[dhcpv6] Add basic support for stateful and stateless DHCPv6

Add support for the stateful and stateless variants of the DHCPv6
protocol.  The resulting settings block is registered as
"net<x>.dhcpv6", and DHCPv6 options can be obtained using
e.g. "${net0.dhcpv6/23:ipv6}" to obtain the IPv6 DNS server address.

IPv6 addresses obtained via stateful DHCPv6 are not yet applied to the
network device.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

2 files changed, 216 insertions, 0 deletions

diff --git a/src/include/ipxe/dhcpv6.h b/src/include/ipxe/dhcpv6.h
new file mode 100644
index 00000000..7a1a2b07
--- /dev/null
+++ b/src/include/ipxe/dhcpv6.h
@@ -0,0 +1,215 @@
+#ifndef _IPXE_DHCPV6_H
+#define _IPXE_DHCPV6_H
+
+/** @file
+ *
+ * Dynamic Host Configuration Protocol for IPv6
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <ipxe/in.h>
+
+/** DHCPv6 server port */
+#define DHCPV6_SERVER_PORT 547
+
+/** DHCPv6 client port */
+#define DHCPV6_CLIENT_PORT 546
+
+/**
+ * A DHCPv6 option
+ *
+ */
+struct dhcpv6_option {
+	/** Code */
+	uint16_t code;
+	/** Length of the data field */
+	uint16_t len;
+	/** Data */
+	uint8_t data[0];
+} __attribute__ (( packed ));
+
+/** DHCP unique identifier based on link-layer address (DUID-LL) */
+struct dhcpv6_duid_ll {
+	/** Type */
+	uint16_t type;
+	/** Hardware type */
+	uint16_t htype;
+	/** Link-layer address */
+	uint8_t ll_addr[0];
+} __attribute__ (( packed ));
+
+/** DHCP unique identifier based on link-layer address (DUID-LL) */
+#define DHCPV6_DUID_LL 3
+
+/** DHCPv6 client or server identifier option */
+struct dhcpv6_duid_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** DHCP unique identifier (DUID) */
+	uint8_t duid[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 client identifier option */
+#define DHCPV6_CLIENT_ID 1
+
+/** DHCPv6 server identifier option */
+#define DHCPV6_SERVER_ID 2
+
+/** DHCPv6 identity association for non-temporary address (IA_NA) option */
+struct dhcpv6_ia_na_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** Identity association identifier (IAID) */
+	uint32_t iaid;
+	/** Renew time (in seconds) */
+	uint32_t renew;
+	/** Rebind time (in seconds) */
+	uint32_t rebind;
+	/** IA_NA options */
+	struct dhcpv6_option options[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 identity association for non-temporary address (IA_NA) option */
+#define DHCPV6_IA_NA 3
+
+/** DHCPv6 identity association address (IAADDR) option */
+struct dhcpv6_iaaddr_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** IPv6 address */
+	struct in6_addr address;
+	/** Preferred lifetime (in seconds) */
+	uint32_t preferred;
+	/** Valid lifetime (in seconds) */
+	uint32_t valid;
+	/** IAADDR options */
+	struct dhcpv6_option options[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 identity association address (IAADDR) option */
+#define DHCPV6_IAADDR 5
+
+/** DHCPv6 option request option */
+struct dhcpv6_option_request_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** Requested options */
+	uint16_t requested[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 option request option */
+#define DHCPV6_OPTION_REQUEST 6
+
+/** DHCPv6 elapsed time option */
+struct dhcpv6_elapsed_time_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** Elapsed time, in centiseconds */
+	uint16_t elapsed;
+} __attribute__ (( packed ));
+
+/** DHCPv6 elapsed time option */
+#define DHCPV6_ELAPSED_TIME 8
+
+/** DHCPv6 status code option */
+struct dhcpv6_status_code_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** Status code */
+	uint16_t status;
+	/** Status message */
+	char message[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 status code option */
+#define DHCPV6_STATUS_CODE 13
+
+/** DHCPv6 user class */
+struct dhcpv6_user_class {
+	/** Length */
+	uint16_t len;
+	/** User class string */
+	char string[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 user class option */
+struct dhcpv6_user_class_option {
+	/** Option header */
+	struct dhcpv6_option header;
+	/** User class */
+	struct dhcpv6_user_class user_class[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 user class option */
+#define DHCPV6_USER_CLASS 15
+
+/** DHCPv6 DNS recursive name server option */
+#define DHCPV6_DNS_SERVER 23
+
+/** DHCPv6 domain search list option */
+#define DHCPV6_DOMAIN_SEARCH 24
+
+/**
+ * Any DHCPv6 option
+ *
+ */
+union dhcpv6_any_option {
+	struct dhcpv6_option header;
+	struct dhcpv6_duid_option duid;
+	struct dhcpv6_ia_na_option ia_na;
+	struct dhcpv6_iaaddr_option iaaddr;
+	struct dhcpv6_option_request_option option_request;
+	struct dhcpv6_elapsed_time_option elapsed_time;
+	struct dhcpv6_status_code_option status_code;
+	struct dhcpv6_user_class_option user_class;
+};
+
+/**
+ * A DHCPv6 header
+ *
+ */
+struct dhcpv6_header {
+	/** Message type */
+	uint8_t type;
+	/** Transaction ID */
+	uint8_t xid[3];
+	/** Options */
+	struct dhcpv6_option options[0];
+} __attribute__ (( packed ));
+
+/** DHCPv6 solicitation */
+#define DHCPV6_SOLICIT 1
+
+/** DHCPv6 advertisement */
+#define DHCPV6_ADVERTISE 2
+
+/** DHCPv6 request */
+#define DHCPV6_REQUEST 3
+
+/** DHCPv6 reply */
+#define DHCPV6_REPLY 7
+
+/** DHCPv6 information request */
+#define DHCPV6_INFORMATION_REQUEST 11
+
+/** DHCPv6 settings block name */
+#define DHCPV6_SETTINGS_NAME "dhcpv6"
+
+/**
+ * Construct all-DHCP-relay-agents-and-servers multicast address
+ *
+ * @v addr		Zeroed address to construct
+ */
+static inline void ipv6_all_dhcp_relay_and_servers ( struct in6_addr *addr ) {
+	addr->s6_addr16[0] = htons ( 0xff02 );
+	addr->s6_addr[13] = 1;
+	addr->s6_addr[15] = 2;
+}
+
+extern int start_dhcpv6 ( struct interface *job, struct net_device *netdev,
+			  int stateful );
+
+#endif /* _IPXE_DHCPV6_H */
diff --git a/src/include/ipxe/errfile.h b/src/include/ipxe/errfile.h
index 1db94466..8e5e30f0 100644
--- a/src/include/ipxe/errfile.h
+++ b/src/include/ipxe/errfile.h
@@ -219,6 +219,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #define ERRFILE_socket			( ERRFILE_NET | 0x00380000 )
 #define ERRFILE_icmp			( ERRFILE_NET | 0x00390000 )
 #define ERRFILE_ping			( ERRFILE_NET | 0x003a0000 )
+#define ERRFILE_dhcpv6			( ERRFILE_NET | 0x003b0000 )
 
 #define ERRFILE_image		      ( ERRFILE_IMAGE | 0x00000000 )
 #define ERRFILE_elf		      ( ERRFILE_IMAGE | 0x00010000 )