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/*
* MD5 interface for rsaref2.0
*
* These routines implement an interface for the RSA Laboratories
* implementation of the Message Digest 5 (MD5) algorithm. This
* algorithm is included in the rsaref2.0 package available from RSA in
* the US and foreign countries. Further information is available at
* www.rsa.com.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "ntp_fp.h"
#include "ntp_string.h"
#include "ntp_stdlib.h"
/* Disable the openssl md5 includes, because they'd clash with ours. */
/* #define NO_MD5 */
/* #define OPENSSL_NO_MD5 */
#undef OPENSSL
#include "ntp.h"
#include "global.h"
#include "ntp_md5.h"
/*
* MD5authencrypt - generate MD5 message authenticator
*
* Returns length of authenticator field.
*/
int
MD5authencrypt(
u_char *key, /* key pointer */
u_int32 *pkt, /* packet pointer */
int length /* packet length */
)
{
MD5_CTX md5;
u_char digest[16];
/*
* MD5 with key identifier concatenated with packet.
*/
MD5Init(&md5);
MD5Update(&md5, key, (u_int)cache_keylen);
MD5Update(&md5, (u_char *)pkt, (u_int)length);
MD5Final(digest, &md5);
memmove((u_char *)pkt + length + 4, digest, 16);
return (16 + 4);
}
/*
* MD5authdecrypt - verify MD5 message authenticator
*
* Returns one if authenticator valid, zero if invalid.
*/
int
MD5authdecrypt(
u_char *key, /* key pointer */
u_int32 *pkt, /* packet pointer */
int length, /* packet length */
int size /* MAC size */
)
{
MD5_CTX md5;
u_char digest[16];
/*
* MD5 with key identifier concatenated with packet.
*/
MD5Init(&md5);
MD5Update(&md5, key, (u_int)cache_keylen);
MD5Update(&md5, (u_char *)pkt, (u_int)length);
MD5Final(digest, &md5);
if (size != 16 + 4)
return (0);
return (!memcmp(digest, (char *)pkt + length + 4, 16));
}
/*
* Calculate the reference id from the address. If it is an IPv4
* address, use it as is. If it is an IPv6 address, do a md5 on
* it and use the bottom 4 bytes.
*/
u_int32
addr2refid(struct sockaddr_storage *addr)
{
MD5_CTX md5;
u_char digest[16];
u_int32 addr_refid;
if (addr->ss_family == AF_INET)
return (GET_INADDR(*addr));
MD5Init(&md5);
MD5Update(&md5, (u_char *)&GET_INADDR6(*addr),
sizeof(struct in6_addr));
MD5Final(digest, &md5);
memcpy(&addr_refid, digest, 4);
return (addr_refid);
}
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