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/*
* DDNS v3 Client
*
* Author: Alan Yates <alany@ay.com.au>
* Version: $Id: auth.c,v 1.1.1.1 2002/07/19 11:47:20 alany Exp $
*/
#define _XOPEN_SOURCE
#ifdef WIN32
#include <windows.h>
#include <process.h>
#else
#include <unistd.h>
#endif
#include <string.h>
#include "ctx.h"
#include "auth.h"
#include "crypto.h"
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
static char *ddns3_auth_salts =
"abcdefghijklmnopqrstuzwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890./";
static int
auth_plaintext(struct ddns3_ctx *c, char *user, char *passwd) {
if(!strstr(c->hello, "plaintext")) return -1;
sprintf(c->buf, "LOGIN %s %s", user, passwd);
return 0;
}
#ifndef WIN32
static int
auth_crypt(struct ddns3_ctx *c, char *user, char *passwd) {
char salt[2];
char *hash;
if(!strstr(c->hello, "crypt")) return -1;
srand(getpid() * time(0));
salt[0] = ddns3_auth_salts[rand() % strlen(ddns3_auth_salts)];
salt[1] = ddns3_auth_salts[rand() % strlen(ddns3_auth_salts)];
hash = ddns3_crypto_crypt(passwd, salt);
sprintf(c->buf, "LOGIN %s %s", user, hash);
free(hash);
return 0;
}
#endif
static int
auth_md5(struct ddns3_ctx *c, char *user, char *passwd) {
char *hash;
if(!strstr(c->hello, "md5")) return -1;
hash = ddns3_crypto_md5hash(passwd, strlen(passwd));
sprintf(c->buf, "LOGIN %s %s", user, hash);
free(hash);
return 0;
}
static int
auth_ddns(struct ddns3_ctx *c, char *user, char *passwd) {
char *hash, *p;
char buf[4096];
if(!strstr(c->hello, "ddns")) return -1;
strcpy(buf, passwd);
strcat(buf, ":");
p = strstr(c->hello, "ddns{");
strncat(buf, p+5, 32);
hash = ddns3_crypto_md5hash(buf, strlen(buf));
sprintf(c->buf, "LOGIN %s %s", user, hash);
free(hash);
return 0;
}
/* FIXME: there is no server support for strong auth yet */
static int
auth_strong(struct ddns3_ctx *c, char *user, char *passwd) {
char *phash, *uhash, *challenge, *p;
char buf[4096];
int i;
if(!strstr(c->hello, "ddns")) return -1;
/* password hash */
strcpy(buf, passwd);
strcat(buf, ":");
p = strstr(c->hello, "ddns{");
strncat(buf, p+5, 32);
phash = ddns3_crypto_md5hash(buf, strlen(buf));
/* random challenge */
srand(getpid() * time(0));
for(i = 0; i < 100; i++) buf[i] = rand();
challenge = ddns3_crypto_md5hash(buf, 100);
/* username hash */
strcpy(buf, user);
strcat(buf, ":");
strncat(buf, challenge, 32);
uhash = ddns3_crypto_md5hash(buf, strlen(buf));
sprintf(c->buf, "LOGIN %s %s %s", uhash, phash, challenge);
free(uhash);
free(phash);
free(challenge);
return 0;
}
static struct ddns3_auth known_auths[] = {
{"plaintext", auth_plaintext},
#ifndef WIN32
{"crypt", auth_crypt},
#endif
{"md5", auth_md5},
{"ddns", auth_ddns},
{"strong", auth_strong},
{0, 0}
};
int
ddns3_auth_makechallenge(struct ddns3_ctx *c, char *auth, char *user, char *passwd) {
int i;
int ret = -2;
for(i = 0; known_auths[i].name; i++)
if(!strcmp(known_auths[i].name, auth)) {
ret = known_auths[i].makechallenge(c, user, passwd);
break;
}
if(ret < -1)
strcpy(c->buf, "client_error: authentication type unknown to client\n");
else if(ret < 0)
strcpy(c->buf, "client_error: authentication type not supported by server\n");
return ret;
}
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