From owner-freebsd-hackers@freebsd.org Thu Apr 22 10:33:41 2021 Return-Path: Delivered-To: freebsd-hackers@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D636C5EA09E for ; Thu, 22 Apr 2021 10:33:41 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4FQv0P00wrz3hNW; Thu, 22 Apr 2021 10:33:40 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.16.1/8.16.1) with ESMTPS id 13MAXXXm008777 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 22 Apr 2021 13:33:36 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua 13MAXXXm008777 Received: (from kostik@localhost) by tom.home (8.16.1/8.16.1/Submit) id 13MAXXZD008776; Thu, 22 Apr 2021 13:33:33 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 22 Apr 2021 13:33:33 +0300 From: Konstantin Belousov To: Gleb Popov Cc: Mark Millard , freebsd-hackers Subject: Re: A bug with getsockopt(SOL_LOCAL, LOCAL_PEERCRED) ? Message-ID: References: <40116716-D8D9-438D-A168-B26A112D199E@yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on tom.home X-Rspamd-Queue-Id: 4FQv0P00wrz3hNW X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=gmail.com (policy=none); spf=softfail (mx1.freebsd.org: 2001:470:d5e7:1::1 is neither permitted nor denied by domain of kostikbel@gmail.com) smtp.mailfrom=kostikbel@gmail.com X-Spamd-Result: default: False [-0.54 / 15.00]; SUBJECT_ENDS_QUESTION(1.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; DMARC_POLICY_SOFTFAIL(0.10)[gmail.com : No valid SPF, No valid DKIM,none]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FREEMAIL_FROM(0.00)[gmail.com]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; HAS_XAW(0.00)[]; ARC_NA(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all]; NEURAL_SPAM_MEDIUM(0.32)[0.323]; SPAMHAUS_ZRD(0.00)[2001:470:d5e7:1::1:from:127.0.2.255]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; NEURAL_HAM_SHORT(-0.87)[-0.868]; RBL_DBL_DONT_QUERY_IPS(0.00)[2001:470:d5e7:1::1:from]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US]; FREEMAIL_CC(0.00)[yahoo.com,freebsd.org]; MAILMAN_DEST(0.00)[freebsd-hackers]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Technical discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 Apr 2021 10:33:41 -0000 On Thu, Apr 22, 2021 at 07:54:26AM +0300, Gleb Popov wrote: > On Thu, Apr 22, 2021 at 1:00 AM Mark Millard wrote: > > > > > On 2021-Apr-21, at 11:27, Gleb Popov wrote: > > > > > > This makes sense, thanks. > > > > > > However, this code works on Linux and seems to return credentials of the > > user that started the process. I actually stumbled upon this when porting > > this code: > > https://github.com/CollaboraOnline/online/blob/master/net/Socket.cpp#L805 > > > > > > Would it make sense if FreeBSD followed Linux semantics in this case? If > > not, what are my options for porting the software? > > > > From what I can tell . . . > > > > FreeBSD defines LOCAL_PEERCRED and what goes with its use, not linux. > > Linux defines SO_PEERCRED and what goes with its use, not FreeBSD. > > > > If I understand right, your code is incompatible with the referenced > > CollaboraOnline code from just after the #else (so __FreeBSD__ case, > > not the linux case): > > > > getsockopt(getFD(), 0, LOCAL_PEERCRED, &creds, &credSize) > > vs. your: > > getsockopt(s, SOL_LOCAL, LOCAL_PEERCRED, &creds, &credSize) > > > > Note the 0 vs. the SOL_LOCAL. Your code is a mix of Linux > > and FreeBSD code when it should not be. > > > > SOL_LOCAL is defined to 0, so this is fine. > > > > See also the following that involved replacing a SOL_LOCAL > > with a 0 for getsockopt used with LOCAL_PEERCRED: > > > > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=234722 > > > > > Yes, I'm aware that Linux SO_PEERCRED operates on socket level, while ours > operates on level 0. This is taken in account > in the code I posted. > > As I said, the error stems from the fact that Linux allows getting creds > from the listening socket. There is no peer for listening socket. Show minimal code that works for you on Linux.