add initial support for stateless DHCPv6

Signed-off-by: goldsimon <goldsimon@gmx.de>
2026-05-12 19:26:52 +08:00 · 2018-02-22 22:33:16 +01:00
parent 37b4494921
commit 76a13054ee
7 changed files with 909 additions and 28 deletions
--- a/src/include/lwip/dhcp6.h
+++ b/src/include/lwip/dhcp6.h
@@ -1,11 +1,13 @@
 /**
 * @file
 *
- * IPv6 address autoconfiguration as per RFC 4862.
+ * DHCPv6 client: IPv6 address autoconfiguration as per
+ * RFC 3315 (stateful DHCPv6) and
+ * RFC 3736 (stateless DHCPv6).
 */

 /*
- * Copyright (c) 2010 Inico Technologies Ltd.
+ * Copyright (c) 2018 Simon Goldschmidt
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
@@ -32,12 +34,7 @@
 *
 * This file is part of the lwIP TCP/IP stack.
 *
- * Author: Ivan Delamer <delamer@inicotech.com>
- *
- * IPv6 address autoconfiguration as per RFC 4862.
- *
- * Please coordinate changes and requests with Ivan Delamer
- * <delamer@inicotech.com>
+ * Author: Simon Goldschmidt <goldsimon@gmx.de>
 */

 #ifndef LWIP_HDR_IP6_DHCP6_H
@@ -47,12 +44,53 @@

 #if LWIP_IPV6_DHCP6  /* don't build if not configured for use in lwipopts.h */

+#include "lwip/err.h"
+#include "lwip/netif.h"
+
+/** period (in milliseconds) of the application calling dhcp6_tmr() */
+#define DHCP6_TIMER_MSECS   500

 struct dhcp6
 {
-  /*@todo: implement DHCP6*/
+  /** transaction identifier of last sent request */
+  u32_t xid;
+  /** track PCB allocation state */
+  u8_t pcb_allocated;
+  /** current DHCPv6 state machine state */
+  u8_t state;
+  /** retries of current request */
+  u8_t tries;
+  /** if request config is triggered while another action is active, this keeps track of it */
+  u8_t request_config_pending;
+  /** #ticks with period DHCP6_TIMER_MSECS for request timeout */
+  u16_t request_timeout;
+#if LWIP_IPV6_DHCP6_STATEFUL
+  /* @todo: add more members here to keep track of stateful DHCPv6 data, like lease times */
+#endif /* LWIP_IPV6_DHCP6_STATEFUL */
 };

+void dhcp6_set_struct(struct netif *netif, struct dhcp6 *dhcp6);
+/** Remove a struct dhcp6 previously set to the netif using dhcp6_set_struct() */
+#define dhcp6_remove_struct(netif) netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6, NULL)
+void dhcp6_cleanup(struct netif *netif);
+
+err_t dhcp6_enable_stateful(struct netif *netif);
+err_t dhcp6_enable_stateless(struct netif *netif);
+void dhcp6_disable(struct netif *netif);
+
+void dhcp6_tmr(void);
+
+void dhcp6_nd6_ra_trigger(struct netif *netif, u8_t managed_addr_config, u8_t other_config);
+
+#if LWIP_DHCP6_GET_NTP_SRV
+/** This function must exist, in other to add offered NTP servers to
+ * the NTP (or SNTP) engine.
+ * See LWIP_DHCP6_MAX_NTP_SERVERS */
+extern void dhcp6_set_ntp_servers(u8_t num_ntp_servers, const ip_addr_t* ntp_server_addrs);
+#endif /* LWIP_DHCP6_GET_NTP_SRV */
+
+#define netif_dhcp6_data(netif) ((struct dhcp6*)netif_get_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6))
+
 #endif /* LWIP_IPV6_DHCP6 */

 #endif /* LWIP_HDR_IP6_DHCP6_H */
--- a/src/include/lwip/netif.h
+++ b/src/include/lwip/netif.h
@@ -112,6 +112,7 @@ extern "C" {

 enum lwip_internal_netif_client_data_index
 {
+#if LWIP_IPV4
 #if LWIP_DHCP
   LWIP_NETIF_CLIENT_DATA_INDEX_DHCP,
 #endif
@@ -121,9 +122,15 @@ enum lwip_internal_netif_client_data_index
 #if LWIP_IGMP
   LWIP_NETIF_CLIENT_DATA_INDEX_IGMP,
 #endif
+#endif /* LWIP_IPV4 */
+#if LWIP_IPV6
+#if LWIP_IPV6_DHCP6
+   LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6,
+#endif
 #if LWIP_IPV6_MLD
   LWIP_NETIF_CLIENT_DATA_INDEX_MLD6,
 #endif
+#endif /* LWIP_IPV6 */
   LWIP_NETIF_CLIENT_DATA_INDEX_MAX
 };

--- a/src/include/lwip/opt.h
+++ b/src/include/lwip/opt.h
@@ -963,7 +963,7 @@

 /**
 * LWIP_DHCP_MAX_DNS_SERVERS > 0: Request DNS servers with discover/select.
- * DHCP servers received in the response are passed to DNS via @ref dns_setserver()
+ * DNS servers received in the response are passed to DNS via @ref dns_setserver()
 * (up to the maximum limit defined here).
 */
 #if !defined LWIP_DHCP_MAX_DNS_SERVERS || defined __DOXYGEN__
@@ -2657,12 +2657,51 @@
 */

 /**
- * LWIP_IPV6_DHCP6==1: enable DHCPv6 stateful address autoconfiguration.
+ * LWIP_IPV6_DHCP6==1: enable DHCPv6 stateful/stateless address autoconfiguration.
 */
 #if !defined LWIP_IPV6_DHCP6 || defined __DOXYGEN__
 #define LWIP_IPV6_DHCP6                 0
 #endif

+/**
+ * LWIP_IPV6_DHCP6_STATEFUL==1: enable DHCPv6 stateful address autoconfiguration.
+ */
+#if !defined LWIP_IPV6_DHCP6_STATEFUL || defined __DOXYGEN__
+#define LWIP_IPV6_DHCP6_STATEFUL        0
+#endif
+
+/**
+ * LWIP_IPV6_DHCP6_STATELESS==1: enable DHCPv6 stateless address autoconfiguration.
+ */
+#if !defined LWIP_IPV6_DHCP6_STATELESS || defined __DOXYGEN__
+#define LWIP_IPV6_DHCP6_STATELESS       0
+#endif
+
+/**
+ * LWIP_DHCP6_GETS_NTP==1: Request NTP servers via DHCPv6. For each
+ * response packet, a callback is called, which has to be provided by the port:
+ * void dhcp6_set_ntp_servers(u8_t num_ntp_servers, ip_addr_t* ntp_server_addrs);
+*/
+#if !defined LWIP_DHCP6_GET_NTP_SRV || defined __DOXYGEN__
+#define LWIP_DHCP6_GET_NTP_SRV          0
+#endif
+
+/**
+ * The maximum of NTP servers requested
+ */
+#if !defined LWIP_DHCP6_MAX_NTP_SERVERS || defined __DOXYGEN__
+#define LWIP_DHCP6_MAX_NTP_SERVERS      1
+#endif
+
+/**
+ * LWIP_DHCP6_MAX_DNS_SERVERS > 0: Request DNS servers via DHCPv6.
+ * DNS servers received in the response are passed to DNS via @ref dns_setserver()
+ * (up to the maximum limit defined here).
+ */
+#if !defined LWIP_DHCP6_MAX_DNS_SERVERS || defined __DOXYGEN__
+#define LWIP_DHCP6_MAX_DNS_SERVERS      DNS_MAX_SERVERS
+#endif
+
 /*
   ---------------------------------------
   ---------- Hook options ---------------
@@ -3047,6 +3086,34 @@
 #define LWIP_HOOK_DHCP_PARSE_OPTION(netif, dhcp, state, msg, msg_type, option, len, pbuf, offset)
 #endif

+/**
+ * LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len):
+ * Called from various dhcp6 functions when sending a DHCP6 message.
+ * This hook is called just before the DHCP6 message is sent, so the
+ * options are at the end of a DHCP6 message.
+ * Signature:\code{.c}
+ *   void my_hook(struct netif *netif, struct dhcp6 *dhcp, u8_t state, struct dhcp6_msg *msg,
+ *                u8_t msg_type, u16_t *options_len_ptr);
+ * \endcode
+ * Arguments:
+ * - netif: struct netif that the packet will be sent through
+ * - dhcp6: struct dhcp6 on that netif
+ * - state: current dhcp6 state (dhcp6_state_enum_t as an u8_t)
+ * - msg: struct dhcp6_msg that will be sent
+ * - msg_type: dhcp6 message type to be sent (u8_t)
+ * - options_len_ptr: pointer to the current length of options in the dhcp6_msg "msg"
+ *                    (must be increased when options are added!)
+ *
+ * Options need to appended like this:
+ *   u8_t *options = (u8_t *)(msg + 1);
+ *   LWIP_ASSERT("dhcp option overflow", sizeof(struct dhcp6_msg) + *options_len_ptr + newoptlen <= max_len);
+ *   options[(*options_len_ptr)++] = &lt;option_data&gt;;
+ *   [...]
+ */
+#ifdef __DOXYGEN__
+#define LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len)
+#endif
+
 /**
 * LWIP_HOOK_SOCKETS_SETSOCKOPT(s, sock, level, optname, optval, optlen, err)
 * Called from socket API to implement setsockopt() for options not provided by lwIP.
@@ -3372,6 +3439,13 @@
 #if !defined IP6_DEBUG || defined __DOXYGEN__
 #define IP6_DEBUG                       LWIP_DBG_OFF
 #endif
+
+/**
+ * DHCP6_DEBUG: Enable debugging in dhcp6.c.
+ */
+#if !defined DHCP6_DEBUG || defined __DOXYGEN__
+#define DHCP6_DEBUG                     LWIP_DBG_OFF
+#endif
 /**
 * @}
 */
--- a/src/include/lwip/prot/dhcp6.h
+++ b/src/include/lwip/prot/dhcp6.h
@@ -49,12 +49,6 @@ extern "C" {

 /* DHCPv6 message item offsets and length */
 #define DHCP6_TRANSACTION_ID_LEN   3
-#define DHCP_SNAME_OFS    44U
-#define DHCP_SNAME_LEN    64U
-#define DHCP_FILE_OFS     108U
-#define DHCP_FILE_LEN     128U
-#define DHCP_MSG_LEN      236U
-#define DHCP_OPTIONS_OFS  (DHCP_MSG_LEN + 4U)*/ /* 4 byte: cookie */

 #ifdef PACK_STRUCT_USE_INCLUDES
 #  include "arch/bpstruct.h"
@@ -76,8 +70,9 @@ PACK_STRUCT_END
 /* DHCP6 client states */
 typedef enum {
  DHCP6_STATE_OFF               = 0,
-  DHCP6_STATE_REQUESTING_CONFIG = 1
-} dhcp_state_enum_t;
+  DHCP6_STATE_STATELESS_IDLE    = 1,
+  DHCP6_STATE_REQUESTING_CONFIG = 2
+} dhcp6_state_enum_t;

 /* DHCPv6 message types */
 #define DHCP6_SOLICIT               1
@@ -93,6 +88,7 @@ typedef enum {
 #define DHCP6_INFOREQUEST           11
 #define DHCP6_RELAYFORW             12
 #define DHCP6_RELAYREPL             13
+/* More message types see https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml */

 /** DHCPv6 status codes */
 #define DHCP6_STATUS_SUCCESS        0 /* Success. */
@@ -101,11 +97,13 @@ typedef enum {
 #define DHCP6_STATUS_NOBINDING      3 /* Client record (binding) unavailable. */
 #define DHCP6_STATUS_NOTONLINK      4 /* The prefix for the address is not appropriate for the link to which the client is attached. */
 #define DHCP6_STATUS_USEMULTICAST   5 /* Sent by a server to a client to force the client to send messages to the server using the All_DHCP_Relay_Agents_and_Servers address. */
+/* More status codes see https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml */

 /** DHCPv6 DUID types */
 #define DHCP6_DUID_LLT              1 /* LLT: Link-layer Address Plus Time */
 #define DHCP6_DUID_EN               2 /* EN: Enterprise number */
 #define DHCP6_DUID_LL               3 /* LL: Link-layer Address */
+#define DHCP6_DUID_UUID             4 /* UUID (RFC 6355) */

 /* DHCPv6 options */
 #define DHCP6_OPTION_CLIENTID       1
@@ -126,7 +124,11 @@ typedef enum {
 #define DHCP6_OPTION_VENDOR_OPTS    17
 #define DHCP6_OPTION_INTERFACE_ID   18
 #define DHCP6_OPTION_RECONF_MSG     19
-#define DHCP6_OPTION_ACCEPT         20
+#define DHCP6_OPTION_RECONF_ACCEPT  20
+/* More options see https://www.iana.org/assignments/dhcpv6-parameters/dhcpv6-parameters.xhtml */
+#define DHCP6_OPTION_DNS_SERVERS    23 /* RFC 3646 */
+#define DHCP6_OPTION_DOMAIN_LIST    24 /* RFC 3646 */
+#define DHCP6_OPTION_SNTP_SERVERS   31 /* RFC 4075 */


 #ifdef __cplusplus