You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 

449 lines
13 KiB

commit 480c820493add16e8dda6f3189d834223e1f4f39
Author: Florian Weimer <fweimer@redhat.com>
Date: Tue Aug 30 10:02:49 2022 +0200
resolv: Add new tst-resolv-invalid-cname
This test checks resolution through CNAME chains that do not contain
host names (bug 12154).
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 9caf782276ecea4bc86fc94fbb52779736f3106d)
Conflicts:
resolv/Makefile
(usual test differences)
diff --git a/resolv/Makefile b/resolv/Makefile
index fded244d61068060..ea1518ec2da860c1 100644
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -99,6 +99,7 @@ tests += \
tst-resolv-binary \
tst-resolv-byaddr \
tst-resolv-edns \
+ tst-resolv-invalid-cname \
tst-resolv-network \
tst-resolv-noaaaa \
tst-resolv-nondecimal \
@@ -279,6 +280,8 @@ $(objpfx)tst-resolv-res_init-multi: $(objpfx)libresolv.so \
$(objpfx)tst-resolv-res_init-thread: $(objpfx)libresolv.so \
$(shared-thread-library)
$(objpfx)tst-resolv-noaaaa: $(objpfx)libresolv.so $(shared-thread-library)
+$(objpfx)tst-resolv-invalid-cname: $(objpfx)libresolv.so \
+ $(shared-thread-library)
$(objpfx)tst-resolv-nondecimal: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-qtypes: $(objpfx)libresolv.so $(shared-thread-library)
$(objpfx)tst-resolv-rotate: $(objpfx)libresolv.so $(shared-thread-library)
diff --git a/resolv/tst-resolv-invalid-cname.c b/resolv/tst-resolv-invalid-cname.c
new file mode 100644
index 0000000000000000..ae2d4419b1978c02
--- /dev/null
+++ b/resolv/tst-resolv-invalid-cname.c
@@ -0,0 +1,406 @@
+/* Test handling of CNAMEs with non-host domain names (bug 12154).
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <netdb.h>
+#include <resolv.h>
+#include <stdlib.h>
+#include <string.h>
+#include <support/check.h>
+#include <support/check_nss.h>
+#include <support/resolv_test.h>
+#include <support/support.h>
+#include <support/xmemstream.h>
+
+/* Query strings describe the CNAME chain in the response. They have
+ the format "bitsBITS.countCOUNT.example.", where BITS and COUNT are
+ replaced by unsigned decimal numbers. COUNT is the number of CNAME
+ records in the response. BITS has two bits for each CNAME record,
+ describing a special prefix that is added to that CNAME.
+
+ 0: No special leading label.
+ 1: Starting with "*.".
+ 2: Starting with "-x.".
+ 3: Starting with "star.*.".
+
+ The first CNAME in the response using the two least significant
+ bits.
+
+ For PTR queries, the QNAME format is different, it is either
+ COUNT.BITS.168.192.in-addr.arpa. (with BITS and COUNT still
+ decimal), or:
+
+COUNT.BITS0.BITS1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
+
+ where BITS and COUNT are hexadecimal. */
+
+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);
+
+ /* The only other query type besides A is PTR. */
+ if (qtype != T_A && qtype != T_AAAA)
+ TEST_COMPARE (qtype, T_PTR);
+
+ unsigned int bits, bits1, count;
+ char *tail = NULL;
+ if (sscanf (qname, "bits%u.count%u.%ms", &bits, &count, &tail) == 3)
+ TEST_COMPARE_STRING (tail, "example");
+ else if (strstr (qname, "in-addr.arpa") != NULL
+ && sscanf (qname, "%u.%u.%ms", &bits, &count, &tail) == 3)
+ TEST_COMPARE_STRING (tail, "168.192.in-addr.arpa");
+ else if (sscanf (qname, "%x.%x.%x.%ms", &bits, &bits1, &count, &tail) == 4)
+ {
+ TEST_COMPARE_STRING (tail, "\
+0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa");
+ bits |= bits1 << 4;
+ }
+ else
+ FAIL_EXIT1 ("invalid QNAME: %s\n", qname);
+ free (tail);
+
+ struct resolv_response_flags flags = {};
+ resolv_response_init (b, flags);
+ resolv_response_add_question (b, qname, qclass, qtype);
+ resolv_response_section (b, ns_s_an);
+
+ /* Provide the requested number of CNAME records. */
+ char *previous_name = (char *) qname;
+ unsigned int original_bits = bits;
+ for (int unique = 0; unique < count; ++unique)
+ {
+ resolv_response_open_record (b, previous_name, qclass, T_CNAME, 60);
+
+ static const char bits_to_prefix[4][8] = { "", "*.", "-x.", "star.*." };
+ char *new_name = xasprintf ("%sunique%d.example",
+ bits_to_prefix[bits & 3], unique);
+ bits >>= 2;
+ resolv_response_add_name (b, new_name);
+ resolv_response_close_record (b);
+
+ if (previous_name != qname)
+ free (previous_name);
+ previous_name = new_name;
+ }
+
+ /* Actual answer record. */
+ resolv_response_open_record (b, previous_name, qclass, qtype, 60);
+ switch (qtype)
+ {
+ case T_A:
+ {
+ char ipv4[4] = {192, 168, count, original_bits};
+ resolv_response_add_data (b, &ipv4, sizeof (ipv4));
+ }
+ break;
+ case T_AAAA:
+ {
+ char ipv6[16] =
+ {
+ 0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ count, original_bits
+ };
+ resolv_response_add_data (b, &ipv6, sizeof (ipv6));
+ }
+ break;
+
+ case T_PTR:
+ {
+ char *name = xasprintf ("bits%u.count%u.example",
+ original_bits, count);
+ resolv_response_add_name (b, name);
+ free (name);
+ }
+ break;
+ }
+ resolv_response_close_record (b);
+
+ if (previous_name != qname)
+ free (previous_name);
+}
+
+/* Controls which name resolution function is invoked. */
+enum test_mode
+ {
+ byname, /* gethostbyname. */
+ byname2, /* gethostbyname2. */
+ gai, /* getaddrinfo without AI_CANONNAME. */
+ gai_canon, /* getaddrinfo with AI_CANONNAME. */
+
+ test_mode_num /* Number of enum values. */
+ };
+
+static const char *
+test_mode_to_string (enum test_mode mode)
+{
+ switch (mode)
+ {
+ case byname:
+ return "byname";
+ case byname2:
+ return "byname2";
+ case gai:
+ return "gai";
+ case gai_canon:
+ return "gai_canon";
+ case test_mode_num:
+ /* Report error below. */
+ }
+ FAIL_EXIT1 ("invalid test_mode: %d", mode);
+}
+
+/* Append the name and aliases to OUT. */
+static void
+append_names (FILE *out, const char *qname, int bits, int count,
+ enum test_mode mode)
+{
+ /* Largest valid index which has a corresponding zero in bits
+ (meaning a syntactically valid CNAME). */
+ int last_valid_cname = -1;
+
+ for (int i = 0; i < count; ++i)
+ if ((bits & (3 << (i * 2))) == 0)
+ last_valid_cname = i;
+
+ if (mode != gai)
+ {
+ const char *label;
+ if (mode == gai_canon)
+ label = "canonname";
+ else
+ label = "name";
+ if (last_valid_cname >= 0)
+ fprintf (out, "%s: unique%d.example\n", label, last_valid_cname);
+ else
+ fprintf (out, "%s: %s\n", label, qname);
+ }
+
+ if (mode == byname || mode == byname2)
+ {
+ if (last_valid_cname >= 0)
+ fprintf (out, "alias: %s\n", qname);
+ for (int i = 0; i < count; ++i)
+ {
+ if ((bits & (3 << (i * 2))) == 0 && i != last_valid_cname)
+ fprintf (out, "alias: unique%d.example\n", i);
+ }
+ }
+}
+
+/* Append the address information to OUT. */
+static void
+append_addresses (FILE *out, int af, int bits, int count, enum test_mode mode)
+{
+ int last = count * 256 + bits;
+ if (mode == gai || mode == gai_canon)
+ {
+ if (af == AF_INET || af == AF_UNSPEC)
+ fprintf (out, "address: STREAM/TCP 192.168.%d.%d 80\n", count, bits);
+ if (af == AF_INET6 || af == AF_UNSPEC)
+ {
+ if (last == 0)
+ fprintf (out, "address: STREAM/TCP 2001:db8:: 80\n");
+ else
+ fprintf (out, "address: STREAM/TCP 2001:db8::%x 80\n", last);
+ }
+ }
+ else
+ {
+ TEST_VERIFY (af != AF_UNSPEC);
+ if (af == AF_INET)
+ fprintf (out, "address: 192.168.%d.%d\n", count, bits);
+ if (af == AF_INET6)
+ {
+ if (last == 0)
+ fprintf (out, "address: 2001:db8::\n");
+ else
+ fprintf (out, "address: 2001:db8::%x\n", last);
+ }
+ }
+}
+
+/* Perform one test using a forward lookup. */
+static void
+check_forward (int af, int bits, int count, enum test_mode mode)
+{
+ char *qname = xasprintf ("bits%d.count%d.example", bits, count);
+ char *label = xasprintf ("af=%d bits=%d count=%d mode=%s qname=%s",
+ af, bits, count, test_mode_to_string (mode), qname);
+
+ struct xmemstream expected;
+ xopen_memstream (&expected);
+ if (mode == gai_canon)
+ fprintf (expected.out, "flags: AI_CANONNAME\n");
+ append_names (expected.out, qname, bits, count, mode);
+ append_addresses (expected.out, af, bits, count, mode);
+ xfclose_memstream (&expected);
+
+ if (mode == gai || mode == gai_canon)
+ {
+ struct addrinfo *ai;
+ struct addrinfo hints =
+ {
+ .ai_family = af,
+ .ai_socktype = SOCK_STREAM,
+ };
+ if (mode == gai_canon)
+ hints.ai_flags |= AI_CANONNAME;
+ int ret = getaddrinfo (qname, "80", &hints, &ai);
+ check_addrinfo (label, ai, ret, expected.buffer);
+ if (ret == 0)
+ freeaddrinfo (ai);
+ }
+ else
+ {
+ struct hostent *e;
+ if (mode == gai)
+ {
+ TEST_COMPARE (af, AF_INET);
+ e = gethostbyname (qname);
+ }
+ else
+ {
+ if (af != AF_INET)
+ TEST_COMPARE (af, AF_INET6);
+ e = gethostbyname2 (qname, af);
+ }
+ check_hostent (label, e, expected.buffer);
+ }
+
+ free (expected.buffer);
+ free (label);
+ free (qname);
+}
+
+/* Perform one check using a reverse lookup. */
+
+static void
+check_reverse (int af, int bits, int count)
+{
+ TEST_VERIFY (af == AF_INET || af == AF_INET6);
+
+ char *label = xasprintf ("af=%d bits=%d count=%d", af, bits, count);
+ char *fqdn = xasprintf ("bits%d.count%d.example", bits, count);
+
+ struct xmemstream expected;
+ xopen_memstream (&expected);
+ fprintf (expected.out, "name: %s\n", fqdn);
+ append_addresses (expected.out, af, bits, count, byname);
+ xfclose_memstream (&expected);
+
+ char addr[16] = { 0 };
+ socklen_t addrlen;
+ if (af == AF_INET)
+ {
+ addr[0] = 192;
+ addr[1] = 168;
+ addr[2] = count;
+ addr[3] = bits;
+ addrlen = 4;
+ }
+ else
+ {
+ addr[0] = 0x20;
+ addr[1] = 0x01;
+ addr[2] = 0x0d;
+ addr[3] = 0xb8;
+ addr[14] = count;
+ addr[15] = bits;
+ addrlen = 16;
+ }
+
+ struct hostent *e = gethostbyaddr (addr, addrlen, af);
+ check_hostent (label, e, expected.buffer);
+
+ /* getnameinfo check is different. There is no generic check_*
+ function for it. */
+ {
+ struct sockaddr_in sin = { };
+ struct sockaddr_in6 sin6 = { };
+ void *sa;
+ socklen_t salen;
+ if (af == AF_INET)
+ {
+ sin.sin_family = AF_INET;
+ memcpy (&sin.sin_addr, addr, addrlen);
+ sin.sin_port = htons (80);
+ sa = &sin;
+ salen = sizeof (sin);
+ }
+ else
+ {
+ sin6.sin6_family = AF_INET6;
+ memcpy (&sin6.sin6_addr, addr, addrlen);
+ sin6.sin6_port = htons (80);
+ sa = &sin6;
+ salen = sizeof (sin6);
+ }
+
+ char host[64];
+ char service[64];
+ int ret = getnameinfo (sa, salen, host,
+ sizeof (host), service, sizeof (service),
+ NI_NAMEREQD | NI_NUMERICSERV);
+ TEST_COMPARE (ret, 0);
+ TEST_COMPARE_STRING (host, fqdn);
+ TEST_COMPARE_STRING (service, "80");
+ }
+
+ free (expected.buffer);
+ free (fqdn);
+ free (label);
+}
+
+static int
+do_test (void)
+{
+ struct resolv_test *obj = resolv_test_start
+ ((struct resolv_redirect_config)
+ {
+ .response_callback = response
+ });
+
+ for (int count = 0; count <= 3; ++count)
+ for (int bits = 0; bits <= 1 << (count * 2); ++bits)
+ {
+ if (count > 0 && bits == count)
+ /* The last bits value is only checked if count == 0. */
+ continue;
+
+ for (enum test_mode mode = 0; mode < test_mode_num; ++mode)
+ {
+ check_forward (AF_INET, bits, count, mode);
+ if (mode != byname)
+ check_forward (AF_INET6, bits, count, mode);
+ if (mode == gai || mode == gai_canon)
+ check_forward (AF_UNSPEC, bits, count, mode);
+ }
+
+ check_reverse (AF_INET, bits, count);
+ check_reverse (AF_INET6, bits, count);
+ }
+
+ resolv_test_end (obj);
+
+ return 0;
+}
+
+#include <support/test-driver.c>