[or-cvs] r12856: Document and clean-up geoip code; give it some unit tests. (in tor/trunk: . src/or)
nickm at seul.org
nickm at seul.org
Tue Dec 18 21:27:08 UTC 2007
Author: nickm
Date: 2007-12-18 16:27:08 -0500 (Tue, 18 Dec 2007)
New Revision: 12856
Modified:
tor/trunk/
tor/trunk/src/or/config.c
tor/trunk/src/or/geoip.c
tor/trunk/src/or/or.h
tor/trunk/src/or/test.c
Log:
r17231 at catbus: nickm | 2007-12-18 16:21:55 -0500
Document and clean-up geoip code; give it some unit tests.
Property changes on: tor/trunk
___________________________________________________________________
svk:merge ticket from /tor/trunk [r17231] on 8246c3cf-6607-4228-993b-4d95d33730f1
Modified: tor/trunk/src/or/config.c
===================================================================
--- tor/trunk/src/or/config.c 2007-12-18 20:41:48 UTC (rev 12855)
+++ tor/trunk/src/or/config.c 2007-12-18 21:27:08 UTC (rev 12856)
@@ -192,7 +192,7 @@
V(FetchServerDescriptors, BOOL, "1"),
V(FetchHidServDescriptors, BOOL, "1"),
V(FetchUselessDescriptors, BOOL, "0"),
- V(GEOIPFile, STRING, NULL),
+ V(GeoIPFile, STRING, NULL),
V(Group, STRING, NULL),
V(HardwareAccel, BOOL, "0"),
V(HashedControlPassword, LINELIST, NULL),
@@ -1217,10 +1217,10 @@
}
/* Maybe load geoip file */
- if (options->GEOIPFile &&
- ((!old_options || !opt_streq(old_options->GEOIPFile, options->GEOIPFile))
+ if (options->GeoIPFile &&
+ ((!old_options || !opt_streq(old_options->GeoIPFile, options->GeoIPFile))
|| !geoip_is_loaded())) {
- geoip_load_file(options->GEOIPFile);
+ geoip_load_file(options->GeoIPFile);
}
/* Check if we need to parse and add the EntryNodes config option. */
if (options->EntryNodes &&
Modified: tor/trunk/src/or/geoip.c
===================================================================
--- tor/trunk/src/or/geoip.c 2007-12-18 20:41:48 UTC (rev 12855)
+++ tor/trunk/src/or/geoip.c 2007-12-18 21:27:08 UTC (rev 12856)
@@ -4,29 +4,49 @@
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"
-/** DOCDOC this whole file */
+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;
- uint32_t ip_high;
- int country;
+ 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 */
+ int 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;
-void
+/** 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)
{
uintptr_t idx;
geoip_entry_t *ent;
- void *_idxplus1 = strmap_get_lc(country_idxplus1_by_lc_code, country);
+ 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);
@@ -44,6 +64,33 @@
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();
+ }
+ 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)
{
@@ -56,6 +103,8 @@
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)
{
@@ -69,11 +118,21 @@
return 0;
}
+/** 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.
+ */
int
geoip_load_file(const char *filename)
{
FILE *f;
- geoip_free_all();
+ clear_geoip_db();
if (!(f = fopen(filename, "r"))) {
log_warn(LD_GENERAL, "Failed to open GEOIP file %s.", filename);
return -1;
@@ -84,19 +143,10 @@
log_info(LD_GENERAL, "Parsing GEOIP file.");
while (!feof(f)) {
char buf[512];
- unsigned int low, high;
- char b[3];
if (fgets(buf, sizeof(buf), f) == NULL)
break;
/* XXXX020 track full country name. */
- if (sscanf(buf,"%u,%u,%2s", &low, &high, b) == 3) {
- geoip_add_entry(low, high, b);
- } else if (sscanf(buf,"\"%u\",\"%u\",\"%2s\",", &low, &high, b) == 3) {
- geoip_add_entry(low, high, b);
- } else {
- log_warn(LD_GENERAL, "Unable to parse line from GEOIP file: %s",
- escaped(buf));
- }
+ geoip_parse_entry(buf);
}
/*XXXX020 abort and return -1 if no entries/illformed?*/
fclose(f);
@@ -105,6 +155,11 @@
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)
{
@@ -115,12 +170,15 @@
return ent ? ent->country : -1;
}
+/** Return the number of countries recognized by the GEOIP database. */
int
geoip_get_n_countries(void)
{
return 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)
{
@@ -130,28 +188,35 @@
return "??";
}
+/** Return true iff we have loaded a GeoIP database.*/
int
geoip_is_loaded(void)
{
return geoip_countries != NULL && geoip_entries != NULL;
}
-/** DOCDOC */
+/** 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;
} clientmap_entry_t;
+/** 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)
{
@@ -163,7 +228,8 @@
HT_GENERATE(clientmap, clientmap_entry_t, node, clientmap_entry_hash,
clientmap_entries_eq, 0.6, malloc, realloc, free);
-/** DOCDOC */
+/** 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(uint32_t addr, time_t now)
{
@@ -185,6 +251,8 @@
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)
{
@@ -197,6 +265,7 @@
}
}
+/** Forget about all clients that haven't connected since <b>cutoff</b>. */
void
geoip_remove_old_clients(time_t cutoff)
{
@@ -207,16 +276,29 @@
client_history_starts = cutoff;
}
+/** Do not mention any country from which fewer than this number of IPs have
+ * connected. This avoids reporting information that could deanonymize
+ * users. */
#define MIN_IPS_TO_NOTE_COUNTRY 8
+/** 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 16
+/** When reporting geoip data about countries, round down 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;
}
+/** 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)
{
@@ -263,6 +345,7 @@
return result;
}
+/** Helper used to implement GETINFO ip-to-country/... controller command. */
int
getinfo_helper_geoip(control_connection_t *control_conn,
const char *question, char **answer)
@@ -282,8 +365,9 @@
return 0;
}
-void
-geoip_free_all(void)
+/** 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));
@@ -295,17 +379,23 @@
SMARTLIST_FOREACH(geoip_entries, geoip_entry_t *, ent, tor_free(ent));
smartlist_free(geoip_entries);
}
- {
- 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);
- }
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();
+}
+
Modified: tor/trunk/src/or/or.h
===================================================================
--- tor/trunk/src/or/or.h 2007-12-18 20:41:48 UTC (rev 12855)
+++ tor/trunk/src/or/or.h 2007-12-18 21:27:08 UTC (rev 12856)
@@ -2317,7 +2317,7 @@
/** DOCDOC here and in tor.1 */
int BridgeRecordUsageByCountry;
- char *GEOIPFile;
+ char *GeoIPFile;
} or_options_t;
@@ -3199,7 +3199,7 @@
/********************************* geoip.c **************************/
#ifdef GEOIP_PRIVATE
-void geoip_add_entry(uint32_t low, uint32_t high, const char *country);
+int geoip_parse_entry(const char *line);
#endif
int geoip_load_file(const char *filename);
int geoip_get_country_by_ip(uint32_t ipaddr);
Modified: tor/trunk/src/or/test.c
===================================================================
--- tor/trunk/src/or/test.c 2007-12-18 20:41:48 UTC (rev 12855)
+++ tor/trunk/src/or/test.c 2007-12-18 21:27:08 UTC (rev 12856)
@@ -33,6 +33,7 @@
#define CRYPTO_PRIVATE
#define DIRSERV_PRIVATE
#define DIRVOTE_PRIVATE
+#define GEOIP_PRIVATE
#define MEMPOOL_PRIVATE
#define ROUTER_PRIVATE
@@ -3369,6 +3370,66 @@
rend_service_descriptor_free(generated);
}
+static void
+test_geoip(void)
+{
+ int i, j;
+ time_t now = time(NULL);
+ char *s;
+
+ /* Populate the DB a bit. Add these in order, since we can't do the final
+ * 'sort' step. These aren't very good IP addresses, but they're perfectly
+ * fine uint32_t values. */
+ test_eq(0, geoip_parse_entry("10,50,AB"));
+ test_eq(0, geoip_parse_entry("52,90,XY"));
+ test_eq(0, geoip_parse_entry("95,100,AB"));
+ test_eq(0, geoip_parse_entry("\"105\",\"140\",\"ZZ\""));
+ test_eq(0, geoip_parse_entry("\"150\",\"190\",\"XY\""));
+ test_eq(0, geoip_parse_entry("\"200\",\"250\",\"AB\""));
+
+ /* We should have 3 countries: ab, xy, zz. */
+ test_eq(3, geoip_get_n_countries());
+ /* Make sure that country ID actually works. */
+#define NAMEFOR(x) geoip_get_country_name(geoip_get_country_by_ip(x))
+ test_streq("ab", NAMEFOR(32));
+ test_streq("??", NAMEFOR(5));
+ test_streq("??", NAMEFOR(51));
+ test_streq("xy", NAMEFOR(150));
+ test_streq("xy", NAMEFOR(190));
+ test_streq("??", NAMEFOR(2000));
+#undef NAMEFOR
+
+ get_options()->BridgeRelay = 1;
+ get_options()->BridgeRecordUsageByCountry = 1;
+ /* Put 9 observations in AB... */
+ for (i=32; i < 40; ++i)
+ geoip_note_client_seen(i, now);
+ geoip_note_client_seen(225, now);
+ /* and 3 observations in XY, several times. */
+ for (j=0; j < 10; ++j)
+ for (i=52; i < 55; ++i)
+ geoip_note_client_seen(i, now-3600);
+ /* and 17 observations in ZZ... */
+ for (i=110; i < 127; ++i)
+ geoip_note_client_seen(i, now-7200);
+ s = geoip_get_client_history(now+5*24*60*60);
+ test_assert(s);
+ test_streq("ab=8,zz=16", s);
+ tor_free(s);
+
+ /* Now clear out all the zz observations. */
+ geoip_remove_old_clients(now-6000);
+ s = geoip_get_client_history(now+5*24*60*60);
+ test_assert(! s); /* There are only 12 observations left. Not enough to
+ build an answer. Add 4 more in XY... */
+ for (i=55; i < 59; ++i)
+ geoip_note_client_seen(i, now-3600);
+ s = geoip_get_client_history(now+5*24*60*60);
+ test_assert(s);
+ test_streq("ab=8", s);
+ tor_free(s);
+}
+
#define ENT(x) { #x, test_ ## x, 0, 0 }
#define SUBENT(x,y) { #x "/" #y, test_ ## x ## _ ## y, 1, 0 }
@@ -3403,6 +3464,7 @@
ENT(policies),
ENT(rend_fns),
SUBENT(rend_fns, v2),
+ ENT(geoip),
{ NULL, NULL, 0, 0 },
};
More information about the tor-commits
mailing list