networkd: Add DHCPv6 as a configuration option to radv prefixes

The Network section IPv6PrefixDelegation= option takes two new
configuration values, namely "static" and "dhcpv6" in addition
to boolean yes and no values. Static prefixes in IPv6Prefix
sections are used when IPv6PrefixDelegation= option contains
"static", and DHCPv6 is queried for prefixes when the option
contains "dhcpv6". Both DHCPv6 and static prefixes are used when
the option contains a boolean true value. The default value is
false as before, meaning no prefixes are delegated.

5 files changed, 56 insertions, 7 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 60ac980ad9..8e1f0fe819 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -129,7 +129,7 @@ static bool link_radv_enabled(Link *link) {
         if (!link_ipv6ll_enabled(link))
                 return false;
 
-        return link->network->router_prefix_delegation;
+        return (link->network->router_prefix_delegation != RADV_PREFIX_DELEGATION_NONE);
 }
 
 static bool link_lldp_rx_enabled(Link *link) {
diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf
index e1990b0302..816dbaf709 100644
--- a/src/network/networkd-network-gperf.gperf
+++ b/src/network/networkd-network-gperf.gperf
@@ -156,7 +156,7 @@ BridgeFDB.VLANId,                       config_parse_fdb_vlan_id,
 BridgeVLAN.PVID,                        config_parse_brvlan_pvid,                       0,                             0
 BridgeVLAN.VLAN,                        config_parse_brvlan_vlan,                       0,                             0
 BridgeVLAN.EgressUntagged,              config_parse_brvlan_untagged,                   0,                             0
-Network.IPv6PrefixDelegation,           config_parse_bool,                              0,                             offsetof(Network, router_prefix_delegation)
+Network.IPv6PrefixDelegation,           config_parse_router_prefix_delegation,          0,                             0
 IPv6PrefixDelegation.RouterLifetimeSec, config_parse_sec,                               0,                             offsetof(Network, router_lifetime_usec)
 IPv6PrefixDelegation.Managed,           config_parse_bool,                              0,                             offsetof(Network, router_managed)
 IPv6PrefixDelegation.OtherInformation,  config_parse_bool,                              0,                             offsetof(Network, router_other_information)
diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h
index c45f0f72f5..ad56fc5f68 100644
--- a/src/network/networkd-network.h
+++ b/src/network/networkd-network.h
@@ -86,6 +86,13 @@ typedef struct DUID {
         uint8_t raw_data[MAX_DUID_LEN];
 } DUID;
 
+typedef enum RADVPrefixDelegation {
+        RADV_PREFIX_DELEGATION_NONE,
+        RADV_PREFIX_DELEGATION_STATIC,
+        RADV_PREFIX_DELEGATION_DHCP6,
+        RADV_PREFIX_DELEGATION_BOTH,
+} RADVPrefixDelegation;
+
 typedef struct NetworkConfigSection {
         unsigned line;
         char filename[];
@@ -165,7 +172,7 @@ struct Network {
         bool ipv4ll_route;
 
         /* IPv6 prefix delegation support */
-        bool router_prefix_delegation;
+        RADVPrefixDelegation router_prefix_delegation;
         usec_t router_lifetime_usec;
         uint8_t router_preference;
         bool router_managed;
diff --git a/src/network/networkd-radv.c b/src/network/networkd-radv.c
index c72acc9b82..a7e66f575b 100644
--- a/src/network/networkd-radv.c
+++ b/src/network/networkd-radv.c
@@ -28,6 +28,43 @@
 #include "sd-radv.h"
 #include "string-util.h"
 
+int config_parse_router_prefix_delegation(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 d;
+
+        assert(filename);
+        assert(section);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        if (streq(rvalue, "static"))
+                network->router_prefix_delegation = RADV_PREFIX_DELEGATION_STATIC;
+        else if (streq(rvalue, "dhcpv6"))
+                network->router_prefix_delegation = RADV_PREFIX_DELEGATION_DHCP6;
+        else {
+                d = parse_boolean(rvalue);
+                if (d > 0)
+                        network->router_prefix_delegation = RADV_PREFIX_DELEGATION_BOTH;
+                else
+                        network->router_prefix_delegation = RADV_PREFIX_DELEGATION_NONE;
+
+                if (d < 0)
+                        log_syntax(unit, LOG_ERR, filename, line, -EINVAL, "Router prefix delegation '%s' is invalid, ignoring assignment: %m", rvalue);
+        }
+
+        return 0;
+}
+
 int config_parse_router_preference(const char *unit,
                                    const char *filename,
                                    unsigned line,
@@ -461,10 +498,14 @@ int radv_configure(Link *link) {
                         return r;
         }
 
-        LIST_FOREACH(prefixes, p, link->network->static_prefixes) {
-                r = sd_radv_add_prefix(link->radv, p->radv_prefix);
-                if (r != -EEXIST && r < 0)
-                        return r;
+        if (IN_SET(link->network->router_prefix_delegation,
+                   RADV_PREFIX_DELEGATION_STATIC,
+                   RADV_PREFIX_DELEGATION_BOTH)) {
+                LIST_FOREACH(prefixes, p, link->network->static_prefixes) {
+                        r = sd_radv_add_prefix(link->radv, p->radv_prefix);
+                        if (r != -EEXIST && r < 0)
+                                return r;
+                }
         }
 
         return radv_emit_dns(link);
diff --git a/src/network/networkd-radv.h b/src/network/networkd-radv.h
index a31a9f0e15..22a169d263 100644
--- a/src/network/networkd-radv.h
+++ b/src/network/networkd-radv.h
@@ -42,6 +42,7 @@ int prefix_new_static(Network *network, const char *filename, unsigned section,
 DEFINE_TRIVIAL_CLEANUP_FUNC(Prefix*, prefix_free);
 #define _cleanup_prefix_free_ _cleanup_(prefix_freep)
 
+int config_parse_router_prefix_delegation(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_router_preference(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_prefix(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_prefix_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);