sd-dhcp6-client: Add functions to bind to DHCPv6 UDP socket

Add a function that creates a UDP socket bound to the given interface
and optionally to an IPv6 address. Add another function that will
send the DHCPv6 UDP packet to its destination.

Using IPV6_PKTINFO in setsockopt to bind the IPv6 socket to an
interface is documented in section 4. of RFC 3542, "Advanced Sockets
Application Program Interface (API) for IPv6"

Add a define for DHCPv6 Relay Agents and Servers multicast address as
its not available elsewhere.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/libsystemd-network/dhcp6-internal.h b/src/libsystemd-network/dhcp6-internal.h
index 30b624d54c..7a491fb2e6 100644
--- a/src/libsystemd-network/dhcp6-internal.h
+++ b/src/libsystemd-network/dhcp6-internal.h
@@ -65,3 +65,7 @@ int dhcp6_option_append(uint8_t **buf, size_t *buflen, uint16_t code,
 int dhcp6_option_append_ia(uint8_t **buf, size_t *buflen, DHCP6IA *ia);
 int dhcp6_option_parse(uint8_t **buf, size_t *buflen, uint16_t *optcode,
                        size_t *optlen, uint8_t **optvalue);
+
+int dhcp6_network_bind_udp_socket(int index, struct in6_addr *address);
+int dhcp6_network_send_udp_socket(int s, struct in6_addr *address,
+                                  const void *packet, size_t len);