1 /*-
2 * Copyright (c) 2009 David Schultz <[email protected]>
3 * Copyright (c) 2023 The FreeBSD Foundation
4 * All rights reserved.
5 *
6 * Portions of this software were developed by Robert Clausecker
7 * <[email protected]> under sponsorship 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
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/mman.h>
34 #include <assert.h>
35 #include <dlfcn.h>
36 #include <limits.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40
41 #include <atf-c.h>
42
43 void *(*memccpy_fn)(void *restrict, const void *restrict, int, size_t);
44
45 static char *
makebuf(size_t len,int guard_at_end)46 makebuf(size_t len, int guard_at_end)
47 {
48 char *buf;
49 size_t alloc_size, page_size;
50
51 page_size = getpagesize();
52 alloc_size = roundup2(len, page_size) + page_size;
53
54 buf = mmap(NULL, alloc_size, PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
55 assert(buf);
56 if (guard_at_end) {
57 assert(munmap(buf + alloc_size - page_size, page_size) == 0);
58 return (buf + alloc_size - page_size - len);
59 } else {
60 assert(munmap(buf, page_size) == 0);
61 return (buf + page_size);
62 }
63 }
64
65 static void
test_memccpy(const char * s)66 test_memccpy(const char *s)
67 {
68 char *src, *dst, *expected;
69 size_t size, bufsize, x;
70 int i, j;
71
72 size = strlen(s) + 1;
73 for (i = 0; i <= 1; i++) {
74 for (j = 0; j <= 1; j++) {
75 for (bufsize = 0; bufsize <= size + 10; bufsize++) {
76 src = makebuf(size, i);
77 memcpy(src, s, size);
78 dst = makebuf(bufsize, j);
79 memset(dst, 'X', bufsize);
80 expected = bufsize >= size ? dst + size : NULL;
81 assert(memccpy_fn(dst, src, src[size-1], bufsize) == expected);
82 assert(bufsize == 0 || strncmp(src, dst, bufsize - 1) == 0);
83 for (x = size; x < bufsize; x++)
84 assert(dst[x] == 'X');
85 }
86 }
87 }
88 }
89
90 static void
test_sentinel(char * dest,char * src,size_t destlen,size_t srclen)91 test_sentinel(char *dest, char *src, size_t destlen, size_t srclen)
92 {
93 size_t i, effective_len;
94 void *res, *wantres;
95 const char *fail = NULL;
96 char terminator;
97
98 for (i = 0; i < srclen; i++)
99 /* src will never include (){} */
100 src[i] = '0' + i;
101
102 /* source sentinels: not to be copied */
103 src[-1] = '(';
104 src[srclen] = ')';
105
106 memset(dest, '\xee', destlen);
107
108 /* destination sentinels: not to be touched */
109 dest[-1] = '{';
110 dest[destlen] = '}';
111
112 effective_len = srclen < destlen ? srclen : destlen;
113 wantres = srclen <= destlen ? dest + srclen : NULL;
114 terminator = src[srclen-1];
115 res = memccpy_fn(dest, src, terminator, destlen);
116
117 if (dest[-1] != '{')
118 fail = "start sentinel overwritten";
119 else if (dest[destlen] != '}')
120 fail = "end sentinel overwritten";
121 else if (res != wantres)
122 fail = "incorrect return value";
123 else if (destlen > 0 && memcmp(src, dest, effective_len) != 0)
124 fail = "string not copied correctly";
125 else for (i = srclen; i < destlen; i++)
126 if (dest[i] != '\xee') {
127 fail = "buffer mutilated behind string";
128 break;
129 }
130
131 if (fail)
132 atf_tc_fail_nonfatal("%s\n"
133 "memccpy(%p \"%s\", %p \"%s\", %u '%c', %zu) = %p (want %p)\n",
134 fail, dest, dest, src, src, terminator, terminator, destlen, res, wantres);
135 }
136
137 ATF_TC_WITHOUT_HEAD(null);
ATF_TC_BODY(null,tc)138 ATF_TC_BODY(null, tc)
139 {
140 ATF_CHECK_EQ(memccpy_fn(NULL, "foo", 42, 0), NULL);
141 }
142
143 ATF_TC(zero_extension);
ATF_TC_HEAD(zero_extension,tc)144 ATF_TC_HEAD(zero_extension, tc)
145 {
146 atf_tc_set_md_var(tc, "descr",
147 "Ensure the upper bits of the terminator are ignored");
148 }
ATF_TC_BODY(zero_extension,tc)149 ATF_TC_BODY(zero_extension, tc)
150 {
151 int mask = -1 & ~UCHAR_MAX;
152 char buf[16];
153
154 memset(buf, 0xcc, sizeof(buf));
155 ATF_CHECK_EQ(memccpy(buf, "foobar", 'r', sizeof(buf)), buf + sizeof("foobar") - 1);
156 ATF_CHECK_EQ(memcmp(buf, "foobar", sizeof("foobar") - 1), 0);
157
158 memset(buf, 0xcc, sizeof(buf));
159 ATF_CHECK_EQ(memccpy(buf, "foobar", mask | 'r', sizeof(buf)), buf + sizeof("foobar") - 1);
160 ATF_CHECK_EQ(memcmp(buf, "foobar", sizeof("foobar") - 1), 0);
161 }
162
163 ATF_TC_WITHOUT_HEAD(bounds);
ATF_TC_BODY(bounds,tc)164 ATF_TC_BODY(bounds, tc)
165 {
166 size_t i;
167 char buf[64];
168
169 for (i = 0; i < sizeof(buf) - 1; i++) {
170 buf[i] = ' ' + i;
171 test_memccpy(buf);
172 }
173 }
174
175 ATF_TC_WITHOUT_HEAD(alignments);
ATF_TC_BODY(alignments,tc)176 ATF_TC_BODY(alignments, tc)
177 {
178 size_t srcalign, destalign, srclen, destlen;
179 char src[15+2+64]; /* 15 offsets + 64 max length + sentinels */
180 char dest[15+2+64]; /* 15 offsets + 64 max length + sentinels */
181
182 for (srcalign = 0; srcalign < 16; srcalign++)
183 for (destalign = 0; destalign < 16; destalign++)
184 for (srclen = 1; srclen < 64; srclen++)
185 for (destlen = 0; destlen < 64; destlen++)
186 test_sentinel(dest+destalign+1,
187 src+srcalign+1, destlen, srclen);
188 }
189
ATF_TP_ADD_TCS(tp)190 ATF_TP_ADD_TCS(tp)
191 {
192 void *dl_handle;
193
194 dl_handle = dlopen(NULL, RTLD_LAZY);
195 memccpy_fn = dlsym(dl_handle, "test_memccpy");
196 if (memccpy_fn == NULL)
197 memccpy_fn = memccpy;
198
199 ATF_TP_ADD_TC(tp, null);
200 ATF_TP_ADD_TC(tp, zero_extension);
201 ATF_TP_ADD_TC(tp, bounds);
202 ATF_TP_ADD_TC(tp, alignments);
203
204 return (atf_no_error());
205 }
206