1/*	$NetBSD: t_rtld_r_debug.c,v 1.5 2023/11/24 17:40:20 riastradh Exp $	*/
2
3/*
4 * Copyright (c) 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
17 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
23 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
27 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/types.h>
31
32#include <atf-c.h>
33#include <dlfcn.h>
34#include <link_elf.h>
35#include <stdbool.h>
36
37#include "h_macros.h"
38
39static long int
40getauxval(unsigned int type)
41{
42	const AuxInfo *aux;
43
44	for (aux = _dlauxinfo(); aux->a_type != AT_NULL; ++aux) {
45		if (type == aux->a_type)
46			return aux->a_v;
47	}
48
49	return 0;
50}
51
52static Elf_Dyn *
53get_dynamic_section(void)
54{
55	uintptr_t relocbase = (uintptr_t)~0U;
56	const Elf_Phdr *phdr;
57	Elf_Half phnum;
58	const Elf_Phdr *phlimit, *dynphdr;
59
60	phdr = (void *)getauxval(AT_PHDR);
61	phnum = (Elf_Half)getauxval(AT_PHNUM);
62
63	ATF_CHECK(phdr != NULL);
64	ATF_CHECK(phnum != (Elf_Half)~0);
65
66	phlimit = phdr + phnum;
67	dynphdr = NULL;
68
69	for (; phdr < phlimit; ++phdr) {
70		if (phdr->p_type == PT_DYNAMIC)
71			dynphdr = phdr;
72		if (phdr->p_type == PT_PHDR)
73			relocbase = (uintptr_t)phdr - phdr->p_vaddr;
74	}
75
76	return (Elf_Dyn *)((uint8_t *)dynphdr->p_vaddr + relocbase);
77}
78
79static struct r_debug *
80get_rtld_r_debug(void)
81{
82	struct r_debug *debug = NULL;
83	Elf_Dyn *dynp;
84
85	for (dynp = get_dynamic_section(); dynp->d_tag != DT_NULL; dynp++) {
86		if (dynp->d_tag == DT_DEBUG) {
87			debug = (void *)dynp->d_un.d_val;
88			break;
89		}
90	}
91	ATF_CHECK(debug != NULL);
92
93	return debug;
94}
95
96static void
97check_r_debug_return_link_map(const char *name, struct link_map **rmap)
98{
99	struct r_debug *debug;
100	struct link_map *map;
101	void *loader;
102	bool found;
103
104	loader = NULL;
105	debug = get_rtld_r_debug();
106	ATF_CHECK(debug != NULL);
107	ATF_CHECK_EQ_MSG(debug->r_version, R_DEBUG_VERSION,
108	    "debug->r_version=%d R_DEBUG_VERSION=%d",
109	    debug->r_version, R_DEBUG_VERSION);
110	map = debug->r_map;
111	ATF_CHECK(map != NULL);
112
113	for (found = false; map; map = map->l_next) {
114		if (strstr(map->l_name, name) != NULL) {
115			if (rmap)
116				*rmap = map;
117			found = true;
118		} else if (strstr(map->l_name, "ld.elf_so") != NULL) {
119			loader = (void *)map->l_addr;
120		}
121	}
122	ATF_CHECK(found);
123	ATF_CHECK(loader != NULL);
124	ATF_CHECK(debug->r_brk != NULL);
125	ATF_CHECK_EQ_MSG(debug->r_state, RT_CONSISTENT,
126	    "debug->r_state=%d RT_CONSISTENT=%d",
127	    debug->r_state, RT_CONSISTENT);
128	ATF_CHECK_EQ_MSG(debug->r_ldbase, loader,
129	    "debug->r_ldbase=%p loader=%p",
130	    debug->r_ldbase, loader);
131}
132
133ATF_TC(self);
134ATF_TC_HEAD(self, tc)
135{
136	atf_tc_set_md_var(tc, "descr", "check whether r_debug is well-formed");
137}
138ATF_TC_BODY(self, tc)
139{
140	check_r_debug_return_link_map("t_rtld_r_debug", NULL);
141}
142
143ATF_TC(dlopen);
144ATF_TC_HEAD(dlopen, tc)
145{
146	atf_tc_set_md_var(tc, "descr",
147	    "check whether r_debug is well-formed after an dlopen(3) call");
148}
149ATF_TC_BODY(dlopen, tc)
150{
151	void *handle;
152	struct link_map *map, *r_map;
153
154	handle = dlopen("libutil.so", RTLD_LAZY);
155	ATF_REQUIRE_MSG(handle, "dlopen: %s", dlerror());
156
157	check_r_debug_return_link_map("libutil.so", &r_map);
158
159	ATF_REQUIRE_EQ_MSG(dlinfo(handle, RTLD_DI_LINKMAP, &map), 0,
160	    "dlinfo: %s", dlerror());
161
162	ATF_CHECK_EQ_MSG(map, r_map, "map=%p r_map=%p", map, r_map);
163	ATF_CHECK_EQ_MSG(dlclose(handle), 0, "dlclose: %s", dlerror());
164}
165
166ATF_TP_ADD_TCS(tp)
167{
168	ATF_TP_ADD_TC(tp, self);
169	ATF_TP_ADD_TC(tp, dlopen);
170	return atf_no_error();
171}
172