From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Leo Prikler Newsgroups: gmane.lisp.guile.devel Subject: [PATCH] Allow null bytes in UNIX sockets. Date: Mon, 29 Mar 2021 17:37:58 +0200 Message-ID: <20210329153757.16476-1-leo.priker@student.tugraz.at> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="34350"; mail-complaints-to="usenet@ciao.gmane.io" To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane-mx.org@gnu.org Mon Mar 29 21:15:19 2021 Return-path: Envelope-to: guile-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lQxM6-0008la-D7 for guile-devel@m.gmane-mx.org; Mon, 29 Mar 2021 21:15:18 +0200 Original-Received: from localhost ([::1]:39108 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lQxM4-0002ur-Tw for guile-devel@m.gmane-mx.org; Mon, 29 Mar 2021 15:15:17 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:33030) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lQu54-0004Zr-AV for guile-devel@gnu.org; Mon, 29 Mar 2021 11:45:31 -0400 Original-Received: from mailrelay.tugraz.at ([129.27.2.202]:57845) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lQu4u-0008CG-J8 for guile-devel@gnu.org; Mon, 29 Mar 2021 11:45:29 -0400 Original-Received: from localhost.localdomain (194-96-13-79.adsl.highway.telekom.at [194.96.13.79]) by mailrelay.tugraz.at (Postfix) with ESMTPSA id 4F8GvJ0kP7z3yWJ for ; Mon, 29 Mar 2021 17:38:35 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tugraz.at; s=mailrelay; t=1617032316; bh=xyaK/z3uYIYf6jfxyl7ovAj5eyreb8Lyu3PzwNtzHfk=; h=From:To:Subject:Date; b=kHAbtrlwqpyza1yQFAKEty8R+It2Hjw1Nu233C4mX4vR0pEQa+YtETjvrmK6D43iU Baqv4qR+xKBCsg4EWbJPVsDfbFBRErosj5WfgvuV04PdQJ79/cEr9D9dWR/oGOnf/F NLSrN3KW9SMSe+D2XMW1/Gqs2nizxJb6odiI1w/s= X-Mailer: git-send-email 2.31.0 X-TUG-Backscatter-control: bt4lQm5Tva3SBgCuw0EnZw X-Scanned-By: MIMEDefang 2.74 on 129.27.10.117 Received-SPF: pass client-ip=129.27.2.202; envelope-from=leo.priker@student.tugraz.at; helo=mailrelay.tugraz.at X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Mon, 29 Mar 2021 15:14:54 -0400 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane-mx.org@gnu.org Original-Sender: "guile-devel" Xref: news.gmane.io gmane.lisp.guile.devel:20717 Archived-At: The current socket address constructors all assume, that there are no null bytes in the socket path. This assumption does not hold in Linux, which uses an initial null byte to demarcate abstract sockets and ignores all further null bytes [1]. [1] https://www.man7.org/linux/man-pages/man7/unix.7.html * libguile/sockets.c (scm_fill_sockaddr)[HAVE_UNIX_DOMAIN_SOCKETS]: Use scm_to_locale_stringn to construct c_address. Use memcpy instead of strcpy and calculate size directly instead of using SUN_LEN. (_scm_from_sockaddr): Copy the entire path up to the limits imposed by addr_size. * test-suite/tests/00-socket.test: ("make-socket-address"): Add case for abstract unix sockets. ("AF_UNIX/SOCK_STREAM"): Add abstract socket versions of bind, listen, connect and accept. --- libguile/socket.c | 18 +++++--- test-suite/tests/00-socket.test | 78 +++++++++++++++++++++++++++++++-- 2 files changed, 86 insertions(+), 10 deletions(-) diff --git a/libguile/socket.c b/libguile/socket.c index 9b87c0c14..ffb3de8a1 100644 --- a/libguile/socket.c +++ b/libguile/socket.c @@ -804,10 +804,11 @@ scm_fill_sockaddr (int fam, SCM address, SCM *args, int which_arg, struct sockaddr_un *soka; int addr_size; char *c_address; + size_t c_address_size; scm_dynwind_begin (0); - c_address = scm_to_locale_string (address); + c_address = scm_to_locale_stringn (address, &c_address_size); scm_dynwind_free (c_address); /* the static buffer size in sockaddr_un seems to be arbitrary @@ -817,12 +818,14 @@ scm_fill_sockaddr (int fam, SCM address, SCM *args, int which_arg, connect/bind etc., to fail. sun_path is always the last member of the structure. */ addr_size = sizeof (struct sockaddr_un) - + MAX (0, strlen (c_address) + 1 - (sizeof soka->sun_path)); + + MAX (0, c_address_size + 1 - (sizeof soka->sun_path)); soka = (struct sockaddr_un *) scm_malloc (addr_size); - memset (soka, 0, addr_size); /* for sun_len: see sin_len above. */ + memset (soka, 0, addr_size); soka->sun_family = AF_UNIX; - strcpy (soka->sun_path, c_address); - *size = SUN_LEN (soka); + /* we accept 0-bytes here (used for abstract sockets in Linux); + therefore do not use strlen() or SUN_LEN! */ + memcpy (soka->sun_path, c_address, c_address_size); + *size = offsetof (struct sockaddr_un, sun_path) + c_address_size; scm_dynwind_end (); return (struct sockaddr *) soka; @@ -1036,7 +1039,10 @@ _scm_from_sockaddr (const scm_t_max_sockaddr *address, unsigned addr_size, if (addr_size <= offsetof (struct sockaddr_un, sun_path)) SCM_SIMPLE_VECTOR_SET(result, 1, SCM_BOOL_F); else - SCM_SIMPLE_VECTOR_SET(result, 1, scm_from_locale_string (nad->sun_path)); + { + size_t path_size = addr_size - offsetof (struct sockaddr_un, sun_path); + SCM_SIMPLE_VECTOR_SET(result, 1, scm_from_locale_stringn(nad->sun_path, path_size)); + } } break; #endif diff --git a/test-suite/tests/00-socket.test b/test-suite/tests/00-socket.test index 027bd8519..5196b4b7d 100644 --- a/test-suite/tests/00-socket.test +++ b/test-suite/tests/00-socket.test @@ -128,10 +128,15 @@ (= (sockaddr:flowinfo sa*) 1))))) (if (defined? 'AF_UNIX) - (pass-if "AF_UNIX" - (let ((sa (make-socket-address AF_UNIX "/tmp/unix-socket"))) - (and (= (sockaddr:fam sa) AF_UNIX) - (string=? (sockaddr:path sa) "/tmp/unix-socket")))))) + (begin + (pass-if "AF_UNIX" + (let ((sa (make-socket-address AF_UNIX "/tmp/unix-socket"))) + (and (= (sockaddr:fam sa) AF_UNIX) + (string=? (sockaddr:path sa) "/tmp/unix-socket")))) + (pass-if "AF_UNIX abstract" + (let ((sa (make-socket-address AF_UNIX "\x00/tmp/abstract-socket"))) + (and (= (sockaddr:fam sa) AF_UNIX) + (string=? (sockaddr:path sa) "\x00/tmp/abstract-socket"))))))) ;;; ;;; setsockopt @@ -319,6 +324,71 @@ #t) + ;; testing `bind', `listen' and `connect' on abstract stream-oriented sockets + + (let ((server-socket (socket AF_UNIX SOCK_STREAM 0)) + (server-bound? #f) + (server-listening? #f) + (server-pid #f) + (path (temp-file-path))) + + (false-if-exception (delete-file path)) + (set! path (string-append "\x00" path)) + + (pass-if "bind abstract" + (catch 'system-error + (lambda () + (bind server-socket AF_UNIX path) + (set! server-bound? #t) + #t) + (lambda args + (let ((errno (system-error-errno args))) + (cond ((= errno EADDRINUSE) (throw 'unresolved)) + (else (apply throw args))))))) + + (pass-if "listen abstract" + (if (not server-bound?) + (throw 'unresolved) + (begin + (listen server-socket 123) + (set! server-listening? #t) + #t))) + + (force-output (current-output-port)) + (force-output (current-error-port)) + (when server-listening? + (let ((pid (primitive-fork-if-available))) + ;; Spawn a server process. + (case pid + ((-1) ;; fork not available + #f) + ((0) ;; the kid: serve one connection and exit + (let serve ((conn + (false-if-exception (accept server-socket))) + (count 0)) + (if (not conn) + (exit 1) + (exit 0)))) + (else ;; the parent + (set! server-pid pid) + #t)))) + + (pass-if "connect abstract" + (if (not server-pid) + (throw 'unresolved) + (let ((s (socket AF_UNIX SOCK_STREAM 0))) + (display "connect abstract\n") + (connect s AF_UNIX path) + #t))) + + (pass-if "accept abstract" + (if (not server-pid) + (throw 'unresolved) + (begin + (let ((status (cdr (waitpid server-pid)))) + (eqv? 0 (status:exit-val status)))))) + + #t) ;; Testing `send', `recv!' & co. on stream-oriented sockets (with ;; a bit of duplication with the above.) -- 2.31.0