mirror of https://github.com/ARMmbed/mbed-os.git
127 lines
3.9 KiB
C
127 lines
3.9 KiB
C
/*
|
|
* chap-md5.c - New CHAP/MD5 implementation.
|
|
*
|
|
* Copyright (c) 2003 Paul Mackerras. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
*
|
|
* 2. The name(s) of the authors of this software must not be used to
|
|
* endorse or promote products derived from this software without
|
|
* prior written permission.
|
|
*
|
|
* 3. Redistributions of any form whatsoever must retain the following
|
|
* acknowledgment:
|
|
* "This product includes software developed by Paul Mackerras
|
|
* <paulus@samba.org>".
|
|
*
|
|
* THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
|
|
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
|
|
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
|
|
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
|
|
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
#include "ppp_opts.h"
|
|
#if PPP_SUPPORT && CHAP_SUPPORT /* don't build if not configured for use in lwipopts.h */
|
|
|
|
#if 0 /* UNUSED */
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#endif /* UNUSED */
|
|
|
|
#include "ppp_impl.h"
|
|
|
|
#include "chap-new.h"
|
|
#include "chap-md5.h"
|
|
#include "magic.h"
|
|
#include "pppcrypt.h"
|
|
|
|
#define MD5_HASH_SIZE 16
|
|
#define MD5_MIN_CHALLENGE 17
|
|
#define MD5_MAX_CHALLENGE 24
|
|
#define MD5_MIN_MAX_POWER_OF_TWO_CHALLENGE 3 /* 2^3-1 = 7, 17+7 = 24 */
|
|
|
|
#if PPP_SERVER
|
|
static void chap_md5_generate_challenge(ppp_pcb *pcb, unsigned char *cp) {
|
|
int clen;
|
|
LWIP_UNUSED_ARG(pcb);
|
|
|
|
clen = MD5_MIN_CHALLENGE + magic_pow(MD5_MIN_MAX_POWER_OF_TWO_CHALLENGE);
|
|
*cp++ = clen;
|
|
magic_random_bytes(cp, clen);
|
|
}
|
|
|
|
static int chap_md5_verify_response(ppp_pcb *pcb, int id, const char *name,
|
|
const unsigned char *secret, int secret_len,
|
|
const unsigned char *challenge, const unsigned char *response,
|
|
char *message, int message_space) {
|
|
lwip_md5_context ctx;
|
|
unsigned char idbyte = id;
|
|
unsigned char hash[MD5_HASH_SIZE];
|
|
int challenge_len, response_len;
|
|
LWIP_UNUSED_ARG(name);
|
|
LWIP_UNUSED_ARG(pcb);
|
|
|
|
challenge_len = *challenge++;
|
|
response_len = *response++;
|
|
if (response_len == MD5_HASH_SIZE) {
|
|
/* Generate hash of ID, secret, challenge */
|
|
lwip_md5_init(&ctx);
|
|
lwip_md5_starts(&ctx);
|
|
lwip_md5_update(&ctx, &idbyte, 1);
|
|
lwip_md5_update(&ctx, secret, secret_len);
|
|
lwip_md5_update(&ctx, challenge, challenge_len);
|
|
lwip_md5_finish(&ctx, hash);
|
|
lwip_md5_free(&ctx);
|
|
|
|
/* Test if our hash matches the peer's response */
|
|
if (memcmp(hash, response, MD5_HASH_SIZE) == 0) {
|
|
ppp_slprintf(message, message_space, "Access granted");
|
|
return 1;
|
|
}
|
|
}
|
|
ppp_slprintf(message, message_space, "Access denied");
|
|
return 0;
|
|
}
|
|
#endif /* PPP_SERVER */
|
|
|
|
static void chap_md5_make_response(ppp_pcb *pcb, unsigned char *response, int id, const char *our_name,
|
|
const unsigned char *challenge, const char *secret, int secret_len,
|
|
unsigned char *private_) {
|
|
lwip_md5_context ctx;
|
|
unsigned char idbyte = id;
|
|
int challenge_len = *challenge++;
|
|
LWIP_UNUSED_ARG(our_name);
|
|
LWIP_UNUSED_ARG(private_);
|
|
LWIP_UNUSED_ARG(pcb);
|
|
|
|
lwip_md5_init(&ctx);
|
|
lwip_md5_starts(&ctx);
|
|
lwip_md5_update(&ctx, &idbyte, 1);
|
|
lwip_md5_update(&ctx, (const u_char *)secret, secret_len);
|
|
lwip_md5_update(&ctx, challenge, challenge_len);
|
|
lwip_md5_finish(&ctx, &response[1]);
|
|
lwip_md5_free(&ctx);
|
|
response[0] = MD5_HASH_SIZE;
|
|
}
|
|
|
|
const struct chap_digest_type md5_digest = {
|
|
CHAP_MD5, /* code */
|
|
#if PPP_SERVER
|
|
chap_md5_generate_challenge,
|
|
chap_md5_verify_response,
|
|
#endif /* PPP_SERVER */
|
|
chap_md5_make_response,
|
|
NULL, /* check_success */
|
|
NULL, /* handle_failure */
|
|
};
|
|
|
|
#endif /* PPP_SUPPORT && CHAP_SUPPORT */
|