From c437631485a85c3bd034e12f53dd1c8207f05940 Mon Sep 17 00:00:00 2001 From: Andreas Schwab Date: Wed, 19 Jul 2023 09:55:31 +0200 Subject: [PATCH] Restore lookup of IPv4 mapped addresses in files database (bug 25457) This was broken by commit 9c02d0784d ("nss_files: Remove RES_USE_INET6 from hosts processing"), which removed too much. --- nss/Makefile | 1 + nss/nss_files/files-hosts.c | 24 ++++--- nss/tst-nss-files-hosts-v4mapped.c | 41 +++++++++++ .../etc/hosts | 1 + .../etc/nsswitch.conf | 1 + resolv/mapv4v6addr.h | 69 +++++++++++++++++++ 6 files changed, 128 insertions(+), 9 deletions(-) create mode 100644 nss/tst-nss-files-hosts-v4mapped.c create mode 100644 nss/tst-nss-files-hosts-v4mapped.root/etc/hosts create mode 100644 nss/tst-nss-files-hosts-v4mapped.root/etc/nsswitch.conf create mode 100644 resolv/mapv4v6addr.h diff --git a/nss/Makefile b/nss/Makefile index 3a9ea065ac..06fcdc450f 100644 --- a/nss/Makefile +++ b/nss/Makefile @@ -77,6 +77,7 @@ tests-container := \ tst-nss-db-endgrent \ tst-nss-db-endpwent \ tst-nss-files-hosts-long \ + tst-nss-files-hosts-v4mapped \ tst-nss-gai-actions \ tst-nss-test3 \ tst-reload1 \ diff --git a/nss/nss_files/files-hosts.c b/nss/nss_files/files-hosts.c index 05b60fec43..035b7b938f 100644 --- a/nss/nss_files/files-hosts.c +++ b/nss/nss_files/files-hosts.c @@ -27,6 +27,7 @@ #include /* Get implementation for some internal functions. */ +#include "../resolv/mapv4v6addr.h" #include "../resolv/res_hconf.h" @@ -34,8 +35,8 @@ #define DATABASE "hosts" #define NEED_H_ERRNO -#define EXTRA_ARGS , af -#define EXTRA_ARGS_DECL , int af +#define EXTRA_ARGS , af, flags +#define EXTRA_ARGS_DECL , int af, int flags #define ENTDATA hostent_data struct hostent_data @@ -60,8 +61,12 @@ LINE_PARSER af = af == AF_UNSPEC ? AF_INET : af; else { - if (af == AF_INET - && __inet_pton (AF_INET6, addr, entdata->host_addr) > 0) + if (af == AF_INET6 && (flags & AI_V4MAPPED) != 0 + && __inet_pton (AF_INET, addr, entdata->host_addr) > 0) + map_v4v6_address ((char *) entdata->host_addr, + (char *) entdata->host_addr); + else if (af == AF_INET + && __inet_pton (AF_INET6, addr, entdata->host_addr) > 0) { if (IN6_IS_ADDR_V4MAPPED (entdata->host_addr)) memcpy (entdata->host_addr, entdata->host_addr + 12, INADDRSZ); @@ -94,13 +99,14 @@ LINE_PARSER STRING_FIELD (result->h_name, isspace, 1); }) -#define EXTRA_ARGS_VALUE , AF_INET +#define EXTRA_ARGS_VALUE , AF_INET, 0 #include "files-XXX.c" #undef EXTRA_ARGS_VALUE /* We only need to consider IPv4 mapped addresses if the input to the gethostbyaddr() function is an IPv6 address. */ -#define EXTRA_ARGS_VALUE , af +#define EXTRA_ARGS_VALUE \ + , af, (len == IN6ADDRSZ ? AI_V4MAPPED : 0) DB_LOOKUP (hostbyaddr, ,,, { if (result->h_length == (int) len @@ -152,7 +158,7 @@ gethostbyname3_multi (FILE * stream, const char *name, int af, while (true) { status = internal_getent (stream, &tmp_result_buf, tmp_buffer.data, - tmp_buffer.length, errnop, herrnop, af); + tmp_buffer.length, errnop, herrnop, af, 0); /* Enlarge the buffer if necessary. */ if (status == NSS_STATUS_TRYAGAIN && *herrnop == NETDB_INTERNAL && *errnop == ERANGE) @@ -337,7 +343,7 @@ _nss_files_gethostbyname3_r (const char *name, int af, struct hostent *result, if (status == NSS_STATUS_SUCCESS) { while ((status = internal_getent (stream, result, buffer, buflen, errnop, - herrnop, af)) + herrnop, af, 0)) == NSS_STATUS_SUCCESS) { LOOKUP_NAME_CASE (h_name, h_aliases) @@ -402,7 +408,7 @@ _nss_files_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat, struct hostent result; status = internal_getent (stream, &result, buffer, buflen, errnop, - herrnop, AF_UNSPEC); + herrnop, AF_UNSPEC, 0); if (status != NSS_STATUS_SUCCESS) break; diff --git a/nss/tst-nss-files-hosts-v4mapped.c b/nss/tst-nss-files-hosts-v4mapped.c new file mode 100644 index 0000000000..45582904e6 --- /dev/null +++ b/nss/tst-nss-files-hosts-v4mapped.c @@ -0,0 +1,41 @@ +/* Test lookup of IPv4 mapped addresses in files database (bug 25457) + + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; see the file COPYING.LIB. If + not, see . */ + +#include +#include +#include + +static int +do_test (void) +{ + struct sockaddr_in6 s6 = { .sin6_family = AF_INET6 }; + inet_pton (AF_INET6, "::ffff:192.168.0.1", &s6.sin6_addr); + + char node[NI_MAXHOST]; + int res = getnameinfo ((struct sockaddr *) &s6, sizeof (s6), node, + sizeof (node), NULL, 0, NI_NAMEREQD); + if (res) + printf ("%d %s\n", res, gai_strerror (res)); + else + printf ("node=%s\n", node); + + return res != 0; +} + +#include diff --git a/nss/tst-nss-files-hosts-v4mapped.root/etc/hosts b/nss/tst-nss-files-hosts-v4mapped.root/etc/hosts new file mode 100644 index 0000000000..609b25ad39 --- /dev/null +++ b/nss/tst-nss-files-hosts-v4mapped.root/etc/hosts @@ -0,0 +1 @@ +192.168.0.1 v4mapped diff --git a/nss/tst-nss-files-hosts-v4mapped.root/etc/nsswitch.conf b/nss/tst-nss-files-hosts-v4mapped.root/etc/nsswitch.conf new file mode 100644 index 0000000000..5b0c6a4199 --- /dev/null +++ b/nss/tst-nss-files-hosts-v4mapped.root/etc/nsswitch.conf @@ -0,0 +1 @@ +hosts: files diff --git a/resolv/mapv4v6addr.h b/resolv/mapv4v6addr.h new file mode 100644 index 0000000000..7f85f7d5e3 --- /dev/null +++ b/resolv/mapv4v6addr.h @@ -0,0 +1,69 @@ +/* + * ++Copyright++ 1985, 1988, 1993 + * - + * Copyright (c) 1985, 1988, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * - + * Portions Copyright (c) 1993 by Digital Equipment Corporation. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies, and that + * the name of Digital Equipment Corporation not be used in advertising or + * publicity pertaining to distribution of the document or software without + * specific, written prior permission. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL + * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT + * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL + * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR + * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS + * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS + * SOFTWARE. + * - + * --Copyright-- + */ + +#include +#include + +static void +map_v4v6_address (const char *src, char *dst) +{ + u_char *p = (u_char *) dst; + int i; + + /* Move the IPv4 part to the right position. */ + memcpy (dst + 12, src, INADDRSZ); + + /* Mark this ipv6 addr as a mapped ipv4. */ + for (i = 0; i < 10; i++) + *p++ = 0x00; + *p++ = 0xff; + *p = 0xff; +} -- 2.43.5