1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2019 The FreeBSD Foundation
5 *
6 * This software was developed by BFF Storage Systems, LLC under sponsorship
7 * from the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31extern "C" {
32#include <sys/param.h>
33
34#include <unistd.h>
35}
36
37#include "mockfs.hh"
38#include "utils.hh"
39
40using namespace testing;
41
42class Readlink: public FuseTest {
43public:
44void expect_lookup(const char *relpath, uint64_t ino)
45{
46	FuseTest::expect_lookup(relpath, ino, S_IFLNK | 0777, 0, 1);
47}
48void expect_readlink(uint64_t ino, ProcessMockerT r)
49{
50	EXPECT_CALL(*m_mock, process(
51		ResultOf([=](auto in) {
52			return (in.header.opcode == FUSE_READLINK &&
53				in.header.nodeid == ino);
54		}, Eq(true)),
55		_)
56	).WillOnce(Invoke(r));
57}
58
59};
60
61class PushSymlinksIn: public Readlink {
62	virtual void SetUp() {
63		m_push_symlinks_in = true;
64		Readlink::SetUp();
65	}
66};
67
68TEST_F(Readlink, eloop)
69{
70	const char FULLPATH[] = "mountpoint/src";
71	const char RELPATH[] = "src";
72	const uint64_t ino = 42;
73	char buf[80];
74
75	expect_lookup(RELPATH, ino);
76	expect_readlink(ino, ReturnErrno(ELOOP));
77
78	EXPECT_EQ(-1, readlink(FULLPATH, buf, sizeof(buf)));
79	EXPECT_EQ(ELOOP, errno);
80}
81
82/*
83 * If a malicious or buggy server returns a NUL in the FUSE_READLINK result, it
84 * should be handled gracefully.
85 * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274268
86 */
87TEST_F(Readlink, embedded_nul)
88{
89	const char FULLPATH[] = "mountpoint/src";
90	const char RELPATH[] = "src";
91	const char dst[] = "dst\0stuff";
92	char buf[80];
93	const uint64_t ino = 42;
94
95	EXPECT_LOOKUP(FUSE_ROOT_ID, RELPATH)
96	.WillOnce(Invoke(ReturnImmediate([=](auto in __unused, auto& out) {
97		SET_OUT_HEADER_LEN(out, entry);
98		out.body.entry.attr.mode = S_IFLNK | 0777;
99		out.body.entry.nodeid = ino;
100		out.body.entry.attr_valid = UINT64_MAX;
101		out.body.entry.entry_valid = UINT64_MAX;
102	})));
103
104	EXPECT_CALL(*m_mock, process(
105		ResultOf([=](auto in) {
106			return (in.header.opcode == FUSE_READLINK &&
107				in.header.nodeid == ino);
108		}, Eq(true)),
109		_)
110	).WillRepeatedly(Invoke(ReturnImmediate([=](auto in __unused, auto& out) {
111		memcpy(out.body.str, dst, sizeof(dst));
112		out.header.len = sizeof(out.header) + sizeof(dst) + 1;
113	})));
114
115	EXPECT_EQ(-1, readlink(FULLPATH, buf, sizeof(buf)));
116	EXPECT_EQ(EIO, errno);
117	EXPECT_EQ(-1, access(FULLPATH, R_OK));
118	EXPECT_EQ(EIO, errno);
119}
120
121TEST_F(Readlink, ok)
122{
123	const char FULLPATH[] = "mountpoint/src";
124	const char RELPATH[] = "src";
125	const char dst[] = "dst";
126	const uint64_t ino = 42;
127	char buf[80];
128
129	expect_lookup(RELPATH, ino);
130	expect_readlink(ino, ReturnImmediate([=](auto in __unused, auto& out) {
131		strlcpy(out.body.str, dst, sizeof(out.body.str));
132		out.header.len = sizeof(out.header) + strlen(dst) + 1;
133	}));
134
135	EXPECT_EQ(static_cast<ssize_t>(strlen(dst)) + 1,
136		  readlink(FULLPATH, buf, sizeof(buf)));
137	EXPECT_STREQ(dst, buf);
138}
139
140TEST_F(PushSymlinksIn, readlink)
141{
142	const char FULLPATH[] = "mountpoint/src";
143	const char RELPATH[] = "src";
144	const char dst[] = "/dst";
145	const uint64_t ino = 42;
146	char buf[MAXPATHLEN], wd[MAXPATHLEN], want[MAXPATHLEN];
147	int len;
148
149	expect_lookup(RELPATH, ino);
150	expect_readlink(ino, ReturnImmediate([=](auto in __unused, auto& out) {
151		strlcpy(out.body.str, dst, sizeof(out.body.str));
152		out.header.len = sizeof(out.header) + strlen(dst) + 1;
153	}));
154
155	ASSERT_NE(nullptr, getcwd(wd, sizeof(wd))) << strerror(errno);
156	len = snprintf(want, sizeof(want), "%s/mountpoint%s", wd, dst);
157	ASSERT_LE(0, len) << strerror(errno);
158
159	EXPECT_EQ(static_cast<ssize_t>(len) + 1,
160		readlink(FULLPATH, buf, sizeof(buf)));
161	EXPECT_STREQ(want, buf);
162}
163