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/* |
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* Copyright (c) 2006 Christophe Fillot. |
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* E-mail: cf@utc.fr |
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* |
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* linux_eth.c: module used to send/receive Ethernet packets. |
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* |
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* Specific to the Linux operating system. |
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*/ |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <stdarg.h> |
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#include <unistd.h> |
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#include <errno.h> |
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#include <signal.h> |
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#include <fcntl.h> |
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#include <ctype.h> |
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#include <netdb.h> |
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#include <sys/time.h> |
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#include <sys/stat.h> |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <sys/wait.h> |
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#include <netinet/in.h> |
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#include <arpa/inet.h> |
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#include <pthread.h> |
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|
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#include <sys/ioctl.h> |
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#include <netinet/if_ether.h> |
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#include <linux/if.h> |
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#include <linux/if_packet.h> |
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|
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#include "linux_eth.h" |
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|
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/* Get interface index of specified device */ |
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int lnx_eth_get_dev_index(char *name) |
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{ |
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struct ifreq if_req; |
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int fd; |
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|
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/* Create dummy file descriptor */ |
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if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { |
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fprintf(stderr,"eth_get_dev_index: socket: %s\n",strerror(errno)); |
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return(-1); |
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} |
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|
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memset((void *)&if_req,0,sizeof(if_req)); |
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strcpy(if_req.ifr_name,name); |
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|
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if (ioctl(fd,SIOCGIFINDEX,&if_req) < 0) { |
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fprintf(stderr,"eth_get_dev_index: SIOCGIFINDEX: %s\n",strerror(errno)); |
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close(fd); |
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return(-1); |
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} |
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|
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close(fd); |
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return(if_req.ifr_ifindex); |
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} |
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|
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/* Initialize a new ethernet raw socket */ |
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int lnx_eth_init_socket(char *device) |
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{ |
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struct sockaddr_ll sa; |
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struct packet_mreq mreq; |
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int sck; |
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|
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if ((sck = socket(PF_PACKET,SOCK_RAW,htons(ETH_P_ALL))) == -1) { |
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fprintf(stderr,"eth_init_socket: socket: %s\n",strerror(errno)); |
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return(-1); |
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} |
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|
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memset(&sa,0,sizeof(struct sockaddr_ll)); |
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sa.sll_family = AF_PACKET; |
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sa.sll_protocol = htons(ETH_P_ALL); |
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sa.sll_hatype = ARPHRD_ETHER; |
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sa.sll_halen = ETH_ALEN; |
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sa.sll_ifindex = lnx_eth_get_dev_index(device); |
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|
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memset(&mreq,0,sizeof(mreq)); |
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mreq.mr_ifindex = sa.sll_ifindex; |
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mreq.mr_type = PACKET_MR_PROMISC; |
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|
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if (bind(sck,(struct sockaddr *)&sa,sizeof(struct sockaddr_ll)) == -1) { |
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fprintf(stderr,"eth_init_socket: bind: %s\n",strerror(errno)); |
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return(-1); |
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} |
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|
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if (setsockopt(sck,SOL_PACKET,PACKET_ADD_MEMBERSHIP, |
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&mreq,sizeof(mreq)) == -1) |
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{ |
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fprintf(stderr,"eth_init_socket: setsockopt: %s\n",strerror(errno)); |
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return(-1); |
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} |
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|
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return(sck); |
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} |
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|
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/* Send an ethernet frame */ |
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ssize_t lnx_eth_send(int sck,int dev_id,char *buffer,size_t len) |
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{ |
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struct sockaddr_ll sa; |
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|
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memset(&sa,0,sizeof(struct sockaddr_ll)); |
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sa.sll_family = AF_PACKET; |
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sa.sll_protocol = htons(ETH_P_ALL); |
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sa.sll_hatype = ARPHRD_ETHER; |
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sa.sll_halen = ETH_ALEN; |
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sa.sll_ifindex = dev_id; |
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|
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return(sendto(sck,buffer,len,0,(struct sockaddr *)&sa,sizeof(sa))); |
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} |
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|
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/* Receive an ethernet frame */ |
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ssize_t lnx_eth_recv(int sck,char *buffer,size_t len) |
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{ |
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return(recv(sck,buffer,len,0)); |
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} |