From nobody Mon Nov 25 20:29:10 2024 Received: from mail-lf1-f41.google.com (mail-lf1-f41.google.com [209.85.167.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBDF91D26E7 for ; Fri, 25 Oct 2024 09:15:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.41 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729847712; cv=none; b=RFyS0IjhWU5eVEnqbkt2wqpbAh49gaFiwLKcDAHsoq1VPtzBqK6kUwantz96NBZ/PkHO2YKbH81GrNI/05YNd5cvgGb/PopnSIXTDzOGAGRffZDcIrVq6BU7UpcISt8rGqDl/tSk2y+OtGUjHnti83fhy2UAoaVTTwf3pdvG4u8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729847712; c=relaxed/simple; bh=YMuwyTMzclpNnNaR/WkRJmXnCptZu+Rq2A1hloxGEmY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=FjiveImQrx+IV77QxEci/z1PcdZnWeLfVxkOAa6rq5EtDkWbF49aB+2SkOX7ZCRiA/JF1f9xxbNhqdDyBPjOFYXCkkA6X2Yxy6y6BGFd4tByA3ONGAxSLbGwMZX54zCdVUiFGmNF4i5oGr6j25rLP5CHT5KqoZ3KyJs6cNRw0Bo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=openvpn.net; spf=pass smtp.mailfrom=openvpn.com; dkim=pass (2048-bit key) header.d=openvpn.net header.i=@openvpn.net header.b=Nsfd5Wvb; arc=none smtp.client-ip=209.85.167.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=openvpn.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=openvpn.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=openvpn.net header.i=@openvpn.net header.b="Nsfd5Wvb" Received: by mail-lf1-f41.google.com with SMTP id 2adb3069b0e04-539e3f35268so2322601e87.3 for ; Fri, 25 Oct 2024 02:15:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=openvpn.net; s=google; t=1729847704; x=1730452504; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=rEkhq4g07rH6eS4QvsCkWBw8nlVl5m3JneNiJjlmb24=; b=Nsfd5WvbeqednIl6ESirM+ag72b0uv4bPfq03iL0PbdP6oj/MklG5xZ4NFDST880+O hGtzvGmJqPZaLMwu4V9mcqq5lha7PklzppImERjaVpRVjVK3NeWMq4TRYKyTNRP68Hjc zpXTJf/YN6Vn/bPV+7fIqiSQHDF03ZklaiddO13ih0bG36+3qAODL3yU/MKzXjdCLt/n tP14/0R49l2fWOb2zz0h8GEL+dqnELjYFmcA6znFUg4FbdQcrxQ6ZuEDeXUcH/iosLHE WfR0/7+8OZxqLYU45Er4YopLuDgQ4Chxq+Xxw0VLX8SCI04KY5kHFY5af++ggexXhqZm ESaA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729847704; x=1730452504; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=rEkhq4g07rH6eS4QvsCkWBw8nlVl5m3JneNiJjlmb24=; b=ts6JE60E11fnjFcc8L4FTDl8zOPi0oTE/1V8/3v62BYHXCupLhXKtqgx034LzAZHq/ fZUZ2JVNZkPeLWnwUUWE5dpUl2d4jTY6b/sCAgehEvFQZgU2wetQ18n3B/xDxlQFDRT9 ls2ogmQp91af/mQGzrussnP8aG9e3iujGDj5Dal8Q54jEIPj30C1l3VLbmD4Is4OEPL3 94zmMYIbA4TX0DAlEHjHMT66r/7yw0P4fo5KwpCG3Glz9TFRJrkB4jFUbd9getvMjJ66 j73YJDAZ+nVJVQAjbBo+25V146TiXWXJLX3+S8XRmtAMAXT7eVE0LFzgDEz3fwYl0GX8 j3nQ== X-Forwarded-Encrypted: i=1; AJvYcCVXhUkKvo4rtsoBshAu0OD6CW8ug5co2e+7/HhemWrzIW+IUh360z6miJDakO5gz1uXN5Dv6pYlWGp3GOk=@vger.kernel.org X-Gm-Message-State: AOJu0Yx05P9mXvm4fnVFcxvdIFISs1xhTclQ7yhlU6kanAQ/MrAjPhrx t8eGpKT9YVfyrdzNzqu0DXELnw7lqH11j3rmJphXvgQCk1VX3yhpUqsE8BiUpa8= X-Google-Smtp-Source: AGHT+IGz/7XpSaFuXHGDod6bLAxOG1gDXN3/OEhG27ysFnnukFeqWuZJ4a+09JivbVON6DHw0ClJLw== X-Received: by 2002:a05:6512:1586:b0:539:89a8:5fe8 with SMTP id 2adb3069b0e04-53b1a30f7c5mr5605563e87.29.1729847703649; Fri, 25 Oct 2024 02:15:03 -0700 (PDT) Received: from serenity.mandelbit.com ([2001:67c:2fbc:1:676b:7d84:55a4:bea5]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4318b55f484sm41981485e9.13.2024.10.25.02.15.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 25 Oct 2024 02:15:03 -0700 (PDT) From: Antonio Quartulli Date: Fri, 25 Oct 2024 11:14:07 +0200 Subject: [PATCH net-next v10 08/23] ovpn: implement basic TX path (UDP) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241025-b4-ovpn-v10-8-b87530777be7@openvpn.net> References: <20241025-b4-ovpn-v10-0-b87530777be7@openvpn.net> In-Reply-To: <20241025-b4-ovpn-v10-0-b87530777be7@openvpn.net> To: Eric Dumazet , Jakub Kicinski , Paolo Abeni , Donald Hunter , Antonio Quartulli , Shuah Khan , donald.hunter@gmail.com, sd@queasysnail.net, ryazanov.s.a@gmail.com, Andrew Lunn Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=16921; i=antonio@openvpn.net; h=from:subject:message-id; bh=YMuwyTMzclpNnNaR/WkRJmXnCptZu+Rq2A1hloxGEmY=; b=owEBbQGS/pANAwAIAQtw5TqgONWHAcsmYgBnG2GZv4WHJHs+gVGNVZA4evpBY7av61G8B7JHc 9/pt/AAzpmJATMEAAEIAB0WIQSZq9xs+NQS5N5fwPwLcOU6oDjVhwUCZxthmQAKCRALcOU6oDjV h+7rCAC0XahbR+dSo5XvCiG8krDko3I3jhqIsx2U4wp1zZU8CNpostuMFR7TK8UGcpP5XAeB4VH 6P1lpwtuYwj/j81Vn4IsErXPY4RlgFMA1CRKvaq0yBqwh2KQNJSsP3K5VGuwn9d/IKuDcdXAbSK 2+Ayzd6SJqh0YgWLOIXwxK6s/l2O+/EYGeiGF0FJB4z7P+pQnb6htpEVrhI4vcEkYOkA7T0Qzom KTuJrJO03sB+0mLOSzAMjAessaksOjAAhVvf4gUk9BGgfYfoN2wghqj5FpWo7WYPtYsxJV7LwS3 0ZyRYmGezItYMI+TNwGih6RNntWxBq0tu8tvSipXZV4lzO5d X-Developer-Key: i=antonio@openvpn.net; a=openpgp; fpr=CABDA1282017C267219885C748F0CCB68F59D14C Packets sent over the ovpn interface are processed and transmitted to the connected peer, if any. Implementation is UDP only. TCP will be added by a later patch. Note: no crypto/encapsulation exists yet. packets are just captured and sent. Signed-off-by: Antonio Quartulli --- drivers/net/ovpn/io.c | 138 +++++++++++++++++++++++++++- drivers/net/ovpn/peer.c | 37 +++++++- drivers/net/ovpn/peer.h | 4 + drivers/net/ovpn/skb.h | 51 +++++++++++ drivers/net/ovpn/udp.c | 232 ++++++++++++++++++++++++++++++++++++++++++++= ++++ drivers/net/ovpn/udp.h | 8 ++ 6 files changed, 468 insertions(+), 2 deletions(-) diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index ad3813419c33cbdfe7e8ad6f5c8b444a3540a69f..77ba4d33ae0bd2f52e8bd1c06a1= 82d24285297b4 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -9,14 +9,150 @@ =20 #include #include +#include =20 #include "io.h" +#include "ovpnstruct.h" +#include "peer.h" +#include "udp.h" +#include "skb.h" +#include "socket.h" + +static void ovpn_encrypt_post(struct sk_buff *skb, int ret) +{ + struct ovpn_peer *peer =3D ovpn_skb_cb(skb)->peer; + + if (unlikely(ret < 0)) + goto err; + + skb_mark_not_on_list(skb); + + switch (peer->sock->sock->sk->sk_protocol) { + case IPPROTO_UDP: + ovpn_udp_send_skb(peer->ovpn, peer, skb); + break; + default: + /* no transport configured yet */ + goto err; + } + /* skb passed down the stack - don't free it */ + skb =3D NULL; +err: + if (unlikely(skb)) + dev_core_stats_tx_dropped_inc(peer->ovpn->dev); + ovpn_peer_put(peer); + kfree_skb(skb); +} + +static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb) +{ + ovpn_skb_cb(skb)->peer =3D peer; + + /* take a reference to the peer because the crypto code may run async. + * ovpn_encrypt_post() will release it upon completion + */ + if (unlikely(!ovpn_peer_hold(peer))) { + DEBUG_NET_WARN_ON_ONCE(1); + return false; + } + + ovpn_encrypt_post(skb, 0); + return true; +} + +/* send skb to connected peer, if any */ +static void ovpn_send(struct ovpn_struct *ovpn, struct sk_buff *skb, + struct ovpn_peer *peer) +{ + struct sk_buff *curr, *next; + + if (likely(!peer)) + /* retrieve peer serving the destination IP of this packet */ + peer =3D ovpn_peer_get_by_dst(ovpn, skb); + if (unlikely(!peer)) { + net_dbg_ratelimited("%s: no peer to send data to\n", + ovpn->dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + goto drop; + } + + /* this might be a GSO-segmented skb list: process each skb + * independently + */ + skb_list_walk_safe(skb, curr, next) + if (unlikely(!ovpn_encrypt_one(peer, curr))) { + dev_core_stats_tx_dropped_inc(ovpn->dev); + kfree_skb(curr); + } + + /* skb passed over, no need to free */ + skb =3D NULL; +drop: + if (likely(peer)) + ovpn_peer_put(peer); + kfree_skb_list(skb); +} =20 /* Send user data to the network */ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev) { + struct ovpn_struct *ovpn =3D netdev_priv(dev); + struct sk_buff *segments, *curr, *next; + struct sk_buff_head skb_list; + __be16 proto; + int ret; + + /* reset netfilter state */ + nf_reset_ct(skb); + + /* verify IP header size in network packet */ + proto =3D ovpn_ip_check_protocol(skb); + if (unlikely(!proto || skb->protocol !=3D proto)) { + net_err_ratelimited("%s: dropping malformed payload packet\n", + dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + goto drop; + } + + if (skb_is_gso(skb)) { + segments =3D skb_gso_segment(skb, 0); + if (IS_ERR(segments)) { + ret =3D PTR_ERR(segments); + net_err_ratelimited("%s: cannot segment packet: %d\n", + dev->name, ret); + dev_core_stats_tx_dropped_inc(ovpn->dev); + goto drop; + } + + consume_skb(skb); + skb =3D segments; + } + + /* from this moment on, "skb" might be a list */ + + __skb_queue_head_init(&skb_list); + skb_list_walk_safe(skb, curr, next) { + skb_mark_not_on_list(curr); + + curr =3D skb_share_check(curr, GFP_ATOMIC); + if (unlikely(!curr)) { + net_err_ratelimited("%s: skb_share_check failed\n", + dev->name); + dev_core_stats_tx_dropped_inc(ovpn->dev); + continue; + } + + __skb_queue_tail(&skb_list, curr); + } + skb_list.prev->next =3D NULL; + + ovpn_send(ovpn, skb_list.next, NULL); + + return NETDEV_TX_OK; + +drop: skb_tx_error(skb); - kfree_skb(skb); + kfree_skb_list(skb); return NET_XMIT_DROP; } diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index d9788a0cc99b5839c466c35d1b2266cc6b95fb72..aff3e9e99b7d2dd2fa68484d9a3= 96d43f75a6d0b 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -16,6 +16,7 @@ #include "main.h" #include "netlink.h" #include "peer.h" +#include "socket.h" =20 /** * ovpn_peer_new - allocate and initialize a new peer object @@ -64,8 +65,10 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn= , u32 id) */ static void ovpn_peer_release(struct ovpn_peer *peer) { - ovpn_bind_reset(peer, NULL); + if (peer->sock) + ovpn_socket_put(peer->sock); =20 + ovpn_bind_reset(peer, NULL); dst_cache_destroy(&peer->dst_cache); netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker); kfree_rcu(peer, rcu); @@ -243,6 +246,38 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_stru= ct *ovpn, u32 peer_id) return peer; } =20 +/** + * ovpn_peer_get_by_dst - Lookup peer to send skb to + * @ovpn: the private data representing the current VPN session + * @skb: the skb to extract the destination address from + * + * This function takes a tunnel packet and looks up the peer to send it to + * after encapsulation. The skb is expected to be the in-tunnel packet, wi= thout + * any OpenVPN related header. + * + * Assume that the IP header is accessible in the skb data. + * + * Return: the peer if found or NULL otherwise. + */ +struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn, + struct sk_buff *skb) +{ + struct ovpn_peer *peer =3D NULL; + + /* in P2P mode, no matter the destination, packets are always sent to + * the single peer listening on the other side + */ + if (ovpn->mode =3D=3D OVPN_MODE_P2P) { + rcu_read_lock(); + peer =3D rcu_dereference(ovpn->peer); + if (unlikely(peer && !ovpn_peer_hold(peer))) + peer =3D NULL; + rcu_read_unlock(); + } + + return peer; +} + /** * ovpn_peer_add_p2p - add peer to related tables in a P2P instance * @ovpn: the instance to add the peer to diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 6e0c6b14559de886d0677117f5a7ae029214e1f8..51955aa39f1aa85ce541e289c60= e9635cadb9c48 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -19,6 +19,7 @@ * @vpn_addrs: IP addresses assigned over the tunnel * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel + * @sock: the socket being used to talk to this peer * @dst_cache: cache for dst_entry used to send to peer * @bind: remote peer binding * @halt: true if ovpn_peer_mark_delete was called @@ -35,6 +36,7 @@ struct ovpn_peer { struct in_addr ipv4; struct in6_addr ipv6; } vpn_addrs; + struct ovpn_socket *sock; struct dst_cache dst_cache; struct ovpn_bind __rcu *bind; bool halt; @@ -75,5 +77,7 @@ void ovpn_peer_release_p2p(struct ovpn_struct *ovpn); struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn, struct sk_buff *skb); struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_i= d); +struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn, + struct sk_buff *skb); =20 #endif /* _NET_OVPN_OVPNPEER_H_ */ diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h new file mode 100644 index 0000000000000000000000000000000000000000..e070fe6f448c0b7a9631394ebef= 4554f6348ef44 --- /dev/null +++ b/drivers/net/ovpn/skb.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* OpenVPN data channel offload + * + * Copyright (C) 2020-2024 OpenVPN, Inc. + * + * Author: Antonio Quartulli + * James Yonan + */ + +#ifndef _NET_OVPN_SKB_H_ +#define _NET_OVPN_SKB_H_ + +#include +#include +#include +#include +#include +#include + +struct ovpn_cb { + struct ovpn_peer *peer; +}; + +static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct ovpn_cb) > sizeof(skb->cb)); + return (struct ovpn_cb *)skb->cb; +} + +/* Return IP protocol version from skb header. + * Return 0 if protocol is not IPv4/IPv6 or cannot be read. + */ +static inline __be16 ovpn_ip_check_protocol(struct sk_buff *skb) +{ + __be16 proto =3D 0; + + /* skb could be non-linear, + * make sure IP header is in non-fragmented part + */ + if (!pskb_network_may_pull(skb, sizeof(struct iphdr))) + return 0; + + if (ip_hdr(skb)->version =3D=3D 4) + proto =3D htons(ETH_P_IP); + else if (ip_hdr(skb)->version =3D=3D 6) + proto =3D htons(ETH_P_IPV6); + + return proto; +} + +#endif /* _NET_OVPN_SKB_H_ */ diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index c10474d252e19a0626d17a6f5dd328a5e5811551..d26d7566e9c8dfe91fa77f49c34= fb179a9fb2239 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -7,14 +7,246 @@ */ =20 #include +#include #include +#include +#include +#include +#include #include +#include =20 #include "ovpnstruct.h" #include "main.h" +#include "bind.h" +#include "io.h" +#include "peer.h" #include "socket.h" #include "udp.h" =20 +/** + * ovpn_udp4_output - send IPv4 packet over udp socket + * @ovpn: the openvpn instance + * @bind: the binding related to the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp4_output(struct ovpn_struct *ovpn, struct ovpn_bind *bi= nd, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + struct rtable *rt; + struct flowi4 fl =3D { + .saddr =3D bind->local.ipv4.s_addr, + .daddr =3D bind->remote.in4.sin_addr.s_addr, + .fl4_sport =3D inet_sk(sk)->inet_sport, + .fl4_dport =3D bind->remote.in4.sin_port, + .flowi4_proto =3D sk->sk_protocol, + .flowi4_mark =3D sk->sk_mark, + }; + int ret; + + local_bh_disable(); + rt =3D dst_cache_get_ip4(cache, &fl.saddr); + if (rt) + goto transmit; + + if (unlikely(!inet_confirm_addr(sock_net(sk), NULL, 0, fl.saddr, + RT_SCOPE_HOST))) { + /* we may end up here when the cached address is not usable + * anymore. In this case we reset address/cache and perform a + * new look up + */ + fl.saddr =3D 0; + bind->local.ipv4.s_addr =3D 0; + dst_cache_reset(cache); + } + + rt =3D ip_route_output_flow(sock_net(sk), &fl, sk); + if (IS_ERR(rt) && PTR_ERR(rt) =3D=3D -EINVAL) { + fl.saddr =3D 0; + bind->local.ipv4.s_addr =3D 0; + dst_cache_reset(cache); + + rt =3D ip_route_output_flow(sock_net(sk), &fl, sk); + } + + if (IS_ERR(rt)) { + ret =3D PTR_ERR(rt); + net_dbg_ratelimited("%s: no route to host %pISpc: %d\n", + ovpn->dev->name, &bind->remote.in4, ret); + goto err; + } + dst_cache_set_ip4(cache, &rt->dst, fl.saddr); + +transmit: + udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0, + ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport, + fl.fl4_dport, false, sk->sk_no_check_tx); + ret =3D 0; +err: + local_bh_enable(); + return ret; +} + +#if IS_ENABLED(CONFIG_IPV6) +/** + * ovpn_udp6_output - send IPv6 packet over udp socket + * @ovpn: the openvpn instance + * @bind: the binding related to the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp6_output(struct ovpn_struct *ovpn, struct ovpn_bind *bi= nd, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + struct dst_entry *dst; + int ret; + + struct flowi6 fl =3D { + .saddr =3D bind->local.ipv6, + .daddr =3D bind->remote.in6.sin6_addr, + .fl6_sport =3D inet_sk(sk)->inet_sport, + .fl6_dport =3D bind->remote.in6.sin6_port, + .flowi6_proto =3D sk->sk_protocol, + .flowi6_mark =3D sk->sk_mark, + .flowi6_oif =3D bind->remote.in6.sin6_scope_id, + }; + + local_bh_disable(); + dst =3D dst_cache_get_ip6(cache, &fl.saddr); + if (dst) + goto transmit; + + if (unlikely(!ipv6_chk_addr(sock_net(sk), &fl.saddr, NULL, 0))) { + /* we may end up here when the cached address is not usable + * anymore. In this case we reset address/cache and perform a + * new look up + */ + fl.saddr =3D in6addr_any; + bind->local.ipv6 =3D in6addr_any; + dst_cache_reset(cache); + } + + dst =3D ipv6_stub->ipv6_dst_lookup_flow(sock_net(sk), sk, &fl, NULL); + if (IS_ERR(dst)) { + ret =3D PTR_ERR(dst); + net_dbg_ratelimited("%s: no route to host %pISpc: %d\n", + ovpn->dev->name, &bind->remote.in6, ret); + goto err; + } + dst_cache_set_ip6(cache, dst, &fl.saddr); + +transmit: + udp_tunnel6_xmit_skb(dst, sk, skb, skb->dev, &fl.saddr, &fl.daddr, 0, + ip6_dst_hoplimit(dst), 0, fl.fl6_sport, + fl.fl6_dport, udp_get_no_check6_tx(sk)); + ret =3D 0; +err: + local_bh_enable(); + return ret; +} +#endif + +/** + * ovpn_udp_output - transmit skb using udp-tunnel + * @ovpn: the openvpn instance + * @bind: the binding related to the destination peer + * @cache: dst cache + * @sk: the socket to send the packet over + * @skb: the packet to send + * + * rcu_read_lock should be held on entry. + * On return, the skb is consumed. + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_udp_output(struct ovpn_struct *ovpn, struct ovpn_bind *bin= d, + struct dst_cache *cache, struct sock *sk, + struct sk_buff *skb) +{ + int ret; + + /* set sk to null if skb is already orphaned */ + if (!skb->destructor) + skb->sk =3D NULL; + + /* always permit openvpn-created packets to be (outside) fragmented */ + skb->ignore_df =3D 1; + + switch (bind->remote.in4.sin_family) { + case AF_INET: + ret =3D ovpn_udp4_output(ovpn, bind, cache, sk, skb); + break; +#if IS_ENABLED(CONFIG_IPV6) + case AF_INET6: + ret =3D ovpn_udp6_output(ovpn, bind, cache, sk, skb); + break; +#endif + default: + ret =3D -EAFNOSUPPORT; + break; + } + + return ret; +} + +/** + * ovpn_udp_send_skb - prepare skb and send it over via UDP + * @ovpn: the openvpn instance + * @peer: the destination peer + * @skb: the packet to send + */ +void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer, + struct sk_buff *skb) +{ + struct ovpn_bind *bind; + unsigned int pkt_len; + struct socket *sock; + int ret =3D -1; + + skb->dev =3D ovpn->dev; + /* no checksum performed at this layer */ + skb->ip_summed =3D CHECKSUM_NONE; + + /* get socket info */ + sock =3D peer->sock->sock; + if (unlikely(!sock)) { + net_warn_ratelimited("%s: no sock for remote peer\n", __func__); + goto out; + } + + rcu_read_lock(); + /* get binding */ + bind =3D rcu_dereference(peer->bind); + if (unlikely(!bind)) { + net_warn_ratelimited("%s: no bind for remote peer\n", __func__); + goto out_unlock; + } + + /* crypto layer -> transport (UDP) */ + pkt_len =3D skb->len; + ret =3D ovpn_udp_output(ovpn, bind, &peer->dst_cache, sock->sk, skb); + +out_unlock: + rcu_read_unlock(); +out: + if (unlikely(ret < 0)) { + dev_core_stats_tx_dropped_inc(ovpn->dev); + kfree_skb(skb); + return; + } + + dev_sw_netstats_tx_add(ovpn->dev, 1, pkt_len); +} + /** * ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ov= pn * @sock: socket to configure diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h index f2507f8f2c71ea9d5e5ac5446801e2d56f86700f..e60f8cd2b4ac8f910aabcf8ed54= 6af59d6ca4be4 100644 --- a/drivers/net/ovpn/udp.h +++ b/drivers/net/ovpn/udp.h @@ -9,9 +9,17 @@ #ifndef _NET_OVPN_UDP_H_ #define _NET_OVPN_UDP_H_ =20 +#include +#include + +struct ovpn_peer; struct ovpn_struct; +struct sk_buff; struct socket; =20 int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn); =20 +void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer, + struct sk_buff *skb); + #endif /* _NET_OVPN_UDP_H_ */ --=20 2.45.2