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sumversion.c
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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 ([email protected]) 2002
25  * Copyright (c) Cryptoapi developers.
26  * Copyright (c) 2002 David S. Miller ([email protected])
27  * Copyright (c) 2002 James Morris <[email protected]>
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 {
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  sprintf(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 }