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Diffstat (limited to 'src/core/ipv4/autoip.c')
| -rw-r--r-- | src/core/ipv4/autoip.c | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/src/core/ipv4/autoip.c b/src/core/ipv4/autoip.c new file mode 100644 index 00000000000..461a005338f --- /dev/null +++ b/src/core/ipv4/autoip.c @@ -0,0 +1,379 @@ +/** + * @file + * AutoIP Automatic LinkLocal IP Configuration + * + * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform + * with RFC 3927. It uses IPv4 address conflict detection to evaluate the chosen + * address. The ACD module aims to be conform to RFC 5227. + * RFC 5227 is extracted out of RFC 3927 so the acd module fits nicely in autoip. + * + * @defgroup autoip AUTOIP + * @ingroup ip4 + * AUTOIP related functions + * USAGE: + * + * define @ref LWIP_AUTOIP 1 in your lwipopts.h + * + * Without DHCP: + * - Call autoip_start() after netif_add(). + * + * With DHCP: + * - define @ref LWIP_DHCP_AUTOIP_COOP 1 in your lwipopts.h. + * - Configure your DHCP Client. + * + * @see netifapi_autoip + */ + +/* + * + * Copyright (c) 2007 Dominik Spies <kontakt@dspies.de> + * 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. + * + * Author: Dominik Spies <kontakt@dspies.de> + */ + +#include "lwip/opt.h" + +#if LWIP_IPV4 && LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */ + +#include "lwip/mem.h" +/* #include "lwip/udp.h" */ +#include "lwip/ip_addr.h" +#include "lwip/netif.h" +#include "lwip/autoip.h" +#include "lwip/acd.h" +#include "lwip/etharp.h" +#include "lwip/prot/autoip.h" + +#include <string.h> + +/** + * Macro that generates the initial IP address to be tried by AUTOIP. + * If you want to override this, define it to something else in lwipopts.h. + */ +#ifndef LWIP_AUTOIP_CREATE_SEED_ADDR +#define LWIP_AUTOIP_CREATE_SEED_ADDR(netif) \ + lwip_htonl(AUTOIP_RANGE_START + ((u32_t)(((u8_t)(netif->hwaddr[4])) | \ + ((u32_t)((u8_t)(netif->hwaddr[5]))) << 8))) +#endif /* LWIP_AUTOIP_CREATE_SEED_ADDR */ + +/* Function definitions */ +static void autoip_restart(struct netif *netif); +static void autoip_create_addr(struct netif *netif, ip4_addr_t *ipaddr); +static err_t autoip_bind(struct netif *netif); +static void autoip_conflict_callback(struct netif *netif, + acd_callback_enum_t state); + +/** + * @ingroup autoip + * Set a statically allocated struct autoip to work with. + * Using this prevents autoip_start to allocate it using mem_malloc. + * + * @param netif the netif for which to set the struct autoip + * @param autoip (uninitialised) autoip struct allocated by the application + */ +void +autoip_set_struct(struct netif *netif, struct autoip *autoip) +{ + LWIP_ASSERT_CORE_LOCKED(); + LWIP_ASSERT("netif != NULL", netif != NULL); + LWIP_ASSERT("autoip != NULL", autoip != NULL); + LWIP_ASSERT("netif already has a struct autoip set", + netif_autoip_data(netif) == NULL); + + /* clear data structure */ + memset(autoip, 0, sizeof(struct autoip)); + /* autoip->state = AUTOIP_STATE_OFF; */ + netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_AUTOIP, autoip); +} + +/** + * @ingroup autoip + * Remove a struct autoip previously set to the netif using autoip_set_struct() + * + * @param netif the netif for which to set the struct autoip + */ +void +autoip_remove_struct(struct netif *netif) +{ + LWIP_ASSERT_CORE_LOCKED(); + LWIP_ASSERT("netif != NULL", netif != NULL); + LWIP_ASSERT("netif has no struct autoip set", + netif_autoip_data(netif) != NULL); + + netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_AUTOIP, NULL); +} + +/** Restart AutoIP client and check the next address (conflict detected) + * + * @param netif The netif under AutoIP control + */ +static void +autoip_restart(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + autoip->tried_llipaddr++; + autoip_start(netif); +} + + +/** + * Create an IP-Address out of range 169.254.1.0 to 169.254.254.255 + * + * @param netif network interface on which create the IP-Address + * @param ipaddr ip address to initialize + */ +static void +autoip_create_addr(struct netif *netif, ip4_addr_t *ipaddr) +{ + struct autoip *autoip = netif_autoip_data(netif); + + /* Here we create an IP-Address out of range 169.254.1.0 to 169.254.254.255 + * compliant to RFC 3927 Section 2.1 + * We have 254 * 256 possibilities */ + + u32_t addr = lwip_ntohl(LWIP_AUTOIP_CREATE_SEED_ADDR(netif)); + addr += autoip->tried_llipaddr; + addr = AUTOIP_NET | (addr & 0xffff); + /* Now, 169.254.0.0 <= addr <= 169.254.255.255 */ + + if (addr < AUTOIP_RANGE_START) { + addr += AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1; + } + if (addr > AUTOIP_RANGE_END) { + addr -= AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1; + } + LWIP_ASSERT("AUTOIP address not in range", (addr >= AUTOIP_RANGE_START) && + (addr <= AUTOIP_RANGE_END)); + ip4_addr_set_u32(ipaddr, lwip_htonl(addr)); + + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, + ("autoip_create_addr(): tried_llipaddr=%"U16_F", %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", + (u16_t)(autoip->tried_llipaddr), ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), + ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr))); +} + + +/** + * Configure interface for use with current LL IP-Address + * + * @param netif network interface to configure with current LL IP-Address + */ +static err_t +autoip_bind(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + ip4_addr_t sn_mask, gw_addr; + + autoip->state = AUTOIP_STATE_BOUND; + + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_bind(netif=%p) %c%c%"U16_F" %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", + (void *)netif, netif->name[0], netif->name[1], (u16_t)netif->num, + ip4_addr1_16(&autoip->llipaddr), ip4_addr2_16(&autoip->llipaddr), + ip4_addr3_16(&autoip->llipaddr), ip4_addr4_16(&autoip->llipaddr))); + + IP4_ADDR(&sn_mask, 255, 255, 0, 0); + IP4_ADDR(&gw_addr, 0, 0, 0, 0); + + netif_set_addr(netif, &autoip->llipaddr, &sn_mask, &gw_addr); + /* interface is used by routing now that an address is set */ + + return ERR_OK; +} + +/** +* Handle conflict information from ACD module +* +* @param netif network interface to handle conflict information on +* @param state acd_callback_enum_t + */ +static void +autoip_conflict_callback(struct netif *netif, acd_callback_enum_t state) +{ + struct autoip *autoip = netif_autoip_data(netif); + + switch (state) { + case ACD_IP_OK: + autoip_bind(netif); + break; + case ACD_RESTART_CLIENT: + autoip_restart(netif); + break; + case ACD_DECLINE: + /* "delete" conflicting address so a new one will be selected in + * autoip_start() */ + ip4_addr_set_any(&autoip->llipaddr); + autoip_stop(netif); + break; + default: + break; + } +} + +/** + * @ingroup autoip + * Start AutoIP client + * + * @param netif network interface on which start the AutoIP client + */ +err_t +autoip_start(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + err_t result = ERR_OK; + + LWIP_ASSERT_CORE_LOCKED(); + LWIP_ERROR("netif is not up, old style port?", netif_is_up(netif), return ERR_ARG;); + + if (autoip == NULL) { + /* no AutoIP client attached yet? */ + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_start(): starting new AUTOIP client\n")); + autoip = (struct autoip *)mem_calloc(1, sizeof(struct autoip)); + if (autoip == NULL) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_start(): could not allocate autoip\n")); + return ERR_MEM; + } + /* store this AutoIP client in the netif */ + netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_AUTOIP, autoip); + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_start(): allocated autoip\n")); + } + + if (autoip->state == AUTOIP_STATE_OFF) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, + ("autoip_start(netif=%p) %c%c%"U16_F"\n", (void *)netif, netif->name[0], + netif->name[1], (u16_t)netif->num)); + + /* add acd struct to list*/ + acd_add(netif, &autoip->acd, autoip_conflict_callback); + + /* In accordance to RFC3927 section 2.1: + * Keep using the same link local address as much as possible. + * Only when there is none or when there was a conflict, select a new one. + */ + if (!ip4_addr_islinklocal(&autoip->llipaddr)) { + autoip_create_addr(netif, &(autoip->llipaddr)); + } + autoip->state = AUTOIP_STATE_CHECKING; + acd_start(netif, &autoip->acd, autoip->llipaddr); + } else { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, + ("autoip_start(): already started on netif=%p %c%c%"U16_F"\n", + (void *)netif, netif->name[0], + netif->name[1], (u16_t)netif->num)); + } + + return result; +} + + +/** + * Handle a possible change in the network configuration: link up + * + * If there is an AutoIP address configured and AutoIP is not in cooperation + * with DHCP, start probing for previous address. + */ +void +autoip_network_changed_link_up(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + + if (autoip && (autoip->state != AUTOIP_STATE_OFF) && !LWIP_DHCP_AUTOIP_COOP) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_network_changed_link_up(): start acd\n")); + autoip->state = AUTOIP_STATE_CHECKING; + /* Start acd check again for the last used address */ + acd_start(netif, &autoip->acd, autoip->llipaddr); + } +} + +/** + * Handle a possible change in the network configuration: link down + * + * If there is an AutoIP address configured and AutoIP is in cooperation + * with DHCP, then stop the autoip module. When the link goes up, we do not want + * the autoip module to start again. DHCP will initiate autoip when needed. + */ +void +autoip_network_changed_link_down(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + + if (autoip && (autoip->state != AUTOIP_STATE_OFF) && LWIP_DHCP_AUTOIP_COOP) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_network_changed_link_down(): stop autoip\n")); + autoip_stop(netif); + } +} + +/** + * @ingroup autoip + * Stop AutoIP client + * + * @param netif network interface on which stop the AutoIP client + */ +err_t +autoip_stop(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + + LWIP_ASSERT_CORE_LOCKED(); + if (autoip != NULL) { + autoip->state = AUTOIP_STATE_OFF; + if (ip4_addr_islinklocal(netif_ip4_addr(netif))) { + netif_set_addr(netif, IP4_ADDR_ANY4, IP4_ADDR_ANY4, IP4_ADDR_ANY4); + } + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,("autoip_stop()\n")); + } + return ERR_OK; +} + +/** check if AutoIP supplied netif->ip_addr + * + * @param netif the netif to check + * @return 1 if AutoIP supplied netif->ip_addr (state BOUND), + * 0 otherwise + */ +u8_t +autoip_supplied_address(struct netif *netif) +{ + struct autoip *autoip = netif_autoip_data(netif); + return (autoip != NULL) + && (ip4_addr_eq(netif_ip4_addr(netif), &(autoip->llipaddr))) + && (autoip->state == AUTOIP_STATE_BOUND); +} + +u8_t +autoip_accept_packet(struct netif *netif, const ip4_addr_t *addr) +{ + struct autoip *autoip = netif_autoip_data(netif); + return (autoip != NULL) + && (ip4_addr_eq(addr, &(autoip->llipaddr))) + && (autoip->state == AUTOIP_STATE_BOUND); +} + +#endif /* LWIP_IPV4 && LWIP_AUTOIP */ |