xref: /linux/scripts/mod/sumversion.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 #include <netinet/in.h>
2 #ifdef __sun__
3 #include <inttypes.h>
4 #else
5 #include <stdint.h>
6 #endif
7 #include <ctype.h>
8 #include <errno.h>
9 #include <string.h>
10 #include "modpost.h"
11 
12 /*
13  * Stolen form Cryptographic API.
14  *
15  * MD4 Message Digest Algorithm (RFC1320).
16  *
17  * Implementation derived from Andrew Tridgell and Steve French's
18  * CIFS MD4 implementation, and the cryptoapi implementation
19  * originally based on the public domain implementation written
20  * by Colin Plumb in 1993.
21  *
22  * Copyright (c) Andrew Tridgell 1997-1998.
23  * Modified by Steve French (sfrench@us.ibm.com) 2002
24  * Copyright (c) Cryptoapi developers.
25  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
26  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
27  *
28  * This program is free software; you can redistribute it and/or modify
29  * it under the terms of the GNU General Public License as published by
30  * the Free Software Foundation; either version 2 of the License, or
31  * (at your option) any later version.
32  *
33  */
34 #define MD4_DIGEST_SIZE		16
35 #define MD4_HMAC_BLOCK_SIZE	64
36 #define MD4_BLOCK_WORDS		16
37 #define MD4_HASH_WORDS		4
38 
39 struct md4_ctx {
40 	uint32_t hash[MD4_HASH_WORDS];
41 	uint32_t block[MD4_BLOCK_WORDS];
42 	uint64_t byte_count;
43 };
44 
45 static inline uint32_t lshift(uint32_t x, unsigned int s)
46 {
47 	x &= 0xFFFFFFFF;
48 	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
49 }
50 
51 static inline uint32_t F(uint32_t x, uint32_t y, uint32_t z)
52 {
53 	return (x & y) | ((~x) & z);
54 }
55 
56 static inline uint32_t G(uint32_t x, uint32_t y, uint32_t z)
57 {
58 	return (x & y) | (x & z) | (y & z);
59 }
60 
61 static inline uint32_t H(uint32_t x, uint32_t y, uint32_t z)
62 {
63 	return x ^ y ^ z;
64 }
65 
66 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
67 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (uint32_t)0x5A827999,s))
68 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (uint32_t)0x6ED9EBA1,s))
69 
70 /* XXX: this stuff can be optimized */
71 static inline void le32_to_cpu_array(uint32_t *buf, unsigned int words)
72 {
73 	while (words--) {
74 		*buf = ntohl(*buf);
75 		buf++;
76 	}
77 }
78 
79 static inline void cpu_to_le32_array(uint32_t *buf, unsigned int words)
80 {
81 	while (words--) {
82 		*buf = htonl(*buf);
83 		buf++;
84 	}
85 }
86 
87 static void md4_transform(uint32_t *hash, uint32_t const *in)
88 {
89 	uint32_t a, b, c, d;
90 
91 	a = hash[0];
92 	b = hash[1];
93 	c = hash[2];
94 	d = hash[3];
95 
96 	ROUND1(a, b, c, d, in[0], 3);
97 	ROUND1(d, a, b, c, in[1], 7);
98 	ROUND1(c, d, a, b, in[2], 11);
99 	ROUND1(b, c, d, a, in[3], 19);
100 	ROUND1(a, b, c, d, in[4], 3);
101 	ROUND1(d, a, b, c, in[5], 7);
102 	ROUND1(c, d, a, b, in[6], 11);
103 	ROUND1(b, c, d, a, in[7], 19);
104 	ROUND1(a, b, c, d, in[8], 3);
105 	ROUND1(d, a, b, c, in[9], 7);
106 	ROUND1(c, d, a, b, in[10], 11);
107 	ROUND1(b, c, d, a, in[11], 19);
108 	ROUND1(a, b, c, d, in[12], 3);
109 	ROUND1(d, a, b, c, in[13], 7);
110 	ROUND1(c, d, a, b, in[14], 11);
111 	ROUND1(b, c, d, a, in[15], 19);
112 
113 	ROUND2(a, b, c, d,in[ 0], 3);
114 	ROUND2(d, a, b, c, in[4], 5);
115 	ROUND2(c, d, a, b, in[8], 9);
116 	ROUND2(b, c, d, a, in[12], 13);
117 	ROUND2(a, b, c, d, in[1], 3);
118 	ROUND2(d, a, b, c, in[5], 5);
119 	ROUND2(c, d, a, b, in[9], 9);
120 	ROUND2(b, c, d, a, in[13], 13);
121 	ROUND2(a, b, c, d, in[2], 3);
122 	ROUND2(d, a, b, c, in[6], 5);
123 	ROUND2(c, d, a, b, in[10], 9);
124 	ROUND2(b, c, d, a, in[14], 13);
125 	ROUND2(a, b, c, d, in[3], 3);
126 	ROUND2(d, a, b, c, in[7], 5);
127 	ROUND2(c, d, a, b, in[11], 9);
128 	ROUND2(b, c, d, a, in[15], 13);
129 
130 	ROUND3(a, b, c, d,in[ 0], 3);
131 	ROUND3(d, a, b, c, in[8], 9);
132 	ROUND3(c, d, a, b, in[4], 11);
133 	ROUND3(b, c, d, a, in[12], 15);
134 	ROUND3(a, b, c, d, in[2], 3);
135 	ROUND3(d, a, b, c, in[10], 9);
136 	ROUND3(c, d, a, b, in[6], 11);
137 	ROUND3(b, c, d, a, in[14], 15);
138 	ROUND3(a, b, c, d, in[1], 3);
139 	ROUND3(d, a, b, c, in[9], 9);
140 	ROUND3(c, d, a, b, in[5], 11);
141 	ROUND3(b, c, d, a, in[13], 15);
142 	ROUND3(a, b, c, d, in[3], 3);
143 	ROUND3(d, a, b, c, in[11], 9);
144 	ROUND3(c, d, a, b, in[7], 11);
145 	ROUND3(b, c, d, a, in[15], 15);
146 
147 	hash[0] += a;
148 	hash[1] += b;
149 	hash[2] += c;
150 	hash[3] += d;
151 }
152 
153 static inline void md4_transform_helper(struct md4_ctx *ctx)
154 {
155 	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(uint32_t));
156 	md4_transform(ctx->hash, ctx->block);
157 }
158 
159 static void md4_init(struct md4_ctx *mctx)
160 {
161 	mctx->hash[0] = 0x67452301;
162 	mctx->hash[1] = 0xefcdab89;
163 	mctx->hash[2] = 0x98badcfe;
164 	mctx->hash[3] = 0x10325476;
165 	mctx->byte_count = 0;
166 }
167 
168 static void md4_update(struct md4_ctx *mctx,
169 		       const unsigned char *data, unsigned int len)
170 {
171 	const uint32_t avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
172 
173 	mctx->byte_count += len;
174 
175 	if (avail > len) {
176 		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
177 		       data, len);
178 		return;
179 	}
180 
181 	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
182 	       data, avail);
183 
184 	md4_transform_helper(mctx);
185 	data += avail;
186 	len -= avail;
187 
188 	while (len >= sizeof(mctx->block)) {
189 		memcpy(mctx->block, data, sizeof(mctx->block));
190 		md4_transform_helper(mctx);
191 		data += sizeof(mctx->block);
192 		len -= sizeof(mctx->block);
193 	}
194 
195 	memcpy(mctx->block, data, len);
196 }
197 
198 static void md4_final_ascii(struct md4_ctx *mctx, char *out, unsigned int len)
199 {
200 	const unsigned int offset = mctx->byte_count & 0x3f;
201 	char *p = (char *)mctx->block + offset;
202 	int padding = 56 - (offset + 1);
203 
204 	*p++ = 0x80;
205 	if (padding < 0) {
206 		memset(p, 0x00, padding + sizeof (uint64_t));
207 		md4_transform_helper(mctx);
208 		p = (char *)mctx->block;
209 		padding = 56;
210 	}
211 
212 	memset(p, 0, padding);
213 	mctx->block[14] = mctx->byte_count << 3;
214 	mctx->block[15] = mctx->byte_count >> 29;
215 	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
216 	                  sizeof(uint64_t)) / sizeof(uint32_t));
217 	md4_transform(mctx->hash, mctx->block);
218 	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(uint32_t));
219 
220 	snprintf(out, len, "%08X%08X%08X%08X",
221 		 mctx->hash[0], mctx->hash[1], mctx->hash[2], mctx->hash[3]);
222 }
223 
224 static inline void add_char(unsigned char c, struct md4_ctx *md)
225 {
226 	md4_update(md, &c, 1);
227 }
228 
229 static int parse_string(const char *file, unsigned long len,
230 			struct md4_ctx *md)
231 {
232 	unsigned long i;
233 
234 	add_char(file[0], md);
235 	for (i = 1; i < len; i++) {
236 		add_char(file[i], md);
237 		if (file[i] == '"' && file[i-1] != '\\')
238 			break;
239 	}
240 	return i;
241 }
242 
243 static int parse_comment(const char *file, unsigned long len)
244 {
245 	unsigned long i;
246 
247 	for (i = 2; i < len; i++) {
248 		if (file[i-1] == '*' && file[i] == '/')
249 			break;
250 	}
251 	return i;
252 }
253 
254 /* FIXME: Handle .s files differently (eg. # starts comments) --RR */
255 static int parse_file(const char *fname, struct md4_ctx *md)
256 {
257 	char *file;
258 	unsigned long i, len;
259 
260 	file = grab_file(fname, &len);
261 	if (!file)
262 		return 0;
263 
264 	for (i = 0; i < len; i++) {
265 		/* Collapse and ignore \ and CR. */
266 		if (file[i] == '\\' && (i+1 < len) && file[i+1] == '\n') {
267 			i++;
268 			continue;
269 		}
270 
271 		/* Ignore whitespace */
272 		if (isspace(file[i]))
273 			continue;
274 
275 		/* Handle strings as whole units */
276 		if (file[i] == '"') {
277 			i += parse_string(file+i, len - i, md);
278 			continue;
279 		}
280 
281 		/* Comments: ignore */
282 		if (file[i] == '/' && file[i+1] == '*') {
283 			i += parse_comment(file+i, len - i);
284 			continue;
285 		}
286 
287 		add_char(file[i], md);
288 	}
289 	release_file(file, len);
290 	return 1;
291 }
292 
293 /* We have dir/file.o.  Open dir/.file.o.cmd, look for deps_ line to
294  * figure out source file. */
295 static int parse_source_files(const char *objfile, struct md4_ctx *md)
296 {
297 	char *cmd, *file, *line, *dir;
298 	const char *base;
299 	unsigned long flen, pos = 0;
300 	int dirlen, ret = 0, check_files = 0;
301 
302 	cmd = NOFAIL(malloc(strlen(objfile) + sizeof("..cmd")));
303 
304 	base = strrchr(objfile, '/');
305 	if (base) {
306 		base++;
307 		dirlen = base - objfile;
308 		sprintf(cmd, "%.*s.%s.cmd", dirlen, objfile, base);
309 	} else {
310 		dirlen = 0;
311 		sprintf(cmd, ".%s.cmd", objfile);
312 	}
313 	dir = NOFAIL(malloc(dirlen + 1));
314 	strncpy(dir, objfile, dirlen);
315 	dir[dirlen] = '\0';
316 
317 	file = grab_file(cmd, &flen);
318 	if (!file) {
319 		warn("could not find %s for %s\n", cmd, objfile);
320 		goto out;
321 	}
322 
323 	/* There will be a line like so:
324 		deps_drivers/net/dummy.o := \
325 		  drivers/net/dummy.c \
326 		    $(wildcard include/config/net/fastroute.h) \
327 		  include/linux/config.h \
328 		    $(wildcard include/config/h.h) \
329 		  include/linux/module.h \
330 
331 	   Sum all files in the same dir or subdirs.
332 	*/
333 	while ((line = get_next_line(&pos, file, flen)) != NULL) {
334 		char* p = line;
335 		if (strncmp(line, "deps_", sizeof("deps_")-1) == 0) {
336 			check_files = 1;
337 			continue;
338 		}
339 		if (!check_files)
340 			continue;
341 
342 		/* Continue until line does not end with '\' */
343 		if ( *(p + strlen(p)-1) != '\\')
344 			break;
345 		/* Terminate line at first space, to get rid of final ' \' */
346 		while (*p) {
347                        if (isspace(*p)) {
348 				*p = '\0';
349 				break;
350 			}
351 			p++;
352 		}
353 
354 		/* Check if this file is in same dir as objfile */
355 		if ((strstr(line, dir)+strlen(dir)-1) == strrchr(line, '/')) {
356 			if (!parse_file(line, md)) {
357 				warn("could not open %s: %s\n",
358 				     line, strerror(errno));
359 				goto out_file;
360 			}
361 
362 		}
363 
364 	}
365 
366 	/* Everyone parsed OK */
367 	ret = 1;
368 out_file:
369 	release_file(file, flen);
370 out:
371 	free(dir);
372 	free(cmd);
373 	return ret;
374 }
375 
376 /* Calc and record src checksum. */
377 void get_src_version(const char *modname, char sum[], unsigned sumlen)
378 {
379 	void *file;
380 	unsigned long len;
381 	struct md4_ctx md;
382 	char *sources, *end, *fname;
383 	const char *basename;
384 	char filelist[PATH_MAX + 1];
385 	char *modverdir = getenv("MODVERDIR");
386 
387 	if (!modverdir)
388 		modverdir = ".";
389 
390 	/* Source files for module are in .tmp_versions/modname.mod,
391 	   after the first line. */
392 	if (strrchr(modname, '/'))
393 		basename = strrchr(modname, '/') + 1;
394 	else
395 		basename = modname;
396 	sprintf(filelist, "%s/%.*s.mod", modverdir,
397 		(int) strlen(basename) - 2, basename);
398 
399 	file = grab_file(filelist, &len);
400 	if (!file) {
401 		warn("could not find versions for %s\n", filelist);
402 		return;
403 	}
404 
405 	sources = strchr(file, '\n');
406 	if (!sources) {
407 		warn("malformed versions file for %s\n", modname);
408 		goto release;
409 	}
410 
411 	sources++;
412 	end = strchr(sources, '\n');
413 	if (!end) {
414 		warn("bad ending versions file for %s\n", modname);
415 		goto release;
416 	}
417 	*end = '\0';
418 
419 	md4_init(&md);
420 	while ((fname = strsep(&sources, " ")) != NULL) {
421 		if (!*fname)
422 			continue;
423 		if (!parse_source_files(fname, &md))
424 			goto release;
425 	}
426 
427 	md4_final_ascii(&md, sum, sumlen);
428 release:
429 	release_file(file, len);
430 }
431 
432 static void write_version(const char *filename, const char *sum,
433 			  unsigned long offset)
434 {
435 	int fd;
436 
437 	fd = open(filename, O_RDWR);
438 	if (fd < 0) {
439 		warn("changing sum in %s failed: %s\n",
440 			filename, strerror(errno));
441 		return;
442 	}
443 
444 	if (lseek(fd, offset, SEEK_SET) == (off_t)-1) {
445 		warn("changing sum in %s:%lu failed: %s\n",
446 			filename, offset, strerror(errno));
447 		goto out;
448 	}
449 
450 	if (write(fd, sum, strlen(sum)+1) != strlen(sum)+1) {
451 		warn("writing sum in %s failed: %s\n",
452 			filename, strerror(errno));
453 		goto out;
454 	}
455 out:
456 	close(fd);
457 }
458 
459 static int strip_rcs_crap(char *version)
460 {
461 	unsigned int len, full_len;
462 
463 	if (strncmp(version, "$Revision", strlen("$Revision")) != 0)
464 		return 0;
465 
466 	/* Space for version string follows. */
467 	full_len = strlen(version) + strlen(version + strlen(version) + 1) + 2;
468 
469 	/* Move string to start with version number: prefix will be
470 	 * $Revision$ or $Revision: */
471 	len = strlen("$Revision");
472 	if (version[len] == ':' || version[len] == '$')
473 		len++;
474 	while (isspace(version[len]))
475 		len++;
476 	memmove(version, version+len, full_len-len);
477 	full_len -= len;
478 
479 	/* Preserve up to next whitespace. */
480 	len = 0;
481 	while (version[len] && !isspace(version[len]))
482 		len++;
483 	memmove(version + len, version + strlen(version),
484 		full_len - strlen(version));
485 	return 1;
486 }
487 
488 /* Clean up RCS-style version numbers. */
489 void maybe_frob_rcs_version(const char *modfilename,
490 			    char *version,
491 			    void *modinfo,
492 			    unsigned long version_offset)
493 {
494 	if (strip_rcs_crap(version))
495 		write_version(modfilename, version, version_offset);
496 }
497