/* * lib/crypto/keyhash_provider/hmac_md5.c * (I don't know) . * Copyright2001 by the Massachusetts Institute of Technology. * All Rights Reserved. * * Export of this software from the United States of America may * require a specific license from the United States Government. * It is the responsibility of any person or organization contemplating * export to obtain such a license before exporting. * * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and * distribute this software and its documentation for any purpose and * without fee is hereby granted, provided that the above copyright * notice appear in all copies and that both that copyright notice and * this permission notice appear in supporting documentation, and that * the name of M.I.T. not be used in advertising or publicity pertaining * to distribution of the software without specific, written prior * permission. Furthermore if you modify this software you must label * your software as modified software and not distribute it in such a * fashion that it might be confused with the original M.I.T. software. * M.I.T. makes no representations about the suitability of * this software for any purpose. It is provided "as is" without express * or implied warranty. * * * Implementation of the Microsoft hmac-md5 checksum type. * Implemented based on draft-brezak-win2k-krb-rc4-hmac-03 */ #include "k5-int.h" #include "keyhash_provider.h" #include "arcfour-int.h" #include "rsa-md5.h" #include "hash_provider.h" static krb5_error_code k5_hmac_md5_hash (const krb5_keyblock *key, krb5_keyusage usage, const krb5_data *iv, const krb5_data *input, krb5_data *output) { krb5_keyusage ms_usage; krb5_error_code ret; krb5_keyblock ks; krb5_data ds, ks_constant, md5tmp; krb5_MD5_CTX ctx; char t[4]; ds.length = key->length; ks.length = key->length; ds.data = malloc(ds.length); if (ds.data == NULL) return ENOMEM; ks.contents = (void *) ds.data; ks_constant.data = "signaturekey"; ks_constant.length = strlen(ks_constant.data)+1; /* Including null*/ ret = krb5_hmac( &krb5int_hash_md5, key, 1, &ks_constant, &ds); if (ret) goto cleanup; krb5_MD5Init (&ctx); ms_usage = krb5int_arcfour_translate_usage (usage); t[0] = (ms_usage) & 0xff; t[1] = (ms_usage>>8) & 0xff; t[2] = (ms_usage >>16) & 0xff; t[3] = (ms_usage>>24) & 0XFF; krb5_MD5Update (&ctx, (unsigned char * ) &t, 4); krb5_MD5Update (&ctx, (unsigned char *) input-> data, (unsigned int) input->length ); krb5_MD5Final(&ctx); md5tmp.data = (void *) ctx.digest; md5tmp.length = 16; ret = krb5_hmac ( &krb5int_hash_md5, &ks, 1, &md5tmp, output); cleanup: memset(&ctx, 0, sizeof(ctx)); memset (ks.contents, 0, ks.length); free (ks.contents); return ret; } const struct krb5_keyhash_provider krb5int_keyhash_hmac_md5 = { 16, k5_hmac_md5_hash, NULL /*checksum again*/ };