838 lines
17 KiB
C
838 lines
17 KiB
C
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/*
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* arpd.c ARP helper daemon.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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*/
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#include <stdio.h>
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#include <syslog.h>
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#include <malloc.h>
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#include <string.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <netdb.h>
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#include <db_185.h>
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#include <sys/ioctl.h>
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#include <sys/poll.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <sys/uio.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <time.h>
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#include <signal.h>
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#include <linux/if.h>
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#include <linux/if_ether.h>
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#include <linux/if_arp.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <linux/if_packet.h>
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#include <linux/filter.h>
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#include "libnetlink.h"
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#include "utils.h"
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#include "rt_names.h"
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DB *dbase;
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char *dbname = "/var/lib/arpd/arpd.db";
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int ifnum;
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int *ifvec;
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char **ifnames;
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struct dbkey {
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__u32 iface;
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__u32 addr;
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};
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#define IS_NEG(x) (((__u8 *)(x))[0] == 0xFF)
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#define NEG_TIME(x) (((x)[2]<<24)|((x)[3]<<16)|((x)[4]<<8)|(x)[5])
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#define NEG_AGE(x) ((__u32)time(NULL) - NEG_TIME((__u8 *)x))
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#define NEG_VALID(x) (NEG_AGE(x) < negative_timeout)
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#define NEG_CNT(x) (((__u8 *)(x))[1])
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struct rtnl_handle rth;
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struct pollfd pset[2];
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int udp_sock = -1;
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volatile int do_exit;
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volatile int do_sync;
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volatile int do_stats;
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struct {
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unsigned long arp_new;
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unsigned long arp_change;
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unsigned long app_recv;
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unsigned long app_success;
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unsigned long app_bad;
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unsigned long app_neg;
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unsigned long app_suppressed;
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unsigned long kern_neg;
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unsigned long kern_new;
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unsigned long kern_change;
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unsigned long probes_sent;
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unsigned long probes_suppressed;
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} stats;
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int active_probing;
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int negative_timeout = 60;
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int no_kernel_broadcasts;
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int broadcast_rate = 1000;
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int broadcast_burst = 3000;
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int poll_timeout = 30000;
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static void usage(void)
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{
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fprintf(stderr,
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"Usage: arpd [ -lkh? ] [ -a N ] [ -b dbase ] [ -B number ] [ -f file ] [ -n time ] [-p interval ] [ -R rate ] [ interfaces ]\n");
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exit(1);
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}
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static int handle_if(int ifindex)
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{
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int i;
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if (ifnum == 0)
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return 1;
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for (i = 0; i < ifnum; i++)
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if (ifvec[i] == ifindex)
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return 1;
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return 0;
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}
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int sysctl_adjusted;
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static void do_sysctl_adjustments(void)
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{
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int i;
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if (!ifnum)
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return;
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for (i = 0; i < ifnum; i++) {
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char buf[128];
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FILE *fp;
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if (active_probing) {
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sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/mcast_solicit", ifnames[i]);
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if ((fp = fopen(buf, "w")) != NULL) {
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if (no_kernel_broadcasts)
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strcpy(buf, "0\n");
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else
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sprintf(buf, "%d\n", active_probing >= 2 ? 1 : 3-active_probing);
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fputs(buf, fp);
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fclose(fp);
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}
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}
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sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/app_solicit", ifnames[i]);
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if ((fp = fopen(buf, "w")) != NULL) {
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sprintf(buf, "%d\n", active_probing <= 1 ? 1 : active_probing);
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fputs(buf, fp);
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fclose(fp);
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}
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}
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sysctl_adjusted = 1;
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}
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static void undo_sysctl_adjustments(void)
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{
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int i;
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if (!sysctl_adjusted)
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return;
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for (i = 0; i < ifnum; i++) {
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char buf[128];
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FILE *fp;
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if (active_probing) {
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sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/mcast_solicit", ifnames[i]);
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if ((fp = fopen(buf, "w")) != NULL) {
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strcpy(buf, "3\n");
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fputs(buf, fp);
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fclose(fp);
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}
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}
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sprintf(buf, "/proc/sys/net/ipv4/neigh/%s/app_solicit", ifnames[i]);
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if ((fp = fopen(buf, "w")) != NULL) {
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strcpy(buf, "0\n");
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fputs(buf, fp);
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fclose(fp);
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}
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}
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sysctl_adjusted = 0;
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}
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static int send_probe(int ifindex, __u32 addr)
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{
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struct ifreq ifr = { .ifr_ifindex = ifindex };
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struct sockaddr_in dst = {
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.sin_family = AF_INET,
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.sin_port = htons(1025),
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.sin_addr.s_addr = addr,
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};
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socklen_t len;
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unsigned char buf[256];
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struct arphdr *ah = (struct arphdr *)buf;
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unsigned char *p = (unsigned char *)(ah+1);
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struct sockaddr_ll sll = {
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.sll_family = AF_PACKET,
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.sll_ifindex = ifindex,
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.sll_protocol = htons(ETH_P_ARP),
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};
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if (ioctl(udp_sock, SIOCGIFNAME, &ifr))
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return -1;
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if (ioctl(udp_sock, SIOCGIFHWADDR, &ifr))
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return -1;
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if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER)
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return -1;
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if (setsockopt(udp_sock, SOL_SOCKET, SO_BINDTODEVICE, ifr.ifr_name, strlen(ifr.ifr_name)+1) < 0)
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return -1;
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if (connect(udp_sock, (struct sockaddr *)&dst, sizeof(dst)) < 0)
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return -1;
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len = sizeof(dst);
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if (getsockname(udp_sock, (struct sockaddr *)&dst, &len) < 0)
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return -1;
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ah->ar_hrd = htons(ifr.ifr_hwaddr.sa_family);
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ah->ar_pro = htons(ETH_P_IP);
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ah->ar_hln = 6;
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ah->ar_pln = 4;
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ah->ar_op = htons(ARPOP_REQUEST);
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memcpy(p, ifr.ifr_hwaddr.sa_data, ah->ar_hln);
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p += ah->ar_hln;
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memcpy(p, &dst.sin_addr, 4);
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p += 4;
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memset(sll.sll_addr, 0xFF, sizeof(sll.sll_addr));
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memcpy(p, &sll.sll_addr, ah->ar_hln);
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p += ah->ar_hln;
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memcpy(p, &addr, 4);
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p += 4;
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if (sendto(pset[0].fd, buf, p-buf, 0, (struct sockaddr *)&sll, sizeof(sll)) < 0)
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return -1;
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stats.probes_sent++;
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return 0;
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}
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/* Be very tough on sending probes: 1 per second with burst of 3. */
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static int queue_active_probe(int ifindex, __u32 addr)
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{
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static struct timeval prev;
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static int buckets;
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struct timeval now;
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gettimeofday(&now, NULL);
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if (prev.tv_sec) {
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int diff = (now.tv_sec-prev.tv_sec)*1000+(now.tv_usec-prev.tv_usec)/1000;
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buckets += diff;
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} else {
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buckets = broadcast_burst;
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}
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if (buckets > broadcast_burst)
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buckets = broadcast_burst;
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if (buckets >= broadcast_rate && !send_probe(ifindex, addr)) {
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buckets -= broadcast_rate;
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prev = now;
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return 0;
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}
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stats.probes_suppressed++;
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return -1;
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}
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static int respond_to_kernel(int ifindex, __u32 addr, char *lla, int llalen)
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{
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struct {
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struct nlmsghdr n;
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struct ndmsg ndm;
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char buf[256];
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} req = {
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.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
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.n.nlmsg_flags = NLM_F_REQUEST,
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.n.nlmsg_type = RTM_NEWNEIGH,
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.ndm.ndm_family = AF_INET,
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.ndm.ndm_state = NUD_STALE,
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.ndm.ndm_ifindex = ifindex,
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.ndm.ndm_type = RTN_UNICAST,
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};
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addattr_l(&req.n, sizeof(req), NDA_DST, &addr, 4);
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addattr_l(&req.n, sizeof(req), NDA_LLADDR, lla, llalen);
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return rtnl_send(&rth, &req, req.n.nlmsg_len) <= 0;
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}
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static void prepare_neg_entry(__u8 *ndata, __u32 stamp)
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{
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ndata[0] = 0xFF;
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ndata[1] = 0;
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ndata[2] = stamp>>24;
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ndata[3] = stamp>>16;
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ndata[4] = stamp>>8;
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ndata[5] = stamp;
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}
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static int do_one_request(struct nlmsghdr *n)
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{
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struct ndmsg *ndm = NLMSG_DATA(n);
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int len = n->nlmsg_len;
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struct rtattr *tb[NDA_MAX+1];
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struct dbkey key;
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DBT dbkey, dbdat;
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int do_acct = 0;
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if (n->nlmsg_type == NLMSG_DONE) {
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dbase->sync(dbase, 0);
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/* Now we have at least mirror of kernel db, so that
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* may start real resolution.
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*/
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do_sysctl_adjustments();
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return 0;
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}
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if (n->nlmsg_type != RTM_GETNEIGH && n->nlmsg_type != RTM_NEWNEIGH)
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return 0;
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len -= NLMSG_LENGTH(sizeof(*ndm));
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if (len < 0)
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return -1;
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if (ndm->ndm_family != AF_INET ||
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(ifnum && !handle_if(ndm->ndm_ifindex)) ||
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ndm->ndm_flags ||
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ndm->ndm_type != RTN_UNICAST ||
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!(ndm->ndm_state&~NUD_NOARP))
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return 0;
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parse_rtattr(tb, NDA_MAX, NDA_RTA(ndm), len);
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if (!tb[NDA_DST])
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return 0;
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key.iface = ndm->ndm_ifindex;
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memcpy(&key.addr, RTA_DATA(tb[NDA_DST]), 4);
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dbkey.data = &key;
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dbkey.size = sizeof(key);
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if (dbase->get(dbase, &dbkey, &dbdat, 0) != 0) {
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dbdat.data = 0;
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dbdat.size = 0;
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}
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if (n->nlmsg_type == RTM_GETNEIGH) {
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if (!(n->nlmsg_flags&NLM_F_REQUEST))
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return 0;
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if (!(ndm->ndm_state&(NUD_PROBE|NUD_INCOMPLETE))) {
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stats.app_bad++;
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return 0;
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}
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if (ndm->ndm_state&NUD_PROBE) {
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/* If we get this, kernel still has some valid
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* address, but unicast probing failed and host
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* is either dead or changed its mac address.
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* Kernel is going to initiate broadcast resolution.
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* OK, we invalidate our information as well.
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*/
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if (dbdat.data && !IS_NEG(dbdat.data))
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stats.app_neg++;
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dbase->del(dbase, &dbkey, 0);
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} else {
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/* If we get this kernel does not have any information.
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* If we have something tell this to kernel. */
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stats.app_recv++;
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if (dbdat.data && !IS_NEG(dbdat.data)) {
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stats.app_success++;
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respond_to_kernel(key.iface, key.addr, dbdat.data, dbdat.size);
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return 0;
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}
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/* Sheeit! We have nothing to tell. */
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/* If we have recent negative entry, be silent. */
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if (dbdat.data && NEG_VALID(dbdat.data)) {
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if (NEG_CNT(dbdat.data) >= active_probing) {
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stats.app_suppressed++;
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return 0;
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}
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do_acct = 1;
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}
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}
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if (active_probing &&
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queue_active_probe(ndm->ndm_ifindex, key.addr) == 0 &&
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do_acct) {
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NEG_CNT(dbdat.data)++;
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dbase->put(dbase, &dbkey, &dbdat, 0);
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}
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} else if (n->nlmsg_type == RTM_NEWNEIGH) {
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if (n->nlmsg_flags&NLM_F_REQUEST)
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return 0;
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if (ndm->ndm_state&NUD_FAILED) {
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/* Kernel was not able to resolve. Host is dead.
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* Create negative entry if it is not present
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* or renew it if it is too old. */
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if (!dbdat.data ||
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!IS_NEG(dbdat.data) ||
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!NEG_VALID(dbdat.data)) {
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__u8 ndata[6];
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stats.kern_neg++;
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prepare_neg_entry(ndata, time(NULL));
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dbdat.data = ndata;
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dbdat.size = sizeof(ndata);
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dbase->put(dbase, &dbkey, &dbdat, 0);
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}
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} else if (tb[NDA_LLADDR]) {
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if (dbdat.data && !IS_NEG(dbdat.data)) {
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if (memcmp(RTA_DATA(tb[NDA_LLADDR]), dbdat.data, dbdat.size) == 0)
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return 0;
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stats.kern_change++;
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} else {
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stats.kern_new++;
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}
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dbdat.data = RTA_DATA(tb[NDA_LLADDR]);
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dbdat.size = RTA_PAYLOAD(tb[NDA_LLADDR]);
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dbase->put(dbase, &dbkey, &dbdat, 0);
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}
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}
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return 0;
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}
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static void load_initial_table(void)
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{
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if (rtnl_wilddump_request(&rth, AF_INET, RTM_GETNEIGH) < 0) {
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perror("dump request failed");
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exit(1);
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}
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}
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||
|
|
||
|
static void get_kern_msg(void)
|
||
|
{
|
||
|
int status;
|
||
|
struct nlmsghdr *h;
|
||
|
struct sockaddr_nl nladdr = {};
|
||
|
struct iovec iov;
|
||
|
char buf[8192];
|
||
|
struct msghdr msg = {
|
||
|
(void *)&nladdr, sizeof(nladdr),
|
||
|
&iov, 1,
|
||
|
NULL, 0,
|
||
|
0
|
||
|
};
|
||
|
|
||
|
iov.iov_base = buf;
|
||
|
iov.iov_len = sizeof(buf);
|
||
|
|
||
|
status = recvmsg(rth.fd, &msg, MSG_DONTWAIT);
|
||
|
|
||
|
if (status <= 0)
|
||
|
return;
|
||
|
|
||
|
if (msg.msg_namelen != sizeof(nladdr))
|
||
|
return;
|
||
|
|
||
|
if (nladdr.nl_pid)
|
||
|
return;
|
||
|
|
||
|
for (h = (struct nlmsghdr *)buf; status >= sizeof(*h); ) {
|
||
|
int len = h->nlmsg_len;
|
||
|
int l = len - sizeof(*h);
|
||
|
|
||
|
if (l < 0 || len > status)
|
||
|
return;
|
||
|
|
||
|
if (do_one_request(h) < 0)
|
||
|
return;
|
||
|
|
||
|
status -= NLMSG_ALIGN(len);
|
||
|
h = (struct nlmsghdr *)((char *)h + NLMSG_ALIGN(len));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Receive gratuitous ARP messages and store them, that's all. */
|
||
|
static void get_arp_pkt(void)
|
||
|
{
|
||
|
unsigned char buf[1024];
|
||
|
struct sockaddr_ll sll;
|
||
|
socklen_t sll_len = sizeof(sll);
|
||
|
struct arphdr *a = (struct arphdr *)buf;
|
||
|
struct dbkey key;
|
||
|
DBT dbkey, dbdat;
|
||
|
int n;
|
||
|
|
||
|
n = recvfrom(pset[0].fd, buf, sizeof(buf), MSG_DONTWAIT,
|
||
|
(struct sockaddr *)&sll, &sll_len);
|
||
|
if (n < 0) {
|
||
|
if (errno != EINTR && errno != EAGAIN)
|
||
|
syslog(LOG_ERR, "recvfrom: %m");
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
if (ifnum && !handle_if(sll.sll_ifindex))
|
||
|
return;
|
||
|
|
||
|
/* Sanity checks */
|
||
|
|
||
|
if (n < sizeof(*a) ||
|
||
|
(a->ar_op != htons(ARPOP_REQUEST) &&
|
||
|
a->ar_op != htons(ARPOP_REPLY)) ||
|
||
|
a->ar_pln != 4 ||
|
||
|
a->ar_pro != htons(ETH_P_IP) ||
|
||
|
a->ar_hln != sll.sll_halen ||
|
||
|
sizeof(*a) + 2*4 + 2*a->ar_hln > n)
|
||
|
return;
|
||
|
|
||
|
key.iface = sll.sll_ifindex;
|
||
|
memcpy(&key.addr, (char *)(a+1) + a->ar_hln, 4);
|
||
|
|
||
|
/* DAD message, ignore. */
|
||
|
if (key.addr == 0)
|
||
|
return;
|
||
|
|
||
|
dbkey.data = &key;
|
||
|
dbkey.size = sizeof(key);
|
||
|
|
||
|
if (dbase->get(dbase, &dbkey, &dbdat, 0) == 0 && !IS_NEG(dbdat.data)) {
|
||
|
if (memcmp(dbdat.data, a+1, dbdat.size) == 0)
|
||
|
return;
|
||
|
stats.arp_change++;
|
||
|
} else {
|
||
|
stats.arp_new++;
|
||
|
}
|
||
|
|
||
|
dbdat.data = a+1;
|
||
|
dbdat.size = a->ar_hln;
|
||
|
dbase->put(dbase, &dbkey, &dbdat, 0);
|
||
|
}
|
||
|
|
||
|
static void catch_signal(int sig, void (*handler)(int))
|
||
|
{
|
||
|
struct sigaction sa = { .sa_handler = handler };
|
||
|
|
||
|
#ifdef SA_INTERRUPT
|
||
|
sa.sa_flags = SA_INTERRUPT;
|
||
|
#endif
|
||
|
sigaction(sig, &sa, NULL);
|
||
|
}
|
||
|
|
||
|
#include <setjmp.h>
|
||
|
sigjmp_buf env;
|
||
|
volatile int in_poll;
|
||
|
|
||
|
static void sig_exit(int signo)
|
||
|
{
|
||
|
do_exit = 1;
|
||
|
if (in_poll)
|
||
|
siglongjmp(env, 1);
|
||
|
}
|
||
|
|
||
|
static void sig_sync(int signo)
|
||
|
{
|
||
|
do_sync = 1;
|
||
|
if (in_poll)
|
||
|
siglongjmp(env, 1);
|
||
|
}
|
||
|
|
||
|
static void sig_stats(int signo)
|
||
|
{
|
||
|
do_sync = 1;
|
||
|
do_stats = 1;
|
||
|
if (in_poll)
|
||
|
siglongjmp(env, 1);
|
||
|
}
|
||
|
|
||
|
static void send_stats(void)
|
||
|
{
|
||
|
syslog(LOG_INFO, "arp_rcv: n%lu c%lu app_rcv: tot %lu hits %lu bad %lu neg %lu sup %lu",
|
||
|
stats.arp_new, stats.arp_change,
|
||
|
|
||
|
stats.app_recv, stats.app_success,
|
||
|
stats.app_bad, stats.app_neg, stats.app_suppressed
|
||
|
);
|
||
|
syslog(LOG_INFO, "kern: n%lu c%lu neg %lu arp_send: %lu rlim %lu",
|
||
|
stats.kern_new, stats.kern_change, stats.kern_neg,
|
||
|
|
||
|
stats.probes_sent, stats.probes_suppressed
|
||
|
);
|
||
|
do_stats = 0;
|
||
|
}
|
||
|
|
||
|
|
||
|
int main(int argc, char **argv)
|
||
|
{
|
||
|
int opt;
|
||
|
int do_list = 0;
|
||
|
char *do_load = NULL;
|
||
|
|
||
|
while ((opt = getopt(argc, argv, "h?b:lf:a:n:p:kR:B:")) != EOF) {
|
||
|
switch (opt) {
|
||
|
case 'b':
|
||
|
dbname = optarg;
|
||
|
break;
|
||
|
case 'f':
|
||
|
if (do_load) {
|
||
|
fprintf(stderr, "Duplicate option -f\n");
|
||
|
usage();
|
||
|
}
|
||
|
do_load = optarg;
|
||
|
break;
|
||
|
case 'l':
|
||
|
do_list = 1;
|
||
|
break;
|
||
|
case 'a':
|
||
|
active_probing = atoi(optarg);
|
||
|
break;
|
||
|
case 'n':
|
||
|
negative_timeout = atoi(optarg);
|
||
|
break;
|
||
|
case 'k':
|
||
|
no_kernel_broadcasts = 1;
|
||
|
break;
|
||
|
case 'p':
|
||
|
if ((poll_timeout = 1000 * strtod(optarg, NULL)) < 100) {
|
||
|
fprintf(stderr, "Invalid poll timeout\n");
|
||
|
exit(-1);
|
||
|
}
|
||
|
break;
|
||
|
case 'R':
|
||
|
if ((broadcast_rate = atoi(optarg)) <= 0 ||
|
||
|
(broadcast_rate = 1000/broadcast_rate) <= 0) {
|
||
|
fprintf(stderr, "Invalid ARP rate\n");
|
||
|
exit(-1);
|
||
|
}
|
||
|
break;
|
||
|
case 'B':
|
||
|
if ((broadcast_burst = atoi(optarg)) <= 0 ||
|
||
|
(broadcast_burst = 1000*broadcast_burst) <= 0) {
|
||
|
fprintf(stderr, "Invalid ARP burst\n");
|
||
|
exit(-1);
|
||
|
}
|
||
|
break;
|
||
|
case 'h':
|
||
|
case '?':
|
||
|
default:
|
||
|
usage();
|
||
|
}
|
||
|
}
|
||
|
argc -= optind;
|
||
|
argv += optind;
|
||
|
|
||
|
if (argc > 0) {
|
||
|
ifnum = argc;
|
||
|
ifnames = argv;
|
||
|
ifvec = malloc(argc*sizeof(int));
|
||
|
if (!ifvec) {
|
||
|
perror("malloc");
|
||
|
exit(-1);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if ((udp_sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
|
||
|
perror("socket");
|
||
|
exit(-1);
|
||
|
}
|
||
|
|
||
|
if (ifnum) {
|
||
|
int i;
|
||
|
struct ifreq ifr = {};
|
||
|
|
||
|
for (i = 0; i < ifnum; i++) {
|
||
|
if (get_ifname(ifr.ifr_name, ifnames[i]))
|
||
|
invarg("not a valid ifname", ifnames[i]);
|
||
|
if (ioctl(udp_sock, SIOCGIFINDEX, &ifr)) {
|
||
|
perror("ioctl(SIOCGIFINDEX)");
|
||
|
exit(-1);
|
||
|
}
|
||
|
ifvec[i] = ifr.ifr_ifindex;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
dbase = dbopen(dbname, O_CREAT|O_RDWR, 0644, DB_HASH, NULL);
|
||
|
if (dbase == NULL) {
|
||
|
perror("db_open");
|
||
|
exit(-1);
|
||
|
}
|
||
|
|
||
|
if (do_load) {
|
||
|
char buf[128];
|
||
|
FILE *fp;
|
||
|
struct dbkey k;
|
||
|
DBT dbkey, dbdat;
|
||
|
|
||
|
dbkey.data = &k;
|
||
|
dbkey.size = sizeof(k);
|
||
|
|
||
|
if (strcmp(do_load, "-") == 0 || strcmp(do_load, "--") == 0) {
|
||
|
fp = stdin;
|
||
|
} else if ((fp = fopen(do_load, "r")) == NULL) {
|
||
|
perror("fopen");
|
||
|
goto do_abort;
|
||
|
}
|
||
|
|
||
|
buf[sizeof(buf)-1] = 0;
|
||
|
while (fgets(buf, sizeof(buf), fp)) {
|
||
|
__u8 b1[6];
|
||
|
char ipbuf[128];
|
||
|
char macbuf[128];
|
||
|
|
||
|
if (buf[0] == '#')
|
||
|
continue;
|
||
|
|
||
|
if (sscanf(buf, "%u%s%s", &k.iface, ipbuf, macbuf) != 3) {
|
||
|
fprintf(stderr, "Wrong format of input file \"%s\"\n", do_load);
|
||
|
goto do_abort;
|
||
|
}
|
||
|
if (strncmp(macbuf, "FAILED:", 7) == 0)
|
||
|
continue;
|
||
|
if (!inet_aton(ipbuf, (struct in_addr *)&k.addr)) {
|
||
|
fprintf(stderr, "Invalid IP address: \"%s\"\n", ipbuf);
|
||
|
goto do_abort;
|
||
|
}
|
||
|
|
||
|
if (ll_addr_a2n((char *) b1, 6, macbuf) != 6)
|
||
|
goto do_abort;
|
||
|
dbdat.size = 6;
|
||
|
|
||
|
if (dbase->put(dbase, &dbkey, &dbdat, 0)) {
|
||
|
perror("hash->put");
|
||
|
goto do_abort;
|
||
|
}
|
||
|
}
|
||
|
dbase->sync(dbase, 0);
|
||
|
if (fp != stdin)
|
||
|
fclose(fp);
|
||
|
}
|
||
|
|
||
|
if (do_list) {
|
||
|
DBT dbkey, dbdat;
|
||
|
|
||
|
printf("%-8s %-15s %s\n", "#Ifindex", "IP", "MAC");
|
||
|
while (dbase->seq(dbase, &dbkey, &dbdat, R_NEXT) == 0) {
|
||
|
struct dbkey *key = dbkey.data;
|
||
|
|
||
|
if (handle_if(key->iface)) {
|
||
|
if (!IS_NEG(dbdat.data)) {
|
||
|
char b1[18];
|
||
|
|
||
|
printf("%-8d %-15s %s\n",
|
||
|
key->iface,
|
||
|
inet_ntoa(*(struct in_addr *)&key->addr),
|
||
|
ll_addr_n2a(dbdat.data, 6, ARPHRD_ETHER, b1, 18));
|
||
|
} else {
|
||
|
printf("%-8d %-15s FAILED: %dsec ago\n",
|
||
|
key->iface,
|
||
|
inet_ntoa(*(struct in_addr *)&key->addr),
|
||
|
NEG_AGE(dbdat.data));
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (do_load || do_list)
|
||
|
goto out;
|
||
|
|
||
|
pset[0].fd = socket(PF_PACKET, SOCK_DGRAM, 0);
|
||
|
if (pset[0].fd < 0) {
|
||
|
perror("socket");
|
||
|
exit(-1);
|
||
|
}
|
||
|
|
||
|
if (1) {
|
||
|
struct sockaddr_ll sll = {
|
||
|
.sll_family = AF_PACKET,
|
||
|
.sll_protocol = htons(ETH_P_ARP),
|
||
|
.sll_ifindex = (ifnum == 1 ? ifvec[0] : 0),
|
||
|
};
|
||
|
|
||
|
if (bind(pset[0].fd, (struct sockaddr *)&sll, sizeof(sll)) < 0) {
|
||
|
perror("bind");
|
||
|
goto do_abort;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (rtnl_open(&rth, RTMGRP_NEIGH) < 0) {
|
||
|
perror("rtnl_open");
|
||
|
goto do_abort;
|
||
|
}
|
||
|
pset[1].fd = rth.fd;
|
||
|
|
||
|
load_initial_table();
|
||
|
|
||
|
if (daemon(0, 0)) {
|
||
|
perror("arpd: daemon");
|
||
|
goto do_abort;
|
||
|
}
|
||
|
|
||
|
openlog("arpd", LOG_PID | LOG_CONS, LOG_DAEMON);
|
||
|
catch_signal(SIGINT, sig_exit);
|
||
|
catch_signal(SIGTERM, sig_exit);
|
||
|
catch_signal(SIGHUP, sig_sync);
|
||
|
catch_signal(SIGUSR1, sig_stats);
|
||
|
|
||
|
#define EVENTS (POLLIN|POLLPRI|POLLERR|POLLHUP)
|
||
|
pset[0].events = EVENTS;
|
||
|
pset[0].revents = 0;
|
||
|
pset[1].events = EVENTS;
|
||
|
pset[1].revents = 0;
|
||
|
|
||
|
sigsetjmp(env, 1);
|
||
|
|
||
|
for (;;) {
|
||
|
in_poll = 1;
|
||
|
|
||
|
if (do_exit)
|
||
|
break;
|
||
|
if (do_sync) {
|
||
|
in_poll = 0;
|
||
|
dbase->sync(dbase, 0);
|
||
|
do_sync = 0;
|
||
|
in_poll = 1;
|
||
|
}
|
||
|
if (do_stats)
|
||
|
send_stats();
|
||
|
if (poll(pset, 2, poll_timeout) > 0) {
|
||
|
in_poll = 0;
|
||
|
if (pset[0].revents&EVENTS)
|
||
|
get_arp_pkt();
|
||
|
if (pset[1].revents&EVENTS)
|
||
|
get_kern_msg();
|
||
|
} else {
|
||
|
do_sync = 1;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
undo_sysctl_adjustments();
|
||
|
out:
|
||
|
dbase->close(dbase);
|
||
|
exit(0);
|
||
|
|
||
|
do_abort:
|
||
|
dbase->close(dbase);
|
||
|
exit(-1);
|
||
|
}
|