BadVPN – Rev 1
?pathlinks?
/**
* @file
* DHCPv6 - RFC 3315
*/
/*
* Copyright (c) 2017 Simon Goldschmidt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Simon Goldschmidt <goldsimon@gmx.de>
*/
#include "lwip/opt.h"
#if LWIP_IPV6 && LWIP_IPV6_DHCP6 /* don't build if not configured for use in lwipopts.h */
#include "lwip/dhcp6.h"
#include "lwip/prot/dhcp6.h"
#include "lwip/def.h"
#include "lwip/udp.h"
#include <string.h>
#ifdef LWIP_HOOK_FILENAME
#include LWIP_HOOK_FILENAME
#endif
#ifndef LWIP_HOOK_DHCP6_APPEND_OPTIONS
#define LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type)
#endif
#ifndef LWIP_HOOK_DHCP6_PARSE_OPTION
#define LWIP_HOOK_DHCP6_PARSE_OPTION(netif, dhcp6, state, msg, msg_type, option, len, pbuf, offset)
#endif
const ip_addr_t dhcp6_All_DHCP_Relay_Agents_and_Servers = IPADDR6_INIT_HOST(0xFF020000, 0, 0, 0x00010002);
const ip_addr_t dhcp6_All_DHCP_Servers = IPADDR6_INIT_HOST(0xFF020000, 0, 0, 0x00010003);
static struct udp_pcb *dhcp6_pcb;
static u8_t dhcp6_pcb_refcount;
/* receive, unfold, parse and free incoming messages */
static void dhcp6_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port);
/** Ensure DHCP PCB is allocated and bound */
static err_t
dhcp6_inc_pcb_refcount(void)
{
if (dhcp6_pcb_refcount == 0) {
LWIP_ASSERT("dhcp6_inc_pcb_refcount(): memory leak", dhcp6_pcb == NULL);
/* allocate UDP PCB */
dhcp6_pcb = udp_new();
if (dhcp6_pcb == NULL) {
return ERR_MEM;
}
ip_set_option(dhcp6_pcb, SOF_BROADCAST);
/* set up local and remote port for the pcb -> listen on all interfaces on all src/dest IPs */
udp_bind(dhcp6_pcb, IP6_ADDR_ANY, DHCP6_CLIENT_PORT);
udp_recv(dhcp6_pcb, dhcp6_recv, NULL);
}
dhcp6_pcb_refcount++;
return ERR_OK;
}
/** Free DHCP PCB if the last netif stops using it */
static void
dhcp6_dec_pcb_refcount(void)
{
LWIP_ASSERT("dhcp6_pcb_refcount(): refcount error", (dhcp6_pcb_refcount > 0));
dhcp6_pcb_refcount--;
if (dhcp6_pcb_refcount == 0) {
udp_remove(dhcp6_pcb);
dhcp6_pcb = NULL;
}
}
/**
* @ingroup dhcp6
* Set a statically allocated struct dhcp6 to work with.
* Using this prevents dhcp6_start to allocate it using mem_malloc.
*
* @param netif the netif for which to set the struct dhcp
* @param dhcp6 (uninitialised) dhcp6 struct allocated by the application
*/
void
dhcp6_set_struct(struct netif *netif, struct dhcp6 *dhcp6)
{
LWIP_ASSERT("netif != NULL", netif != NULL);
LWIP_ASSERT("dhcp6 != NULL", dhcp6 != NULL);
LWIP_ASSERT("netif already has a struct dhcp6 set", netif_dhcp6_data(netif) == NULL);
/* clear data structure */
memset(dhcp6, 0, sizeof(struct dhcp6));
/* dhcp_set_state(&dhcp, DHCP_STATE_OFF); */
netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6, dhcp6);
}
/**
* @ingroup dhcp6
* Removes a struct dhcp6 from a netif.
*
* ATTENTION: Only use this when not using dhcp6_set_struct() to allocate the
* struct dhcp6 since the memory is passed back to the heap.
*
* @param netif the netif from which to remove the struct dhcp
*/
void dhcp6_cleanup(struct netif *netif)
{
LWIP_ASSERT("netif != NULL", netif != NULL);
if (netif_dhcp6_data(netif) != NULL) {
mem_free(netif_dhcp6_data(netif));
netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6, NULL);
}
}
static struct dhcp6*
dhcp6_get_struct(struct netif *netif, const char *dbg_requester)
{
struct dhcp6 *dhcp6 = netif_dhcp6_data(netif);
if (dhcp6 == NULL) {
LWIP_DEBUGF(DHCP6_DEBUG | LWIP_DBG_TRACE, ("%s: mallocing new DHCPv6 client\n", dbg_requester));
dhcp6 = (struct dhcp6 *)mem_malloc(sizeof(struct dhcp6));
if (dhcp6 == NULL) {
LWIP_DEBUGF(DHCP6_DEBUG | LWIP_DBG_TRACE, ("%s: could not allocate dhcp6\n", dbg_requester));
return NULL;
}
/* clear data structure, this implies DHCP6_STATE_OFF */
memset(dhcp6, 0, sizeof(struct dhcp6));
/* store this dhcp6 client in the netif */
netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6, dhcp6);
} else {
/* already has DHCP6 client attached */
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("%s: using existing DHCPv6 client\n", dbg_requester));
}
if (!dhcp6->pcb_allocated) {
if (dhcp6_inc_pcb_refcount() != ERR_OK) { /* ensure DHCP6 PCB is allocated */
mem_free(dhcp6);
netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP6, NULL);
return NULL;
}
LWIP_DEBUGF(DHCP6_DEBUG | LWIP_DBG_TRACE, ("%s: allocated dhcp6", dbg_requester));
dhcp6->pcb_allocated = 1;
}
return dhcp6;
}
static u32_t
dhcp6_create_next_xid(struct netif *netif, struct dhcp6 dhcp6)
{
LWIP_UNUSED_ARG(netif);
LWIP_UNUSED_ARG(dhcp6);
}
#if LWIP_IPV6_DHCP6_STATELESS
static err_t
dhcp_information_request(struct netif *netif, struct dhcp6 *dhcp6)
{
struct dhcp *dhcp = netif_dhcp_data(netif);
err_t result = ERR_OK;
u16_t msecs;
u8_t i;
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover()\n"));
ip4_addr_set_any(&dhcp->offered_ip_addr);
dhcp_set_state(dhcp, DHCP_STATE_SELECTING);
/* create and initialize the DHCP message header */
result = dhcp_create_msg(netif, dhcp, DHCP_DISCOVER);
if (result == ERR_OK) {
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: making request\n"));
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
dhcp_option_short(dhcp, DHCP_MAX_MSG_LEN(netif));
dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, LWIP_ARRAYSIZE(dhcp_discover_request_options));
for (i = 0; i < LWIP_ARRAYSIZE(dhcp_discover_request_options); i++) {
dhcp_option_byte(dhcp, dhcp_discover_request_options[i]);
}
LWIP_HOOK_DHCP_APPEND_OPTIONS(netif, dhcp, DHCP_STATE_SELECTING, dhcp->msg_out, DHCP_DISCOVER);
dhcp_option_trailer(dhcp);
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: sendto(DISCOVER, IP_ADDR_BROADCAST, DHCP_SERVER_PORT)\n"));
udp_sendto_if_src(dhcp_pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif, IP4_ADDR_ANY);
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: deleting()ing\n"));
dhcp_delete_msg(dhcp);
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover: SELECTING\n"));
} else {
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("dhcp_discover: could not allocate DHCP request\n"));
}
if (dhcp->tries < 255) {
dhcp->tries++;
}
#if LWIP_DHCP_AUTOIP_COOP
if (dhcp->tries >= LWIP_DHCP_AUTOIP_COOP_TRIES && dhcp->autoip_coop_state == DHCP_AUTOIP_COOP_STATE_OFF) {
dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_ON;
autoip_start(netif);
}
#endif /* LWIP_DHCP_AUTOIP_COOP */
msecs = (u16_t)((dhcp->tries < 6 ? 1 << dhcp->tries : 60) * 1000);
dhcp->request_timeout = (u16_t)((msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS);
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover(): set request timeout %"U16_F" msecs\n", msecs));
return result;
}
static err_t
dhcp6_request_config(struct netif *netif)
{
struct dhcp6 *dhcp6;
LWIP_ASSERT("netif != NULL", netif != NULL);
dhcp6 = dhcp6_get_struct(netif, "dhcp6_request_config()");
if (dhcp6 == NULL) {
return ERR_MEM;
}
/* if state is not idle, set a flag to send an information-request later? */
if (dhcp6->state != DHCP6_STATE_OFF) {
dhcp6->request_config_pending = 1;
return ERR_OK;
}
/* send Information-request and wait for answer; setup receive timeout */
dhcp_information_request(netif, dhcp6);
return ERR_OK;
}
#endif /* LWIP_IPV6_DHCP6_STATELESS */
void
dhcp6_nd6_ra_trigger(struct netif *netif, u8_t managed_addr_config, u8_t other_config)
{
LWIP_UNUSED_ARG(managed_addr_config);
LWIP_UNUSED_ARG(other_config);
#if LWIP_IPV6_DHCP6_STATELESS
if (other_config) {
dhcp6_request_config(netif);
}
#endif /* LWIP_IPV6_DHCP6_STATELESS */
}
static void
dhcp6_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
{
LWIP_UNUSED_ARG(arg);
LWIP_UNUSED_ARG(pcb);
LWIP_UNUSED_ARG(p);
LWIP_UNUSED_ARG(addr);
LWIP_UNUSED_ARG(port);
}
#endif /* LWIP_IPV6 && LWIP_IPV6_DHCP6 */