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#include "socket.h"
#include "io.h"
#include "buffer.h"
#include "ip6.h"
#include "str.h"
#include "dns.h"
#include <errno.h>
#include <getopt.h>
#include "scan.h"
#include <stdlib.h>
struct state {
int64 a,b;
char buf[1024];
int connected;
int done,todo;
enum { UNDECIDED, FORA, FORB } dir;
};
int main(int argc,char* argv[]) {
int s=socket_tcp6();
uint32 scope_id;
char ip[16];
uint16 port;
char hisip[16];
uint16 hisport;
uint32 hisscope_id;
static char seed[128];
static stralloc fqdn;
static stralloc out;
if (argc!=4) {
usage:
buffer_putsflush(buffer_2,"usage: proxy myip myport hisip hisport\n"
"\n"
"e.g.: proxy 0 119 news.fu-berlin.de 119\n");
return 0;
}
if (argv[1][scan_ip6if(argv[1],ip,&scope_id)]) {
if (str_equal(argv[1],"0")) {
byte_zero(ip,16);
scope_id=0;
} else
goto usage;
}
if (argv[2][scan_ushort(argv[2],&port)]) goto usage;
if (argv[3][scan_ip6if(argv[3],hisip,&hisscope_id)]) {
dns_random_init(seed);
if (!stralloc_copys(&fqdn,argv[3])) goto nomem;
if (dns_ip4(&out,&fqdn) == -1) {
buffer_puts(buffer_2,"unable to find IP address for ");
buffer_puts(buffer_2,argv[3]);
buffer_puts(buffer_2,": ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
return 111;
}
} else
if (!stralloc_catb(&out,hisip,16)) {
nomem:
buffer_putsflush(buffer_2,"out of memory\n");
return 111;
}
if (argv[4][scan_ushort(argv[4],&hisport)]) goto usage;
if (socket_bind6_reuse(s,ip,port,scope_id)==-1) {
buffer_puts(buffer_2,"socket_bind6_reuse: ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
return 111;
}
if (socket_listen(s,16)==-1) {
buffer_puts(buffer_2,"socket_listen: ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
return 111;
}
if (!io_fd(s)) {
buffer_puts(buffer_2,"io_fd: ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
return 111;
}
io_wantread(s);
for (;;) {
int64 i;
io_wait();
while ((i=io_canread())!=-1) {
if (i==s) {
/* the read event is on the server socket */
/* that means it's an incoming connection */
int n;
while ((n=socket_accept6(s,ip,&port,&scope_id))!=-1) {
int x=socket_tcp6();
if (x==-1) {
buffer_puts(buffer_2,"socket_tcp6 failed: ");
fail:
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
io_close(n);
} else {
struct state* s=malloc(sizeof(struct state));
if (!s) goto closefail;
s->a=n; s->b=x; s->connected=0; s->done=s->todo=0;
s->dir=UNDECIDED;
io_nonblock(x);
socket_connect6(x,out.s,hisport,hisscope_id);
if (!io_fd(x) || !io_fd(n)) {
buffer_puts(buffer_2,"io_fd failed: ");
closefail:
free(s);
io_close(x);
goto fail;
}
io_setcookie(x,s);
io_setcookie(n,s);
io_wantwrite(x);
}
}
if (errno!=EAGAIN) {
buffer_puts(buffer_2,"socket_accept6 failed: ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
}
} else {
/* read event on an established connection */
struct state* s=io_getcookie(i);
int l=io_tryread(i,s->buf,sizeof(s->buf));
if (l==-1) {
buffer_puts(buffer_2,"io_tryread(");
buffer_putulong(buffer_2,i);
buffer_puts(buffer_2,"): ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
io_close(s->a);
io_close(s->b);
} else if (l==0) {
buffer_puts(buffer_2,"eof on fd #");
buffer_putulong(buffer_2,i);
buffer_putnlflush(buffer_2);
io_close(i);
} else {
int r;
switch (r=io_trywrite(i,s->buf,l)) {
case -1:
buffer_puts(buffer_2,"io_tryread(");
buffer_putulong(buffer_2,i);
buffer_puts(buffer_2,"): ");
buffer_puterror(buffer_2);
buffer_putnlflush(buffer_2);
io_close(i);
break;
case 0:
buffer_puts(buffer_2,"write eof on fd #");
buffer_putulong(buffer_2,i);
buffer_putnlflush(buffer_2);
io_close(i);
default:
if (r!=l) {
buffer_puts(buffer_2,"short write on fd #");
buffer_putulong(buffer_2,i);
buffer_puts(buffer_2,": wrote ");
buffer_putulong(buffer_2,r);
buffer_puts(buffer_2,", wanted to write ");
buffer_putulong(buffer_2,l);
buffer_putsflush(buffer_2,").\n");
}
}
}
}
}
}
return 0;
}
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