From patchwork Mon Dec 2 15:07:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 13890899 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-wm1-f42.google.com (mail-wm1-f42.google.com [209.85.128.42]) (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 ECE9E208974 for ; Mon, 2 Dec 2024 15:08:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733152132; cv=none; b=mRRyS1moqLGLq3DM/Mg25ZH6EgkozGFD9Glg3kIIR9auGAc5+koyVTTJ4ulBTwTggX0fSwPA4fZK3nbOiaSV/RuiSf3zCZe1cRgFlIMWbcO8f2rauqVyJNeymf6Lmb2/v3OpsaGJ/65/QPD8ZzNwyDYPPRW2tZ6ouyJQrOR/9NU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733152132; c=relaxed/simple; bh=2qIz2p0fw0aYKbtD0sIQmGm8WFwVQ83diG3BR3Bkayw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=dzYUleaCnH4VO1Vc60bEMGEmdgV3mATovSYjUXBDr807qPy3zyd837omxSWGK8hWPy7v2JddDUCv4alRRA7dJaT89IuTtSF143ed+FYJdjpqymTeOecegZVKyBIeraIklWnE5mojtnyZ15aLPJVfTi0i++1gmK0qVOJbi37GvPI= 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=FN3AD5/r; arc=none smtp.client-ip=209.85.128.42 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="FN3AD5/r" Received: by mail-wm1-f42.google.com with SMTP id 5b1f17b1804b1-434aabd688fso27888325e9.3 for ; Mon, 02 Dec 2024 07:08:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=openvpn.net; s=google; t=1733152127; x=1733756927; 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=ggaE+5wPjKoAPNX3M2/uy1Q8P5VYEq4W790qDE/hRZ4=; b=FN3AD5/rXZZy6pbg2EjNbUuS7YtP5skm9zCHdosYcFfBkpkNghwLzn21Pw7RYp+yeH FoWSjXfGONyUn1zKM7QoeRJVmmtKeQMykYNJfb2aeTPzj/R7S8BKATQb/GX5aRoANStx fHTW13ii33N5RG4HxH+biiHcDMBuFwJabtoi4k+QVZRm9nOj5ybbuUZdg/C8b+DZRuMo QfO0NL0RgXDePU0jS+7sJXqn9BMXpH2lxn7VBBstj4BXhS0ImKUW20GKaiaYLDLfqfD2 fNTiG0xMKsIheJClAVrfKO2KPjoQDnUENkwYDRQPhGa1xokEefQOPVd67rNhpwajvfVv 5buQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733152127; x=1733756927; 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=ggaE+5wPjKoAPNX3M2/uy1Q8P5VYEq4W790qDE/hRZ4=; b=e1kshQ0Unqm8dg/3vVg7QBCFlmj06KLfpCd8DLVL8b3cxAK+wQRO11UljgFy+X8Cb+ JkEagOURE7TvbxXK9px0CX3liGlSFuSZcBJM2/gpDyCYjgqBnHek1OLD8mufyuxnNDSn f2JaALExlD+TTaCIOUqhS6kxpmzjzNM0RwAvANVJhOUalnqSmfYkjLUn9NwxxzeLT4Lh QtusnlGIvLUsW0hIsXx+4P63OPVd+Ucqytc0+wwYBcV8cCnkF2J8qlSGWz+cyUqgq3Dv sMCZqQQaAXd/Sg0FuOuIimtf8pD4JSZ7UC8eXwxY/L59fDFM2lCiObPddBGsiaRce3iU CXag== X-Forwarded-Encrypted: i=1; AJvYcCXB7XSOpGV53SA5sZUh3evEK4PLtCp7pvq0uiW8g5QWoYG5WSHWagWY0qgpuHClowAbpgYOvbQ=@vger.kernel.org X-Gm-Message-State: AOJu0YxLjVlle8OZJovZL+tsTZrBns1W8/yN5yLvlq9Og8SiD9u0Tq5H nA82XuDGTUqIh34/kDGkvb/HSA4Pa+L4tj0JuK5pUeerFSG6q9fEj+y68TO0GXE= X-Gm-Gg: ASbGncujFDPTPKiu6t/DlAxs7kBceHgK/wn3nAmRu9dxlTRNve1pXPVVXQ0ABT7Xbqp 6gTX5eo9QA+BnuI3yaBL1pEyBkvdKmbWN7orrn1YVeinpI6/PMEMOB4fmX88QIfxt+jMDniFXu7 9yPFwCX0LxN6ySg1sTmXYSaf2A8o9wBf48lbusShnBrSvz0tjPnF0CdeRDIyXXRgTP6RRYVSHux B6AUnm1TdVOBrnN7HwEQ7jn5Ucfl1D9tr3MGZKSfKrsT4PTTzUcBchyWuJp X-Google-Smtp-Source: AGHT+IGxU/XR/Upr3Ab3tRhInXYUac1ex6IqqewbVOYRCK/zO7zwNTyK13wjuJmQxIQzGY92MKeCDQ== X-Received: by 2002:a05:600c:4fcf:b0:431:60ec:7a91 with SMTP id 5b1f17b1804b1-434a9dbbd8amr215126495e9.2.1733152123969; Mon, 02 Dec 2024 07:08:43 -0800 (PST) Received: from serenity.mandelbit.com ([2001:67c:2fbc:1:5d0b:f507:fa8:3b2e]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-385e8a47032sm6570395f8f.51.2024.12.02.07.08.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Dec 2024 07:08:43 -0800 (PST) From: Antonio Quartulli Date: Mon, 02 Dec 2024 16:07:34 +0100 Subject: [PATCH net-next v12 16/22] ovpn: add support for peer floating Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241202-b4-ovpn-v12-16-239ff733bf97@openvpn.net> References: <20241202-b4-ovpn-v12-0-239ff733bf97@openvpn.net> In-Reply-To: <20241202-b4-ovpn-v12-0-239ff733bf97@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: Simon Horman , 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=10598; i=antonio@openvpn.net; h=from:subject:message-id; bh=2qIz2p0fw0aYKbtD0sIQmGm8WFwVQ83diG3BR3Bkayw=; b=owEBbQGS/pANAwAIAQtw5TqgONWHAcsmYgBnTc1neKSW/LerriMkWx6f0I6646POr/Gp3GkM/ /La6SOLQ32JATMEAAEIAB0WIQSZq9xs+NQS5N5fwPwLcOU6oDjVhwUCZ03NZwAKCRALcOU6oDjV h9iKB/9uH09Orsfl/Md5gU4hmP0SEEOUPSnsCqOiGqKBuomIGpfNtYd+K/0WEQgx6a5etHAn6NH Z7dDO1lj1Tncz+vRkS6bcAPc84K/XJm9gw3+yK1U/f4tz2J+G9tJKZqpzHAwm0PHEmQF0VYMndw sFHFKat73UAeZqQFsr/pcgApn2Y651wBpqUduGE/A6OQBWkMKh7ehrEEDdCWv22yU3gI3iowfI1 IMshQdqAs5otc6SySM7bfq/0mkSlEkVD8fy0jDob+2R7RKC4+bHbw7IZqWWNrJjbn0lgqO+VnnS J8/0NXRBcMAtDZ+gONOXEQ/Xj9sOGqvhAb0hF+gpIgX9+rQx X-Developer-Key: i=antonio@openvpn.net; a=openpgp; fpr=CABDA1282017C267219885C748F0CCB68F59D14C X-Patchwork-Delegate: kuba@kernel.org A peer connected via UDP may change its IP address without reconnecting (float). Add support for detecting and updating the new peer IP/port in case of floating. Signed-off-by: Antonio Quartulli --- drivers/net/ovpn/bind.c | 9 +- drivers/net/ovpn/io.c | 4 + drivers/net/ovpn/peer.c | 237 +++++++++++++++++++++++++++++++++++++----------- drivers/net/ovpn/peer.h | 3 +- 4 files changed, 190 insertions(+), 63 deletions(-) diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c index b4d2ccec2ceddf43bc445b489cc62a578ef0ad0a..c8ca340cca936a357409e9458807f27831511975 100644 --- a/drivers/net/ovpn/bind.c +++ b/drivers/net/ovpn/bind.c @@ -48,11 +48,8 @@ struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss) */ void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new) { - struct ovpn_bind *old; + lockdep_assert_held(&peer->lock); - spin_lock_bh(&peer->lock); - old = rcu_replace_pointer(peer->bind, new, true); - spin_unlock_bh(&peer->lock); - - kfree_rcu(old, rcu); + kfree_rcu(rcu_replace_pointer(peer->bind, new, + lockdep_is_held(&peer->lock)), rcu); } diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index bad6c0782802a993e6da04ecc1629ffd3ec59f62..ee3bb650ed4700d8fa2c9a128b6d2318e1653f5c 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -135,6 +135,10 @@ void ovpn_decrypt_post(void *data, int ret) /* keep track of last received authenticated packet for keepalive */ WRITE_ONCE(peer->last_recv, ktime_get_real_seconds()); + if (peer->sock->sock->sk->sk_protocol == IPPROTO_UDP) + /* check if this peer changed local or remote endpoint */ + ovpn_peer_endpoints_update(peer, skb); + /* point to encapsulated IP packet */ __skb_pull(skb, payload_offset); diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c index 7df9fedd593a74e2349922557ce299a0fcf03038..8c5643ca497f78282d6171a8ddbe9896cccef7ed 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -94,6 +94,188 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id) return peer; } +/** + * ovpn_peer_reset_sockaddr - recreate binding for peer + * @peer: peer to recreate the binding for + * @ss: sockaddr to use as remote endpoint for the binding + * @local_ip: local IP for the binding + * + * Return: 0 on success or a negative error code otherwise + */ +static int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer, + const struct sockaddr_storage *ss, + const u8 *local_ip) +{ + struct ovpn_bind *bind; + size_t ip_len; + + lockdep_assert_held(&peer->lock); + + /* create new ovpn_bind object */ + bind = ovpn_bind_from_sockaddr(ss); + if (IS_ERR(bind)) + return PTR_ERR(bind); + + if (local_ip) { + if (ss->ss_family == AF_INET) { + ip_len = sizeof(struct in_addr); + } else if (ss->ss_family == AF_INET6) { + ip_len = sizeof(struct in6_addr); + } else { + net_dbg_ratelimited("%s: invalid family %u for remote endpoint for peer %u\n", + netdev_name(peer->ovpn->dev), + ss->ss_family, peer->id); + kfree(bind); + return -EINVAL; + } + + memcpy(&bind->local, local_ip, ip_len); + } + + /* set binding */ + ovpn_bind_reset(peer, bind); + + return 0; +} + +#define ovpn_get_hash_slot(_key, _key_len, _tbl) ({ \ + typeof(_tbl) *__tbl = &(_tbl); \ + jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl); \ +}) + +#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl = &(_tbl); \ + &(*__tbl)[ovpn_get_hash_slot(_key, _key_len, *__tbl)]; \ +}) + +/** + * ovpn_peer_endpoints_update - update remote or local endpoint for peer + * @peer: peer to update the remote endpoint for + * @skb: incoming packet to retrieve the source/destination address from + */ +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb) +{ + struct hlist_nulls_head *nhead; + struct sockaddr_storage ss; + const u8 *local_ip = NULL; + struct sockaddr_in6 *sa6; + struct sockaddr_in *sa; + struct ovpn_bind *bind; + size_t salen = 0; + + spin_lock_bh(&peer->lock); + bind = rcu_dereference_protected(peer->bind, + lockdep_is_held(&peer->lock)); + if (unlikely(!bind)) + goto unlock; + + switch (skb->protocol) { + case htons(ETH_P_IP): + /* float check */ + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) { + if (bind->remote.in4.sin_family == AF_INET) + local_ip = (u8 *)&bind->local; + sa = (struct sockaddr_in *)&ss; + sa->sin_family = AF_INET; + sa->sin_addr.s_addr = ip_hdr(skb)->saddr; + sa->sin_port = udp_hdr(skb)->source; + salen = sizeof(*sa); + break; + } + + /* local endpoint update */ + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", + netdev_name(peer->ovpn->dev), + peer->id, &bind->local.ipv4.s_addr, + &ip_hdr(skb)->daddr); + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; + } + break; + case htons(ETH_P_IPV6): + /* float check */ + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) { + if (bind->remote.in6.sin6_family == AF_INET6) + local_ip = (u8 *)&bind->local; + sa6 = (struct sockaddr_in6 *)&ss; + sa6->sin6_family = AF_INET6; + sa6->sin6_addr = ipv6_hdr(skb)->saddr; + sa6->sin6_port = udp_hdr(skb)->source; + sa6->sin6_scope_id = ipv6_iface_scope_id(&ipv6_hdr(skb)->saddr, + skb->skb_iif); + salen = sizeof(*sa6); + } + + /* local endpoint update */ + if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, + &ipv6_hdr(skb)->daddr))) { + net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", + netdev_name(peer->ovpn->dev), + peer->id, &bind->local.ipv6, + &ipv6_hdr(skb)->daddr); + bind->local.ipv6 = ipv6_hdr(skb)->daddr; + } + break; + default: + goto unlock; + } + + /* if the peer did not float, we can bail out now */ + if (likely(!salen)) + goto unlock; + + if (unlikely(ovpn_peer_reset_sockaddr(peer, + (struct sockaddr_storage *)&ss, + local_ip) < 0)) + goto unlock; + + net_dbg_ratelimited("%s: peer %d floated to %pIScp", + netdev_name(peer->ovpn->dev), peer->id, &ss); + + spin_unlock_bh(&peer->lock); + + /* rehashing is required only in MP mode as P2P has one peer + * only and thus there is no hashtable + */ + if (peer->ovpn->mode == OVPN_MODE_MP) { + spin_lock_bh(&peer->ovpn->lock); + spin_lock_bh(&peer->lock); + bind = rcu_dereference_protected(peer->bind, + lockdep_is_held(&peer->lock)); + if (unlikely(!bind)) { + spin_unlock_bh(&peer->lock); + spin_unlock_bh(&peer->ovpn->lock); + return; + } + + /* his function may be invoked concurrently, therefore another + * float may have happened in parallel: perform rehashing + * using the peer->bind->remote directly as key + */ + + switch (bind->remote.in4.sin_family) { + case AF_INET: + salen = sizeof(*sa); + break; + case AF_INET6: + salen = sizeof(*sa6); + break; + } + + /* remove old hashing */ + hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr); + /* re-add with new transport address */ + nhead = ovpn_get_hash_head(peer->ovpn->peers->by_transp_addr, + &bind->remote, salen); + hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead); + spin_unlock_bh(&peer->lock); + spin_unlock_bh(&peer->ovpn->lock); + } + return; +unlock: + spin_unlock_bh(&peer->lock); +} + /** * ovpn_peer_release_rcu - RCU callback performing last peer release steps * @head: RCU member of the ovpn_peer @@ -197,16 +379,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb) return rt->rt6i_gateway; } -#define ovpn_get_hash_slot(_key, _key_len, _tbl) ({ \ - typeof(_tbl) *__tbl = &(_tbl); \ - jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl); \ -}) - -#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl = &(_tbl); \ - &(*__tbl)[ovpn_get_hash_slot(_key, _key_len, *__tbl)]; \ -}) - /** * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address * @ovpn: the openvpn instance to search @@ -450,51 +622,6 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id) return peer; } -/** - * ovpn_peer_update_local_endpoint - update local endpoint for peer - * @peer: peer to update the endpoint for - * @skb: incoming packet to retrieve the destination address (local) from - */ -void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, - struct sk_buff *skb) -{ - struct ovpn_bind *bind; - - rcu_read_lock(); - bind = rcu_dereference(peer->bind); - if (unlikely(!bind)) - goto unlock; - - spin_lock_bh(&peer->lock); - switch (skb->protocol) { - case htons(ETH_P_IP): - if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { - net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", - netdev_name(peer->ovpn->dev), - peer->id, &bind->local.ipv4.s_addr, - &ip_hdr(skb)->daddr); - bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; - } - break; - case htons(ETH_P_IPV6): - if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, - &ipv6_hdr(skb)->daddr))) { - net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", - netdev_name(peer->ovpn->dev), - peer->id, &bind->local.ipv6, - &ipv6_hdr(skb)->daddr); - bind->local.ipv6 = ipv6_hdr(skb)->daddr; - } - break; - default: - break; - } - spin_unlock_bh(&peer->lock); - -unlock: - rcu_read_unlock(); -} - /** * ovpn_peer_get_by_dst - Lookup peer to send skb to * @ovpn: the private data representing the current VPN session diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index 196fa0a04f2db1986fffa6d51b42b68c9837c8e8..a95ec054a8c2224cc0a4ef3800d30e76138f1fe6 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -153,7 +153,6 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb, void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout); void ovpn_peer_keepalive_work(struct work_struct *work); -void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, - struct sk_buff *skb); +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb); #endif /* _NET_OVPN_OVPNPEER_H_ */