Beispiel #1
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 #2
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;
}