sd-dhcp6-client: bind to link-local address

This ensures that several DHCPv6 clients can run on separate interfaces
simultaneously.

3 files changed, 14 insertions, 9 deletions

diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index c0562e5788..1ce1f4d8d6 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -347,9 +347,9 @@ int address_update(Address *address, unsigned char flags, unsigned char scope, s
                         link_check_ready(address->link);
 
                         if (address->family == AF_INET6 &&
-                            in_addr_is_link_local(AF_INET6, &address->in_addr) &&
-                            !address->link->ipv6ll_address) {
-                                r = link_ipv6ll_gained(address->link);
+                            in_addr_is_link_local(AF_INET6, &address->in_addr) > 0 &&
+                            in_addr_is_null(AF_INET6, (const union in_addr_union*) &address->link->ipv6ll_address) > 0) {
+                                r = link_ipv6ll_gained(address->link, &address->in_addr.in6);
                                 if (r < 0)
                                         return r;
                         }
diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index ba64473cd3..01d5942ce5 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -615,7 +615,7 @@ void link_check_ready(Link *link) {
                         return;
 
         if (link_ipv6ll_enabled(link))
-                if (!link->ipv6ll_address)
+                if (in_addr_is_null(AF_INET6, (const union in_addr_union*) &link->ipv6ll_address) > 0)
                         return;
 
         if ((link_dhcp4_enabled(link) && !link_dhcp6_enabled(link) &&
@@ -1260,9 +1260,14 @@ static int link_acquire_ipv6_conf(Link *link) {
 
         if (link_dhcp6_enabled(link)) {
                 assert(link->dhcp6_client);
+                assert(in_addr_is_link_local(AF_INET6, (const union in_addr_union*)&link->ipv6ll_address) > 0);
 
                 log_link_debug(link, "Acquiring DHCPv6 lease");
 
+                r = sd_dhcp6_client_set_local_address(link->dhcp6_client, &link->ipv6ll_address);
+                if (r < 0 && r != -EBUSY)
+                        return log_link_warning_errno(link, r, "Could not set IPv6LL address in DHCP client: %m");
+
                 r = sd_dhcp6_client_start(link->dhcp6_client);
                 if (r < 0 && r != -EBUSY)
                         return log_link_warning_errno(link, r,  "Could not acquire DHCPv6 lease: %m");
@@ -2122,7 +2127,7 @@ static int link_configure(Link *link) {
                 if (r < 0)
                         return r;
 
-                if (link->ipv6ll_address) {
+                if (in_addr_is_null(AF_INET6, (const union in_addr_union*) &link->ipv6ll_address) == 0) {
                         r = link_acquire_ipv6_conf(link);
                         if (r < 0)
                                 return r;
@@ -2473,14 +2478,14 @@ failed:
         return r;
 }
 
-int link_ipv6ll_gained(Link *link) {
+int link_ipv6ll_gained(Link *link, const struct in6_addr *address) {
         int r;
 
         assert(link);
 
         log_link_info(link, "Gained IPv6LL");
 
-        link->ipv6ll_address = true;
+        link->ipv6ll_address = *address;
         link_check_ready(link);
 
         if (!IN_SET(link->state, LINK_STATE_PENDING, LINK_STATE_PENDING, LINK_STATE_UNMANAGED, LINK_STATE_FAILED)) {
diff --git a/src/network/networkd-link.h b/src/network/networkd-link.h
index b564bcbca0..aa2235b11d 100644
--- a/src/network/networkd-link.h
+++ b/src/network/networkd-link.h
@@ -69,6 +69,7 @@ struct Link {
         char *ifname;
         char *state_file;
         struct ether_addr mac;
+        struct in6_addr ipv6ll_address;
         uint32_t mtu;
         struct udev_device *udev_device;
 
@@ -101,7 +102,6 @@ struct Link {
         sd_ipv4ll *ipv4ll;
         bool ipv4ll_address:1;
         bool ipv4ll_route:1;
-        bool ipv6ll_address:1;
 
         bool static_configured;
 
@@ -144,7 +144,7 @@ int link_save(Link *link);
 int link_carrier_reset(Link *link);
 bool link_has_carrier(Link *link);
 
-int link_ipv6ll_gained(Link *link);
+int link_ipv6ll_gained(Link *link, const struct in6_addr *address);
 
 int link_set_mtu(Link *link, uint32_t mtu);
 int link_set_hostname(Link *link, const char *hostname);