Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <time.h>
#ifdef WIN32
#include <winsock.h>
#include "winerr.h"
#define close closesocket
#define sleep Sleep
#define ONESEC 1000
#else
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <netdb.h>
#define ONESEC 1
#endif
#define VER "0.1"
#define PORT 7777
#define BUFFSZ 8192
void sampinfo(u_char *data, int size);
int put08(u_char *data, int num);
int get08(u_char *data, int *num);
int put16(u_char *data, int num);
int get16(u_char *data, int *num);
int put32(u_char *data, int num);
int get32(u_char *data, int *num);
int putsc(u_char *data, u_char *src);
int getsc(u_char *data, u_char **dst);
int putmm(u_char *data, u_char *src, int len);
int getmm(u_char *data, u_char *dst, int len);
void delimit(u_char *data);
int send_recv(int sd, u_char *in, int insz, u_char *out, int outsz, int err);
int timeout(int sock, int secs);
u_int resolv(char *host);
void std_err(void);
struct sockaddr_in peer;
int main(int argc, char *argv[]) {
struct sockaddr_in peerl;
int sd,
pl,
len;
u_short port = PORT;
u_char buff[BUFFSZ],
pass[64],
*p;
#ifdef WIN32
WSADATA wsadata;
WSAStartup(MAKEWORD(1,0), &wsadata);
#endif
setbuf(stdout, NULL);
fputs("\n"
"Hey this is the test "VER"\n"
"\n", stdout);
if(argc < 2) {
printf("\n"
"Usage: %s <host> [port(%hu)]\n"
"\n"
"\n", argv[0], port);
exit(1);
}
if(argc > 2) port = atoi(argv[2]);
peer.sin_addr.s_addr = resolv(argv[1]);
peer.sin_port = htons(port);
peer.sin_family = AF_INET;
peerl.sin_addr.s_addr = INADDR_ANY;
peerl.sin_port = htons(time(NULL));
peerl.sin_family = AF_INET;
printf("- target %s : %hu\n",
inet_ntoa(peer.sin_addr), ntohs(peer.sin_port));
sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if(sd < 0) std_err();
p = buff;
p += putmm(p, "SAMP", 4);
p += put32(p, peer.sin_addr.s_addr);
p += put16(p, ntohs(peer.sin_port));
p += put08(p, 'i');
len = send_recv(sd, buff, p - buff, buff, BUFFSZ, 1);
close(sd);
sampinfo(buff, len);
pass[0] = 0;
printf("- start thread:");
for(;;) {
pl = 1;
for(;;) {
printf("\n chat: ");
sd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if(sd < 0) std_err();
do {
peerl.sin_port++;
} while(bind(sd, (struct sockaddr *)&peerl, sizeof(peerl)) < 0);
p = buff;
p += put08(p, 3);
if(pass[0]) {
p += putsc(p, pass);
}
len = send_recv(sd, buff, p - buff, buff, BUFFSZ, 1);
close(sd);
if(buff[0] == 20) break;
if(buff[0] != 18) {
if((buff[0] == 19) || (buff[0] == 25)) {
// \wrong \not set
printf("\n- server is protected, insert the password:\n ");
fflush(stdin);
fgets(pass, sizeof(pass), stdin);
delimit(pass);
continue;
}
printf("\nError: unknown packet reply (%d)\n", buff[0]);
exit(1);
}
printf("%d ", pl);
pl++;
if(pl > 9999) pl = 0; // lame slow-networks work-around
}
printf("Full chat");
sleep(ONESEC);
}
return(0);
}
void sampinfo(u_char *data, int size) {
int info,
namelen,
modelen,
maplen,
pwd,
pl,
maxpl;
u_char *p,
*name,
*mode,
*map;
p = data;
p += 4 + 4 + 2;
p += get08(p, &info);
if(info != 'i') return;
p += get08(p, &pwd);
p += get16(p, &pl);
p += get16(p, &maxpl);
p += get32(p, &namelen);
name = p; p += namelen;
p += get32(p, &modelen);
mode = p; p += modelen;
p += get32(p, &maplen);
map = p; p += maplen;
printf(
"\n"
" name: %.*s\n"
" mode: %.*s\n"
" map: %.*s\n"
" chat: %hu/%hu\n"
" password: %s\n"
"\n",
namelen, name,
modelen, mode,
maplen, map,
pl, maxpl,
pwd ? "on" : "off");
}
int put08(u_char *data, int num) {
data[0] = num;
return(1);
}
int get08(u_char *data, int *num) {
if(num) {
*num = data[0];
}
return(1);
}
int put16(u_char *data, int num) {
data[0] = num;
data[1] = num >> 8;
return(2);
}
int get16(u_char *data, int *num) {
if(num) {
*num = data[0] | (data[1] << 8);
}
return(2);
}
int put32(u_char *data, int num) {
data[0] = num;
data[1] = num >> 8;
data[2] = num >> 16;
data[3] = num >> 24;
return(4);
}
int get32(u_char *data, int *num) {
if(num) {
*num = data[0] | (data[1] << 8) | (data[2] << 16) | (data[3] << 24);
}
return(4);
}
int putsc(u_char *data, u_char *src) {
return(sprintf(data, "%s", src) + 1);
}
int getsc(u_char *data, u_char **dst) {
*dst = data;
return(strlen(data) + 1);
}
int putmm(u_char *data, u_char *src, int len) {
memcpy(data, src, len);
return(len);
}
int getmm(u_char *data, u_char *dst, int len) {
memcpy(dst, data, len);
return(len);
}
void delimit(u_char *data) {
while(*data && (*data != '\n') && (*data != '\r')) data++;
*data = 0;
}
int send_recv(int sd, u_char *in, int insz, u_char *out, int outsz, int err) {
int retry,
len;
if(in && !out) {
if(sendto(sd, in, insz, 0, (struct sockaddr *)&peer, sizeof(peer))
< 0) std_err();
return(0);
} else if(in) {
for(retry = 3; retry; retry--) {
if(sendto(sd, in, insz, 0, (struct sockaddr *)&peer, sizeof(peer))
< 0) std_err();
if(!timeout(sd, 1)) break;
}
if(!retry) {
goto timeout_received;
}
} else {
if(timeout(sd, 3) < 0) {
goto timeout_received;
}
}
len = recvfrom(sd, out, outsz, 0, NULL, NULL);
if(len < 0) std_err();
return(len);
timeout_received:
if(err) {
printf("\nError: socket timeout, no reply received\n\n");
exit(1);
}
return(-1);
}
int timeout(int sock, int sec) {
struct timeval tout;
fd_set fd_read;
int err;
tout.tv_sec = sec;
tout.tv_usec = 0;
FD_ZERO(&fd_read);
FD_SET(sock, &fd_read);
err = select(sock + 1, &fd_read, NULL, NULL, &tout);
if(err < 0) std_err();
if(!err) return(-1);
return(0);
}
u_int resolv(char *host) {
struct hostent *hp;
u_int host_ip;
host_ip = inet_addr(host);
if(host_ip == INADDR_NONE) {
hp = gethostbyname(host);
if(!hp) {
printf("\nError: Unable to resolv hostname (%s)\n", host);
exit(1);
} else host_ip = *(u_int *)hp->h_addr;
}
return(host_ip);
}
#ifndef WIN32
void std_err(void) {
perror("\nError");
exit(1);
}
#endif