1 /*- 2 * Copyright (c) 2009 David Schultz <das@FreeBSD.org> 3 * Copyright (c) 2023 The FreeBSD Foundation 4 * All rights reserved. 5 * 6 * Portions of this software were developed by Robert Clausecker 7 * <fuz@FreeBSD.org> 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 * 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 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 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); 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); 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 } 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); 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); 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 } 189 190 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