From patchwork Tue Jan 30 03:51:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Safonov X-Patchwork-Id: 13536821 Received: from mail-wr1-f53.google.com (mail-wr1-f53.google.com [209.85.221.53]) (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 D61FB381C6 for ; Tue, 30 Jan 2024 03:52:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.53 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706586728; cv=none; b=ZM1TqP9dMnY85iJtc1k7Jj2rKX20ne+eep5uh2Aci5ksUg73COe2OSumtjwmmNPrhF9FeVXaRC8sVvVEu3GHzgxlFHd8ua5/h4Cviu12o4GwSvnMXSOo9ZxkjPzkIe5d3Qfm2DNZfZG2VkLAdULRIuyGPm8ato04fTcuQC6+wiI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706586728; c=relaxed/simple; bh=DuT4NF02kaC5BQypY3Hf8nScd/Iyn4+41SidW6J8xxQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=O2DXBgla8duGYf0eqCj8qNUMlBLUHTKcskq6eKI7anXjsi4CZdQ1JPlJTmJrFWKSc078PfEA1nG/Y3OSGPZd4xrDfWp4Xl4oTxvw8T0Ha9mP2/PEk9E4FqXzYZYdv4Qvh1yB7G6UcsCPmUvfYnPgV/HJ0FyqBFS3tHH8s9pUTjs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=arista.com; spf=pass smtp.mailfrom=arista.com; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b=DGnvXXRu; arc=none smtp.client-ip=209.85.221.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=arista.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arista.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="DGnvXXRu" Received: by mail-wr1-f53.google.com with SMTP id ffacd0b85a97d-33929364bdaso2440301f8f.2 for ; Mon, 29 Jan 2024 19:52:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=google; t=1706586724; x=1707191524; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0Gr9RawEoMTLBvWixWLQ9InE8ituKnBm/PO3iDLKMTs=; b=DGnvXXRuP7fHeGwlHfotvtB7NDR+lSt0QCfkiQoLqF5RVdEjJdv26339kCqSLbQu1C U4ZC/yL7jeEvEfFivqrxG5BE9r6rsQwr4QJ/tlGHXAX6lPZ93LKB0tIQt0bsCRhf1JA9 JSaQA8zevL3rUMaour/Vft5Sc3UCcpJWexai1T+O0D8VRW+eo6deBOw/h3LxvC0KIGRA Z9ID25Xvlzu8vDwp0uTA40vOjBaGeR6tFDubIvEV0wP4EAMd810zlbhDi1VpOvWffO+6 y0x93kJlUUjgVeaJAlV86Tz6yQ0DY3SxbqrIFE8EfGVD1pQSiU+CtRCG8uyeS+LhaPdb PPuw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706586724; x=1707191524; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0Gr9RawEoMTLBvWixWLQ9InE8ituKnBm/PO3iDLKMTs=; b=h0vGcQv3VpHiPcW5BHqF4DzwcIXgueep7CxtuTj4obTBpZRsfQ8bghJpKkMZfEOy7E i1ZGPz7th0e9ZjfIK8QWnLp+Wi9lIC5gWeey14Yj//PGEnYTEgWXpL40pvz8lUs8tWzr G37wxKBTp9TOQq68gg6RGOGWYUuxgMWW/JIZkB7NMjAzkONUNCzM9ch5drwtwYKZU3j3 POYxiGrslc8NkrGuQlfn3PT5IUZ7rK8wKAktRpAFOkOjm+psEa86hIw4EwgcnBvVCACw orTw9FpoYX8aI9typnzuWfjNOiqC9DigOuAjDvgDm+FNzP88TeqwH26ktOTHRUORWG1r qRfQ== X-Gm-Message-State: AOJu0Ywwy/R60JVGXcgfCmRw4F7XWri0EOaAIUoHebFEpPka8OSaWRef Gptn+EwHAwbDmZq4KaFq7mQgLSF+mYqMnBYrBTJEZ/j+aygWgjyqI4sUHN3Gqg== X-Google-Smtp-Source: AGHT+IFyQ4LX2Vm/L7+rQkFA1LfPv+lk7PmRWfGl1yd8VKGXI87EoFvDwGgcnYP/KPnoH9kGWbiYcA== X-Received: by 2002:a5d:6383:0:b0:33a:ed8c:1a6a with SMTP id p3-20020a5d6383000000b0033aed8c1a6amr3210242wru.64.1706586724106; Mon, 29 Jan 2024 19:52:04 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id ay13-20020a5d6f0d000000b00337d6aa3912sm9513207wrb.10.2024.01.29.19.52.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Jan 2024 19:52:03 -0800 (PST) From: Dmitry Safonov To: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Shuah Khan , Dmitry Safonov <0x7f454c46@gmail.com> Cc: Dmitry Safonov , Mohammad Nassiri , Simon Horman , netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/3] selftests/net: Repair RST passive reset selftest Date: Tue, 30 Jan 2024 03:51:54 +0000 Message-ID: <20240130-tcp-ao-test-key-mgmt-v2-3-d190430a6c60@arista.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240130-tcp-ao-test-key-mgmt-v2-0-d190430a6c60@arista.com> References: <20240130-tcp-ao-test-key-mgmt-v2-0-d190430a6c60@arista.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mailer: b4 0.13-dev-b6b4b X-Developer-Signature: v=1; a=ed25519-sha256; t=1706586712; l=10409; i=dima@arista.com; s=20231212; h=from:subject:message-id; bh=DuT4NF02kaC5BQypY3Hf8nScd/Iyn4+41SidW6J8xxQ=; b=hVifgR7SD4AW3xgOjLDaRTI8uyXtdFHKystQvRiDYKg0wi1PLgz3Z0GbL21ICkratszmwTvRa Zp+6bx35hcFA7KVhrfFGvinbcdzCGuxxOKAOBIEy/o2UH2NILXl9eNo X-Developer-Key: i=dima@arista.com; a=ed25519; pk=hXINUhX25b0D/zWBKvd6zkvH7W2rcwh/CH6cjEa3OTk= Currently, the test is racy and seems to not pass anymore. In order to rectify it, aim on TCP_TW_RST. Doesn't seem way too good with this sleep() part, but it seems as a reasonable compromise for the test. There is a plan in-line comment on how-to improve it, going to do it on the top, at this moment I want it to run on netdev/patchwork selftests dashboard. It also slightly changes tcp_ao-lib in order to get SO_ERROR propagated to test_client_verify() return value. Fixes: c6df7b2361d7 ("selftests/net: Add TCP-AO RST test") Signed-off-by: Dmitry Safonov --- tools/testing/selftests/net/tcp_ao/lib/sock.c | 12 ++- tools/testing/selftests/net/tcp_ao/rst.c | 138 +++++++++++++++++--------- 2 files changed, 98 insertions(+), 52 deletions(-) diff --git a/tools/testing/selftests/net/tcp_ao/lib/sock.c b/tools/testing/selftests/net/tcp_ao/lib/sock.c index c75d82885a2e..15aeb0963058 100644 --- a/tools/testing/selftests/net/tcp_ao/lib/sock.c +++ b/tools/testing/selftests/net/tcp_ao/lib/sock.c @@ -62,7 +62,9 @@ int test_wait_fd(int sk, time_t sec, bool write) return -ETIMEDOUT; } - if (getsockopt(sk, SOL_SOCKET, SO_ERROR, &ret, &slen) || ret) + if (getsockopt(sk, SOL_SOCKET, SO_ERROR, &ret, &slen)) + return -errno; + if (ret) return -ret; return 0; } @@ -584,9 +586,11 @@ int test_client_verify(int sk, const size_t msg_len, const size_t nr, { size_t buf_sz = msg_len * nr; char *buf = alloca(buf_sz); + ssize_t ret; randomize_buffer(buf, buf_sz); - if (test_client_loop(sk, buf, buf_sz, msg_len, timeout_sec) != buf_sz) - return -1; - return 0; + ret = test_client_loop(sk, buf, buf_sz, msg_len, timeout_sec); + if (ret < 0) + return (int)ret; + return ret != buf_sz ? -1 : 0; } diff --git a/tools/testing/selftests/net/tcp_ao/rst.c b/tools/testing/selftests/net/tcp_ao/rst.c index ac06009a7f5f..7df8b8700e39 100644 --- a/tools/testing/selftests/net/tcp_ao/rst.c +++ b/tools/testing/selftests/net/tcp_ao/rst.c @@ -1,10 +1,33 @@ // SPDX-License-Identifier: GPL-2.0 -/* Author: Dmitry Safonov */ +/* + * The test checks that both active and passive reset have correct TCP-AO + * signature. An "active" reset (abort) here is procured from closing + * listen() socket with non-accepted connections in the queue: + * inet_csk_listen_stop() => inet_child_forget() => + * => tcp_disconnect() => tcp_send_active_reset() + * + * The passive reset is quite hard to get on established TCP connections. + * It could be procured from non-established states, but the synchronization + * part from userspace in order to reliably get RST seems uneasy. + * So, instead it's procured by corrupting SEQ number on TIMED-WAIT state. + * + * It's important to test both passive and active RST as they go through + * different code-paths: + * - tcp_send_active_reset() makes no-data skb, sends it with tcp_transmit_skb() + * - tcp_v*_send_reset() create their reply skbs and send them with + * ip_send_unicast_reply() + * + * In both cases TCP-AO signatures have to be correct, which is verified by + * (1) checking that the TCP-AO connection was reset and (2) TCP-AO counters. + * + * Author: Dmitry Safonov + */ #include #include "../../../../include/linux/kernel.h" #include "aolib.h" const size_t quota = 1000; +const size_t packet_sz = 100; /* * Backlog == 0 means 1 connection in queue, see: * commit 64a146513f8f ("[NET]: Revert incorrect accept queue...") @@ -59,26 +82,6 @@ static void close_forced(int sk) close(sk); } -static int test_wait_for_exception(int sk, time_t sec) -{ - struct timeval tv = { .tv_sec = sec }; - struct timeval *ptv = NULL; - fd_set efds; - int ret; - - FD_ZERO(&efds); - FD_SET(sk, &efds); - - if (sec) - ptv = &tv; - - errno = 0; - ret = select(sk + 1, NULL, NULL, &efds, ptv); - if (ret < 0) - return -errno; - return ret ? sk : 0; -} - static void test_server_active_rst(unsigned int port) { struct tcp_ao_counters cnt1, cnt2; @@ -155,17 +158,16 @@ static void test_server_passive_rst(unsigned int port) test_fail("server returned %zd", bytes); } - synchronize_threads(); /* 3: chekpoint/restore the connection */ + synchronize_threads(); /* 3: checkpoint the client */ + synchronize_threads(); /* 4: close the server, creating twsk */ if (test_get_tcp_ao_counters(sk, &ao2)) test_error("test_get_tcp_ao_counters()"); - - synchronize_threads(); /* 4: terminate server + send more on client */ - bytes = test_server_run(sk, quota, TEST_RETRANSMIT_SEC); close(sk); + + synchronize_threads(); /* 5: restore the socket, send more data */ test_tcp_ao_counters_cmp("passive RST server", &ao1, &ao2, TEST_CNT_GOOD); - synchronize_threads(); /* 5: verified => closed */ - close(sk); + synchronize_threads(); /* 6: server exits */ } static void *server_fn(void *arg) @@ -284,7 +286,7 @@ static void test_client_active_rst(unsigned int port) test_error("test_wait_fds(): %d", err); synchronize_threads(); /* 3: close listen socket */ - if (test_client_verify(sk[0], 100, quota / 100, TEST_TIMEOUT_SEC)) + if (test_client_verify(sk[0], packet_sz, quota / packet_sz, TEST_TIMEOUT_SEC)) test_fail("Failed to send data on connected socket"); else test_ok("Verified established tcp connection"); @@ -323,7 +325,6 @@ static void test_client_passive_rst(unsigned int port) struct tcp_sock_state img; sockaddr_af saddr; int sk, err; - socklen_t slen = sizeof(err); sk = socket(test_family, SOCK_STREAM, IPPROTO_TCP); if (sk < 0) @@ -337,18 +338,51 @@ static void test_client_passive_rst(unsigned int port) test_error("failed to connect()"); synchronize_threads(); /* 2: accepted => send data */ - if (test_client_verify(sk, 100, quota / 100, TEST_TIMEOUT_SEC)) + if (test_client_verify(sk, packet_sz, quota / packet_sz, TEST_TIMEOUT_SEC)) test_fail("Failed to send data on connected socket"); else test_ok("Verified established tcp connection"); - synchronize_threads(); /* 3: chekpoint/restore the connection */ + synchronize_threads(); /* 3: checkpoint the client */ test_enable_repair(sk); test_sock_checkpoint(sk, &img, &saddr); test_ao_checkpoint(sk, &ao_img); - test_kill_sk(sk); + test_disable_repair(sk); - img.out.seq += quota; + synchronize_threads(); /* 4: close the server, creating twsk */ + + /* + * The "corruption" in SEQ has to be small enough to fit into TCP + * window, see tcp_timewait_state_process() for out-of-window + * segments. + */ + img.out.seq += 5; /* 5 is more noticeable in tcpdump than 1 */ + + /* + * FIXME: This is kind-of ugly and dirty, but it works. + * + * At this moment, the server has close'ed(sk). + * The passive RST that is being targeted here is new data after + * half-duplex close, see tcp_timewait_state_process() => TCP_TW_RST + * + * What is needed here is: + * (1) wait for FIN from the server + * (2) make sure that the ACK from the client went out + * (3) make sure that the ACK was received and processed by the server + * + * Otherwise, the data that will be sent from "repaired" socket + * post SEQ corruption may get to the server before it's in + * TCP_FIN_WAIT2. + * + * (1) is easy with select()/poll() + * (2) is possible by polling tcpi_state from TCP_INFO + * (3) is quite complex: as server's socket was already closed, + * probably the way to do it would be tcp-diag. + */ + sleep(TEST_RETRANSMIT_SEC); + + synchronize_threads(); /* 5: restore the socket, send more data */ + test_kill_sk(sk); sk = socket(test_family, SOCK_STREAM, IPPROTO_TCP); if (sk < 0) @@ -366,25 +400,33 @@ static void test_client_passive_rst(unsigned int port) test_disable_repair(sk); test_sock_state_free(&img); - synchronize_threads(); /* 4: terminate server + send more on client */ - if (test_client_verify(sk, 100, quota / 100, 2 * TEST_TIMEOUT_SEC)) - test_ok("client connection broken post-seq-adjust"); + /* + * This is how "passive reset" is acquired in this test from TCP_TW_RST: + * + * IP 10.0.254.1.7011 > 10.0.1.1.59772: Flags [P.], seq 901:1001, ack 1001, win 249, + * options [tcp-ao keyid 100 rnextkeyid 100 mac 0x10217d6c36a22379086ef3b1], length 100 + * IP 10.0.254.1.7011 > 10.0.1.1.59772: Flags [F.], seq 1001, ack 1001, win 249, + * options [tcp-ao keyid 100 rnextkeyid 100 mac 0x104ffc99b98c10a5298cc268], length 0 + * IP 10.0.1.1.59772 > 10.0.254.1.7011: Flags [.], ack 1002, win 251, + * options [tcp-ao keyid 100 rnextkeyid 100 mac 0xe496dd4f7f5a8a66873c6f93,nop,nop,sack 1 {1001:1002}], length 0 + * IP 10.0.1.1.59772 > 10.0.254.1.7011: Flags [P.], seq 1006:1106, ack 1001, win 251, + * options [tcp-ao keyid 100 rnextkeyid 100 mac 0x1b5f3330fb23fbcd0c77d0ca], length 100 + * IP 10.0.254.1.7011 > 10.0.1.1.59772: Flags [R], seq 3215596252, win 0, + * options [tcp-ao keyid 100 rnextkeyid 100 mac 0x0bcfbbf497bce844312304b2], length 0 + */ + err = test_client_verify(sk, packet_sz, quota / packet_sz, 2 * TEST_TIMEOUT_SEC); + /* Make sure that the connection was reset, not timeouted */ + if (err && err == -ECONNRESET) + test_ok("client sock was passively reset post-seq-adjust"); + else if (err) + test_fail("client sock was not reset post-seq-adjust: %d", err); else - test_fail("client connection still works post-seq-adjust"); - - test_wait_for_exception(sk, TEST_TIMEOUT_SEC); - - if (getsockopt(sk, SOL_SOCKET, SO_ERROR, &err, &slen)) - test_error("getsockopt()"); - if (err != ECONNRESET && err != EPIPE) - test_fail("client connection was not reset: %d", err); - else - test_ok("client connection was reset"); + test_fail("client sock is yet connected post-seq-adjust"); if (test_get_tcp_ao_counters(sk, &ao2)) test_error("test_get_tcp_ao_counters()"); - synchronize_threads(); /* 5: verified => closed */ + synchronize_threads(); /* 6: server exits */ close(sk); test_tcp_ao_counters_cmp("client passive RST", &ao1, &ao2, TEST_CNT_GOOD); } @@ -410,6 +452,6 @@ static void *client_fn(void *arg) int main(int argc, char *argv[]) { - test_init(15, server_fn, client_fn); + test_init(14, server_fn, client_fn); return 0; }