haproxy/admin/dyncookie/dyncookie.c
Willy Tarreau 6807c7f6e1 ADMIN: dyncookie: implement a simple dynamic cookie calculator
This utility can be useful to figure what cookie value a server will
have based on the secret, its IP and its port.
2021-08-11 14:07:45 +02:00

56 lines
1.3 KiB
C

/*
* Dynamic server cookie calculator
*
* Copyright 2021 Willy Tarreau <w@1wt.eu>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <arpa/inet.h>
#include <import/xxhash.h>
__attribute__((noreturn)) void die(int code, const char *format, ...)
{
va_list args;
va_start(args, format);
vfprintf(stderr, format, args);
va_end(args);
exit(code);
}
int main(int argc, char **argv)
{
size_t key_len;
int addr_len;
char *buf;
int port;
if (argc < 4)
die(1, "Usage: %s <key> <ip> <port>\n", argv[0]);
key_len = strlen(argv[1]);
buf = realloc(strdup(argv[1]), key_len + 16 + 4);
if (!buf)
die(2, "Not enough memory\n");
if (inet_pton(AF_INET, argv[2], buf + key_len) > 0)
addr_len = 4;
else if (inet_pton(AF_INET6, argv[2], buf + key_len) > 0)
addr_len = 16;
else
die(3, "Cannot parse address <%s> as IPv4/IPv6\n", argv[2]);
port = htonl(atoi(argv[3]));
memcpy(buf + key_len + addr_len, &port, 4);
printf("%016llx\n", (long long)XXH64(buf, key_len + addr_len + 4, 0));
return 0;
}