-                    sd_dhcp_lease     *lease,
-                    GError           **error)
-{
-    nm_auto_unref_l3cd_init NML3ConfigData *l3cd    = NULL;
-    gs_unref_hashtable GHashTable          *options = NULL;
-    const struct in_addr                   *addr_list;
-    char                                    addr_str[NM_UTILS_INET_ADDRSTRLEN];
-    const char                             *s;
-    nm_auto_free_gstring GString           *str              = NULL;
-    nm_auto_free sd_dhcp_route            **routes_static    = NULL;
-    nm_auto_free sd_dhcp_route            **routes_classless = NULL;
-    const char *const                      *search_domains   = NULL;
-    guint32                                 default_route_metric_offset;
-    guint16                                 mtu;
-    int                                     i;
-    int                                     num;
-    int                                     is_classless;
-    int                                     n_routes_static;
-    int                                     n_routes_classless;
-    const void                             *data;
-    gsize                                   data_len;
-    gboolean                                has_router_from_classless = FALSE;
-    const gint32                            ts      = nm_utils_get_monotonic_timestamp_sec();
-    gint64                                  ts_time = time(NULL);
-    struct in_addr                          a_address;
-    struct in_addr                          a_netmask;
-    struct in_addr                          a_next_server;
-    struct in_addr                          server_id;
-    struct in_addr                          broadcast;
-    const struct in_addr                   *a_router;
-    guint32                                 a_plen;
-    guint32                                 a_lifetime;
-    guint32                                 renewal;
-    guint32                                 rebinding;
-    gs_free nm_sd_dhcp_option              *private_options = NULL;
-
-    nm_assert(lease != NULL);
-
-    if (sd_dhcp_lease_get_address(lease, &a_address) < 0) {
-        nm_utils_error_set_literal(error,
-                                   NM_UTILS_ERROR_UNKNOWN,
-                                   "could not get address from lease");
-        return NULL;
-    }
-
-    if (sd_dhcp_lease_get_netmask(lease, &a_netmask) < 0) {
-        nm_utils_error_set_literal(error,
-                                   NM_UTILS_ERROR_UNKNOWN,
-                                   "could not get netmask from lease");
-        return NULL;
-    }
-
-    if (sd_dhcp_lease_get_lifetime(lease, &a_lifetime) < 0) {
-        nm_utils_error_set_literal(error,
-                                   NM_UTILS_ERROR_UNKNOWN,
-                                   "could not get lifetime from lease");
-        return NULL;
-    }
-
-    l3cd = nm_l3_config_data_new(multi_idx, ifindex, NM_IP_CONFIG_SOURCE_DHCP);
-
-    options = nm_dhcp_option_create_options_dict();
-
-    _nm_utils_inet4_ntop(a_address.s_addr, addr_str);
-    nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_NM_IP_ADDRESS, addr_str);
-
-    a_plen = nm_utils_ip4_netmask_to_prefix(a_netmask.s_addr);
-    nm_dhcp_option_add_option(options,
-                              AF_INET,
-                              NM_DHCP_OPTION_DHCP4_SUBNET_MASK,
-                              _nm_utils_inet4_ntop(a_netmask.s_addr, addr_str));
-
-    nm_dhcp_option_add_option_u64(options,
-                                  AF_INET,
-                                  NM_DHCP_OPTION_DHCP4_IP_ADDRESS_LEASE_TIME,
-                                  a_lifetime);
-    nm_dhcp_option_add_option_u64(options,
-                                  AF_INET,
-                                  NM_DHCP_OPTION_DHCP4_NM_EXPIRY,
-                                  (guint64) (ts_time + a_lifetime));
-
-    if (sd_dhcp_lease_get_next_server(lease, &a_next_server) == 0) {
-        _nm_utils_inet4_ntop(a_next_server.s_addr, addr_str);
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_NM_NEXT_SERVER, addr_str);
-    }
-
-    nm_l3_config_data_add_address_4(l3cd,
-                                    &((const NMPlatformIP4Address){
-                                        .address      = a_address.s_addr,
-                                        .peer_address = a_address.s_addr,
-                                        .plen         = a_plen,
-                                        .addr_source  = NM_IP_CONFIG_SOURCE_DHCP,
-                                        .timestamp    = ts,
-                                        .lifetime     = a_lifetime,
-                                        .preferred    = a_lifetime,
-                                    }));
-
-    if (sd_dhcp_lease_get_server_identifier(lease, &server_id) >= 0) {
-        _nm_utils_inet4_ntop(server_id.s_addr, addr_str);
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_SERVER_ID, addr_str);
-    }
-
-    if (sd_dhcp_lease_get_broadcast(lease, &broadcast) >= 0) {
-        _nm_utils_inet4_ntop(broadcast.s_addr, addr_str);
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_BROADCAST, addr_str);
-    }
-
-    num = sd_dhcp_lease_get_dns(lease, &addr_list);
-    if (num > 0) {
-        nm_gstring_prepare(&str);
-        for (i = 0; i < num; i++) {
-            _nm_utils_inet4_ntop(addr_list[i].s_addr, addr_str);
-            g_string_append(nm_gstring_add_space_delimiter(str), addr_str);
-
-            if (addr_list[i].s_addr == 0 || nm_ip4_addr_is_localhost(addr_list[i].s_addr)) {
-                /* Skip localhost addresses, like also networkd does.
-                 * See https://github.com/systemd/systemd/issues/4524. */
-                continue;
-            }
-            nm_l3_config_data_add_nameserver(l3cd, AF_INET, &addr_list[i].s_addr);
-        }
-        nm_dhcp_option_add_option(options,
-                                  AF_INET,
-                                  NM_DHCP_OPTION_DHCP4_DOMAIN_NAME_SERVER,
-                                  str->str);
-    }
-
-    num = sd_dhcp_lease_get_search_domains(lease, (char ***) &search_domains);
-    if (num > 0) {
-        nm_gstring_prepare(&str);
-        for (i = 0; i < num; i++) {
-            g_string_append(nm_gstring_add_space_delimiter(str), search_domains[i]);
-            nm_l3_config_data_add_search(l3cd, AF_INET, search_domains[i]);
-        }
-        nm_dhcp_option_add_option(options,
-                                  AF_INET,
-                                  NM_DHCP_OPTION_DHCP4_DOMAIN_SEARCH_LIST,
-                                  str->str);
-    }
-
-    if (sd_dhcp_lease_get_domainname(lease, &s) >= 0) {
-        gs_strfreev char **domains = NULL;
-        char             **d;
-
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_DOMAIN_NAME, s);
-
-        /* Multiple domains sometimes stuffed into option 15 "Domain Name".
-         * As systemd escapes such characters, split them at \\032. */
-        domains = g_strsplit(s, "\\032", 0);
-        for (d = domains; *d; d++)
-            nm_l3_config_data_add_domain(l3cd, AF_INET, *d);
-    }
-
-    if (sd_dhcp_lease_get_hostname(lease, &s) >= 0) {
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_HOST_NAME, s);
-    }
-
-    default_route_metric_offset = 0;
-    n_routes_static             = sd_dhcp_lease_get_static_routes(lease, &routes_static);
-    n_routes_classless          = sd_dhcp_lease_get_classless_routes(lease, &routes_classless);
-    for (is_classless = 1; is_classless >= 0; is_classless--) {
-        int                   n_routes = (is_classless ? n_routes_classless : n_routes_static);
-        sd_dhcp_route *const *routes   = (is_classless ? routes_classless : routes_static);
-
-        if (n_routes <= 0)
-            continue;
-
-        nm_gstring_prepare(&str);
-
-        for (i = 0; i < n_routes; i++) {
-            char           network_net_str[NM_UTILS_INET_ADDRSTRLEN];
-            char           gateway_str[NM_UTILS_INET_ADDRSTRLEN];
-            guint8         r_plen;
-            struct in_addr r_network;
-            struct in_addr r_gateway;
-            in_addr_t      network_net;
-            guint32        m;
-
-            if (sd_dhcp_route_get_destination(routes[i], &r_network) < 0)
-                continue;
-            if (sd_dhcp_route_get_destination_prefix_length(routes[i], &r_plen) < 0 || r_plen > 32)
-                continue;
-            if (sd_dhcp_route_get_gateway(routes[i], &r_gateway) < 0)
-                continue;
-
-            network_net = nm_utils_ip4_address_clear_host_address(r_network.s_addr, r_plen);
-            _nm_utils_inet4_ntop(network_net, network_net_str);
-            _nm_utils_inet4_ntop(r_gateway.s_addr, gateway_str);
-
-            g_string_append_printf(nm_gstring_add_space_delimiter(str),
-                                   "%s/%d %s",
-                                   network_net_str,
-                                   (int) r_plen,
-                                   gateway_str);
-
-            if (!is_classless && n_routes_classless > 0) {
-                /* RFC 3443: if the DHCP server returns both a Classless Static Routes
-                 * option and a Static Routes option, the DHCP client MUST ignore the
-                 * Static Routes option. */
-                continue;
-            }
-
-            if (r_plen == 0) {
-                if (!is_classless) {
-                    /* for option 33 (static route), RFC 2132 says:
-                     *
-                     * The default route (0.0.0.0) is an illegal destination for a static
-                     * route. */
-                    continue;
-                }
-
-                /* if there are multiple default routes, we add them with differing
-                 * metrics. */
-                m                         = default_route_metric_offset++;
-                has_router_from_classless = TRUE;
-            } else
-                m = 0;
-
-            nm_l3_config_data_add_route_4(l3cd,
-                                          &((const NMPlatformIP4Route){
-                                              .rt_source     = NM_IP_CONFIG_SOURCE_DHCP,
-                                              .network       = network_net,
-                                              .plen          = r_plen,
-                                              .gateway       = r_gateway.s_addr,
-                                              .pref_src      = a_address.s_addr,
-                                              .metric_any    = TRUE,
-                                              .metric        = m,
-                                              .table_any     = TRUE,
-                                              .table_coerced = 0,
-                                          }));
-        }
-
-        if (str->len > 0) {
-            nm_dhcp_option_add_option(options,
-                                      AF_INET,
-                                      is_classless ? NM_DHCP_OPTION_DHCP4_CLASSLESS_STATIC_ROUTE
-                                                   : NM_DHCP_OPTION_DHCP4_STATIC_ROUTE,
-                                      str->str);
-        }
-    }
-
-    num = sd_dhcp_lease_get_router(lease, &a_router);
-    if (num > 0) {
-        default_route_metric_offset = 0;
-
-        nm_gstring_prepare(&str);
-        for (i = 0; i < num; i++) {
-            guint32 m;
-
-            s = _nm_utils_inet4_ntop(a_router[i].s_addr, addr_str);
-            g_string_append(nm_gstring_add_space_delimiter(str), s);
-
-            if (a_router[i].s_addr == 0) {
-                /* silently skip 0.0.0.0 */
-                continue;
-            }
-
-            if (has_router_from_classless) {
-                /* If the DHCP server returns both a Classless Static Routes option and a
-                 * Router option, the DHCP client MUST ignore the Router option [RFC 3442].
-                 *
-                 * Be more lenient and ignore the Router option only if Classless Static
-                 * Routes contain a default gateway (as other DHCP backends do).
-                 */
-                continue;
-            }
-
-            /* if there are multiple default routes, we add them with differing
-             * metrics. */
-            m = default_route_metric_offset++;
-
-            nm_l3_config_data_add_route_4(l3cd,
-                                          &((const NMPlatformIP4Route){
-                                              .rt_source     = NM_IP_CONFIG_SOURCE_DHCP,
-                                              .gateway       = a_router[i].s_addr,
-                                              .pref_src      = a_address.s_addr,
-                                              .table_any     = TRUE,
-                                              .table_coerced = 0,
-                                              .metric_any    = TRUE,
-                                              .metric        = m,
-                                          }));
-        }
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_ROUTER, str->str);
-    }
-
-    if (sd_dhcp_lease_get_mtu(lease, &mtu) >= 0 && mtu) {
-        nm_dhcp_option_add_option_u64(options, AF_INET, NM_DHCP_OPTION_DHCP4_INTERFACE_MTU, mtu);
-        nm_l3_config_data_set_mtu(l3cd, mtu);
-    }
-
-    num = sd_dhcp_lease_get_ntp(lease, &addr_list);
-    if (num > 0) {
-        nm_gstring_prepare(&str);
-        for (i = 0; i < num; i++) {
-            _nm_utils_inet4_ntop(addr_list[i].s_addr, addr_str);
-            g_string_append(nm_gstring_add_space_delimiter(str), addr_str);
-        }
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_NTP_SERVER, str->str);
-    }
-
-    if (sd_dhcp_lease_get_root_path(lease, &s) >= 0) {
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_ROOT_PATH, s);
-    }
-
-    if (sd_dhcp_lease_get_t1(lease, &renewal) >= 0) {
-        nm_dhcp_option_add_option_u64(options,
-                                      AF_INET,
-                                      NM_DHCP_OPTION_DHCP4_RENEWAL_T1_TIME,
-                                      renewal);
-    }
-
-    if (sd_dhcp_lease_get_t2(lease, &rebinding) >= 0) {
-        nm_dhcp_option_add_option_u64(options,
-                                      AF_INET,
-                                      NM_DHCP_OPTION_DHCP4_REBINDING_T2_TIME,
-                                      rebinding);
-    }
-
-    if (sd_dhcp_lease_get_timezone(lease, &s) >= 0) {
-        nm_dhcp_option_add_option(options, AF_INET, NM_DHCP_OPTION_DHCP4_NEW_TZDB_TIMEZONE, s);
-    }
-
-    if (sd_dhcp_lease_get_vendor_specific(lease, &data, &data_len) >= 0) {
-        if (!!memmem(data, data_len, "ANDROID_METERED", NM_STRLEN("ANDROID_METERED")))
-            nm_l3_config_data_set_metered(l3cd, TRUE);
-    }
-
-    num = nm_sd_dhcp_lease_get_private_options(lease, &private_options);
-    if (num > 0) {
-        for (i = 0; i < num; i++) {
-            guint8        code       = private_options[i].code;
-            const guint8 *l_data     = private_options[i].data;
-            gsize         l_data_len = private_options[i].data_len;
-            char         *option_string;
-
-            if (code == NM_DHCP_OPTION_DHCP4_PRIVATE_PROXY_AUTODISCOVERY) {
-                if (nm_dhcp_lease_data_parse_cstr(l_data, l_data_len, &l_data_len)) {
-                    gs_free char *to_free = NULL;
-                    const char   *escaped;
-
-                    escaped =
-                        nm_utils_buf_utf8safe_escape((char *) l_data, l_data_len, 0, &to_free);
-                    nm_dhcp_option_add_option(options,
-                                              AF_INET,
-                                              NM_DHCP_OPTION_DHCP4_PRIVATE_PROXY_AUTODISCOVERY,
-                                              escaped ?: "");
-
-                    nm_l3_config_data_set_proxy_method(l3cd, NM_PROXY_CONFIG_METHOD_AUTO);
-                    nm_l3_config_data_set_proxy_pac_url(l3cd, escaped ?: "");
-                }
-                continue;
-            }
-            if (code == NM_DHCP_OPTION_DHCP4_PRIVATE_CLASSLESS_STATIC_ROUTE) {
-                /* nettools and dhclient parse option 249 (Microsoft Classless Static Route)
-                 * as fallback for routes and ignores them from private options.
-                 *
-                 * The systemd plugin does not, and for consistency with nettools we
-                 * also don't expose it as private option either. */
-                continue;
-            }
-
-            option_string = nm_utils_bin2hexstr_full(l_data, l_data_len, ':', FALSE, NULL);
-            nm_dhcp_option_take_option(options, AF_INET, code, option_string);
-        }
-    }
-
-    nm_dhcp_option_add_requests_to_options(options, AF_INET);
-
-    nm_l3_config_data_set_dhcp_lease_from_options(l3cd, AF_INET, g_steal_pointer(&options));
-
-    return g_steal_pointer(&l3cd);
-}
-
-/*****************************************************************************/
-
-static void
-bound4_handle(NMDhcpSystemd *self, gboolean extended)
-{
-    NMDhcpSystemdPrivate                   *priv  = NM_DHCP_SYSTEMD_GET_PRIVATE(self);
-    const char                             *iface = nm_dhcp_client_get_iface(NM_DHCP_CLIENT(self));
-    nm_auto_unref_l3cd_init NML3ConfigData *l3cd  = NULL;
-    sd_dhcp_lease                          *lease = NULL;
-    GError                                 *error = NULL;
-
-    if (sd_dhcp_client_get_lease(priv->client4, &lease) < 0 || !lease) {
-        _LOGW("no lease!");
-        nm_dhcp_client_set_state(NM_DHCP_CLIENT(self), NM_DHCP_STATE_FAIL, NULL);
-        return;
-    }
-
-    _LOGD("lease available");
-
-    l3cd = lease_to_ip4_config(nm_dhcp_client_get_multi_idx(NM_DHCP_CLIENT(self)),
-                               iface,
-                               nm_dhcp_client_get_ifindex(NM_DHCP_CLIENT(self)),
-                               lease,
-                               &error);
-    if (!l3cd) {
-        _LOGW("%s", error->message);
-        g_clear_error(&error);
-        nm_dhcp_client_set_state(NM_DHCP_CLIENT(self), NM_DHCP_STATE_FAIL, NULL);
-        return;
-    }
-
-    dhcp_lease_save(lease, priv->lease_file);
-
-    nm_dhcp_client_set_state(NM_DHCP_CLIENT(self),
-                             extended ? NM_DHCP_STATE_EXTENDED : NM_DHCP_STATE_BOUND,
-                             l3cd);
-}
-
-static int
-dhcp_event_cb(sd_dhcp_client *client, int event, gpointer user_data)
-{
-    NMDhcpSystemd        *self = NM_DHCP_SYSTEMD(user_data);
-    NMDhcpSystemdPrivate *priv = NM_DHCP_SYSTEMD_GET_PRIVATE(self);
-    char                  addr_str[INET_ADDRSTRLEN];
-    sd_dhcp_lease        *lease = NULL;
-    struct in_addr        addr;
-    int                   r;
-
-    nm_assert(priv->client4 == client);
-
-    _LOGD("client event %d", event);
-
-    switch (event) {
-    case SD_DHCP_CLIENT_EVENT_EXPIRED:
-        nm_dhcp_client_set_state(NM_DHCP_CLIENT(user_data), NM_DHCP_STATE_EXPIRE, NULL);
-        break;
-    case SD_DHCP_CLIENT_EVENT_STOP:
-        nm_dhcp_client_set_state(NM_DHCP_CLIENT(user_data), NM_DHCP_STATE_FAIL, NULL);
-        break;
-    case SD_DHCP_CLIENT_EVENT_RENEW:
-    case SD_DHCP_CLIENT_EVENT_IP_CHANGE:
-        bound4_handle(self, TRUE);
-        break;
-    case SD_DHCP_CLIENT_EVENT_IP_ACQUIRE:
-        bound4_handle(self, FALSE);
-        break;
-    case SD_DHCP_CLIENT_EVENT_SELECTING:
-        r = sd_dhcp_client_get_lease(priv->client4, &lease);
-        if (r < 0)
-            return r;
-        r = sd_dhcp_lease_get_server_identifier(lease, &addr);
-        if (r < 0)
-            return r;
-        if (nm_dhcp_client_server_id_is_rejected(NM_DHCP_CLIENT(user_data), &addr)) {
-            _LOGD("server-id %s is in the reject-list, ignoring",
-                  nm_utils_inet_ntop(AF_INET, &addr, addr_str));
-            return -ENOMSG;
-        }
-        break;
-    case SD_DHCP_CLIENT_EVENT_TRANSIENT_FAILURE:
-        break;
-    default:
-        _LOGW("unhandled DHCP event %d", event);
-        break;
-    }
-
-    return 0;
-}
-
-static gboolean
-ip4_start(NMDhcpClient *client, GError **error)
-{
-    nm_auto(sd_dhcp_client_unrefp) sd_dhcp_client *sd_client = NULL;
-    NMDhcpSystemd                                 *self      = NM_DHCP_SYSTEMD(client);
-    NMDhcpSystemdPrivate                          *priv      = NM_DHCP_SYSTEMD_GET_PRIVATE(self);
-    const NMDhcpClientConfig                      *client_config;
-    gs_free char                                  *lease_file = NULL;
-    GBytes                                        *hwaddr;
-    const uint8_t                                 *hwaddr_arr;
-    gsize                                          hwaddr_len;
-    int                                            arp_type;
-    GBytes                                        *client_id;
-    gs_unref_bytes GBytes                         *client_id_new = NULL;
-    GBytes                                        *vendor_class_identifier;
-    const uint8_t                                 *client_id_arr;
-    size_t                                         client_id_len;
-    struct in_addr                                 last_addr = {0};
-    const char                                    *hostname;
-    const char                                    *mud_url;
-    int                                            r, i;
-    GBytes                                        *bcast_hwaddr;
-    const uint8_t                                 *bcast_hwaddr_arr;
-    gsize                                          bcast_hwaddr_len;
-
-    g_return_val_if_fail(!priv->client4, FALSE);
-    g_return_val_if_fail(!priv->client6, FALSE);
-
-    client_config = nm_dhcp_client_get_config(client);
-
-    /* TODO: honor nm_dhcp_client_get_anycast_address() */
-
-    r = sd_dhcp_client_new(&sd_client, FALSE);
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to create dhcp-client: %s");
-        return FALSE;
-    }
-
-    _LOGT("dhcp-client4: set " NM_HASH_OBFUSCATE_PTR_FMT, NM_HASH_OBFUSCATE_PTR(sd_client));
-
-    r = sd_dhcp_client_attach_event(sd_client, NULL, 0);
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to attach event: %s");
-        return FALSE;
-    }
-
-    hwaddr = client_config->hwaddr;
-    if (!hwaddr || !(hwaddr_arr = g_bytes_get_data(hwaddr, &hwaddr_len))
-        || (arp_type = nm_utils_arp_type_detect_from_hwaddrlen(hwaddr_len)) < 0) {
-        nm_utils_error_set_literal(error, NM_UTILS_ERROR_UNKNOWN, "invalid MAC address");
-        return FALSE;
-    }
-
-    bcast_hwaddr_arr = NULL;
-    bcast_hwaddr     = client_config->bcast_hwaddr;
-    if (bcast_hwaddr) {
-        bcast_hwaddr_arr = g_bytes_get_data(bcast_hwaddr, &bcast_hwaddr_len);
-        if (bcast_hwaddr_len != hwaddr_len)
-            bcast_hwaddr_arr = NULL;
-    }
-
-    r = sd_dhcp_client_set_mac(sd_client,
-                               hwaddr_arr,
-                               bcast_hwaddr_arr,
-                               hwaddr_len,
-                               (guint16) arp_type);
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to set MAC address: %s");
-        return FALSE;
-    }
-
-    r = sd_dhcp_client_set_ifindex(sd_client, nm_dhcp_client_get_ifindex(client));
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to set ifindex: %s");
-        return FALSE;
-    }
-
-    nm_dhcp_utils_get_leasefile_path(AF_INET,
-                                     "internal",
-                                     client_config->iface,
-                                     client_config->uuid,
-                                     &lease_file);
-
-    if (client_config->v4.last_address)
-        inet_pton(AF_INET, client_config->v4.last_address, &last_addr);
-    else {
-        nm_auto(sd_dhcp_lease_unrefp) sd_dhcp_lease *lease = NULL;
-
-        dhcp_lease_load(&lease, lease_file);
-        if (lease)
-            sd_dhcp_lease_get_address(lease, &last_addr);
-    }
-
-    r = sd_dhcp_client_set_request_broadcast(sd_client, client_config->v4.request_broadcast);
-    nm_assert(r >= 0);
-
-    if (last_addr.s_addr) {
-        r = sd_dhcp_client_set_request_address(sd_client, &last_addr);
-        if (r < 0) {
-            nm_utils_error_set_errno(error, r, "failed to set last IPv4 address: %s");
-            return FALSE;
-        }
-    }
-
-    client_id = client_config->client_id;
-    if (!client_id) {
-        client_id_new = nm_utils_dhcp_client_id_mac(arp_type, hwaddr_arr, hwaddr_len);
-        client_id     = client_id_new;
-    }
-
-    if (!(client_id_arr = g_bytes_get_data(client_id, &client_id_len)) || client_id_len < 2) {
-        /* invalid client-ids are not expected. */
-        nm_assert_not_reached();
-
-        nm_utils_error_set_literal(error, NM_UTILS_ERROR_UNKNOWN, "no valid IPv4 client-id");
-        return FALSE;
-    }
-
-    /* Note that we always set a client-id. In particular for infiniband that is necessary,
-     * see https://tools.ietf.org/html/rfc4390#section-2.1 . */
-    r = sd_dhcp_client_set_client_id(sd_client,
-                                     client_id_arr[0],
-                                     client_id_arr + 1,
-                                     NM_MIN(client_id_len - 1, _NM_MAX_CLIENT_ID_LEN));
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to set IPv4 client-id: %s");
-        return FALSE;
-    }
-
-    /* Add requested options */
-    for (i = 0; i < (int) G_N_ELEMENTS(_nm_dhcp_option_dhcp4_options); i++) {
-        if (_nm_dhcp_option_dhcp4_options[i].include) {
-            nm_assert(_nm_dhcp_option_dhcp4_options[i].option_num <= 255);
-            r = sd_dhcp_client_set_request_option(sd_client,
-                                                  _nm_dhcp_option_dhcp4_options[i].option_num);
-            nm_assert(r >= 0 || r == -EEXIST);
-        }
-    }
-
-    hostname = client_config->hostname;
-    if (hostname) {
-        /* FIXME: sd-dhcp decides which hostname/FQDN option to send (12 or 81)
-         * only based on whether the hostname has a domain part or not. At the
-         * moment there is no way to force one or another.
-         */
-        r = sd_dhcp_client_set_hostname(sd_client, hostname);
-        if (r < 0) {
-            nm_utils_error_set_errno(error, r, "failed to set DHCP hostname: %s");
-            return FALSE;
-        }
-    }
-
-    mud_url = client_config->mud_url;
-    if (mud_url) {
-        r = sd_dhcp_client_set_mud_url(sd_client, mud_url);
-        if (r < 0) {
-            nm_utils_error_set_errno(error, r, "failed to set DHCP MUDURL: %s");
-            return FALSE;
-        }
-    }
-
-    vendor_class_identifier = client_config->vendor_class_identifier;
-    if (vendor_class_identifier) {
-        const char *option_data;
-        gsize       len;
-
-        option_data = g_bytes_get_data(vendor_class_identifier, &len);
-        nm_assert(option_data);
-        nm_assert(len <= 255);
-
-        option_data = nm_strndup_a(300, option_data, len, NULL);
-
-        r = sd_dhcp_client_set_vendor_class_identifier(sd_client, option_data);
-        if (r < 0) {
-            nm_utils_error_set_errno(error, r, "failed to set DHCP vendor class identifier: %s");
-            return FALSE;
-        }
-    }
-
-    r = sd_dhcp_client_set_callback(sd_client, dhcp_event_cb, client);
-    if (r < 0) {
-        nm_utils_error_set_errno(error, r, "failed to set callback: %s");
-        return FALSE;
-    }
-
-    priv->client4 = g_steal_pointer(&sd_client);
-
-    g_free(priv->lease_file);
-    priv->lease_file = g_steal_pointer(&lease_file);
-
-    nm_dhcp_client_set_effective_client_id(client, client_id);
-
-    r = sd_dhcp_client_start(priv->client4);
-    if (r < 0) {
-        sd_dhcp_client_set_callback(priv->client4, NULL, NULL);
-        nm_clear_pointer(&priv->client4, sd_dhcp_client_unref);
-        nm_utils_error_set_errno(error, r, "failed to start DHCP client: %s");
-        return FALSE;
-    }
-
-    return TRUE;
-}
-
-static NML3ConfigData *
 lease_to_ip6_config(NMDedupMultiIndex *multi_idx,
                     const char        *iface,
                     int                ifindex,
@@ -945,7 +274,6 @@ ip6_start(NMDhcpClient *client, const struct in6_addr *ll_addr, GError **error)
     GBytes                                          *duid;
     gboolean                                         prefix_delegation;
 
-    g_return_val_if_fail(!priv->client4, FALSE);
     g_return_val_if_fail(!priv->client6, FALSE);
 
     client_config = nm_dhcp_client_get_config(client);
@@ -1073,18 +401,13 @@ stop(NMDhcpClient *client, gboolean release)
 
     NM_DHCP_CLIENT_CLASS(nm_dhcp_systemd_parent_class)->stop(client, release);
 
-    _LOGT("dhcp-client%d: stop %p",
-          priv->client4 ? '4' : '6',
-          priv->client4 ? (gpointer) priv->client4 : (gpointer) priv->client6);
+    _LOGT("dhcp-client6: stop");
 
-    if (priv->client4) {
-        sd_dhcp_client_set_callback(priv->client4, NULL, NULL);
-        r = sd_dhcp_client_stop(priv->client4);
-    } else if (priv->client6) {
-        sd_dhcp6_client_set_callback(priv->client6, NULL, NULL);
-        r = sd_dhcp6_client_stop(priv->client6);
-    }
+    if (!priv->client6)
+        return;
 
+    sd_dhcp6_client_set_callback(priv->client6, NULL, NULL);
+    r = sd_dhcp6_client_stop(priv->client6);
     if (r)
         _LOGW("failed to stop client (%d)", r);
 }
@@ -1102,12 +425,6 @@ dispose(GObject *object)
 
     nm_clear_g_free(&priv->lease_file);
 
-    if (priv->client4) {
-        sd_dhcp_client_stop(priv->client4);
-        sd_dhcp_client_unref(priv->client4);
-        priv->client4 = NULL;
-    }
-
     if (priv->client6) {
         sd_dhcp6_client_stop(priv->client6);
         sd_dhcp6_client_unref(priv->client6);
@@ -1125,14 +442,13 @@ nm_dhcp_systemd_class_init(NMDhcpSystemdClass *sdhcp_class)
 
     object_class->dispose = dispose;
 
-    client_class->ip4_start = ip4_start;
     client_class->ip6_start = ip6_start;
     client_class->stop      = stop;
 }
 
 const NMDhcpClientFactory _nm_dhcp_client_factory_systemd = {
     .name         = "systemd",
-    .get_type_4   = nm_dhcp_systemd_get_type,
+    .get_type_4   = nm_dhcp_nettools_get_type,
     .get_type_6   = nm_dhcp_systemd_get_type,
     .undocumented = TRUE,
 };
diff --git a/src/core/tests/test-systemd.c b/src/core/tests/test-systemd.c
index 71a6a60df1..9c12032087 100644
--- a/src/core/tests/test-systemd.c
+++ b/src/core/tests/test-systemd.c
@@ -13,27 +13,6 @@
 /*****************************************************************************/
 
 static void
-test_dhcp_create(void)
-{
-    sd_dhcp_client *client4 = NULL;
-    int             r;
-
-    r = sd_dhcp_client_new(&client4, FALSE);
-    g_assert(r == 0);
-    g_assert(client4);
-
-    if (/* never true */ client4 == (gpointer) &r) {
-        /* we don't want to call this, but ensure that the linker
-         * includes all these symbols. */
-        sd_dhcp_client_start(client4);
-    }
-
-    sd_dhcp_client_unref(client4);
-}
-
-/*****************************************************************************/
-
-static void
 test_lldp_create(void)
 {
     sd_lldp_rx *lldp = NULL;
@@ -261,7 +240,6 @@ main(int argc, char **argv)
 {
     nmtst_init(&argc, &argv, TRUE);
 
-    g_test_add_func("/systemd/dhcp/create", test_dhcp_create);
     g_test_add_func("/systemd/lldp/create", test_lldp_create);
     g_test_add_func("/systemd/sd-event", test_sd_event);
     g_test_add_func("/systemd/test_path_equal", test_path_equal);
diff --git a/src/libnm-systemd-core/meson.build b/src/libnm-systemd-core/meson.build
index 80b95c4224..c2bf27e5ce 100644
--- a/src/libnm-systemd-core/meson.build
+++ b/src/libnm-systemd-core/meson.build
@@ -26,7 +26,6 @@ libnm_systemd_core = static_library(
     'src/libsystemd/sd-id128/sd-id128.c',
     'nm-sd.c',
     'nm-sd-utils-core.c',
-    'nm-sd-utils-dhcp.c',
     'sd-adapt-core/nm-sd-adapt-core.c',
   ),
   include_directories: [
diff --git a/src/libnm-systemd-core/nm-sd-utils-dhcp.c b/src/libnm-systemd-core/nm-sd-utils-dhcp.c
deleted file mode 100644
index 13c75055ec..0000000000
--- a/src/libnm-systemd-core/nm-sd-utils-dhcp.c
+++ /dev/null
@@ -1,40 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-/*
- * Copyright (C) 2019 Red Hat, Inc.
- */
-
-#include "libnm-systemd-core/nm-default-systemd-core.h"
-
-#include "nm-sd-utils-dhcp.h"
-
-#include "sd-adapt-core/nm-sd-adapt-core.h"
-#include "src/libsystemd-network/dhcp-lease-internal.h"
-
-int
-nm_sd_dhcp_lease_get_private_options(sd_dhcp_lease *lease, nm_sd_dhcp_option **out_options)
-{
-    int cnt = 0;
-
-    g_return_val_if_fail(lease, -EINVAL);
-    g_return_val_if_fail(out_options, -EINVAL);
-    g_return_val_if_fail(*out_options == NULL, -EINVAL);
-
-    if (lease->private_options == NULL)
-        return -ENODATA;
-
-    LIST_FOREACH(options, raw_option, lease->private_options)
-    cnt++;
-
-    *out_options = g_new(nm_sd_dhcp_option, cnt);
-    cnt          = 0;
-
-    LIST_FOREACH(options, raw_option, lease->private_options)
-    {
-        (*out_options)[cnt].code     = raw_option->tag;
-        (*out_options)[cnt].data     = raw_option->data;
-        (*out_options)[cnt].data_len = raw_option->length;
-        cnt++;
-    }
-
-    return cnt;
-}
diff --git a/src/libnm-systemd-core/nm-sd-utils-dhcp.h b/src/libnm-systemd-core/nm-sd-utils-dhcp.h
deleted file mode 100644
index 6487a90dfe..0000000000
--- a/src/libnm-systemd-core/nm-sd-utils-dhcp.h
+++ /dev/null
@@ -1,19 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-/*
- * Copyright (C) 2019 Red Hat, Inc.
- */
-
-#ifndef __NETWORKMANAGER_DHCP_SYSTEMD_UTILS_H__
-#define __NETWORKMANAGER_DHCP_SYSTEMD_UTILS_H__
-
-#include "nm-sd.h"
-
-typedef struct {
-    uint8_t code;
-    uint8_t data_len;
-    void   *data;
-} nm_sd_dhcp_option;
-
-int nm_sd_dhcp_lease_get_private_options(sd_dhcp_lease *lease, nm_sd_dhcp_option **out_options);
-
-#endif /* __NETWORKMANAGER_DHCP_SYSTEMD_UTILS_H__ */
diff --git a/src/libnm-systemd-core/nm-sd.c b/src/libnm-systemd-core/nm-sd.c
index 9978a159c4..b512e3fcba 100644
--- a/src/libnm-systemd-core/nm-sd.c
+++ b/src/libnm-systemd-core/nm-sd.c
@@ -108,6 +108,5 @@ nm_sd_event_attach_default(void)
 /* ensure that defines in nm-sd.h correspond to the internal defines. */
 
 #include "nm-sd-adapt-core.h"
-#include "dhcp-lease-internal.h"
 
 /*****************************************************************************/
diff --git a/src/libnm-systemd-core/nm-sd.h b/src/libnm-systemd-core/nm-sd.h
index 421f53729b..de035a841e 100644
--- a/src/libnm-systemd-core/nm-sd.h
+++ b/src/libnm-systemd-core/nm-sd.h
@@ -6,7 +6,7 @@
 #ifndef __NM_SD_H__
 #define __NM_SD_H__
 
-#include "src/systemd/sd-dhcp-client.h"
+#include "src/systemd/sd-dhcp-lease.h"
 #include "src/systemd/sd-dhcp6-client.h"
 #include "src/systemd/sd-lldp-rx.h"