Beispiel #1
0
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_authenticator_checksum(krb5_context context,
				   krb5_auth_context ac,
				   void *data,
				   size_t len)
{
    krb5_error_code ret;
    krb5_keyblock *key;
    krb5_authenticator authenticator;
    krb5_crypto crypto;

    ret = krb5_auth_con_getauthenticator (context,
				      ac,
				      &authenticator);
    if(ret)
	return ret;
    if(authenticator->cksum == NULL) {
	krb5_free_authenticator(context, &authenticator);
	return -17;
    }
    ret = krb5_auth_con_getkey(context, ac, &key);
    if(ret) {
	krb5_free_authenticator(context, &authenticator);
	return ret;
    }
    ret = krb5_crypto_init(context, key, 0, &crypto);
    if(ret)
	goto out;
    ret = krb5_verify_checksum (context,
				crypto,
				KRB5_KU_AP_REQ_AUTH_CKSUM,
				data,
				len,
				authenticator->cksum);
    krb5_crypto_destroy(context, crypto);
out:
    krb5_free_authenticator(context, &authenticator);
    krb5_free_keyblock(context, key);
    return ret;
}
Beispiel #2
0
static krb5_error_code
storage_to_etext(krb5_context context,
		 krb5_storage *sp,
		 const krb5_keyblock *key, 
		 krb5_data *enc_data)
{
    krb5_error_code ret;
    krb5_crypto crypto;
    krb5_ssize_t size;
    krb5_data data;

    /* multiple of eight bytes */

    size = krb5_storage_seek(sp, 0, SEEK_END);
    if (size < 0)
	return EINVAL;
    size = 8 - (size & 7);

    ret = krb5_storage_write(sp, eightzeros, size);
    if (ret != size)
	return EINVAL;

    ret = krb5_storage_to_data(sp, &data);
    if (ret)
	return ret;

    ret = krb5_crypto_init(context, key, ETYPE_DES_PCBC_NONE, &crypto);
    if (ret) {
	krb5_data_free(&data);
	return ret;
    }

    ret = krb5_encrypt(context, crypto, 0, data.data, data.length, enc_data);

    krb5_data_free(&data);
    krb5_crypto_destroy(context, crypto);

    return ret;
}
Beispiel #3
0
static void
print_and_decode_tkt (krb5_context context,
		      krb5_data *ticket,
		      krb5_principal server,
		      krb5_enctype enctype)
{
    krb5_error_code ret;
    krb5_crypto crypto;
    krb5_data dec_data;
    size_t len;
    EncTicketPart decr_part;
    krb5_keyblock key;
    Ticket tkt;

    ret = decode_Ticket (ticket->data, ticket->length, &tkt, &len);
    if (ret)
	krb5_err (context, 1, ret, "decode_Ticket");

    ret = krb5_string_to_key (context, enctype, "foo", server, &key);
    if (ret)
	krb5_err (context, 1, ret, "krb5_string_to_key");

    ret = krb5_crypto_init(context, &key, 0, &crypto);
    if (ret)
	krb5_err (context, 1, ret, "krb5_crypto_init");

    ret = krb5_decrypt_EncryptedData (context, crypto, KRB5_KU_TICKET,
				      &tkt.enc_part, &dec_data);
    krb5_crypto_destroy (context, crypto);
    if (ret)
	krb5_err (context, 1, ret, "krb5_decrypt_EncryptedData");
    ret = decode_EncTicketPart (dec_data.data, dec_data.length,
				&decr_part, &len);
    krb5_data_free (&dec_data);
    if (ret)
	krb5_err (context, 1, ret, "krb5_decode_EncTicketPart");
    free_EncTicketPart(&decr_part);
}
Beispiel #4
0
int
main(int argc, char **argv)
{
    krb5_keyblock keyblock;
    krb5_error_code ret;
    krb5_context context;
    krb5_crypto crypto;
    int i;

    ret = krb5_init_context(&context);
    if (ret)
	errx(1, "krb5_context_init: %d", ret);

    ret = krb5_generate_random_keyblock(context,
					ENCTYPE_AES256_CTS_HMAC_SHA1_96,
					&keyblock);
    if (ret)
	krb5_err(context, 1, ret, "krb5_generate_random_keyblock");

    ret = krb5_crypto_init(context, &keyblock, 0, &crypto);
    if (ret)
	krb5_err(context, 1, ret, "krb5_crypto_init");

    test_special(context, crypto, 1, 60);
    test_special(context, crypto, 0, 60);

    for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
	test_range(&tests[i], 1, context, crypto);
	test_range(&tests[i], 0, context, crypto);
    }

    krb5_free_keyblock_contents(context, &keyblock);
    krb5_crypto_destroy(context, crypto);
    krb5_free_context(context);

    return 0;
}
Beispiel #5
0
static krb5_error_code
decrypt_authenticator (krb5_context context,
		       EncryptionKey *key,
		       EncryptedData *enc_part,
		       Authenticator *authenticator,
		       krb5_key_usage usage)
{
    krb5_error_code ret;
    krb5_data plain;
    size_t len;
    krb5_crypto crypto;

    ret = krb5_crypto_init(context, key, 0, &crypto);
    if (ret)
	return ret;
    ret = krb5_decrypt_EncryptedData (context,
				      crypto,
				      usage /* KRB5_KU_AP_REQ_AUTH */,
				      enc_part,
				      &plain);
    /* for backwards compatibility, also try the old usage */
    if (ret && usage == KRB5_KU_TGS_REQ_AUTH)
	ret = krb5_decrypt_EncryptedData (context,
					  crypto,
					  KRB5_KU_AP_REQ_AUTH,
					  enc_part,
					  &plain);
    krb5_crypto_destroy(context, crypto);
    if (ret)
	return ret;

    ret = decode_Authenticator(plain.data, plain.length,
			       authenticator, &len);
    krb5_data_free (&plain);
    return ret;
}
Beispiel #6
0
static krb5_error_code
tgs_parse_request(krb5_context context, 
		  krb5_kdc_configuration *config,
		  KDC_REQ_BODY *b,
		  const PA_DATA *tgs_req,
		  hdb_entry_ex **krbtgt,
		  krb5_enctype *krbtgt_etype,
		  krb5_ticket **ticket,
		  const char **e_text,
		  const char *from,
		  const struct sockaddr *from_addr,
		  time_t **csec,
		  int **cusec,
		  AuthorizationData **auth_data)
{
    krb5_ap_req ap_req;
    krb5_error_code ret;
    krb5_principal princ;
    krb5_auth_context ac = NULL;
    krb5_flags ap_req_options;
    krb5_flags verify_ap_req_flags;
    krb5_crypto crypto;
    Key *tkey;

    *auth_data = NULL;
    *csec  = NULL;
    *cusec = NULL;

    memset(&ap_req, 0, sizeof(ap_req));
    ret = krb5_decode_ap_req(context, &tgs_req->padata_value, &ap_req);
    if(ret){
	kdc_log(context, config, 0, "Failed to decode AP-REQ: %s", 
		krb5_get_err_text(context, ret));
	goto out;
    }

    if(!get_krbtgt_realm(&ap_req.ticket.sname)){
	/* XXX check for ticket.sname == req.sname */
	kdc_log(context, config, 0, "PA-DATA is not a ticket-granting ticket");
	ret = KRB5KDC_ERR_POLICY; /* ? */
	goto out;
    }
    
    _krb5_principalname2krb5_principal(context,
				       &princ,
				       ap_req.ticket.sname,
				       ap_req.ticket.realm);
    
    ret = _kdc_db_fetch(context, config, princ, HDB_F_GET_KRBTGT, NULL, krbtgt);

    if(ret) {
	char *p;
	ret = krb5_unparse_name(context, princ, &p);
	if (ret != 0)
	    p = "<unparse_name failed>";
	krb5_free_principal(context, princ);
	kdc_log(context, config, 0,
		"Ticket-granting ticket not found in database: %s: %s",
		p, krb5_get_err_text(context, ret));
	if (ret == 0)
	    free(p);
	ret = KRB5KRB_AP_ERR_NOT_US;
	goto out;
    }
    
    if(ap_req.ticket.enc_part.kvno && 
       *ap_req.ticket.enc_part.kvno != (*krbtgt)->entry.kvno){
	char *p;

	ret = krb5_unparse_name (context, princ, &p);
	krb5_free_principal(context, princ);
	if (ret != 0)
	    p = "<unparse_name failed>";
	kdc_log(context, config, 0,
		"Ticket kvno = %d, DB kvno = %d (%s)", 
		*ap_req.ticket.enc_part.kvno,
		(*krbtgt)->entry.kvno,
		p);
	if (ret == 0)
	    free (p);
	ret = KRB5KRB_AP_ERR_BADKEYVER;
	goto out;
    }

    *krbtgt_etype = ap_req.ticket.enc_part.etype;

    ret = hdb_enctype2key(context, &(*krbtgt)->entry, 
			  ap_req.ticket.enc_part.etype, &tkey);
    if(ret){
	char *str, *p;
	krb5_enctype_to_string(context, ap_req.ticket.enc_part.etype, &str);
	krb5_unparse_name(context, princ, &p);
	kdc_log(context, config, 0,
		"No server key with enctype %s found for %s", str, p);
	free(str);
	free(p);
	ret = KRB5KRB_AP_ERR_BADKEYVER;
	goto out;
    }
    
    if (b->kdc_options.validate)
	verify_ap_req_flags = KRB5_VERIFY_AP_REQ_IGNORE_INVALID;
    else
	verify_ap_req_flags = 0;

    ret = krb5_verify_ap_req2(context,
			      &ac,
			      &ap_req,
			      princ,
			      &tkey->key,
			      verify_ap_req_flags,
			      &ap_req_options,
			      ticket,
			      KRB5_KU_TGS_REQ_AUTH);
			     
    krb5_free_principal(context, princ);
    if(ret) {
	kdc_log(context, config, 0, "Failed to verify AP-REQ: %s", 
		krb5_get_err_text(context, ret));
	goto out;
    }

    {
	krb5_authenticator auth;

	ret = krb5_auth_con_getauthenticator(context, ac, &auth);
	if (ret == 0) {
	    *csec   = malloc(sizeof(**csec));
	    if (*csec == NULL) {
		krb5_free_authenticator(context, &auth);
		kdc_log(context, config, 0, "malloc failed");
		goto out;
	    }
	    **csec  = auth->ctime;
	    *cusec  = malloc(sizeof(**cusec));
	    if (*cusec == NULL) {
		krb5_free_authenticator(context, &auth);
		kdc_log(context, config, 0, "malloc failed");
		goto out;
	    }
	    **cusec  = auth->cusec;
	    krb5_free_authenticator(context, &auth);
	}
    }

    ret = tgs_check_authenticator(context, config, 
				  ac, b, e_text, &(*ticket)->ticket.key);
    if (ret) {
	krb5_auth_con_free(context, ac);
	goto out;
    }

    if (b->enc_authorization_data) {
	krb5_keyblock *subkey;
	krb5_data ad;
	ret = krb5_auth_con_getremotesubkey(context,
					    ac,
					    &subkey);
	if(ret){
	    krb5_auth_con_free(context, ac);
	    kdc_log(context, config, 0, "Failed to get remote subkey: %s", 
		    krb5_get_err_text(context, ret));
	    goto out;
	}
	if(subkey == NULL){
	    ret = krb5_auth_con_getkey(context, ac, &subkey);
	    if(ret) {
		krb5_auth_con_free(context, ac);
		kdc_log(context, config, 0, "Failed to get session key: %s", 
			krb5_get_err_text(context, ret));
		goto out;
	    }
	}
	if(subkey == NULL){
	    krb5_auth_con_free(context, ac);
	    kdc_log(context, config, 0,
		    "Failed to get key for enc-authorization-data");
	    ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
	    goto out;
	}
	ret = krb5_crypto_init(context, subkey, 0, &crypto);
	if (ret) {
	    krb5_auth_con_free(context, ac);
	    kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
		    krb5_get_err_text(context, ret));
	    goto out;
	}
	ret = krb5_decrypt_EncryptedData (context,
					  crypto,
					  KRB5_KU_TGS_REQ_AUTH_DAT_SUBKEY,
					  b->enc_authorization_data,
					  &ad);
	krb5_crypto_destroy(context, crypto);
	if(ret){
	    krb5_auth_con_free(context, ac);
	    kdc_log(context, config, 0, 
		    "Failed to decrypt enc-authorization-data");
	    ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
	    goto out;
	}
	krb5_free_keyblock(context, subkey);
	ALLOC(*auth_data);
	if (*auth_data == NULL) {
	    krb5_auth_con_free(context, ac);
	    ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
	    goto out;
	}
	ret = decode_AuthorizationData(ad.data, ad.length, *auth_data, NULL);
	if(ret){
	    krb5_auth_con_free(context, ac);
	    free(*auth_data);
	    *auth_data = NULL;
	    kdc_log(context, config, 0, "Failed to decode authorization data");
	    ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
	    goto out;
	}
    }

    krb5_auth_con_free(context, ac);
    
out:
    free_AP_REQ(&ap_req);
    
    return ret;
}
Beispiel #7
0
static int
iov_test(krb5_context context)
{
    krb5_enctype enctype = KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96;
    krb5_error_code ret;
    krb5_crypto crypto;
    krb5_keyblock key;
    krb5_data signonly, in, in2;
    krb5_crypto_iov iov[6];
    size_t len, i;
    unsigned char *base, *p;

    ret = krb5_generate_random_keyblock(context, enctype, &key);
    if (ret)
	krb5_err(context, 1, ret, "krb5_generate_random_keyblock");

    ret = krb5_crypto_init(context, &key, 0, &crypto);
    if (ret)
	krb5_err(context, 1, ret, "krb5_crypto_init");


    ret = krb5_crypto_length(context, crypto, KRB5_CRYPTO_TYPE_HEADER, &len);
    if (ret)
	krb5_err(context, 1, ret, "krb5_crypto_length");

    signonly.data = "This should be signed";
    signonly.length = strlen(signonly.data);
    in.data = "inputdata";
    in.length = strlen(in.data);

    in2.data = "INPUTDATA";
    in2.length = strlen(in2.data);


    memset(iov, 0, sizeof(iov));

    iov[0].flags = KRB5_CRYPTO_TYPE_HEADER;
    iov[1].flags = KRB5_CRYPTO_TYPE_DATA;
    iov[1].data = in;
    iov[2].flags = KRB5_CRYPTO_TYPE_SIGN_ONLY;
    iov[2].data = signonly;
    iov[3].flags = KRB5_CRYPTO_TYPE_EMPTY;
    iov[4].flags = KRB5_CRYPTO_TYPE_PADDING;
    iov[5].flags = KRB5_CRYPTO_TYPE_TRAILER;

    ret = krb5_crypto_length_iov(context, crypto, iov,
				 sizeof(iov)/sizeof(iov[0]));
    if (ret)
	krb5_err(context, 1, ret, "krb5_crypto_length_iov");

    for (len = 0, i = 0; i < sizeof(iov)/sizeof(iov[0]); i++) {
	if (iov[i].flags == KRB5_CRYPTO_TYPE_SIGN_ONLY)
	    continue;
	len += iov[i].data.length;
    }

    base = emalloc(len);

    /*
     * Allocate data for the fields
     */

    for (p = base, i = 0; i < sizeof(iov)/sizeof(iov[0]); i++) {
	if (iov[i].flags == KRB5_CRYPTO_TYPE_SIGN_ONLY)
	    continue;;
	iov[i].data.data = p;
	p += iov[i].data.length;
    }
    assert(iov[1].data.length == in.length);
    memcpy(iov[1].data.data, in.data, iov[1].data.length);

    /*
     * Encrypt
     */

    ret = krb5_encrypt_iov_ivec(context, crypto, 7, iov,
				sizeof(iov)/sizeof(iov[0]), NULL);
    if (ret)
	krb5_err(context, 1, ret, "krb5_encrypt_iov_ivec");

    /*
     * Decrypt
     */

    ret = krb5_decrypt_iov_ivec(context, crypto, 7,
				iov, sizeof(iov)/sizeof(iov[0]), NULL);
    if (ret)
	krb5_err(context, 1, ret, "krb5_decrypt_iov_ivec");

    /*
     * Verify data
     */

    if (krb5_data_cmp(&iov[1].data, &in) != 0)
	krb5_errx(context, 1, "decrypted data not same");

    /*
     * Free memory
     */

    free(base);

    /* Set up for second try */

    iov[3].flags = KRB5_CRYPTO_TYPE_DATA;
    iov[3].data = in;

    ret = krb5_crypto_length_iov(context, crypto,
				 iov, sizeof(iov)/sizeof(iov[0]));
    if (ret)
	krb5_err(context, 1, ret, "krb5_crypto_length_iov");

    for (len = 0, i = 0; i < sizeof(iov)/sizeof(iov[0]); i++) {
	if (iov[i].flags == KRB5_CRYPTO_TYPE_SIGN_ONLY)
	    continue;
	len += iov[i].data.length;
    }

    base = emalloc(len);

    /*
     * Allocate data for the fields
     */

    for (p = base, i = 0; i < sizeof(iov)/sizeof(iov[0]); i++) {
	if (iov[i].flags == KRB5_CRYPTO_TYPE_SIGN_ONLY)
	    continue;;
	iov[i].data.data = p;
	p += iov[i].data.length;
    }
    assert(iov[1].data.length == in.length);
    memcpy(iov[1].data.data, in.data, iov[1].data.length);

    assert(iov[3].data.length == in2.length);
    memcpy(iov[3].data.data, in2.data, iov[3].data.length);



    /*
     * Encrypt
     */

    ret = krb5_encrypt_iov_ivec(context, crypto, 7,
				iov, sizeof(iov)/sizeof(iov[0]), NULL);
    if (ret)
	krb5_err(context, 1, ret, "krb5_encrypt_iov_ivec");

    /*
     * Decrypt
     */

    ret = krb5_decrypt_iov_ivec(context, crypto, 7,
				iov, sizeof(iov)/sizeof(iov[0]), NULL);
    if (ret)
	krb5_err(context, 1, ret, "krb5_decrypt_iov_ivec");

    /*
     * Verify data
     */

    if (krb5_data_cmp(&iov[1].data, &in) != 0)
	krb5_errx(context, 1, "decrypted data 2.1 not same");

    if (krb5_data_cmp(&iov[3].data, &in2) != 0)
	krb5_errx(context, 1, "decrypted data 2.2 not same");

    /*
     * Free memory
     */

    free(base);

    krb5_crypto_destroy(context, crypto);

    krb5_free_keyblock_contents(context, &key);

    return 0;
}
/* DCE compatible decrypt proc */
krb5_error_code KRB5_CALLCONV
_krb5_decrypt_tkt_with_subkey (krb5_context context,
			       krb5_keyblock *key,
			       krb5_key_usage usage,
			       krb5_const_pointer skey,
			       krb5_kdc_rep *dec_rep)
{
    const krb5_keyblock *subkey = skey;
    krb5_error_code ret = 0;
    krb5_data data;
    size_t size;
    krb5_crypto crypto;

    assert(usage == 0);

    krb5_data_zero(&data);

    /*
     * start out with trying with subkey if we have one
     */
    if (subkey) {
	ret = krb5_crypto_init(context, subkey, 0, &crypto);
	if (ret)
	    return ret;
	ret = krb5_decrypt_EncryptedData (context,
					  crypto,
					  KRB5_KU_TGS_REP_ENC_PART_SUB_KEY,
					  &dec_rep->kdc_rep.enc_part,
					  &data);
	/*
	 * If the is Windows 2000 DC, we need to retry with key usage
	 * 8 when doing ARCFOUR.
	 */
	if (ret && subkey->keytype == ETYPE_ARCFOUR_HMAC_MD5) {
	    ret = krb5_decrypt_EncryptedData(context,
					     crypto,
					     8,
					     &dec_rep->kdc_rep.enc_part,
					     &data);
	}
	krb5_crypto_destroy(context, crypto);
    }
    if (subkey == NULL || ret) {
	ret = krb5_crypto_init(context, key, 0, &crypto);
	if (ret)
	    return ret;
	ret = krb5_decrypt_EncryptedData (context,
					  crypto,
					  KRB5_KU_TGS_REP_ENC_PART_SESSION,
					  &dec_rep->kdc_rep.enc_part,
					  &data);
	krb5_crypto_destroy(context, crypto);
    }
    if (ret)
	return ret;

    ret = decode_EncASRepPart(data.data,
			      data.length,
			      &dec_rep->enc_part,
			      &size);
    if (ret)
	ret = decode_EncTGSRepPart(data.data,
				   data.length,
				   &dec_rep->enc_part,
				   &size);
    if (ret)
      krb5_set_error_message(context, ret,
			     N_("Failed to decode encpart in ticket", ""));
    krb5_data_free (&data);
    return ret;
}
krb5_error_code
_krb5_init_tgs_req(krb5_context context,
		   krb5_ccache ccache,
		   krb5_addresses *addresses,
		   krb5_kdc_flags flags,
		   krb5_const_principal impersonate_principal,
		   Ticket *second_ticket,
		   krb5_creds *in_creds,
		   krb5_creds *krbtgt,
		   unsigned nonce,
		   METHOD_DATA *padata,
		   krb5_keyblock **subkey,
		   TGS_REQ *t)
{
    krb5_auth_context ac = NULL;
    krb5_error_code ret = 0;
    
    /* inherit the forwardable/proxyable flags from the krbtgt */
    flags.b.forwardable = krbtgt->flags.b.forwardable;
    flags.b.proxiable = krbtgt->flags.b.proxiable;

    if (ccache->ops->tgt_req) {
	KERB_TGS_REQ_OUT out;
	KERB_TGS_REQ_IN in;
	
	memset(&in, 0, sizeof(in));
	memset(&out, 0, sizeof(out));

	ret = ccache->ops->tgt_req(context, ccache, &in, &out);
	if (ret)
	    return ret;

	free_KERB_TGS_REQ_OUT(&out);
	return 0;
    }


    memset(t, 0, sizeof(*t));

    if (impersonate_principal) {
	krb5_crypto crypto;
	PA_S4U2Self self;
	krb5_data data;
	void *buf;
	size_t size, len;

	self.name = impersonate_principal->name;
	self.realm = impersonate_principal->realm;
	self.auth = rk_UNCONST("Kerberos");
	
	ret = _krb5_s4u2self_to_checksumdata(context, &self, &data);
	if (ret)
	    goto fail;

	ret = krb5_crypto_init(context, &krbtgt->session, 0, &crypto);
	if (ret) {
	    krb5_data_free(&data);
	    goto fail;
	}

	ret = krb5_create_checksum(context,
				   crypto,
				   KRB5_KU_OTHER_CKSUM,
				   0,
				   data.data,
				   data.length,
				   &self.cksum);
	krb5_crypto_destroy(context, crypto);
	krb5_data_free(&data);
	if (ret)
	    goto fail;

	ASN1_MALLOC_ENCODE(PA_S4U2Self, buf, len, &self, &size, ret);
	free_Checksum(&self.cksum);
	if (ret)
	    goto fail;
	if (len != size)
	    krb5_abortx(context, "internal asn1 error");
	
	ret = krb5_padata_add(context, padata, KRB5_PADATA_FOR_USER, buf, len);
	if (ret)
	    goto fail;
    }

    t->pvno = 5;
    t->msg_type = krb_tgs_req;
    if (in_creds->session.keytype) {
	ALLOC_SEQ(&t->req_body.etype, 1);
	if(t->req_body.etype.val == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_message(context, ret,
				   N_("malloc: out of memory", ""));
	    goto fail;
	}
	t->req_body.etype.val[0] = in_creds->session.keytype;
    } else {
	ret = _krb5_init_etype(context,
			       KRB5_PDU_TGS_REQUEST,
			       &t->req_body.etype.len,
			       &t->req_body.etype.val,
			       NULL);
    }
    if (ret)
	goto fail;
    t->req_body.addresses = addresses;
    t->req_body.kdc_options = flags.b;
    ret = copy_Realm(&in_creds->server->realm, &t->req_body.realm);
    if (ret)
	goto fail;
    ALLOC(t->req_body.sname, 1);
    if (t->req_body.sname == NULL) {
	ret = ENOMEM;
	krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
	goto fail;
    }

    /* some versions of some code might require that the client be
       present in TGS-REQs, but this is clearly against the spec */

    ret = copy_PrincipalName(&in_creds->server->name, t->req_body.sname);
    if (ret)
	goto fail;

    /* req_body.till should be NULL if there is no endtime specified,
       but old MIT code (like DCE secd) doesn't like that */
    ALLOC(t->req_body.till, 1);
    if(t->req_body.till == NULL){
	ret = ENOMEM;
	krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
	goto fail;
    }
    *t->req_body.till = in_creds->times.endtime;

    t->req_body.nonce = nonce;
    if(second_ticket){
	ALLOC(t->req_body.additional_tickets, 1);
	if (t->req_body.additional_tickets == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_message(context, ret,
				   N_("malloc: out of memory", ""));
	    goto fail;
	}
	ALLOC_SEQ(t->req_body.additional_tickets, 1);
	if (t->req_body.additional_tickets->val == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_message(context, ret,
				   N_("malloc: out of memory", ""));
	    goto fail;
	}
	ret = copy_Ticket(second_ticket, t->req_body.additional_tickets->val);
	if (ret)
	    goto fail;
    }
    ALLOC(t->padata, 1);
    if (t->padata == NULL) {
	ret = ENOMEM;
	krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
	goto fail;
    }
    ALLOC_SEQ(t->padata, 1 + padata->len);
    if (t->padata->val == NULL) {
	ret = ENOMEM;
	krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
	goto fail;
    }
    {
	size_t i;
	for (i = 0; i < padata->len; i++) {
	    ret = copy_PA_DATA(&padata->val[i], &t->padata->val[i + 1]);
	    if (ret) {
		krb5_set_error_message(context, ret,
				       N_("malloc: out of memory", ""));
		goto fail;
	    }
	}
    }

    ret = krb5_auth_con_init(context, &ac);
    if(ret)
	goto fail;

    ret = krb5_auth_con_generatelocalsubkey(context, ac, &krbtgt->session);
    if (ret)
	goto fail;

    ret = set_auth_data (context, &t->req_body, &in_creds->authdata,
			 ac->local_subkey);
    if (ret)
	goto fail;

    ret = make_pa_tgs_req(context,
			  ac,
			  &t->req_body,
			  &t->padata->val[0],
			  ccache,
			  krbtgt);
    if(ret)
	goto fail;

    ret = krb5_auth_con_getlocalsubkey(context, ac, subkey);
    if (ret)
	goto fail;

fail:
    if (ac)
	krb5_auth_con_free(context, ac);
    if (ret) {
	t->req_body.addresses = NULL;
	free_TGS_REQ (t);
    }
    return ret;
}
Beispiel #10
0
krb5_error_code
_krb5_mk_req_internal(krb5_context context,
		      krb5_auth_context *auth_context,
		      const krb5_flags ap_req_options,
		      krb5_data *in_data,
		      krb5_creds *in_creds,
		      krb5_data *outbuf,
		      krb5_key_usage checksum_usage,
		      krb5_key_usage encrypt_usage)
{
    krb5_error_code ret;
    krb5_data authenticator;
    Checksum c;
    Checksum *c_opt;
    krb5_auth_context ac;

    if(auth_context) {
	if(*auth_context == NULL)
	    ret = krb5_auth_con_init(context, auth_context);
	else
	    ret = 0;
	ac = *auth_context;
    } else
	ret = krb5_auth_con_init(context, &ac);
    if(ret)
	return ret;

    if(ac->local_subkey == NULL && (ap_req_options & AP_OPTS_USE_SUBKEY)) {
	ret = krb5_auth_con_generatelocalsubkey(context,
						ac,
						&in_creds->session);
	if(ret)
	    goto out;
    }

    krb5_free_keyblock(context, ac->keyblock);
    ret = krb5_copy_keyblock(context, &in_creds->session, &ac->keyblock);
    if (ret)
	goto out;

    /* it's unclear what type of checksum we can use.  try the best one, except:
     * a) if it's configured differently for the current realm, or
     * b) if the session key is des-cbc-crc
     */

    if (in_data) {
	if(ac->keyblock->keytype == ETYPE_DES_CBC_CRC) {
	    /* this is to make DCE secd (and older MIT kdcs?) happy */
	    ret = krb5_create_checksum(context,
				       NULL,
				       0,
				       CKSUMTYPE_RSA_MD4,
				       in_data->data,
				       in_data->length,
				       &c);
	} else if(ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5 ||
		  ac->keyblock->keytype == ETYPE_ARCFOUR_HMAC_MD5_56 ||
		  ac->keyblock->keytype == ETYPE_DES_CBC_MD4 ||
		  ac->keyblock->keytype == ETYPE_DES_CBC_MD5) {
	    /* this is to make MS kdc happy */
	    ret = krb5_create_checksum(context,
				       NULL,
				       0,
				       CKSUMTYPE_RSA_MD5,
				       in_data->data,
				       in_data->length,
				       &c);
	} else {
	    krb5_crypto crypto;

	    ret = krb5_crypto_init(context, ac->keyblock, 0, &crypto);
	    if (ret)
		goto out;
	    ret = krb5_create_checksum(context,
				       crypto,
				       checksum_usage,
				       0,
				       in_data->data,
				       in_data->length,
				       &c);
	    krb5_crypto_destroy(context, crypto);
	}
	c_opt = &c;
    } else {
	c_opt = NULL;
    }

    if (ret)
	goto out;

    ret = _krb5_build_authenticator(context,
				    ac,
				    ac->keyblock->keytype,
				    in_creds,
				    c_opt,
				    &authenticator,
				    encrypt_usage);
    if (c_opt)
	free_Checksum (c_opt);
    if (ret)
	goto out;

    ret = krb5_build_ap_req (context, ac->keyblock->keytype,
			     in_creds, ap_req_options, authenticator, outbuf);
out:
    if(auth_context == NULL)
	krb5_auth_con_free(context, ac);
    return ret;
}
Beispiel #11
0
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_mk_rep(krb5_context context,
	    krb5_auth_context auth_context,
	    krb5_data *outbuf)
{
    krb5_error_code ret;
    AP_REP ap;
    EncAPRepPart body;
    u_char *buf = NULL;
    size_t buf_size;
    size_t len = 0;
    krb5_crypto crypto;

    ap.pvno = 5;
    ap.msg_type = krb_ap_rep;

    memset (&body, 0, sizeof(body));

    body.ctime = auth_context->authenticator->ctime;
    body.cusec = auth_context->authenticator->cusec;
    if (auth_context->flags & KRB5_AUTH_CONTEXT_USE_SUBKEY) {
	if (auth_context->local_subkey == NULL) {
	    ret = krb5_auth_con_generatelocalsubkey(context,
						    auth_context,
						    auth_context->keyblock);
	    if(ret) {
		free_EncAPRepPart(&body);
		return ret;
	    }
	}
	ret = krb5_copy_keyblock(context, auth_context->local_subkey,
				 &body.subkey);
	if (ret) {
	    free_EncAPRepPart(&body);
	    return krb5_enomem(context);
	}
    } else
	body.subkey = NULL;
    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
	if(auth_context->local_seqnumber == 0)
	    krb5_generate_seq_number (context,
				      auth_context->keyblock,
				      &auth_context->local_seqnumber);
	ALLOC(body.seq_number, 1);
	if (body.seq_number == NULL) {
	    free_EncAPRepPart(&body);
	    return krb5_enomem(context);
	}
	*(body.seq_number) = auth_context->local_seqnumber;
    } else
	body.seq_number = NULL;

    ap.enc_part.etype = auth_context->keyblock->keytype;
    ap.enc_part.kvno  = NULL;

    ASN1_MALLOC_ENCODE(EncAPRepPart, buf, buf_size, &body, &len, ret);
    free_EncAPRepPart (&body);
    if(ret)
	return ret;
    if (buf_size != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");
    ret = krb5_crypto_init(context, auth_context->keyblock,
			   0 /* ap.enc_part.etype */, &crypto);
    if (ret) {
	free (buf);
	return ret;
    }
    ret = krb5_encrypt (context,
			crypto,
			KRB5_KU_AP_REQ_ENC_PART,
			buf + buf_size - len,
			len,
			&ap.enc_part.cipher);
    krb5_crypto_destroy(context, crypto);
    free(buf);
    if (ret)
	return ret;

    ASN1_MALLOC_ENCODE(AP_REP, outbuf->data, outbuf->length, &ap, &len, ret);
    if (ret == 0 && outbuf->length != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");
    free_AP_REP (&ap);
    return ret;
}
Beispiel #12
0
krb5_error_code
_kdc_encode_reply(krb5_context context,
		  krb5_kdc_configuration *config,
		  KDC_REP *rep, const EncTicketPart *et, EncKDCRepPart *ek,
		  krb5_enctype etype,
		  int skvno, const EncryptionKey *skey,
		  int ckvno, const EncryptionKey *reply_key,
		  int rk_is_subkey,
		  const char **e_text,
		  krb5_data *reply)
{
    unsigned char *buf;
    size_t buf_size;
    size_t len = 0;
    krb5_error_code ret;
    krb5_crypto crypto;

    ASN1_MALLOC_ENCODE(EncTicketPart, buf, buf_size, et, &len, ret);
    if(ret) {
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "Failed to encode ticket: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }
    if(buf_size != len) {
	free(buf);
	kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
	*e_text = "KDC internal error";
	return KRB5KRB_ERR_GENERIC;
    }

    ret = krb5_crypto_init(context, skey, etype, &crypto);
    if (ret) {
        const char *msg;
	free(buf);
	msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }

    ret = krb5_encrypt_EncryptedData(context,
				     crypto,
				     KRB5_KU_TICKET,
				     buf,
				     len,
				     skvno,
				     &rep->ticket.enc_part);
    free(buf);
    krb5_crypto_destroy(context, crypto);
    if(ret) {
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "Failed to encrypt data: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }

    if(rep->msg_type == krb_as_rep && !config->encode_as_rep_as_tgs_rep)
	ASN1_MALLOC_ENCODE(EncASRepPart, buf, buf_size, ek, &len, ret);
    else
	ASN1_MALLOC_ENCODE(EncTGSRepPart, buf, buf_size, ek, &len, ret);
    if(ret) {
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "Failed to encode KDC-REP: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }
    if(buf_size != len) {
	free(buf);
	kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
	*e_text = "KDC internal error";
	return KRB5KRB_ERR_GENERIC;
    }
    ret = krb5_crypto_init(context, reply_key, 0, &crypto);
    if (ret) {
	const char *msg = krb5_get_error_message(context, ret);
	free(buf);
	kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }
    if(rep->msg_type == krb_as_rep) {
	krb5_encrypt_EncryptedData(context,
				   crypto,
				   KRB5_KU_AS_REP_ENC_PART,
				   buf,
				   len,
				   ckvno,
				   &rep->enc_part);
	free(buf);
	ASN1_MALLOC_ENCODE(AS_REP, buf, buf_size, rep, &len, ret);
    } else {
	krb5_encrypt_EncryptedData(context,
				   crypto,
				   rk_is_subkey ? KRB5_KU_TGS_REP_ENC_PART_SUB_KEY : KRB5_KU_TGS_REP_ENC_PART_SESSION,
				   buf,
				   len,
				   ckvno,
				   &rep->enc_part);
	free(buf);
	ASN1_MALLOC_ENCODE(TGS_REP, buf, buf_size, rep, &len, ret);
    }
    krb5_crypto_destroy(context, crypto);
    if(ret) {
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "Failed to encode KDC-REP: %s", msg);
	krb5_free_error_message(context, msg);
	return ret;
    }
    if(buf_size != len) {
	free(buf);
	kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
	*e_text = "KDC internal error";
	return KRB5KRB_ERR_GENERIC;
    }
    reply->data = buf;
    reply->length = buf_size;
    return 0;
}
Beispiel #13
0
OM_uint32 GSSAPI_CALLCONV
_gsskrb5_pseudo_random(OM_uint32 *minor_status,
		       gss_ctx_id_t context_handle,
		       int prf_key,
		       const gss_buffer_t prf_in,
		       ssize_t desired_output_len,
		       gss_buffer_t prf_out)
{
    gsskrb5_ctx ctx = (gsskrb5_ctx)context_handle;
    krb5_context context;
    krb5_error_code ret;
    krb5_crypto crypto;
    krb5_data input, output;
    uint32_t num;
    unsigned char *p;
    krb5_keyblock *key = NULL;

    if (ctx == NULL) {
	*minor_status = 0;
	return GSS_S_NO_CONTEXT;
    }

    if (desired_output_len <= 0) {
	*minor_status = 0;
	return GSS_S_FAILURE;
    }

    GSSAPI_KRB5_INIT (&context);

    switch(prf_key) {
    case GSS_C_PRF_KEY_FULL:
	_gsskrb5i_get_acceptor_subkey(ctx, context, &key);
	break;
    case GSS_C_PRF_KEY_PARTIAL:
	_gsskrb5i_get_initiator_subkey(ctx, context, &key);
	break;
    default:
	_gsskrb5_set_status(EINVAL, "unknown kerberos prf_key");
	*minor_status = EINVAL;
	return GSS_S_FAILURE;
    }

    if (key == NULL) {
	_gsskrb5_set_status(EINVAL, "no prf_key found");
	*minor_status = EINVAL;
	return GSS_S_FAILURE;
    }

    ret = krb5_crypto_init(context, key, 0, &crypto);
    krb5_free_keyblock (context, key);
    if (ret) {
	*minor_status = ret;
	return GSS_S_FAILURE;
    }

    prf_out->value = malloc(desired_output_len);
    if (prf_out->value == NULL) {
	_gsskrb5_set_status(GSS_KRB5_S_KG_INPUT_TOO_LONG, "Out of memory");
	*minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG;
	krb5_crypto_destroy(context, crypto);
	return GSS_S_FAILURE;
    }
    prf_out->length = desired_output_len;

    HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);

    input.length = prf_in->length + 4;
    input.data = malloc(prf_in->length + 4);
    if (input.data == NULL) {
	OM_uint32 junk;
	_gsskrb5_set_status(GSS_KRB5_S_KG_INPUT_TOO_LONG, "Out of memory");
	*minor_status = GSS_KRB5_S_KG_INPUT_TOO_LONG;
	gss_release_buffer(&junk, prf_out);
	krb5_crypto_destroy(context, crypto);
	HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
	return GSS_S_FAILURE;
    }
    memcpy(((unsigned char *)input.data) + 4, prf_in->value, prf_in->length);

    num = 0;
    p = prf_out->value;
    while(desired_output_len > 0) {
	_gsskrb5_encode_om_uint32(num, input.data);
	ret = krb5_crypto_prf(context, crypto, &input, &output);
	if (ret) {
	    OM_uint32 junk;
	    *minor_status = ret;
	    free(input.data);
	    gss_release_buffer(&junk, prf_out);
	    krb5_crypto_destroy(context, crypto);
	    HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
	    return GSS_S_FAILURE;
	}
	memcpy(p, output.data, min(desired_output_len, output.length));
	p += output.length;
	desired_output_len -= output.length;
	krb5_data_free(&output);
	num++;
    }
    free(input.data);

    krb5_crypto_destroy(context, crypto);

    HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);

    return GSS_S_COMPLETE;
}
Beispiel #14
0
static krb5_error_code
check_KRB5SignedPath(krb5_context context,
		     krb5_kdc_configuration *config,
		     hdb_entry_ex *krbtgt,
		     EncTicketPart *tkt,
		     KRB5SignedPathPrincipals **delegated,
		     int require_signedpath)
{
    krb5_error_code ret;
    krb5_data data;
    krb5_crypto crypto = NULL;

    *delegated = NULL;

    ret = find_KRB5SignedPath(context, tkt->authorization_data, &data);
    if (ret == 0) {
	KRB5SignedPathData spd;
	KRB5SignedPath sp;
	AuthorizationData *ad;
	size_t size;

	ret = decode_KRB5SignedPath(data.data, data.length, &sp, NULL);
	krb5_data_free(&data);
	if (ret)
	    return ret;

	spd.encticket = *tkt;
	/* the KRB5SignedPath is the last entry */
	ad = spd.encticket.authorization_data;
	if (--ad->len == 0)
	    spd.encticket.authorization_data = NULL;
	spd.delegated = sp.delegated;

	ASN1_MALLOC_ENCODE(KRB5SignedPathData, data.data, data.length,
			   &spd, &size, ret);
	ad->len++;
	spd.encticket.authorization_data = ad;
	if (ret) {
	    free_KRB5SignedPath(&sp);
	    return ret;
	}
	if (data.length != size)
	    krb5_abortx(context, "internal asn.1 encoder error");

	{
	    Key *key;
	    ret = hdb_enctype2key(context, &krbtgt->entry, sp.etype, &key);
	    if (ret == 0)
		ret = krb5_crypto_init(context, &key->key, 0, &crypto);
	    if (ret) {
		free(data.data);
		free_KRB5SignedPath(&sp);
		return ret;
	    }
	}
	ret = krb5_verify_checksum(context, crypto, KRB5_KU_KRB5SIGNEDPATH, 
				   data.data, data.length, 
				   &sp.cksum);
	krb5_crypto_destroy(context, crypto);
	free(data.data);
	if (ret) {
	    free_KRB5SignedPath(&sp);
	    return ret;
	}

	if (sp.delegated) {

	    *delegated = malloc(sizeof(*sp.delegated));
	    if (*delegated == NULL) {
		free_KRB5SignedPath(&sp);
		return ENOMEM;
	    }

	    ret = copy_KRB5SignedPathPrincipals(*delegated, sp.delegated);
	    if (ret) {
		free_KRB5SignedPath(&sp);
		free(*delegated);
		*delegated = NULL;
		return ret;
	    }
	}
	free_KRB5SignedPath(&sp);
	
    } else {
	if (require_signedpath)
	    return KRB5KDC_ERR_BADOPTION;
    }

    return 0;
}
Beispiel #15
0
krb5_error_code
_kdc_add_KRB5SignedPath(krb5_context context,
			krb5_kdc_configuration *config,
			hdb_entry_ex *krbtgt,
			krb5_enctype enctype,
			krb5_const_principal server,
			KRB5SignedPathPrincipals *principals,
			EncTicketPart *tkt)
{
    krb5_error_code ret;
    KRB5SignedPath sp;
    krb5_data data;
    krb5_crypto crypto = NULL;
    size_t size;

    if (server && principals) {
	ret = add_KRB5SignedPathPrincipals(principals, server);
	if (ret)
	    return ret;
    }

    {
	KRB5SignedPathData spd;
	
	spd.encticket = *tkt;
	spd.delegated = principals;
	
	ASN1_MALLOC_ENCODE(KRB5SignedPathData, data.data, data.length,
			   &spd, &size, ret);
	if (ret)
	    return ret;
	if (data.length != size)
	    krb5_abortx(context, "internal asn.1 encoder error");
    }

    {
	Key *key;
	ret = hdb_enctype2key(context, &krbtgt->entry, enctype, &key);
	if (ret == 0)
	    ret = krb5_crypto_init(context, &key->key, 0, &crypto);
	if (ret) {
	    free(data.data);
	    return ret;
	}
    }

    /*
     * Fill in KRB5SignedPath
     */

    sp.etype = enctype;
    sp.delegated = principals;

    ret = krb5_create_checksum(context, crypto, KRB5_KU_KRB5SIGNEDPATH, 0,
			       data.data, data.length, &sp.cksum);
    krb5_crypto_destroy(context, crypto);
    free(data.data);
    if (ret)
	return ret;

    ASN1_MALLOC_ENCODE(KRB5SignedPath, data.data, data.length, &sp, &size, ret);
    free_Checksum(&sp.cksum);
    if (ret)
	return ret;
    if (data.length != size)
	krb5_abortx(context, "internal asn.1 encoder error");

    
    /*
     * Add IF-RELEVANT(KRB5SignedPath) to the last slot in
     * authorization data field.
     */

    ret = _kdc_tkt_add_if_relevant_ad(context, tkt,
				      KRB5_AUTHDATA_SIGNTICKET, &data);
    krb5_data_free(&data);

    return ret;
}
Beispiel #16
0
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
_krb5_build_authenticator (krb5_context context,
			   krb5_auth_context auth_context,
			   krb5_enctype enctype,
			   krb5_creds *cred,
			   Checksum *cksum,
			   krb5_data *result,
			   krb5_key_usage usage)
{
    Authenticator auth;
    u_char *buf = NULL;
    size_t buf_size;
    size_t len = 0;
    krb5_error_code ret;
    krb5_crypto crypto;

    memset(&auth, 0, sizeof(auth));

    auth.authenticator_vno = 5;
    copy_Realm(&cred->client->realm, &auth.crealm);
    copy_PrincipalName(&cred->client->name, &auth.cname);

    krb5_us_timeofday (context, &auth.ctime, &auth.cusec);

    ret = krb5_auth_con_getlocalsubkey(context, auth_context, &auth.subkey);
    if(ret)
	goto fail;

    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
	if(auth_context->local_seqnumber == 0)
	    krb5_generate_seq_number (context,
				      &cred->session,
				      &auth_context->local_seqnumber);
	ALLOC(auth.seq_number, 1);
	if(auth.seq_number == NULL) {
	    ret = ENOMEM;
	    goto fail;
	}
	*auth.seq_number = auth_context->local_seqnumber;
    } else
	auth.seq_number = NULL;
    auth.authorization_data = NULL;

    if (cksum) {
	ALLOC(auth.cksum, 1);
	if (auth.cksum == NULL) {
	    ret = ENOMEM;
	    goto fail;
	}
	ret = copy_Checksum(cksum, auth.cksum);
	if (ret)
	    goto fail;

	if (auth.cksum->cksumtype == CKSUMTYPE_GSSAPI) {
	    /*
	     * This is not GSS-API specific, we only enable it for
	     * GSS for now
	     */
	    ret = make_etypelist(context, &auth.authorization_data);
	    if (ret)
		goto fail;
	}
    }

    /* XXX - Copy more to auth_context? */

    auth_context->authenticator->ctime = auth.ctime;
    auth_context->authenticator->cusec = auth.cusec;

    ASN1_MALLOC_ENCODE(Authenticator, buf, buf_size, &auth, &len, ret);
    if (ret)
	goto fail;
    if(buf_size != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");

    ret = krb5_crypto_init(context, &cred->session, enctype, &crypto);
    if (ret)
	goto fail;
    ret = krb5_encrypt (context,
			crypto,
			usage /* KRB5_KU_AP_REQ_AUTH */,
			buf,
			len,
			result);
    krb5_crypto_destroy(context, crypto);

    if (ret)
	goto fail;

 fail:
    free_Authenticator (&auth);
    free (buf);

    return ret;
}
Beispiel #17
0
static OM_uint32
gsskrb5_acceptor_start(OM_uint32 * minor_status,
		       gsskrb5_ctx ctx,
		       krb5_context context,
		       const gss_cred_id_t acceptor_cred_handle,
		       const gss_buffer_t input_token_buffer,
		       const gss_channel_bindings_t input_chan_bindings,
		       gss_name_t * src_name,
		       gss_OID * mech_type,
		       gss_buffer_t output_token,
		       OM_uint32 * ret_flags,
		       OM_uint32 * time_rec,
		       gss_cred_id_t * delegated_cred_handle)
{
    krb5_error_code kret;
    OM_uint32 ret = GSS_S_COMPLETE;
    krb5_data indata;
    krb5_flags ap_options;
    krb5_keytab keytab = NULL;
    int is_cfx = 0;
    const gsskrb5_cred acceptor_cred = (gsskrb5_cred)acceptor_cred_handle;

    /*
     * We may, or may not, have an escapsulation.
     */
    ret = _gsskrb5_decapsulate (minor_status,
				input_token_buffer,
				&indata,
				"\x01\x00",
				GSS_KRB5_MECHANISM);

    if (ret) {
	/* Assume that there is no OID wrapping. */
	indata.length	= input_token_buffer->length;
	indata.data	= input_token_buffer->value;
    }

    /*
     * We need to get our keytab
     */
    if (acceptor_cred == NULL) {
	if (_gsskrb5_keytab != NULL)
	    keytab = _gsskrb5_keytab;
    } else if (acceptor_cred->keytab != NULL) {
	keytab = acceptor_cred->keytab;
    }

    /*
     * We need to check the ticket and create the AP-REP packet
     */

    {
	krb5_rd_req_in_ctx in = NULL;
	krb5_rd_req_out_ctx out = NULL;
	krb5_principal server = NULL;

	if (acceptor_cred)
	    server = acceptor_cred->principal;

	kret = krb5_rd_req_in_ctx_alloc(context, &in);
	if (kret == 0)
	    kret = krb5_rd_req_in_set_keytab(context, in, keytab);
	if (kret) {
	    if (in)
		krb5_rd_req_in_ctx_free(context, in);
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	kret = krb5_rd_req_ctx(context,
			       &ctx->auth_context,
			       &indata,
			       server,
			       in, &out);
	krb5_rd_req_in_ctx_free(context, in);
	if (kret == KRB5KRB_AP_ERR_SKEW || kret == KRB5KRB_AP_ERR_TKT_NYV) {
	    /*
	     * No reply in non-MUTUAL mode, but we don't know that its
	     * non-MUTUAL mode yet, thats inside the 8003 checksum, so
	     * lets only send the error token on clock skew, that
	     * limit when send error token for non-MUTUAL.
	     */
	    return send_error_token(minor_status, context, kret,
				    server, &indata, output_token);
	} else if (kret) {
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	/*
	 * we need to remember some data on the context_handle.
	 */
	kret = krb5_rd_req_out_get_ap_req_options(context, out,
						  &ap_options);
	if (kret == 0)
	    kret = krb5_rd_req_out_get_ticket(context, out,
					      &ctx->ticket);
	if (kret == 0)
	    kret = krb5_rd_req_out_get_keyblock(context, out,
						&ctx->service_keyblock);
	ctx->lifetime = ctx->ticket->ticket.endtime;

	krb5_rd_req_out_ctx_free(context, out);
	if (kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}
    }


    /*
     * We need to copy the principal names to the context and the
     * calling layer.
     */
    kret = krb5_copy_principal(context,
			       ctx->ticket->client,
			       &ctx->source);
    if (kret) {
	ret = GSS_S_FAILURE;
	*minor_status = kret;
    }

    kret = krb5_copy_principal(context,
			       ctx->ticket->server,
			       &ctx->target);
    if (kret) {
	ret = GSS_S_FAILURE;
	*minor_status = kret;
	return ret;
    }

    /*
     * We need to setup some compat stuff, this assumes that
     * context_handle->target is already set.
     */
    ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
    if (ret)
	return ret;

    if (src_name != NULL) {
	kret = krb5_copy_principal (context,
				    ctx->ticket->client,
				    (gsskrb5_name*)src_name);
	if (kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}
    }

    /*
     * We need to get the flags out of the 8003 checksum.
     */

    {
	krb5_authenticator authenticator;

	kret = krb5_auth_con_getauthenticator(context,
					      ctx->auth_context,
					      &authenticator);
	if(kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}

	if (authenticator->cksum == NULL) {
	    krb5_free_authenticator(context, &authenticator);
	    *minor_status = 0;
	    return GSS_S_BAD_BINDINGS;
	}

        if (authenticator->cksum->cksumtype == CKSUMTYPE_GSSAPI) {
            ret = _gsskrb5_verify_8003_checksum(minor_status,
						input_chan_bindings,
						authenticator->cksum,
						&ctx->flags,
						&ctx->fwd_data);

	    krb5_free_authenticator(context, &authenticator);
	    if (ret) {
		return ret;
	    }
        } else {
	    krb5_crypto crypto;

	    kret = krb5_crypto_init(context,
				    ctx->auth_context->keyblock,
				    0, &crypto);
	    if(kret) {
		krb5_free_authenticator(context, &authenticator);

		ret = GSS_S_FAILURE;
		*minor_status = kret;
		return ret;
	    }

	    /*
	     * Windows accepts Samba3's use of a kerberos, rather than
	     * GSSAPI checksum here
	     */

	    kret = krb5_verify_checksum(context,
					crypto, KRB5_KU_AP_REQ_AUTH_CKSUM, NULL, 0,
					authenticator->cksum);
	    krb5_free_authenticator(context, &authenticator);
	    krb5_crypto_destroy(context, crypto);

	    if(kret) {
		ret = GSS_S_BAD_SIG;
		*minor_status = kret;
		return ret;
	    }

	    /*
	     * Samba style get some flags (but not DCE-STYLE), use
	     * ap_options to guess the mutual flag.
	     */
 	    ctx->flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
	    if (ap_options & AP_OPTS_MUTUAL_REQUIRED)
		ctx->flags |= GSS_C_MUTUAL_FLAG;
        }
    }

    if(ctx->flags & GSS_C_MUTUAL_FLAG) {
	krb5_data outbuf;
	int use_subkey = 0;

	_gsskrb5i_is_cfx(context, ctx, 1);
	is_cfx = (ctx->more_flags & IS_CFX);

	if (is_cfx || (ap_options & AP_OPTS_USE_SUBKEY)) {
	    use_subkey = 1;
	} else {
	    krb5_keyblock *rkey;

	    /*
	     * If there is a initiator subkey, copy that to acceptor
	     * subkey to match Windows behavior
	     */
	    kret = krb5_auth_con_getremotesubkey(context,
						 ctx->auth_context,
						 &rkey);
	    if (kret == 0) {
		kret = krb5_auth_con_setlocalsubkey(context,
						    ctx->auth_context,
						    rkey);
		if (kret == 0)
		    use_subkey = 1;
		krb5_free_keyblock(context, rkey);
	    }
	}
	if (use_subkey) {
	    ctx->more_flags |= ACCEPTOR_SUBKEY;
	    krb5_auth_con_addflags(context, ctx->auth_context,
				   KRB5_AUTH_CONTEXT_USE_SUBKEY,
				   NULL);
	}

	kret = krb5_mk_rep(context,
			   ctx->auth_context,
			   &outbuf);
	if (kret) {
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	if (IS_DCE_STYLE(ctx)) {
	    output_token->length = outbuf.length;
	    output_token->value = outbuf.data;
	} else {
	    ret = _gsskrb5_encapsulate(minor_status,
				       &outbuf,
				       output_token,
				       "\x02\x00",
				       GSS_KRB5_MECHANISM);
	    krb5_data_free (&outbuf);
	    if (ret)
		return ret;
	}
    }

    ctx->flags |= GSS_C_TRANS_FLAG;

    /* Remember the flags */

    ctx->lifetime = ctx->ticket->ticket.endtime;
    ctx->more_flags |= OPEN;

    if (mech_type)
	*mech_type = GSS_KRB5_MECHANISM;

    if (time_rec) {
	ret = _gsskrb5_lifetime_left(minor_status,
				     context,
				     ctx->lifetime,
				     time_rec);
	if (ret) {
	    return ret;
	}
    }

    /*
     * When GSS_C_DCE_STYLE is in use, we need ask for a AP-REP from
     * the client.
     */
    if (IS_DCE_STYLE(ctx)) {
	/*
	 * Return flags to caller, but we haven't processed
	 * delgations yet
	 */
	if (ret_flags)
	    *ret_flags = (ctx->flags & ~GSS_C_DELEG_FLAG);

	ctx->state = ACCEPTOR_WAIT_FOR_DCESTYLE;
	return GSS_S_CONTINUE_NEEDED;
    }

    ret = gsskrb5_acceptor_ready(minor_status, ctx, context,
				 delegated_cred_handle);

    if (ret_flags)
	*ret_flags = ctx->flags;

    return ret;
}
Beispiel #18
0
krb5_error_code
_kdc_do_524(krb5_context context,
	    krb5_kdc_configuration *config,
	    const Ticket *t, krb5_data *reply,
	    const char *from, struct sockaddr *addr)
{
    krb5_error_code ret = 0;
    krb5_crypto crypto;
    hdb_entry_ex *server = NULL;
    Key *skey;
    krb5_data et_data;
    EncTicketPart et;
    EncryptedData ticket;
    krb5_storage *sp;
    char *spn = NULL;
    unsigned char buf[MAX_KTXT_LEN + 4 * 4];
    size_t len;
    int kvno = 0;

    if(!config->enable_524) {
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Rejected ticket conversion request from %s", from);
	goto out;
    }

    ret = fetch_server (context, config, t, &spn, &server, from);
    if (ret) {
	goto out;
    }

    ret = hdb_enctype2key(context, &server->entry, t->enc_part.etype, &skey);
    if(ret){
	kdc_log(context, config, 0,
		"No suitable key found for server (%s) from %s", spn, from);
	goto out;
    }
    ret = krb5_crypto_init(context, &skey->key, 0, &crypto);
    if (ret) {
	kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
		krb5_get_err_text(context, ret));
	goto out;
    }
    ret = krb5_decrypt_EncryptedData (context,
				      crypto,
				      KRB5_KU_TICKET,
				      &t->enc_part,
				      &et_data);
    krb5_crypto_destroy(context, crypto);
    if(ret){
	kdc_log(context, config, 0,
		"Failed to decrypt ticket from %s for %s", from, spn);
	goto out;
    }
    ret = krb5_decode_EncTicketPart(context, et_data.data, et_data.length,
				    &et, &len);
    krb5_data_free(&et_data);
    if(ret){
	kdc_log(context, config, 0,
		"Failed to decode ticket from %s for %s", from, spn);
	goto out;
    }

    ret = log_524 (context, config, &et, from, spn);
    if (ret) {
	free_EncTicketPart(&et);
	goto out;
    }

    ret = verify_flags (context, config, &et, spn);
    if (ret) {
	free_EncTicketPart(&et);
	goto out;
    }

    ret = set_address (context, config, &et, addr, from);
    if (ret) {
	free_EncTicketPart(&et);
	goto out;
    }

    ret = encode_524_response(context, config, spn, et, t,
			      server, &ticket, &kvno);
    free_EncTicketPart(&et);

 out:
    /* make reply */
    memset(buf, 0, sizeof(buf));
    sp = krb5_storage_from_mem(buf, sizeof(buf));
    if (sp) {
	krb5_store_int32(sp, ret);
	if(ret == 0){
	    krb5_store_int32(sp, kvno);
	    krb5_store_data(sp, ticket.cipher);
	    /* Aargh! This is coded as a KTEXT_ST. */
	    krb5_storage_seek(sp, MAX_KTXT_LEN - ticket.cipher.length, SEEK_CUR);
	    krb5_store_int32(sp, 0); /* mbz */
	    free_EncryptedData(&ticket);
	}
	ret = krb5_storage_to_data(sp, reply);
	reply->length = krb5_storage_seek(sp, 0, SEEK_CUR);
	krb5_storage_free(sp);
    } else
	krb5_data_zero(reply);
    if(spn)
	free(spn);
    if(server)
	_kdc_free_ent (context, server);
    return ret;
}
Beispiel #19
0
krb5_error_code KRB5_LIB_FUNCTION
krb5_get_forwarded_creds (krb5_context	    context,
			  krb5_auth_context auth_context,
			  krb5_ccache       ccache,
			  krb5_flags        flags,
			  const char        *hostname,
			  krb5_creds        *in_creds,
			  krb5_data         *out_data)
{
    krb5_error_code ret;
    krb5_creds *out_creds;
    krb5_addresses addrs, *paddrs;
    KRB_CRED cred;
    KrbCredInfo *krb_cred_info;
    EncKrbCredPart enc_krb_cred_part;
    size_t len;
    unsigned char *buf;
    size_t buf_size;
    krb5_kdc_flags kdc_flags;
    krb5_crypto crypto;
    struct addrinfo *ai;
    int save_errno;
    krb5_creds *ticket;
    char *realm;

    if (in_creds->client && in_creds->client->realm)
	realm = in_creds->client->realm;
    else
	realm = in_creds->server->realm;

    addrs.len = 0;
    addrs.val = NULL;
    paddrs = &addrs;

    /*
     * If tickets are address-less, forward address-less tickets.
     */

    ret = _krb5_get_krbtgt (context,
			    ccache,
			    realm,
			    &ticket);
    if(ret == 0) {
	if (ticket->addresses.len == 0)
	    paddrs = NULL;
	krb5_free_creds (context, ticket);
    }
    
    if (paddrs != NULL) {

	ret = getaddrinfo (hostname, NULL, NULL, &ai);
	if (ret) {
	    save_errno = errno;
	    krb5_set_error_string(context, "resolving %s: %s",
				  hostname, gai_strerror(ret));
	    return krb5_eai_to_heim_errno(ret, save_errno);
	}
	
	ret = add_addrs (context, &addrs, ai);
	freeaddrinfo (ai);
	if (ret)
	    return ret;
    }
    
    kdc_flags.b = int2KDCOptions(flags);

    ret = krb5_get_kdc_cred (context,
			     ccache,
			     kdc_flags,
			     paddrs,
			     NULL,
			     in_creds,
			     &out_creds);
    krb5_free_addresses (context, &addrs);
    if (ret) {
	return ret;
    }

    memset (&cred, 0, sizeof(cred));
    cred.pvno = 5;
    cred.msg_type = krb_cred;
    ALLOC_SEQ(&cred.tickets, 1);
    if (cred.tickets.val == NULL) {
	ret = ENOMEM;
	krb5_set_error_string(context, "malloc: out of memory");
	goto out2;
    }
    ret = decode_Ticket(out_creds->ticket.data,
			out_creds->ticket.length,
			cred.tickets.val, &len);
    if (ret)
	goto out3;

    memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
    ALLOC_SEQ(&enc_krb_cred_part.ticket_info, 1);
    if (enc_krb_cred_part.ticket_info.val == NULL) {
	ret = ENOMEM;
	krb5_set_error_string(context, "malloc: out of memory");
	goto out4;
    }
    
    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
	krb5_timestamp sec;
	int32_t usec;
	
	krb5_us_timeofday (context, &sec, &usec);
	
	ALLOC(enc_krb_cred_part.timestamp, 1);
	if (enc_krb_cred_part.timestamp == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_string(context, "malloc: out of memory");
	    goto out4;
	}
	*enc_krb_cred_part.timestamp = sec;
	ALLOC(enc_krb_cred_part.usec, 1);
	if (enc_krb_cred_part.usec == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_string(context, "malloc: out of memory");
	    goto out4;
	}
	*enc_krb_cred_part.usec      = usec;
    } else {
	enc_krb_cred_part.timestamp = NULL;
	enc_krb_cred_part.usec = NULL;
    }

    if (auth_context->local_address && auth_context->local_port) {
	krb5_boolean noaddr;
	krb5_const_realm realm;

	realm = krb5_principal_get_realm(context, out_creds->server);
	krb5_appdefault_boolean(context, NULL, realm, "no-addresses", paddrs == NULL,
				&noaddr);
	if (!noaddr) {
	    ret = krb5_make_addrport (context,
				      &enc_krb_cred_part.s_address,
				      auth_context->local_address,
				      auth_context->local_port);
	    if (ret)
		goto out4;
	}
    }

    if (auth_context->remote_address) {
	if (auth_context->remote_port) {
	    krb5_boolean noaddr;
	    krb5_const_realm realm;

	    realm = krb5_principal_get_realm(context, out_creds->server);
	    /* Is this correct, and should we use the paddrs == NULL
               trick here as well? Having an address-less ticket may
               indicate that we don't know our own global address, but
               it does not necessary mean that we don't know the
               server's. */
	    krb5_appdefault_boolean(context, NULL, realm, "no-addresses",
				    FALSE, &noaddr);
	    if (!noaddr) {
		ret = krb5_make_addrport (context,
					  &enc_krb_cred_part.r_address,
					  auth_context->remote_address,
					  auth_context->remote_port);
		if (ret)
		    goto out4;
	    }
	} else {
	    ALLOC(enc_krb_cred_part.r_address, 1);
	    if (enc_krb_cred_part.r_address == NULL) {
		ret = ENOMEM;
		krb5_set_error_string(context, "malloc: out of memory");
		goto out4;
	    }

	    ret = krb5_copy_address (context, auth_context->remote_address,
				     enc_krb_cred_part.r_address);
	    if (ret)
		goto out4;
	}
    }

    /* fill ticket_info.val[0] */

    enc_krb_cred_part.ticket_info.len = 1;

    krb_cred_info = enc_krb_cred_part.ticket_info.val;

    copy_EncryptionKey (&out_creds->session, &krb_cred_info->key);
    ALLOC(krb_cred_info->prealm, 1);
    copy_Realm (&out_creds->client->realm, krb_cred_info->prealm);
    ALLOC(krb_cred_info->pname, 1);
    copy_PrincipalName(&out_creds->client->name, krb_cred_info->pname);
    ALLOC(krb_cred_info->flags, 1);
    *krb_cred_info->flags          = out_creds->flags.b;
    ALLOC(krb_cred_info->authtime, 1);
    *krb_cred_info->authtime       = out_creds->times.authtime;
    ALLOC(krb_cred_info->starttime, 1);
    *krb_cred_info->starttime      = out_creds->times.starttime;
    ALLOC(krb_cred_info->endtime, 1);
    *krb_cred_info->endtime        = out_creds->times.endtime;
    ALLOC(krb_cred_info->renew_till, 1);
    *krb_cred_info->renew_till = out_creds->times.renew_till;
    ALLOC(krb_cred_info->srealm, 1);
    copy_Realm (&out_creds->server->realm, krb_cred_info->srealm);
    ALLOC(krb_cred_info->sname, 1);
    copy_PrincipalName (&out_creds->server->name, krb_cred_info->sname);
    ALLOC(krb_cred_info->caddr, 1);
    copy_HostAddresses (&out_creds->addresses, krb_cred_info->caddr);

    krb5_free_creds (context, out_creds);

    /* encode EncKrbCredPart */

    ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size, 
		       &enc_krb_cred_part, &len, ret);
    free_EncKrbCredPart (&enc_krb_cred_part);
    if (ret) {
	free_KRB_CRED(&cred);
	return ret;
    }
    if(buf_size != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");

    if (auth_context->flags & KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED) {
	cred.enc_part.etype = ENCTYPE_NULL;
	cred.enc_part.kvno = NULL;
	cred.enc_part.cipher.data = buf;
	cred.enc_part.cipher.length = buf_size;
    } else {
	krb5_keyblock *key;

	if (auth_context->local_subkey)
	    key = auth_context->local_subkey;
	else if (auth_context->remote_subkey)
	    key = auth_context->remote_subkey;
	else
	    key = auth_context->keyblock;
	
	ret = krb5_crypto_init(context, key, 0, &crypto);
	if (ret) {
	    free(buf);
	    free_KRB_CRED(&cred);
	    return ret;
	}
	ret = krb5_encrypt_EncryptedData (context,
					  crypto,
					  KRB5_KU_KRB_CRED,
					  buf,
					  len,
					  0,
					  &cred.enc_part);
	free(buf);
	krb5_crypto_destroy(context, crypto);
	if (ret) {
	    free_KRB_CRED(&cred);
	    return ret;
	}
    }

    ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret);
    free_KRB_CRED (&cred);
    if (ret)
	return ret;
    if(buf_size != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");
    out_data->length = len;
    out_data->data   = buf;
    return 0;
 out4:
    free_EncKrbCredPart(&enc_krb_cred_part);
 out3:
    free_KRB_CRED(&cred);
 out2:
    krb5_free_creds (context, out_creds);
    return ret;
}
Beispiel #20
0
static OM_uint32
gsskrb5_acceptor_start(OM_uint32 * minor_status,
		       gsskrb5_ctx ctx,
		       krb5_context context,
		       const gss_cred_id_t acceptor_cred_handle,
		       const gss_buffer_t input_token_buffer,
		       const gss_channel_bindings_t input_chan_bindings,
		       gss_name_t * src_name,
		       gss_OID * mech_type,
		       gss_buffer_t output_token,
		       OM_uint32 * ret_flags,
		       OM_uint32 * time_rec,
		       gss_cred_id_t * delegated_cred_handle)
{
    krb5_error_code kret;
    OM_uint32 ret = GSS_S_COMPLETE;
    krb5_data indata;
    krb5_flags ap_options;
    krb5_keytab keytab = NULL;
    int is_cfx = 0;
    const gsskrb5_cred acceptor_cred = (gsskrb5_cred)acceptor_cred_handle;
    krb5_boolean is_hostbased_service = FALSE;

    /*
     * We may, or may not, have an escapsulation.
     */
    ret = _gsskrb5_decapsulate (minor_status,
				input_token_buffer,
				&indata,
				"\x01\x00",
				ctx->mech);

    if (ret) {
	/* Assume that there is no OID wrapping. */
	indata.length	= input_token_buffer->length;
	indata.data	= input_token_buffer->value;
    }

    /*
     * We need to get our keytab
     */
    if (acceptor_cred == NULL) {
	if (_gsskrb5_keytab != NULL)
	    keytab = _gsskrb5_keytab;
    } else if (acceptor_cred->keytab != NULL) {
	keytab = acceptor_cred->keytab;
    }

    is_hostbased_service = 
	(acceptor_cred &&
	 acceptor_cred->principal &&
	 krb5_principal_is_gss_hostbased_service(context, acceptor_cred->principal));

    /*
     * We need to check the ticket and create the AP-REP packet
     */

    {
	krb5_rd_req_in_ctx in = NULL;
	krb5_rd_req_out_ctx out = NULL;
	krb5_principal server = NULL;

	if (acceptor_cred && !is_hostbased_service)
	    server = acceptor_cred->principal;

	kret = krb5_rd_req_in_ctx_alloc(context, &in);
	if (kret == 0)
	    kret = krb5_rd_req_in_set_keytab(context, in, keytab);
	if (kret) {
	    if (in)
		krb5_rd_req_in_ctx_free(context, in);
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	kret = krb5_rd_req_ctx(context,
			       &ctx->auth_context,
			       &indata,
			       server,
			       in, &out);
	krb5_rd_req_in_ctx_free(context, in);
	if (ret && _gss_mg_log_level(5)) {
	    const char *e = krb5_get_error_message(context, ret);
	    char *s = NULL;
	    if (server)
		(void)krb5_unparse_name(context, server, &s);
	    _gss_mg_log(5, "gss-asc: rd_req (server: %s) failed with: %d: %s",
			s ? s : "<not specified>",
			ret, e);
	    krb5_free_error_message(context, e);
	    if (s)
		krb5_xfree(s);
	}


	switch (kret) {
	case 0:
	    break;
	case KRB5KRB_AP_ERR_SKEW:
	case KRB5KRB_AP_ERR_TKT_NYV:
	    /*
	     * No reply in non-MUTUAL mode, but we don't know that its
	     * non-MUTUAL mode yet, thats inside the 8003 checksum, so
	     * lets only send the error token on clock skew, that
	     * limit when send error token for non-MUTUAL.
	     */
	    return send_error_token(minor_status, context, kret,
				    server, &indata, ctx->mech, output_token);
	case KRB5KRB_AP_ERR_MODIFIED:
	case KRB5_KT_NOTFOUND:
	case KRB5_KT_END:
	    /*
	     * If the error is on the keytab entry missing or bad
	     * decryption, lets assume that the keytab version was
	     * wrong and tell the client that.
	     */
	    return send_error_token(minor_status, context, KRB5KRB_AP_ERR_MODIFIED,
				    server, NULL, ctx->mech, output_token);
	default:
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	/*
	 * we need to remember some data on the context_handle.
	 */
	kret = krb5_rd_req_out_get_ap_req_options(context, out,
						  &ap_options);
	if (kret == 0)
	    kret = krb5_rd_req_out_get_ticket(context, out,
					      &ctx->ticket);
	if (kret == 0)
	    kret = krb5_rd_req_out_get_keyblock(context, out,
						&ctx->service_keyblock);
	if (kret == 0) {
	    int flags;
	    flags = krb5_rd_req_out_get_flags(context, out);
	    if (flags & KRB5_RD_REQ_OUT_PAC_VALID)
		ctx->more_flags |= PAC_VALID;
	}
	if (kret == 0 && is_hostbased_service) {
	    krb5_principal sp = ctx->ticket->server;

	    if (sp->name.name_string.len < 1 ||
		strcmp(sp->name.name_string.val[0], acceptor_cred->principal->name.name_string.val[0]) != 0)
	    {
		kret = KRB5KRB_AP_WRONG_PRINC;
		krb5_set_error_message(context, ret, "Expecting service %s but got %s",
				       acceptor_cred->principal->name.name_string.val[0],
				       sp->name.name_string.val[0]);
	    }
	}

	ctx->endtime = ctx->ticket->ticket.endtime;

	krb5_rd_req_out_ctx_free(context, out);
	if (kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}
    }


    /*
     * We need to copy the principal names to the context and the
     * calling layer.
     */
    kret = krb5_copy_principal(context,
			       ctx->ticket->client,
			       &ctx->source);
    if (kret) {
	*minor_status = kret;
	return GSS_S_FAILURE;
    }

    kret = krb5_copy_principal(context,
			       ctx->ticket->server,
			       &ctx->target);
    if (kret) {
	ret = GSS_S_FAILURE;
	*minor_status = kret;
	return ret;
    }

    /*
     * We need to setup some compat stuff, this assumes that
     * context_handle->target is already set.
     */
    ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
    if (ret)
	return ret;

    if (src_name != NULL) {
	kret = krb5_copy_principal (context,
				    ctx->ticket->client,
				    (gsskrb5_name*)src_name);
	if (kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}
    }

    /*
     * We need to get the flags out of the 8003 checksum.
     */

    {
	krb5_authenticator authenticator;

	kret = krb5_auth_con_getauthenticator(context,
					      ctx->auth_context,
					      &authenticator);
	if(kret) {
	    ret = GSS_S_FAILURE;
	    *minor_status = kret;
	    return ret;
	}

	if (authenticator->cksum == NULL) {
	    krb5_free_authenticator(context, &authenticator);
	    *minor_status = 0;
	    return GSS_S_BAD_BINDINGS;
	}

        if (authenticator->cksum->cksumtype == CKSUMTYPE_GSSAPI) {
	    krb5_data finished_data;
	    krb5_crypto crypto = NULL;

	    if (ctx->auth_context->remote_subkey) {
		kret = krb5_crypto_init(context,
					ctx->auth_context->remote_subkey,
					0, &crypto);
		if (kret) {
		    *minor_status = kret;
		    return GSS_S_FAILURE;
		}
	    }

	    krb5_data_zero(&finished_data);

            ret = _gsskrb5_verify_8003_checksum(minor_status,
						context,
						crypto,
						input_chan_bindings,
						authenticator->cksum,
						&ctx->flags,
						&ctx->fwd_data,
						&finished_data);

	    krb5_free_authenticator(context, &authenticator);
	    if (ret) {
		krb5_crypto_destroy(context, crypto);
		return ret;
	    }

	    if (finished_data.length) {
		GSS_KRB5_FINISHED finished;
		krb5_data pkt;

		memset(&finished, 0, sizeof(finished));

		if (ctx->messages == NULL) {
		    krb5_crypto_destroy(context, crypto);
		    krb5_data_free(&finished_data);
		    *minor_status = 0;
		    return GSS_S_BAD_SIG;
		}

		kret = krb5_storage_to_data(ctx->messages, &pkt);
		if (kret) {
		    krb5_crypto_destroy(context, crypto);
		    krb5_data_free(&finished_data);
		    *minor_status = kret;
		    return GSS_S_FAILURE;
		}

		if (ctx->auth_context->remote_subkey == NULL) {
		    krb5_crypto_destroy(context, crypto);
		    krb5_data_free(&finished_data);
		    krb5_data_free(&pkt);
		    *minor_status = 0;
		    return GSS_S_BAD_SIG;
		}

		kret = decode_GSS_KRB5_FINISHED(finished_data.data,
						finished_data.length,
						&finished, NULL);
		krb5_data_free(&finished_data);
		if (kret) {
		    krb5_crypto_destroy(context, crypto);
		    krb5_data_free(&pkt);
		    *minor_status = kret;
		    return GSS_S_FAILURE;
		}

		kret = krb5_verify_checksum(context, crypto,
					    KRB5_KU_FINISHED,
					    pkt.data, pkt.length,
					    &finished.gss_mic);
		free_GSS_KRB5_FINISHED(&finished);
		krb5_data_free(&pkt);
		if (kret) {
		    krb5_crypto_destroy(context, crypto);
		    *minor_status = kret;
		    return GSS_S_FAILURE;
		}
	    }
	    krb5_crypto_destroy(context, crypto);

        } else {
	    krb5_crypto crypto;

	    kret = krb5_crypto_init(context,
				    ctx->auth_context->keyblock,
				    0, &crypto);
	    if(kret) {
		krb5_free_authenticator(context, &authenticator);

		ret = GSS_S_FAILURE;
		*minor_status = kret;
		return ret;
	    }

	    /*
	     * Windows accepts Samba3's use of a kerberos, rather than
	     * GSSAPI checksum here
	     */

	    kret = krb5_verify_checksum(context,
					crypto, KRB5_KU_AP_REQ_AUTH_CKSUM, NULL, 0,
					authenticator->cksum);
	    krb5_free_authenticator(context, &authenticator);
	    krb5_crypto_destroy(context, crypto);

	    if(kret) {
		ret = GSS_S_BAD_SIG;
		*minor_status = kret;
		return ret;
	    }

	    /*
	     * Samba style get some flags (but not DCE-STYLE), use
	     * ap_options to guess the mutual flag.
	     */
 	    ctx->flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
	    if (ap_options & AP_OPTS_MUTUAL_REQUIRED)
		ctx->flags |= GSS_C_MUTUAL_FLAG;
        }
    }

    if(ctx->flags & GSS_C_MUTUAL_FLAG) {
	krb5_data outbuf;
	int use_subkey = 0;

	_gsskrb5i_is_cfx(context, ctx, 1);
	is_cfx = (ctx->more_flags & IS_CFX);

	if (is_cfx || (ap_options & AP_OPTS_USE_SUBKEY)) {
	    use_subkey = 1;
	} else {
	    krb5_keyblock *rkey;

	    /*
	     * If there is a initiator subkey, copy that to acceptor
	     * subkey to match Windows behavior
	     */
	    kret = krb5_auth_con_getremotesubkey(context,
						 ctx->auth_context,
						 &rkey);
	    if (kret == 0) {
		kret = krb5_auth_con_setlocalsubkey(context,
						    ctx->auth_context,
						    rkey);
		if (kret == 0)
		    use_subkey = 1;
		krb5_free_keyblock(context, rkey);
	    }
	}
	if (use_subkey) {
	    ctx->gk5c.flags |= GK5C_ACCEPTOR_SUBKEY;
	    krb5_auth_con_addflags(context, ctx->auth_context,
				   KRB5_AUTH_CONTEXT_USE_SUBKEY,
				   NULL);
	}

	kret = krb5_mk_rep(context,
			   ctx->auth_context,
			   &outbuf);
	if (kret) {
	    *minor_status = kret;
	    return GSS_S_FAILURE;
	}

	if (IS_DCE_STYLE(ctx)) {
	    output_token->length = outbuf.length;
	    output_token->value = outbuf.data;
	} else {
	    ret = _gsskrb5_encapsulate(minor_status,
				       &outbuf,
				       output_token,
				       "\x02\x00",
				       ctx->mech);
	    krb5_data_free (&outbuf);
	    if (ret)
		return ret;
	}
    }

    ctx->flags |= GSS_C_TRANS_FLAG;

    /* Remember the flags */

    ctx->endtime = ctx->ticket->ticket.endtime;
    ctx->more_flags |= OPEN;

    if (mech_type)
	*mech_type = ctx->mech;

    if (time_rec) {
	ret = _gsskrb5_lifetime_left(minor_status,
				     context,
				     ctx->endtime,
				     time_rec);
	if (ret) {
	    return ret;
	}
    }

    /*
     * When GSS_C_DCE_STYLE is in use, we need ask for a AP-REP from
     * the client.
     */
    if (IS_DCE_STYLE(ctx)) {
	/*
	 * Return flags to caller, but we haven't processed
	 * delgations yet
	 */
	if (ret_flags)
	    *ret_flags = (ctx->flags & ~GSS_C_DELEG_FLAG);

	ctx->acceptor_state = acceptor_wait_for_dcestyle;
	return GSS_S_CONTINUE_NEEDED;
    }

    ret = gsskrb5_acceptor_ready(minor_status, ctx, context,
				 delegated_cred_handle);

    if (ret_flags)
	*ret_flags = ctx->flags;

    return ret;
}
Beispiel #21
0
static krb5_error_code
tgs_build_reply(krb5_context context, 
		krb5_kdc_configuration *config,
		KDC_REQ *req, 
		KDC_REQ_BODY *b,
		hdb_entry_ex *krbtgt,
		krb5_enctype krbtgt_etype,
		krb5_ticket *ticket,
		krb5_data *reply,
		const char *from,
		const char **e_text,
		AuthorizationData *auth_data,
		const struct sockaddr *from_addr,
		int datagram_reply)
{
    krb5_error_code ret;
    krb5_principal cp = NULL, sp = NULL;
    krb5_principal client_principal = NULL;
    char *spn = NULL, *cpn = NULL;
    hdb_entry_ex *server = NULL, *client = NULL;
    EncTicketPart *tgt = &ticket->ticket;
    KRB5SignedPathPrincipals *spp = NULL;
    const EncryptionKey *ekey;
    krb5_keyblock sessionkey;
    krb5_kvno kvno;
    krb5_data rspac;
    int cross_realm = 0;

    PrincipalName *s;
    Realm r;
    int nloop = 0;
    EncTicketPart adtkt;
    char opt_str[128];
    int require_signedpath = 0;

    memset(&sessionkey, 0, sizeof(sessionkey));
    memset(&adtkt, 0, sizeof(adtkt));
    krb5_data_zero(&rspac);

    s = b->sname;
    r = b->realm;

    if(b->kdc_options.enc_tkt_in_skey){
	Ticket *t;
	hdb_entry_ex *uu;
	krb5_principal p;
	Key *uukey;
	    
	if(b->additional_tickets == NULL || 
	   b->additional_tickets->len == 0){
	    ret = KRB5KDC_ERR_BADOPTION; /* ? */
	    kdc_log(context, config, 0,
		    "No second ticket present in request");
	    goto out;
	}
	t = &b->additional_tickets->val[0];
	if(!get_krbtgt_realm(&t->sname)){
	    kdc_log(context, config, 0,
		    "Additional ticket is not a ticket-granting ticket");
	    ret = KRB5KDC_ERR_POLICY;
	    goto out;
	}
	_krb5_principalname2krb5_principal(context, &p, t->sname, t->realm);
	ret = _kdc_db_fetch(context, config, p, 
			    HDB_F_GET_CLIENT|HDB_F_GET_SERVER, 
			    NULL, &uu);
	krb5_free_principal(context, p);
	if(ret){
	    if (ret == HDB_ERR_NOENTRY)
		ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
	    goto out;
	}
	ret = hdb_enctype2key(context, &uu->entry, 
			      t->enc_part.etype, &uukey);
	if(ret){
	    _kdc_free_ent(context, uu);
	    ret = KRB5KDC_ERR_ETYPE_NOSUPP; /* XXX */
	    goto out;
	}
	ret = krb5_decrypt_ticket(context, t, &uukey->key, &adtkt, 0);
	_kdc_free_ent(context, uu);
	if(ret)
	    goto out;

	ret = verify_flags(context, config, &adtkt, spn);
	if (ret)
	    goto out;

	s = &adtkt.cname;
	r = adtkt.crealm;
    }

    _krb5_principalname2krb5_principal(context, &sp, *s, r);
    ret = krb5_unparse_name(context, sp, &spn);	
    if (ret)
	goto out;
    _krb5_principalname2krb5_principal(context, &cp, tgt->cname, tgt->crealm);
    ret = krb5_unparse_name(context, cp, &cpn);
    if (ret)
	goto out;
    unparse_flags (KDCOptions2int(b->kdc_options),
		   asn1_KDCOptions_units(),
		   opt_str, sizeof(opt_str));
    if(*opt_str)
	kdc_log(context, config, 0,
		"TGS-REQ %s from %s for %s [%s]", 
		cpn, from, spn, opt_str);
    else
	kdc_log(context, config, 0,
		"TGS-REQ %s from %s for %s", cpn, from, spn);

    /*
     * Fetch server
     */

server_lookup:
    ret = _kdc_db_fetch(context, config, sp, HDB_F_GET_SERVER, NULL, &server);

    if(ret){
	const char *new_rlm;
	Realm req_rlm;
	krb5_realm *realms;

	if ((req_rlm = get_krbtgt_realm(&sp->name)) != NULL) {
	    if(nloop++ < 2) {
		new_rlm = find_rpath(context, tgt->crealm, req_rlm);
		if(new_rlm) {
		    kdc_log(context, config, 5, "krbtgt for realm %s "
			    "not found, trying %s", 
			    req_rlm, new_rlm);
		    krb5_free_principal(context, sp);
		    free(spn);
		    krb5_make_principal(context, &sp, r, 
					KRB5_TGS_NAME, new_rlm, NULL);
		    ret = krb5_unparse_name(context, sp, &spn);	
		    if (ret)
			goto out;
		    goto server_lookup;
		}
	    }
	} else if(need_referral(context, sp, &realms)) {
	    if (strcmp(realms[0], sp->realm) != 0) {
		kdc_log(context, config, 5,
			"Returning a referral to realm %s for "
			"server %s that was not found",
			realms[0], spn);
		krb5_free_principal(context, sp);
		free(spn);
		krb5_make_principal(context, &sp, r, KRB5_TGS_NAME,
				    realms[0], NULL);
		ret = krb5_unparse_name(context, sp, &spn);
		if (ret)
		    goto out;
		krb5_free_host_realm(context, realms);
		goto server_lookup;
	    }
	    krb5_free_host_realm(context, realms);
	}
	kdc_log(context, config, 0,
		"Server not found in database: %s: %s", spn,
		krb5_get_err_text(context, ret));
	if (ret == HDB_ERR_NOENTRY)
	    ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
	goto out;
    }

    ret = _kdc_db_fetch(context, config, cp, HDB_F_GET_CLIENT, NULL, &client);
    if(ret) {
	const char *krbtgt_realm; 

	/*
	 * If the client belongs to the same realm as our krbtgt, it
	 * should exist in the local database.
	 *
	 */

	krbtgt_realm = 
	    krb5_principal_get_comp_string(context, 
					   krbtgt->entry.principal, 1);

	if(strcmp(krb5_principal_get_realm(context, cp), krbtgt_realm) == 0) {
	    if (ret == HDB_ERR_NOENTRY)
		ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	    kdc_log(context, config, 1, "Client no longer in database: %s",
		    cpn);
	    goto out;
	}
	
	kdc_log(context, config, 1, "Client not found in database: %s: %s",
		cpn, krb5_get_err_text(context, ret));

	cross_realm = 1;
    }
    
    /*
     * Check that service is in the same realm as the krbtgt. If its
     * not the same, its someone that is using a uni-directional trust
     * backward.
     */
    
    if (strcmp(krb5_principal_get_realm(context, sp),
	       krb5_principal_get_comp_string(context, 
					      krbtgt->entry.principal, 
					      1)) != 0) {
	char *tpn;
	ret = krb5_unparse_name(context, krbtgt->entry.principal, &tpn);
	kdc_log(context, config, 0,
		"Request with wrong krbtgt: %s",
		(ret == 0) ? tpn : "<unknown>");
	if(ret == 0)
	    free(tpn);
	ret = KRB5KRB_AP_ERR_NOT_US;
	goto out;
    }

    /*
     *
     */

    client_principal = cp;

    if (client) {
	const PA_DATA *sdata;
	int i = 0;

	sdata = _kdc_find_padata(req, &i, KRB5_PADATA_S4U2SELF);
	if (sdata) {
	    krb5_crypto crypto;
	    krb5_data datack;
	    PA_S4U2Self self;
	    char *selfcpn = NULL;
	    const char *str;

	    ret = decode_PA_S4U2Self(sdata->padata_value.data, 
				     sdata->padata_value.length,
				     &self, NULL);
	    if (ret) {
		kdc_log(context, config, 0, "Failed to decode PA-S4U2Self");
		goto out;
	    }

	    ret = _krb5_s4u2self_to_checksumdata(context, &self, &datack);
	    if (ret)
		goto out;

	    ret = krb5_crypto_init(context, &tgt->key, 0, &crypto);
	    if (ret) {
		free_PA_S4U2Self(&self);
		krb5_data_free(&datack);
		kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
			krb5_get_err_text(context, ret));
		goto out;
	    }

	    ret = krb5_verify_checksum(context,
				       crypto,
				       KRB5_KU_OTHER_CKSUM,
				       datack.data, 
				       datack.length, 
				       &self.cksum);
	    krb5_data_free(&datack);
	    krb5_crypto_destroy(context, crypto);
	    if (ret) {
		free_PA_S4U2Self(&self);
		kdc_log(context, config, 0, 
			"krb5_verify_checksum failed for S4U2Self: %s",
			krb5_get_err_text(context, ret));
		goto out;
	    }

	    ret = _krb5_principalname2krb5_principal(context,
						     &client_principal,
						     self.name,
						     self.realm);
	    free_PA_S4U2Self(&self);
	    if (ret)
		goto out;

	    ret = krb5_unparse_name(context, client_principal, &selfcpn);	
	    if (ret)
		goto out;

	    /*
	     * Check that service doing the impersonating is
	     * requesting a ticket to it-self.
	     */
	    if (krb5_principal_compare(context, cp, sp) != TRUE) {
		kdc_log(context, config, 0, "S4U2Self: %s is not allowed "
			"to impersonate some other user "
			"(tried for user %s to service %s)",
			cpn, selfcpn, spn);
		free(selfcpn);
		ret = KRB5KDC_ERR_BADOPTION; /* ? */
		goto out;
	    }

	    /*
	     * If the service isn't trusted for authentication to
	     * delegation, remove the forward flag.
	     */

	    if (client->entry.flags.trusted_for_delegation) {
		str = "[forwardable]";
	    } else {
		b->kdc_options.forwardable = 0;
		str = "";
	    }
	    kdc_log(context, config, 0, "s4u2self %s impersonating %s to "
		    "service %s %s", cpn, selfcpn, spn, str);
	    free(selfcpn);
	}
    }

    /*
     * Constrained delegation
     */

    if (client != NULL
	&& b->additional_tickets != NULL
	&& b->additional_tickets->len != 0
	&& b->kdc_options.enc_tkt_in_skey == 0)
    {
	Key *clientkey;
	Ticket *t;
	char *str;

	t = &b->additional_tickets->val[0];

	ret = hdb_enctype2key(context, &client->entry, 
			      t->enc_part.etype, &clientkey);
	if(ret){
	    ret = KRB5KDC_ERR_ETYPE_NOSUPP; /* XXX */
	    goto out;
	}

	ret = krb5_decrypt_ticket(context, t, &clientkey->key, &adtkt, 0);
	if (ret) {
	    kdc_log(context, config, 0,
		    "failed to decrypt ticket for "
		    "constrained delegation from %s to %s ", spn, cpn);
	    goto out;
	}

	/* check that ticket is valid */

	if (adtkt.flags.forwardable == 0) {
	    kdc_log(context, config, 0,
		    "Missing forwardable flag on ticket for "
		    "constrained delegation from %s to %s ", spn, cpn);
	    ret = KRB5KDC_ERR_ETYPE_NOSUPP; /* XXX */
	    goto out;
	}

	ret = check_constrained_delegation(context, config, client, sp);
	if (ret) {
	    kdc_log(context, config, 0,
		    "constrained delegation from %s to %s not allowed", 
		    spn, cpn);
	    goto out;
	}

	ret = _krb5_principalname2krb5_principal(context,
						 &client_principal,
						 adtkt.cname,
						 adtkt.crealm);
	if (ret)
	    goto out;

	ret = krb5_unparse_name(context, client_principal, &str);
	if (ret)
	    goto out;

	ret = verify_flags(context, config, &adtkt, str);
	if (ret) {
	    free(str);
	    goto out;
	}

	/*
	 * Check KRB5SignedPath in authorization data and add new entry to
	 * make sure servers can't fake a ticket to us.
	 */

	ret = check_KRB5SignedPath(context,
				   config,
				   krbtgt,
				   &adtkt,
				   &spp,
				   1);
	if (ret) {
	    kdc_log(context, config, 0,
		    "KRB5SignedPath check from service %s failed "
		    "for delegation to %s for client %s "
		    "from %s failed with %s",
		    spn, str, cpn, from, krb5_get_err_text(context, ret));
	    free(str);
	    goto out;
	}

	kdc_log(context, config, 0, "constrained delegation for %s "
		"from %s to %s", str, cpn, spn);
	free(str);

	/* 
	 * Also require that the KDC have issue the service's krbtgt
	 * used to do the request. 
	 */
	require_signedpath = 1;
    }

    /*
     * Check flags
     */

    ret = _kdc_check_flags(context, config, 
			   client, cpn,
			   server, spn,
			   FALSE);
    if(ret)
	goto out;

    if((b->kdc_options.validate || b->kdc_options.renew) && 
       !krb5_principal_compare(context, 
			       krbtgt->entry.principal,
			       server->entry.principal)){
	kdc_log(context, config, 0, "Inconsistent request.");
	ret = KRB5KDC_ERR_SERVER_NOMATCH;
	goto out;
    }

    /* check for valid set of addresses */
    if(!_kdc_check_addresses(context, config, tgt->caddr, from_addr)) {
	ret = KRB5KRB_AP_ERR_BADADDR;
	kdc_log(context, config, 0, "Request from wrong address");
	goto out;
    }
	
    /*
     * Select enctype, return key and kvno.
     */

    {
	krb5_enctype etype;

	if(b->kdc_options.enc_tkt_in_skey) {
	    int i;
	    ekey = &adtkt.key;
	    for(i = 0; i < b->etype.len; i++)
		if (b->etype.val[i] == adtkt.key.keytype)
		    break;
	    if(i == b->etype.len) {
		krb5_clear_error_string(context);
		return KRB5KDC_ERR_ETYPE_NOSUPP;
	    }
	    etype = b->etype.val[i];
	    kvno = 0;
	} else {
	    Key *skey;
	    
	    ret = _kdc_find_etype(context, server, b->etype.val, b->etype.len,
				  &skey, &etype);
	    if(ret) {
		kdc_log(context, config, 0, 
			"Server (%s) has no support for etypes", spp);
		return ret;
	    }
	    ekey = &skey->key;
	    kvno = server->entry.kvno;
	}
	
	ret = krb5_generate_random_keyblock(context, etype, &sessionkey);
	if (ret)
	    goto out;
    }

    /* check PAC if not cross realm and if there is one */
    if (!cross_realm) {
	Key *tkey;

	ret = hdb_enctype2key(context, &krbtgt->entry, 
			      krbtgt_etype, &tkey);
	if(ret) {
	    kdc_log(context, config, 0,
		    "Failed to find key for krbtgt PAC check");
	    goto out;
	}

	ret = check_PAC(context, config, client_principal, 
			client, server, ekey, &tkey->key,
			tgt, &rspac, &require_signedpath);
	if (ret) {
	    kdc_log(context, config, 0,
		    "Verify PAC failed for %s (%s) from %s with %s",
		    spn, cpn, from, krb5_get_err_text(context, ret));
	    goto out;
	}
    }

    /* also check the krbtgt for signature */
    ret = check_KRB5SignedPath(context,
			       config,
			       krbtgt,
			       tgt,
			       &spp,
			       require_signedpath);
    if (ret) {
	kdc_log(context, config, 0,
		"KRB5SignedPath check failed for %s (%s) from %s with %s",
		spn, cpn, from, krb5_get_err_text(context, ret));
	goto out;
    }

    /*
     *
     */

    ret = tgs_make_reply(context,
			 config, 
			 b, 
			 client_principal,
			 tgt, 
			 ekey,
			 &sessionkey,
			 kvno,
			 auth_data,
			 server, 
			 spn,
			 client, 
			 cp, 
			 krbtgt, 
			 krbtgt_etype,
			 spp,
			 &rspac,
			 e_text,
			 reply);
	
out:
    free(spn);
    free(cpn);
	    
    krb5_data_free(&rspac);
    krb5_free_keyblock_contents(context, &sessionkey);
    if(server)
	_kdc_free_ent(context, server);
    if(client)
	_kdc_free_ent(context, client);

    if (client_principal && client_principal != cp)
	krb5_free_principal(context, client_principal);
    if (cp)
	krb5_free_principal(context, cp);
    if (sp)
	krb5_free_principal(context, sp);

    free_EncTicketPart(&adtkt);

    return ret;
}
Beispiel #22
0
static OM_uint32
verify_mic_des3
           (OM_uint32 * minor_status,
            const gsskrb5_ctx context_handle,
	    krb5_context context,
            const gss_buffer_t message_buffer,
            const gss_buffer_t token_buffer,
            gss_qop_t * qop_state,
	    krb5_keyblock *key,
	    char *type
	    )
{
  u_char *p;
  u_char *seq;
  uint32_t seq_number;
  OM_uint32 ret;
  krb5_crypto crypto;
  krb5_data seq_data;
  int cmp, docompat;
  Checksum csum;
  char *tmp;
  char ivec[8];

  p = token_buffer->value;
  ret = _gsskrb5_verify_header (&p,
				   token_buffer->length,
				   type,
				   GSS_KRB5_MECHANISM);
  if (ret)
      return ret;

  if (memcmp(p, "\x04\x00", 2) != 0) /* SGN_ALG = HMAC SHA1 DES3-KD */
      return GSS_S_BAD_SIG;
  p += 2;
  if (memcmp (p, "\xff\xff\xff\xff", 4) != 0)
    return GSS_S_BAD_MIC;
  p += 4;

  ret = krb5_crypto_init(context, key,
			 ETYPE_DES3_CBC_NONE, &crypto);
  if (ret){
      *minor_status = ret;
      return GSS_S_FAILURE;
  }

  /* verify sequence number */
  docompat = 0;
retry:
  if (docompat)
      memset(ivec, 0, 8);
  else
      memcpy(ivec, p + 8, 8);

  ret = krb5_decrypt_ivec (context,
			   crypto,
			   KRB5_KU_USAGE_SEQ,
			   p, 8, &seq_data, ivec);
  if (ret) {
      if (docompat++) {
	  krb5_crypto_destroy (context, crypto);
	  *minor_status = ret;
	  return GSS_S_FAILURE;
      } else
	  goto retry;
  }

  if (seq_data.length != 8) {
      krb5_data_free (&seq_data);
      if (docompat++) {
	  krb5_crypto_destroy (context, crypto);
	  return GSS_S_BAD_MIC;
      } else
	  goto retry;
  }

  HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);

  seq = seq_data.data;
  _gsskrb5_decode_om_uint32(seq, &seq_number);

  if (context_handle->more_flags & LOCAL)
      cmp = ct_memcmp(&seq[4], "\xff\xff\xff\xff", 4);
  else
      cmp = ct_memcmp(&seq[4], "\x00\x00\x00\x00", 4);

  krb5_data_free (&seq_data);
  if (cmp != 0) {
      krb5_crypto_destroy (context, crypto);
      *minor_status = 0;
      HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
      return GSS_S_BAD_MIC;
  }

  ret = _gssapi_msg_order_check(context_handle->order, seq_number);
  if (ret) {
      krb5_crypto_destroy (context, crypto);
      *minor_status = 0;
      HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
      return ret;
  }

  /* verify checksum */

  tmp = malloc (message_buffer->length + 8);
  if (tmp == NULL) {
      krb5_crypto_destroy (context, crypto);
      HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
      *minor_status = ENOMEM;
      return GSS_S_FAILURE;
  }

  memcpy (tmp, p - 8, 8);
  memcpy (tmp + 8, message_buffer->value, message_buffer->length);

  csum.cksumtype = CKSUMTYPE_HMAC_SHA1_DES3;
  csum.checksum.length = 20;
  csum.checksum.data   = p + 8;

  ret = krb5_verify_checksum (context, crypto,
			      KRB5_KU_USAGE_SIGN,
			      tmp, message_buffer->length + 8,
			      &csum);
  free (tmp);
  if (ret) {
      krb5_crypto_destroy (context, crypto);
      *minor_status = ret;
      HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
      return GSS_S_BAD_MIC;
  }
  HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);

  krb5_crypto_destroy (context, crypto);
  return GSS_S_COMPLETE;
}
Beispiel #23
0
static krb5_error_code
tgs_check_authenticator(krb5_context context, 
			krb5_kdc_configuration *config,
	                krb5_auth_context ac,
			KDC_REQ_BODY *b, 
			const char **e_text,
			krb5_keyblock *key)
{
    krb5_authenticator auth;
    size_t len;
    unsigned char *buf;
    size_t buf_size;
    krb5_error_code ret;
    krb5_crypto crypto;
    
    krb5_auth_con_getauthenticator(context, ac, &auth);
    if(auth->cksum == NULL){
	kdc_log(context, config, 0, "No authenticator in request");
	ret = KRB5KRB_AP_ERR_INAPP_CKSUM;
	goto out;
    }
    /*
     * according to RFC1510 it doesn't need to be keyed,
     * but according to the latest draft it needs to.
     */
    if (
#if 0
!krb5_checksum_is_keyed(context, auth->cksum->cksumtype)
	||
#endif
 !krb5_checksum_is_collision_proof(context, auth->cksum->cksumtype)) {
	kdc_log(context, config, 0, "Bad checksum type in authenticator: %d", 
		auth->cksum->cksumtype);
	ret =  KRB5KRB_AP_ERR_INAPP_CKSUM;
	goto out;
    }
		
    /* XXX should not re-encode this */
    ASN1_MALLOC_ENCODE(KDC_REQ_BODY, buf, buf_size, b, &len, ret);
    if(ret){
	kdc_log(context, config, 0, "Failed to encode KDC-REQ-BODY: %s", 
		krb5_get_err_text(context, ret));
	goto out;
    }
    if(buf_size != len) {
	free(buf);
	kdc_log(context, config, 0, "Internal error in ASN.1 encoder");
	*e_text = "KDC internal error";
	ret = KRB5KRB_ERR_GENERIC;
	goto out;
    }
    ret = krb5_crypto_init(context, key, 0, &crypto);
    if (ret) {
	free(buf);
	kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
		krb5_get_err_text(context, ret));
	goto out;
    }
    ret = krb5_verify_checksum(context,
			       crypto,
			       KRB5_KU_TGS_REQ_AUTH_CKSUM,
			       buf, 
			       len,
			       auth->cksum);
    free(buf);
    krb5_crypto_destroy(context, crypto);
    if(ret){
	kdc_log(context, config, 0,
		"Failed to verify authenticator checksum: %s", 
		krb5_get_err_text(context, ret));
    }
out:
    free_Authenticator(auth);
    free(auth);
    return ret;
}
Beispiel #24
0
krb5_error_code KRB5_LIB_FUNCTION
krb5_rd_rep(krb5_context context,
	    krb5_auth_context auth_context,
	    const krb5_data *inbuf,
	    krb5_ap_rep_enc_part **repl)
{
    krb5_error_code ret;
    AP_REP ap_rep;
    size_t len;
    krb5_data data;
    krb5_crypto crypto;

    krb5_data_zero (&data);
    ret = 0;

    ret = decode_AP_REP(inbuf->data, inbuf->length, &ap_rep, &len);
    if (ret)
	return ret;
    if (ap_rep.pvno != 5) {
	ret = KRB5KRB_AP_ERR_BADVERSION;
	krb5_clear_error_message (context);
	goto out;
    }
    if (ap_rep.msg_type != krb_ap_rep) {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_message (context);
	goto out;
    }

    ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto);
    if (ret)
	goto out;
    ret = krb5_decrypt_EncryptedData (context,
				      crypto,	
				      KRB5_KU_AP_REQ_ENC_PART,
				      &ap_rep.enc_part,
				      &data);
    krb5_crypto_destroy(context, crypto);
    if (ret)
	goto out;

    *repl = malloc(sizeof(**repl));
    if (*repl == NULL) {
	ret = ENOMEM;
	krb5_set_error_message(context, ret, N_("malloc: out of memory", ""));
	goto out;
    }
    ret = krb5_decode_EncAPRepPart(context,
				   data.data,
				   data.length,
				   *repl,
				   &len);
    if (ret)
	return ret;

    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
	if ((*repl)->ctime != auth_context->authenticator->ctime ||
	    (*repl)->cusec != auth_context->authenticator->cusec)
	{
	    krb5_free_ap_rep_enc_part(context, *repl);
	    *repl = NULL;
	    ret = KRB5KRB_AP_ERR_MUT_FAIL;
	    krb5_clear_error_message (context);
	    goto out;
	}
    }
    if ((*repl)->seq_number)
	krb5_auth_con_setremoteseqnumber(context, auth_context,
					 *((*repl)->seq_number));
    if ((*repl)->subkey)
	krb5_auth_con_setremotesubkey(context, auth_context, (*repl)->subkey);

 out:
    krb5_data_free (&data);
    free_AP_REP (&ap_rep);
    return ret;
}
Beispiel #25
0
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_cred(krb5_context context,
	     krb5_auth_context auth_context,
	     krb5_data *in_data,
	     krb5_creds ***ret_creds,
	     krb5_replay_data *outdata)
{
    krb5_error_code ret;
    size_t len;
    KRB_CRED cred;
    EncKrbCredPart enc_krb_cred_part;
    krb5_data enc_krb_cred_part_data;
    krb5_crypto crypto;
    int i;

    memset(&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));

    if ((auth_context->flags &
	 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
	outdata == NULL)
	return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */

    *ret_creds = NULL;

    ret = decode_KRB_CRED(in_data->data, in_data->length,
			  &cred, &len);
    if(ret) {
	krb5_clear_error_message(context);
	return ret;
    }

    if (cred.pvno != 5) {
	ret = KRB5KRB_AP_ERR_BADVERSION;
	krb5_clear_error_message (context);
	goto out;
    }

    if (cred.msg_type != krb_cred) {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_message (context);
	goto out;
    }

    if (cred.enc_part.etype == ETYPE_NULL) {
	/* DK: MIT GSS-API Compatibility */
	enc_krb_cred_part_data.length = cred.enc_part.cipher.length;
	enc_krb_cred_part_data.data   = cred.enc_part.cipher.data;
    } else {
	/* Try both subkey and session key.
	 *
	 * RFC4120 claims we should use the session key, but Heimdal
	 * before 0.8 used the remote subkey if it was send in the
	 * auth_context.
	 */

	if (auth_context->remote_subkey) {
	    ret = krb5_crypto_init(context, auth_context->remote_subkey,
				   0, &crypto);
	    if (ret)
		goto out;

	    ret = krb5_decrypt_EncryptedData(context,
					     crypto,
					     KRB5_KU_KRB_CRED,
					     &cred.enc_part,
					     &enc_krb_cred_part_data);
	
	    krb5_crypto_destroy(context, crypto);
	}

	/*
	 * If there was not subkey, or we failed using subkey,
	 * retry using the session key
	 */
	if (auth_context->remote_subkey == NULL || ret == KRB5KRB_AP_ERR_BAD_INTEGRITY)
	{

	    ret = krb5_crypto_init(context, auth_context->keyblock,
				   0, &crypto);

	    if (ret)
		goto out;
	
	    ret = krb5_decrypt_EncryptedData(context,
					     crypto,
					     KRB5_KU_KRB_CRED,
					     &cred.enc_part,
					     &enc_krb_cred_part_data);
	
	    krb5_crypto_destroy(context, crypto);
	}
	if (ret)
	    goto out;
    }

    ret = decode_EncKrbCredPart(enc_krb_cred_part_data.data,
				enc_krb_cred_part_data.length,
				&enc_krb_cred_part,
				&len);
    if (enc_krb_cred_part_data.data != cred.enc_part.cipher.data)
	krb5_data_free(&enc_krb_cred_part_data);
    if (ret) {
	krb5_set_error_message(context, ret,
			       N_("Failed to decode "
				  "encrypte credential part", ""));
	goto out;
    }

    /* check sender address */

    if (enc_krb_cred_part.s_address
	&& auth_context->remote_address
	&& auth_context->remote_port) {
	krb5_address *a;

	ret = krb5_make_addrport (context, &a,
				  auth_context->remote_address,
				  auth_context->remote_port);
	if (ret)
	    goto out;


	ret = compare_addrs(context, a, enc_krb_cred_part.s_address,
			    N_("sender address is wrong "
			       "in received creds", ""));
	krb5_free_address(context, a);
	free(a);
	if(ret)
	    goto out;
    }

    /* check receiver address */

    if (enc_krb_cred_part.r_address
	&& auth_context->local_address) {
	if(auth_context->local_port &&
	   enc_krb_cred_part.r_address->addr_type == KRB5_ADDRESS_ADDRPORT) {
	    krb5_address *a;
	    ret = krb5_make_addrport (context, &a,
				      auth_context->local_address,
				      auth_context->local_port);
	    if (ret)
		goto out;
	
	    ret = compare_addrs(context, a, enc_krb_cred_part.r_address,
				N_("receiver address is wrong "
				   "in received creds", ""));
	    krb5_free_address(context, a);
	    free(a);
	    if(ret)
		goto out;
	} else {
	    ret = compare_addrs(context, auth_context->local_address,
				enc_krb_cred_part.r_address,
				N_("receiver address is wrong "
				   "in received creds", ""));
	    if(ret)
		goto out;
	}
    }

    /* check timestamp */
    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
	krb5_timestamp sec;

	krb5_timeofday (context, &sec);

	if (enc_krb_cred_part.timestamp == NULL ||
	    enc_krb_cred_part.usec      == NULL ||
	    abs(*enc_krb_cred_part.timestamp - sec)
	    > context->max_skew) {
	    krb5_clear_error_message (context);
	    ret = KRB5KRB_AP_ERR_SKEW;
	    goto out;
	}
    }

    if ((auth_context->flags &
	 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE))) {
	/* if these fields are not present in the cred-part, silently
           return zero */
	memset(outdata, 0, sizeof(*outdata));
	if(enc_krb_cred_part.timestamp)
	    outdata->timestamp = *enc_krb_cred_part.timestamp;
	if(enc_krb_cred_part.usec)
	    outdata->usec = *enc_krb_cred_part.usec;
	if(enc_krb_cred_part.nonce)
	    outdata->seq = *enc_krb_cred_part.nonce;
    }

    /* Convert to NULL terminated list of creds */

    *ret_creds = calloc(enc_krb_cred_part.ticket_info.len + 1,
			sizeof(**ret_creds));

    if (*ret_creds == NULL) {
	ret = ENOMEM;
	krb5_set_error_message(context, ret,
			       N_("malloc: out of memory", ""));
	goto out;
    }

    for (i = 0; i < enc_krb_cred_part.ticket_info.len; ++i) {
	KrbCredInfo *kci = &enc_krb_cred_part.ticket_info.val[i];
	krb5_creds *creds;

	creds = calloc(1, sizeof(*creds));
	if(creds == NULL) {
	    ret = ENOMEM;
	    krb5_set_error_message(context, ret,
				   N_("malloc: out of memory", ""));
	    goto out;
	}

	ASN1_MALLOC_ENCODE(Ticket, creds->ticket.data, creds->ticket.length,
			   &cred.tickets.val[i], &len, ret);
	if (ret) {
	    free(creds);
	    goto out;
	}
	if(creds->ticket.length != len)
	    krb5_abortx(context, "internal error in ASN.1 encoder");
	copy_EncryptionKey (&kci->key, &creds->session);
	if (kci->prealm && kci->pname)
	    _krb5_principalname2krb5_principal (context,
						&creds->client,
						*kci->pname,
						*kci->prealm);
	if (kci->flags)
	    creds->flags.b = *kci->flags;
	if (kci->authtime)
	    creds->times.authtime = *kci->authtime;
	if (kci->starttime)
	    creds->times.starttime = *kci->starttime;
	if (kci->endtime)
	    creds->times.endtime = *kci->endtime;
	if (kci->renew_till)
	    creds->times.renew_till = *kci->renew_till;
	if (kci->srealm && kci->sname)
	    _krb5_principalname2krb5_principal (context,
						&creds->server,
						*kci->sname,
						*kci->srealm);
	if (kci->caddr)
	    krb5_copy_addresses (context,
				 kci->caddr,
				 &creds->addresses);
	
	(*ret_creds)[i] = creds;
	
    }
    (*ret_creds)[i] = NULL;

    free_KRB_CRED (&cred);
    free_EncKrbCredPart(&enc_krb_cred_part);

    return 0;

  out:
    free_EncKrbCredPart(&enc_krb_cred_part);
    free_KRB_CRED (&cred);
    if(*ret_creds) {
	for(i = 0; (*ret_creds)[i]; i++)
	    krb5_free_creds(context, (*ret_creds)[i]);
	free(*ret_creds);
	*ret_creds = NULL;
    }
    return ret;
}
Beispiel #26
0
krb5_error_code
_kdc_pk_mk_pa_reply(krb5_context context,
		    krb5_kdc_configuration *config,
		    pk_client_params *cp,
		    const hdb_entry_ex *client,
		    krb5_enctype sessionetype,
		    const KDC_REQ *req,
		    const krb5_data *req_buffer,
		    krb5_keyblock *reply_key,
		    krb5_keyblock *sessionkey,
		    METHOD_DATA *md)
{
    krb5_error_code ret;
    void *buf = NULL;
    size_t len = 0, size = 0;
    krb5_enctype enctype;
    int pa_type;
    hx509_cert kdc_cert = NULL;
    size_t i;

    if (!config->enable_pkinit) {
	krb5_clear_error_message(context);
	return 0;
    }

    if (req->req_body.etype.len > 0) {
	for (i = 0; i < req->req_body.etype.len; i++)
	    if (krb5_enctype_valid(context, req->req_body.etype.val[i]) == 0)
		break;
	if (req->req_body.etype.len <= i) {
	    ret = KRB5KRB_ERR_GENERIC;
	    krb5_set_error_message(context, ret,
				   "No valid enctype available from client");
	    goto out;
	}
	enctype = req->req_body.etype.val[i];
    } else
	enctype = ETYPE_DES3_CBC_SHA1;

    if (cp->type == PKINIT_27) {
	PA_PK_AS_REP rep;
	const char *type, *other = "";

	memset(&rep, 0, sizeof(rep));

	pa_type = KRB5_PADATA_PK_AS_REP;

	if (cp->keyex == USE_RSA) {
	    ContentInfo info;

	    type = "enckey";

	    rep.element = choice_PA_PK_AS_REP_encKeyPack;

	    ret = krb5_generate_random_keyblock(context, enctype,
						&cp->reply_key);
	    if (ret) {
		free_PA_PK_AS_REP(&rep);
		goto out;
	    }
	    ret = pk_mk_pa_reply_enckey(context,
					config,
					cp,
					req,
					req_buffer,
					&cp->reply_key,
					&info,
					&kdc_cert);
	    if (ret) {
		free_PA_PK_AS_REP(&rep);
		goto out;
	    }
	    ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
			       rep.u.encKeyPack.length, &info, &size,
			       ret);
	    free_ContentInfo(&info);
	    if (ret) {
		krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
				       "failed %d", ret);
		free_PA_PK_AS_REP(&rep);
		goto out;
	    }
	    if (rep.u.encKeyPack.length != size)
		krb5_abortx(context, "Internal ASN.1 encoder error");

	    ret = krb5_generate_random_keyblock(context, sessionetype,
						sessionkey);
	    if (ret) {
		free_PA_PK_AS_REP(&rep);
		goto out;
	    }

	} else {
	    ContentInfo info;

	    switch (cp->keyex) {
	    case USE_DH: type = "dh"; break;
	    case USE_ECDH: type = "ecdh"; break;
	    default: krb5_abortx(context, "unknown keyex"); break;
	    }

	    if (cp->dh_group_name)
		other = cp->dh_group_name;

	    rep.element = choice_PA_PK_AS_REP_dhInfo;

	    ret = generate_dh_keyblock(context, cp, enctype);
	    if (ret)
		return ret;

	    ret = pk_mk_pa_reply_dh(context, config,
				    cp,
				    &info,
				    &kdc_cert);
	    if (ret) {
		free_PA_PK_AS_REP(&rep);
		krb5_set_error_message(context, ret,
				       "create pa-reply-dh "
				       "failed %d", ret);
		goto out;
	    }

	    ASN1_MALLOC_ENCODE(ContentInfo, rep.u.dhInfo.dhSignedData.data,
			       rep.u.dhInfo.dhSignedData.length, &info, &size,
			       ret);
	    free_ContentInfo(&info);
	    if (ret) {
		krb5_set_error_message(context, ret,
				       "encoding of Key ContentInfo "
				       "failed %d", ret);
		free_PA_PK_AS_REP(&rep);
		goto out;
	    }
	    if (rep.u.encKeyPack.length != size)
		krb5_abortx(context, "Internal ASN.1 encoder error");

	    /* generate the session key using the method from RFC6112 */
	    {
		krb5_keyblock kdc_contribution_key;
		krb5_crypto reply_crypto;
		krb5_crypto kdccont_crypto;
		krb5_data p1 = { strlen("PKINIT"), "PKINIT"};
		krb5_data p2 = { strlen("KEYEXCHANGE"), "KEYEXCHANGE"};
		void *kckdata;
		size_t kcklen;
		EncryptedData kx;
		void *kxdata;
		size_t kxlen;

		ret = krb5_generate_random_keyblock(context, sessionetype,
						&kdc_contribution_key);
		if (ret) {
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		ret = krb5_crypto_init(context, &cp->reply_key, enctype, &reply_crypto);
		if (ret) {
		    krb5_free_keyblock_contents(context, &kdc_contribution_key);
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		ret = krb5_crypto_init(context, &kdc_contribution_key, sessionetype, &kdccont_crypto);
		if (ret) {
		    krb5_crypto_destroy(context, reply_crypto);
		    krb5_free_keyblock_contents(context, &kdc_contribution_key);
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		/* KRB-FX-CF2 */
		ret = krb5_crypto_fx_cf2(context, kdccont_crypto, reply_crypto,
					 &p1, &p2, sessionetype, sessionkey);
		krb5_crypto_destroy(context, kdccont_crypto);
		if (ret) {
		    krb5_crypto_destroy(context, reply_crypto);
		    krb5_free_keyblock_contents(context, &kdc_contribution_key);
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		ASN1_MALLOC_ENCODE(EncryptionKey, kckdata, kcklen,
				   &kdc_contribution_key, &size, ret);
		krb5_free_keyblock_contents(context, &kdc_contribution_key);
		if (ret) {
		    krb5_set_error_message(context, ret, "encoding of PKINIT-KX Key failed %d", ret);
		    krb5_crypto_destroy(context, reply_crypto);
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		if (kcklen != size)
		    krb5_abortx(context, "Internal ASN.1 encoder error");
		ret = krb5_encrypt_EncryptedData(context, reply_crypto, KRB5_KU_PA_PKINIT_KX,
					kckdata, kcklen, 0, &kx);
		krb5_crypto_destroy(context, reply_crypto);
		free(kckdata);
		if (ret) {
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		ASN1_MALLOC_ENCODE(EncryptedData, kxdata, kxlen,
				   &kx, &size, ret);
		free_EncryptedData(&kx);
		if (ret) {
		    krb5_set_error_message(context, ret, "encoding of PKINIT-KX failed %d", ret);
		    free_PA_PK_AS_REP(&rep);
		    goto out;
		}
		if (kxlen != size)
		    krb5_abortx(context, "Internal ASN.1 encoder error");
		/* Add PA-PKINIT-KX */
		ret = krb5_padata_add(context, md, KRB5_PADATA_PKINIT_KX, kxdata, kxlen);
		if (ret) {
		    krb5_set_error_message(context, ret,
					   "Failed adding PKINIT-KX %d", ret);
		    free(buf);
		    goto out;
		}
	    }
	}

#define use_btmm_with_enckey 0
	if (use_btmm_with_enckey && rep.element == choice_PA_PK_AS_REP_encKeyPack) {
	    PA_PK_AS_REP_BTMM btmm;
	    heim_any any;

	    any.data = rep.u.encKeyPack.data;
	    any.length = rep.u.encKeyPack.length;

	    btmm.dhSignedData = NULL;
	    btmm.encKeyPack = &any;

	    ASN1_MALLOC_ENCODE(PA_PK_AS_REP_BTMM, buf, len, &btmm, &size, ret);
	} else {
	    ASN1_MALLOC_ENCODE(PA_PK_AS_REP, buf, len, &rep, &size, ret);
	}

	free_PA_PK_AS_REP(&rep);
	if (ret) {
	    krb5_set_error_message(context, ret,
				   "encode PA-PK-AS-REP failed %d", ret);
	    goto out;
	}
	if (len != size)
	    krb5_abortx(context, "Internal ASN.1 encoder error");

	kdc_log(context, config, 0, "PK-INIT using %s %s", type, other);

    } else if (cp->type == PKINIT_WIN2K) {
	PA_PK_AS_REP_Win2k rep;
	ContentInfo info;

	if (cp->keyex != USE_RSA) {
	    ret = KRB5KRB_ERR_GENERIC;
	    krb5_set_error_message(context, ret,
				   "Windows PK-INIT doesn't support DH");
	    goto out;
	}

	memset(&rep, 0, sizeof(rep));

	pa_type = KRB5_PADATA_PK_AS_REP_19;
	rep.element = choice_PA_PK_AS_REP_Win2k_encKeyPack;

	ret = krb5_generate_random_keyblock(context, enctype,
					    &cp->reply_key);
	if (ret) {
	    free_PA_PK_AS_REP_Win2k(&rep);
	    goto out;
	}
	ret = pk_mk_pa_reply_enckey(context,
				    config,
				    cp,
				    req,
				    req_buffer,
				    &cp->reply_key,
				    &info,
				    &kdc_cert);
	if (ret) {
	    free_PA_PK_AS_REP_Win2k(&rep);
	    goto out;
	}
	ASN1_MALLOC_ENCODE(ContentInfo, rep.u.encKeyPack.data,
			   rep.u.encKeyPack.length, &info, &size,
			   ret);
	free_ContentInfo(&info);
	if (ret) {
	    krb5_set_error_message(context, ret, "encoding of Key ContentInfo "
				  "failed %d", ret);
	    free_PA_PK_AS_REP_Win2k(&rep);
	    goto out;
	}
	if (rep.u.encKeyPack.length != size)
	    krb5_abortx(context, "Internal ASN.1 encoder error");

	ASN1_MALLOC_ENCODE(PA_PK_AS_REP_Win2k, buf, len, &rep, &size, ret);
	free_PA_PK_AS_REP_Win2k(&rep);
	if (ret) {
	    krb5_set_error_message(context, ret,
				  "encode PA-PK-AS-REP-Win2k failed %d", ret);
	    goto out;
	}
	if (len != size)
	    krb5_abortx(context, "Internal ASN.1 encoder error");

	ret = krb5_generate_random_keyblock(context, sessionetype,
					    sessionkey);
	if (ret) {
	    free(buf);
	    goto out;
	}

    } else
	krb5_abortx(context, "PK-INIT internal error");


    ret = krb5_padata_add(context, md, pa_type, buf, len);
    if (ret) {
	krb5_set_error_message(context, ret,
			       "Failed adding PA-PK-AS-REP %d", ret);
	free(buf);
	goto out;
    }

    if (config->pkinit_kdc_ocsp_file) {

	if (ocsp.expire == 0 && ocsp.next_update > kdc_time) {
	    struct stat sb;
	    int fd;

	    krb5_data_free(&ocsp.data);

	    ocsp.expire = 0;
	    ocsp.next_update = kdc_time + 60 * 5;

	    fd = open(config->pkinit_kdc_ocsp_file, O_RDONLY);
	    if (fd < 0) {
		kdc_log(context, config, 0,
			"PK-INIT failed to open ocsp data file %d", errno);
		goto out_ocsp;
	    }
	    ret = fstat(fd, &sb);
	    if (ret) {
		ret = errno;
		close(fd);
		kdc_log(context, config, 0,
			"PK-INIT failed to stat ocsp data %d", ret);
		goto out_ocsp;
	    }

	    ret = krb5_data_alloc(&ocsp.data, sb.st_size);
	    if (ret) {
		close(fd);
		kdc_log(context, config, 0,
			"PK-INIT failed to stat ocsp data %d", ret);
		goto out_ocsp;
	    }
	    ocsp.data.length = sb.st_size;
	    ret = read(fd, ocsp.data.data, sb.st_size);
	    close(fd);
	    if (ret != sb.st_size) {
		kdc_log(context, config, 0,
			"PK-INIT failed to read ocsp data %d", errno);
		goto out_ocsp;
	    }

	    ret = hx509_ocsp_verify(context->hx509ctx,
				    kdc_time,
				    kdc_cert,
				    0,
				    ocsp.data.data, ocsp.data.length,
				    &ocsp.expire);
	    if (ret) {
		kdc_log(context, config, 0,
			"PK-INIT failed to verify ocsp data %d", ret);
		krb5_data_free(&ocsp.data);
		ocsp.expire = 0;
	    } else if (ocsp.expire > 180) {
		ocsp.expire -= 180; /* refetch the ocsp before it expire */
		ocsp.next_update = ocsp.expire;
	    } else {
		ocsp.next_update = kdc_time;
	    }
	out_ocsp:
	    ret = 0;
	}

	if (ocsp.expire != 0 && ocsp.expire > kdc_time) {

	    ret = krb5_padata_add(context, md,
				  KRB5_PADATA_PA_PK_OCSP_RESPONSE,
				  ocsp.data.data, ocsp.data.length);
	    if (ret) {
		krb5_set_error_message(context, ret,
				       "Failed adding OCSP response %d", ret);
		goto out;
	    }
	}
    }

out:
    if (kdc_cert)
	hx509_cert_free(kdc_cert);

    if (ret == 0)
	ret = krb5_copy_keyblock_contents(context, &cp->reply_key, reply_key);
    return ret;
}
Beispiel #27
0
krb5_error_code
_kdc_as_rep(krb5_context context,
	    krb5_kdc_configuration *config,
	    KDC_REQ *req,
	    const krb5_data *req_buffer,
	    krb5_data *reply,
	    const char *from,
	    struct sockaddr *from_addr,
	    int datagram_reply)
{
    KDC_REQ_BODY *b = &req->req_body;
    AS_REP rep;
    KDCOptions f = b->kdc_options;
    hdb_entry_ex *client = NULL, *server = NULL;
    HDB *clientdb;
    krb5_enctype setype, sessionetype;
    krb5_data e_data;
    EncTicketPart et;
    EncKDCRepPart ek;
    krb5_principal client_princ = NULL, server_princ = NULL;
    char *client_name = NULL, *server_name = NULL;
    krb5_error_code ret = 0;
    const char *e_text = NULL;
    krb5_crypto crypto;
    Key *ckey, *skey;
    EncryptionKey *reply_key = NULL, session_key;
    int flags = HDB_F_FOR_AS_REQ;
#ifdef PKINIT
    pk_client_params *pkp = NULL;
#endif

    memset(&rep, 0, sizeof(rep));
    memset(&session_key, 0, sizeof(session_key));
    krb5_data_zero(&e_data);

    ALLOC(rep.padata);
    rep.padata->len = 0;
    rep.padata->val = NULL;

    if (f.canonicalize)
	flags |= HDB_F_CANON;

    if(b->sname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No server in request";
    } else{
	ret = _krb5_principalname2krb5_principal (context,
						  &server_princ,
						  *(b->sname),
						  b->realm);
	if (ret == 0)
	    ret = krb5_unparse_name(context, server_princ, &server_name);
    }
    if (ret) {
	kdc_log(context, config, 0,
		"AS-REQ malformed server name from %s", from);
	goto out;
    }
    if(b->cname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No client in request";
    } else {
	ret = _krb5_principalname2krb5_principal (context,
						  &client_princ,
						  *(b->cname),
						  b->realm);
	if (ret)
	    goto out;

	ret = krb5_unparse_name(context, client_princ, &client_name);
    }
    if (ret) {
	kdc_log(context, config, 0,
		"AS-REQ malformed client name from %s", from);
	goto out;
    }

    kdc_log(context, config, 0, "AS-REQ %s from %s for %s",
	    client_name, from, server_name);

    /*
     *
     */

    if (_kdc_is_anonymous(context, client_princ)) {
	if (!b->kdc_options.request_anonymous) {
	    kdc_log(context, config, 0, "Anonymous ticket w/o anonymous flag");
	    ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	    goto out;
	}
    } else if (b->kdc_options.request_anonymous) {
	kdc_log(context, config, 0,
		"Request for a anonymous ticket with non "
		"anonymous client name: %s", client_name);
	ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	goto out;
    }

    /*
     *
     */

    ret = _kdc_db_fetch(context, config, client_princ,
			HDB_F_GET_CLIENT | flags, NULL,
			&clientdb, &client);
    if(ret == HDB_ERR_NOT_FOUND_HERE) {
	kdc_log(context, config, 5, "client %s does not have secrets at this KDC, need to proxy", client_name);
	goto out;
    } else if(ret){
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name, msg);
	krb5_free_error_message(context, msg);
	ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	goto out;
    }
    ret = _kdc_db_fetch(context, config, server_princ,
			HDB_F_GET_SERVER|HDB_F_GET_KRBTGT | flags,
			NULL, NULL, &server);
    if(ret == HDB_ERR_NOT_FOUND_HERE) {
	kdc_log(context, config, 5, "target %s does not have secrets at this KDC, need to proxy", server_name);
	goto out;
    } else if(ret){
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name, msg);
	krb5_free_error_message(context, msg);
	ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
	goto out;
    }

    memset(&et, 0, sizeof(et));
    memset(&ek, 0, sizeof(ek));

    /*
     * Select a session enctype from the list of the crypto system
     * supported enctypes that is supported by the client and is one of
     * the enctype of the enctype of the service (likely krbtgt).
     *
     * The latter is used as a hint of what enctypes all KDC support,
     * to make sure a newer version of KDC won't generate a session
     * enctype that an older version of a KDC in the same realm can't
     * decrypt.
     */
    ret = _kdc_find_etype(context, config->as_use_strongest_session_key, FALSE,
			  client, b->etype.val, b->etype.len, &sessionetype,
			  NULL);
    if (ret) {
	kdc_log(context, config, 0,
		"Client (%s) from %s has no common enctypes with KDC "
		"to use for the session key",
		client_name, from);
	goto out;
    }
    /*
     * But if the KDC admin is paranoid and doesn't want to have "not
     * the best" enctypes on the krbtgt, lets save the best pick from
     * the client list and hope that that will work for any other
     * KDCs.
     */

    /*
     * Pre-auth processing
     */

    if(req->padata){
	int i;
	const PA_DATA *pa;
	int found_pa = 0;

	log_patypes(context, config, req->padata);

#ifdef PKINIT
	kdc_log(context, config, 5,
		"Looking for PKINIT pa-data -- %s", client_name);

	e_text = "No PKINIT PA found";

	i = 0;
	pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ);
	if (pa == NULL) {
	    i = 0;
	    pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN);
	}
	if (pa) {
	    char *client_cert = NULL;

	    ret = _kdc_pk_rd_padata(context, config, req, pa, client, &pkp);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5,
			"Failed to decode PKINIT PA-DATA -- %s",
			client_name);
		goto ts_enc;
	    }
	    if (ret == 0 && pkp == NULL)
		goto ts_enc;

	    ret = _kdc_pk_check_client(context,
				       config,
				       clientdb,
				       client,
				       pkp,
				       &client_cert);
	    if (ret) {
		e_text = "PKINIT certificate not allowed to "
		    "impersonate principal";
		_kdc_pk_free_client_param(context, pkp);

		kdc_log(context, config, 0, "%s", e_text);
		pkp = NULL;
		goto out;
	    }

	    found_pa = 1;
	    et.flags.pre_authent = 1;
	    kdc_log(context, config, 0,
		    "PKINIT pre-authentication succeeded -- %s using %s",
		    client_name, client_cert);
	    free(client_cert);
	    if (pkp)
		goto preauth_done;
	}
    ts_enc:
#endif

	if (client->entry.flags.locked_out) {
	    ret = KRB5KDC_ERR_CLIENT_REVOKED;
	    kdc_log(context, config, 0,
		    "Client (%s) is locked out", client_name);
	    goto out;
	}

	kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s",
		client_name);

	i = 0;
	e_text = "No ENC-TS found";
	while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){
	    krb5_data ts_data;
	    PA_ENC_TS_ENC p;
	    size_t len;
	    EncryptedData enc_data;
	    Key *pa_key;
	    char *str;

	    found_pa = 1;

	    if (b->kdc_options.request_anonymous) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 0, "ENC-TS doesn't support anon");
		goto out;
	    }

	    ret = decode_EncryptedData(pa->padata_value.data,
				       pa->padata_value.length,
				       &enc_data,
				       &len);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s",
			client_name);
		goto out;
	    }

	    ret = hdb_enctype2key(context, &client->entry,
				  enc_data.etype, &pa_key);
	    if(ret){
		char *estr;
		e_text = "No key matches pa-data";
		ret = KRB5KDC_ERR_ETYPE_NOSUPP;
		if(krb5_enctype_to_string(context, enc_data.etype, &estr))
		    estr = NULL;
		if(estr == NULL)
		    kdc_log(context, config, 5,
			    "No client key matching pa-data (%d) -- %s",
			    enc_data.etype, client_name);
		else
		    kdc_log(context, config, 5,
			    "No client key matching pa-data (%s) -- %s",
			    estr, client_name);
		free(estr);
		free_EncryptedData(&enc_data);

		continue;
	    }

	try_next_key:
	    ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto);
	    if (ret) {
		const char *msg = krb5_get_error_message(context, ret);
		kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
		krb5_free_error_message(context, msg);
		free_EncryptedData(&enc_data);
		continue;
	    }

	    ret = krb5_decrypt_EncryptedData (context,
					      crypto,
					      KRB5_KU_PA_ENC_TIMESTAMP,
					      &enc_data,
					      &ts_data);
	    krb5_crypto_destroy(context, crypto);
	    /*
	     * Since the user might have several keys with the same
	     * enctype but with diffrent salting, we need to try all
	     * the keys with the same enctype.
	     */
	    if(ret){
		krb5_error_code ret2;
		const char *msg = krb5_get_error_message(context, ret);

		ret2 = krb5_enctype_to_string(context,
					      pa_key->key.keytype, &str);
		if (ret2)
		    str = NULL;
		kdc_log(context, config, 5,
			"Failed to decrypt PA-DATA -- %s "
			"(enctype %s) error %s",
			client_name, str ? str : "unknown enctype", msg);
		krb5_free_error_message(context, msg);
		free(str);

		if(hdb_next_enctype2key(context, &client->entry,
					enc_data.etype, &pa_key) == 0)
		    goto try_next_key;
		e_text = "Failed to decrypt PA-DATA";

		free_EncryptedData(&enc_data);

		if (clientdb->hdb_auth_status)
		    (clientdb->hdb_auth_status)(context, clientdb, client, HDB_AUTH_WRONG_PASSWORD);

		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		continue;
	    }
	    free_EncryptedData(&enc_data);
	    ret = decode_PA_ENC_TS_ENC(ts_data.data,
				       ts_data.length,
				       &p,
				       &len);
	    krb5_data_free(&ts_data);
	    if(ret){
		e_text = "Failed to decode PA-ENC-TS-ENC";
		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		kdc_log(context, config,
			5, "Failed to decode PA-ENC-TS_ENC -- %s",
			client_name);
		continue;
	    }
	    free_PA_ENC_TS_ENC(&p);
	    if (abs(kdc_time - p.patimestamp) > context->max_skew) {
		char client_time[100];

		krb5_format_time(context, p.patimestamp,
				 client_time, sizeof(client_time), TRUE);

 		ret = KRB5KRB_AP_ERR_SKEW;
 		kdc_log(context, config, 0,
			"Too large time skew, "
			"client time %s is out by %u > %u seconds -- %s",
			client_time,
			(unsigned)abs(kdc_time - p.patimestamp),
			context->max_skew,
			client_name);

		/*
		 * The following is needed to make windows clients to
		 * retry using the timestamp in the error message, if
		 * there is a e_text, they become unhappy.
		 */
		e_text = NULL;
		goto out;
	    }
	    et.flags.pre_authent = 1;

	    set_salt_padata(rep.padata, pa_key->salt);

	    reply_key = &pa_key->key;

	    ret = krb5_enctype_to_string(context, pa_key->key.keytype, &str);
	    if (ret)
		str = NULL;

	    kdc_log(context, config, 2,
		    "ENC-TS Pre-authentication succeeded -- %s using %s",
		    client_name, str ? str : "unknown enctype");
	    free(str);
	    break;
	}
#ifdef PKINIT
    preauth_done:
#endif
	if(found_pa == 0 && config->require_preauth)
	    goto use_pa;
	/* We come here if we found a pa-enc-timestamp, but if there
           was some problem with it, other than too large skew */
	if(found_pa && et.flags.pre_authent == 0){
	    kdc_log(context, config, 0, "%s -- %s", e_text, client_name);
	    e_text = NULL;
	    goto out;
	}
    }else if (config->require_preauth
	      || b->kdc_options.request_anonymous /* hack to force anon */
	      || client->entry.flags.require_preauth
	      || server->entry.flags.require_preauth) {
	METHOD_DATA method_data;
	PA_DATA *pa;
	unsigned char *buf;
	size_t len;

    use_pa:
	method_data.len = 0;
	method_data.val = NULL;

	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_ENC_TIMESTAMP;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

#ifdef PKINIT
	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ_WIN;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;
#endif

	/*
	 * If there is a client key, send ETYPE_INFO{,2}
	 */
	ret = _kdc_find_etype(context,
			      config->preauth_use_strongest_session_key, TRUE,
			      client, b->etype.val, b->etype.len, NULL, &ckey);
	if (ret == 0) {

	    /*
	     * RFC4120 requires:
	     * - If the client only knows about old enctypes, then send
	     *   both info replies (we send 'info' first in the list).
	     * - If the client is 'modern', because it knows about 'new'
	     *   enctype types, then only send the 'info2' reply.
	     *
	     * Before we send the full list of etype-info data, we pick
	     * the client key we would have used anyway below, just pick
	     * that instead.
	     */

	    if (older_enctype(ckey->key.keytype)) {
		ret = get_pa_etype_info(context, config,
					&method_data, ckey);
		if (ret) {
		    free_METHOD_DATA(&method_data);
		    goto out;
		}
	    }
	    ret = get_pa_etype_info2(context, config,
				     &method_data, ckey);
	    if (ret) {
		free_METHOD_DATA(&method_data);
		goto out;
	    }
	}

	ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret);
	free_METHOD_DATA(&method_data);

	e_data.data   = buf;
	e_data.length = len;
	e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ",

	ret = KRB5KDC_ERR_PREAUTH_REQUIRED;

	kdc_log(context, config, 0,
		"No preauth found, returning PREAUTH-REQUIRED -- %s",
		client_name);
	goto out;
    }

    /*
     * Verify flags after the user been required to prove its identity
     * with in a preauth mech.
     */

    ret = _kdc_check_access(context, config, client, client_name,
			    server, server_name,
			    req, &e_data);
    if(ret)
	goto out;

    if (clientdb->hdb_auth_status)
	(clientdb->hdb_auth_status)(context, clientdb, client,
				    HDB_AUTH_SUCCESS);

    /*
     * Selelct the best encryption type for the KDC with out regard to
     * the client since the client never needs to read that data.
     */

    ret = _kdc_get_preferred_key(context, config,
				 server, server_name,
				 &setype, &skey);
    if(ret)
	goto out;

    if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey
       || (f.request_anonymous && !config->allow_anonymous)) {
	ret = KRB5KDC_ERR_BADOPTION;
	e_text = "Bad KDC options";
	kdc_log(context, config, 0, "Bad KDC options -- %s", client_name);
	goto out;
    }

    rep.pvno = 5;
    rep.msg_type = krb_as_rep;

    ret = copy_Realm(&client->entry.principal->realm, &rep.crealm);
    if (ret)
	goto out;
    ret = _krb5_principal2principalname(&rep.cname, client->entry.principal);
    if (ret)
	goto out;

    rep.ticket.tkt_vno = 5;
    copy_Realm(&server->entry.principal->realm, &rep.ticket.realm);
    _krb5_principal2principalname(&rep.ticket.sname,
				  server->entry.principal);
    /* java 1.6 expects the name to be the same type, lets allow that
     * uncomplicated name-types. */
#define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
    if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
	rep.ticket.sname.name_type = b->sname->name_type;
#undef CNT

    et.flags.initial = 1;
    if(client->entry.flags.forwardable && server->entry.flags.forwardable)
	et.flags.forwardable = f.forwardable;
    else if (f.forwardable) {
	e_text = "Ticket may not be forwardable";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be forwardable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.proxiable && server->entry.flags.proxiable)
	et.flags.proxiable = f.proxiable;
    else if (f.proxiable) {
	e_text = "Ticket may not be proxiable";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be proxiable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.postdate && server->entry.flags.postdate)
	et.flags.may_postdate = f.allow_postdate;
    else if (f.allow_postdate){
	e_text = "Ticket may not be postdate";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be postdatable -- %s", client_name);
	goto out;
    }

    /* check for valid set of addresses */
    if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
	e_text = "Bad address list in requested";
	ret = KRB5KRB_AP_ERR_BADADDR;
	kdc_log(context, config, 0,
		"Bad address list requested -- %s", client_name);
	goto out;
    }

    ret = copy_PrincipalName(&rep.cname, &et.cname);
    if (ret)
	goto out;
    ret = copy_Realm(&rep.crealm, &et.crealm);
    if (ret)
	goto out;

    {
	time_t start;
	time_t t;

	start = et.authtime = kdc_time;

	if(f.postdated && req->req_body.from){
	    ALLOC(et.starttime);
	    start = *et.starttime = *req->req_body.from;
	    et.flags.invalid = 1;
	    et.flags.postdated = 1; /* XXX ??? */
	}
	_kdc_fix_time(&b->till);
	t = *b->till;

	/* be careful not overflowing */

	if(client->entry.max_life)
	    t = start + min(t - start, *client->entry.max_life);
	if(server->entry.max_life)
	    t = start + min(t - start, *server->entry.max_life);
#if 0
	t = min(t, start + realm->max_life);
#endif
	et.endtime = t;
	if(f.renewable_ok && et.endtime < *b->till){
	    f.renewable = 1;
	    if(b->rtime == NULL){
		ALLOC(b->rtime);
		*b->rtime = 0;
	    }
	    if(*b->rtime < *b->till)
		*b->rtime = *b->till;
	}
	if(f.renewable && b->rtime){
	    t = *b->rtime;
	    if(t == 0)
		t = MAX_TIME;
	    if(client->entry.max_renew)
		t = start + min(t - start, *client->entry.max_renew);
	    if(server->entry.max_renew)
		t = start + min(t - start, *server->entry.max_renew);
#if 0
	    t = min(t, start + realm->max_renew);
#endif
	    ALLOC(et.renew_till);
	    *et.renew_till = t;
	    et.flags.renewable = 1;
	}
    }

    if (f.request_anonymous)
	et.flags.anonymous = 1;

    if(b->addresses){
	ALLOC(et.caddr);
	copy_HostAddresses(b->addresses, et.caddr);
    }

    et.transited.tr_type = DOMAIN_X500_COMPRESS;
    krb5_data_zero(&et.transited.contents);

    /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
     * as 0 and as 0x80 (meaning indefinite length) apart, and is thus
     * incapable of correctly decoding SEQUENCE OF's of zero length.
     *
     * To fix this, always send at least one no-op last_req
     *
     * If there's a pw_end or valid_end we will use that,
     * otherwise just a dummy lr.
     */
    ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val));
    if (ek.last_req.val == NULL) {
	ret = ENOMEM;
	goto out;
    }
    ek.last_req.len = 0;
    if (client->entry.pw_end
	&& (config->kdc_warn_pwexpire == 0
	    || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_PW_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end;
	++ek.last_req.len;
    }
    if (client->entry.valid_end) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_ACCT_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end;
	++ek.last_req.len;
    }
    if (ek.last_req.len == 0) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_NONE;
	ek.last_req.val[ek.last_req.len].lr_value = 0;
	++ek.last_req.len;
    }
    ek.nonce = b->nonce;
    if (client->entry.valid_end || client->entry.pw_end) {
	ALLOC(ek.key_expiration);
	if (client->entry.valid_end) {
	    if (client->entry.pw_end)
		*ek.key_expiration = min(*client->entry.valid_end,
					 *client->entry.pw_end);
	    else
		*ek.key_expiration = *client->entry.valid_end;
	} else
	    *ek.key_expiration = *client->entry.pw_end;
    } else
	ek.key_expiration = NULL;
    ek.flags = et.flags;
    ek.authtime = et.authtime;
    if (et.starttime) {
	ALLOC(ek.starttime);
	*ek.starttime = *et.starttime;
    }
    ek.endtime = et.endtime;
    if (et.renew_till) {
	ALLOC(ek.renew_till);
	*ek.renew_till = *et.renew_till;
    }
    copy_Realm(&rep.ticket.realm, &ek.srealm);
    copy_PrincipalName(&rep.ticket.sname, &ek.sname);
    if(et.caddr){
	ALLOC(ek.caddr);
	copy_HostAddresses(et.caddr, ek.caddr);
    }

#if PKINIT
    if (pkp) {
        e_text = "Failed to build PK-INIT reply";
	ret = _kdc_pk_mk_pa_reply(context, config, pkp, client,
				  sessionetype, req, req_buffer,
				  &reply_key, &et.key, rep.padata);
	if (ret)
	    goto out;
	ret = _kdc_add_inital_verified_cas(context,
					   config,
					   pkp,
					   &et);
	if (ret)
	    goto out;

    } else
#endif
    {
	ret = krb5_generate_random_keyblock(context, sessionetype, &et.key);
	if (ret)
	    goto out;
    }

    if (reply_key == NULL) {
	e_text = "Client have no reply key";
	ret = KRB5KDC_ERR_CLIENT_NOTYET;
	goto out;
    }

    ret = copy_EncryptionKey(&et.key, &ek.key);
    if (ret)
	goto out;

    if (rep.padata->len == 0) {
	free(rep.padata);
	rep.padata = NULL;
    }

    /* Add the PAC */
    if (send_pac_p(context, req)) {
	krb5_pac p = NULL;
	krb5_data data;

	ret = _kdc_pac_generate(context, client, &p);
	if (ret) {
	    kdc_log(context, config, 0, "PAC generation failed for -- %s",
		    client_name);
	    goto out;
	}
	if (p != NULL) {
	    ret = _krb5_pac_sign(context, p, et.authtime,
				 client->entry.principal,
				 &skey->key, /* Server key */
				 &skey->key, /* FIXME: should be krbtgt key */
				 &data);
	    krb5_pac_free(context, p);
	    if (ret) {
		kdc_log(context, config, 0, "PAC signing failed for -- %s",
			client_name);
		goto out;
	    }

	    ret = _kdc_tkt_add_if_relevant_ad(context, &et,
					      KRB5_AUTHDATA_WIN2K_PAC,
					      &data);
	    krb5_data_free(&data);
	    if (ret)
		goto out;
	}
    }

    _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime,
		       et.endtime, et.renew_till);

    /* do this as the last thing since this signs the EncTicketPart */
    ret = _kdc_add_KRB5SignedPath(context,
				  config,
				  server,
				  setype,
				  client->entry.principal,
				  NULL,
				  NULL,
				  &et);
    if (ret)
	goto out;

    log_as_req(context, config, reply_key->keytype, setype, b);

    ret = _kdc_encode_reply(context, config,
			    &rep, &et, &ek, setype, server->entry.kvno,
			    &skey->key, client->entry.kvno,
			    reply_key, 0, &e_text, reply);
    free_EncTicketPart(&et);
    free_EncKDCRepPart(&ek);
    if (ret)
	goto out;

    /* */
    if (datagram_reply && reply->length > config->max_datagram_reply_length) {
	krb5_data_free(reply);
	ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
	e_text = "Reply packet too large";
    }

out:
    free_AS_REP(&rep);
    if(ret != 0 && ret != HDB_ERR_NOT_FOUND_HERE){
	krb5_mk_error(context,
		      ret,
		      e_text,
		      (e_data.data ? &e_data : NULL),
		      client_princ,
		      server_princ,
		      NULL,
		      NULL,
		      reply);
	ret = 0;
    }
#ifdef PKINIT
    if (pkp)
	_kdc_pk_free_client_param(context, pkp);
#endif
    if (e_data.data)
        free(e_data.data);
    if (client_princ)
	krb5_free_principal(context, client_princ);
    free(client_name);
    if (server_princ)
	krb5_free_principal(context, server_princ);
    free(server_name);
    if(client)
	_kdc_free_ent(context, client);
    if(server)
	_kdc_free_ent(context, server);
    return ret;
}
Beispiel #28
0
static krb5_error_code
pk_mk_pa_reply_enckey(krb5_context context,
		      krb5_kdc_configuration *config,
		      pk_client_params *cp,
		      const KDC_REQ *req,
		      const krb5_data *req_buffer,
		      krb5_keyblock *reply_key,
		      ContentInfo *content_info,
		      hx509_cert *kdc_cert)
{
    const heim_oid *envelopedAlg = NULL, *sdAlg = NULL, *evAlg = NULL;
    krb5_error_code ret;
    krb5_data buf, signed_data;
    size_t size = 0;
    int do_win2k = 0;

    krb5_data_zero(&buf);
    krb5_data_zero(&signed_data);

    *kdc_cert = NULL;

    /*
     * If the message client is a win2k-type but it send pa data
     * 09-binding it expects a IETF (checksum) reply so there can be
     * no replay attacks.
     */

    switch (cp->type) {
    case PKINIT_WIN2K: {
	int i = 0;
	if (_kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_09_BINDING) == NULL
	    && config->pkinit_require_binding == 0)
	{
	    do_win2k = 1;
	}
	sdAlg = &asn1_oid_id_pkcs7_data;
	evAlg = &asn1_oid_id_pkcs7_data;
	envelopedAlg = &asn1_oid_id_rsadsi_des_ede3_cbc;
	break;
    }
    case PKINIT_27:
	sdAlg = &asn1_oid_id_pkrkeydata;
	evAlg = &asn1_oid_id_pkcs7_signedData;
	break;
    default:
	krb5_abortx(context, "internal pkinit error");
    }

    if (do_win2k) {
	ReplyKeyPack_Win2k kp;
	memset(&kp, 0, sizeof(kp));

	ret = copy_EncryptionKey(reply_key, &kp.replyKey);
	if (ret) {
	    krb5_clear_error_message(context);
	    goto out;
	}
	kp.nonce = cp->nonce;

	ASN1_MALLOC_ENCODE(ReplyKeyPack_Win2k,
			   buf.data, buf.length,
			   &kp, &size,ret);
	free_ReplyKeyPack_Win2k(&kp);
    } else {
	krb5_crypto ascrypto;
	ReplyKeyPack kp;
	memset(&kp, 0, sizeof(kp));

	ret = copy_EncryptionKey(reply_key, &kp.replyKey);
	if (ret) {
	    krb5_clear_error_message(context);
	    goto out;
	}

	ret = krb5_crypto_init(context, reply_key, 0, &ascrypto);
	if (ret) {
	    krb5_clear_error_message(context);
	    goto out;
	}

	ret = krb5_create_checksum(context, ascrypto, 6, 0,
				   req_buffer->data, req_buffer->length,
				   &kp.asChecksum);
	if (ret) {
	    krb5_clear_error_message(context);
	    goto out;
	}

	ret = krb5_crypto_destroy(context, ascrypto);
	if (ret) {
	    krb5_clear_error_message(context);
	    goto out;
	}
	ASN1_MALLOC_ENCODE(ReplyKeyPack, buf.data, buf.length, &kp, &size,ret);
	free_ReplyKeyPack(&kp);
    }
    if (ret) {
	krb5_set_error_message(context, ret, "ASN.1 encoding of ReplyKeyPack "
			       "failed (%d)", ret);
	goto out;
    }
    if (buf.length != size)
	krb5_abortx(context, "Internal ASN.1 encoder error");

    {
	hx509_query *q;
	hx509_cert cert;

	ret = hx509_query_alloc(context->hx509ctx, &q);
	if (ret)
	    goto out;

	hx509_query_match_option(q, HX509_QUERY_OPTION_PRIVATE_KEY);
	if (config->pkinit_kdc_friendly_name)
	    hx509_query_match_friendly_name(q, config->pkinit_kdc_friendly_name);

	ret = hx509_certs_find(context->hx509ctx,
			       kdc_identity->certs,
			       q,
			       &cert);
	hx509_query_free(context->hx509ctx, q);
	if (ret)
	    goto out;

	ret = hx509_cms_create_signed_1(context->hx509ctx,
					0,
					sdAlg,
					buf.data,
					buf.length,
					NULL,
					cert,
					cp->peer,
					cp->client_anchors,
					kdc_identity->certpool,
					&signed_data);
	*kdc_cert = cert;
    }

    krb5_data_free(&buf);
    if (ret)
	goto out;

    if (cp->type == PKINIT_WIN2K) {
	ret = hx509_cms_wrap_ContentInfo(&asn1_oid_id_pkcs7_signedData,
					 &signed_data,
					 &buf);
	if (ret)
	    goto out;
	krb5_data_free(&signed_data);
	signed_data = buf;
    }

    ret = hx509_cms_envelope_1(context->hx509ctx,
			       HX509_CMS_EV_NO_KU_CHECK,
			       cp->cert,
			       signed_data.data, signed_data.length,
			       envelopedAlg,
			       evAlg, &buf);
    if (ret)
	goto out;

    ret = _krb5_pk_mk_ContentInfo(context,
				  &buf,
				  &asn1_oid_id_pkcs7_envelopedData,
				  content_info);
out:
    if (ret && *kdc_cert) {
        hx509_cert_free(*kdc_cert);
	*kdc_cert = NULL;
    }

    krb5_data_free(&buf);
    krb5_data_free(&signed_data);
    return ret;
}
Beispiel #29
0
static krb5_error_code
get_cred_kdc(krb5_context context,
	     krb5_ccache id,
	     krb5_kdc_flags flags,
	     krb5_addresses *addresses,
	     krb5_creds *in_creds,
	     krb5_creds *krbtgt,
	     krb5_principal impersonate_principal,
	     Ticket *second_ticket,
	     krb5_creds *out_creds)
{
    TGS_REQ req;
    krb5_data enc;
    krb5_data resp;
    krb5_kdc_rep rep;
    KRB_ERROR error;
    krb5_error_code ret;
    unsigned nonce;
    krb5_keyblock *subkey = NULL;
    size_t len;
    Ticket second_ticket_data;
    METHOD_DATA padata;

    krb5_data_zero(&resp);
    krb5_data_zero(&enc);
    padata.val = NULL;
    padata.len = 0;

    krb5_generate_random_block(&nonce, sizeof(nonce));
    nonce &= 0xffffffff;

    if(flags.b.enc_tkt_in_skey && second_ticket == NULL){
	ret = decode_Ticket(in_creds->second_ticket.data,
			    in_creds->second_ticket.length,
			    &second_ticket_data, &len);
	if(ret)
	    return ret;
	second_ticket = &second_ticket_data;
    }


    if (impersonate_principal) {
	krb5_crypto crypto;
	PA_S4U2Self self;
	krb5_data data;
	void *buf;
	size_t size;

	self.name = impersonate_principal->name;
	self.realm = impersonate_principal->realm;
	self.auth = estrdup("Kerberos");
	
	ret = _krb5_s4u2self_to_checksumdata(context, &self, &data);
	if (ret) {
	    free(self.auth);
	    goto out;
	}

	ret = krb5_crypto_init(context, &krbtgt->session, 0, &crypto);
	if (ret) {
	    free(self.auth);
	    krb5_data_free(&data);
	    goto out;
	}

	ret = krb5_create_checksum(context,
				   crypto,
				   KRB5_KU_OTHER_CKSUM,
				   0,
				   data.data,
				   data.length,
				   &self.cksum);
	krb5_crypto_destroy(context, crypto);
	krb5_data_free(&data);
	if (ret) {
	    free(self.auth);
	    goto out;
	}

	ASN1_MALLOC_ENCODE(PA_S4U2Self, buf, len, &self, &size, ret);
	free(self.auth);
	free_Checksum(&self.cksum);
	if (ret)
	    goto out;
	if (len != size)
	    krb5_abortx(context, "internal asn1 error");
	
	ret = krb5_padata_add(context, &padata, KRB5_PADATA_FOR_USER, buf, len);
	if (ret)
	    goto out;
    }

    ret = init_tgs_req (context,
			id,
			addresses,
			flags,
			second_ticket,
			in_creds,
			krbtgt,
			nonce,
			&padata,
			&subkey,
			&req);
    if (ret)
	goto out;

    ASN1_MALLOC_ENCODE(TGS_REQ, enc.data, enc.length, &req, &len, ret);
    if (ret)
	goto out;
    if(enc.length != len)
	krb5_abortx(context, "internal error in ASN.1 encoder");

    /* don't free addresses */
    req.req_body.addresses = NULL;
    free_TGS_REQ(&req);

    /*
     * Send and receive
     */
    {
	krb5_sendto_ctx stctx;
	ret = krb5_sendto_ctx_alloc(context, &stctx);
	if (ret)
	    return ret;
	krb5_sendto_ctx_set_func(stctx, _krb5_kdc_retry, NULL);

	ret = krb5_sendto_context (context, stctx, &enc,
				   krbtgt->server->name.name_string.val[1],
				   &resp);
	krb5_sendto_ctx_free(context, stctx);
    }
    if(ret)
	goto out;

    memset(&rep, 0, sizeof(rep));
    if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0) {
	unsigned eflags = 0;

	ret = krb5_copy_principal(context,
				  in_creds->client,
				  &out_creds->client);
	if(ret)
	    goto out2;
	ret = krb5_copy_principal(context,
				  in_creds->server,
				  &out_creds->server);
	if(ret)
	    goto out2;
	/* this should go someplace else */
	out_creds->times.endtime = in_creds->times.endtime;

	/* XXX should do better testing */
	if (flags.b.constrained_delegation || impersonate_principal)
	    eflags |= EXTRACT_TICKET_ALLOW_CNAME_MISMATCH;

	ret = _krb5_extract_ticket(context,
				   &rep,
				   out_creds,
				   &krbtgt->session,
				   NULL,
				   0,
				   &krbtgt->addresses,
				   nonce,
				   eflags,
				   decrypt_tkt_with_subkey,
				   subkey);
    out2:
	krb5_free_kdc_rep(context, &rep);
    } else if(krb5_rd_error(context, &resp, &error) == 0) {
	ret = krb5_error_from_rd_error(context, &error, in_creds);
	krb5_free_error_contents(context, &error);
    } else if(resp.length > 0 && ((char*)resp.data)[0] == 4) {
	ret = KRB5KRB_AP_ERR_V4_REPLY;
	krb5_clear_error_message(context);
    } else {
	ret = KRB5KRB_AP_ERR_MSG_TYPE;
	krb5_clear_error_message(context);
    }

out:
    if (second_ticket == &second_ticket_data)
	free_Ticket(&second_ticket_data);
    free_METHOD_DATA(&padata);
    krb5_data_free(&resp);
    krb5_data_free(&enc);
    if(subkey)
	krb5_free_keyblock(context, subkey);
    return ret;

}
Beispiel #30
0
static krb5_error_code
verify_checksum(krb5_context context,
		const struct PAC_INFO_BUFFER *sig,
		const krb5_data *data,
		void *ptr, size_t len,
		const krb5_keyblock *key)
{
    krb5_storage *sp = NULL;
    uint32_t type;
    krb5_error_code ret;
    Checksum cksum;

    memset(&cksum, 0, sizeof(cksum));

    sp = krb5_storage_from_mem((char *)data->data + sig->offset_lo,
			       sig->buffersize);
    if (sp == NULL)
	return krb5_enomem(context);

    krb5_storage_set_flags(sp, KRB5_STORAGE_BYTEORDER_LE);

    CHECK(ret, krb5_ret_uint32(sp, &type), out);
    cksum.cksumtype = type;
    cksum.checksum.length =
	sig->buffersize - krb5_storage_seek(sp, 0, SEEK_CUR);
    cksum.checksum.data = malloc(cksum.checksum.length);
    if (cksum.checksum.data == NULL) {
	ret = krb5_enomem(context);
	goto out;
    }
    ret = krb5_storage_read(sp, cksum.checksum.data, cksum.checksum.length);
    if (ret != cksum.checksum.length) {
	ret = EINVAL;
	krb5_set_error_message(context, ret, "PAC checksum missing checksum");
	goto out;
    }

    if (!krb5_checksum_is_keyed(context, cksum.cksumtype)) {
	ret = EINVAL;
	krb5_set_error_message(context, ret, "Checksum type %d not keyed",
			       cksum.cksumtype);
	goto out;
    }

    /* If the checksum is HMAC-MD5, the checksum type is not tied to
     * the key type, instead the HMAC-MD5 checksum is applied blindly
     * on whatever key is used for this connection, avoiding issues
     * with unkeyed checksums on des-cbc-md5 and des-cbc-crc.  See
     * http://comments.gmane.org/gmane.comp.encryption.kerberos.devel/8743
     * for the same issue in MIT, and
     * http://blogs.msdn.com/b/openspecification/archive/2010/01/01/verifying-the-server-signature-in-kerberos-privilege-account-certificate.aspx
     * for Microsoft's explaination */

    if (cksum.cksumtype == CKSUMTYPE_HMAC_MD5) {
	Checksum local_checksum;

	memset(&local_checksum, 0, sizeof(local_checksum));

	ret = HMAC_MD5_any_checksum(context, key, ptr, len,
				    KRB5_KU_OTHER_CKSUM, &local_checksum);

	if (ret != 0 || krb5_data_ct_cmp(&local_checksum.checksum, &cksum.checksum) != 0) {
	    ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
	    krb5_set_error_message(context, ret,
				   N_("PAC integrity check failed for "
				      "hmac-md5 checksum", ""));
	}
	krb5_data_free(&local_checksum.checksum);

   } else {
	krb5_crypto crypto = NULL;

	ret = krb5_crypto_init(context, key, 0, &crypto);
	if (ret)
		goto out;

	ret = krb5_verify_checksum(context, crypto, KRB5_KU_OTHER_CKSUM,
				   ptr, len, &cksum);
	krb5_crypto_destroy(context, crypto);
    }
    free(cksum.checksum.data);
    krb5_storage_free(sp);

    return ret;

out:
    if (cksum.checksum.data)
	free(cksum.checksum.data);
    if (sp)
	krb5_storage_free(sp);
    return ret;
}