Merge pull request #15466 from elmarco/dhcp-leases

networkctl: print DHCP leases

src/basic/macro.h

@@ -448,6 +448,8 @@ static inline int __coverity_check_and_return__(int condition) {
 
 #define char_array_0(x) x[sizeof(x)-1] = 0;
 
+#define sizeof_field(struct_type, member) sizeof(((struct_type *) 0)->member)
+
 /* Returns the number of chars needed to format variables of the
  * specified type as a decimal string. Adds in extra space for a
  * negative '-' prefix (hence works correctly on signed

src/libsystemd-network/dhcp-server-internal.h

@@ -68,6 +68,9 @@ struct sd_dhcp_server {
         DHCPLease invalid_lease;
 
         uint32_t max_lease_time, default_lease_time;
+
+        sd_dhcp_server_callback_t callback;
+        void *callback_userdata;
 };
 
 typedef struct DHCPRequest {

src/libsystemd-network/sd-dhcp-client.c

@@ -27,6 +27,7 @@
 #include "random-util.h"
 #include "string-util.h"
 #include "strv.h"
+#include "utf8.h"
 #include "web-util.h"
 
 #define MAX_CLIENT_ID_LEN (sizeof(uint32_t) + MAX_DUID_LEN)  /* Arbitrary limit */
@@ -35,6 +36,32 @@
 #define RESTART_AFTER_NAK_MIN_USEC (1 * USEC_PER_SEC)
 #define RESTART_AFTER_NAK_MAX_USEC (30 * USEC_PER_MINUTE)
 
+typedef struct sd_dhcp_client_id {
+        uint8_t type;
+        union {
+                struct {
+                        /* 0: Generic (non-LL) (RFC 2132) */
+                        uint8_t data[MAX_CLIENT_ID_LEN];
+                } _packed_ gen;
+                struct {
+                        /* 1: Ethernet Link-Layer (RFC 2132) */
+                        uint8_t haddr[ETH_ALEN];
+                } _packed_ eth;
+                struct {
+                        /* 2 - 254: ARP/Link-Layer (RFC 2132) */
+                        uint8_t haddr[0];
+                } _packed_ ll;
+                struct {
+                        /* 255: Node-specific (RFC 4361) */
+                        be32_t iaid;
+                        struct duid duid;
+                } _packed_ ns;
+                struct {
+                        uint8_t data[MAX_CLIENT_ID_LEN];
+                } _packed_ raw;
+        };
+} _packed_ sd_dhcp_client_id;
+
 struct sd_dhcp_client {
         unsigned n_ref;
 
@@ -56,31 +83,7 @@ struct sd_dhcp_client {
         uint8_t mac_addr[MAX_MAC_ADDR_LEN];
         size_t mac_addr_len;
         uint16_t arp_type;
-        struct {
-                uint8_t type;
-                union {
-                        struct {
-                                /* 0: Generic (non-LL) (RFC 2132) */
-                                uint8_t data[MAX_CLIENT_ID_LEN];
-                        } _packed_ gen;
-                        struct {
-                                /* 1: Ethernet Link-Layer (RFC 2132) */
-                                uint8_t haddr[ETH_ALEN];
-                        } _packed_ eth;
-                        struct {
-                                /* 2 - 254: ARP/Link-Layer (RFC 2132) */
-                                uint8_t haddr[0];
-                        } _packed_ ll;
-                        struct {
-                                /* 255: Node-specific (RFC 4361) */
-                                be32_t iaid;
-                                struct duid duid;
-                        } _packed_ ns;
-                        struct {
-                                uint8_t data[MAX_CLIENT_ID_LEN];
-                        } _packed_ raw;
-                };
-        } _packed_ client_id;
+        sd_dhcp_client_id client_id;
         size_t client_id_len;
         char *hostname;
         char *vendor_class_identifier;
@@ -151,6 +154,60 @@ static int client_receive_message_udp(
                 void *userdata);
 static void client_stop(sd_dhcp_client *client, int error);
 
+int sd_dhcp_client_id_to_string(const void *data, size_t len, char **ret) {
+        const sd_dhcp_client_id *client_id = data;
+        _cleanup_free_ char *t = NULL;
+        int r = 0;
+
+        assert_return(data, -EINVAL);
+        assert_return(len >= 1, -EINVAL);
+        assert_return(ret, -EINVAL);
+
+        len -= 1;
+        if (len > MAX_CLIENT_ID_LEN)
+                return -EINVAL;
+
+        switch (client_id->type) {
+        case 0:
+                if (utf8_is_printable((char *) client_id->gen.data, len))
+                        r = asprintf(&t, "%.*s", (int) len, client_id->gen.data);
+                else
+                        r = asprintf(&t, "DATA");
+                break;
+        case 1:
+                if (len != sizeof_field(sd_dhcp_client_id, eth))
+                        return -EINVAL;
+
+                r = asprintf(&t, "%x:%x:%x:%x:%x:%x",
+                             client_id->eth.haddr[0],
+                             client_id->eth.haddr[1],
+                             client_id->eth.haddr[2],
+                             client_id->eth.haddr[3],
+                             client_id->eth.haddr[4],
+                             client_id->eth.haddr[5]);
+                break;
+        case 2 ... 254:
+                r = asprintf(&t, "ARP/LL");
+                break;
+        case 255:
+                if (len < 6)
+                        return -EINVAL;
+
+                uint32_t iaid = be32toh(client_id->ns.iaid);
+                uint16_t duid_type = be16toh(client_id->ns.duid.type);
+                if (dhcp_validate_duid_len(duid_type, len - 6, true) < 0)
+                        return -EINVAL;
+
+                r = asprintf(&t, "IAID:0x%x/DUID", iaid);
+                break;
+        }
+
+        if (r < 0)
+                return -ENOMEM;
+        *ret = TAKE_PTR(t);
+        return 0;
+}
+
 int sd_dhcp_client_set_callback(
                 sd_dhcp_client *client,
                 sd_dhcp_client_callback_t cb,

src/libsystemd-network/sd-dhcp-server.c

@@ -98,6 +98,9 @@ int sd_dhcp_server_configure_pool(
 
                 /* Drop any leases associated with the old address range */
                 hashmap_clear(server->leases_by_client_id);
+
+                if (server->callback)
+                        server->callback(server, SD_DHCP_SERVER_EVENT_LEASE_CHANGED, server->callback_userdata);
         }
 
         return 0;
@@ -899,6 +902,9 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
                                 hashmap_put(server->leases_by_client_id,
                                             &lease->client_id, lease);
 
+                                if (server->callback)
+                                        server->callback(server, SD_DHCP_SERVER_EVENT_LEASE_CHANGED, server->callback_userdata);
+
                                 return DHCP_ACK;
                         }
 
@@ -935,6 +941,9 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message,
                         server->bound_leases[pool_offset] = NULL;
                         hashmap_remove(server->leases_by_client_id, existing_lease);
                         dhcp_lease_free(existing_lease);
+
+                        if (server->callback)
+                                server->callback(server, SD_DHCP_SERVER_EVENT_LEASE_CHANGED, server->callback_userdata);
                 }
 
                 return 0;
@@ -1202,3 +1211,12 @@ int sd_dhcp_server_add_vendor_option(sd_dhcp_server *server, sd_dhcp_option *v)
 
         return 1;
 }
+
+int sd_dhcp_server_set_callback(sd_dhcp_server *server, sd_dhcp_server_callback_t cb, void *userdata) {
+        assert_return(server, -EINVAL);
+
+        server->callback = cb;
+        server->callback_userdata = userdata;
+
+        return 0;
+}

src/network/meson.build

@@ -61,6 +61,8 @@ sources = files('''
         networkd-conf.h
         networkd-dhcp-common.c
         networkd-dhcp-common.h
+        networkd-dhcp-server-bus.c
+        networkd-dhcp-server-bus.h
         networkd-dhcp-server.c
         networkd-dhcp-server.h
         networkd-dhcp4.c

src/network/networkctl.c

@@ -12,6 +12,7 @@
 
 #include "sd-bus.h"
 #include "sd-device.h"
+#include "sd-dhcp-client.h"
 #include "sd-hwdb.h"
 #include "sd-lldp.h"
 #include "sd-netlink.h"
@@ -471,9 +472,13 @@ static int decode_link(sd_netlink_message *m, LinkInfo *info, char **patterns, b
         return 1;
 }
 
-static int acquire_link_bitrates(sd_bus *bus, LinkInfo *link) {
-        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
-        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+static int link_get_property(
+                sd_bus *bus,
+                const LinkInfo *link,
+                sd_bus_error *error,
+                sd_bus_message **reply,
+                const char *iface,
+                const char *propname) {
         _cleanup_free_ char *path = NULL, *ifindex_str = NULL;
         int r;
 
@@ -484,17 +489,25 @@ static int acquire_link_bitrates(sd_bus *bus, LinkInfo *link) {
         if (r < 0)
                 return r;
 
-        r = sd_bus_call_method(
+        return sd_bus_call_method(
                         bus,
                         "org.freedesktop.network1",
                         path,
                         "org.freedesktop.DBus.Properties",
                         "Get",
-                        &error,
-                        &reply,
+                        error,
+                        reply,
                         "ss",
-                        "org.freedesktop.network1.Link",
-                        "BitRates");
+                        iface,
+                        propname);
+}
+
+static int acquire_link_bitrates(sd_bus *bus, LinkInfo *link) {
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        int r;
+
+        r = link_get_property(bus, link, &error, &reply, "org.freedesktop.network1.Link", "BitRates");
         if (r < 0) {
                 bool quiet = sd_bus_error_has_name(&error, SD_BUS_ERROR_UNKNOWN_PROPERTY) ||
                              sd_bus_error_has_name(&error, BUS_ERROR_SPEED_METER_INACTIVE);
@@ -1150,6 +1163,96 @@ static int dump_lldp_neighbors(Table *table, const char *prefix, int ifindex) {
         return dump_list(table, prefix, buf);
 }
 
+static int dump_dhcp_leases(Table *table, const char *prefix, sd_bus *bus, const LinkInfo *link) {
+        _cleanup_strv_free_ char **buf = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        int r;
+
+        r = link_get_property(bus, link, &error, &reply, "org.freedesktop.network1.DHCPServer", "Leases");
+        if (r < 0) {
+                bool quiet = sd_bus_error_has_name(&error, SD_BUS_ERROR_UNKNOWN_PROPERTY);
+
+                log_full_errno(quiet ? LOG_DEBUG : LOG_WARNING,
+                               r, "Failed to query link DHCP leases: %s", bus_error_message(&error, r));
+                return 0;
+        }
+
+        r = sd_bus_message_enter_container(reply, 'v', "a(uayayayayt)");
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_message_enter_container(reply, 'a', "(uayayayayt)");
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        while ((r = sd_bus_message_enter_container(reply, 'r', "uayayayayt")) > 0) {
+                _cleanup_free_ char *id = NULL, *ip = NULL;
+                const void *client_id, *addr, *gtw, *hwaddr;
+                size_t client_id_sz, sz;
+                uint64_t expiration;
+                uint32_t family;
+
+                r = sd_bus_message_read(reply, "u", &family);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_array(reply, 'y', &client_id, &client_id_sz);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_array(reply, 'y', &addr, &sz);
+                if (r < 0 || sz != 4)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_array(reply, 'y', &gtw, &sz);
+                if (r < 0 || sz != 4)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_array(reply, 'y', &hwaddr, &sz);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_bus_message_read_basic(reply, 't', &expiration);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = sd_dhcp_client_id_to_string(client_id, client_id_sz, &id);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = in_addr_to_string(family, addr, &ip);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+
+                r = strv_extendf(&buf, "%s (to %s)", ip, id);
+                if (r < 0)
+                        return log_oom();
+
+                r = sd_bus_message_exit_container(reply);
+                if (r < 0)
+                        return bus_log_parse_error(r);
+        }
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_message_exit_container(reply);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        r = sd_bus_message_exit_container(reply);
+        if (r < 0)
+                return bus_log_parse_error(r);
+
+        if (strv_isempty(buf)) {
+                r = strv_extendf(&buf, "none");
+                if (r < 0)
+                        return log_oom();
+        }
+
+        return dump_list(table, prefix, buf);
+}
+
 static int dump_ifindexes(Table *table, const char *prefix, const int *ifindexes) {
         unsigned c;
         int r;
@@ -1270,6 +1373,7 @@ static int show_logs(const LinkInfo *info) {
 }
 
 static int link_status_one(
+                sd_bus *bus,
                 sd_netlink *rtnl,
                 sd_hwdb *hwdb,
                 const LinkInfo *info) {
@@ -1973,6 +2077,10 @@ static int link_status_one(
         if (r < 0)
                 return r;
 
+        r = dump_dhcp_leases(table, "Offered DHCP leases:", bus, info);
+        if (r < 0)
+                return r;
+
         r = dump_statistics(table, info);
         if (r < 0)
                 return r;
@@ -2090,7 +2198,7 @@ static int link_status(int argc, char *argv[], void *userdata) {
                 if (i > 0)
                         fputc('\n', stdout);
 
-                link_status_one(rtnl, hwdb, links + i);
+                link_status_one(bus, rtnl, hwdb, links + i);
         }
 
         return 0;

src/network/networkd-dhcp-server-bus.c

@@ -0,0 +1,111 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "sd-dhcp-server.h"
+
+#include "alloc-util.h"
+#include "bus-common-errors.h"
+#include "bus-util.h"
+#include "dhcp-server-internal.h"
+#include "networkd-dhcp-server-bus.h"
+#include "networkd-link-bus.h"
+#include "networkd-manager.h"
+#include "strv.h"
+
+static int property_get_leases(
+                sd_bus *bus,
+                const char *path,
+                const char *interface,
+                const char *property,
+                sd_bus_message *reply,
+                void *userdata,
+                sd_bus_error *error) {
+        Link *l = userdata;
+        sd_dhcp_server *s;
+        DHCPLease *lease;
+        Iterator i;
+        int r;
+
+        assert(reply);
+        assert(l);
+
+        s = l->dhcp_server;
+        if (!s)
+                return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "Link %s has no DHCP server.", l->ifname);
+
+        r = sd_bus_message_open_container(reply, 'a', "(uayayayayt)");
+        if (r < 0)
+                return r;
+
+        HASHMAP_FOREACH(lease, s->leases_by_client_id, i) {
+                r = sd_bus_message_open_container(reply, 'r', "uayayayayt");
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append(reply, "u", (uint32_t)AF_INET);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_array(reply, 'y', lease->client_id.data, lease->client_id.length);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_array(reply, 'y', &lease->address, sizeof(lease->address));
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_array(reply, 'y', &lease->gateway, sizeof(lease->gateway));
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_array(reply, 'y', &lease->chaddr, sizeof(lease->chaddr));
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_basic(reply, 't', &lease->expiration);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_close_container(reply);
+                if (r < 0)
+                        return r;
+        }
+
+        return sd_bus_message_close_container(reply);
+}
+
+static int dhcp_server_emit_changed(Link *link, const char *property, ...) {
+        _cleanup_free_ char *path = NULL;
+        char **l;
+
+        assert(link);
+
+        path = link_bus_path(link);
+        if (!path)
+                return log_oom();
+
+        l = strv_from_stdarg_alloca(property);
+
+        return sd_bus_emit_properties_changed_strv(
+                        link->manager->bus,
+                        path,
+                        "org.freedesktop.network1.DHCPServer",
+                        l);
+}
+
+void dhcp_server_callback(sd_dhcp_server *s, uint64_t event, void *data) {
+        Link *l = data;
+
+        assert(l);
+
+        if (event & SD_DHCP_SERVER_EVENT_LEASE_CHANGED)
+                (void) dhcp_server_emit_changed(l, "Leases", NULL);
+}
+
+
+const sd_bus_vtable dhcp_server_vtable[] = {
+        SD_BUS_VTABLE_START(0),
+
+        SD_BUS_PROPERTY("Leases", "a(uayayayayt)", property_get_leases, 0, SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+
+        SD_BUS_VTABLE_END
+};

src/network/networkd-dhcp-server-bus.h

@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include "sd-bus.h"
+#include "networkd-link.h"
+
+extern const sd_bus_vtable dhcp_server_vtable[];
+
+void dhcp_server_callback(sd_dhcp_server *server, uint64_t event, void *data);

src/network/networkd-link-bus.c

@@ -760,6 +760,9 @@ int link_object_find(sd_bus *bus, const char *path, const char *interface, void
         if (r < 0)
                 return 0;
 
+        if (streq(interface, "org.freedesktop.network1.DHCPServer") && !link->dhcp_server)
+                return 0;
+
         *found = link;
 
         return 1;

src/network/networkd-manager.c

@@ -24,6 +24,7 @@
 #include "local-addresses.h"
 #include "netlink-util.h"
 #include "network-internal.h"
+#include "networkd-dhcp-server-bus.h"
 #include "networkd-dhcp6.h"
 #include "networkd-link-bus.h"
 #include "networkd-manager-bus.h"
@@ -154,6 +155,10 @@ int manager_connect_bus(Manager *m) {
         if (r < 0)
                return log_error_errno(r, "Failed to add link object vtable: %m");
 
+        r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/network1/link", "org.freedesktop.network1.DHCPServer", dhcp_server_vtable, link_object_find, m);
+        if (r < 0)
+               return log_error_errno(r, "Failed to add link object vtable: %m");
+
         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/network1/link", link_node_enumerator, m);
         if (r < 0)
                 return log_error_errno(r, "Failed to add link enumerator: %m");

src/systemd/sd-dhcp-client.h

@@ -205,6 +205,8 @@ sd_dhcp_client *sd_dhcp_client_unref(sd_dhcp_client *client);
  * options when using RFC7844 Anonymity Profiles */
 int sd_dhcp_client_new(sd_dhcp_client **ret, int anonymize);
 
+int sd_dhcp_client_id_to_string(const void *data, size_t len, char **ret);
+
 int sd_dhcp_client_attach_event(
                 sd_dhcp_client *client,
                 sd_event *event,

src/systemd/sd-dhcp-server.h

@@ -31,6 +31,10 @@ _SD_BEGIN_DECLARATIONS;
 
 typedef struct sd_dhcp_server sd_dhcp_server;
 
+enum {
+        SD_DHCP_SERVER_EVENT_LEASE_CHANGED                      = 1 << 0,
+};
+
 int sd_dhcp_server_new(sd_dhcp_server **ret, int ifindex);
 
 sd_dhcp_server *sd_dhcp_server_ref(sd_dhcp_server *server);
@@ -40,6 +44,10 @@ int sd_dhcp_server_attach_event(sd_dhcp_server *client, sd_event *event, int64_t
 int sd_dhcp_server_detach_event(sd_dhcp_server *client);
 sd_event *sd_dhcp_server_get_event(sd_dhcp_server *client);
 
+typedef void (*sd_dhcp_server_callback_t)(sd_dhcp_server *server, uint64_t event, void *userdata);
+
+int sd_dhcp_server_set_callback(sd_dhcp_server *server, sd_dhcp_server_callback_t cb, void *userdata);
+
 int sd_dhcp_server_is_running(sd_dhcp_server *server);
 
 int sd_dhcp_server_start(sd_dhcp_server *server);