ipmroute.c revision 38c867d2a82d6f2b60450550fbaaadc5d9c77579
1aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger/* 2aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * ipmroute.c "ip mroute". 3aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * 4aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * This program is free software; you can redistribute it and/or 5aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * modify it under the terms of the GNU General Public License 6aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * as published by the Free Software Foundation; either version 7aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * 2 of the License, or (at your option) any later version. 8aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * 9aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger * 11aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger */ 12aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 13aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <stdio.h> 14aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <stdlib.h> 15aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <unistd.h> 16aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <syslog.h> 17aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <fcntl.h> 18aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <sys/ioctl.h> 19aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <sys/socket.h> 2003156410981dcf7330a33d573154ec4a9302f741osdl.org!shemminger#include <netinet/in.h> 2103156410981dcf7330a33d573154ec4a9302f741osdl.org!shemminger#include <arpa/inet.h> 2203156410981dcf7330a33d573154ec4a9302f741osdl.org!shemminger#include <string.h> 2303156410981dcf7330a33d573154ec4a9302f741osdl.org!shemminger 24aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <linux/netdevice.h> 25aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <linux/if.h> 26aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <linux/if_arp.h> 27aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include <linux/sockios.h> 28aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 29aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#include "utils.h" 30aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 31aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerchar filter_dev[16]; 32aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerint filter_family; 33aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 34aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerstatic void usage(void) __attribute__((noreturn)); 35aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 36aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerstatic void usage(void) 37aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 38aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(stderr, "Usage: ip mroute show [ PREFIX ] [ from PREFIX ] [ iif DEVICE ]\n"); 39aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#if 0 40aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(stderr, "Usage: ip mroute [ add | del ] DESTINATION from SOURCE [ iif DEVICE ] [ oif DEVICE ]\n"); 41aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#endif 42aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger exit(-1); 43aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} 44aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 4584616f8317554be7542b2e89b69f4129995cb03bshemmingerstatic char *viftable[32]; 46aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 47aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerstruct rtfilter 48aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 49aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger inet_prefix mdst; 50aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger inet_prefix msrc; 51aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} filter; 52aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 5384616f8317554be7542b2e89b69f4129995cb03bshemmingerstatic void read_viftable(void) 54aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 55aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char buf[256]; 56aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger FILE *fp = fopen("/proc/net/ip_mr_vif", "r"); 57aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 58aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (!fp) 59aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return; 60aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 6138c867d2a82d6f2b60450550fbaaadc5d9c77579Stephen Hemminger if (!fgets(buf, sizeof(buf), fp)) 6238c867d2a82d6f2b60450550fbaaadc5d9c77579Stephen Hemminger return; 63aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 64aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger while (fgets(buf, sizeof(buf), fp)) { 65aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger int vifi; 66aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char dev[256]; 67aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 68aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (sscanf(buf, "%d%s", &vifi, dev) < 2) 69aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 70ae665a522bd46bea44c5ea84c89c8b1731954170Stephen Hemminger 71aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (vifi<0 || vifi>31) 72aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 73aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 74aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger viftable[vifi] = strdup(dev); 75aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 76aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fclose(fp); 77aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} 78aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 7984616f8317554be7542b2e89b69f4129995cb03bshemmingerstatic void read_mroute_list(FILE *ofp) 80aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 81aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char buf[256]; 82aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger FILE *fp = fopen("/proc/net/ip_mr_cache", "r"); 83aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 84aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (!fp) 85aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return; 86aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 8738c867d2a82d6f2b60450550fbaaadc5d9c77579Stephen Hemminger if (!fgets(buf, sizeof(buf), fp)) 8838c867d2a82d6f2b60450550fbaaadc5d9c77579Stephen Hemminger return; 89aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 90aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger while (fgets(buf, sizeof(buf), fp)) { 91aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger inet_prefix maddr, msrc; 92aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger unsigned pkts, b, w; 93aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger int vifi; 94aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char oiflist[256]; 95aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char sbuf[256]; 96aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char mbuf[256]; 97aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char obuf[256]; 98aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 99aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger oiflist[0] = 0; 100080b3ad42820e002b91ab4e3ddb728d2c6763b58Mark Borst if (sscanf(buf, "%x%x%d%u%u%u %[^\n]", 101080b3ad42820e002b91ab4e3ddb728d2c6763b58Mark Borst maddr.data, msrc.data, &vifi, 102aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger &pkts, &b, &w, oiflist) < 6) 103aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 104aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 105aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (vifi!=-1 && (vifi < 0 || vifi>31)) 106aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 107aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 108aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (filter_dev[0] && (vifi<0 || strcmp(filter_dev, viftable[vifi]))) 109aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 110aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (filter.mdst.family && inet_addr_match(&maddr, &filter.mdst, filter.mdst.bitlen)) 111aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 112aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (filter.msrc.family && inet_addr_match(&msrc, &filter.msrc, filter.msrc.bitlen)) 113aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 114aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 115ae665a522bd46bea44c5ea84c89c8b1731954170Stephen Hemminger snprintf(obuf, sizeof(obuf), "(%s, %s)", 116aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger format_host(AF_INET, 4, &msrc.data[0], sbuf, sizeof(sbuf)), 117aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger format_host(AF_INET, 4, &maddr.data[0], mbuf, sizeof(mbuf))); 118aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 119aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "%-32s Iif: ", obuf); 120aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 121aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (vifi == -1) 122aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "unresolved "); 123aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger else 124aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "%-10s ", viftable[vifi]); 125aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 126aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (oiflist[0]) { 127aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char *next = NULL; 128aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger char *p = oiflist; 129aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger int ovifi, ottl; 130aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 131aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "Oifs: "); 132aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 133aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger while (p) { 134aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger next = strchr(p, ' '); 135aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (next) { 136aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger *next = 0; 137aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger next++; 138aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 139aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (sscanf(p, "%d:%d", &ovifi, &ottl)<2) { 140aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger p = next; 141aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger continue; 142aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 143aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger p = next; 144aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 145aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "%s", viftable[ovifi]); 146aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (ottl>1) 147aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "(ttl %d) ", ovifi); 148aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger else 149aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, " "); 150aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 151aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 152aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 153aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (show_stats && b) { 154aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "%s %u packets, %u bytes", _SL_, pkts, b); 155aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (w) 156aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, ", %u arrived on wrong iif.", w); 157aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 158aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(ofp, "\n"); 159aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 160aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fclose(fp); 161aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} 162aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 163aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 164aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerstatic int mroute_list(int argc, char **argv) 165aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 166aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger while (argc > 0) { 167aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (strcmp(*argv, "iif") == 0) { 168aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger NEXT_ARG(); 169aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger strncpy(filter_dev, *argv, sizeof(filter_dev)-1); 170aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } else if (matches(*argv, "from") == 0) { 171aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger NEXT_ARG(); 172aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger get_prefix(&filter.msrc, *argv, AF_INET); 173aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } else { 174aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (strcmp(*argv, "to") == 0) { 175aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger NEXT_ARG(); 176aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 177aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "help") == 0) 178aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger usage(); 179aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger get_prefix(&filter.mdst, *argv, AF_INET); 180aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 181aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger argv++; argc--; 182aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger } 183aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 184aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger read_viftable(); 185aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger read_mroute_list(stdout); 186aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return 0; 187aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} 188aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger 189aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemmingerint do_multiroute(int argc, char **argv) 190aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger{ 191aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (argc < 1) 192aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return mroute_list(0, NULL); 193aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#if 0 194aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "add") == 0) 195aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return mroute_modify(RTM_NEWADDR, argc-1, argv+1); 196aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "delete") == 0) 197aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return mroute_modify(RTM_DELADDR, argc-1, argv+1); 198aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "get") == 0) 199aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return mroute_get(argc-1, argv+1); 200aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger#endif 201aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "list") == 0 || matches(*argv, "show") == 0 202aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger || matches(*argv, "lst") == 0) 203aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger return mroute_list(argc-1, argv+1); 204aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger if (matches(*argv, "help") == 0) 205aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger usage(); 206aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger fprintf(stderr, "Command \"%s\" is unknown, try \"ip mroute help\".\n", *argv); 207aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger exit(-1); 208aba5acdfdb347d2c21fc67d613d83d4430ca3937osdl.org!shemminger} 209