X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=blobdiff_plain;f=geekos%2Fsrc%2Flwip%2Fcore%2Fipv4%2Fautoip.c;fp=geekos%2Fsrc%2Flwip%2Fcore%2Fipv4%2Fautoip.c;h=b3920f2ad7c0a7242598d7af93afd79e1098b8a8;hp=0000000000000000000000000000000000000000;hb=ddc16b0737cf58f7aa90a69c6652cdf4090aec51;hpb=626595465a2c6987606a6bc697df65130ad8c2d3 diff --git a/geekos/src/lwip/core/ipv4/autoip.c b/geekos/src/lwip/core/ipv4/autoip.c new file mode 100644 index 0000000..b3920f2 --- /dev/null +++ b/geekos/src/lwip/core/ipv4/autoip.c @@ -0,0 +1,432 @@ +/** + * @file + * AutoIP Automatic LinkLocal IP Configuration + * + */ + +/* + * + * Copyright (c) 2007 Dominik Spies + * 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 + * + * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform + * with RFC 3927. + * + * + * Please coordinate changes and requests with Dominik Spies + * + */ + +/******************************************************************************* + * USAGE: + * + * define LWIP_AUTOIP 1 in your lwipopts.h + * + * If you don't use tcpip.c (so, don't call, you don't call tcpip_init): + * - First, call autoip_init(). + * - call autoip_tmr() all AUTOIP_TMR_INTERVAL msces, + * that should be defined in autoip.h. + * I recommend a value of 100. The value must divide 1000 with a remainder almost 0. + * Possible values are 1000, 500, 333, 250, 200, 166, 142, 125, 111, 100 .... + * + * Without DHCP: + * - Call autoip_start() after netif_add(). + * + * With DHCP: + * - define LWIP_DHCP_AUTOIP_COOP 1 in your lwipopts.h. + * - Configure your DHCP Client. + * + */ + +#include "lwip/opt.h" + +#if 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 "netif/etharp.h" + +#include +#include + +/* Pseudo random macro based on netif informations. + * You could use "rand()" from the C Library if you define LWIP_AUTOIP_RAND in lwipopts.h */ +#ifndef LWIP_AUTOIP_RAND +#define LWIP_AUTOIP_RAND(netif) ( (((u32_t)((netif->hwaddr[5]) & 0xff) << 24) | \ + ((u32_t)((netif->hwaddr[3]) & 0xff) << 16) | \ + ((u32_t)((netif->hwaddr[2]) & 0xff) << 8) | \ + ((u32_t)((netif->hwaddr[4]) & 0xff))) + \ + (netif->autoip?netif->autoip->tried_llipaddr:0)) +#endif /* LWIP_AUTOIP_RAND */ + +/* static functions */ +static void autoip_handle_arp_conflict(struct netif *netif); + +/* creates random LL IP-Address for a network interface */ +static void autoip_create_rand_addr(struct netif *netif, struct ip_addr *RandomIPAddr); + +/* sends an ARP announce */ +static err_t autoip_arp_announce(struct netif *netif); + +/* configure interface for use with current LL IP-Address */ +static err_t autoip_bind(struct netif *netif); + +/** + * Initialize this module + */ +void +autoip_init(void) +{ + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | 3, ("autoip_init()\n")); +} + +/** + * Handle a IP address conflict after an ARP conflict detection + */ +static void +autoip_handle_arp_conflict(struct netif *netif) +{ + /* Somehow detect if we are defending or retreating */ + unsigned char defend = 1; /* tbd */ + + if(defend) { + if(netif->autoip->lastconflict > 0) { + /* retreat, there was a conflicting ARP in the last + * DEFEND_INTERVAL seconds + */ + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_handle_arp_conflict(): we are defending, but in DEFEND_INTERVAL, retreating\n")); + + /* TODO: close all TCP sessions */ + autoip_start(netif); + } else { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_handle_arp_conflict(): we are defend, send ARP Announce\n")); + autoip_arp_announce(netif); + netif->autoip->lastconflict = DEFEND_INTERVAL * AUTOIP_TICKS_PER_SECOND; + } + } else { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_handle_arp_conflict(): we do not defend, retreating\n")); + /* TODO: close all TCP sessions */ + 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 RandomIPAddr ip address to initialize + */ +static void +autoip_create_rand_addr(struct netif *netif, struct ip_addr *RandomIPAddr) +{ + /* 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 + */ + + RandomIPAddr->addr = (0xA9FE0100 + ((u32_t)(((u8_t)(netif->hwaddr[4])) | + ((u32_t)((u8_t)(netif->hwaddr[5]))) << 8)) + netif->autoip->tried_llipaddr); + + if (RandomIPAddr->addr>0xA9FEFEFF) { + RandomIPAddr->addr = (0xA9FE0100 + (RandomIPAddr->addr-0xA9FEFEFF)); + } + if (RandomIPAddr->addr<0xA9FE0100) { + RandomIPAddr->addr = (0xA9FEFEFF - (0xA9FE0100-RandomIPAddr->addr)); + } + RandomIPAddr->addr = htonl(RandomIPAddr->addr); + + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_create_rand_addr(): tried_llipaddr=%"U16_F", 0x%08"X32_F"\n", + (u16_t)(netif->autoip->tried_llipaddr), (u32_t)(RandomIPAddr->addr))); +} + +/** + * Sends an ARP announce from a network interface + * + * @param netif network interface used to send the announce + */ +static err_t +autoip_arp_announce(struct netif *netif) +{ + return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, ðbroadcast, + (struct eth_addr *)netif->hwaddr, &netif->autoip->llipaddr, ðzero, + &netif->autoip->llipaddr, ARP_REQUEST); +} + +/** + * 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; + struct ip_addr sn_mask, gw_addr; + + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | 3, + ("autoip_bind(netif=%p) %c%c%"U16_F" 0x%08"X32_F"\n", + (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num, autoip->llipaddr.addr)); + + IP4_ADDR(&sn_mask, 255, 255, 0, 0); + IP4_ADDR(&gw_addr, 0, 0, 0, 0); + + netif_set_ipaddr(netif, &autoip->llipaddr); + netif_set_netmask(netif, &sn_mask); + netif_set_gw(netif, &gw_addr); + + /* bring the interface up */ + netif_set_up(netif); + + return ERR_OK; +} + +/** + * 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; + err_t result = ERR_OK; + + if(netif_is_up(netif)) { + netif_set_down(netif); + } + + /* Set IP-Address, Netmask and Gateway to 0 to make sure that + * ARP Packets are formed correctly + */ + netif->ip_addr.addr = 0; + netif->netmask.addr = 0; + netif->gw.addr = 0; + + 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)); + if(autoip == NULL) { + /* no AutoIP client attached yet? */ + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_start(): starting new AUTOIP client\n")); + autoip = mem_malloc(sizeof(struct autoip)); + if(autoip == NULL) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_start(): could not allocate autoip\n")); + return ERR_MEM; + } + memset( autoip, 0, sizeof(struct autoip)); + /* store this AutoIP client in the netif */ + netif->autoip = autoip; + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_start(): allocated autoip")); + } else { + autoip->state = AUTOIP_STATE_OFF; + autoip->ttw = 0; + autoip->sent_num = 0; + memset(&autoip->llipaddr, 0, sizeof(struct ip_addr)); + autoip->lastconflict = 0; + } + + autoip_create_rand_addr(netif, &(autoip->llipaddr)); + autoip->tried_llipaddr++; + autoip->state = AUTOIP_STATE_PROBING; + autoip->sent_num = 0; + + /* time to wait to first probe, this is randomly + * choosen out of 0 to PROBE_WAIT seconds. + * compliant to RFC 3927 Section 2.2.1 + */ + autoip->ttw = (u16_t)(LWIP_AUTOIP_RAND(netif) % (PROBE_WAIT * AUTOIP_TICKS_PER_SECOND)); + + /* + * if we tried more then MAX_CONFLICTS we must limit our rate for + * accquiring and probing address + * compliant to RFC 3927 Section 2.2.1 + */ + + if(autoip->tried_llipaddr > MAX_CONFLICTS) { + autoip->ttw = RATE_LIMIT_INTERVAL * AUTOIP_TICKS_PER_SECOND; + } + + return result; +} + +/** + * Stop AutoIP client + * + * @param netif network interface on which stop the AutoIP client + */ +err_t +autoip_stop(struct netif *netif) +{ + netif->autoip->state = AUTOIP_STATE_OFF; + netif_set_down(netif); + return ERR_OK; +} + +/** + * Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds + */ +void +autoip_tmr() +{ + struct netif *netif = netif_list; + /* loop through netif's */ + while (netif != NULL) { + /* only act on AutoIP configured interfaces */ + if (netif->autoip != NULL) { + if(netif->autoip->lastconflict > 0) { + netif->autoip->lastconflict--; + } + + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, + ("autoip_tmr() AutoIP-State: %"U16_F", ttw=%"U16_F"\n", + (u16_t)(netif->autoip->state), netif->autoip->ttw)); + + switch(netif->autoip->state) { + case AUTOIP_STATE_PROBING: + if(netif->autoip->ttw > 0) { + netif->autoip->ttw--; + } else { + if(netif->autoip->sent_num == PROBE_NUM) { + netif->autoip->state = AUTOIP_STATE_ANNOUNCING; + netif->autoip->sent_num = 0; + netif->autoip->ttw = ANNOUNCE_WAIT * AUTOIP_TICKS_PER_SECOND; + } else { + etharp_request(netif, &(netif->autoip->llipaddr)); + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | 3, + ("autoip_tmr() PROBING Sent Probe\n")); + netif->autoip->sent_num++; + /* calculate time to wait to next probe */ + netif->autoip->ttw = (u16_t)((LWIP_AUTOIP_RAND(netif) % + ((PROBE_MAX - PROBE_MIN) * AUTOIP_TICKS_PER_SECOND) ) + + PROBE_MIN * AUTOIP_TICKS_PER_SECOND); + } + } + break; + + case AUTOIP_STATE_ANNOUNCING: + if(netif->autoip->ttw > 0) { + netif->autoip->ttw--; + } else { + if(netif->autoip->sent_num == 0) { + /* We are here the first time, so we waited ANNOUNCE_WAIT seconds + * Now we can bind to an IP address and use it + */ + autoip_bind(netif); + } + + if(netif->autoip->sent_num == ANNOUNCE_NUM) { + netif->autoip->state = AUTOIP_STATE_BOUND; + netif->autoip->sent_num = 0; + netif->autoip->ttw = 0; + } else { + autoip_arp_announce(netif); + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | 3, + ("autoip_tmr() ANNOUNCING Sent Announce\n")); + netif->autoip->sent_num++; + netif->autoip->ttw = ANNOUNCE_INTERVAL * AUTOIP_TICKS_PER_SECOND; + } + } + break; + } + } + /* proceed to next network interface */ + netif = netif->next; + } +} + +/** + * Handles every incoming ARP Packet, called by etharp_arp_input. + * + * @param netif network interface to use for autoip processing + * @param hdr Incoming ARP packet + */ +void +autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr) +{ + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | 3, ("autoip_arp_reply()\n")); + if ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) { + /* when ip.src == llipaddr && hw.src != netif->hwaddr + * + * when probing ip.dst == llipaddr && hw.src != netif->hwaddr + * we have a conflict and must solve it + */ + struct ip_addr sipaddr, dipaddr; + struct eth_addr netifaddr; + netifaddr.addr[0] = netif->hwaddr[0]; + netifaddr.addr[1] = netif->hwaddr[1]; + netifaddr.addr[2] = netif->hwaddr[2]; + netifaddr.addr[3] = netif->hwaddr[3]; + netifaddr.addr[4] = netif->hwaddr[4]; + netifaddr.addr[5] = netif->hwaddr[5]; + + /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without + * structure packing (not using structure copy which breaks strict-aliasing rules). + */ + MEMCPY(&sipaddr, &hdr->sipaddr, sizeof(sipaddr)); + MEMCPY(&dipaddr, &hdr->dipaddr, sizeof(dipaddr)); + + if ((netif->autoip->state == AUTOIP_STATE_PROBING) || + ((netif->autoip->state == AUTOIP_STATE_ANNOUNCING) && + (netif->autoip->sent_num == 0))) { + /* RFC 3927 Section 2.2.1: + * from beginning to after ANNOUNCE_WAIT + * seconds we have a conflict if + * ip.src == llipaddr OR + * ip.dst == llipaddr && hw.src != own hwaddr + */ + if ((ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr)) || + (ip_addr_cmp(&dipaddr, &netif->autoip->llipaddr) && + !eth_addr_cmp(&netifaddr, &hdr->shwaddr))) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_arp_reply(): Probe Conflict detected\n")); + autoip_start(netif); + } + } else { + /* RFC 3927 Section 2.5: + * in any state we have a conflict if + * ip.src == llipaddr && hw.src != own hwaddr + */ + if (ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr) && + !eth_addr_cmp(&netifaddr, &hdr->shwaddr)) { + LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, + ("autoip_arp_reply(): Conflicting ARP-Packet detected\n")); + autoip_handle_arp_conflict(netif); + } + } + } +} + +#endif /* LWIP_AUTOIP */