From patchwork Wed Mar 12 20:54:26 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Antonio Quartulli X-Patchwork-Id: 14013874 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-wr1-f45.google.com (mail-wr1-f45.google.com [209.85.221.45]) (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 A1F031F4265 for ; Wed, 12 Mar 2025 20:54:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.45 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741812893; cv=none; b=MPh1c+ToQiNtxt1FBAPlv4Kt2UOJeOFDud1iWAp2bt/weejLcg4MfItLBxp45uqd4Jy8kg6QoBMu6q+zsahXbdzxhGJjfUisBIRqe43tsDoCZdfnN6tGwnP1cOYNq2mwsHts4spjxqAiTtgYR9CSTgijuTP8MTgSKaMbn4ciQMI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741812893; c=relaxed/simple; bh=hWDVMOTtTG8kzSL7EXcquGSgf8JSTQqIzV4s/5vY758=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Bs5WO3tufVXHKb6S/7BeoTv9UKJQ5R3Y2KqAZdKkOxGIEAX+SbUd+T2xY+iR2+gCcBdHSc+rWBWBpJ98NfIrbSBeNXzfqtI3QlHl46ut2z+7RLMC14AOaN9KMZeQ8Cfqgz0cMxHxsbeg8v7I1PVYbXleTnu4fCeRuvWKU5Qnbus= 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=UANyCwD0; arc=none smtp.client-ip=209.85.221.45 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="UANyCwD0" Received: by mail-wr1-f45.google.com with SMTP id ffacd0b85a97d-3913958ebf2so204841f8f.3 for ; Wed, 12 Mar 2025 13:54:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=openvpn.net; s=google; t=1741812888; x=1742417688; 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=/SdaijiYImbVHQ86OLZGBo8ZqPFKIkT8IkG7Vksf3us=; b=UANyCwD0CJQXLWt9V3E6a5Ef8MAX5h+A5HqlxRuDGuTW4Qjqg3YlfWrfu0ah079enV SD+y/TCt8Gy6Ni9DLb0Yx9cCVC+17yAejuabfxiVGSi17djgkaSOthugSzbjOOUliZ0m Jkm6LYtZzX+Q3+uBt+SbkmYqOMM8UIIfteVOTJMvJhPC1ZrTWCoYr35WHINareJ8wrZt +Wpld7cuAoPSokbtERrIo9PZQXnzX/948sUlXwkyevGvaZnz+ti9IJymhtErtOrRbh7j qK5xigBKG8A2UQ58xkeAuNry9EyWaWmT8smxXEvzcKm3BfTaWq4apOu92SvUgnk41o3k p9cQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741812888; x=1742417688; 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=/SdaijiYImbVHQ86OLZGBo8ZqPFKIkT8IkG7Vksf3us=; b=dEtsdCuq6mccrGwwY8FG04xgxogDCjZuj6MMAz+qfmUgxSKZ3y9odt3W20+3fmGHL+ rB3TjjlHQNBMGkmCZcLlSByK0Kq13FEr6RtqMFdXuxA9VuBrvygeM07XU6O7RaOaR6ih IblXp7vlf4CXFwAK+wp7AsWfqpOy82EMLY7u5FWBRSOqVfbzsbn80XmpSPNdS3k2jU8b oyWsdIYtueORDJTzwaiCLMCTupsH2XE1dyX/8AGh2zv0fJ12CX2i3ImYLBFP3WEyNqZt 9VAazM//lZGIkPDQaXFKxtm4YlB7ou7D6UXSn7POjd3dW2Vo4xIiURDM+tSxXa1m2vV8 qofA== X-Gm-Message-State: AOJu0YylT/U4G2WRGxCAElYXykzf3O0rRFHIrPzZ7DPhhi+itNa0y7WQ 27FFrn6RkWBOf1gswnQmkNXhpxHUPb5uSwTqJu1tFmAqAy+ZoolsxLinMiBPQA0= X-Gm-Gg: ASbGncuEBFEJb/TvmRusPoiAFj6fQQsB1WYNRtulCGHodQ4AyLMSeJpcLr6Qoo3HOIc 9EcwVX2PHTITymAKUXbKse6tlHb8gUTXt4ewIwC9Cg24qoPNv66etGFI10qmc1FSEMjxq/sB2ah eUs3NSpFKtueNYELC4O1XGCk5v5rm0OhgpSzbqlCC/ivM4vsMchKfYsUZHmUpsnI5S5eNz7vOxo qnwyTeOsvXeyiGxb/mNRXmzHGCzrwyqkTWq5L4ClVVPWVUziPpf56qYSLJXRj20Gkavrb7JSsjy fu/f76rb+3cG10COhUrrDnihf4Qq+CIT0Siu9Pwd0Q== X-Google-Smtp-Source: AGHT+IEIjZBrZLR7o1/5Uo8t96QaHtKgyrWfAk/pZSQ9bv2baUEbjrJwvtnWBw51zKuBZemh3TG56g== X-Received: by 2002:a05:6000:4022:b0:391:31c8:ba59 with SMTP id ffacd0b85a97d-39263ceba19mr7016928f8f.4.1741812887676; Wed, 12 Mar 2025 13:54:47 -0700 (PDT) Received: from [127.0.0.1] ([2001:67c:2fbc:1:a42b:bae6:6f7d:117f]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3912c10437dsm22481393f8f.99.2025.03.12.13.54.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Mar 2025 13:54:46 -0700 (PDT) From: Antonio Quartulli Date: Wed, 12 Mar 2025 21:54:26 +0100 Subject: [PATCH net-next v23 17/23] ovpn: add support for updating local or remote UDP endpoint Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250312-b4-ovpn-v23-17-76066bc0a30c@openvpn.net> References: <20250312-b4-ovpn-v23-0-76066bc0a30c@openvpn.net> In-Reply-To: <20250312-b4-ovpn-v23-0-76066bc0a30c@openvpn.net> To: netdev@vger.kernel.org, Eric Dumazet , Jakub Kicinski , Paolo Abeni , Donald Hunter , Antonio Quartulli , Shuah Khan , sd@queasysnail.net, ryazanov.s.a@gmail.com, Andrew Lunn Cc: Simon Horman , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Xiao Liang X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=9204; i=antonio@openvpn.net; h=from:subject:message-id; bh=hWDVMOTtTG8kzSL7EXcquGSgf8JSTQqIzV4s/5vY758=; b=owEBbQGS/pANAwAIAQtw5TqgONWHAcsmYgBn0fR82Y6OxHi/b7+1T1nbDp6LDACe2q3IY1KYs IDKEGto77eJATMEAAEIAB0WIQSZq9xs+NQS5N5fwPwLcOU6oDjVhwUCZ9H0fAAKCRALcOU6oDjV h4QgCACsGdqWUzZAYxkOv/iYkEhm8k69MxTQxOdJWKRe93ZcMLL+d7UcxkVmBkd5pgE2LIyO4DR PAJLo3CgcJRxPIGYXPii0Tk23y9FSM7qgRiNNlnIEhilK3w+3gDt8V8PeK8pAuMvy2D7ec37Fhv AGnqTrzntA+mUWElrVjy3ptEY4CWjhr/43xYV9iYSvzmsXDdrPRr1SI3sHCM/Y8s8TsGqzwZJNH ENm6Ey/sANukEDyvqS2WL9dzAUilIymeo0P0G4ni8VO3F6K91NO0RS/nUCRWlS6dP6lk+Gmy/Fn 5MeZC4RUegDPtWqiQNNEvgtOLzrdCcAMM8R0/lln4g27eVDM X-Developer-Key: i=antonio@openvpn.net; a=openpgp; fpr=CABDA1282017C267219885C748F0CCB68F59D14C X-Patchwork-Delegate: kuba@kernel.org In case of UDP links, the local or remote endpoint used to communicate with a given peer may change without a connection restart. Add support for learning the new address in case of change. Signed-off-by: Antonio Quartulli --- drivers/net/ovpn/io.c | 8 ++ drivers/net/ovpn/peer.c | 213 +++++++++++++++++++++++++++++++++++++++++++++--- drivers/net/ovpn/peer.h | 2 + 3 files changed, 210 insertions(+), 13 deletions(-) diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index 6ee1a40082ef637285d7f7f8183c53140583b716..5b673eae255033b9d7d6e7890a46686403d7c222 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -96,6 +96,7 @@ void ovpn_decrypt_post(void *data, int ret) struct ovpn_crypto_key_slot *ks; unsigned int payload_offset = 0; struct sk_buff *skb = data; + struct ovpn_socket *sock; struct ovpn_peer *peer; __be16 proto; __be32 *pid; @@ -137,6 +138,13 @@ 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()); + rcu_read_lock(); + sock = rcu_dereference(peer->sock); + if (sock && sock->sock->sk->sk_protocol == IPPROTO_UDP) + /* check if this peer changed local or remote endpoint */ + ovpn_peer_endpoints_update(peer, skb); + rcu_read_unlock(); + /* 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 45e87ac155b554044388490a403f64c777d283a6..0d8b12fd5de4cd6fe15455b435c7d6807203a825 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -127,6 +127,206 @@ 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 void *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 (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; +} + +/* variable name __tbl2 needs to be different from __tbl1 + * in the macro below to avoid confusing clang + */ +#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl2 = &(_tbl); \ + jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \ +}) + +#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ + typeof(_tbl) *__tbl1 = &(_tbl); \ + &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\ +}) + +/** + * 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; + struct sockaddr_in6 *sa6; + bool reset_cache = false; + struct sockaddr_in *sa; + struct ovpn_bind *bind; + const void *local_ip; + 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))) { + /* unconditionally save local endpoint in case + * of float, as it may have changed as well + */ + local_ip = &ip_hdr(skb)->daddr; + 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); + reset_cache = true; + break; + } + + /* if no float happened, let's double check if the local endpoint + * has changed + */ + 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; + reset_cache = true; + } + break; + case htons(ETH_P_IPV6): + /* float check */ + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) { + /* unconditionally save local endpoint in case + * of float, as it may have changed as well + */ + local_ip = &ipv6_hdr(skb)->daddr; + 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); + reset_cache = true; + break; + } + + /* if no float happened, let's double check if the local endpoint + * has changed + */ + 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; + reset_cache = true; + } + break; + default: + goto unlock; + } + + if (unlikely(reset_cache)) + dst_cache_reset(&peer->dst_cache); + + /* 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; + } + + /* This 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 @@ -230,19 +430,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb) return rt->rt6i_gateway; } -/* variable name __tbl2 needs to be different from __tbl1 - * in the macro below to avoid confusing clang - */ -#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl2 = &(_tbl); \ - jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \ -}) - -#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \ - typeof(_tbl) *__tbl1 = &(_tbl); \ - &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\ -}) - /** * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address * @ovpn: the openvpn instance to search diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h index e747c4b210642db990222986a80bb37c9a0413fe..f1288734ff100ee76b0c41ebb6dc71725ea33261 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -153,4 +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_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb); + #endif /* _NET_OVPN_OVPNPEER_H_ */