xref: /linux/scripts/mod/sumversion.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 <limits.h>
11 #include "modpost.h"
12 
13 /*
14  * Stolen form Cryptographic API.
15  *
16  * MD4 Message Digest Algorithm (RFC1320).
17  *
18  * Implementation derived from Andrew Tridgell and Steve French's
19  * CIFS MD4 implementation, and the cryptoapi implementation
20  * originally based on the public domain implementation written
21  * by Colin Plumb in 1993.
22  *
23  * Copyright (c) Andrew Tridgell 1997-1998.
24  * Modified by Steve French (sfrench@us.ibm.com) 2002
25  * Copyright (c) Cryptoapi developers.
26  * Copyright (c) 2002 David S. Miller (davem@redhat.com)
27  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
28  *
29  * This program is free software; you can redistribute it and/or modify
30  * it under the terms of the GNU General Public License as published by
31  * the Free Software Foundation; either version 2 of the License, or
32  * (at your option) any later version.
33  *
34  */
35 #define MD4_DIGEST_SIZE		16
36 #define MD4_HMAC_BLOCK_SIZE	64
37 #define MD4_BLOCK_WORDS		16
38 #define MD4_HASH_WORDS		4
39 
40 struct md4_ctx {
41 	uint32_t hash[MD4_HASH_WORDS];
42 	uint32_t block[MD4_BLOCK_WORDS];
43 	uint64_t byte_count;
44 };
45 
46 static inline uint32_t lshift(uint32_t x, unsigned int s)
47 {
48 	x &= 0xFFFFFFFF;
49 	return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
50 }
51 
52 static inline uint32_t F(uint32_t x, uint32_t y, uint32_t z)
53 {
54 	return (x & y) | ((~x) & z);
55 }
56 
57 static inline uint32_t G(uint32_t x, uint32_t y, uint32_t z)
58 {
59 	return (x & y) | (x & z) | (y & z);
60 }
61 
62 static inline uint32_t H(uint32_t x, uint32_t y, uint32_t z)
63 {
64 	return x ^ y ^ z;
65 }
66 
67 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s))
68 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (uint32_t)0x5A827999,s))
69 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (uint32_t)0x6ED9EBA1,s))
70 
71 /* XXX: this stuff can be optimized */
72 static inline void le32_to_cpu_array(uint32_t *buf, unsigned int words)
73 {
74 	while (words--) {
75 		*buf = ntohl(*buf);
76 		buf++;
77 	}
78 }
79 
80 static inline void cpu_to_le32_array(uint32_t *buf, unsigned int words)
81 {
82 	while (words--) {
83 		*buf = htonl(*buf);
84 		buf++;
85 	}
86 }
87 
88 static void md4_transform(uint32_t *hash, uint32_t const *in)
89 {
90 	uint32_t a, b, c, d;
91 
92 	a = hash[0];
93 	b = hash[1];
94 	c = hash[2];
95 	d = hash[3];
96 
97 	ROUND1(a, b, c, d, in[0], 3);
98 	ROUND1(d, a, b, c, in[1], 7);
99 	ROUND1(c, d, a, b, in[2], 11);
100 	ROUND1(b, c, d, a, in[3], 19);
101 	ROUND1(a, b, c, d, in[4], 3);
102 	ROUND1(d, a, b, c, in[5], 7);
103 	ROUND1(c, d, a, b, in[6], 11);
104 	ROUND1(b, c, d, a, in[7], 19);
105 	ROUND1(a, b, c, d, in[8], 3);
106 	ROUND1(d, a, b, c, in[9], 7);
107 	ROUND1(c, d, a, b, in[10], 11);
108 	ROUND1(b, c, d, a, in[11], 19);
109 	ROUND1(a, b, c, d, in[12], 3);
110 	ROUND1(d, a, b, c, in[13], 7);
111 	ROUND1(c, d, a, b, in[14], 11);
112 	ROUND1(b, c, d, a, in[15], 19);
113 
114 	ROUND2(a, b, c, d,in[ 0], 3);
115 	ROUND2(d, a, b, c, in[4], 5);
116 	ROUND2(c, d, a, b, in[8], 9);
117 	ROUND2(b, c, d, a, in[12], 13);
118 	ROUND2(a, b, c, d, in[1], 3);
119 	ROUND2(d, a, b, c, in[5], 5);
120 	ROUND2(c, d, a, b, in[9], 9);
121 	ROUND2(b, c, d, a, in[13], 13);
122 	ROUND2(a, b, c, d, in[2], 3);
123 	ROUND2(d, a, b, c, in[6], 5);
124 	ROUND2(c, d, a, b, in[10], 9);
125 	ROUND2(b, c, d, a, in[14], 13);
126 	ROUND2(a, b, c, d, in[3], 3);
127 	ROUND2(d, a, b, c, in[7], 5);
128 	ROUND2(c, d, a, b, in[11], 9);
129 	ROUND2(b, c, d, a, in[15], 13);
130 
131 	ROUND3(a, b, c, d,in[ 0], 3);
132 	ROUND3(d, a, b, c, in[8], 9);
133 	ROUND3(c, d, a, b, in[4], 11);
134 	ROUND3(b, c, d, a, in[12], 15);
135 	ROUND3(a, b, c, d, in[2], 3);
136 	ROUND3(d, a, b, c, in[10], 9);
137 	ROUND3(c, d, a, b, in[6], 11);
138 	ROUND3(b, c, d, a, in[14], 15);
139 	ROUND3(a, b, c, d, in[1], 3);
140 	ROUND3(d, a, b, c, in[9], 9);
141 	ROUND3(c, d, a, b, in[5], 11);
142 	ROUND3(b, c, d, a, in[13], 15);
143 	ROUND3(a, b, c, d, in[3], 3);
144 	ROUND3(d, a, b, c, in[11], 9);
145 	ROUND3(c, d, a, b, in[7], 11);
146 	ROUND3(b, c, d, a, in[15], 15);
147 
148 	hash[0] += a;
149 	hash[1] += b;
150 	hash[2] += c;
151 	hash[3] += d;
152 }
153 
154 static inline void md4_transform_helper(struct md4_ctx *ctx)
155 {
156 	le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(uint32_t));
157 	md4_transform(ctx->hash, ctx->block);
158 }
159 
160 static void md4_init(struct md4_ctx *mctx)
161 {
162 	mctx->hash[0] = 0x67452301;
163 	mctx->hash[1] = 0xefcdab89;
164 	mctx->hash[2] = 0x98badcfe;
165 	mctx->hash[3] = 0x10325476;
166 	mctx->byte_count = 0;
167 }
168 
169 static void md4_update(struct md4_ctx *mctx,
170 		       const unsigned char *data, unsigned int len)
171 {
172 	const uint32_t avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f);
173 
174 	mctx->byte_count += len;
175 
176 	if (avail > len) {
177 		memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
178 		       data, len);
179 		return;
180 	}
181 
182 	memcpy((char *)mctx->block + (sizeof(mctx->block) - avail),
183 	       data, avail);
184 
185 	md4_transform_helper(mctx);
186 	data += avail;
187 	len -= avail;
188 
189 	while (len >= sizeof(mctx->block)) {
190 		memcpy(mctx->block, data, sizeof(mctx->block));
191 		md4_transform_helper(mctx);
192 		data += sizeof(mctx->block);
193 		len -= sizeof(mctx->block);
194 	}
195 
196 	memcpy(mctx->block, data, len);
197 }
198 
199 static void md4_final_ascii(struct md4_ctx *mctx, char *out, unsigned int len)
200 {
201 	const unsigned int offset = mctx->byte_count & 0x3f;
202 	char *p = (char *)mctx->block + offset;
203 	int padding = 56 - (offset + 1);
204 
205 	*p++ = 0x80;
206 	if (padding < 0) {
207 		memset(p, 0x00, padding + sizeof (uint64_t));
208 		md4_transform_helper(mctx);
209 		p = (char *)mctx->block;
210 		padding = 56;
211 	}
212 
213 	memset(p, 0, padding);
214 	mctx->block[14] = mctx->byte_count << 3;
215 	mctx->block[15] = mctx->byte_count >> 29;
216 	le32_to_cpu_array(mctx->block, (sizeof(mctx->block) -
217 			  sizeof(uint64_t)) / sizeof(uint32_t));
218 	md4_transform(mctx->hash, mctx->block);
219 	cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(uint32_t));
220 
221 	snprintf(out, len, "%08X%08X%08X%08X",
222 		 mctx->hash[0], mctx->hash[1], mctx->hash[2], mctx->hash[3]);
223 }
224 
225 static inline void add_char(unsigned char c, struct md4_ctx *md)
226 {
227 	md4_update(md, &c, 1);
228 }
229 
230 static int parse_string(const char *file, unsigned long len,
231 			struct md4_ctx *md)
232 {
233 	unsigned long i;
234 
235 	add_char(file[0], md);
236 	for (i = 1; i < len; i++) {
237 		add_char(file[i], md);
238 		if (file[i] == '"' && file[i-1] != '\\')
239 			break;
240 	}
241 	return i;
242 }
243 
244 static int parse_comment(const char *file, unsigned long len)
245 {
246 	unsigned long i;
247 
248 	for (i = 2; i < len; i++) {
249 		if (file[i-1] == '*' && file[i] == '/')
250 			break;
251 	}
252 	return i;
253 }
254 
255 /* FIXME: Handle .s files differently (eg. # starts comments) --RR */
256 static int parse_file(const char *fname, struct md4_ctx *md)
257 {
258 	char *file;
259 	unsigned long i, len;
260 
261 	file = grab_file(fname, &len);
262 	if (!file)
263 		return 0;
264 
265 	for (i = 0; i < len; i++) {
266 		/* Collapse and ignore \ and CR. */
267 		if (file[i] == '\\' && (i+1 < len) && file[i+1] == '\n') {
268 			i++;
269 			continue;
270 		}
271 
272 		/* Ignore whitespace */
273 		if (isspace(file[i]))
274 			continue;
275 
276 		/* Handle strings as whole units */
277 		if (file[i] == '"') {
278 			i += parse_string(file+i, len - i, md);
279 			continue;
280 		}
281 
282 		/* Comments: ignore */
283 		if (file[i] == '/' && file[i+1] == '*') {
284 			i += parse_comment(file+i, len - i);
285 			continue;
286 		}
287 
288 		add_char(file[i], md);
289 	}
290 	release_file(file, len);
291 	return 1;
292 }
293 /* Check whether the file is a static library or not */
294 static int is_static_library(const char *objfile)
295 {
296 	int len = strlen(objfile);
297 	if (objfile[len - 2] == '.' && objfile[len - 1] == 'a')
298 		return 1;
299 	else
300 		return 0;
301 }
302 
303 /* We have dir/file.o.  Open dir/.file.o.cmd, look for source_ and deps_ line
304  * to figure out source files. */
305 static int parse_source_files(const char *objfile, struct md4_ctx *md)
306 {
307 	char *cmd, *file, *line, *dir;
308 	const char *base;
309 	unsigned long flen, pos = 0;
310 	int dirlen, ret = 0, check_files = 0;
311 
312 	cmd = NOFAIL(malloc(strlen(objfile) + sizeof("..cmd")));
313 
314 	base = strrchr(objfile, '/');
315 	if (base) {
316 		base++;
317 		dirlen = base - objfile;
318 		sprintf(cmd, "%.*s.%s.cmd", dirlen, objfile, base);
319 	} else {
320 		dirlen = 0;
321 		sprintf(cmd, ".%s.cmd", objfile);
322 	}
323 	dir = NOFAIL(malloc(dirlen + 1));
324 	strncpy(dir, objfile, dirlen);
325 	dir[dirlen] = '\0';
326 
327 	file = grab_file(cmd, &flen);
328 	if (!file) {
329 		warn("could not find %s for %s\n", cmd, objfile);
330 		goto out;
331 	}
332 
333 	/* There will be a line like so:
334 		deps_drivers/net/dummy.o := \
335 		  drivers/net/dummy.c \
336 		    $(wildcard include/config/net/fastroute.h) \
337 		  include/linux/module.h \
338 
339 	   Sum all files in the same dir or subdirs.
340 	*/
341 	while ((line = get_next_line(&pos, file, flen)) != NULL) {
342 		char* p = line;
343 
344 		if (strncmp(line, "source_", sizeof("source_")-1) == 0) {
345 			p = strrchr(line, ' ');
346 			if (!p) {
347 				warn("malformed line: %s\n", line);
348 				goto out_file;
349 			}
350 			p++;
351 			if (!parse_file(p, md)) {
352 				warn("could not open %s: %s\n",
353 				     p, strerror(errno));
354 				goto out_file;
355 			}
356 			continue;
357 		}
358 		if (strncmp(line, "deps_", sizeof("deps_")-1) == 0) {
359 			check_files = 1;
360 			continue;
361 		}
362 		if (!check_files)
363 			continue;
364 
365 		/* Continue until line does not end with '\' */
366 		if ( *(p + strlen(p)-1) != '\\')
367 			break;
368 		/* Terminate line at first space, to get rid of final ' \' */
369 		while (*p) {
370 			if (isspace(*p)) {
371 				*p = '\0';
372 				break;
373 			}
374 			p++;
375 		}
376 
377 		/* Check if this file is in same dir as objfile */
378 		if ((strstr(line, dir)+strlen(dir)-1) == strrchr(line, '/')) {
379 			if (!parse_file(line, md)) {
380 				warn("could not open %s: %s\n",
381 				     line, strerror(errno));
382 				goto out_file;
383 			}
384 
385 		}
386 
387 	}
388 
389 	/* Everyone parsed OK */
390 	ret = 1;
391 out_file:
392 	release_file(file, flen);
393 out:
394 	free(dir);
395 	free(cmd);
396 	return ret;
397 }
398 
399 /* Calc and record src checksum. */
400 void get_src_version(const char *modname, char sum[], unsigned sumlen)
401 {
402 	void *file;
403 	unsigned long len;
404 	struct md4_ctx md;
405 	char *sources, *end, *fname;
406 	const char *basename;
407 	char filelist[PATH_MAX + 1];
408 	char *modverdir = getenv("MODVERDIR");
409 
410 	if (!modverdir)
411 		modverdir = ".";
412 
413 	/* Source files for module are in .tmp_versions/modname.mod,
414 	   after the first line. */
415 	if (strrchr(modname, '/'))
416 		basename = strrchr(modname, '/') + 1;
417 	else
418 		basename = modname;
419 	snprintf(filelist, sizeof(filelist), "%s/%.*s.mod", modverdir,
420 		(int) strlen(basename) - 2, basename);
421 
422 	file = grab_file(filelist, &len);
423 	if (!file)
424 		/* not a module or .mod file missing - ignore */
425 		return;
426 
427 	sources = strchr(file, '\n');
428 	if (!sources) {
429 		warn("malformed versions file for %s\n", modname);
430 		goto release;
431 	}
432 
433 	sources++;
434 	end = strchr(sources, '\n');
435 	if (!end) {
436 		warn("bad ending versions file for %s\n", modname);
437 		goto release;
438 	}
439 	*end = '\0';
440 
441 	md4_init(&md);
442 	while ((fname = strsep(&sources, " ")) != NULL) {
443 		if (!*fname)
444 			continue;
445 		if (!(is_static_library(fname)) &&
446 				!parse_source_files(fname, &md))
447 			goto release;
448 	}
449 
450 	md4_final_ascii(&md, sum, sumlen);
451 release:
452 	release_file(file, len);
453 }
454 
455 static void write_version(const char *filename, const char *sum,
456 			  unsigned long offset)
457 {
458 	int fd;
459 
460 	fd = open(filename, O_RDWR);
461 	if (fd < 0) {
462 		warn("changing sum in %s failed: %s\n",
463 			filename, strerror(errno));
464 		return;
465 	}
466 
467 	if (lseek(fd, offset, SEEK_SET) == (off_t)-1) {
468 		warn("changing sum in %s:%lu failed: %s\n",
469 			filename, offset, strerror(errno));
470 		goto out;
471 	}
472 
473 	if (write(fd, sum, strlen(sum)+1) != strlen(sum)+1) {
474 		warn("writing sum in %s failed: %s\n",
475 			filename, strerror(errno));
476 		goto out;
477 	}
478 out:
479 	close(fd);
480 }
481 
482 static int strip_rcs_crap(char *version)
483 {
484 	unsigned int len, full_len;
485 
486 	if (strncmp(version, "$Revision", strlen("$Revision")) != 0)
487 		return 0;
488 
489 	/* Space for version string follows. */
490 	full_len = strlen(version) + strlen(version + strlen(version) + 1) + 2;
491 
492 	/* Move string to start with version number: prefix will be
493 	 * $Revision$ or $Revision: */
494 	len = strlen("$Revision");
495 	if (version[len] == ':' || version[len] == '$')
496 		len++;
497 	while (isspace(version[len]))
498 		len++;
499 	memmove(version, version+len, full_len-len);
500 	full_len -= len;
501 
502 	/* Preserve up to next whitespace. */
503 	len = 0;
504 	while (version[len] && !isspace(version[len]))
505 		len++;
506 	memmove(version + len, version + strlen(version),
507 		full_len - strlen(version));
508 	return 1;
509 }
510 
511 /* Clean up RCS-style version numbers. */
512 void maybe_frob_rcs_version(const char *modfilename,
513 			    char *version,
514 			    void *modinfo,
515 			    unsigned long version_offset)
516 {
517 	if (strip_rcs_crap(version))
518 		write_version(modfilename, version, version_offset);
519 }
520