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
525
526
|
/* Copyright (c) 2007-2008, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/* $Id: /tor/trunk/src/or/networkstatus.c 15493 2007-12-16T18:33:25.055570Z nickm $ */
const char geoip_c_id[] =
"$Id: /tor/trunk/src/or/networkstatus.c 15493 2007-12-16T18:33:25.055570Z nickm $";
/**
* \file geoip.c
* \brief Functions related to maintaining an IP-to-country database and to
* summarizing client connections by country.
*/
#define GEOIP_PRIVATE
#include "or.h"
#include "ht.h"
static void clear_geoip_db(void);
/** An entry from the GeoIP file: maps an IP range to a country. */
typedef struct geoip_entry_t {
uint32_t ip_low; /**< The lowest IP in the range, in host order */
uint32_t ip_high; /**< The highest IP in the range, in host order */
intptr_t country; /**< An index into geoip_countries */
} geoip_entry_t;
/** A list of lowercased two-letter country codes. */
static smartlist_t *geoip_countries = NULL;
/** A map from lowercased country codes to their position in geoip_countries.
* The index is encoded in the pointer, and 1 is added so that NULL can mean
* not found. */
static strmap_t *country_idxplus1_by_lc_code = NULL;
/** A list of all known geoip_entry_t, sorted by ip_low. */
static smartlist_t *geoip_entries = NULL;
/** Add an entry to the GeoIP table, mapping all IPs between <b>low</b> and
* <b>high</b>, inclusive, to the 2-letter country code <b>country</b>.
*/
static void
geoip_add_entry(uint32_t low, uint32_t high, const char *country)
{
intptr_t idx;
geoip_entry_t *ent;
void *_idxplus1;
if (high < low)
return;
_idxplus1 = strmap_get_lc(country_idxplus1_by_lc_code, country);
if (!_idxplus1) {
char *c = tor_strdup(country);
tor_strlower(c);
smartlist_add(geoip_countries, c);
idx = smartlist_len(geoip_countries) - 1;
strmap_set_lc(country_idxplus1_by_lc_code, country, (void*)(idx+1));
} else {
idx = ((uintptr_t)_idxplus1)-1;
}
tor_assert(!strcasecmp(smartlist_get(geoip_countries, idx), country));
ent = tor_malloc_zero(sizeof(geoip_entry_t));
ent->ip_low = low;
ent->ip_high = high;
ent->country = idx;
smartlist_add(geoip_entries, ent);
}
/** Add an entry to the GeoIP table, parsing it from <b>line</b>. The
* format is as for geoip_load_file(). */
/*private*/ int
geoip_parse_entry(const char *line)
{
unsigned int low, high;
char b[3];
if (!geoip_countries) {
geoip_countries = smartlist_create();
geoip_entries = smartlist_create();
country_idxplus1_by_lc_code = strmap_new();
}
while (TOR_ISSPACE(*line))
++line;
if (*line == '#')
return 0;
if (sscanf(line,"%u,%u,%2s", &low, &high, b) == 3) {
geoip_add_entry(low, high, b);
return 0;
} else if (sscanf(line,"\"%u\",\"%u\",\"%2s\",", &low, &high, b) == 3) {
geoip_add_entry(low, high, b);
return 0;
} else {
log_warn(LD_GENERAL, "Unable to parse line from GEOIP file: %s",
escaped(line));
return -1;
}
}
/** Sorting helper: return -1, 1, or 0 based on comparison of two
* geoip_entry_t */
static int
_geoip_compare_entries(const void **_a, const void **_b)
{
const geoip_entry_t *a = *_a, *b = *_b;
if (a->ip_low < b->ip_low)
return -1;
else if (a->ip_low > b->ip_low)
return 1;
else
return 0;
}
/** bsearch helper: return -1, 1, or 0 based on comparison of an IP (a pointer
* to a uint32_t in host order) to a geoip_entry_t */
static int
_geoip_compare_key_to_entry(const void *_key, const void **_member)
{
const uint32_t addr = *(uint32_t *)_key;
const geoip_entry_t *entry = *_member;
if (addr < entry->ip_low)
return -1;
else if (addr > entry->ip_high)
return 1;
else
return 0;
}
/** Return 1 if we should collect geoip stats on bridge users, and
* include them in our extrainfo descriptor. Else return 0. */
int
should_record_bridge_info(or_options_t *options)
{
return options->BridgeRelay && options->BridgeRecordUsageByCountry;
}
/** Clear the GeoIP database and reload it from the file
* <b>filename</b>. Return 0 on success, -1 on failure.
*
* Recognized line formats are:
* INTIPLOW,INTIPHIGH,CC
* and
* "INTIPLOW","INTIPHIGH","CC","CC3","COUNTRY NAME"
* where INTIPLOW and INTIPHIGH are IPv4 addresses encoded as 4-byte unsigned
* integers, and CC is a country code.
*
* It also recognizes, and skips over, blank lines and lines that start
* with '#' (comments).
*/
int
geoip_load_file(const char *filename, or_options_t *options)
{
FILE *f;
int severity = should_record_bridge_info(options) ? LOG_WARN : LOG_INFO;
clear_geoip_db();
if (!(f = fopen(filename, "r"))) {
log_fn(severity, LD_GENERAL, "Failed to open GEOIP file %s.", filename);
return -1;
}
geoip_countries = smartlist_create();
geoip_entries = smartlist_create();
country_idxplus1_by_lc_code = strmap_new();
log_info(LD_GENERAL, "Parsing GEOIP file.");
while (!feof(f)) {
char buf[512];
if (fgets(buf, (int)sizeof(buf), f) == NULL)
break;
/* FFFF track full country name. */
geoip_parse_entry(buf);
}
/*XXXX020 abort and return -1 if no entries/illformed?*/
fclose(f);
smartlist_sort(geoip_entries, _geoip_compare_entries);
return 0;
}
/** Given an IP address in host order, return a number representing the
* country to which that address belongs, or -1 for unknown. The return value
* will always be less than geoip_get_n_countries(). To decode it,
* call geoip_get_country_name().
*/
int
geoip_get_country_by_ip(uint32_t ipaddr)
{
geoip_entry_t *ent;
if (!geoip_entries)
return -1;
ent = smartlist_bsearch(geoip_entries, &ipaddr, _geoip_compare_key_to_entry);
return ent ? (int)ent->country : -1;
}
/** Return the number of countries recognized by the GeoIP database. */
int
geoip_get_n_countries(void)
{
return (int) smartlist_len(geoip_countries);
}
/** Return the two-letter country code associated with the number <b>num</b>,
* or "??" for an unknown value. */
const char *
geoip_get_country_name(int num)
{
if (geoip_countries && num >= 0 && num < smartlist_len(geoip_countries))
return smartlist_get(geoip_countries, num);
else
return "??";
}
/** Return true iff we have loaded a GeoIP database.*/
int
geoip_is_loaded(void)
{
return geoip_countries != NULL && geoip_entries != NULL;
}
/** Entry in a map from IP address to the last time we've seen an incoming
* connection from that IP address. Used by bridges only, to track which
* countries have them blocked. */
typedef struct clientmap_entry_t {
HT_ENTRY(clientmap_entry_t) node;
uint32_t ipaddr;
time_t last_seen; /* The last 2 bits of this value hold the client
* operation. */
} clientmap_entry_t;
#define ACTION_MASK 3
/** Map from client IP address to last time seen. */
static HT_HEAD(clientmap, clientmap_entry_t) client_history =
HT_INITIALIZER();
/** Time at which we started tracking client history. */
static time_t client_history_starts = 0;
/** Hashtable helper: compute a hash of a clientmap_entry_t. */
static INLINE unsigned
clientmap_entry_hash(const clientmap_entry_t *a)
{
return ht_improve_hash((unsigned) a->ipaddr);
}
/** Hashtable helper: compare two clientmap_entry_t values for equality. */
static INLINE int
clientmap_entries_eq(const clientmap_entry_t *a, const clientmap_entry_t *b)
{
return a->ipaddr == b->ipaddr;
}
HT_PROTOTYPE(clientmap, clientmap_entry_t, node, clientmap_entry_hash,
clientmap_entries_eq);
HT_GENERATE(clientmap, clientmap_entry_t, node, clientmap_entry_hash,
clientmap_entries_eq, 0.6, malloc, realloc, free);
/** Note that we've seen a client connect from the IP <b>addr</b> (host order)
* at time <b>now</b>. Ignored by all but bridges. */
void
geoip_note_client_seen(geoip_client_action_t action,
uint32_t addr, time_t now)
{
or_options_t *options = get_options();
clientmap_entry_t lookup, *ent;
if (action == GEOIP_CLIENT_CONNECT) {
if (!(options->BridgeRelay && options->BridgeRecordUsageByCountry))
return;
} else {
#ifndef ENABLE_GEOIP_STATS
return;
#else
if (options->BridgeRelay || options->BridgeAuthoritativeDir ||
!options->DirRecordUsageByCountry)
return;
#endif
}
/* We use the low 3 bits of the time to encode the action. Since we're
* potentially remembering times of clients, we don't want to make
* clientmap_entry_t larger than it has to be. */
now = (now & ~ACTION_MASK) | (((int)action) & ACTION_MASK);
lookup.ipaddr = addr;
ent = HT_FIND(clientmap, &client_history, &lookup);
if (ent) {
ent->last_seen = now;
} else {
ent = tor_malloc_zero(sizeof(clientmap_entry_t));
ent->ipaddr = addr;
ent->last_seen = now;
HT_INSERT(clientmap, &client_history, ent);
}
if (!client_history_starts)
client_history_starts = now;
}
/** HT_FOREACH helper: remove a clientmap_entry_t from the hashtable if it's
* older than a certain time. */
static int
_remove_old_client_helper(struct clientmap_entry_t *ent, void *_cutoff)
{
time_t cutoff = *(time_t*)_cutoff;
if (ent->last_seen < cutoff) {
tor_free(ent);
return 1;
} else {
return 0;
}
}
/** Forget about all clients that haven't connected since <b>cutoff</b>. */
void
geoip_remove_old_clients(time_t cutoff)
{
clientmap_HT_FOREACH_FN(&client_history,
_remove_old_client_helper,
&cutoff);
if (client_history_starts < cutoff)
client_history_starts = cutoff;
}
/** Do not mention any country from which fewer than this number of IPs have
* connected. This conceivably avoids reporting information that could
* deanonymize users, though analysis is lacking. */
#define MIN_IPS_TO_NOTE_COUNTRY 0
/** Do not report any geoip data at all if we have fewer than this number of
* IPs to report about. */
#define MIN_IPS_TO_NOTE_ANYTHING 0
/** When reporting geoip data about countries, round up to the nearest
* multiple of this value. */
#define IP_GRANULARITY 8
/** Return the time at which we started recording geoip data. */
time_t
geoip_get_history_start(void)
{
return client_history_starts;
}
/** Helper type: used to sort per-country totals by value. */
typedef struct c_hist_t {
char country[3]; /**< Two-letter country code. */
unsigned total; /**< Total IP addresses seen in this country. */
} c_hist_t;
/** Sorting helper: return -1, 1, or 0 based on comparison of two
* geoip_entry_t. Sort in descending order of total, and then by country
* code. */
static int
_c_hist_compare(const void **_a, const void **_b)
{
const c_hist_t *a = *_a, *b = *_b;
if (a->total > b->total)
return -1;
else if (a->total < b->total)
return 1;
else
return strcmp(a->country, b->country);
}
/** Return a newly allocated comma-separated string containing entries for all
* the countries from which we've seen enough clients connect. The entry
* format is cc=num where num is the number of IPs we've seen connecting from
* that country, and cc is a lowercased country code. Returns NULL if we don't
* want to export geoip data yet. */
char *
geoip_get_client_history(time_t now, geoip_client_action_t action)
{
char *result = NULL;
if (!geoip_is_loaded())
return NULL;
if (client_history_starts < (now - 12*60*60)) {
char buf[32];
smartlist_t *chunks = NULL;
smartlist_t *entries = NULL;
int n_countries = geoip_get_n_countries();
int i;
clientmap_entry_t **ent;
unsigned *counts = tor_malloc_zero(sizeof(unsigned)*n_countries);
unsigned total = 0;
HT_FOREACH(ent, clientmap, &client_history) {
int country;
if (((*ent)->last_seen & ACTION_MASK) != action)
continue;
country = geoip_get_country_by_ip((*ent)->ipaddr);
if (country < 0)
continue;
tor_assert(0 <= country && country < n_countries);
++counts[country];
++total;
}
/* Don't record anything if we haven't seen enough IPs. */
#if (MIN_IPS_TO_NOTE_ANYTHING > 0)
if (total < MIN_IPS_TO_NOTE_ANYTHING)
goto done;
#endif
/* Make a list of c_hist_t */
entries = smartlist_create();
for (i = 0; i < n_countries; ++i) {
unsigned c = counts[i];
const char *countrycode;
c_hist_t *ent;
/* Only report a country if it has a minimum number of IPs. */
#if (MIN_IPS_TO_NOTE_COUNTRY > 0)
if (c >= MIN_IPS_TO_NOTE_COUNTRY) {
#else
if (c > 0) {
#endif
/* Round up to the next multiple of IP_GRANULARITY */
c += IP_GRANULARITY-1;
c -= c % IP_GRANULARITY;
countrycode = geoip_get_country_name(i);
ent = tor_malloc(sizeof(c_hist_t));
strlcpy(ent->country, countrycode, sizeof(ent->country));
ent->total = c;
smartlist_add(entries, ent);
}
}
/* Sort entries. Note that we must do this _AFTER_ rounding, or else
* the sort order could leak info. */
smartlist_sort(entries, _c_hist_compare);
/* Build the result. */
chunks = smartlist_create();
SMARTLIST_FOREACH(entries, c_hist_t *, ch, {
tor_snprintf(buf, sizeof(buf), "%s=%u", ch->country, ch->total);
smartlist_add(chunks, tor_strdup(buf));
});
result = smartlist_join_strings(chunks, ",", 0, NULL);
#if (MIN_IPS_TO_NOTE_ANYTHING > 0)
done:
#endif
tor_free(counts);
if (chunks) {
SMARTLIST_FOREACH(chunks, char *, c, tor_free(c));
smartlist_free(chunks);
}
if (entries) {
SMARTLIST_FOREACH(entries, c_hist_t *, c, tor_free(c));
smartlist_free(entries);
}
}
return result;
}
void
dump_geoip_stats(void)
{
#ifdef ENABLE_GEOIP_STATS
time_t now = time(NULL);
char *filename = get_datadir_fname("geoip-stats");
char *data_v2 = NULL, *data_v3 = NULL;
char since[ISO_TIME_LEN+1], written[ISO_TIME_LEN+1];
open_file_t *open_file = NULL;
FILE *out;
data_v2 = geoip_get_client_history(now, GEOIP_CLIENT_NETWORKSTATUS_V2);
data_v3 = geoip_get_client_history(now, GEOIP_CLIENT_NETWORKSTATUS);
format_iso_time(since, geoip_get_history_start());
format_iso_time(written, now);
if (!data_v2 || !data_v3)
goto done;
out = start_writing_to_stdio_file(filename, 0, 0600, &open_file);
if (!out)
goto done;
if (fprintf(out, "written %s\nstarted-at %s\nns %s\nns-v2%s\n",
written, since, data_v3, data_v2) < 0)
goto done;
finish_writing_to_file(open_file);
open_file = NULL;
done:
if (open_file)
abort_writing_to_file(open_file);
tor_free(filename);
tor_free(data_v2);
tor_free(data_v3);
#endif
}
/** Helper used to implement GETINFO ip-to-country/... controller command. */
int
getinfo_helper_geoip(control_connection_t *control_conn,
const char *question, char **answer)
{
(void)control_conn;
if (geoip_is_loaded() && !strcmpstart(question, "ip-to-country/")) {
int c;
uint32_t ip;
struct in_addr in;
question += strlen("ip-to-country/");
if (tor_inet_aton(question, &in) != 0) {
ip = ntohl(in.s_addr);
c = geoip_get_country_by_ip(ip);
*answer = tor_strdup(geoip_get_country_name(c));
}
}
return 0;
}
/** Release all storage held by the GeoIP database. */
static void
clear_geoip_db(void)
{
if (geoip_countries) {
SMARTLIST_FOREACH(geoip_countries, char *, cp, tor_free(cp));
smartlist_free(geoip_countries);
}
if (country_idxplus1_by_lc_code)
strmap_free(country_idxplus1_by_lc_code, NULL);
if (geoip_entries) {
SMARTLIST_FOREACH(geoip_entries, geoip_entry_t *, ent, tor_free(ent));
smartlist_free(geoip_entries);
}
geoip_countries = NULL;
country_idxplus1_by_lc_code = NULL;
geoip_entries = NULL;
}
/** Release all storage held in this file. */
void
geoip_free_all(void)
{
clientmap_entry_t **ent, **next, *this;
for (ent = HT_START(clientmap, &client_history); ent != NULL; ent = next) {
this = *ent;
next = HT_NEXT_RMV(clientmap, &client_history, ent);
tor_free(this);
}
HT_CLEAR(clientmap, &client_history);
clear_geoip_db();
}
|