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-rw-r--r--src/include/ipxe/dhcpv6.h215
-rw-r--r--src/include/ipxe/errfile.h1
-rw-r--r--src/net/ndp.c41
-rw-r--r--src/net/udp/dhcpv6.c955
4 files changed, 1207 insertions, 5 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 )
diff --git a/src/net/ndp.c b/src/net/ndp.c
index 1b1109ed..f56bbe92 100644
--- a/src/net/ndp.c
+++ b/src/net/ndp.c
@@ -29,6 +29,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#include <ipxe/ipv6.h>
#include <ipxe/icmpv6.h>
#include <ipxe/neighbour.h>
+#include <ipxe/dhcpv6.h>
#include <ipxe/ndp.h>
/** @file
@@ -596,6 +597,8 @@ struct ipv6conf {
/** Job control interface */
struct interface job;
+ /** DHCPv6 interface */
+ struct interface dhcp;
/** Network device being configured */
struct net_device *netdev;
@@ -646,6 +649,7 @@ static void ipv6conf_done ( struct ipv6conf *ipv6conf, int rc ) {
/* Shut down interfaces */
intf_shutdown ( &ipv6conf->job, rc );
+ intf_shutdown ( &ipv6conf->dhcp, rc );
/* Stop timer */
stop_timer ( &ipv6conf->timer );
@@ -686,6 +690,8 @@ static void ipv6conf_expired ( struct retry_timer *timer, int fail ) {
static int ipv6conf_rx_router_advertisement ( struct net_device *netdev,
unsigned int flags ) {
struct ipv6conf *ipv6conf;
+ int stateful;
+ int rc;
/* Identify IPv6 configurator, if any */
ipv6conf = ipv6conf_demux ( netdev );
@@ -697,13 +703,28 @@ static int ipv6conf_rx_router_advertisement ( struct net_device *netdev,
return 0;
}
- /* Fail if stateful address autoconfiguration is required */
- if ( flags & NDP_ROUTER_MANAGED ) {
- ipv6conf_done ( ipv6conf, -ENOTSUP );
- return -ENOTSUP;
+ /* If this is not the first solicited router advertisement, ignore it */
+ if ( ! timer_running ( &ipv6conf->timer ) )
+ return 0;
+
+ /* Stop router solicitation timer */
+ stop_timer ( &ipv6conf->timer );
+
+ /* Start DHCPv6 if required */
+ if ( flags & ( NDP_ROUTER_MANAGED | NDP_ROUTER_OTHER ) ) {
+ stateful = ( flags & NDP_ROUTER_MANAGED );
+ if ( ( rc = start_dhcpv6 ( &ipv6conf->dhcp, netdev,
+ stateful ) ) != 0 ) {
+ DBGC ( netdev, "NDP could not start state%s DHCPv6: "
+ "%s\n", ( stateful ? "ful" : "less" ),
+ strerror ( rc ) );
+ ipv6conf_done ( ipv6conf, rc );
+ return rc;
+ }
+ return 0;
}
- /* Mark autoconfiguration as complete */
+ /* Otherwise, terminate autoconfiguration */
ipv6conf_done ( ipv6conf, 0 );
return 0;
@@ -718,6 +739,15 @@ static struct interface_operation ipv6conf_job_op[] = {
static struct interface_descriptor ipv6conf_job_desc =
INTF_DESC ( struct ipv6conf, job, ipv6conf_job_op );
+/** IPv6 configurator DHCPv6 interface operations */
+static struct interface_operation ipv6conf_dhcp_op[] = {
+ INTF_OP ( intf_close, struct ipv6conf *, ipv6conf_done ),
+};
+
+/** IPv6 configurator DHCPv6 interface descriptor */
+static struct interface_descriptor ipv6conf_dhcp_desc =
+ INTF_DESC ( struct ipv6conf, dhcp, ipv6conf_dhcp_op );
+
/**
* Start IPv6 autoconfiguration
*
@@ -734,6 +764,7 @@ int start_ipv6conf ( struct interface *job, struct net_device *netdev ) {
return -ENOMEM;
ref_init ( &ipv6conf->refcnt, ipv6conf_free );
intf_init ( &ipv6conf->job, &ipv6conf_job_desc, &ipv6conf->refcnt );
+ intf_init ( &ipv6conf->dhcp, &ipv6conf_dhcp_desc, &ipv6conf->refcnt );
timer_init ( &ipv6conf->timer, ipv6conf_expired, &ipv6conf->refcnt );
ipv6conf->netdev = netdev_get ( netdev );
diff --git a/src/net/udp/dhcpv6.c b/src/net/udp/dhcpv6.c
new file mode 100644
index 00000000..ebd7221f
--- /dev/null
+++ b/src/net/udp/dhcpv6.c
@@ -0,0 +1,955 @@
+/*
+ * Copyright (C) 2013 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <byteswap.h>
+#include <ipxe/interface.h>
+#include <ipxe/xfer.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/open.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/settings.h>
+#include <ipxe/retry.h>
+#include <ipxe/timer.h>
+#include <ipxe/in.h>
+#include <ipxe/crc32.h>
+#include <ipxe/errortab.h>
+#include <ipxe/dhcpv6.h>
+
+/** @file
+ *
+ * Dynamic Host Configuration Protocol for IPv6
+ *
+ */
+
+/* Disambiguate the various error causes */
+#define EPROTO_UNSPECFAIL __einfo_error ( EINFO_EPROTO_UNSPECFAIL )
+#define EINFO_EPROTO_UNSPECFAIL \
+ __einfo_uniqify ( EINFO_EPROTO, 1, "Unspecified server failure" )
+#define EPROTO_NOADDRSAVAIL __einfo_error ( EINFO_EPROTO_NOADDRSAVAIL )
+#define EINFO_EPROTO_NOADDRSAVAIL \
+ __einfo_uniqify ( EINFO_EPROTO, 2, "No addresses available" )
+#define EPROTO_NOBINDING __einfo_error ( EINFO_EPROTO_NOBINDING )
+#define EINFO_EPROTO_NOBINDING \
+ __einfo_uniqify ( EINFO_EPROTO, 3, "Client record unavailable" )
+#define EPROTO_NOTONLINK __einfo_error ( EINFO_EPROTO_NOTONLINK )
+#define EINFO_EPROTO_NOTONLINK \
+ __einfo_uniqify ( EINFO_EPROTO, 4, "Prefix not on link" )
+#define EPROTO_USEMULTICAST __einfo_error ( EINFO_EPROTO_USEMULTICAST )
+#define EINFO_EPROTO_USEMULTICAST \
+ __einfo_uniqify ( EINFO_EPROTO, 5, "Use multicast address" )
+#define EPROTO_STATUS( status ) \
+ EUNIQ ( EINFO_EPROTO, ( (status) & 0x0f ), EPROTO_UNSPECFAIL, \
+ EPROTO_NOADDRSAVAIL, EPROTO_NOBINDING, \
+ EPROTO_NOTONLINK, EPROTO_USEMULTICAST )
+
+/** Human-readable error messages */
+struct errortab dhcpv6_errors[] __errortab = {
+ __einfo_errortab ( EINFO_EPROTO_NOADDRSAVAIL ),
+};
+
+/****************************************************************************
+ *
+ * DHCPv6 option lists
+ *
+ */
+
+/** A DHCPv6 option list */
+struct dhcpv6_option_list {
+ /** Data buffer */
+ const void *data;
+ /** Length of data buffer */
+ size_t len;
+};
+
+/**
+ * Find DHCPv6 option
+ *
+ * @v options DHCPv6 option list
+ * @v code Option code
+ * @ret option DHCPv6 option, or NULL if not found
+ */
+static const union dhcpv6_any_option *
+dhcpv6_option ( struct dhcpv6_option_list *options, unsigned int code ) {
+ const union dhcpv6_any_option *option = options->data;
+ size_t remaining = options->len;
+ size_t data_len;
+
+ /* Scan through list of options */
+ while ( remaining >= sizeof ( option->header ) ) {
+
+ /* Calculate and validate option length */
+ remaining -= sizeof ( option->header );
+ data_len = ntohs ( option->header.len );
+ if ( data_len > remaining ) {
+ /* Malformed option list */
+ return NULL;
+ }
+
+ /* Return if we have found the specified option */
+ if ( option->header.code == htons ( code ) )
+ return option;
+
+ /* Otherwise, move to the next option */
+ option = ( ( ( void * ) option->header.data ) + data_len );
+ remaining -= data_len;
+ }
+
+ return NULL;
+}
+
+/**
+ * Check DHCPv6 client or server identifier
+ *
+ * @v options DHCPv6 option list
+ * @v code Option code
+ * @v expected Expected value
+ * @v len Length of expected value
+ * @ret rc Return status code
+ */
+static int dhcpv6_check_duid ( struct dhcpv6_option_list *options,
+ unsigned int code, const void *expected,
+ size_t len ) {
+ const union dhcpv6_any_option *option;
+ const struct dhcpv6_duid_option *duid;
+
+ /* Find option */
+ option = dhcpv6_option ( options, code );
+ if ( ! option )
+ return -ENOENT;
+ duid = &option->duid;
+
+ /* Check option length */
+ if ( ntohs ( duid->header.len ) != len )
+ return -EINVAL;
+
+ /* Compare option value */
+ if ( memcmp ( duid->duid, expected, len ) != 0 )
+ return -EINVAL;
+
+ return 0;
+}
+
+/**
+ * Get DHCPv6 status code
+ *
+ * @v options DHCPv6 option list
+ * @ret rc Return status code
+ */
+static int dhcpv6_status_code ( struct dhcpv6_option_list *options ) {
+ const union dhcpv6_any_option *option;
+ const struct dhcpv6_status_code_option *status_code;
+ unsigned int status;
+
+ /* Find status code option, if present */
+ option = dhcpv6_option ( options, DHCPV6_STATUS_CODE );
+ if ( ! option ) {
+ /* Omitted status code should be treated as "success" */
+ return 0;
+ }
+ status_code = &option->status_code;
+
+ /* Sanity check */
+ if ( ntohs ( status_code->header.len ) <
+ ( sizeof ( *status_code ) - sizeof ( status_code->header ) ) ) {
+ return -EINVAL;
+ }
+
+ /* Calculate iPXE error code from DHCPv6 status code */
+ status = ntohs ( status_code->status );
+ return ( status ? -EPROTO_STATUS ( status ) : 0 );
+}
+
+/**
+ * Get DHCPv6 identity association address
+ *
+ * @v options DHCPv6 option list
+ * @v iaid Identity association ID
+ * @v address IPv6 address to fill in
+ * @ret rc Return status code
+ */
+static int dhcpv6_iaaddr ( struct dhcpv6_option_list *options, uint32_t iaid,
+ struct in6_addr *address ) {
+ const union dhcpv6_any_option *option;
+ const struct dhcpv6_ia_na_option *ia_na;
+ const struct dhcpv6_iaaddr_option *iaaddr;
+ struct dhcpv6_option_list suboptions;
+ size_t len;
+ int rc;
+
+ /* Find identity association option, if present */
+ option = dhcpv6_option ( options, DHCPV6_IA_NA );
+ if ( ! option )
+ return -ENOENT;
+ ia_na = &option->ia_na;
+
+ /* Sanity check */
+ len = ntohs ( ia_na->header.len );
+ if ( len < ( sizeof ( *ia_na ) - sizeof ( ia_na->header ) ) )
+ return -EINVAL;
+
+ /* Check identity association ID */
+ if ( ia_na->iaid != htonl ( iaid ) )
+ return -EINVAL;
+
+ /* Construct IA_NA sub-options list */
+ suboptions.data = ia_na->options;
+ suboptions.len = ( len + sizeof ( ia_na->header ) -
+ offsetof ( typeof ( *ia_na ), options ) );
+
+ /* Check IA_NA status code */
+ if ( ( rc = dhcpv6_status_code ( &suboptions ) ) != 0 )
+ return rc;
+
+ /* Find identity association address, if present */
+ option = dhcpv6_option ( &suboptions, DHCPV6_IAADDR );
+ if ( ! option )
+ return -ENOENT;
+ iaaddr = &option->iaaddr;
+
+ /* Sanity check */
+ len = ntohs ( iaaddr->header.len );
+ if ( len < ( sizeof ( *iaaddr ) - sizeof ( iaaddr->header ) ) )
+ return -EINVAL;
+
+ /* Construct IAADDR sub-options list */
+ suboptions.data = iaaddr->options;
+ suboptions.len = ( len + sizeof ( iaaddr->header ) -
+ offsetof ( typeof ( *iaaddr ), options ) );
+
+ /* Check IAADDR status code */
+ if ( ( rc = dhcpv6_status_code ( &suboptions ) ) != 0 )
+ return rc;
+
+ /* Extract IPv6 address */
+ memcpy ( address, &iaaddr->address, sizeof ( *address ) );
+
+ return 0;
+}
+
+/****************************************************************************
+ *
+ * DHCPv6 settings blocks
+ *
+ */
+
+/** DHCPv6 settings scope */
+static struct settings_scope dhcpv6_settings_scope;
+
+/** A DHCPv6 settings block */
+struct dhcpv6_settings {
+ /** Reference count */
+ struct refcnt refcnt;
+ /** Settings block */
+ struct settings settings;
+ /** Option list */
+ struct dhcpv6_option_list options;
+};
+
+/**
+ * Check applicability of DHCPv6 setting
+ *
+ * @v settings Settings block
+ * @v setting Setting
+ * @ret applies Setting applies within this settings block
+ */
+static int dhcpv6_applies ( struct settings *settings __unused,
+ struct setting *setting ) {
+
+ return ( setting->scope == &dhcpv6_settings_scope );
+}
+
+/**
+ * Fetch value of DHCPv6 setting
+ *
+ * @v settings Settings block
+ * @v setting Setting to fetch
+ * @v data Buffer to fill with setting data
+ * @v len Length of buffer
+ * @ret len Length of setting data, or negative error
+ */
+static int dhcpv6_fetch ( struct settings *settings,
+ struct setting *setting,
+ void *data, size_t len ) {
+ struct dhcpv6_settings *dhcpv6set =
+ container_of ( settings, struct dhcpv6_settings, settings );
+ const union dhcpv6_any_option *option;
+ size_t option_len;
+
+ /* Find option */
+ option = dhcpv6_option ( &dhcpv6set->options, setting->tag );
+ if ( ! option )
+ return -ENOENT;
+
+ /* Copy option to data buffer */
+ option_len = ntohs ( option->header.len );
+ if ( len > option_len )
+ len = option_len;
+ memcpy ( data, option->header.data, len );
+ return option_len;
+}
+
+/** DHCPv6 settings operations */
+static struct settings_operations dhcpv6_settings_operations = {
+ .applies = dhcpv6_applies,
+ .fetch = dhcpv6_fetch,
+};
+
+/**
+ * Register DHCPv6 options as network device settings
+ *
+ * @v options DHCPv6 option list
+ * @v parent Parent settings block
+ * @ret rc Return status code
+ */
+static int dhcpv6_register ( struct dhcpv6_option_list *options,
+ struct settings *parent ) {
+ struct dhcpv6_settings *dhcpv6set;
+ void *data;
+ size_t len;
+ int rc;
+
+ /* Allocate and initialise structure */
+ dhcpv6set = zalloc ( sizeof ( *dhcpv6set ) + options->len );
+ if ( ! dhcpv6set ) {
+ rc = -ENOMEM;
+ goto err_alloc;
+ }
+ ref_init ( &dhcpv6set->refcnt, NULL );
+ settings_init ( &dhcpv6set->settings, &dhcpv6_settings_operations,
+ &dhcpv6set->refcnt, &dhcpv6_settings_scope );
+ data = ( ( ( void * ) dhcpv6set ) + sizeof ( *dhcpv6set ) );
+ len = options->len;
+ memcpy ( data, options->data, len );
+ dhcpv6set->options.data = data;
+ dhcpv6set->options.len = len;
+
+ /* Register settings */
+ if ( ( rc = register_settings ( &dhcpv6set->settings, parent,
+ DHCPV6_SETTINGS_NAME ) ) != 0 )
+ goto err_register;
+
+ err_register:
+ ref_put ( &dhcpv6set->refcnt );
+ err_alloc:
+ return rc;
+}
+
+/****************************************************************************
+ *
+ * DHCPv6 protocol
+ *
+ */
+
+/** Options to be requested */
+static uint16_t dhcpv6_requested_options[] = {
+ htons ( DHCPV6_DNS_SERVER ), htons ( DHCPV6_DOMAIN_SEARCH ),
+};
+
+/**
+ * Name a DHCPv6 packet type
+ *
+ * @v type DHCPv6 packet type
+ * @ret name DHCPv6 packet type name
+ */
+static __attribute__ (( unused )) const char *
+dhcpv6_type_name ( unsigned int type ) {
+ static char buf[ 12 /* "UNKNOWN-xxx" + NUL */ ];
+
+ switch ( type ) {
+ case DHCPV6_SOLICIT: return "SOLICIT";
+ case DHCPV6_ADVERTISE: return "ADVERTISE";
+ case DHCPV6_REQUEST: return "REQUEST";
+ case DHCPV6_REPLY: return "REPLY";
+ case DHCPV6_INFORMATION_REQUEST: return "INFORMATION-REQUEST";
+ default:
+ snprintf ( buf, sizeof ( buf ), "UNKNOWN-%d", type );
+ return buf;
+ }
+}
+
+/** A DHCPv6 session state */
+struct dhcpv6_session_state {
+ /** Current transmitted packet type */
+ uint8_t tx_type;
+ /** Current expected received packet type */
+ uint8_t rx_type;
+ /** Flags */
+ uint8_t flags;
+ /** Next state (or NULL to terminate) */
+ struct dhcpv6_session_state *next;
+};
+
+/** DHCPv6 session state flags */
+enum dhcpv6_session_state_flags {
+ /** Include identity association within request */
+ DHCPV6_TX_IA_NA = 0x01,
+ /** Include leased IPv6 address within request */
+ DHCPV6_TX_IAADDR = 0x02,
+ /** Record received server ID */
+ DHCPV6_RX_SERVER_ID = 0x04,
+ /** Record received IPv6 address */
+ DHCPV6_RX_IAADDR = 0x08,
+};
+
+/** DHCPv6 request state */
+static struct dhcpv6_session_state dhcpv6_request = {
+ .tx_type = DHCPV6_REQUEST,
+ .rx_type = DHCPV6_REPLY,
+ .flags = ( DHCPV6_TX_IA_NA | DHCPV6_TX_IAADDR | DHCPV6_RX_IAADDR ),
+ .next = NULL,
+};
+
+/** DHCPv6 solicitation state */
+static struct dhcpv6_session_state dhcpv6_solicit = {
+ .tx_type = DHCPV6_SOLICIT,
+ .rx_type = DHCPV6_ADVERTISE,
+ .flags = ( DHCPV6_TX_IA_NA | DHCPV6_RX_SERVER_ID | DHCPV6_RX_IAADDR ),
+ .next = &dhcpv6_request,
+};
+
+/** DHCPv6 information request state */
+static struct dhcpv6_session_state dhcpv6_information_request = {
+ .tx_type = DHCPV6_INFORMATION_REQUEST,
+ .rx_type = DHCPV6_REPLY,
+ .flags = 0,
+ .next = NULL,
+};
+
+/** A DHCPv6 session */
+struct dhcpv6_session {
+ /** Reference counter */
+ struct refcnt refcnt;
+ /** Job control interface */
+ struct interface job;
+ /** Data transfer interface */
+ struct interface xfer;
+
+ /** Network device being configured */
+ struct net_device *netdev;
+ /** Transaction ID */
+ uint8_t xid[3];
+ /** Identity association ID */
+ uint32_t iaid;
+ /** Start time (in ticks) */
+ unsigned long start;
+ /** Client DUID */
+ void *client_duid;
+ /** Client DUID length */
+ size_t client_duid_len;
+ /** Server DUID, if known */
+ void *server_duid;
+ /** Server DUID length */
+ size_t server_duid_len;
+ /** Leased IPv6 address */
+ struct in6_addr lease;
+
+ /** Retransmission timer */
+ struct retry_timer timer;
+
+ /** Current session state */
+ struct dhcpv6_session_state *state;
+ /** Current timeout status code */
+ int rc;
+};
+
+/**
+ * Free DHCPv6 session
+ *
+ * @v refcnt Reference count
+ */
+static void dhcpv6_free ( struct refcnt *refcnt ) {
+ struct dhcpv6_session *dhcpv6 =
+ container_of ( refcnt, struct dhcpv6_session, refcnt );
+
+ netdev_put ( dhcpv6->netdev );
+ free ( dhcpv6->server_duid );
+ free ( dhcpv6 );
+}
+
+/**
+ * Terminate DHCPv6 session
+ *
+ * @v dhcpv6 DHCPv6 session
+ * @v rc Reason for close
+ */
+static void dhcpv6_finished ( struct dhcpv6_session *dhcpv6, int rc ) {
+
+ /* Stop timer */
+ stop_timer ( &dhcpv6->timer );
+
+ /* Shut down interfaces */
+ intf_shutdown ( &dhcpv6->xfer, rc );
+ intf_shutdown ( &dhcpv6->job, rc );
+}
+
+/**
+ * Transition to new DHCPv6 session state
+ *
+ * @v dhcpv6 DHCPv6 session
+ * @v state New session state
+ */
+static void dhcpv6_set_state ( struct dhcpv6_session *dhcpv6,
+ struct dhcpv6_session_state *state ) {
+
+ DBGC ( dhcpv6, "DHCPv6 %s entering %s state\n", dhcpv6->netdev->name,
+ dhcpv6_type_name ( state->tx_type ) );
+
+ /* Record state */
+ dhcpv6->state = state;
+
+ /* Default to -ETIMEDOUT if no more specific error is recorded */
+ dhcpv6->rc = -ETIMEDOUT;
+
+ /* Start timer to trigger transmission */
+ start_timer_nodelay ( &dhcpv6->timer );
+}
+
+/**
+ * Get DHCPv6 user class
+ *
+ * @v data Data buffer
+ * @v len Length of data buffer
+ * @ret len Length of user class
+ */
+static size_t dhcpv6_user_class ( void *data, size_t len ) {
+ static const char default_user_class[4] = { 'i', 'P', 'X', 'E' };
+ int actual_len;
+
+ /* Fetch user-class setting, if defined */
+ actual_len = fetch_setting ( NULL, &user_class_setting, data, len );
+ if ( actual_len >= 0 )
+ return actual_len;
+
+ /* Otherwise, use the default user class ("iPXE") */
+ if ( len > sizeof ( default_user_class ) )
+ len = sizeof ( default_user_class );
+ memcpy ( data, default_user_class, len );
+ return sizeof ( default_user_class );
+}
+
+/**
+ * Transmit current request
+ *
+ * @v dhcpv6 DHCPv6 session
+ * @ret rc Return status code
+ */
+static int dhcpv6_tx ( struct dhcpv6_session *dhcpv6 ) {
+ struct dhcpv6_duid_option *client_id;
+ struct dhcpv6_duid_option *server_id;
+ struct dhcpv6_ia_na_option *ia_na;
+ struct dhcpv6_iaaddr_option *iaaddr;
+ struct dhcpv6_option_request_option *option_request;
+ struct dhcpv6_user_class_option *user_class;
+ struct dhcpv6_elapsed_time_option *elapsed;
+ struct dhcpv6_header *dhcphdr;
+ struct io_buffer *iobuf;
+ size_t client_id_len;
+ size_t server_id_len;
+ size_t ia_na_len;
+ size_t option_request_len;
+ size_t user_class_string_len;
+ size_t user_class_len;
+ size_t elapsed_len;
+ size_t total_len;
+ int rc;
+
+ /* Calculate lengths */
+ client_id_len = ( sizeof ( *client_id ) + dhcpv6->client_duid_len );
+ server_id_len = ( dhcpv6->server_duid ? ( sizeof ( *server_id ) +
+ dhcpv6->server_duid_len ) :0);
+ if ( dhcpv6->state->flags & DHCPV6_TX_IA_NA ) {
+ ia_na_len = sizeof ( *ia_na );
+ if ( dhcpv6->state->flags & DHCPV6_TX_IAADDR )
+ ia_na_len += sizeof ( *iaaddr );
+ } else {
+ ia_na_len = 0;
+ }
+ option_request_len = ( sizeof ( *option_request ) +
+ sizeof ( dhcpv6_requested_options ) );
+ user_class_string_len = dhcpv6_user_class ( NULL, 0 );
+ user_class_len = ( sizeof ( *user_class ) +
+ sizeof ( user_class->user_class[0] ) +
+ user_class_string_len );
+ elapsed_len = sizeof ( *elapsed );
+ total_len = ( sizeof ( *dhcphdr ) + client_id_len + server_id_len +
+ ia_na_len + option_request_len + user_class_len +
+ elapsed_len );
+
+ /* Allocate packet */
+ iobuf = xfer_alloc_iob ( &dhcpv6->xfer, total_len );
+ if ( ! iobuf )
+ return -ENOMEM;
+
+ /* Construct header */
+ dhcphdr = iob_put ( iobuf, sizeof ( *dhcphdr ) );
+ dhcphdr->type = dhcpv6->state->tx_type;
+ memcpy ( dhcphdr->xid, dhcpv6->xid, sizeof ( dhcphdr->xid ) );
+
+ /* Construct client identifier */
+ client_id = iob_put ( iobuf, client_id_len );
+ client_id->header.code = htons ( DHCPV6_CLIENT_ID );
+ client_id->header.len = htons ( client_id_len -
+ sizeof ( client_id->header ) );
+ memcpy ( client_id->duid, dhcpv6->client_duid,
+ dhcpv6->client_duid_len );
+
+ /* Construct server identifier, if applicable */
+ if ( server_id_len ) {
+ server_id = iob_put ( iobuf, server_id_len );
+ server_id->header.code = htons ( DHCPV6_SERVER_ID );
+ server_id->header.len = htons ( server_id_len -
+ sizeof ( server_id->header ) );
+ memcpy ( server_id->duid, dhcpv6->server_duid,
+ dhcpv6->server_duid_len );
+ }
+
+ /* Construct identity association, if applicable */
+ if ( ia_na_len ) {
+ ia_na = iob_put ( iobuf, ia_na_len );
+ ia_na->header.code = htons ( DHCPV6_IA_NA );
+ ia_na->header.len = htons ( ia_na_len -
+ sizeof ( ia_na->header ) );
+ ia_na->iaid = htonl ( dhcpv6->iaid );
+ ia_na->renew = htonl ( 0 );
+ ia_na->rebind = htonl ( 0 );
+ if ( dhcpv6->state->flags & DHCPV6_TX_IAADDR ) {
+ iaaddr = ( ( void * ) ia_na->options );
+ iaaddr->header.code = htons ( DHCPV6_IAADDR );
+ iaaddr->header.len = htons ( sizeof ( *iaaddr ) -
+ sizeof ( iaaddr->header ));
+ memcpy ( &iaaddr->address, &dhcpv6->lease,
+ sizeof ( iaaddr->address ) );
+ iaaddr->preferred = htonl ( 0 );
+ iaaddr->valid = htonl ( 0 );
+ }
+ }
+
+ /* Construct option request */
+ option_request = iob_put ( iobuf, option_request_len );
+ option_request->header.code = htons ( DHCPV6_OPTION_REQUEST );
+ option_request->header.len = htons ( option_request_len -
+ sizeof ( option_request->header ));
+ memcpy ( option_request->requested, dhcpv6_requested_options,
+ sizeof ( dhcpv6_requested_options ) );
+
+ /* Construct user class */
+ user_class = iob_put ( iobuf, user_class_len );
+ user_class->header.code = htons ( DHCPV6_USER_CLASS );
+ user_class->header.len = htons ( user_class_len -
+ sizeof ( user_class->header ) );
+ user_class->user_class[0].len = htons ( user_class_string_len );
+ dhcpv6_user_class ( user_class->user_class[0].string,
+ user_class_string_len );
+
+ /* Construct elapsed time */
+ elapsed = iob_put ( iobuf, elapsed_len );
+ elapsed->header.code = htons ( DHCPV6_ELAPSED_TIME );
+ elapsed->header.len = htons ( elapsed_len -
+ sizeof ( elapsed->header ) );
+ elapsed->elapsed = htons ( ( ( currticks() - dhcpv6->start ) * 100 ) /
+ TICKS_PER_SEC );
+
+ /* Sanity check */
+ assert ( iob_len ( iobuf ) == total_len );
+
+ /* Transmit packet */
+ if ( ( rc = xfer_deliver_iob ( &dhcpv6->xfer, iobuf ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s could not transmit: %s\n",
+ dhcpv6->netdev->name, strerror ( rc ) );
+ return rc;
+ }
+
+ return 0;
+}
+
+/**
+ * Handle timer expiry
+ *
+ * @v timer Retransmission timer
+ * @v fail Failure indicator
+ */
+static void dhcpv6_timer_expired ( struct retry_timer *timer, int fail ) {
+ struct dhcpv6_session *dhcpv6 =
+ container_of ( timer, struct dhcpv6_session, timer );
+
+ /* If we have failed, terminate DHCPv6 */
+ if ( fail ) {
+ dhcpv6_finished ( dhcpv6, dhcpv6->rc );
+ return;
+ }
+
+ /* Restart timer */
+ start_timer ( &dhcpv6->timer );
+
+ /* (Re)transmit current request */
+ dhcpv6_tx ( dhcpv6 );
+}
+
+/**
+ * Receive new data
+ *
+ * @v dhcpv6 DHCPv6 session
+ * @v iobuf I/O buffer
+ * @v meta Data transfer metadata
+ * @ret rc Return status code
+ */
+static int dhcpv6_rx ( struct dhcpv6_session *dhcpv6,
+ struct io_buffer *iobuf,
+ struct xfer_metadata *meta ) {
+ struct settings *parent = netdev_settings ( dhcpv6->netdev );
+ struct sockaddr_in6 *src = ( ( struct sockaddr_in6 * ) meta->src );
+ struct dhcpv6_header *dhcphdr = iobuf->data;
+ struct dhcpv6_option_list options;
+ const union dhcpv6_any_option *option;
+ int rc;
+
+ /* Sanity checks */
+ if ( iob_len ( iobuf ) < sizeof ( *dhcphdr ) ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received packet too short (%zd "
+ "bytes, min %zd bytes)\n", dhcpv6->netdev->name,
+ iob_len ( iobuf ), sizeof ( *dhcphdr ) );
+ rc = -EINVAL;
+ goto done;
+ }
+ assert ( src != NULL );
+ assert ( src->sin6_family == AF_INET6 );
+ DBGC ( dhcpv6, "DHCPv6 %s received %s from %s\n",
+ dhcpv6->netdev->name, dhcpv6_type_name ( dhcphdr->type ),
+ inet6_ntoa ( &src->sin6_addr ) );
+
+ /* Construct option list */
+ options.data = dhcphdr->options;
+ options.len = ( iob_len ( iobuf ) -
+ offsetof ( typeof ( *dhcphdr ), options ) );
+
+ /* Verify client identifier */
+ if ( ( rc = dhcpv6_check_duid ( &options, DHCPV6_CLIENT_ID,
+ dhcpv6->client_duid,
+ dhcpv6->client_duid_len ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s without correct client "
+ "ID: %s\n", dhcpv6->netdev->name,
+ dhcpv6_type_name ( dhcphdr->type ), strerror ( rc ) );
+ goto done;
+ }
+
+ /* Verify server identifier, if applicable */
+ if ( dhcpv6->server_duid &&
+ ( ( rc = dhcpv6_check_duid ( &options, DHCPV6_SERVER_ID,
+ dhcpv6->server_duid,
+ dhcpv6->server_duid_len ) ) != 0 ) ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s without correct server "
+ "ID: %s\n", dhcpv6->netdev->name,
+ dhcpv6_type_name ( dhcphdr->type ), strerror ( rc ) );
+ goto done;
+ }
+
+ /* Check message type */
+ if ( dhcphdr->type != dhcpv6->state->rx_type ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s while expecting %s\n",
+ dhcpv6->netdev->name, dhcpv6_type_name ( dhcphdr->type ),
+ dhcpv6_type_name ( dhcpv6->state->rx_type ) );
+ rc = -ENOTTY;
+ goto done;
+ }
+
+ /* Fetch status code, if present */
+ if ( ( rc = dhcpv6_status_code ( &options ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s with error status: %s\n",
+ dhcpv6->netdev->name, dhcpv6_type_name ( dhcphdr->type ),
+ strerror ( rc ) );
+ /* This is plausibly the error we want to return */
+ dhcpv6->rc = rc;
+ goto done;
+ }
+
+ /* Record identity association address, if applicable */
+ if ( dhcpv6->state->flags & DHCPV6_RX_IAADDR ) {
+ if ( ( rc = dhcpv6_iaaddr ( &options, dhcpv6->iaid,
+ &dhcpv6->lease ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s with unusable "
+ "IAADDR: %s\n", dhcpv6->netdev->name,
+ dhcpv6_type_name ( dhcphdr->type ),
+ strerror ( rc ) );
+ /* This is plausibly the error we want to return */
+ dhcpv6->rc = rc;
+ goto done;
+ }
+ DBGC ( dhcpv6, "DHCPv6 %s received %s is for %s\n",
+ dhcpv6->netdev->name, dhcpv6_type_name ( dhcphdr->type ),
+ inet6_ntoa ( &dhcpv6->lease ) );
+ }
+
+ /* Record server ID, if applicable */
+ if ( dhcpv6->state->flags & DHCPV6_RX_SERVER_ID ) {
+ assert ( dhcpv6->server_duid == NULL );
+ option = dhcpv6_option ( &options, DHCPV6_SERVER_ID );
+ if ( ! option ) {
+ DBGC ( dhcpv6, "DHCPv6 %s received %s missing server "
+ "ID\n", dhcpv6->netdev->name,
+ dhcpv6_type_name ( dhcphdr->type ) );
+ rc = -EINVAL;
+ goto done;
+ }
+ dhcpv6->server_duid_len = ntohs ( option->duid.header.len );
+ dhcpv6->server_duid = malloc ( dhcpv6->server_duid_len );
+ if ( ! dhcpv6->server_duid ) {
+ rc = -ENOMEM;
+ goto done;
+ }
+ memcpy ( dhcpv6->server_duid, option->duid.duid,
+ dhcpv6->server_duid_len );
+ }
+
+ /* Transition to next state or complete DHCPv6, as applicable */
+ if ( dhcpv6->state->next ) {
+
+ /* Transition to next state */
+ dhcpv6_set_state ( dhcpv6, dhcpv6->state->next );
+ rc = 0;
+
+ } else {
+
+ /* Register settings */
+ if ( ( rc = dhcpv6_register ( &options, parent ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s could not register "
+ "settings: %s\n", dhcpv6->netdev->name,
+ strerror ( rc ) );
+ goto done;
+ }
+
+ /* Mark as complete */
+ dhcpv6_finished ( dhcpv6, 0 );
+ DBGC ( dhcpv6, "DHCPv6 %s complete\n", dhcpv6->netdev->name );
+ }
+
+ done:
+ free_iob ( iobuf );
+ return rc;
+}
+
+/** DHCPv6 job control interface operations */
+static struct interface_operation dhcpv6_job_op[] = {
+ INTF_OP ( intf_close, struct dhcpv6_session *, dhcpv6_finished ),
+};
+
+/** DHCPv6 job control interface descriptor */
+static struct interface_descriptor dhcpv6_job_desc =
+ INTF_DESC ( struct dhcpv6_session, job, dhcpv6_job_op );
+
+/** DHCPv6 data transfer interface operations */
+static struct interface_operation dhcpv6_xfer_op[] = {
+ INTF_OP ( xfer_deliver, struct dhcpv6_session *, dhcpv6_rx ),
+};
+
+/** DHCPv6 data transfer interface descriptor */
+static struct interface_descriptor dhcpv6_xfer_desc =
+ INTF_DESC ( struct dhcpv6_session, xfer, dhcpv6_xfer_op );
+
+/**
+ * Start DHCPv6
+ *
+ * @v job Job control interface
+ * @v netdev Network device
+ * @v stateful Perform stateful address autoconfiguration
+ * @ret rc Return status code
+ */
+int start_dhcpv6 ( struct interface *job, struct net_device *netdev,
+ int stateful ) {
+ struct ll_protocol *ll_protocol = netdev->ll_protocol;
+ struct dhcpv6_session *dhcpv6;
+ struct {
+ union {
+ struct sockaddr_in6 sin6;
+ struct sockaddr sa;
+ } client;
+ union {
+ struct sockaddr_in6 sin6;
+ struct sockaddr sa;
+ } server;
+ } addresses;
+ struct dhcpv6_duid_ll *client_duid;
+ size_t client_duid_len;
+ uint32_t xid;
+ int rc;
+
+ /* Allocate and initialise structure */
+ client_duid_len = ( sizeof ( *client_duid ) + ll_protocol->ll_addr_len);
+ dhcpv6 = zalloc ( sizeof ( *dhcpv6 ) + client_duid_len );
+ if ( ! dhcpv6 )
+ return -ENOMEM;
+ ref_init ( &dhcpv6->refcnt, dhcpv6_free );
+ intf_init ( &dhcpv6->job, &dhcpv6_job_desc, &dhcpv6->refcnt );
+ intf_init ( &dhcpv6->xfer, &dhcpv6_xfer_desc, &dhcpv6->refcnt );
+ dhcpv6->netdev = netdev_get ( netdev );
+ xid = random();
+ memcpy ( dhcpv6->xid, &xid, sizeof ( dhcpv6->xid ) );
+ dhcpv6->start = currticks();
+ dhcpv6->client_duid = ( ( ( void * ) dhcpv6 ) + sizeof ( *dhcpv6 ) );
+ dhcpv6->client_duid_len = client_duid_len;
+ timer_init ( &dhcpv6->timer, dhcpv6_timer_expired, &dhcpv6->refcnt );
+
+ /* Construct client and server addresses */
+ memset ( &addresses, 0, sizeof ( addresses ) );
+ addresses.client.sin6.sin6_family = AF_INET6;
+ addresses.client.sin6.sin6_scope_id = netdev->index;
+ addresses.client.sin6.sin6_port = htons ( DHCPV6_CLIENT_PORT );
+ addresses.server.sin6.sin6_family = AF_INET6;
+ ipv6_all_dhcp_relay_and_servers ( &addresses.server.sin6.sin6_addr );
+ addresses.server.sin6.sin6_scope_id = netdev->index;
+ addresses.server.sin6.sin6_port = htons ( DHCPV6_SERVER_PORT );
+
+ /* Construct client DUID and IAID from link-layer address */
+ client_duid = dhcpv6->client_duid;
+ client_duid->type = htons ( DHCPV6_DUID_LL );
+ client_duid->htype = ll_protocol->ll_proto;
+ memcpy ( client_duid->ll_addr, netdev->ll_addr,
+ ll_protocol->ll_addr_len );
+ dhcpv6->iaid = crc32_le ( 0, netdev->ll_addr, ll_protocol->ll_addr_len);
+ DBGC ( dhcpv6, "DHCPv6 %s has XID %02x%02x%02x\n", dhcpv6->netdev->name,
+ dhcpv6->xid[0], dhcpv6->xid[1], dhcpv6->xid[2] );
+
+ /* Enter initial state */
+ dhcpv6_set_state ( dhcpv6, ( stateful ? &dhcpv6_solicit :
+ &dhcpv6_information_request ) );
+
+ /* Open socket */
+ if ( ( rc = xfer_open_socket ( &dhcpv6->xfer, SOCK_DGRAM,
+ &addresses.server.sa,
+ &addresses.client.sa ) ) != 0 ) {
+ DBGC ( dhcpv6, "DHCPv6 %s could not open socket: %s\n",
+ dhcpv6->netdev->name, strerror ( rc ) );
+ goto err_open_socket;
+ }
+
+ /* Attach parent interface, mortalise self, and return */
+ intf_plug_plug ( &dhcpv6->job, job );
+ ref_put ( &dhcpv6->refcnt );
+ return 0;
+
+ err_open_socket:
+ dhcpv6_finished ( dhcpv6, rc );
+ ref_put ( &dhcpv6->refcnt );
+ return rc;
+}