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- /* Copyright (c) 2007-2019, The Tor Project, Inc. */
- /* See LICENSE for licensing information */
- /**
- * \file geoip.c
- * \brief Functions related to maintaining an IP-to-country database;
- * to summarizing client connections by country to entry guards, bridges,
- * and directory servers; and for statistics on answering network status
- * requests.
- *
- * There are two main kinds of functions in this module: geoip functions,
- * which map groups of IPv4 and IPv6 addresses to country codes, and
- * statistical functions, which collect statistics about different kinds of
- * per-country usage.
- *
- * The geoip lookup tables are implemented as sorted lists of disjoint address
- * ranges, each mapping to a singleton geoip_country_t. These country objects
- * are also indexed by their names in a hashtable.
- *
- * The tables are populated from disk at startup by the geoip_load_file()
- * function. For more information on the file format they read, see that
- * function. See the scripts and the README file in src/config for more
- * information about how those files are generated.
- *
- * Tor uses GeoIP information in order to implement user requests (such as
- * ExcludeNodes {cc}), and to keep track of how much usage relays are getting
- * for each country.
- */
- #define GEOIP_PRIVATE
- #include "lib/geoip/geoip.h"
- #include "lib/container/map.h"
- #include "lib/container/order.h"
- #include "lib/container/smartlist.h"
- #include "lib/crypt_ops/crypto_digest.h"
- #include "lib/ctime/di_ops.h"
- #include "lib/encoding/binascii.h"
- #include "lib/fs/files.h"
- #include "lib/log/escape.h"
- #include "lib/malloc/malloc.h"
- #include "lib/net/address.h" //????
- #include "lib/net/inaddr.h"
- #include "lib/string/compat_ctype.h"
- #include "lib/string/compat_string.h"
- #include "lib/string/scanf.h"
- #include "lib/string/util_string.h"
- #include <stdio.h>
- #include <string.h>
- static void init_geoip_countries(void);
- /** An entry from the GeoIP IPv4 file: maps an IPv4 range to a country. */
- typedef struct geoip_ipv4_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_ipv4_entry_t;
- /** An entry from the GeoIP IPv6 file: maps an IPv6 range to a country. */
- typedef struct geoip_ipv6_entry_t {
- struct in6_addr ip_low; /**< The lowest IP in the range, in host order */
- struct in6_addr ip_high; /**< The highest IP in the range, in host order */
- intptr_t country; /**< An index into geoip_countries */
- } geoip_ipv6_entry_t;
- /** A list of geoip_country_t */
- 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;
- /** Lists of all known geoip_ipv4_entry_t and geoip_ipv6_entry_t, sorted
- * by their respective ip_low. */
- static smartlist_t *geoip_ipv4_entries = NULL, *geoip_ipv6_entries = NULL;
- /** SHA1 digest of the GeoIP files to include in extra-info descriptors. */
- static char geoip_digest[DIGEST_LEN];
- static char geoip6_digest[DIGEST_LEN];
- /** Return a list of geoip_country_t for all known countries. */
- const smartlist_t *
- geoip_get_countries(void)
- {
- if (geoip_countries == NULL) {
- init_geoip_countries();
- }
- return geoip_countries;
- }
- /** Return the index of the <b>country</b>'s entry in the GeoIP
- * country list if it is a valid 2-letter country code, otherwise
- * return -1. */
- MOCK_IMPL(country_t,
- geoip_get_country,(const char *country))
- {
- void *idxplus1_;
- intptr_t idx;
- idxplus1_ = strmap_get_lc(country_idxplus1_by_lc_code, country);
- if (!idxplus1_)
- return -1;
- idx = ((uintptr_t)idxplus1_)-1;
- return (country_t)idx;
- }
- /** Add an entry to a GeoIP table, mapping all IP addresses between <b>low</b>
- * and <b>high</b>, inclusive, to the 2-letter country code <b>country</b>. */
- static void
- geoip_add_entry(const tor_addr_t *low, const tor_addr_t *high,
- const char *country)
- {
- intptr_t idx;
- void *idxplus1_;
- IF_BUG_ONCE(tor_addr_family(low) != tor_addr_family(high))
- return;
- IF_BUG_ONCE(tor_addr_compare(high, low, CMP_EXACT) < 0)
- return;
- idxplus1_ = strmap_get_lc(country_idxplus1_by_lc_code, country);
- if (!idxplus1_) {
- geoip_country_t *c = tor_malloc_zero(sizeof(geoip_country_t));
- strlcpy(c->countrycode, country, sizeof(c->countrycode));
- tor_strlower(c->countrycode);
- 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;
- }
- {
- geoip_country_t *c = smartlist_get(geoip_countries, (int)idx);
- tor_assert(!strcasecmp(c->countrycode, country));
- }
- if (tor_addr_family(low) == AF_INET) {
- geoip_ipv4_entry_t *ent = tor_malloc_zero(sizeof(geoip_ipv4_entry_t));
- ent->ip_low = tor_addr_to_ipv4h(low);
- ent->ip_high = tor_addr_to_ipv4h(high);
- ent->country = idx;
- smartlist_add(geoip_ipv4_entries, ent);
- } else if (tor_addr_family(low) == AF_INET6) {
- geoip_ipv6_entry_t *ent = tor_malloc_zero(sizeof(geoip_ipv6_entry_t));
- ent->ip_low = *tor_addr_to_in6_assert(low);
- ent->ip_high = *tor_addr_to_in6_assert(high);
- ent->country = idx;
- smartlist_add(geoip_ipv6_entries, ent);
- }
- }
- /** Add an entry to the GeoIP table indicated by <b>family</b>,
- * parsing it from <b>line</b>. The format is as for geoip_load_file(). */
- STATIC int
- geoip_parse_entry(const char *line, sa_family_t family)
- {
- tor_addr_t low_addr, high_addr;
- char c[3];
- char *country = NULL;
- if (!geoip_countries)
- init_geoip_countries();
- if (family == AF_INET) {
- if (!geoip_ipv4_entries)
- geoip_ipv4_entries = smartlist_new();
- } else if (family == AF_INET6) {
- if (!geoip_ipv6_entries)
- geoip_ipv6_entries = smartlist_new();
- } else {
- log_warn(LD_GENERAL, "Unsupported family: %d", family);
- return -1;
- }
- while (TOR_ISSPACE(*line))
- ++line;
- if (*line == '#')
- return 0;
- char buf[512];
- if (family == AF_INET) {
- unsigned int low, high;
- if (tor_sscanf(line,"%u,%u,%2s", &low, &high, c) == 3 ||
- tor_sscanf(line,"\"%u\",\"%u\",\"%2s\",", &low, &high, c) == 3) {
- tor_addr_from_ipv4h(&low_addr, low);
- tor_addr_from_ipv4h(&high_addr, high);
- } else
- goto fail;
- country = c;
- } else { /* AF_INET6 */
- char *low_str, *high_str;
- struct in6_addr low, high;
- char *strtok_state;
- strlcpy(buf, line, sizeof(buf));
- low_str = tor_strtok_r(buf, ",", &strtok_state);
- if (!low_str)
- goto fail;
- high_str = tor_strtok_r(NULL, ",", &strtok_state);
- if (!high_str)
- goto fail;
- country = tor_strtok_r(NULL, "\n", &strtok_state);
- if (!country)
- goto fail;
- if (strlen(country) != 2)
- goto fail;
- if (tor_inet_pton(AF_INET6, low_str, &low) <= 0)
- goto fail;
- tor_addr_from_in6(&low_addr, &low);
- if (tor_inet_pton(AF_INET6, high_str, &high) <= 0)
- goto fail;
- tor_addr_from_in6(&high_addr, &high);
- }
- geoip_add_entry(&low_addr, &high_addr, country);
- return 0;
- fail:
- log_warn(LD_GENERAL, "Unable to parse line from GEOIP %s file: %s",
- family == AF_INET ? "IPv4" : "IPv6", escaped(line));
- return -1;
- }
- /** Sorting helper: return -1, 1, or 0 based on comparison of two
- * geoip_ipv4_entry_t */
- static int
- geoip_ipv4_compare_entries_(const void **_a, const void **_b)
- {
- const geoip_ipv4_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_ipv4_entry_t */
- static int
- geoip_ipv4_compare_key_to_entry_(const void *_key, const void **_member)
- {
- /* No alignment issue here, since _key really is a pointer to uint32_t */
- const uint32_t addr = *(uint32_t *)_key;
- const geoip_ipv4_entry_t *entry = *_member;
- if (addr < entry->ip_low)
- return -1;
- else if (addr > entry->ip_high)
- return 1;
- else
- return 0;
- }
- /** Sorting helper: return -1, 1, or 0 based on comparison of two
- * geoip_ipv6_entry_t */
- static int
- geoip_ipv6_compare_entries_(const void **_a, const void **_b)
- {
- const geoip_ipv6_entry_t *a = *_a, *b = *_b;
- return fast_memcmp(a->ip_low.s6_addr, b->ip_low.s6_addr,
- sizeof(struct in6_addr));
- }
- /** bsearch helper: return -1, 1, or 0 based on comparison of an IPv6
- * (a pointer to a in6_addr) to a geoip_ipv6_entry_t */
- static int
- geoip_ipv6_compare_key_to_entry_(const void *_key, const void **_member)
- {
- const struct in6_addr *addr = (struct in6_addr *)_key;
- const geoip_ipv6_entry_t *entry = *_member;
- if (fast_memcmp(addr->s6_addr, entry->ip_low.s6_addr,
- sizeof(struct in6_addr)) < 0)
- return -1;
- else if (fast_memcmp(addr->s6_addr, entry->ip_high.s6_addr,
- sizeof(struct in6_addr)) > 0)
- return 1;
- else
- return 0;
- }
- /** Set up a new list of geoip countries with no countries (yet) set in it,
- * except for the unknown country.
- */
- static void
- init_geoip_countries(void)
- {
- geoip_country_t *geoip_unresolved;
- geoip_countries = smartlist_new();
- /* Add a geoip_country_t for requests that could not be resolved to a
- * country as first element (index 0) to geoip_countries. */
- geoip_unresolved = tor_malloc_zero(sizeof(geoip_country_t));
- strlcpy(geoip_unresolved->countrycode, "??",
- sizeof(geoip_unresolved->countrycode));
- smartlist_add(geoip_countries, geoip_unresolved);
- country_idxplus1_by_lc_code = strmap_new();
- strmap_set_lc(country_idxplus1_by_lc_code, "??", (void*)(1));
- }
- /** Clear appropriate GeoIP database, based on <b>family</b>, and
- * reload it from the file <b>filename</b>. Return 0 on success, -1 on
- * failure.
- *
- * Recognized line formats for IPv4 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.
- *
- * Recognized line format for IPv6 is:
- * IPV6LOW,IPV6HIGH,CC
- * where IPV6LOW and IPV6HIGH are IPv6 addresses and CC is a country code.
- *
- * It also recognizes, and skips over, blank lines and lines that start
- * with '#' (comments).
- */
- int
- geoip_load_file(sa_family_t family, const char *filename, int severity)
- {
- FILE *f;
- crypto_digest_t *geoip_digest_env = NULL;
- tor_assert(family == AF_INET || family == AF_INET6);
- if (!(f = tor_fopen_cloexec(filename, "r"))) {
- log_fn(severity, LD_GENERAL, "Failed to open GEOIP file %s.",
- filename);
- return -1;
- }
- if (!geoip_countries)
- init_geoip_countries();
- if (family == AF_INET) {
- if (geoip_ipv4_entries) {
- SMARTLIST_FOREACH(geoip_ipv4_entries, geoip_ipv4_entry_t *, e,
- tor_free(e));
- smartlist_free(geoip_ipv4_entries);
- }
- geoip_ipv4_entries = smartlist_new();
- } else { /* AF_INET6 */
- if (geoip_ipv6_entries) {
- SMARTLIST_FOREACH(geoip_ipv6_entries, geoip_ipv6_entry_t *, e,
- tor_free(e));
- smartlist_free(geoip_ipv6_entries);
- }
- geoip_ipv6_entries = smartlist_new();
- }
- geoip_digest_env = crypto_digest_new();
- log_notice(LD_GENERAL, "Parsing GEOIP %s file %s.",
- (family == AF_INET) ? "IPv4" : "IPv6", filename);
- while (!feof(f)) {
- char buf[512];
- if (fgets(buf, (int)sizeof(buf), f) == NULL)
- break;
- crypto_digest_add_bytes(geoip_digest_env, buf, strlen(buf));
- /* FFFF track full country name. */
- geoip_parse_entry(buf, family);
- }
- /*XXXX abort and return -1 if no entries/illformed?*/
- fclose(f);
- /* Sort list and remember file digests so that we can include it in
- * our extra-info descriptors. */
- if (family == AF_INET) {
- smartlist_sort(geoip_ipv4_entries, geoip_ipv4_compare_entries_);
- crypto_digest_get_digest(geoip_digest_env, geoip_digest, DIGEST_LEN);
- } else {
- /* AF_INET6 */
- smartlist_sort(geoip_ipv6_entries, geoip_ipv6_compare_entries_);
- crypto_digest_get_digest(geoip_digest_env, geoip6_digest, DIGEST_LEN);
- }
- crypto_digest_free(geoip_digest_env);
- return 0;
- }
- /** Given an IP address in host order, return a number representing the
- * country to which that address belongs, -1 for "No geoip information
- * available", or 0 for the 'unknown country'. 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_ipv4(uint32_t ipaddr)
- {
- geoip_ipv4_entry_t *ent;
- if (!geoip_ipv4_entries)
- return -1;
- ent = smartlist_bsearch(geoip_ipv4_entries, &ipaddr,
- geoip_ipv4_compare_key_to_entry_);
- return ent ? (int)ent->country : 0;
- }
- /** Given an IPv6 address, return a number representing the country to
- * which that address belongs, -1 for "No geoip information available", or
- * 0 for the 'unknown country'. 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_ipv6(const struct in6_addr *addr)
- {
- geoip_ipv6_entry_t *ent;
- if (!geoip_ipv6_entries)
- return -1;
- ent = smartlist_bsearch(geoip_ipv6_entries, addr,
- geoip_ipv6_compare_key_to_entry_);
- return ent ? (int)ent->country : 0;
- }
- /** Given an IP address, return a number representing the country to which
- * that address belongs, -1 for "No geoip information available", or 0 for
- * the 'unknown country'. The return value will always be less than
- * geoip_get_n_countries(). To decode it, call geoip_get_country_name().
- */
- MOCK_IMPL(int,
- geoip_get_country_by_addr,(const tor_addr_t *addr))
- {
- if (tor_addr_family(addr) == AF_INET) {
- return geoip_get_country_by_ipv4(tor_addr_to_ipv4h(addr));
- } else if (tor_addr_family(addr) == AF_INET6) {
- return geoip_get_country_by_ipv6(tor_addr_to_in6(addr));
- } else {
- return -1;
- }
- }
- /** Return the number of countries recognized by the GeoIP country list. */
- MOCK_IMPL(int,
- geoip_get_n_countries,(void))
- {
- if (!geoip_countries)
- init_geoip_countries();
- 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(country_t num)
- {
- if (geoip_countries && num >= 0 && num < smartlist_len(geoip_countries)) {
- geoip_country_t *c = smartlist_get(geoip_countries, num);
- return c->countrycode;
- } else
- return "??";
- }
- /** Return true iff we have loaded a GeoIP database.*/
- MOCK_IMPL(int,
- geoip_is_loaded,(sa_family_t family))
- {
- tor_assert(family == AF_INET || family == AF_INET6);
- if (geoip_countries == NULL)
- return 0;
- if (family == AF_INET)
- return geoip_ipv4_entries != NULL;
- else /* AF_INET6 */
- return geoip_ipv6_entries != NULL;
- }
- /** Return the hex-encoded SHA1 digest of the loaded GeoIP file. The
- * result does not need to be deallocated, but will be overwritten by the
- * next call of hex_str(). */
- const char *
- geoip_db_digest(sa_family_t family)
- {
- tor_assert(family == AF_INET || family == AF_INET6);
- if (family == AF_INET)
- return hex_str(geoip_digest, DIGEST_LEN);
- else /* AF_INET6 */
- return hex_str(geoip6_digest, DIGEST_LEN);
- }
- /** Release all storage held by the GeoIP databases and country list. */
- STATIC void
- clear_geoip_db(void)
- {
- if (geoip_countries) {
- SMARTLIST_FOREACH(geoip_countries, geoip_country_t *, c, tor_free(c));
- smartlist_free(geoip_countries);
- }
- strmap_free(country_idxplus1_by_lc_code, NULL);
- if (geoip_ipv4_entries) {
- SMARTLIST_FOREACH(geoip_ipv4_entries, geoip_ipv4_entry_t *, ent,
- tor_free(ent));
- smartlist_free(geoip_ipv4_entries);
- }
- if (geoip_ipv6_entries) {
- SMARTLIST_FOREACH(geoip_ipv6_entries, geoip_ipv6_entry_t *, ent,
- tor_free(ent));
- smartlist_free(geoip_ipv6_entries);
- }
- geoip_countries = NULL;
- country_idxplus1_by_lc_code = NULL;
- geoip_ipv4_entries = NULL;
- geoip_ipv6_entries = NULL;
- }
- /** Release all storage held in this file. */
- void
- geoip_free_all(void)
- {
- clear_geoip_db();
- memset(geoip_digest, 0, sizeof(geoip_digest));
- memset(geoip6_digest, 0, sizeof(geoip6_digest));
- }
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