From patchwork Wed Aug 10 09:43:36 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: nevola X-Patchwork-Id: 657799 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3s8g1w4HZpz9rxl for ; Thu, 11 Aug 2016 04:40:20 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b=jkM1xdDy; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935723AbcHJSkO (ORCPT ); Wed, 10 Aug 2016 14:40:14 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:36760 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932501AbcHJSkN (ORCPT ); Wed, 10 Aug 2016 14:40:13 -0400 Received: by mail-wm0-f68.google.com with SMTP id i138so11222297wmf.3 for ; Wed, 10 Aug 2016 11:40:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:subject:message-id:mime-version:content-disposition :user-agent; bh=uAnYEWEsLdrnJRf6lA72fSPjTHaKlvxt5xJT9mSo67M=; b=jkM1xdDydmRg1kmZ/4riZbx32A++XcbQWdrKhDyRZtxK3xYmv+LJIqaWxX3YmIVXYU rjfgIhGfq+v6Bblt0LgYII//mRm/QnB0uGaw6Zp4NB4+YDMGvZfYMnGv9/ItNYKhiuJ2 LIKNGO7qfG1YtshC4cFZ/Iyh2SUUCuXf+SGti1pD29pA0awI3lk8UZ9eWB3oosUbp7gb Cw91gtV1zOi7y4frDdiKqnsRGn+dD7ajfOSLnwO9E71hCa3urgvrXgE5s3WOXroIL29f ZO3Jy1qU+QE0PtXmjRK+Pdzz92aDjqB3BvIfAGeO09YimbDQO+OBNbdbhXaXEKZQus/+ LBiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:subject:message-id:mime-version :content-disposition:user-agent; bh=uAnYEWEsLdrnJRf6lA72fSPjTHaKlvxt5xJT9mSo67M=; b=D9pIPmEGX23q/46c7XIJYhJjQdNFrVxYVMBTkfre38FMIJWwFuoauSL0VmRkbmzj6D ztiWv91EYf3R8T9wUqVXFFXrBqm4qho3AlEqlq2ozom5bZ86sl5dRJx32JMTJ7dwLCLO ZyTWw7F4vK2LvVB2bvs8y8Aboj857J2Gbp0WV6J3QuTPAnYuA5DB0zu/zxp/OsA8Li1+ DinZmWf25lY7xZgTgKBsUFEA45DiCZk5IAzM2uCvjmuI5H1pT2ntpBNpWIzd6vmMj4V8 e3jnV9sQyxK6cjZNT/xOwGPW8ROCsF8id8o2uzMV77PXLRt7G93SgkHg0F5IUpPygwA1 veFA== X-Gm-Message-State: AEkooutXXWZCvexeFFhgjmrS0TWqa3dF26ughN2ezpRfsxiCtU7nZEQ9lYWJ302SFfArZA== X-Received: by 10.194.28.5 with SMTP id x5mr2964241wjg.11.1470822218991; Wed, 10 Aug 2016 02:43:38 -0700 (PDT) Received: from sonyv ([91.126.73.162]) by smtp.gmail.com with ESMTPSA id qe2sm42145114wjc.28.2016.08.10.02.43.38 for (version=TLS1_2 cipher=AES128-SHA bits=128/128); Wed, 10 Aug 2016 02:43:38 -0700 (PDT) Date: Wed, 10 Aug 2016 11:43:36 +0200 From: Laura Garcia Liebana To: netfilter-devel@vger.kernel.org Subject: [PATCH v3] netfilter: nf_tables: add hash expression Message-ID: <20160810094333.GA28920@sonyv> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org This patch adds a new hash expression, this provides jhash support but this can be extended to support for other hash functions. The modulus and seed already comes embedded into this new expression. Use case example: meta mark set hash ip saddr mod 10 Signed-off-by: Laura Garcia Liebana --- Changes in V3: - Add null checks in init() - Include registers load validation include/uapi/linux/netfilter/nf_tables.h | 20 +++++ net/netfilter/Kconfig | 6 ++ net/netfilter/Makefile | 1 + net/netfilter/nft_hash.c | 141 +++++++++++++++++++++++++++++++ 4 files changed, 168 insertions(+) create mode 100644 net/netfilter/nft_hash.c diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 0e7928e..1399946 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -724,6 +724,26 @@ enum nft_meta_keys { }; /** + * enum nft_hash_attributes - nf_tables hash expression netlink attributes + * + * @NFTA_HASH_SREG: source register (NLA_U32) + * @NFTA_HASH_DREG: destination register (NLA_U32) + * @NFTA_HASH_LEN: source data length (NLA_U32) + * @NFTA_HASH_MODULUS: modulus value (NLA_U32) + * @NFTA_HASH_SEED: seed value (NLA_U32) + */ +enum nft_hash_attributes { + NFTA_HASH_UNSPEC, + NFTA_HASH_SREG, + NFTA_HASH_DREG, + NFTA_HASH_LEN, + NFTA_HASH_MODULUS, + NFTA_HASH_SEED, + __NFTA_HASH_MAX, +}; +#define NFTA_HASH_MAX (__NFTA_HASH_MAX - 1) + +/** * enum nft_meta_attributes - nf_tables meta expression netlink attributes * * @NFTA_META_DREG: destination register (NLA_U32) diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index a2e4cf6..1074700 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -569,6 +569,12 @@ config NFT_COMPAT x_tables match/target extensions over the nf_tables framework. +config NFT_HASH + tristate "Netfilter nf_tables hash module" + help + This option adds the "hash" expression that you can use to perform + a hash operation on registers. + if NF_TABLES_NETDEV config NF_DUP_NETDEV diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 441a3c0..faa277e 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -93,6 +93,7 @@ obj-$(CONFIG_NFT_COUNTER) += nft_counter.o obj-$(CONFIG_NFT_LOG) += nft_log.o obj-$(CONFIG_NFT_MASQ) += nft_masq.o obj-$(CONFIG_NFT_REDIR) += nft_redir.o +obj-$(CONFIG_NFT_HASH) += nft_hash.o # nf_tables netdev obj-$(CONFIG_NFT_DUP_NETDEV) += nft_dup_netdev.o diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c new file mode 100644 index 0000000..d0069eb --- /dev/null +++ b/net/netfilter/nft_hash.c @@ -0,0 +1,141 @@ +/* + * Copyright (c) 2016 Laura Garcia + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct nft_hash { + enum nft_registers sreg:8; + enum nft_registers dreg:8; + u8 len; + u32 modulus; + u32 seed; +}; + +static void nft_hash_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nft_hash *priv = nft_expr_priv(expr); + const void *data = ®s->data[priv->sreg]; + u32 h; + + h = reciprocal_scale(jhash(data, priv->len, priv->seed), priv->modulus); + + regs->data[priv->dreg] = h; +} + +const struct nla_policy nft_hash_policy[NFTA_HASH_MAX + 1] = { + [NFTA_HASH_SREG] = { .type = NLA_U32 }, + [NFTA_HASH_DREG] = { .type = NLA_U32 }, + [NFTA_HASH_LEN] = { .type = NLA_U32 }, + [NFTA_HASH_MODULUS] = { .type = NLA_U32 }, + [NFTA_HASH_SEED] = { .type = NLA_U32 }, +}; + +static int nft_hash_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_hash *priv = nft_expr_priv(expr); + u32 len; + u32 seed = 0; + + if (!tb[NFTA_HASH_SREG] || + !tb[NFTA_HASH_DREG] || + !tb[NFTA_HASH_LEN] || + !tb[NFTA_HASH_MODULUS]) + return -EINVAL; + + priv->sreg = nft_parse_register(tb[NFTA_HASH_SREG]); + priv->dreg = nft_parse_register(tb[NFTA_HASH_DREG]); + + len = ntohl(nla_get_be32(tb[NFTA_HASH_LEN])); + if (len == 0 || len > U8_MAX) + return -EINVAL; + + priv->len = len; + + priv->modulus = ntohl(nla_get_be32(tb[NFTA_HASH_MODULUS])); + if (priv->modulus <= 1) + return -EINVAL; + + if (tb[NFTA_HASH_LEN]) + seed = ntohl(nla_get_be32(tb[NFTA_HASH_SEED])); + + priv->seed = seed; + + return nft_validate_register_store(ctx, priv->sreg, NULL, + NFT_DATA_VALUE, len) && + nft_validate_register_store(ctx, priv->dreg, NULL, + NFT_DATA_VALUE, sizeof(u32)); +} + +static int nft_hash_dump(struct sk_buff *skb, + const struct nft_expr *expr) +{ + const struct nft_hash *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_HASH_SREG, priv->sreg)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_HASH_DREG, priv->dreg)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_HASH_LEN, priv->len)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_HASH_MODULUS, priv->modulus)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_HASH_SEED, priv->seed)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_hash_type; +static const struct nft_expr_ops nft_hash_ops = { + .type = &nft_hash_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_hash)), + .eval = nft_hash_eval, + .init = nft_hash_init, + .dump = nft_hash_dump, +}; + +static struct nft_expr_type nft_hash_type __read_mostly = { + .name = "hash", + .ops = &nft_hash_ops, + .policy = nft_hash_policy, + .maxattr = NFTA_HASH_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_hash_module_init(void) +{ + return nft_register_expr(&nft_hash_type); +} + +static void __exit nft_hash_module_exit(void) +{ + nft_unregister_expr(&nft_hash_type); +} + +module_init(nft_hash_module_init); +module_exit(nft_hash_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Laura Garcia "); +MODULE_ALIAS_NFT_EXPR("hash");