~drizzle-trunk/drizzle/development

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
/* Copyright (C) 2000-2006 MySQL AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/* password checking routines */
/*****************************************************************************
  The main idea is that no password are sent between client & server on
  connection and that no password are saved in mysql in a decodable form.

  On connection a random string is generated and sent to the client.
  The client generates a new string with a random generator inited with
  the hash values from the password and the sent string.
  This 'check' string is sent to the server where it is compared with
  a string generated from the stored hash_value of the password and the
  random string.

  The password is saved (in user.password) by using the PASSWORD() function in
  mysql.

  This is .c file because it's used in libmysqlclient, which is entirely in C.
  (we need it to be portable to a variety of systems).
  Example:
    update user set password=PASSWORD("hello") where user="test"
  This saves a hashed number as a string in the password field.

  The new authentication is performed in following manner:

  SERVER:  public_seed=create_random_string()
           send(public_seed)

  CLIENT:  recv(public_seed)
           hash_stage1=sha1("password")
           hash_stage2=sha1(hash_stage1)
           reply=xor(hash_stage1, sha1(public_seed,hash_stage2)

           // this three steps are done in scramble() 

           send(reply)

     
  SERVER:  recv(reply)
           hash_stage1=xor(reply, sha1(public_seed,hash_stage2))
           candidate_hash2=sha1(hash_stage1)
           check(candidate_hash2==hash_stage2)

           // this three steps are done in check_scramble()

*****************************************************************************/

#include <my_global.h>
#include <my_sys.h>
#include <m_string.h>
#include <sha1.h>
#include "drizzle.h"

/************ MySQL 3.23-4.0 authentication routines: untouched ***********/

/*
  New (MySQL 3.21+) random generation structure initialization
  SYNOPSIS
    randominit()
    rand_st    OUT  Structure to initialize
    seed1      IN   First initialization parameter
    seed2      IN   Second initialization parameter
*/

void randominit(struct rand_struct *rand_st, ulong seed1, ulong seed2)
{                                               /* For mysql 3.21.# */
#ifdef HAVE_purify
  bzero((char*) rand_st,sizeof(*rand_st));      /* Avoid UMC varnings */
#endif
  rand_st->max_value= 0x3FFFFFFFL;
  rand_st->max_value_dbl=(double) rand_st->max_value;
  rand_st->seed1=seed1%rand_st->max_value ;
  rand_st->seed2=seed2%rand_st->max_value;
}


/*
    Generate random number.
  SYNOPSIS
    my_rnd()
    rand_st    INOUT  Structure used for number generation
  RETURN VALUE
    generated pseudo random number
*/

double my_rnd(struct rand_struct *rand_st)
{
  rand_st->seed1=(rand_st->seed1*3+rand_st->seed2) % rand_st->max_value;
  rand_st->seed2=(rand_st->seed1+rand_st->seed2+33) % rand_st->max_value;
  return (((double) rand_st->seed1)/rand_st->max_value_dbl);
}


/*
    Generate binary hash from raw text string 
    Used for Pre-4.1 password handling
  SYNOPSIS
    hash_password()
    result       OUT store hash in this location
    password     IN  plain text password to build hash
    password_len IN  password length (password may be not null-terminated)
*/

void hash_password(ulong *result, const char *password, uint password_len)
{
  register ulong nr=1345345333L, add=7, nr2=0x12345671L;
  ulong tmp;
  const char *password_end= password + password_len;
  for (; password < password_end; password++)
  {
    if (*password == ' ' || *password == '\t')
      continue;                                 /* skip space in password */
    tmp= (ulong) (uchar) *password;
    nr^= (((nr & 63)+add)*tmp)+ (nr << 8);
    nr2+=(nr2 << 8) ^ nr;
    add+=tmp;
  }
  result[0]=nr & (((ulong) 1L << 31) -1L); /* Don't use sign bit (str2int) */;
  result[1]=nr2 & (((ulong) 1L << 31) -1L);
}


/*
    Create password to be stored in user database from raw string
    Used for pre-4.1 password handling
  SYNOPSIS
    make_scrambled_password_323()
    to        OUT store scrambled password here
    password  IN  user-supplied password
*/

void make_scrambled_password_323(char *to, const char *password)
{
  ulong hash_res[2];
  hash_password(hash_res, password, (uint) strlen(password));
  sprintf(to, "%08lx%08lx", hash_res[0], hash_res[1]);
}


/*
    Scramble string with password.
    Used in pre 4.1 authentication phase.
  SYNOPSIS
    scramble_323()
    to       OUT Store scrambled message here. Buffer must be at least
                 SCRAMBLE_LENGTH_323+1 bytes long
    message  IN  Message to scramble. Message must be at least
                 SRAMBLE_LENGTH_323 bytes long.
    password IN  Password to use while scrambling
*/

void scramble_323(char *to, const char *message, const char *password)
{
  struct rand_struct rand_st;
  ulong hash_pass[2], hash_message[2];

  if (password && password[0])
  {
    char extra, *to_start=to;
    const char *message_end= message + SCRAMBLE_LENGTH_323;
    hash_password(hash_pass,password, (uint) strlen(password));
    hash_password(hash_message, message, SCRAMBLE_LENGTH_323);
    randominit(&rand_st,hash_pass[0] ^ hash_message[0],
               hash_pass[1] ^ hash_message[1]);
    for (; message < message_end; message++)
      *to++= (char) (floor(my_rnd(&rand_st)*31)+64);
    extra=(char) (floor(my_rnd(&rand_st)*31));
    while (to_start != to)
      *(to_start++)^=extra;
  }
  *to= 0;
}


/*
    Check scrambled message
    Used in pre 4.1 password handling
  SYNOPSIS
    check_scramble_323()
    scrambled  scrambled message to check.
    message    original random message which was used for scrambling; must
               be exactly SCRAMBLED_LENGTH_323 bytes long and
               NULL-terminated.
    hash_pass  password which should be used for scrambling
    All params are IN.

  RETURN VALUE
    0 - password correct
   !0 - password invalid
*/

my_bool
check_scramble_323(const char *scrambled, const char *message,
                   ulong *hash_pass)
{
  struct rand_struct rand_st;
  ulong hash_message[2];
  char buff[16],*to,extra;                      /* Big enough for check */
  const char *pos;

  hash_password(hash_message, message, SCRAMBLE_LENGTH_323);
  randominit(&rand_st,hash_pass[0] ^ hash_message[0],
             hash_pass[1] ^ hash_message[1]);
  to=buff;
  DBUG_ASSERT(sizeof(buff) > SCRAMBLE_LENGTH_323);
  for (pos=scrambled ; *pos && to < buff+sizeof(buff) ; pos++)
    *to++=(char) (floor(my_rnd(&rand_st)*31)+64);
  if (pos-scrambled != SCRAMBLE_LENGTH_323)
    return 1;
  extra=(char) (floor(my_rnd(&rand_st)*31));
  to=buff;
  while (*scrambled)
  {
    if (*scrambled++ != (char) (*to++ ^ extra))
      return 1;                                 /* Wrong password */
  }
  return 0;
}

static inline uint8 char_val(uint8 X)
{
  return (uint) (X >= '0' && X <= '9' ? X-'0' :
      X >= 'A' && X <= 'Z' ? X-'A'+10 : X-'a'+10);
}


/*
    Convert password from hex string (as stored in mysql.user) to binary form.
  SYNOPSIS
    get_salt_from_password_323()
    res       OUT store salt here 
    password  IN  password string as stored in mysql.user
  NOTE
    This function does not have length check for passwords. It will just crash
    Password hashes in old format must have length divisible by 8
*/

void get_salt_from_password_323(ulong *res, const char *password)
{
  res[0]= res[1]= 0;
  if (password)
  {
    while (*password)
    {
      ulong val=0;
      uint i;
      for (i=0 ; i < 8 ; i++)
        val=(val << 4)+char_val(*password++);
      *res++=val;
    }
  }
}


/*
    Convert scrambled password from binary form to asciiz hex string.
  SYNOPSIS
    make_password_from_salt_323()
    to    OUT store resulting string password here, at least 17 bytes 
    salt  IN  password in salt format, 2 ulongs 
*/

void make_password_from_salt_323(char *to, const ulong *salt)
{
  sprintf(to,"%08lx%08lx", salt[0], salt[1]);
}


/*
     **************** MySQL 4.1.1 authentication routines *************
*/

/*
    Generate string of printable random characters of requested length
  SYNOPSIS
    create_random_string()
    to       OUT   buffer for generation; must be at least length+1 bytes
                   long; result string is always null-terminated
    length   IN    how many random characters to put in buffer
    rand_st  INOUT structure used for number generation
*/

void create_random_string(char *to, uint length, struct rand_struct *rand_st)
{
  char *end= to + length;
  /* Use pointer arithmetics as it is faster way to do so. */
  for (; to < end; to++)
    *to= (char) (my_rnd(rand_st)*94+33);
  *to= '\0';
}


/* Character to use as version identifier for version 4.1 */

#define PVERSION41_CHAR '*'


/*
    Convert given octet sequence to asciiz string of hex characters;
    str..str+len and 'to' may not overlap.
  SYNOPSIS
    octet2hex()
    buf       OUT output buffer. Must be at least 2*len+1 bytes
    str, len  IN  the beginning and the length of the input string

  RETURN
    buf+len*2
*/

char *octet2hex(char *to, const char *str, uint len)
{
  const char *str_end= str + len; 
  for (; str != str_end; ++str)
  {
    *to++= _dig_vec_upper[((uchar) *str) >> 4];
    *to++= _dig_vec_upper[((uchar) *str) & 0x0F];
  }
  *to= '\0';
  return to;
}


/*
    Convert given asciiz string of hex (0..9 a..f) characters to octet
    sequence.
  SYNOPSIS
    hex2octet()
    to        OUT buffer to place result; must be at least len/2 bytes
    str, len  IN  begin, length for character string; str and to may not
                  overlap; len % 2 == 0
*/ 

static void
hex2octet(uint8 *to, const char *str, uint len)
{
  const char *str_end= str + len;
  while (str < str_end)
  {
    register char tmp= char_val(*str++);
    *to++= (tmp << 4) | char_val(*str++);
  }
}


/*
    Encrypt/Decrypt function used for password encryption in authentication.
    Simple XOR is used here but it is OK as we crypt random strings. Note,
    that XOR(s1, XOR(s1, s2)) == s2, XOR(s1, s2) == XOR(s2, s1)
  SYNOPSIS
    my_crypt()
    to      OUT buffer to hold crypted string; must be at least len bytes
                long; to and s1 (or s2) may be the same.
    s1, s2  IN  input strings (of equal length)
    len     IN  length of s1 and s2
*/

static void
my_crypt(char *to, const uchar *s1, const uchar *s2, uint len)
{
  const uint8 *s1_end= s1 + len;
  while (s1 < s1_end)
    *to++= *s1++ ^ *s2++;
}


/*
    MySQL 4.1.1 password hashing: SHA conversion (see RFC 2289, 3174) twice
    applied to the password string, and then produced octet sequence is
    converted to hex string.
    The result of this function is used as return value from PASSWORD() and
    is stored in the database.
  SYNOPSIS
    make_scrambled_password()
    buf       OUT buffer of size 2*SHA1_HASH_SIZE + 2 to store hex string
    password  IN  NULL-terminated password string
*/

void
make_scrambled_password(char *to, const char *password)
{
  SHA1_CONTEXT sha1_context;
  uint8 hash_stage2[SHA1_HASH_SIZE];

  mysql_sha1_reset(&sha1_context);
  /* stage 1: hash password */
  mysql_sha1_input(&sha1_context, (uint8 *) password, (uint) strlen(password));
  mysql_sha1_result(&sha1_context, (uint8 *) to);
  /* stage 2: hash stage1 output */
  mysql_sha1_reset(&sha1_context);
  mysql_sha1_input(&sha1_context, (uint8 *) to, SHA1_HASH_SIZE);
  /* separate buffer is used to pass 'to' in octet2hex */
  mysql_sha1_result(&sha1_context, hash_stage2);
  /* convert hash_stage2 to hex string */
  *to++= PVERSION41_CHAR;
  octet2hex(to, (const char*) hash_stage2, SHA1_HASH_SIZE);
}
  

/*
    Produce an obscure octet sequence from password and random
    string, recieved from the server. This sequence corresponds to the
    password, but password can not be easily restored from it. The sequence
    is then sent to the server for validation. Trailing zero is not stored
    in the buf as it is not needed.
    This function is used by client to create authenticated reply to the
    server's greeting.
  SYNOPSIS
    scramble()
    buf       OUT store scrambled string here. The buf must be at least 
                  SHA1_HASH_SIZE bytes long. 
    message   IN  random message, must be exactly SCRAMBLE_LENGTH long and 
                  NULL-terminated.
    password  IN  users' password 
*/

void
scramble(char *to, const char *message, const char *password)
{
  SHA1_CONTEXT sha1_context;
  uint8 hash_stage1[SHA1_HASH_SIZE];
  uint8 hash_stage2[SHA1_HASH_SIZE];

  mysql_sha1_reset(&sha1_context);
  /* stage 1: hash password */
  mysql_sha1_input(&sha1_context, (uint8 *) password, (uint) strlen(password));
  mysql_sha1_result(&sha1_context, hash_stage1);
  /* stage 2: hash stage 1; note that hash_stage2 is stored in the database */
  mysql_sha1_reset(&sha1_context);
  mysql_sha1_input(&sha1_context, hash_stage1, SHA1_HASH_SIZE);
  mysql_sha1_result(&sha1_context, hash_stage2);
  /* create crypt string as sha1(message, hash_stage2) */;
  mysql_sha1_reset(&sha1_context);
  mysql_sha1_input(&sha1_context, (const uint8 *) message, SCRAMBLE_LENGTH);
  mysql_sha1_input(&sha1_context, hash_stage2, SHA1_HASH_SIZE);
  /* xor allows 'from' and 'to' overlap: lets take advantage of it */
  mysql_sha1_result(&sha1_context, (uint8 *) to);
  my_crypt(to, (const uchar *) to, hash_stage1, SCRAMBLE_LENGTH);
}


/*
    Check that scrambled message corresponds to the password; the function
    is used by server to check that recieved reply is authentic.
    This function does not check lengths of given strings: message must be
    null-terminated, reply and hash_stage2 must be at least SHA1_HASH_SIZE
    long (if not, something fishy is going on).
  SYNOPSIS
    check_scramble()
    scramble     clients' reply, presumably produced by scramble()
    message      original random string, previously sent to client
                 (presumably second argument of scramble()), must be 
                 exactly SCRAMBLE_LENGTH long and NULL-terminated.
    hash_stage2  hex2octet-decoded database entry
    All params are IN.

  RETURN VALUE
    0  password is correct
    !0  password is invalid
*/

my_bool
check_scramble(const char *scramble_arg, const char *message,
               const uint8 *hash_stage2)
{
  SHA1_CONTEXT sha1_context;
  uint8 buf[SHA1_HASH_SIZE];
  uint8 hash_stage2_reassured[SHA1_HASH_SIZE];

  mysql_sha1_reset(&sha1_context);
  /* create key to encrypt scramble */
  mysql_sha1_input(&sha1_context, (const uint8 *) message, SCRAMBLE_LENGTH);
  mysql_sha1_input(&sha1_context, hash_stage2, SHA1_HASH_SIZE);
  mysql_sha1_result(&sha1_context, buf);
  /* encrypt scramble */
    my_crypt((char *) buf, buf, (const uchar *) scramble_arg, SCRAMBLE_LENGTH);
  /* now buf supposedly contains hash_stage1: so we can get hash_stage2 */
  mysql_sha1_reset(&sha1_context);
  mysql_sha1_input(&sha1_context, buf, SHA1_HASH_SIZE);
  mysql_sha1_result(&sha1_context, hash_stage2_reassured);
  return memcmp(hash_stage2, hash_stage2_reassured, SHA1_HASH_SIZE);
}


/*
  Convert scrambled password from asciiz hex string to binary form.

  SYNOPSIS
    get_salt_from_password()
    res       OUT buf to hold password. Must be at least SHA1_HASH_SIZE
                  bytes long.
    password  IN  4.1.1 version value of user.password
*/
    
void get_salt_from_password(uint8 *hash_stage2, const char *password)
{
  hex2octet(hash_stage2, password+1 /* skip '*' */, SHA1_HASH_SIZE * 2);
}

/*
    Convert scrambled password from binary form to asciiz hex string.
  SYNOPSIS
    make_password_from_salt()
    to    OUT store resulting string here, 2*SHA1_HASH_SIZE+2 bytes 
    salt  IN  password in salt format
*/

void make_password_from_salt(char *to, const uint8 *hash_stage2)
{
  *to++= PVERSION41_CHAR;
  octet2hex(to, (const char*) hash_stage2, SHA1_HASH_SIZE);
}