From patchwork Thu Dec 14 22:49:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Xu X-Patchwork-Id: 13493780 X-Patchwork-Delegate: bpf@iogearbox.net Received: from wout1-smtp.messagingengine.com (wout1-smtp.messagingengine.com [64.147.123.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5CF126E2A4; Thu, 14 Dec 2023 22:49:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=dxuuu.xyz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=dxuuu.xyz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=dxuuu.xyz header.i=@dxuuu.xyz header.b="GSWv5A9B"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="c7pwMGAs" Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.west.internal (Postfix) with ESMTP id CB8F33200B64; Thu, 14 Dec 2023 17:49:21 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Thu, 14 Dec 2023 17:49:23 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dxuuu.xyz; h=cc :cc:content-transfer-encoding:content-type:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:subject:subject:to:to; s=fm3; t=1702594161; x= 1702680561; bh=ynqiDxPX3Efy/SYsYJAsJaqvlEj7twgQpz4HuNKHZPw=; b=G SWv5A9BtfOEGRfHe0tp9jmoZbRtjAu2SXhpN6Bf6p6Pv5zjOd3x/3/p1ZSOhug7B 1c09ZD3eloSoYWMVEOgujqoEM8BYWlleTushJWH/wMtx/qOrLnC0FPJCT1d8h6Y1 GqZLz3FL98MpROQJsHT2xPzEc26BA2q+GWsyMxSYghALTaj/uruqf8kjp1XhN4Ac HIp+cpl2+dFIAFJV1+T93j5Xl0qJw3rv1efvAIQfKVGpUsgG+Y/2GurXj+jTUKiF VeysALPEnLERxCMwjs2Bl2vvOC6EpGgLqY18Xywjd9lvfIUnDgbh7Qgcx/sLMOln zzdgM3as3neNfFD4VT4ZQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t=1702594161; x= 1702680561; bh=ynqiDxPX3Efy/SYsYJAsJaqvlEj7twgQpz4HuNKHZPw=; b=c 7pwMGAstp5oO4deeIxME8N5VDebShGUoB+yMwnqkF0qCNhoazWhKtVovzmZeE7xW n3baTezaHEvBTaG0z+xwT7Zp/BConBvMjSMSQmrpVt8HuMdDQ0IAt1g2fQBNwQVz Gt6KyrVMPi+0PKQ1s2bqUpT/2EVllz6KCOaFacpF6V6rAtiIocbM/FugbKHJMEYL 6NCQEoWoPqQjgmDZtrBJJqjHPRTtyE/gNqPeQ8naytRFKEwLbZP85qFnkKqYUdT8 ZWWpp4P8KhLrIhYHrCkc7TL1ayCmuoOwPSa2sF+f9W3UeTAZ3pFrNRwJfGu1DdGm jj0bB43e2CWtKgVaf2teA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrvddttddgtddvucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne gfrhhlucfvnfffucdlfeehmdenucfjughrpefhvfevufffkffojghfggfgsedtkeertder tddtnecuhfhrohhmpeffrghnihgvlhcuighuuceougiguhesugiguhhuuhdrgiihiieqne cuggftrfgrthhtvghrnhepgfefgfegjefhudeikedvueetffelieefuedvhfehjeeljeej kefgffeghfdttdetnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilh hfrhhomhepugiguhesugiguhhuuhdrgiihii X-ME-Proxy: Feedback-ID: i6a694271:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 14 Dec 2023 17:49:18 -0500 (EST) From: Daniel Xu To: davem@davemloft.net, hawk@kernel.org, Herbert Xu , kuba@kernel.org, edumazet@google.com, john.fastabend@gmail.com, ast@kernel.org, daniel@iogearbox.net, pabeni@redhat.com, steffen.klassert@secunet.com, antony.antony@secunet.com, alexei.starovoitov@gmail.com, yonghong.song@linux.dev, eddyz87@gmail.com, eyal.birger@gmail.com Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, devel@linux-ipsec.org Subject: [PATCH bpf-next v6 1/5] bpf: xfrm: Add bpf_xdp_get_xfrm_state() kfunc Date: Thu, 14 Dec 2023 15:49:02 -0700 Message-ID: X-Mailer: git-send-email 2.42.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net This commit adds an unstable kfunc helper to access internal xfrm_state associated with an SA. This is intended to be used for the upcoming IPsec pcpu work to assign special pcpu SAs to a particular CPU. In other words: for custom software RSS. That being said, the function that this kfunc wraps is fairly generic and used for a lot of xfrm tasks. I'm sure people will find uses elsewhere over time. This commit also adds a corresponding bpf_xdp_xfrm_state_release() kfunc to release the refcnt acquired by bpf_xdp_get_xfrm_state(). The verifier will require that all acquired xfrm_state's are released. Co-developed-by: Antony Antony Signed-off-by: Antony Antony Acked-by: Steffen Klassert Signed-off-by: Daniel Xu --- include/net/xfrm.h | 9 +++ net/xfrm/Makefile | 1 + net/xfrm/xfrm_policy.c | 2 + net/xfrm/xfrm_state_bpf.c | 134 ++++++++++++++++++++++++++++++++++++++ 4 files changed, 146 insertions(+) create mode 100644 net/xfrm/xfrm_state_bpf.c diff --git a/include/net/xfrm.h b/include/net/xfrm.h index c9bb0f892f55..1d107241b901 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -2190,4 +2190,13 @@ static inline int register_xfrm_interface_bpf(void) #endif +#if IS_ENABLED(CONFIG_DEBUG_INFO_BTF) +int register_xfrm_state_bpf(void); +#else +static inline int register_xfrm_state_bpf(void) +{ + return 0; +} +#endif + #endif /* _NET_XFRM_H */ diff --git a/net/xfrm/Makefile b/net/xfrm/Makefile index cd47f88921f5..547cec77ba03 100644 --- a/net/xfrm/Makefile +++ b/net/xfrm/Makefile @@ -21,3 +21,4 @@ obj-$(CONFIG_XFRM_USER_COMPAT) += xfrm_compat.o obj-$(CONFIG_XFRM_IPCOMP) += xfrm_ipcomp.o obj-$(CONFIG_XFRM_INTERFACE) += xfrm_interface.o obj-$(CONFIG_XFRM_ESPINTCP) += espintcp.o +obj-$(CONFIG_DEBUG_INFO_BTF) += xfrm_state_bpf.o diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index c13dc3ef7910..1b7e75159727 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -4218,6 +4218,8 @@ void __init xfrm_init(void) #ifdef CONFIG_XFRM_ESPINTCP espintcp_init(); #endif + + register_xfrm_state_bpf(); } #ifdef CONFIG_AUDITSYSCALL diff --git a/net/xfrm/xfrm_state_bpf.c b/net/xfrm/xfrm_state_bpf.c new file mode 100644 index 000000000000..9e20d4a377f7 --- /dev/null +++ b/net/xfrm/xfrm_state_bpf.c @@ -0,0 +1,134 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Unstable XFRM state BPF helpers. + * + * Note that it is allowed to break compatibility for these functions since the + * interface they are exposed through to BPF programs is explicitly unstable. + */ + +#include +#include +#include +#include +#include + +/* bpf_xfrm_state_opts - Options for XFRM state lookup helpers + * + * Members: + * @error - Out parameter, set for any errors encountered + * Values: + * -EINVAL - netns_id is less than -1 + * -EINVAL - opts__sz isn't BPF_XFRM_STATE_OPTS_SZ + * -ENONET - No network namespace found for netns_id + * -ENOENT - No xfrm_state found + * @netns_id - Specify the network namespace for lookup + * Values: + * BPF_F_CURRENT_NETNS (-1) + * Use namespace associated with ctx + * [0, S32_MAX] + * Network Namespace ID + * @mark - XFRM mark to match on + * @daddr - Destination address to match on + * @spi - Security parameter index to match on + * @proto - IP protocol to match on (eg. IPPROTO_ESP) + * @family - Protocol family to match on (AF_INET/AF_INET6) + */ +struct bpf_xfrm_state_opts { + s32 error; + s32 netns_id; + u32 mark; + xfrm_address_t daddr; + __be32 spi; + u8 proto; + u16 family; +}; + +enum { + BPF_XFRM_STATE_OPTS_SZ = sizeof(struct bpf_xfrm_state_opts), +}; + +__bpf_kfunc_start_defs(); + +/* bpf_xdp_get_xfrm_state - Get XFRM state + * + * A `struct xfrm_state *`, if found, must be released with a corresponding + * bpf_xdp_xfrm_state_release. + * + * Parameters: + * @ctx - Pointer to ctx (xdp_md) in XDP program + * Cannot be NULL + * @opts - Options for lookup (documented above) + * Cannot be NULL + * @opts__sz - Length of the bpf_xfrm_state_opts structure + * Must be BPF_XFRM_STATE_OPTS_SZ + */ +__bpf_kfunc struct xfrm_state * +bpf_xdp_get_xfrm_state(struct xdp_md *ctx, struct bpf_xfrm_state_opts *opts, u32 opts__sz) +{ + struct xdp_buff *xdp = (struct xdp_buff *)ctx; + struct net *net = dev_net(xdp->rxq->dev); + struct xfrm_state *x; + + if (!opts || opts__sz < sizeof(opts->error)) + return NULL; + + if (opts__sz != BPF_XFRM_STATE_OPTS_SZ) { + opts->error = -EINVAL; + return NULL; + } + + if (unlikely(opts->netns_id < BPF_F_CURRENT_NETNS)) { + opts->error = -EINVAL; + return NULL; + } + + if (opts->netns_id >= 0) { + net = get_net_ns_by_id(net, opts->netns_id); + if (unlikely(!net)) { + opts->error = -ENONET; + return NULL; + } + } + + x = xfrm_state_lookup(net, opts->mark, &opts->daddr, opts->spi, + opts->proto, opts->family); + + if (opts->netns_id >= 0) + put_net(net); + if (!x) + opts->error = -ENOENT; + + return x; +} + +/* bpf_xdp_xfrm_state_release - Release acquired xfrm_state object + * + * This must be invoked for referenced PTR_TO_BTF_ID, and the verifier rejects + * the program if any references remain in the program in all of the explored + * states. + * + * Parameters: + * @x - Pointer to referenced xfrm_state object, obtained using + * bpf_xdp_get_xfrm_state. + */ +__bpf_kfunc void bpf_xdp_xfrm_state_release(struct xfrm_state *x) +{ + xfrm_state_put(x); +} + +__bpf_kfunc_end_defs(); + +BTF_SET8_START(xfrm_state_kfunc_set) +BTF_ID_FLAGS(func, bpf_xdp_get_xfrm_state, KF_RET_NULL | KF_ACQUIRE) +BTF_ID_FLAGS(func, bpf_xdp_xfrm_state_release, KF_RELEASE) +BTF_SET8_END(xfrm_state_kfunc_set) + +static const struct btf_kfunc_id_set xfrm_state_xdp_kfunc_set = { + .owner = THIS_MODULE, + .set = &xfrm_state_kfunc_set, +}; + +int __init register_xfrm_state_bpf(void) +{ + return register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, + &xfrm_state_xdp_kfunc_set); +}