|
1
|
/* |
|
2
|
** Copyright (c) 2009 D. Richard Hipp |
|
3
|
** |
|
4
|
** This program is free software; you can redistribute it and/or |
|
5
|
** modify it under the terms of the Simplified BSD License (also |
|
6
|
** known as the "2-Clause License" or "FreeBSD License".) |
|
7
|
|
|
8
|
** This program is distributed in the hope that it will be useful, |
|
9
|
** but without any warranty; without even the implied warranty of |
|
10
|
** merchantability or fitness for a particular purpose. |
|
11
|
** |
|
12
|
** Author contact information: |
|
13
|
** [email protected] |
|
14
|
** http://www.hwaci.com/drh/ |
|
15
|
** |
|
16
|
******************************************************************************* |
|
17
|
** |
|
18
|
** This file contains code to a simple text-based CAPTCHA. Though easily |
|
19
|
** defeated by a sophisticated attacker, this CAPTCHA does at least make |
|
20
|
** scripting attacks more difficult. |
|
21
|
*/ |
|
22
|
#include "config.h" |
|
23
|
#include <assert.h> |
|
24
|
#include "captcha.h" |
|
25
|
|
|
26
|
#if INTERFACE |
|
27
|
#define CAPTCHA 2 /* Which captcha rendering to use */ |
|
28
|
#endif |
|
29
|
|
|
30
|
/* |
|
31
|
** Convert a hex digit into a value between 0 and 15 |
|
32
|
*/ |
|
33
|
int hex_digit_value(char c){ |
|
34
|
if( c>='0' && c<='9' ){ |
|
35
|
return c - '0'; |
|
36
|
}else if( c>='a' && c<='f' ){ |
|
37
|
return c - 'a' + 10; |
|
38
|
}else if( c>='A' && c<='F' ){ |
|
39
|
return c - 'A' + 10; |
|
40
|
}else{ |
|
41
|
return 0; |
|
42
|
} |
|
43
|
} |
|
44
|
|
|
45
|
#if CAPTCHA==1 |
|
46
|
/* |
|
47
|
** A 4x6 pixel bitmap font for hexadecimal digits |
|
48
|
*/ |
|
49
|
static const unsigned int aFont1[] = { |
|
50
|
0x699996, |
|
51
|
0x262227, |
|
52
|
0x69124f, |
|
53
|
0xf16196, |
|
54
|
0x26af22, |
|
55
|
0xf8e196, |
|
56
|
0x68e996, |
|
57
|
0xf12244, |
|
58
|
0x696996, |
|
59
|
0x699716, |
|
60
|
0x699f99, |
|
61
|
0xe9e99e, |
|
62
|
0x698896, |
|
63
|
0xe9999e, |
|
64
|
0xf8e88f, |
|
65
|
0xf8e888, |
|
66
|
}; |
|
67
|
|
|
68
|
/* |
|
69
|
** Render an 8-character hexadecimal string as ascii art. |
|
70
|
** Space to hold the result is obtained from malloc() and should be freed |
|
71
|
** by the caller. |
|
72
|
*/ |
|
73
|
char *captcha_render(const char *zPw){ |
|
74
|
char *z = fossil_malloc( 9*12*3*strlen(zPw) + 8 ); |
|
75
|
int i, j, k, m; |
|
76
|
|
|
77
|
k = 0; |
|
78
|
for(i=0; i<6; i++){ |
|
79
|
for(j=0; zPw[j]; j++){ |
|
80
|
unsigned char v = hex_digit_value(zPw[j]); |
|
81
|
v = (aFont1[v] >> ((5-i)*4)) & 0xf; |
|
82
|
for(m=8; m>=1; m = m>>1){ |
|
83
|
if( v & m ){ |
|
84
|
z[k++] = 0xe2; |
|
85
|
z[k++] = 0x96; |
|
86
|
z[k++] = 0x88; |
|
87
|
z[k++] = 0xe2; |
|
88
|
z[k++] = 0x96; |
|
89
|
z[k++] = 0x88; |
|
90
|
}else{ |
|
91
|
z[k++] = ' '; |
|
92
|
z[k++] = ' '; |
|
93
|
} |
|
94
|
} |
|
95
|
z[k++] = ' '; |
|
96
|
z[k++] = ' '; |
|
97
|
} |
|
98
|
z[k++] = '\n'; |
|
99
|
} |
|
100
|
z[k] = 0; |
|
101
|
return z; |
|
102
|
} |
|
103
|
#endif /* CAPTCHA==1 */ |
|
104
|
|
|
105
|
#if CAPTCHA==2 |
|
106
|
/* |
|
107
|
** A 5x7 pixel bitmap font for hexadecimal digits |
|
108
|
*/ |
|
109
|
static const unsigned char aFont2[] = { |
|
110
|
/* 0 */ 0x0e, 0x13, 0x15, 0x19, 0x11, 0x11, 0x0e, |
|
111
|
/* 1 */ 0x02, 0x06, 0x0A, 0x02, 0x02, 0x02, 0x02, |
|
112
|
/* 2 */ 0x0e, 0x11, 0x01, 0x02, 0x04, 0x08, 0x1f, |
|
113
|
/* 3 */ 0x0e, 0x11, 0x01, 0x06, 0x01, 0x11, 0x0e, |
|
114
|
/* 4 */ 0x02, 0x06, 0x0A, 0x12, 0x1f, 0x02, 0x02, |
|
115
|
/* 5 */ 0x1f, 0x10, 0x1e, 0x01, 0x01, 0x11, 0x0e, |
|
116
|
/* 6 */ 0x0e, 0x11, 0x10, 0x1e, 0x11, 0x11, 0x0e, |
|
117
|
/* 7 */ 0x1f, 0x01, 0x02, 0x04, 0x08, 0x08, 0x08, |
|
118
|
/* 8 */ 0x0e, 0x11, 0x11, 0x0e, 0x11, 0x11, 0x0e, |
|
119
|
/* 9 */ 0x0e, 0x11, 0x11, 0x0f, 0x01, 0x11, 0x0e, |
|
120
|
/* A */ 0x0e, 0x11, 0x11, 0x11, 0x1f, 0x11, 0x11, |
|
121
|
/* B */ 0x1e, 0x11, 0x11, 0x1e, 0x11, 0x11, 0x1e, |
|
122
|
/* C */ 0x0e, 0x11, 0x10, 0x10, 0x10, 0x11, 0x0e, |
|
123
|
/* D */ 0x1c, 0x12, 0x11, 0x11, 0x11, 0x12, 0x1c, |
|
124
|
/* E */ 0x1f, 0x10, 0x10, 0x1c, 0x10, 0x10, 0x1f, |
|
125
|
/* F */ 0x1f, 0x10, 0x10, 0x1e, 0x10, 0x10, 0x10, |
|
126
|
}; |
|
127
|
|
|
128
|
/* |
|
129
|
** Render an 8-character hexadecimal string as ascii art. |
|
130
|
** Space to hold the result is obtained from malloc() and should be freed |
|
131
|
** by the caller. |
|
132
|
*/ |
|
133
|
char *captcha_render(const char *zPw){ |
|
134
|
char *z = fossil_malloc( 224*strlen(zPw) + 9 ); |
|
135
|
int i, j, k, m; |
|
136
|
|
|
137
|
k = 0; |
|
138
|
for(i=0; i<7; i++){ |
|
139
|
for(j=0; zPw[j]; j++){ |
|
140
|
unsigned char v = hex_digit_value(zPw[j]); |
|
141
|
v = aFont2[v*7+i]; |
|
142
|
for(m=16; m>=1; m = m>>1){ |
|
143
|
if( v & m ){ |
|
144
|
z[k++] = 0xe2; |
|
145
|
z[k++] = 0x96; |
|
146
|
z[k++] = 0x88; |
|
147
|
z[k++] = 0xe2; |
|
148
|
z[k++] = 0x96; |
|
149
|
z[k++] = 0x88; |
|
150
|
}else{ |
|
151
|
z[k++] = 0xe2; |
|
152
|
z[k++] = 0x96; |
|
153
|
z[k++] = 0x91; |
|
154
|
z[k++] = 0xe2; |
|
155
|
z[k++] = 0x96; |
|
156
|
z[k++] = 0x91; |
|
157
|
} |
|
158
|
} |
|
159
|
z[k++] = ' '; |
|
160
|
z[k++] = ' '; |
|
161
|
} |
|
162
|
z[k++] = '\n'; |
|
163
|
} |
|
164
|
z[k] = 0; |
|
165
|
return z; |
|
166
|
} |
|
167
|
#endif /* CAPTCHA==2 */ |
|
168
|
|
|
169
|
|
|
170
|
#if CAPTCHA==3 |
|
171
|
static const char *const azFont3[] = { |
|
172
|
/* 0 */ |
|
173
|
" __ ", |
|
174
|
" / \\ ", |
|
175
|
"| () |", |
|
176
|
" \\__/ ", |
|
177
|
|
|
178
|
/* 1 */ |
|
179
|
" _ ", |
|
180
|
"/ |", |
|
181
|
"| |", |
|
182
|
"|_|", |
|
183
|
|
|
184
|
/* 2 */ |
|
185
|
" ___ ", |
|
186
|
"|_ )", |
|
187
|
" / / ", |
|
188
|
"/___|", |
|
189
|
|
|
190
|
/* 3 */ |
|
191
|
" ____", |
|
192
|
"|__ /", |
|
193
|
" |_ \\", |
|
194
|
"|___/", |
|
195
|
|
|
196
|
/* 4 */ |
|
197
|
" _ _ ", |
|
198
|
"| | | ", |
|
199
|
"|_ _|", |
|
200
|
" |_| ", |
|
201
|
|
|
202
|
/* 5 */ |
|
203
|
" ___ ", |
|
204
|
"| __|", |
|
205
|
"|__ \\", |
|
206
|
"|___/", |
|
207
|
|
|
208
|
/* 6 */ |
|
209
|
" __ ", |
|
210
|
" / / ", |
|
211
|
"/ _ \\", |
|
212
|
"\\___/", |
|
213
|
|
|
214
|
/* 7 */ |
|
215
|
" ____ ", |
|
216
|
"|__ |", |
|
217
|
" / / ", |
|
218
|
" /_/ ", |
|
219
|
|
|
220
|
/* 8 */ |
|
221
|
" ___ ", |
|
222
|
"( _ )", |
|
223
|
"/ _ \\", |
|
224
|
"\\___/", |
|
225
|
|
|
226
|
/* 9 */ |
|
227
|
" ___ ", |
|
228
|
"/ _ \\", |
|
229
|
"\\_, /", |
|
230
|
" /_/ ", |
|
231
|
|
|
232
|
/* A */ |
|
233
|
" ", |
|
234
|
" /\\ ", |
|
235
|
" / \\ ", |
|
236
|
"/_/\\_\\", |
|
237
|
|
|
238
|
/* B */ |
|
239
|
" ___ ", |
|
240
|
"| _ )", |
|
241
|
"| _ \\", |
|
242
|
"|___/", |
|
243
|
|
|
244
|
/* C */ |
|
245
|
" ___ ", |
|
246
|
" / __|", |
|
247
|
"| (__ ", |
|
248
|
" \\___|", |
|
249
|
|
|
250
|
/* D */ |
|
251
|
" ___ ", |
|
252
|
"| \\ ", |
|
253
|
"| |) |", |
|
254
|
"|___/ ", |
|
255
|
|
|
256
|
/* E */ |
|
257
|
" ___ ", |
|
258
|
"| __|", |
|
259
|
"| _| ", |
|
260
|
"|___|", |
|
261
|
|
|
262
|
/* F */ |
|
263
|
" ___ ", |
|
264
|
"| __|", |
|
265
|
"| _| ", |
|
266
|
"|_| ", |
|
267
|
}; |
|
268
|
|
|
269
|
/* |
|
270
|
** Render an 8-digit hexadecimal string as ascii arg. |
|
271
|
** Space to hold the result is obtained from malloc() and should be freed |
|
272
|
** by the caller. |
|
273
|
*/ |
|
274
|
char *captcha_render(const char *zPw){ |
|
275
|
char *z = fossil_malloc( 7*4*strlen(zPw) + 5 ); |
|
276
|
int i, j, k, m; |
|
277
|
const char *zChar; |
|
278
|
|
|
279
|
k = 0; |
|
280
|
for(i=0; i<4; i++){ |
|
281
|
for(j=0; zPw[j]; j++){ |
|
282
|
unsigned char v = hex_digit_value(zPw[j]); |
|
283
|
zChar = azFont3[4*v + i]; |
|
284
|
for(m=0; zChar[m]; m++){ |
|
285
|
z[k++] = zChar[m]; |
|
286
|
} |
|
287
|
} |
|
288
|
z[k++] = '\n'; |
|
289
|
} |
|
290
|
z[k] = 0; |
|
291
|
return z; |
|
292
|
} |
|
293
|
#endif /* CAPTCHA==3 */ |
|
294
|
|
|
295
|
#if CAPTCHA==4 |
|
296
|
static const char *const azFont4[] = { |
|
297
|
/* 0 */ |
|
298
|
" ___ ", |
|
299
|
" / _ \\ ", |
|
300
|
"| | | |", |
|
301
|
"| | | |", |
|
302
|
"| |_| |", |
|
303
|
" \\___/ ", |
|
304
|
|
|
305
|
/* 1 */ |
|
306
|
" __ ", |
|
307
|
"/_ |", |
|
308
|
" | |", |
|
309
|
" | |", |
|
310
|
" | |", |
|
311
|
" |_|", |
|
312
|
|
|
313
|
/* 2 */ |
|
314
|
" ___ ", |
|
315
|
"|__ \\ ", |
|
316
|
" ) |", |
|
317
|
" / / ", |
|
318
|
" / /_ ", |
|
319
|
"|____|", |
|
320
|
|
|
321
|
/* 3 */ |
|
322
|
" ____ ", |
|
323
|
"|___ \\ ", |
|
324
|
" __) |", |
|
325
|
" |__ < ", |
|
326
|
" ___) |", |
|
327
|
"|____/ ", |
|
328
|
|
|
329
|
/* 4 */ |
|
330
|
" _ _ ", |
|
331
|
"| || | ", |
|
332
|
"| || |_ ", |
|
333
|
"|__ _|", |
|
334
|
" | | ", |
|
335
|
" |_| ", |
|
336
|
|
|
337
|
/* 5 */ |
|
338
|
" _____ ", |
|
339
|
"| ____|", |
|
340
|
"| |__ ", |
|
341
|
"|___ \\ ", |
|
342
|
" ___) |", |
|
343
|
"|____/ ", |
|
344
|
|
|
345
|
/* 6 */ |
|
346
|
" __ ", |
|
347
|
" / / ", |
|
348
|
" / /_ ", |
|
349
|
"| '_ \\ ", |
|
350
|
"| (_) |", |
|
351
|
" \\___/ ", |
|
352
|
|
|
353
|
/* 7 */ |
|
354
|
" ______ ", |
|
355
|
"|____ |", |
|
356
|
" / / ", |
|
357
|
" / / ", |
|
358
|
" / / ", |
|
359
|
" /_/ ", |
|
360
|
|
|
361
|
/* 8 */ |
|
362
|
" ___ ", |
|
363
|
" / _ \\ ", |
|
364
|
"| (_) |", |
|
365
|
" > _ < ", |
|
366
|
"| (_) |", |
|
367
|
" \\___/ ", |
|
368
|
|
|
369
|
/* 9 */ |
|
370
|
" ___ ", |
|
371
|
" / _ \\ ", |
|
372
|
"| (_) |", |
|
373
|
" \\__, |", |
|
374
|
" / / ", |
|
375
|
" /_/ ", |
|
376
|
|
|
377
|
/* A */ |
|
378
|
" ", |
|
379
|
" /\\ ", |
|
380
|
" / \\ ", |
|
381
|
" / /\\ \\ ", |
|
382
|
" / ____ \\ ", |
|
383
|
"/_/ \\_\\", |
|
384
|
|
|
385
|
/* B */ |
|
386
|
" ____ ", |
|
387
|
"| _ \\ ", |
|
388
|
"| |_) |", |
|
389
|
"| _ < ", |
|
390
|
"| |_) |", |
|
391
|
"|____/ ", |
|
392
|
|
|
393
|
/* C */ |
|
394
|
" _____ ", |
|
395
|
" / ____|", |
|
396
|
"| | ", |
|
397
|
"| | ", |
|
398
|
"| |____ ", |
|
399
|
" \\_____|", |
|
400
|
|
|
401
|
/* D */ |
|
402
|
" _____ ", |
|
403
|
"| __ \\ ", |
|
404
|
"| | | |", |
|
405
|
"| | | |", |
|
406
|
"| |__| |", |
|
407
|
"|_____/ ", |
|
408
|
|
|
409
|
/* E */ |
|
410
|
" ______ ", |
|
411
|
"| ____|", |
|
412
|
"| |__ ", |
|
413
|
"| __| ", |
|
414
|
"| |____ ", |
|
415
|
"|______|", |
|
416
|
|
|
417
|
/* F */ |
|
418
|
" ______ ", |
|
419
|
"| ____|", |
|
420
|
"| |__ ", |
|
421
|
"| __| ", |
|
422
|
"| | ", |
|
423
|
"|_| ", |
|
424
|
}; |
|
425
|
|
|
426
|
/* |
|
427
|
** Render an 8-digit hexadecimal string as ascii arg. |
|
428
|
** Space to hold the result is obtained from malloc() and should be freed |
|
429
|
** by the caller. |
|
430
|
*/ |
|
431
|
char *captcha_render(const char *zPw){ |
|
432
|
char *z = fossil_malloc( 10*6*strlen(zPw) + 7 ); |
|
433
|
int i, j, k, m; |
|
434
|
const char *zChar; |
|
435
|
unsigned char x; |
|
436
|
int y; |
|
437
|
|
|
438
|
k = 0; |
|
439
|
for(i=0; i<6; i++){ |
|
440
|
x = 0; |
|
441
|
for(j=0; zPw[j]; j++){ |
|
442
|
unsigned char v = hex_digit_value(zPw[j]); |
|
443
|
x = (x<<4) + v; |
|
444
|
switch( x ){ |
|
445
|
case 0x7a: |
|
446
|
case 0xfa: |
|
447
|
y = 3; |
|
448
|
break; |
|
449
|
case 0x47: |
|
450
|
y = 2; |
|
451
|
break; |
|
452
|
case 0xf6: |
|
453
|
case 0xa9: |
|
454
|
case 0xa4: |
|
455
|
case 0xa1: |
|
456
|
case 0x9a: |
|
457
|
case 0x76: |
|
458
|
case 0x61: |
|
459
|
case 0x67: |
|
460
|
case 0x69: |
|
461
|
case 0x41: |
|
462
|
case 0x42: |
|
463
|
case 0x43: |
|
464
|
case 0x4a: |
|
465
|
y = 1; |
|
466
|
break; |
|
467
|
default: |
|
468
|
y = 0; |
|
469
|
break; |
|
470
|
} |
|
471
|
zChar = azFont4[6*v + i]; |
|
472
|
while( y && zChar[0]==' ' ){ y--; zChar++; } |
|
473
|
while( y && z[k-1]==' ' ){ y--; k--; } |
|
474
|
for(m=0; zChar[m]; m++){ |
|
475
|
z[k++] = zChar[m]; |
|
476
|
} |
|
477
|
} |
|
478
|
z[k++] = '\n'; |
|
479
|
} |
|
480
|
z[k] = 0; |
|
481
|
return z; |
|
482
|
} |
|
483
|
#endif /* CAPTCHA==4 */ |
|
484
|
|
|
485
|
/* |
|
486
|
** COMMAND: test-captcha |
|
487
|
** |
|
488
|
** Render an ASCII-art captcha for numbers given on the command line. |
|
489
|
*/ |
|
490
|
void test_captcha(void){ |
|
491
|
int i; |
|
492
|
sqlite3_uint64 v; |
|
493
|
char *z; |
|
494
|
|
|
495
|
for(i=2; i<g.argc; i++){ |
|
496
|
char zHex[30]; |
|
497
|
v = (sqlite3_uint64)strtoll(g.argv[i],0,0); |
|
498
|
sqlite3_snprintf(sizeof(zHex), zHex, "%llx", v); |
|
499
|
z = captcha_render(zHex); |
|
500
|
fossil_print("%s:\n%s", zHex, z); |
|
501
|
free(z); |
|
502
|
} |
|
503
|
} |
|
504
|
|
|
505
|
/* |
|
506
|
** Compute a seed value for a captcha. The seed is public and is sent |
|
507
|
** as a hidden parameter with the page that contains the captcha. Knowledge |
|
508
|
** of the seed is insufficient for determining the captcha without additional |
|
509
|
** information held only on the server and never revealed. |
|
510
|
*/ |
|
511
|
unsigned int captcha_seed(void){ |
|
512
|
unsigned int x; |
|
513
|
sqlite3_randomness(sizeof(x), &x); |
|
514
|
x &= 0x7fffffff; |
|
515
|
return x; |
|
516
|
} |
|
517
|
|
|
518
|
/* The SQL that will rotate the captcha-secret. */ |
|
519
|
static const char captchaSecretRotationSql[] = |
|
520
|
@ SAVEPOINT rotate; |
|
521
|
@ DELETE FROM config |
|
522
|
@ WHERE name GLOB 'captcha-secret-*' |
|
523
|
@ AND mtime<unixepoch('now','-6 hours'); |
|
524
|
@ UPDATE config |
|
525
|
@ SET name=format('captcha-secret-%%d',substr(name,16)+1) |
|
526
|
@ WHERE name GLOB 'captcha-secret-*'; |
|
527
|
@ UPDATE config |
|
528
|
@ SET name='captcha-secret-1', mtime=unixepoch() |
|
529
|
@ WHERE name='captcha-secret'; |
|
530
|
@ REPLACE INTO config(name,value,mtime) |
|
531
|
@ VALUES('captcha-secret',%Q,unixepoch()); |
|
532
|
@ RELEASE rotate; |
|
533
|
; |
|
534
|
|
|
535
|
|
|
536
|
/* |
|
537
|
** Create a new random captcha-secret. Rotate the old one into |
|
538
|
** the captcha-secret-N backups. Purge captcha-secret-N backups |
|
539
|
** older than 6 hours. |
|
540
|
** |
|
541
|
** Do this on the current database and in all other databases of |
|
542
|
** the same login group. |
|
543
|
*/ |
|
544
|
void captcha_secret_rotate(void){ |
|
545
|
char *zNew = db_text(0, "SELECT lower(hex(randomblob(20)))"); |
|
546
|
char *zSql = mprintf(captchaSecretRotationSql/*works-like:"%Q"*/, zNew); |
|
547
|
char *zErrs = 0; |
|
548
|
fossil_free(zNew); |
|
549
|
db_unprotect(PROTECT_CONFIG); |
|
550
|
db_begin_transaction(); |
|
551
|
sqlite3_exec(g.db, zSql, 0, 0, &zErrs); |
|
552
|
db_protect_pop(); |
|
553
|
if( zErrs && zErrs[0] ){ |
|
554
|
db_rollback_transaction(); |
|
555
|
fossil_fatal("Unable to rotate captcha-secret\n%s\nERROR: %s\n", |
|
556
|
zSql, zErrs); |
|
557
|
} |
|
558
|
db_end_transaction(0); |
|
559
|
login_group_sql(zSql, "", "", &zErrs); |
|
560
|
if( zErrs ){ |
|
561
|
sqlite3_free(zErrs); /* Silently ignore errors on other repos */ |
|
562
|
} |
|
563
|
fossil_free(zSql); |
|
564
|
} |
|
565
|
|
|
566
|
/* |
|
567
|
** Return the value of the N-th more recent captcha-secret. The |
|
568
|
** most recent captcha-secret is 0. Others are prior captcha-secrets |
|
569
|
** that have expired, but are retained for a limited period of time |
|
570
|
** so that pending anonymous login cookies and/or captcha dialogs |
|
571
|
** don't malfunction when the captcha-secret changes. |
|
572
|
** |
|
573
|
** Clients should start by using the 0-th captcha-secret. Only if |
|
574
|
** that one does not work should they advance to 1 and 2 and so forth, |
|
575
|
** until this routine returns a NULL pointer. |
|
576
|
** |
|
577
|
** The value returned is a string obtained from fossil_malloc() and |
|
578
|
** should be freed by the caller. |
|
579
|
** |
|
580
|
** The 0-th captcha secret is the value of Config.Name='captcha-secret'. |
|
581
|
** For N>0, the value is in Config.Name='captcha-secret-$N'. |
|
582
|
*/ |
|
583
|
char *captcha_secret(int N){ |
|
584
|
if( N==0 ){ |
|
585
|
return db_text(0, "SELECT value FROM config WHERE name='captcha-secret'"); |
|
586
|
}else{ |
|
587
|
return db_text(0, |
|
588
|
"SELECT value FROM config" |
|
589
|
" WHERE name='captcha-secret-%d'" |
|
590
|
" AND mtime>unixepoch('now','-6 hours')", N); |
|
591
|
} |
|
592
|
} |
|
593
|
|
|
594
|
/* |
|
595
|
** Translate a captcha seed value into the captcha password string. |
|
596
|
** The returned string is static and overwritten on each call to |
|
597
|
** this function. |
|
598
|
** |
|
599
|
** Use the N-th captcha secret to compute the password. When N==0, |
|
600
|
** a valid password is always returned. A new captcha-secret will |
|
601
|
** be created if necessary. But for N>0, the return value might |
|
602
|
** be NULL to indicate that there is no N-th captcha-secret. |
|
603
|
*/ |
|
604
|
const char *captcha_decode(unsigned int seed, int N){ |
|
605
|
char *zSecret; |
|
606
|
const char *z; |
|
607
|
Blob b; |
|
608
|
static char zRes[20]; |
|
609
|
|
|
610
|
zSecret = captcha_secret(N); |
|
611
|
if( zSecret==0 ){ |
|
612
|
if( N>0 ) return 0; |
|
613
|
db_unprotect(PROTECT_CONFIG); |
|
614
|
db_multi_exec( |
|
615
|
"REPLACE INTO config(name,value)" |
|
616
|
" VALUES('captcha-secret', lower(hex(randomblob(20))));" |
|
617
|
); |
|
618
|
db_protect_pop(); |
|
619
|
zSecret = captcha_secret(0); |
|
620
|
assert( zSecret!=0 ); |
|
621
|
} |
|
622
|
blob_init(&b, 0, 0); |
|
623
|
blob_appendf(&b, "%s-%x", zSecret, seed); |
|
624
|
sha1sum_blob(&b, &b); |
|
625
|
z = blob_buffer(&b); |
|
626
|
memcpy(zRes, z, 8); |
|
627
|
zRes[8] = 0; |
|
628
|
fossil_free(zSecret); |
|
629
|
return zRes; |
|
630
|
} |
|
631
|
|
|
632
|
/* |
|
633
|
** Return true if a CAPTCHA is required for editing wiki or tickets or for |
|
634
|
** adding attachments. |
|
635
|
** |
|
636
|
** A CAPTCHA is required in those cases if the user is not logged in (if they |
|
637
|
** are user "nobody") and if the "require-captcha" setting is true. The |
|
638
|
** "require-captcha" setting is controlled on the Admin/Access page. It |
|
639
|
** defaults to true. |
|
640
|
*/ |
|
641
|
int captcha_needed(void){ |
|
642
|
return login_is_nobody() && db_get_boolean("require-captcha", 1); |
|
643
|
} |
|
644
|
|
|
645
|
/* |
|
646
|
** If a captcha is required but the correct captcha code is not supplied |
|
647
|
** in the query parameters, then return false (0). |
|
648
|
** |
|
649
|
** If no captcha is required or if the correct captcha is supplied, return |
|
650
|
** true (non-zero). |
|
651
|
** |
|
652
|
** The query parameters examined are "captchaseed" for the seed value and |
|
653
|
** "captcha" for text that the user types in response to the captcha prompt. |
|
654
|
*/ |
|
655
|
int captcha_is_correct(int bAlwaysNeeded){ |
|
656
|
const char *zSeed; |
|
657
|
const char *zEntered; |
|
658
|
const char *zDecode; |
|
659
|
char z[30]; |
|
660
|
int i; |
|
661
|
int n = 0; |
|
662
|
if( !bAlwaysNeeded && !captcha_needed() ){ |
|
663
|
return 1; /* No captcha needed */ |
|
664
|
} |
|
665
|
zSeed = P("captchaseed"); |
|
666
|
if( zSeed==0 ) return 0; |
|
667
|
zEntered = P("captcha"); |
|
668
|
if( zEntered==0 || strlen(zEntered)!=8 ) return 0; |
|
669
|
do{ |
|
670
|
zDecode = captcha_decode((unsigned int)atoi(zSeed), n++); |
|
671
|
if( zDecode==0 ) return 0; |
|
672
|
assert( strlen(zDecode)==8 ); |
|
673
|
for(i=0; i<8; i++){ |
|
674
|
char c = zEntered[i]; |
|
675
|
if( c>='A' && c<='F' ) c += 'a' - 'A'; |
|
676
|
if( c=='O' ) c = '0'; |
|
677
|
z[i] = c; |
|
678
|
} |
|
679
|
}while( strncmp(zDecode,z,8)!=0 ); |
|
680
|
return 1; |
|
681
|
} |
|
682
|
|
|
683
|
/* |
|
684
|
** Generate a captcha display together with the necessary hidden parameter |
|
685
|
** for the seed and the entry box into which the user will type the text of |
|
686
|
** the captcha. This is typically done at the very bottom of a form. |
|
687
|
** |
|
688
|
** This routine is a no-op if no captcha is required. |
|
689
|
** |
|
690
|
** Flag values: |
|
691
|
** |
|
692
|
** 0x01 Show the "Submit" button in the form. |
|
693
|
** 0x02 Always generate the captcha, even if not required |
|
694
|
*/ |
|
695
|
void captcha_generate(int mFlags){ |
|
696
|
unsigned int uSeed; |
|
697
|
const char *zDecoded; |
|
698
|
char *zCaptcha; |
|
699
|
|
|
700
|
if( !captcha_needed() && (mFlags & 0x02)==0 ) return; |
|
701
|
uSeed = captcha_seed(); |
|
702
|
zDecoded = captcha_decode(uSeed, 0); |
|
703
|
zCaptcha = captcha_render(zDecoded); |
|
704
|
@ <div class="captcha"><table class="captcha"><tr><td><pre class="captcha"> |
|
705
|
@ %h(zCaptcha) |
|
706
|
@ </pre> |
|
707
|
@ Enter security code shown above: |
|
708
|
@ <input type="hidden" name="captchaseed" value="%u(uSeed)"> |
|
709
|
@ <input type="text" name="captcha" size="8" autofocus> |
|
710
|
if( mFlags & 0x01 ){ |
|
711
|
@ <input type="submit" value="Submit"> |
|
712
|
} |
|
713
|
@ <br/>\ |
|
714
|
captcha_speakit_button(uSeed, 0); |
|
715
|
@ </td></tr></table></div> |
|
716
|
} |
|
717
|
|
|
718
|
/* |
|
719
|
** Add a "Speak the captcha" button. |
|
720
|
*/ |
|
721
|
void captcha_speakit_button(unsigned int uSeed, const char *zMsg){ |
|
722
|
if( zMsg==0 ) zMsg = "Speak the text"; |
|
723
|
@ <input aria-label="%h(zMsg)" type="button" value="%h(zMsg)" \ |
|
724
|
@ id="speakthetext"> |
|
725
|
@ <script nonce="%h(style_nonce())">/* captcha_speakit_button() */ |
|
726
|
@ document.getElementById("speakthetext").onclick = function(){ |
|
727
|
@ var audio = window.fossilAudioCaptcha \ |
|
728
|
@ || new Audio("%R/captcha-audio/%u(uSeed)"); |
|
729
|
@ window.fossilAudioCaptcha = audio; |
|
730
|
@ audio.currentTime = 0; |
|
731
|
@ audio.play(); |
|
732
|
@ } |
|
733
|
@ </script> |
|
734
|
} |
|
735
|
|
|
736
|
/* |
|
737
|
** WEBPAGE: test-captcha |
|
738
|
** |
|
739
|
** If the name query parameter is provided, then render the hex value of |
|
740
|
** the name using the captcha font. |
|
741
|
** |
|
742
|
** Otherwise render the captcha screen. The "show-button" parameter causes |
|
743
|
** the submit button to be rendered. |
|
744
|
*/ |
|
745
|
void captcha_test(void){ |
|
746
|
const char *zPw = P("name"); |
|
747
|
if( zPw==0 || zPw[0]==0 ){ |
|
748
|
(void)exclude_spiders(1); |
|
749
|
@ <hr><p>The captcha is shown above. Add a name=HEX query parameter |
|
750
|
@ to see how HEX would be rendered in the current captcha font. |
|
751
|
@ <h2>Debug/Testing Values:</h2> |
|
752
|
@ <ul> |
|
753
|
@ <li> g.isRobot = %d(g.isRobot) |
|
754
|
@ <li> g.zLogin = %h(g.zLogin) |
|
755
|
@ <li> login_cookie_welformed() = %d(login_cookie_wellformed()) |
|
756
|
@ <li> captcha_is_correct(1) = %d(captcha_is_correct(1)). |
|
757
|
@ </ul> |
|
758
|
style_finish_page(); |
|
759
|
}else{ |
|
760
|
style_set_current_feature("test"); |
|
761
|
style_header("Captcha Test"); |
|
762
|
@ <pre class="captcha"> |
|
763
|
@ %s(captcha_render(zPw)) |
|
764
|
@ </pre> |
|
765
|
style_finish_page(); |
|
766
|
} |
|
767
|
} |
|
768
|
|
|
769
|
/* |
|
770
|
** WEBPAGE: honeypot |
|
771
|
** This page is a honeypot for spiders and bots. |
|
772
|
*/ |
|
773
|
void honeypot_page(void){ |
|
774
|
(void)exclude_spiders(0); |
|
775
|
} |
|
776
|
|
|
777
|
/* |
|
778
|
** Check to see if the current request is coming from an agent that |
|
779
|
** self-identifies as a spider. |
|
780
|
** |
|
781
|
** If the agent does not claim to be a spider or if the user has logged |
|
782
|
** in (even as anonymous), then return 0 without doing anything. |
|
783
|
** |
|
784
|
** But if the user agent does self-identify as a spider and there is |
|
785
|
** no login, offer a captcha challenge to allow the user agent to prove |
|
786
|
** that he is human and return non-zero. |
|
787
|
** |
|
788
|
** If the bTest argument is non-zero, then show the captcha regardless of |
|
789
|
** how the agent identifies. This is used for testing only. |
|
790
|
*/ |
|
791
|
int exclude_spiders(int bTest){ |
|
792
|
if( !bTest ){ |
|
793
|
if( g.zLogin!=0 ) return 0; /* Logged in. Consider them human */ |
|
794
|
if( login_cookie_wellformed() ){ |
|
795
|
/* Logged into another member of the login group */ |
|
796
|
return 0; |
|
797
|
} |
|
798
|
} |
|
799
|
|
|
800
|
/* This appears to be a spider. Offer the captcha */ |
|
801
|
style_set_current_feature("captcha"); |
|
802
|
style_header("Captcha"); |
|
803
|
style_submenu_enable(0); |
|
804
|
@ <form method='POST' action='%R/ityaar'> |
|
805
|
@ <h2>Prove that you are human: |
|
806
|
if( bTest ){ |
|
807
|
@ <input type="hidden" name="istest" value="1"> |
|
808
|
} |
|
809
|
captcha_generate(3); |
|
810
|
@ </form> |
|
811
|
if( !bTest ){ |
|
812
|
if( P("fossil-goto")==0 ){ |
|
813
|
cgi_set_cookie("fossil-goto", cgi_reconstruct_original_url(), 0, 600); |
|
814
|
} |
|
815
|
cgi_append_header("X-Robot: 1\r\n"); |
|
816
|
style_finish_page(); |
|
817
|
} |
|
818
|
return 1; |
|
819
|
} |
|
820
|
|
|
821
|
/* |
|
822
|
** WEBPAGE: ityaar |
|
823
|
** |
|
824
|
** This is the action for the form that is the captcha. Not intended |
|
825
|
** for external use. "ityaar" is an acronym "I Think You Are A Robot". |
|
826
|
** |
|
827
|
** If the captcha is correctly solved, then an anonymous login cookie |
|
828
|
** is set. Regardless of whether or not the captcha was solved, this |
|
829
|
** page always redirects to the fossil-goto cookie. |
|
830
|
*/ |
|
831
|
void captcha_callback(void){ |
|
832
|
int bTest = atoi(PD("istest","0")); |
|
833
|
if( captcha_is_correct(1) ){ |
|
834
|
if( bTest==0 ){ |
|
835
|
if( !login_cookie_wellformed() ){ |
|
836
|
/* ^^^^--- Don't overwrite a valid login on another repo! */ |
|
837
|
login_set_anon_cookie(0, 0); |
|
838
|
} |
|
839
|
cgi_append_header("X-Robot: 0\r\n"); |
|
840
|
} |
|
841
|
login_redirect_to_g(); |
|
842
|
}else{ |
|
843
|
g.isRobot = 1; |
|
844
|
(void)exclude_spiders(bTest); |
|
845
|
if( bTest ){ |
|
846
|
@ <hr><p>Wrong code. Try again |
|
847
|
style_finish_page(); |
|
848
|
} |
|
849
|
} |
|
850
|
} |
|
851
|
|
|
852
|
|
|
853
|
/* |
|
854
|
** Generate a WAV file that reads aloud the hex digits given by |
|
855
|
** zHex. |
|
856
|
*/ |
|
857
|
static void captcha_wav(const char *zHex, Blob *pOut){ |
|
858
|
int i; |
|
859
|
const int szWavHdr = 44; |
|
860
|
blob_init(pOut, 0, 0); |
|
861
|
blob_resize(pOut, szWavHdr); /* Space for the WAV header */ |
|
862
|
pOut->nUsed = szWavHdr; |
|
863
|
memset(pOut->aData, 0, szWavHdr); |
|
864
|
if( zHex==0 || zHex[0]==0 ) zHex = "0"; |
|
865
|
for(i=0; zHex[i]; i++){ |
|
866
|
int v = hex_digit_value(zHex[i]); |
|
867
|
int sz; |
|
868
|
int nData; |
|
869
|
const unsigned char *pData; |
|
870
|
char zSoundName[50]; |
|
871
|
sqlite3_snprintf(sizeof(zSoundName),zSoundName,"sounds/%c.wav", |
|
872
|
"0123456789abcdef"[v]); |
|
873
|
/* Extra silence in between letters */ |
|
874
|
if( i>0 ){ |
|
875
|
int nQuiet = 3000; |
|
876
|
blob_resize(pOut, pOut->nUsed+nQuiet); |
|
877
|
memset(pOut->aData+pOut->nUsed-nQuiet, 0x80, nQuiet); |
|
878
|
} |
|
879
|
pData = builtin_file(zSoundName, &sz); |
|
880
|
nData = sz - szWavHdr; |
|
881
|
blob_resize(pOut, pOut->nUsed+nData); |
|
882
|
memcpy(pOut->aData+pOut->nUsed-nData, pData+szWavHdr, nData); |
|
883
|
if( zHex[i+1]==0 ){ |
|
884
|
int len = pOut->nUsed + 36; |
|
885
|
memcpy(pOut->aData, pData, szWavHdr); |
|
886
|
pOut->aData[4] = (char)(len&0xff); |
|
887
|
pOut->aData[5] = (char)((len>>8)&0xff); |
|
888
|
pOut->aData[6] = (char)((len>>16)&0xff); |
|
889
|
pOut->aData[7] = (char)((len>>24)&0xff); |
|
890
|
len = pOut->nUsed; |
|
891
|
pOut->aData[40] = (char)(len&0xff); |
|
892
|
pOut->aData[41] = (char)((len>>8)&0xff); |
|
893
|
pOut->aData[42] = (char)((len>>16)&0xff); |
|
894
|
pOut->aData[43] = (char)((len>>24)&0xff); |
|
895
|
} |
|
896
|
} |
|
897
|
} |
|
898
|
|
|
899
|
/* |
|
900
|
** WEBPAGE: /captcha-audio |
|
901
|
** |
|
902
|
** Return a WAV file that pronounces the digits of the captcha that |
|
903
|
** is determined by the seed given in the name= query parameter. |
|
904
|
*/ |
|
905
|
void captcha_wav_page(void){ |
|
906
|
const char *zSeed = PD("name","0"); |
|
907
|
const char *zDecode = captcha_decode((unsigned int)atoi(zSeed), 0); |
|
908
|
Blob audio; |
|
909
|
captcha_wav(zDecode, &audio); |
|
910
|
cgi_set_content_type("audio/wav"); |
|
911
|
cgi_set_content(&audio); |
|
912
|
} |
|
913
|
|
|
914
|
/* |
|
915
|
** WEBPAGE: /test-captcha-audio |
|
916
|
** |
|
917
|
** Return a WAV file that pronounces the hex digits of the name= |
|
918
|
** query parameter. |
|
919
|
*/ |
|
920
|
void captcha_test_wav_page(void){ |
|
921
|
const char *zSeed = P("name"); |
|
922
|
Blob audio; |
|
923
|
captcha_wav(zSeed, &audio); |
|
924
|
cgi_set_content_type("audio/wav"); |
|
925
|
cgi_set_content(&audio); |
|
926
|
} |
|
927
|
|