/* $Id: netdump.c,v 1.5 2001/09/19 06:15:22 m_sato Exp $ *//*  * netdump.c -- dump all packets received from specified interface * * this is test program for "linux packet interface"  *  * see packet(7) and netdevice(7) */#include <features.h>#include <stdio.h>#include <stdint.h>#include <string.h>#include <unistd.h>#include <asm/types.h>#include <sys/types.h>#include <linux/if_packet.h>#include <linux/if_ether.h> #include <linux/if_arcnet.h> #include <linux/version.h>#include <net/if.h>#include <net/if_arp.h>#include <sys/ioctl.h>#include <sys/socket.h>#include <sys/time.h>#include <signal.h>#define DEBUG printfvoid print_ethaddr(const u_char *p);void print_arcaddr(const u_char *p);void hexdump(unsigned char *buf, int nbytes);void sigint(int);char *interface = NULL;int pd = -1;int main(int argc, char **argv){	int c;	unsigned char buf[2048];	unsigned char *p;	struct sockaddr_ll sll;	int i;	struct ifreq ifr;	int ifindex;	struct sockaddr myaddr;	int addrlen;	for (;;) {		c = getopt(argc, argv, "i:");		switch (c) {		case 'i':			interface = strdup(optarg);			break;		case -1:			break;		default:			fprintf(stderr, "usage: rawsock -i interface\n");			exit(1);		}		if (c == -1)			break;	}	if (interface == NULL) {		fprintf(stderr, "usage: rawsock -i interface\n");		exit(1);	}	signal(SIGINT, sigint);		pd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));	if (pd == -1) {		perror("socket():");		exit(1);	}	DEBUG("get interface index: ");	/* get interface index number */	memset(&ifr, 0, sizeof(ifr));	strncpy(ifr.ifr_name, interface, IFNAMSIZ);	if (ioctl(pd, SIOCGIFINDEX, &ifr) == -1) {		perror("SIOCGIFINDEX");		exit(1);	}	ifindex = ifr.ifr_ifindex;	DEBUG("%d\n", ifindex);	/* get hardware address */	DEBUG("get hardware address: ");	memset(&ifr, 0, sizeof(ifr));	strncpy(ifr.ifr_name, interface, IFNAMSIZ);	if (ioctl(pd, SIOCGIFHWADDR, &ifr) == -1) {		perror("SIOCGIFINDEX");		exit(1);	}	myaddr = ifr.ifr_hwaddr;	switch (myaddr.sa_family) {	case ARPHRD_ARCNET:		addrlen = 1;		break;	case ARPHRD_ETHER:		addrlen = 6;		break;	default:		addrlen = sizeof(myaddr.sa_data);	}	DEBUG("family = %d, address = ", myaddr.sa_family);	p = myaddr.sa_data;	for (i = 0; i < addrlen - 1; i++)		DEBUG("%02x:", *p++);	DEBUG("%02x\n", *p);	DEBUG("set promiscous mode\n");	memset(&ifr, 0, sizeof(ifr));	strncpy(ifr.ifr_name, interface, IFNAMSIZ);	ioctl(pd,SIOCGIFFLAGS,&ifr);	ifr.ifr_flags|=IFF_PROMISC;	ioctl(pd,SIOCSIFFLAGS,&ifr);	DEBUG("bind to %s\n", interface);	/*	 * bind(2) uses only sll_protocol and sll_ifindex. see packet(7)	 */	memset(&sll, 0xff, sizeof(sll));	sll.sll_family = AF_PACKET;	/* allways AF_PACKET */	sll.sll_protocol = htons(ETH_P_ALL);	sll.sll_ifindex = ifindex;	if (bind(pd, (struct sockaddr *)&sll, sizeof sll) == -1) {		perror("bind():");		exit(1);	}	DEBUG("flush receive buffer\n");	/* 	 * flush all received packets. 	 *         * raw-socket receives packets from all interfaces,	 * while the socket is not binded to a interface         */	do {		fd_set fds;		struct timeval t;		FD_ZERO(&fds);			FD_SET(pd, &fds);		memset(&t, 0, sizeof(t));		i = select(FD_SETSIZE, &fds, NULL, NULL, &t);		if (i > 0)			recv(pd, buf, i, 0);	} while (i);	DEBUG("start receiving\n");	for (;;) {		i = recv(pd, buf, sizeof(buf), 0);		if (i < 0) {			perror("recv():");			exit(1);		}		if (i == 0)			continue;		switch (myaddr.sa_family) {		case ARPHRD_ETHER:			print_ethaddr(buf);			break;		case ARPHRD_ARCNET:			print_arcaddr(buf);			break;		}		hexdump(buf, i);	}	/* NOT REACHED */	exit(0);}void hexdump(unsigned char *p, int count){	int i, j;	for(i = 0; i < count; i += 16) {		printf("%04x : ", i);		for (j = 0; j < 16 && i + j < count; j++)			printf("%2.2x ", p[i + j]);		for (; j < 16; j++) {			printf("   ");		}		printf(": ");		for (j = 0; j < 16 && i + j < count; j++) {			char c = toascii(p[i + j]);			printf("%c", isalnum(c) ? c : '.');		}		printf("\n");	}}voidprint_ethaddr(p)	const u_char *p;{	int i;	struct ethhdr *eh;	eh = (struct ethhdr *)p;	for (i = 0; i < 5; ++i) 		printf("%02x:", (int)eh->h_source[i]);	printf("%02x -> ", (int)eh->h_source[i]);	for (i = 0; i < 5; ++i) 		printf("%02x:", (int)eh->h_dest[i]);	printf("%02x", (int)eh->h_dest[i]);	printf("\n");}voidprint_arcaddr(p)	const u_char *p; {	int i;#if LINUX_VERSION_CODE >= 0x020400	struct arc_hardware *ah;	ah = (struct arc_hardware *)p;	printf("%02x->%02x ", (int)ah->source, (int)ah->dest);	printf("length = %d\n",		(ah->offset[0] != 0) ? 256 - ah->offset[0] : 512 - ah->offset[1]);#else	struct archdr *ah;	ah = (struct archdr *)p;	printf("%02x->%02x ", (int)ah->source, (int)ah->destination);	printf("length = %d\n",		(ah->offset1 != 0) ? 256 - ah->offset1 : 512 - ah->offset2);#endif}voidsigint(signum)	int signum;{	struct ifreq ifr;	if (pd == -1)		return;	memset(&ifr, 0, sizeof(ifr));	strncpy(ifr.ifr_name, interface, IFNAMSIZ);	ioctl(pd, SIOCGIFFLAGS,&ifr);	ifr.ifr_flags &= ~IFF_PROMISC;	ioctl(pd, SIOCSIFFLAGS,&ifr);	close(pd);	exit(0);}