From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 105306 invoked by alias); 30 Jan 2020 16:28:11 -0000 Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Received: (qmail 105211 invoked by uid 89); 30 Jan 2020 16:28:10 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,KAM_NUMSUBJECT,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.1 spammy=foremost, MAC, password, Connection X-HELO: mout.gmx.com Received: from mout.gmx.com (HELO mout.gmx.com) (74.208.4.200) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 30 Jan 2020 16:28:08 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mail.com; s=dbd5af2cbaf7; t=1580401686; bh=aeXCsJCtf3D6mFnXxW2N+2fNnag7vKptUMSrO0CV+YI=; h=X-UI-Sender-Class:From:Date:Subject:To; b=7LFNdmUZ6/5k4mt8ZFjnJGi8xFLC913CNkAvKfGjMk5JFOHkClyxEzx999Z1+8kCY GJhfF0dp3CUZycs0yDErwqC/rxv37qFP94naYRuq4N+bUv0/TVTlfwaxrbbekjtS5m CNq9w2fwB+MzgLDy4kB0xydqGWgKvf0Jj7y6DnAs= X-UI-Sender-Class: 214d933f-fd2f-45c7-a636-f5d79ae31a79 Received: from mail-lj1-f170.google.com ([209.85.208.170]) by mail.gmx.com (mrgmxus001 [74.208.5.15]) with ESMTPSA (Nemesis) id 0MD9ZK-1inMNd2KCK-00GYuS for ; Thu, 30 Jan 2020 17:28:05 +0100 Received: by mail-lj1-f170.google.com with SMTP id w1so4042627ljh.5 for ; Thu, 30 Jan 2020 08:28:03 -0800 (PST) MIME-Version: 1.0 From: Bill Stewart Date: Thu, 30 Jan 2020 16:28:00 -0000 Message-ID: Subject: sshd sessions hang after cygwin1.dll 3.0.7 To: cygwin@cygwin.com Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2020-01/txt/msg00311.txt.bz2 I have created an OpenSSH installer for Windows users: https://github.com/Bill-Stewart/Cygwin-OpenSSH Basically it includes only the minimum files from Cygwin needed to run OpenSSH and has some additional conveniences (the foremost of which is to automatically install the service). The problem: When I use cygwin1.dll versions newer than 3.0.7, sshd.exe hangs whenever establishing a connection. Following is the output from 'sshd -d': debug1: sshd version OpenSSH_8.1, OpenSSL 1.1.1d 10 Sep 2019 debug1: private host key #0: ssh-rsa SHA256:... debug1: private host key #1: ecdsa-sha2-nistp256 SHA256:... debug1: private host key #2: ssh-ed25519 SHA256:... debug1: rexec_argv[0]='/usr/sbin/sshd' debug1: rexec_argv[1]='-d' debug1: Bind to port 22 on ::. Server listening on :: port 22. debug1: Bind to port 22 on 0.0.0.0. Server listening on 0.0.0.0 port 22. debug1: fd 5 clearing O_NONBLOCK debug1: Server will not fork when running in debugging mode. debug1: rexec start in 5 out 5 newsock 5 pipe -1 sock 8 debug1: inetd sockets after dupping: 4, 4 Connection from port 52466 on port 22 debug1: Local version string SSH-2.0-OpenSSH_8.1 debug1: Remote protocol version 2.0, remote software version OpenSSH_8.0 debug1: match: OpenSSH_8.0 pat OpenSSH* compat 0x04000000 debug1: permanently_set_uid: 197767/197121 [preauth] debug1: list_hostkey_types: rsa-sha2-512,rsa-sha2-256,ssh-rsa,ecdsa-sha2-nistp256,ssh-ed25519 [preauth] debug1: SSH2_MSG_KEXINIT sent [preauth] debug1: SSH2_MSG_KEXINIT received [preauth] debug1: kex: algorithm: curve25519-sha256 [preauth] debug1: kex: host key algorithm: ecdsa-sha2-nistp256 [preauth] debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: compression: none [preauth] debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: compression: none [preauth] debug1: expecting SSH2_MSG_KEX_ECDH_INIT [preauth] debug1: rekey out after 134217728 blocks [preauth] debug1: SSH2_MSG_NEWKEYS sent [preauth] debug1: Sending SSH2_MSG_EXT_INFO [preauth] debug1: expecting SSH2_MSG_NEWKEYS [preauth] debug1: SSH2_MSG_NEWKEYS received [preauth] debug1: rekey in after 134217728 blocks [preauth] debug1: KEX done [preauth] debug1: userauth-request for user service ssh-connection method none [preauth] debug1: attempt 0 failures 0 [preauth] debug1: user matched 'User ' at line 142 debug1: authentication methods list 0: password debug1: userauth_send_banner: sent [preauth] debug1: authentication methods list 0: password [preauth] debug1: userauth-request for user service ssh-connection method password [preauth] debug1: attempt 1 failures 0 [preauth] Accepted password for from port 52466 ssh2 debug1: monitor_child_preauth: has been authenticated by privileged process debug1: monitor_read_log: child log fd closed debug1: rekey in after 134217728 blocks debug1: rekey out after 134217728 blocks debug1: ssh_packet_set_postauth: called debug1: active: key options: agent-forwarding port-forwarding pty user-rc x11-forwarding debug1: Entering interactive session for SSH2. debug1: server_init_dispatch debug1: server_input_channel_open: ctype session rchan 0 win 1048576 max 16384 debug1: input_session_request debug1: channel 0: new [server-session] debug1: session_new: session 0 debug1: session_open: channel 0 debug1: session_open: session 0: link with channel 0 debug1: server_input_channel_open: confirm session debug1: server_input_global_request: rtype no-more-sessions@openssh.com want_reply 0 debug1: server_input_channel_req: channel 0 request pty-req reply 1 debug1: session_by_channel: session 0 channel 0 debug1: session_input_channel_req: session 0 req pty-req debug1: Allocating pty. The only resolution is to forcibly terminate the spawned copy of sshd (the one spawned by the 'sshd -d' process). Server is running Windows 10 v1909. I have tested, and the hang occurs in all versions of cygwin1.dll after 3.0.7. When I revert back to cygwin1.dll 3.0.7, the problem does not occur, and the connection succeeds. Any ideas? Thanks! Bill -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple