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-rw-r--r--staging/lookupdev.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/staging/lookupdev.c b/staging/lookupdev.c
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+/*
+ * Mausezahn - A fast versatile traffic generator
+ * Copyright (C) 2008-2010 Herbert Haas
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, see http://www.gnu.org/licenses/gpl-2.0.html
+ *
+*/
+
+
+
+
+#include "mz.h"
+#include "mops.h"
+
+#include <netpacket/packet.h>
+#include <netinet/ether.h>
+
+
+// PURPOSE: Find usable network devices
+//
+// NOTE:
+//
+// 1. Ignores devices without IP address
+// 2. Ignores loopback (etc)
+//
+// RETURN VALUES:
+//
+// 0 if usable device found (device_list[] and tx.device set)
+// 1 if no usable device found
+//
+int lookupdev()
+{
+ // char *tx.device is global, see as.h
+
+ char
+ ipaddress[IPADDRSIZE+1],
+ errbuf[PCAP_ERRBUF_SIZE];
+
+ pcap_if_t
+ *alldevs,
+ *index = NULL;
+
+ pcap_addr_t *pcap_addr;
+
+ int i=0;
+
+
+ // FIRST get a list of all available devices
+ //
+ if (pcap_findalldevs(&alldevs, errbuf) == -1)
+ {
+ fprintf(stderr," mz: %s\n",errbuf);
+ return 1;
+ }
+
+ index = (pcap_if_t *) alldevs;
+
+ while (index)
+ {
+ if (index->addresses)
+ {
+ pcap_addr = index->addresses;
+ while(pcap_addr)
+ {
+ if (pcap_addr->addr && (pcap_addr->addr->sa_family==AF_INET))
+ {
+ if (inet_ntop(pcap_addr->addr->sa_family,
+ (void *)&pcap_addr->addr->sa_data[2],
+ ipaddress,
+ IPADDRSIZE))
+ {
+ if (verbose)
+ {
+ fprintf(stderr," mz: device %s got assigned %s ",
+ index->name, ipaddress);
+ }
+
+ if (strncmp(ipaddress, "127", 3)==0)
+ {
+ if (verbose) fprintf(stderr, "(loopback)\n");
+ strncpy(device_list[i].dev, index->name, 9);
+ strncpy(device_list[i].ip_str, ipaddress, IPADDRSIZE);
+ device_list[i].phy=0;
+ get_if_addr(index->name, device_list[i].ip, device_list[i].mac);
+ get_if_addr(index->name, device_list[i].ip_mops, device_list[i].mac_mops);
+ i++;
+ }
+ else if (strncmp(ipaddress, "169.254", 7)==0)
+ {
+ if (verbose) fprintf(stderr, "but IGNORED (cause: host-scope address)\n");
+ }
+ else // FOUND VALID INTERFACE
+ {
+ if (verbose) fprintf(stderr, "and is a possible candidate.\n");
+ strncpy(device_list[i].dev, index->name, 9);
+ strncpy(device_list[i].ip_str, ipaddress, IPADDRSIZE);
+ device_list[i].phy=1;
+ get_if_addr(index->name, device_list[i].ip, device_list[i].mac);
+ get_if_addr(index->name, device_list[i].ip_mops, device_list[i].mac_mops);
+ i++;
+ }
+
+ // Select only interfaces with IP addresses
+ // but avoid those that start with 127 or 169.254
+ // Put the remaining on a list. If this list has more than one entry
+ // ask the user which interface to listen to.
+ }
+ else
+ {
+ return 1;
+ }
+ }
+ pcap_addr = pcap_addr->next;
+ } // closes while(pcap_addr)
+ }
+ index = index->next;
+ } // closes while (index)
+
+ device_list_entries = i;
+
+ /*
+ if (verbose)
+ {
+ for (i=0; i<device_list_entries; i++)
+ {
+ fprintf(stderr, " mz: Found device %s with IP %s\n", device_list[i].dev, device_list[i].ip_str);
+ }
+ }
+ */
+
+ // No device found:
+ if (device_list_entries==0) return 1;
+
+ // Else device found:
+ // initialize tx.device with first entry of the device_list
+ strncpy (tx.device, device_list[0].dev, 16);
+
+ return 0;
+}
+
+
+
+
+
+
+
+
+// Determines ip and mac address of specified interface 'ifname'
+// Caller must provide an unsigned char ip[4], mac[6]
+//
+int get_if_addr (char *ifname, u_int8_t *ip, u_int8_t *mac)
+{
+ int fd, i;
+ struct ifreq ifr;
+ struct sockaddr_in saddr;
+ u_int8_t *x;
+
+ ifr.ifr_addr.sa_family = AF_INET;
+ strncpy(ifr.ifr_name, ifname , IFNAMSIZ-1);
+
+ // we must open a socket to get the addresses
+ fd = socket(AF_INET, SOCK_DGRAM, 0);
+ if (fd == -1) return 1;
+
+ // get mac
+ ioctl(fd, SIOCGIFHWADDR, &ifr);
+ for (i=0; i<6; i++) mac[i]= (u_int8_t) ifr.ifr_hwaddr.sa_data[i];
+
+ // get IP
+ ioctl(fd, SIOCGIFADDR, &ifr);
+ saddr=*((struct sockaddr_in *)(&(ifr.ifr_addr)));
+ x = (u_int8_t*)&saddr.sin_addr;
+ ip[0]=*x; ip[1]=*(x+1); ip[2]=*(x+2); ip[3]=*(x+3);
+
+ close(fd);
+
+
+ return 0;
+}
+
+
+
+
+// For a given device name, find out the following parameters:
+//
+// - MTU
+// - Network
+// - Mask
+// - Default GW (IP)
+// - Default GW (MAC)
+// - Open packet socket (if not already done)
+//
+int get_dev_params (char *name)
+{
+ FILE *fd;
+
+ char f[10][16], line[256];
+ int in=0, nw=1, gw=2, mk=7; // default columns in /proc/net/route for interface, network, gateway, and mask.
+ unsigned int tmp[4], net[4]={0,0,0,0}, dgw[4], mask[4]={0,0,0,0};
+ int i=0, flag=0, nw_found=0, gw_found=0, devind=0, dev_found=0;
+
+ struct ifreq si;
+ struct sockaddr_ll psock;
+ int ps, index, mtu;
+ struct arp_table_struct *cur;
+ // 1. Check if device is already present in our device_list
+
+ for (i=0; i<device_list_entries; i++) {
+ if (strncmp(device_list[i].dev, name, 16)==0) {
+ devind=i;
+ dev_found=1;
+ break;
+ }
+ }
+ if (dev_found==0) return 1; // ERROR: device name not found !!!!
+
+
+
+ // 2. find network, gateway, and mask
+
+ fd = fopen("/proc/net/route", "r");
+ while (fgets(line, 255, fd)!=NULL) {
+ sscanf(line, " %s %s %s %s %s %s %s %s %s %s", f[0], f[1], f[2], f[3], f[4], f[5], f[6], f[7], f[8], f[9]);
+ if (!flag) { // find columns (we do NOT assume that the order of columns is the same everywhere)
+ for (i=0; i<10; i++) {
+ if (strncasecmp(f[i],"iface", 16)==0) in=i;
+ if (strncasecmp(f[i],"destination", 16)==0) nw=i;
+ if (strncasecmp(f[i],"gateway", 16)==0) gw=i;
+ if (strncasecmp(f[i],"mask", 16)==0) mk=i;
+ }
+ flag=1;
+ }
+
+ if (strncmp(f[in], name, 16)==0) { // interface found
+ // Determine network
+ if ((strncmp(f[nw],"00000000",8)!=0) && (strncmp(f[gw],"00000000",8)==0)) {
+ // ignore 169.254 and 127 networks
+ sscanf(f[nw],"%02x%02x%02x%02x",&tmp[3], &tmp[2], &tmp[1], &tmp[0]);
+ if ((tmp[0]!=127) && (tmp[0]!=169)) {
+ nw_found=1;
+ net[0]=tmp[0];
+ net[1]=tmp[1];
+ net[2]=tmp[2];
+ net[3]=tmp[3];
+ // also get mask for that network
+ sscanf(f[mk],"%02x%02x%02x%02x",&tmp[3], &tmp[2], &tmp[1], &tmp[0]);
+ mask[0]=tmp[0];
+ mask[1]=tmp[1];
+ mask[2]=tmp[2];
+ mask[3]=tmp[3];
+ }
+ }
+ // Determine gateway
+ if ((strncmp(f[nw],"00000000",8)==0) && (strncmp(f[gw],"00000000",8)!=0)) {
+ sscanf(f[gw],"%02x%02x%02x%02x",&dgw[3], &dgw[2], &dgw[1], &dgw[0]);
+ gw_found=1;
+ }
+ }
+ }
+
+ fclose(fd);
+
+
+ // 3. Get device index, determine MTU,
+ // and bind socket to device for later TX and RX
+
+ // if socket is already open, then close and re-open it!
+ if (device_list[devind].ps>=0) {
+ close(device_list[devind].ps);
+ device_list[devind].ps=-1;
+ }
+
+ if (device_list[devind].ps<0) {
+ ps = socket (PF_PACKET, SOCK_RAW, htons(ETH_P_IP)); //ETH_P_ALL, ETH_P_802_3);
+ if (ps<0) {
+ fprintf(stderr, " Warning: [lookupdev.c get_dev_params()] Cannot open socket!\n");
+ return 1;
+ }
+
+ // Get device index
+ strncpy(si.ifr_name, name, IFNAMSIZ);
+ if (ioctl(ps, SIOCGIFINDEX, &si)==-1) {
+ perror("ioctl");
+ close(ps);
+ return 1;
+ }
+ index=si.ifr_ifindex;
+
+ // Get MTU
+ if (ioctl(ps, SIOCGIFMTU, &si)==-1) {
+ perror("ioctl");
+ close(ps);
+ return 1;
+ }
+ mtu = si.ifr_mtu;
+
+ // ***** bind socket for later TX and RX ****
+ psock.sll_family = AF_PACKET; // evident
+ // psock.sll_protocol = 0; // unsigned short - Physical layer protocol
+ psock.sll_ifindex = index; // int - Interface number
+ psock.sll_hatype = 0; // unsigned short - Header type //ARPHRD_ETHER
+ psock.sll_pkttype = 0; // unsigned char - Packet type
+ psock.sll_halen = 6; // unsigned char - Length of address
+ bind(ps, (const struct sockaddr *) &psock, sizeof(psock)); // <= !!!
+ device_list[devind].ps = ps; // Note that close(ps) must be done upon termination
+ }
+
+ // Get MAC of default gateway
+ service_arp(name, device_list[devind].ip_gw, device_list[devind].mac_gw);
+
+ usleep(200); // this is a VERY short delay but it usually works in today's LANs
+ cur=device_list[devind].arp_table;
+ while(cur!=NULL) {
+ if ((cur->sip[0]==dgw[0]) &&
+ (cur->sip[1]==dgw[1]) &&
+ (cur->sip[2]==dgw[2]) &&
+ (cur->sip[3]==dgw[3])) { // entry found!
+ for (i=0; i<6; i++) {
+ device_list[devind].mac_gw[i] = cur->smac[i];
+ }
+ }
+ cur=cur->next;
+ }
+
+ // FINALLY: Copy findings in device_list
+
+ if (device_list[devind].phy) {
+ for (i=0; i<4; i++) {
+ device_list[devind].net[i] = net[i];
+ device_list[devind].mask[i] = mask[i];
+ device_list[devind].ip_gw[i] = dgw[i];
+ }
+ }
+ else {
+ for (i=0; i<4; i++) {
+ device_list[devind].net[i] = 0;
+ device_list[devind].mask[i] = 0;
+ device_list[devind].ip_gw[i] = 0;
+ }
+ }
+
+ device_list[devind].index = index;
+ device_list[devind].mtu = mtu;
+
+ return 0;
+}
+
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