New junkcode!

junkcode/swehack@gmail.com-snifstat/snifstat.c

+/* this application captures packets destined to and from 
+ * a specified host, it then tries to calculate in and out 
+ * traffic statistics and display it like ifstat 
+ * by nocturnal [at] swehack [dot] se */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+
+/* gethostbyname(3) */
+#include <netdb.h>
+
+/* networking(4) */
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <net/route.h>
+#include <net/if_dl.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netinet/if_ether.h>
+#include <ifaddrs.h>
+
+/* setitimer(2) */
+#include <sys/time.h>
+
+/* signal(3) */
+#include <signal.h>
+
+/* get_windowsize */
+#include <termios.h>
+#ifndef TIOCGWINSZ
+#include <sys/ioctl.h>
+#endif
+
+/* duh -lpcap */
+#include <pcap.h>
+
+#define APP_NAME	"snifstat"
+#define APP_VERSION	0.2
+
+unsigned int calc_traf_io(char *, struct ether_header *);
+int ethaddrsncmp(const char *, const char *, size_t);
+void reset_count(int);
+unsigned short get_windowsize(void);
+void usage(const char *);
+
+unsigned int reset = 0;
+
+int main(int argc, char **argv) {
+	char *ifname = NULL;
+	int argch;
+	unsigned int show_in_bits = 0;
+	char bits_prefix[] = "Kbps";
+	char bytes_prefix[] = "KB/s";
+	unsigned int max_iteration = 0;
+
+	char errbuf[PCAP_ERRBUF_SIZE];
+	pcap_t *pcap = NULL;
+	struct bpf_program filterd;
+	bpf_u_int32 netp, netmask;
+	char *filter = NULL;
+	const u_char *packet = NULL;
+	struct pcap_pkthdr header;
+	
+	unsigned char *ether_addrs = NULL;
+	struct ifaddrs *ifa = NULL;
+	struct sockaddr_dl *sdl = NULL;
+
+	struct itimerval itv, oitv;
+	struct itimerval *itvp = &itv;
+
+
+	struct ether_header *ethernet = NULL;
+	
+	unsigned int iteration = 0, total_iteration = 0;
+	double cur_in, cur_out;
+	unsigned short cur_ws = 0, new_ws, old_ws, ws_change;
+	unsigned int traf_io = 2;
+
+	unsigned int *resetp = &reset;
+
+	if(argc < 4) {
+		usage(argv[0]);
+		exit(-1);
+	}
+
+	while((argch = getopt(argc, argv, "i:bc:hv")) != -1) {
+		switch(argch) {
+			case 'i':
+				if(strlen(optarg) < 16) {
+					ifname = optarg;
+					optreset = 1;
+				} else {
+					usage(argv[0]);
+					exit(-1);
+				}
+				break;
+			case 'b':
+				show_in_bits = 1;
+				optreset = 1;
+				break;
+			case 'c':
+				max_iteration = (unsigned int)atoi(optarg);
+				break;
+			case 'h':
+				usage(argv[0]);
+				exit(-1);
+			case 'v': /* LOL WUT?! */
+				printf("%s v%.1f by nocturnal [at] swehack [dot] se\n", APP_NAME, APP_VERSION);
+				exit(-1);
+		}
+	}
+
+	if(argc - optind < 1) {
+		usage(argv[0]);
+		exit(-1);
+	}
+
+	filter = argv[optind];
+
+	if(pcap_lookupnet(ifname, &netp, &netmask, errbuf) == -1) {
+		fprintf(stderr, "pcap_lookupnet: %s\n", errbuf);
+		exit(-1);
+	}
+
+	if((pcap = pcap_open_live(ifname, 65535, 1, 10, errbuf)) == NULL) {
+		fprintf(stderr, "pcap_open_live: %s\n", errbuf);
+		exit(-1);
+	}
+
+	if(pcap_compile(pcap, &filterd, filter, 1, netmask) == -1) {
+		fprintf(stderr, "pcap_compile: %s\n", pcap_geterr(pcap));
+		exit(-1);
+	}
+
+	if(pcap_setfilter(pcap, &filterd) == -1) {
+		fprintf(stderr, "pcap_setfilter: %s\n", pcap_geterr(pcap));
+		exit(-1);
+	}
+
+	if(signal(SIGALRM, reset_count) == SIG_ERR) {
+		perror("signal: ");
+		exit(-1);
+	}
+
+	if(getifaddrs(&ifa) == -1) {
+		perror("getifaddrs: ");
+		exit(-1);
+	}
+
+	for(;ifa;ifa = ifa->ifa_next) {
+		if(strncmp(ifname, ifa->ifa_name, sizeof(ifa->ifa_name)) == 0) {
+			sdl = (struct sockaddr_dl *)ifa->ifa_addr;
+			if((ether_addrs = malloc(sdl->sdl_alen)) == NULL) {
+				perror("malloc: ");
+				exit(-1);
+			}
+			memcpy(ether_addrs, LLADDR(sdl), sdl->sdl_alen);
+			break;
+		}
+	}
+
+	timerclear(&itvp->it_interval);
+	itvp->it_value.tv_sec = 1;
+	itvp->it_value.tv_usec = 0;
+
+	while(1) {
+		*resetp = 0;
+
+		old_ws = cur_ws;
+		new_ws = get_windowsize();
+		if(new_ws != old_ws) {
+			cur_ws = new_ws;
+		}
+		ws_change = cur_ws-2;
+
+		if(setitimer(ITIMER_REAL, itvp, &oitv) < 0) {
+			fprintf(stderr, "setitimer: \n");
+			exit(-1);
+		}
+
+		cur_in = 0.0;
+		cur_out = 0.0;
+		while(*resetp == 0) {
+			if((packet = pcap_next(pcap, &header)) != NULL) {
+				ethernet = (struct ether_header *)packet;
+
+				if(header.len == 671429858) {
+					cur_in += 0.0;
+					cur_out += 0.0;
+				} else {
+					traf_io = calc_traf_io(ether_addrs, ethernet);
+					if(traf_io == 0) {
+						cur_in += header.len;
+					} else if(traf_io == 1) {
+						cur_out += header.len;
+					}
+					traf_io = 2;
+				}
+			}
+		}
+
+		cur_in /= 1024;
+		cur_out /= 1024;
+
+		if(show_in_bits == 1) {
+			cur_in *= 8;
+			cur_out *= 8;
+		}
+		
+		if(iteration >= ws_change || total_iteration == 0) {
+			printf("%11s\n%5s in %5s out\n", ifname, (show_in_bits == 1) ? bits_prefix : bytes_prefix, (show_in_bits == 1) ? bits_prefix : bytes_prefix);
+			if(iteration > 1) {
+				iteration = 1;
+			}
+		}
+
+		if(total_iteration > 0) {
+			printf("%8.2lf %9.2lf\n", cur_in, cur_out);
+		}
+
+		if(max_iteration > 0 && max_iteration == total_iteration) {
+			break;
+		}
+
+		iteration++;
+		total_iteration++;
+	}
+
+	pcap_close(pcap);
+
+	exit(0);
+}
+
+/* calculate if the packet is going in or out */
+unsigned int calc_traf_io(char *ether_addrs, struct ether_header *ethernet) {
+	/* 0 = in
+	 * 1 = out
+	 * 2 = error
+	 * GET IT!? GET IT?!?!??!!? :/ */
+	if(ethaddrsncmp(ether_addrs, ethernet->ether_shost, sizeof(ether_addrs)) == 0) {
+		return(1);
+	}
+	if(ethaddrsncmp(ether_addrs, ethernet->ether_dhost, sizeof(ether_addrs)) == 0) {
+		return(0);
+	}
+	return(2);
+}
+
+/* compare ethernet addresses */
+int ethaddrsncmp(const char *s1, const char *s2, size_t len) {
+	if(len == 0) {
+		return(0);
+	}
+
+	do {
+		if(*s1++ != *s2++) {
+			return(*(const unsigned char *)s1 - *(const unsigned char *)(s2 - 1));
+		}
+	} while(--len != 0);
+
+	return(0);
+}
+
+/* resets a global value */
+void reset_count(int signal) {
+	int *resetp = NULL;
+	resetp = &reset;
+
+	*resetp = 1;
+
+	return;
+}
+
+/* get windowsize */
+unsigned short get_windowsize(void) {
+	struct winsize ws;
+
+	if(ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) < 0) {
+		return(-1);
+	}
+
+	return(ws.ws_row);
+}
+
+void usage(const char *appname) {
+	printf("Usage: %s -i <interface> [-bhv] <filter>\n", appname);
+	printf("\t-i <interface>\t Specify interface to capture from\n"
+			"\t-b\t\t Show values in bits instead of bytes\n"
+			"\t-h\t\t Show this help text\n"
+			"\t-v\t\t Show version\n");
+
+	return;
+}