networkd: address add support to configure flags (#4201)

This patch enables to configure

IFA_F_HOMEADDRESS
IFA_F_NODAD
IFA_F_MANAGETEMPADDR
IFA_F_NOPREFIXROUTE
IFA_F_MCAUTOJOIN

5 files changed, 125 insertions, 0 deletions

diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 0af927db19..2fb4907634 100644
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -695,6 +695,57 @@
             which is then configured to use them explicitly.</para>
           </listitem>
         </varlistentry>
+        <varlistentry>
+          <term><varname>HomeAddress=</varname></term>
+          <listitem>
+            <para>Takes a boolean argument. Designates this address the "home address" as defined in
+            <ulink url="https://tools.ietf.org/html/rfc6275">RFC 6275</ulink>.
+            Supported only on IPv6. Defaults to false.</para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><varname>DuplicateAddressDetection=</varname></term>
+          <listitem>
+            <para>Takes a boolean argument. Do not perform Duplicate Address Detection
+            <ulink url="https://tools.ietf.org/html/rfc4862">RFC 4862</ulink> when adding this address.
+            Supported only on IPv6. Defaults to false.</para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><varname>ManageTemporaryAddress=</varname></term>
+          <listitem>
+            <para>Takes a boolean argument. If true the kernel manage temporary addresses created
+            from this one as template on behalf of Privacy Extensions
+            <ulink url="https://tools.ietf.org/html/rfc3041">RFC 3041</ulink>.  For this to become
+            active, the use_tempaddr sysctl setting has to be set to a value greater than zero.
+            The given address needs to have a prefix length of 64. This flag allows to use privacy
+            extensions in a manually configured network, just like if stateless auto-configuration
+            was active. Defaults to false. </para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><varname>PrefixRoute=</varname></term>
+          <listitem>
+            <para>Takes a boolean argument. When adding or modifying an IPv6 address, the userspace
+            application needs a way to suppress adding a prefix route. This is for example relevant
+            together with IFA_F_MANAGERTEMPADDR, where userspace creates autoconf generated addresses,
+            but depending on on-link, no route for the prefix should be added. Defaults to false.</para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><varname>AutoJoin=</varname></term>
+          <listitem>
+            <para>Takes a boolean argument. Joining multicast group on ethernet level via
+            <command>ip maddr</command> command would not work if we have an Ethernet switch that does
+            IGMP snooping since the switch would not replicate multicast packets on  ports that did not
+            have IGMP reports for the multicast addresses. Linux vxlan interfaces created via
+            <command>ip link add vxlan</command> or networkd's netdev kind vxlan have the group option
+            that enables then to do the required join. By extending ip address command with option
+            <literal>autojoin</literal> we can get similar functionality for openvswitch (OVS) vxlan
+            interfaces as well as other tunneling mechanisms that need to receive multicast traffic.
+            Defaults to <literal>no</literal>.</para>
+          </listitem>
+        </varlistentry>
       </variablelist>
   </refsect1>
 
diff --git a/src/basic/missing.h b/src/basic/missing.h
index 13ff51cd35..4a78269e33 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -1052,6 +1052,10 @@ typedef int32_t key_serial_t;
 #define ETHERTYPE_LLDP 0x88cc
 #endif
 
+#ifndef IFA_F_MCAUTOJOIN
+#define IFA_F_MCAUTOJOIN 0x400
+#endif
+
 #endif
 
 #include "missing_syscall.h"
diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index 5498e352d8..ed52d5e42d 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -571,6 +571,21 @@ int address_configure(
 
         address->flags |= IFA_F_PERMANENT;
 
+        if (address->home_address)
+                address->flags |= IFA_F_HOMEADDRESS;
+
+        if (address->duplicate_address_detection)
+                address->flags |= IFA_F_NODAD;
+
+        if (address->manage_temporary_address)
+                address->flags |= IFA_F_MANAGETEMPADDR;
+
+        if (address->prefix_route)
+                address->flags |= IFA_F_NOPREFIXROUTE;
+
+        if (address->autojoin)
+                address->flags |= IFA_F_MCAUTOJOIN;
+
         r = sd_rtnl_message_addr_set_flags(req, (address->flags & 0xff));
         if (r < 0)
                 return log_error_errno(r, "Could not set flags: %m");
@@ -856,6 +871,50 @@ int config_parse_lifetime(const char *unit,
         return 0;
 }
 
+int config_parse_address_flags(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;
+        _cleanup_address_free_ Address *n = NULL;
+        int r;
+
+        assert(filename);
+        assert(section);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        r = address_new_static(network, section_line, &n);
+        if (r < 0)
+                return r;
+
+        r = parse_boolean(rvalue);
+        if (r < 0) {
+                log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse address flag, ignoring: %s", rvalue);
+                return 0;
+        }
+
+        if (streq(lvalue, "HomeAddress"))
+                n->home_address = r;
+        else if (streq(lvalue, "DuplicateAddressDetection"))
+                n->duplicate_address_detection = r;
+        else if (streq(lvalue, "ManageTemporaryAddress"))
+                n->manage_temporary_address = r;
+        else if (streq(lvalue, "PrefixRoute"))
+                n->prefix_route = r;
+        else if (streq(lvalue, "AutoJoin"))
+                n->autojoin = r;
+
+        return 0;
+}
+
 bool address_is_ready(const Address *a) {
         assert(a);
 
diff --git a/src/network/networkd-address.h b/src/network/networkd-address.h
index 03c4bea7c6..bc3b4fc7f3 100644
--- a/src/network/networkd-address.h
+++ b/src/network/networkd-address.h
@@ -53,6 +53,11 @@ struct Address {
         union in_addr_union in_addr_peer;
 
         bool ip_masquerade_done:1;
+        bool duplicate_address_detection;
+        bool manage_temporary_address;
+        bool home_address;
+        bool prefix_route;
+        bool autojoin;
 
         LIST_FIELDS(Address, addresses);
 };
@@ -77,3 +82,4 @@ int config_parse_address(const char *unit, const char *filename, unsigned line,
 int config_parse_broadcast(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);
 int config_parse_label(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);
 int config_parse_lifetime(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);
+int config_parse_address_flags(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);
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index 62779c7c48..5587961b9f 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -70,6 +70,11 @@ Address.Peer,                           config_parse_address,
 Address.Broadcast,                      config_parse_broadcast,                         0,                             0
 Address.Label,                          config_parse_label,                             0,                             0
 Address.PreferredLifetime,              config_parse_lifetime,                          0,                             0
+Address.HomeAddress,                    config_parse_address_flags,                     0,                             0
+Address.DuplicateAddressDetection,      config_parse_address_flags,                     0,                             0
+Address.ManageTemporaryAddress,         config_parse_address_flags,                     0,                             0
+Address.PrefixRoute,                    config_parse_address_flags,                     0,                             0
+Address.AutoJoin,                       config_parse_address_flags,                     0,                             0
 Route.Gateway,                          config_parse_gateway,                           0,                             0
 Route.Destination,                      config_parse_destination,                       0,                             0
 Route.Source,                           config_parse_destination,                       0,                             0