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/*
* This file is part of secnet.
* See LICENCE and this file CREDITS for full list of copyright holders.
* SPDX-License-Identifier: GPL-3.0-or-later
* There is NO WARRANTY.
*/
/*
test-example/bogus-setup-request 127.0.0.1 19098 test-example/inside/inside 127.0.0.1 16096 test-example/outside/outside
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
/*
| 00000 00 00 00 00 00 00 00 01 01 01 01 01 00 1a 74 65 ........ ......te |
~~~~~~~~~~~ ~~~~~~~~~~~ ~~~~~~~~~~~ ~~~~~|~~~~~
sessionid sender's type sender's
zero in index fixed for name
msg1 msg1
| 00010 73 74 2d 65 78 61 6d 70 6c 65 2f 69 6e 73 69 64 st-examp le/insid |
| 00020 65 2f 69 6e 73 69 64 65 00 1c 74 65 73 74 2d 65 e/inside ..test-e |
~~~~~|~~~~~~~~~~~~~~~~~
recipient's name
| 00030 78 61 6d 70 6c 65 2f 6f 75 74 73 69 64 65 2f 6f xample/o utside/o |
| 00040 75 74 73 69 64 65 8d f0 3f 35 d6 c8 1f c0 utside.. ?5.... |
~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~
sender's nonce
*/
typedef struct {
const char *name;
union {
struct sockaddr sa;
struct sockaddr_in sin;
};
} Ep;
static void endaddr(Ep *ep, char **argv, int base) {
int r;
ep->sin.sin_family=AF_INET;
r=inet_aton(argv[base],&ep->sin.sin_addr); assert(r);
ep->sin.sin_port=htons(atoi(argv[base+1]));
ep->name=argv[base+2];
}
static void endname(uint8_t **msgp, const Ep *ep) {
int l=strlen(ep->name); assert(l<=65535);
*(*msgp)++ = l>>8;
*(*msgp)++ = l;
memcpy(*msgp, ep->name, l);
*msgp += l;
}
static Ep us, them;
int main(int argc, char **argv) {
int r;
assert(argc==7);
endaddr(&us,argv,1);
endaddr(&them,argv,4);
static const uint8_t mprefix[]={
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01,
0x01, 0x01, 0x01, 0x01,
};
static const uint8_t msuffix[]={
/* our nonce, fixed he he */
0x8d, 0xf0, 0x3f, 0x35, 0xd6, 0xc8, 0x1f, 0xc0
};
int msglen= (sizeof(mprefix) +
2+strlen(us.name) +
2+strlen(them.name) +
sizeof(msuffix));
uint8_t msg[msglen];
uint8_t *msgp=msg;
#define PREFIXSUFFIX(prefixsuffix) do { \
memcpy(msgp,prefixsuffix,sizeof(prefixsuffix)); \
msgp += sizeof(prefixsuffix); \
}while(0)
PREFIXSUFFIX(mprefix);
endname(&msgp,&us);
endname(&msgp,&them);
PREFIXSUFFIX(msuffix);
assert(msgp == msg+msglen);
struct protoent *proto=getprotobyname("udp");
int fd=socket(AF_INET, SOCK_DGRAM, proto->p_proto);
r=bind(fd,&us.sa,sizeof(us.sin)); if (r) { perror("bind us2"); exit(1); }
for (;;) {
r=sendto(fd,msg,msglen,0,&them.sa,sizeof(them.sin));
if (r < 0) perror("sendto");
r=getchar();
if (r==EOF) {
if (ferror(stdin)) { perror("getchar"); exit(1); }
break;
}
if (r!='\n')
break;
}
exit(0);
}
|
