1 /*-
2 * SPDX-License-Identifier: (BSD-2-Clause-FreeBSD AND RSA-MD)
3 *
4 * Copyright (c) 2010, 2013 Zheng Liu <lz@freebsd.org>
5 * Copyright (c) 2012, Vyacheslav Matyushin
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31
32 /*
33 * The following notice applies to the code in ext2_half_md4():
34 *
35 * Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
36 *
37 * License to copy and use this software is granted provided that it
38 * is identified as the "RSA Data Security, Inc. MD4 Message-Digest
39 * Algorithm" in all material mentioning or referencing this software
40 * or this function.
41 *
42 * License is also granted to make and use derivative works provided
43 * that such works are identified as "derived from the RSA Data
44 * Security, Inc. MD4 Message-Digest Algorithm" in all material
45 * mentioning or referencing the derived work.
46 *
47 * RSA Data Security, Inc. makes no representations concerning either
48 * the merchantability of this software or the suitability of this
49 * software for any particular purpose. It is provided "as is"
50 * without express or implied warranty of any kind.
51 *
52 * These notices must be retained in any copies of any part of this
53 * documentation and/or software.
54 */
55
56 #include <sys/param.h>
57 #include <sys/systm.h>
58 #include <sys/conf.h>
59 #include <sys/vnode.h>
60 #include <sys/stat.h>
61 #include <sys/mount.h>
62
63 #include <vfs/ext2fs/ext2fs.h>
64 #include <vfs/ext2fs/fs.h>
65 #include <vfs/ext2fs/htree.h>
66 #include <vfs/ext2fs/inode.h>
67 #include <vfs/ext2fs/ext2_mount.h>
68 #include <vfs/ext2fs/ext2_extern.h>
69
70 SDT_PROVIDER_DECLARE(ext2fs);
71 /*
72 * ext2fs trace probe:
73 * arg0: verbosity. Higher numbers give more verbose messages
74 * arg1: Textual message
75 */
76 SDT_PROBE_DEFINE2(ext2fs, , trace, hash, "int", "char*");
77
78 /* F, G, and H are MD4 functions */
79 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
80 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
81 #define H(x, y, z) ((x) ^ (y) ^ (z))
82
83 /* ROTATE_LEFT rotates x left n bits */
84 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))
85
86 /*
87 * FF, GG, and HH are transformations for rounds 1, 2, and 3.
88 * Rotation is separated from addition to prevent recomputation.
89 */
90 #define FF(a, b, c, d, x, s) { \
91 (a) += F ((b), (c), (d)) + (x); \
92 (a) = ROTATE_LEFT ((a), (s)); \
93 }
94
95 #define GG(a, b, c, d, x, s) { \
96 (a) += G ((b), (c), (d)) + (x) + (uint32_t)0x5A827999; \
97 (a) = ROTATE_LEFT ((a), (s)); \
98 }
99
100 #define HH(a, b, c, d, x, s) { \
101 (a) += H ((b), (c), (d)) + (x) + (uint32_t)0x6ED9EBA1; \
102 (a) = ROTATE_LEFT ((a), (s)); \
103 }
104
105 /*
106 * MD4 basic transformation. It transforms state based on block.
107 *
108 * This is a half md4 algorithm since Linux uses this algorithm for dir
109 * index. This function is derived from the RSA Data Security, Inc. MD4
110 * Message-Digest Algorithm and was modified as necessary.
111 *
112 * The return value of this function is uint32_t in Linux, but actually we don't
113 * need to check this value, so in our version this function doesn't return any
114 * value.
115 */
116 static void
ext2_half_md4(uint32_t hash[4],uint32_t data[8])117 ext2_half_md4(uint32_t hash[4], uint32_t data[8])
118 {
119 uint32_t a = hash[0], b = hash[1], c = hash[2], d = hash[3];
120
121 /* Round 1 */
122 FF(a, b, c, d, data[0], 3);
123 FF(d, a, b, c, data[1], 7);
124 FF(c, d, a, b, data[2], 11);
125 FF(b, c, d, a, data[3], 19);
126 FF(a, b, c, d, data[4], 3);
127 FF(d, a, b, c, data[5], 7);
128 FF(c, d, a, b, data[6], 11);
129 FF(b, c, d, a, data[7], 19);
130
131 /* Round 2 */
132 GG(a, b, c, d, data[1], 3);
133 GG(d, a, b, c, data[3], 5);
134 GG(c, d, a, b, data[5], 9);
135 GG(b, c, d, a, data[7], 13);
136 GG(a, b, c, d, data[0], 3);
137 GG(d, a, b, c, data[2], 5);
138 GG(c, d, a, b, data[4], 9);
139 GG(b, c, d, a, data[6], 13);
140
141 /* Round 3 */
142 HH(a, b, c, d, data[3], 3);
143 HH(d, a, b, c, data[7], 9);
144 HH(c, d, a, b, data[2], 11);
145 HH(b, c, d, a, data[6], 15);
146 HH(a, b, c, d, data[1], 3);
147 HH(d, a, b, c, data[5], 9);
148 HH(c, d, a, b, data[0], 11);
149 HH(b, c, d, a, data[4], 15);
150
151 hash[0] += a;
152 hash[1] += b;
153 hash[2] += c;
154 hash[3] += d;
155 }
156
157 /*
158 * Tiny Encryption Algorithm.
159 */
160 static void
ext2_tea(uint32_t hash[4],uint32_t data[8])161 ext2_tea(uint32_t hash[4], uint32_t data[8])
162 {
163 uint32_t tea_delta = 0x9E3779B9;
164 uint32_t sum;
165 uint32_t x = hash[0], y = hash[1];
166 int n = 16;
167 int i = 1;
168
169 while (n-- > 0) {
170 sum = i * tea_delta;
171 x += ((y << 4) + data[0]) ^ (y + sum) ^ ((y >> 5) + data[1]);
172 y += ((x << 4) + data[2]) ^ (x + sum) ^ ((x >> 5) + data[3]);
173 i++;
174 }
175
176 hash[0] += x;
177 hash[1] += y;
178 }
179
180 static uint32_t
ext2_legacy_hash(const char * name,int len,int unsigned_char)181 ext2_legacy_hash(const char *name, int len, int unsigned_char)
182 {
183 uint32_t h0, h1 = 0x12A3FE2D, h2 = 0x37ABE8F9;
184 uint32_t multi = 0x6D22F5;
185 const unsigned char *uname = (const unsigned char *)name;
186 const signed char *sname = (const signed char *)name;
187 int val, i;
188
189 for (i = 0; i < len; i++) {
190 if (unsigned_char)
191 val = (u_int)*uname++;
192 else
193 val = (int)*sname++;
194
195 h0 = h2 + (h1 ^ (val * multi));
196 if (h0 & 0x80000000)
197 h0 -= 0x7FFFFFFF;
198 h2 = h1;
199 h1 = h0;
200 }
201
202 return (h1 << 1);
203 }
204
205 static void
ext2_prep_hashbuf(const char * src,int slen,uint32_t * dst,int dlen,int unsigned_char)206 ext2_prep_hashbuf(const char *src, int slen, uint32_t *dst, int dlen,
207 int unsigned_char)
208 {
209 uint32_t padding = slen | (slen << 8) | (slen << 16) | (slen << 24);
210 uint32_t buf_val;
211 const unsigned char *ubuf = (const unsigned char *)src;
212 const signed char *sbuf = (const signed char *)src;
213 int len, i;
214 int buf_byte;
215
216 if (slen > dlen)
217 len = dlen;
218 else
219 len = slen;
220
221 buf_val = padding;
222
223 for (i = 0; i < len; i++) {
224 if (unsigned_char)
225 buf_byte = (u_int)ubuf[i];
226 else
227 buf_byte = (int)sbuf[i];
228
229 if ((i % 4) == 0)
230 buf_val = padding;
231
232 buf_val <<= 8;
233 buf_val += buf_byte;
234
235 if ((i % 4) == 3) {
236 *dst++ = buf_val;
237 dlen -= sizeof(uint32_t);
238 buf_val = padding;
239 }
240 }
241
242 dlen -= sizeof(uint32_t);
243 if (dlen >= 0)
244 *dst++ = buf_val;
245
246 dlen -= sizeof(uint32_t);
247 while (dlen >= 0) {
248 *dst++ = padding;
249 dlen -= sizeof(uint32_t);
250 }
251 }
252
253 int
ext2_htree_hash(const char * name,int len,uint32_t * hash_seed,int hash_version,uint32_t * hash_major,uint32_t * hash_minor)254 ext2_htree_hash(const char *name, int len,
255 uint32_t *hash_seed, int hash_version,
256 uint32_t *hash_major, uint32_t *hash_minor)
257 {
258 uint32_t hash[4];
259 uint32_t data[8];
260 uint32_t major = 0, minor = 0;
261 int unsigned_char = 0;
262
263 if (!name || !hash_major)
264 return (-1);
265
266 if (len < 1 || len > 255)
267 goto error;
268
269 hash[0] = 0x67452301;
270 hash[1] = 0xEFCDAB89;
271 hash[2] = 0x98BADCFE;
272 hash[3] = 0x10325476;
273
274 if (hash_seed)
275 memcpy(hash, hash_seed, sizeof(hash));
276
277 switch (hash_version) {
278 case EXT2_HTREE_TEA_UNSIGNED:
279 unsigned_char = 1;
280 /* FALLTHROUGH */
281 case EXT2_HTREE_TEA:
282 while (len > 0) {
283 ext2_prep_hashbuf(name, len, data, 16, unsigned_char);
284 ext2_tea(hash, data);
285 len -= 16;
286 name += 16;
287 }
288 major = hash[0];
289 minor = hash[1];
290 break;
291 case EXT2_HTREE_LEGACY_UNSIGNED:
292 unsigned_char = 1;
293 /* FALLTHROUGH */
294 case EXT2_HTREE_LEGACY:
295 major = ext2_legacy_hash(name, len, unsigned_char);
296 break;
297 case EXT2_HTREE_HALF_MD4_UNSIGNED:
298 unsigned_char = 1;
299 /* FALLTHROUGH */
300 case EXT2_HTREE_HALF_MD4:
301 while (len > 0) {
302 ext2_prep_hashbuf(name, len, data, 32, unsigned_char);
303 ext2_half_md4(hash, data);
304 len -= 32;
305 name += 32;
306 }
307 major = hash[1];
308 minor = hash[2];
309 break;
310 default:
311 SDT_PROBE2(ext2fs, , trace, hash, 1, "unexpected hash version");
312 goto error;
313 }
314
315 major &= ~1;
316 if (major == (EXT2_HTREE_EOF << 1))
317 major = (EXT2_HTREE_EOF - 1) << 1;
318 *hash_major = major;
319 if (hash_minor)
320 *hash_minor = minor;
321
322 return (0);
323
324 error:
325 *hash_major = 0;
326 if (hash_minor)
327 *hash_minor = 0;
328 return (-1);
329 }
330