From patchwork Fri Aug 26 10:33:19 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 57084 X-Patchwork-Delegate: siddhesh@gotplt.org Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CDC33384D176 for ; Fri, 26 Aug 2022 10:35:21 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CDC33384D176 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1661510121; bh=681Tns9XZwZ7358PkDP3fV9hcQdX/A1q+adZVA9FX3c=; h=To:Subject:In-Reply-To:References:Date:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=hDPKlOy4MoALRb/IKpAvI5w+5gsflShlvqD4ZuKaoClKKrtJKzHmzLzprkPxaF3io Dr1sRJ/cJ1ZECQHgF4Xb+FZKuLVQXHc55oHzhgyeFR8RqldKtP20tQY1gtNXvSBFYv AYBLT8vY9i8e1S/RDljFWWQT0B/uAgUHPHw/5oCY= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id D43063837687 for ; Fri, 26 Aug 2022 10:33:23 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D43063837687 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-344-WaCI_7rnPTGNS3dyI-se0A-1; Fri, 26 Aug 2022 06:33:22 -0400 X-MC-Unique: WaCI_7rnPTGNS3dyI-se0A-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2EFB585A585 for ; Fri, 26 Aug 2022 10:33:22 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.82]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 236ED18EA8 for ; Fri, 26 Aug 2022 10:33:20 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH v2 01/13] resolv: Add tst-resolv-byaddr for testing reverse lookup In-Reply-To: References: X-From-Line: 1e53a7e6cd3fdeb9410581dc064c7d6d8b16186c Mon Sep 17 00:00:00 2001 Message-Id: <1e53a7e6cd3fdeb9410581dc064c7d6d8b16186c.1661509943.git.fweimer@redhat.com> Date: Fri, 26 Aug 2022 12:33:19 +0200 User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-9.6 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, MANY_SUBDOM, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Reviewed-by: Siddhesh Poyarekar Reviewed-by: Siddhesh Poyarekar --- resolv/Makefile | 2 + resolv/tst-resolv-byaddr.c | 326 +++++++++++++++++++++++++++ resolv/tst-resolv-maybe_insert_sig.h | 32 +++ 3 files changed, 360 insertions(+) create mode 100644 resolv/tst-resolv-byaddr.c create mode 100644 resolv/tst-resolv-maybe_insert_sig.h diff --git a/resolv/Makefile b/resolv/Makefile index 5b15321f9b..98b10d97a0 100644 --- a/resolv/Makefile +++ b/resolv/Makefile @@ -91,6 +91,7 @@ tests += \ tst-res_hnok \ tst-resolv-basic \ tst-resolv-binary \ + tst-resolv-byaddr \ tst-resolv-edns \ tst-resolv-network \ tst-resolv-noaaaa \ @@ -260,6 +261,7 @@ $(objpfx)tst-resolv-ai_idn-nolibidn2.out: \ $(gen-locales) $(objpfx)tst-no-libidn2.so $(objpfx)tst-resolv-basic: $(objpfx)libresolv.so $(shared-thread-library) $(objpfx)tst-resolv-binary: $(objpfx)libresolv.so $(shared-thread-library) +$(objpfx)tst-resolv-byaddr: $(objpfx)libresolv.so $(shared-thread-library) $(objpfx)tst-resolv-edns: $(objpfx)libresolv.so $(shared-thread-library) $(objpfx)tst-resolv-network: $(objpfx)libresolv.so $(shared-thread-library) $(objpfx)tst-resolv-res_init: $(objpfx)libresolv.so diff --git a/resolv/tst-resolv-byaddr.c b/resolv/tst-resolv-byaddr.c new file mode 100644 index 0000000000..6299e89837 --- /dev/null +++ b/resolv/tst-resolv-byaddr.c @@ -0,0 +1,326 @@ +/* Test reverse DNS lookup. + Copyright (C) 2022 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; if not, see + . */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "tst-resolv-maybe_insert_sig.h" + +/* QNAME format: + + ADDRESSES.CNAMES...(lots of 0s)...8.b.d.0.1.0.0.2.ip6.arpa. + CNAMES|ADDRESSES.2.0.192.in-addr-arpa. + + For the IPv4 reverse lookup, the address count is in the lower + bits. + + CNAMES is the length of the CNAME chain, ADDRESSES is the number of + addresses in the response. The special value 15 means that there + are no addresses, and the RCODE is NXDOMAIN. */ +static void +response (const struct resolv_response_context *ctx, + struct resolv_response_builder *b, + const char *qname, uint16_t qclass, uint16_t qtype) +{ + TEST_COMPARE (qclass, C_IN); + TEST_COMPARE (qtype, T_PTR); + + unsigned int addresses, cnames, bits; + char *tail; + if (strstr (qname, "ip6.arpa") != NULL + && sscanf (qname, "%x.%x.%ms", &addresses, &cnames, &tail) == 3) + TEST_COMPARE_STRING (tail, "\ +0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa"); + else if (sscanf (qname, "%u.%ms", &bits, &tail) == 2) + { + TEST_COMPARE_STRING (tail, "2.0.192.in-addr.arpa"); + addresses = bits & 0x0f; + cnames = bits >> 4; + } + else + FAIL_EXIT1 ("invalid QNAME: %s", qname); + free (tail); + + int rcode; + if (addresses == 15) + { + /* Special case: Use no addresses with NXDOMAIN response. */ + rcode = ns_r_nxdomain; + addresses = 0; + } + else + rcode = 0; + + struct resolv_response_flags flags = { .rcode = rcode }; + resolv_response_init (b, flags); + resolv_response_add_question (b, qname, qclass, qtype); + resolv_response_section (b, ns_s_an); + maybe_insert_sig (b, qname); + + /* Provide the requested number of CNAME records. */ + char *previous_name = (char *) qname; + for (int unique = 0; unique < cnames; ++unique) + { + resolv_response_open_record (b, previous_name, qclass, T_CNAME, 60); + char *new_name = xasprintf ("%d.alias.example", unique); + resolv_response_add_name (b, new_name); + resolv_response_close_record (b); + + maybe_insert_sig (b, qname); + + if (previous_name != qname) + free (previous_name); + previous_name = new_name; + } + + for (int unique = 0; unique < addresses; ++unique) + { + resolv_response_open_record (b, previous_name, qclass, T_PTR, 60); + char *ptr = xasprintf ("unique-%d.cnames-%u.addresses-%u.example", + unique, cnames, addresses); + resolv_response_add_name (b, ptr); + free (ptr); + resolv_response_close_record (b); + } + + if (previous_name != qname) + free (previous_name); +} + +/* Used to check that gethostbyaddr_r does not write past the buffer + end. */ +static struct support_next_to_fault ntf; + +/* Perform a gethostbyaddr call and check the result. */ +static void +check_gethostbyaddr (const char *address, const char *expected) +{ + unsigned char bytes[16]; + unsigned int byteslen; + int family; + if (strchr (address, ':') != NULL) + { + family = AF_INET6; + byteslen = 16; + } + else + { + family = AF_INET; + byteslen = 4; + } + TEST_COMPARE (inet_pton (family, address, bytes), 1); + + struct hostent *e = gethostbyaddr (bytes, byteslen, family); + check_hostent (address, e, expected); + + if (e == NULL) + return; + + /* Try gethostbyaddr_r with increasing sizes until success. First + compute a reasonable minimum buffer size, to avoid many pointless + attempts. */ + size_t minimum_size = strlen (e->h_name); + for (int i = 0; e->h_addr_list[i] != NULL; ++i) + minimum_size += e->h_length + sizeof (char *); + for (int i = 0; e->h_aliases[i] != NULL; ++i) + minimum_size += strlen (e->h_aliases[i]) + 1 + sizeof (char *); + + /* Gradually increase the size until success. */ + for (size_t size = minimum_size; size < ntf.length; ++size) + { + struct hostent result; + int herrno; + int ret = gethostbyaddr_r (bytes, byteslen, family, &result, + ntf.buffer + ntf.length - size, size, + &e, &herrno); + if (ret == ERANGE) + /* Retry with larger size. */ + TEST_COMPARE (herrno, NETDB_INTERNAL); + else if (ret == 0) + { + TEST_VERIFY (size > minimum_size); + check_hostent (address, e, expected); + return; + } + else + FAIL_EXIT1 ("Unexpected gethostbyaddr_r failure: %d", ret); + } + + FAIL_EXIT1 ("gethostbyaddr_r always failed for: %s", address); +} + +/* Perform a getnameinfo call and check the result. */ +static void +check_getnameinfo (const char *address, const char *expected) +{ + struct sockaddr_in sin = { }; + struct sockaddr_in6 sin6 = { }; + void *sa; + socklen_t salen; + if (strchr (address, ':') != NULL) + { + sin6.sin6_family = AF_INET6; + TEST_COMPARE (inet_pton (AF_INET6, address, &sin6.sin6_addr), 1); + sin6.sin6_port = htons (80); + sa = &sin6; + salen = sizeof (sin6); + } + else + { + sin.sin_family = AF_INET; + TEST_COMPARE (inet_pton (AF_INET, address, &sin.sin_addr), 1); + sin.sin_port = htons (80); + sa = &sin; + salen = sizeof (sin); + } + + char host[64]; + char service[64]; + int ret = getnameinfo (sa, salen, host, + sizeof (host), service, sizeof (service), + NI_NAMEREQD | NI_NUMERICSERV); + switch (ret) + { + case 0: + TEST_COMPARE_STRING (host, expected); + TEST_COMPARE_STRING (service, "80"); + break; + case EAI_SYSTEM: + TEST_COMPARE_STRING (strerror (errno), expected); + break; + default: + TEST_COMPARE_STRING (gai_strerror (ret), expected); + } +} + +static int +do_test (void) +{ + /* Some reasonably upper bound for the maximum response size. */ + ntf = support_next_to_fault_allocate (4096); + + struct resolv_test *obj = resolv_test_start + ((struct resolv_redirect_config) + { + .response_callback = response + }); + + for (int do_insert_sig = 0; do_insert_sig < 2; ++do_insert_sig) + { + insert_sig = do_insert_sig; + + /* No PTR record, RCODE=0. */ + check_gethostbyaddr ("192.0.2.0", "error: NO_RECOVERY\n"); + check_getnameinfo ("192.0.2.0", "Name or service not known"); + check_gethostbyaddr ("192.0.2.16", "error: NO_RECOVERY\n"); + check_getnameinfo ("192.0.2.16", "Name or service not known"); + check_gethostbyaddr ("192.0.2.32", "error: NO_RECOVERY\n"); + check_getnameinfo ("192.0.2.32", "Name or service not known"); + check_gethostbyaddr ("2001:db8::", "error: NO_RECOVERY\n"); + check_getnameinfo ("2001:db8::", "Name or service not known"); + check_gethostbyaddr ("2001:db8::10", "error: NO_RECOVERY\n"); + check_getnameinfo ("2001:db8::10", "Name or service not known"); + check_gethostbyaddr ("2001:db8::20", "error: NO_RECOVERY\n"); + check_getnameinfo ("2001:db8::20", "Name or service not known"); + + /* No PTR record, NXDOMAIN. */ + check_gethostbyaddr ("192.0.2.15", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("192.0.2.15", "Name or service not known"); + check_gethostbyaddr ("192.0.2.31", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("192.0.2.31", "Name or service not known"); + check_gethostbyaddr ("192.0.2.47", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("192.0.2.47", "Name or service not known"); + check_gethostbyaddr ("2001:db8::f", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("2001:db8::f", "Name or service not known"); + check_gethostbyaddr ("2001:db8::1f", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("2001:db8::1f", "Name or service not known"); + check_gethostbyaddr ("2001:db8::2f", "error: HOST_NOT_FOUND\n"); + check_getnameinfo ("2001:db8::2f", "Name or service not known"); + + /* Actual response data. Only the first PTR record is returned. */ + check_gethostbyaddr ("192.0.2.1", + "name: unique-0.cnames-0.addresses-1.example\n" + "address: 192.0.2.1\n"); + check_getnameinfo ("192.0.2.1", + "unique-0.cnames-0.addresses-1.example"); + check_gethostbyaddr ("192.0.2.17", + "name: unique-0.cnames-1.addresses-1.example\n" + "address: 192.0.2.17\n"); + check_getnameinfo ("192.0.2.17", + "unique-0.cnames-1.addresses-1.example"); + check_gethostbyaddr ("192.0.2.18", + "name: unique-0.cnames-1.addresses-2.example\n" + "address: 192.0.2.18\n"); + check_getnameinfo ("192.0.2.18", + "unique-0.cnames-1.addresses-2.example"); + check_gethostbyaddr ("192.0.2.33", + "name: unique-0.cnames-2.addresses-1.example\n" + "address: 192.0.2.33\n"); + check_getnameinfo ("192.0.2.33", + "unique-0.cnames-2.addresses-1.example"); + check_gethostbyaddr ("192.0.2.34", + "name: unique-0.cnames-2.addresses-2.example\n" + "address: 192.0.2.34\n"); + check_getnameinfo ("192.0.2.34", + "unique-0.cnames-2.addresses-2.example"); + + /* Same for IPv6 addresses. */ + check_gethostbyaddr ("2001:db8::1", + "name: unique-0.cnames-0.addresses-1.example\n" + "address: 2001:db8::1\n"); + check_getnameinfo ("2001:db8::1", + "unique-0.cnames-0.addresses-1.example"); + check_gethostbyaddr ("2001:db8::11", + "name: unique-0.cnames-1.addresses-1.example\n" + "address: 2001:db8::11\n"); + check_getnameinfo ("2001:db8::11", + "unique-0.cnames-1.addresses-1.example"); + check_gethostbyaddr ("2001:db8::12", + "name: unique-0.cnames-1.addresses-2.example\n" + "address: 2001:db8::12\n"); + check_getnameinfo ("2001:db8::12", + "unique-0.cnames-1.addresses-2.example"); + check_gethostbyaddr ("2001:db8::21", + "name: unique-0.cnames-2.addresses-1.example\n" + "address: 2001:db8::21\n"); + check_getnameinfo ("2001:db8::21", + "unique-0.cnames-2.addresses-1.example"); + check_gethostbyaddr ("2001:db8::22", + "name: unique-0.cnames-2.addresses-2.example\n" + "address: 2001:db8::22\n"); + check_getnameinfo ("2001:db8::22", + "unique-0.cnames-2.addresses-2.example"); + } + + resolv_test_end (obj); + + support_next_to_fault_free (&ntf); + return 0; +} + +#include diff --git a/resolv/tst-resolv-maybe_insert_sig.h b/resolv/tst-resolv-maybe_insert_sig.h new file mode 100644 index 0000000000..05725225af --- /dev/null +++ b/resolv/tst-resolv-maybe_insert_sig.h @@ -0,0 +1,32 @@ +/* Code snippet for optionally inserting ignored SIG records in resolver tests. + Copyright (C) 2022 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; if not, see + . */ + +/* Set to true for an alternative pass that inserts (ignored) SIG + records. This does not alter the response, so this property is not + encoded in the QNAME. The variable needs to be volatile because + leaf attributes tell GCC that the response function is not + called. */ +static volatile bool insert_sig; + +static void +maybe_insert_sig (struct resolv_response_builder *b, const char *owner) +{ + resolv_response_open_record (b, owner, C_IN, T_SIG, 60); + resolv_response_add_data (b, "", 1); + resolv_response_close_record (b); +}