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Diffstat (limited to 'src/or/addressmap.c')
| -rw-r--r-- | src/or/addressmap.c | 1156 |
1 files changed, 0 insertions, 1156 deletions
diff --git a/src/or/addressmap.c b/src/or/addressmap.c deleted file mode 100644 index ba78a5f908..0000000000 --- a/src/or/addressmap.c +++ /dev/null @@ -1,1156 +0,0 @@ -/* Copyright (c) 2001 Matej Pfajfar. - * Copyright (c) 2001-2004, Roger Dingledine. - * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. - * Copyright (c) 2007-2018, The Tor Project, Inc. */ -/* See LICENSE for licensing information */ - -/** - * \file addressmap.c - * - * \brief The addressmap module manages the processes by which we rewrite - * addresses in client requess. It handles the MapAddress controller and - * torrc commands, and the TrackHostExits feature, and the client-side DNS - * cache (deprecated). - */ - -#define ADDRESSMAP_PRIVATE - -#include "lib/crypt_ops/crypto_rand.h" - -#include "or/or.h" -#include "or/addressmap.h" -#include "or/circuituse.h" -#include "or/config.h" -#include "or/connection_edge.h" -#include "or/control.h" -#include "or/dns.h" -#include "or/nodelist.h" -#include "or/routerset.h" - -#include "or/entry_connection_st.h" - -/** A client-side struct to remember requests to rewrite addresses - * to new addresses. These structs are stored in the hash table - * "addressmap" below. - * - * There are 5 ways to set an address mapping: - * - A MapAddress command from the controller [permanent] - * - An AddressMap directive in the torrc [permanent] - * - When a TrackHostExits torrc directive is triggered [temporary] - * - When a DNS resolve succeeds [temporary] - * - When a DNS resolve fails [temporary] - * - * When an addressmap request is made but one is already registered, - * the new one is replaced only if the currently registered one has - * no "new_address" (that is, it's in the process of DNS resolve), - * or if the new one is permanent (expires==0 or 1). - * - * (We overload the 'expires' field, using "0" for mappings set via - * the configuration file, "1" for mappings set from the control - * interface, and other values for DNS and TrackHostExit mappings that can - * expire.) - * - * A mapping may be 'wildcarded'. If "src_wildcard" is true, then - * any address that ends with a . followed by the key for this entry will - * get remapped by it. If "dst_wildcard" is also true, then only the - * matching suffix of such addresses will get replaced by new_address. - */ -typedef struct { - char *new_address; - time_t expires; - addressmap_entry_source_bitfield_t source:3; - unsigned src_wildcard:1; - unsigned dst_wildcard:1; - short num_resolve_failures; -} addressmap_entry_t; - -/** Entry for mapping addresses to which virtual address we mapped them to. */ -typedef struct { - char *ipv4_address; - char *ipv6_address; - char *hostname_address; -} virtaddress_entry_t; - -/** A hash table to store client-side address rewrite instructions. */ -static strmap_t *addressmap=NULL; - -/** - * Table mapping addresses to which virtual address, if any, we - * assigned them to. - * - * We maintain the following invariant: if [A,B] is in - * virtaddress_reversemap, then B must be a virtual address, and [A,B] - * must be in addressmap. We do not require that the converse hold: - * if it fails, then we could end up mapping two virtual addresses to - * the same address, which is no disaster. - **/ -static strmap_t *virtaddress_reversemap=NULL; - -/** Initialize addressmap. */ -void -addressmap_init(void) -{ - addressmap = strmap_new(); - virtaddress_reversemap = strmap_new(); -} - -#define addressmap_ent_free(ent) \ - FREE_AND_NULL(addressmap_entry_t, addressmap_ent_free_, (ent)) - -/** Free the memory associated with the addressmap entry <b>_ent</b>. */ -static void -addressmap_ent_free_(addressmap_entry_t *ent) -{ - if (!ent) - return; - - tor_free(ent->new_address); - tor_free(ent); -} - -static void -addressmap_ent_free_void(void *ent) -{ - addressmap_ent_free_(ent); -} - -#define addressmap_virtaddress_ent_free(ent) \ - FREE_AND_NULL(virtaddress_entry_t, addressmap_virtaddress_ent_free_, (ent)) - -/** Free storage held by a virtaddress_entry_t* entry in <b>_ent</b>. */ -static void -addressmap_virtaddress_ent_free_(virtaddress_entry_t *ent) -{ - if (!ent) - return; - tor_free(ent->ipv4_address); - tor_free(ent->ipv6_address); - tor_free(ent->hostname_address); - tor_free(ent); -} - -static void -addressmap_virtaddress_ent_free_void(void *ent) -{ - addressmap_virtaddress_ent_free_(ent); -} - -/** Remove <b>address</b> (which must map to <b>ent</b>) from the - * virtual address map. */ -static void -addressmap_virtaddress_remove(const char *address, addressmap_entry_t *ent) -{ - if (ent && ent->new_address && - address_is_in_virtual_range(ent->new_address)) { - virtaddress_entry_t *ve = - strmap_get(virtaddress_reversemap, ent->new_address); - /*log_fn(LOG_NOTICE,"remove reverse mapping for %s",ent->new_address);*/ - if (ve) { - if (!strcmp(address, ve->ipv4_address)) - tor_free(ve->ipv4_address); - if (!strcmp(address, ve->ipv6_address)) - tor_free(ve->ipv6_address); - if (!strcmp(address, ve->hostname_address)) - tor_free(ve->hostname_address); - if (!ve->ipv4_address && !ve->ipv6_address && !ve->hostname_address) { - tor_free(ve); - strmap_remove(virtaddress_reversemap, ent->new_address); - } - } - } -} - -/** Remove <b>ent</b> (which must be mapped to by <b>address</b>) from the - * client address maps, and then free it. */ -static void -addressmap_ent_remove(const char *address, addressmap_entry_t *ent) -{ - addressmap_virtaddress_remove(address, ent); - addressmap_ent_free(ent); -} - -/** Unregister all TrackHostExits mappings from any address to - * *.exitname.exit. */ -void -clear_trackexithost_mappings(const char *exitname) -{ - char *suffix = NULL; - if (!addressmap || !exitname) - return; - tor_asprintf(&suffix, ".%s.exit", exitname); - tor_strlower(suffix); - - STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { - if (ent->source == ADDRMAPSRC_TRACKEXIT && - !strcmpend(ent->new_address, suffix)) { - addressmap_ent_remove(address, ent); - MAP_DEL_CURRENT(address); - } - } STRMAP_FOREACH_END; - - tor_free(suffix); -} - -/** Remove all TRACKEXIT mappings from the addressmap for which the target - * host is unknown or no longer allowed, or for which the source address - * is no longer in trackexithosts. */ -void -addressmap_clear_excluded_trackexithosts(const or_options_t *options) -{ - const routerset_t *allow_nodes = options->ExitNodes; - const routerset_t *exclude_nodes = options->ExcludeExitNodesUnion_; - - if (!addressmap) - return; - if (routerset_is_empty(allow_nodes)) - allow_nodes = NULL; - if (allow_nodes == NULL && routerset_is_empty(exclude_nodes)) - return; - - STRMAP_FOREACH_MODIFY(addressmap, address, addressmap_entry_t *, ent) { - size_t len; - const char *target = ent->new_address, *dot; - char *nodename; - const node_t *node; - - if (!target) { - /* DNS resolving in progress */ - continue; - } else if (strcmpend(target, ".exit")) { - /* Not a .exit mapping */ - continue; - } else if (ent->source != ADDRMAPSRC_TRACKEXIT) { - /* Not a trackexit mapping. */ - continue; - } - len = strlen(target); - if (len < 6) - continue; /* malformed. */ - dot = target + len - 6; /* dot now points to just before .exit */ - while (dot > target && *dot != '.') - dot--; - if (*dot == '.') dot++; - nodename = tor_strndup(dot, len-5-(dot-target)); - node = node_get_by_nickname(nodename, NNF_NO_WARN_UNNAMED); - tor_free(nodename); - if (!node || - (allow_nodes && !routerset_contains_node(allow_nodes, node)) || - routerset_contains_node(exclude_nodes, node) || - !hostname_in_track_host_exits(options, address)) { - /* We don't know this one, or we want to be rid of it. */ - addressmap_ent_remove(address, ent); - MAP_DEL_CURRENT(address); - } - } STRMAP_FOREACH_END; -} - -/** Return true iff <b>address</b> is one that we are configured to - * automap on resolve according to <b>options</b>. */ -int -addressmap_address_should_automap(const char *address, - const or_options_t *options) -{ - const smartlist_t *suffix_list = options->AutomapHostsSuffixes; - - if (!suffix_list) - return 0; - - SMARTLIST_FOREACH_BEGIN(suffix_list, const char *, suffix) { - if (!strcmp(suffix, ".")) - return 1; - if (!strcasecmpend(address, suffix)) - return 1; - } SMARTLIST_FOREACH_END(suffix); - return 0; -} - -/** Remove all AUTOMAP mappings from the addressmap for which the - * source address no longer matches AutomapHostsSuffixes, which is - * no longer allowed by AutomapHostsOnResolve, or for which the - * target address is no longer in the virtual network. */ -void -addressmap_clear_invalid_automaps(const or_options_t *options) -{ - int clear_all = !options->AutomapHostsOnResolve; - const smartlist_t *suffixes = options->AutomapHostsSuffixes; - - if (!addressmap) - return; - - if (!suffixes) - clear_all = 1; /* This should be impossible, but let's be sure. */ - - STRMAP_FOREACH_MODIFY(addressmap, src_address, addressmap_entry_t *, ent) { - int remove_this = clear_all; - if (ent->source != ADDRMAPSRC_AUTOMAP) - continue; /* not an automap mapping. */ - - if (!remove_this) { - remove_this = ! addressmap_address_should_automap(src_address, options); - } - - if (!remove_this && ! address_is_in_virtual_range(ent->new_address)) - remove_this = 1; - - if (remove_this) { - addressmap_ent_remove(src_address, ent); - MAP_DEL_CURRENT(src_address); - } - } STRMAP_FOREACH_END; -} - -/** Remove all entries from the addressmap that were set via the - * configuration file or the command line. */ -void -addressmap_clear_configured(void) -{ - addressmap_get_mappings(NULL, 0, 0, 0); -} - -/** Remove all entries from the addressmap that are set to expire, ever. */ -void -addressmap_clear_transient(void) -{ - addressmap_get_mappings(NULL, 2, TIME_MAX, 0); -} - -/** Clean out entries from the addressmap cache that were - * added long enough ago that they are no longer valid. - */ -void -addressmap_clean(time_t now) -{ - addressmap_get_mappings(NULL, 2, now, 0); -} - -/** Free all the elements in the addressmap, and free the addressmap - * itself. */ -void -addressmap_free_all(void) -{ - strmap_free(addressmap, addressmap_ent_free_void); - addressmap = NULL; - - strmap_free(virtaddress_reversemap, addressmap_virtaddress_ent_free_void); - virtaddress_reversemap = NULL; -} - -/** Try to find a match for AddressMap expressions that use - * wildcard notation such as '*.c.d *.e.f' (so 'a.c.d' will map to 'a.e.f') or - * '*.c.d a.b.c' (so 'a.c.d' will map to a.b.c). - * Return the matching entry in AddressMap or NULL if no match is found. - * For expressions such as '*.c.d *.e.f', truncate <b>address</b> 'a.c.d' - * to 'a' before we return the matching AddressMap entry. - * - * This function does not handle the case where a pattern of the form "*.c.d" - * matches the address c.d -- that's done by the main addressmap_rewrite - * function. - */ -static addressmap_entry_t * -addressmap_match_superdomains(char *address) -{ - addressmap_entry_t *val; - char *cp; - - cp = address; - while ((cp = strchr(cp, '.'))) { - /* cp now points to a suffix of address that begins with a . */ - val = strmap_get_lc(addressmap, cp+1); - if (val && val->src_wildcard) { - if (val->dst_wildcard) - *cp = '\0'; - return val; - } - ++cp; - } - return NULL; -} - -/** Look at address, and rewrite it until it doesn't want any - * more rewrites; but don't get into an infinite loop. - * Don't write more than maxlen chars into address. Return true if the - * address changed; false otherwise. Set *<b>expires_out</b> to the - * expiry time of the result, or to <b>time_max</b> if the result does - * not expire. - * - * If <b>exit_source_out</b> is non-null, we set it as follows. If we the - * address starts out as a non-exit address, and we remap it to an .exit - * address at any point, then set *<b>exit_source_out</b> to the - * address_entry_source_t of the first such rule. Set *<b>exit_source_out</b> - * to ADDRMAPSRC_NONE if there is no such rewrite, or if the original address - * was a .exit. - */ -int -addressmap_rewrite(char *address, size_t maxlen, - unsigned flags, - time_t *expires_out, - addressmap_entry_source_t *exit_source_out) -{ - addressmap_entry_t *ent; - int rewrites; - time_t expires = TIME_MAX; - addressmap_entry_source_t exit_source = ADDRMAPSRC_NONE; - char *addr_orig = tor_strdup(address); - char *log_addr_orig = NULL; - - /* We use a loop here to limit the total number of rewrites we do, - * so that we can't hit an infinite loop. */ - for (rewrites = 0; rewrites < 16; rewrites++) { - int exact_match = 0; - log_addr_orig = tor_strdup(escaped_safe_str_client(address)); - - /* First check to see if there's an exact match for this address */ - ent = strmap_get(addressmap, address); - - if (!ent || !ent->new_address) { - /* And if we don't have an exact match, try to check whether - * we have a pattern-based match. - */ - ent = addressmap_match_superdomains(address); - } else { - if (ent->src_wildcard && !ent->dst_wildcard && - !strcasecmp(address, ent->new_address)) { - /* This is a rule like "rewrite *.example.com to example.com", and we - * just got "example.com". Instead of calling it an infinite loop, - * call it complete. */ - goto done; - } - exact_match = 1; - } - - if (!ent || !ent->new_address) { - /* We still have no match at all. We're done! */ - goto done; - } - - /* Check wither the flags we were passed tell us not to use this - * mapping. */ - switch (ent->source) { - case ADDRMAPSRC_DNS: - { - sa_family_t f; - tor_addr_t tmp; - f = tor_addr_parse(&tmp, ent->new_address); - if (f == AF_INET && !(flags & AMR_FLAG_USE_IPV4_DNS)) - goto done; - else if (f == AF_INET6 && !(flags & AMR_FLAG_USE_IPV6_DNS)) - goto done; - } - break; - case ADDRMAPSRC_CONTROLLER: - case ADDRMAPSRC_TORRC: - if (!(flags & AMR_FLAG_USE_MAPADDRESS)) - goto done; - break; - case ADDRMAPSRC_AUTOMAP: - if (!(flags & AMR_FLAG_USE_AUTOMAP)) - goto done; - break; - case ADDRMAPSRC_TRACKEXIT: - if (!(flags & AMR_FLAG_USE_TRACKEXIT)) - goto done; - break; - case ADDRMAPSRC_NONE: - default: - log_warn(LD_BUG, "Unknown addrmap source value %d. Ignoring it.", - (int) ent->source); - goto done; - } - - /* Now fill in the address with the new address. That might be via - * appending some new stuff to the end, or via just replacing it. */ - if (ent->dst_wildcard && !exact_match) { - strlcat(address, ".", maxlen); - strlcat(address, ent->new_address, maxlen); - } else { - strlcpy(address, ent->new_address, maxlen); - } - - /* Is this now a .exit address? If so, remember where we got it.*/ - if (!strcmpend(address, ".exit") && - strcmpend(addr_orig, ".exit") && - exit_source == ADDRMAPSRC_NONE) { - exit_source = ent->source; - } - - log_info(LD_APP, "Addressmap: rewriting %s to %s", - log_addr_orig, escaped_safe_str_client(address)); - if (ent->expires > 1 && ent->expires < expires) - expires = ent->expires; - - tor_free(log_addr_orig); - } - log_warn(LD_CONFIG, - "Loop detected: we've rewritten %s 16 times! Using it as-is.", - escaped_safe_str_client(address)); - /* it's fine to rewrite a rewrite, but don't loop forever */ - - done: - tor_free(addr_orig); - tor_free(log_addr_orig); - if (exit_source_out) - *exit_source_out = exit_source; - if (expires_out) - *expires_out = expires; - return (rewrites > 0); -} - -/** If we have a cached reverse DNS entry for the address stored in the - * <b>maxlen</b>-byte buffer <b>address</b> (typically, a dotted quad) then - * rewrite to the cached value and return 1. Otherwise return 0. Set - * *<b>expires_out</b> to the expiry time of the result, or to <b>time_max</b> - * if the result does not expire. */ -int -addressmap_rewrite_reverse(char *address, size_t maxlen, unsigned flags, - time_t *expires_out) -{ - char *s, *cp; - addressmap_entry_t *ent; - int r = 0; - { - sa_family_t f; - tor_addr_t tmp; - f = tor_addr_parse(&tmp, address); - if (f == AF_INET && !(flags & AMR_FLAG_USE_IPV4_DNS)) - return 0; - else if (f == AF_INET6 && !(flags & AMR_FLAG_USE_IPV6_DNS)) - return 0; - /* FFFF we should reverse-map virtual addresses even if we haven't - * enabled DNS cacheing. */ - } - - tor_asprintf(&s, "REVERSE[%s]", address); - ent = strmap_get(addressmap, s); - if (ent) { - cp = tor_strdup(escaped_safe_str_client(ent->new_address)); - log_info(LD_APP, "Rewrote reverse lookup %s -> %s", - escaped_safe_str_client(s), cp); - tor_free(cp); - strlcpy(address, ent->new_address, maxlen); - r = 1; - } - - if (expires_out) - *expires_out = (ent && ent->expires > 1) ? ent->expires : TIME_MAX; - - tor_free(s); - return r; -} - -/** Return 1 if <b>address</b> is already registered, else return 0. If address - * is already registered, and <b>update_expires</b> is non-zero, then update - * the expiry time on the mapping with update_expires if it is a - * mapping created by TrackHostExits. */ -int -addressmap_have_mapping(const char *address, int update_expiry) -{ - addressmap_entry_t *ent; - if (!(ent=strmap_get_lc(addressmap, address))) - return 0; - if (update_expiry && ent->source==ADDRMAPSRC_TRACKEXIT) - ent->expires=time(NULL) + update_expiry; - return 1; -} - -/** Register a request to map <b>address</b> to <b>new_address</b>, - * which will expire on <b>expires</b> (or 0 if never expires from - * config file, 1 if never expires from controller, 2 if never expires - * (virtual address mapping) from the controller.) - * - * <b>new_address</b> should be a newly dup'ed string, which we'll use or - * free as appropriate. We will leave <b>address</b> alone. - * - * If <b>wildcard_addr</b> is true, then the mapping will match any address - * equal to <b>address</b>, or any address ending with a period followed by - * <b>address</b>. If <b>wildcard_addr</b> and <b>wildcard_new_addr</b> are - * both true, the mapping will rewrite addresses that end with - * ".<b>address</b>" into ones that end with ".<b>new_address</b>". - * - * If <b>new_address</b> is NULL, or <b>new_address</b> is equal to - * <b>address</b> and <b>wildcard_addr</b> is equal to - * <b>wildcard_new_addr</b>, remove any mappings that exist from - * <b>address</b>. - * - * It is an error to set <b>wildcard_new_addr</b> if <b>wildcard_addr</b> is - * not set. */ -void -addressmap_register(const char *address, char *new_address, time_t expires, - addressmap_entry_source_t source, - const int wildcard_addr, - const int wildcard_new_addr) -{ - addressmap_entry_t *ent; - - if (wildcard_new_addr) - tor_assert(wildcard_addr); - - ent = strmap_get(addressmap, address); - if (!new_address || (!strcasecmp(address,new_address) && - wildcard_addr == wildcard_new_addr)) { - /* Remove the mapping, if any. */ - tor_free(new_address); - if (ent) { - addressmap_ent_remove(address,ent); - strmap_remove(addressmap, address); - } - return; - } - if (!ent) { /* make a new one and register it */ - ent = tor_malloc_zero(sizeof(addressmap_entry_t)); - strmap_set(addressmap, address, ent); - } else if (ent->new_address) { /* we need to clean up the old mapping. */ - if (expires > 1) { - log_info(LD_APP,"Temporary addressmap ('%s' to '%s') not performed, " - "since it's already mapped to '%s'", - safe_str_client(address), - safe_str_client(new_address), - safe_str_client(ent->new_address)); - tor_free(new_address); - return; - } - if (address_is_in_virtual_range(ent->new_address) && - expires != 2) { - /* XXX This isn't the perfect test; we want to avoid removing - * mappings set from the control interface _as virtual mapping */ - addressmap_virtaddress_remove(address, ent); - } - tor_free(ent->new_address); - } /* else { we have an in-progress resolve with no mapping. } */ - - ent->new_address = new_address; - ent->expires = expires==2 ? 1 : expires; - ent->num_resolve_failures = 0; - ent->source = source; - ent->src_wildcard = wildcard_addr ? 1 : 0; - ent->dst_wildcard = wildcard_new_addr ? 1 : 0; - - log_info(LD_CONFIG, "Addressmap: (re)mapped '%s' to '%s'", - safe_str_client(address), - safe_str_client(ent->new_address)); - control_event_address_mapped(address, ent->new_address, expires, NULL, 1); -} - -/** An attempt to resolve <b>address</b> failed at some OR. - * Increment the number of resolve failures we have on record - * for it, and then return that number. - */ -int -client_dns_incr_failures(const char *address) -{ - addressmap_entry_t *ent = strmap_get(addressmap, address); - if (!ent) { - ent = tor_malloc_zero(sizeof(addressmap_entry_t)); - ent->expires = time(NULL) + MAX_DNS_ENTRY_AGE; - strmap_set(addressmap,address,ent); - } - if (ent->num_resolve_failures < SHRT_MAX) - ++ent->num_resolve_failures; /* don't overflow */ - log_info(LD_APP, "Address %s now has %d resolve failures.", - safe_str_client(address), - ent->num_resolve_failures); - return ent->num_resolve_failures; -} - -/** If <b>address</b> is in the client DNS addressmap, reset - * the number of resolve failures we have on record for it. - * This is used when we fail a stream because it won't resolve: - * otherwise future attempts on that address will only try once. - */ -void -client_dns_clear_failures(const char *address) -{ - addressmap_entry_t *ent = strmap_get(addressmap, address); - if (ent) - ent->num_resolve_failures = 0; -} - -/** Record the fact that <b>address</b> resolved to <b>name</b>. - * We can now use this in subsequent streams via addressmap_rewrite() - * so we can more correctly choose an exit that will allow <b>address</b>. - * - * If <b>exitname</b> is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If <b>ttl</b> is nonnegative, the mapping will be valid for - * <b>ttl</b>seconds; otherwise, we use the default. - */ -static void -client_dns_set_addressmap_impl(entry_connection_t *for_conn, - const char *address, const char *name, - const char *exitname, - int ttl) -{ - char *extendedaddress=NULL, *extendedval=NULL; - (void)for_conn; - - tor_assert(address); - tor_assert(name); - - if (ttl<0) - ttl = DEFAULT_DNS_TTL; - else - ttl = dns_clip_ttl(ttl); - - if (exitname) { - /* XXXX fails to ever get attempts to get an exit address of - * google.com.digest[=~]nickname.exit; we need a syntax for this that - * won't make strict RFC952-compliant applications (like us) barf. */ - tor_asprintf(&extendedaddress, - "%s.%s.exit", address, exitname); - tor_asprintf(&extendedval, - "%s.%s.exit", name, exitname); - } else { - tor_asprintf(&extendedaddress, - "%s", address); - tor_asprintf(&extendedval, - "%s", name); - } - addressmap_register(extendedaddress, extendedval, - time(NULL) + ttl, ADDRMAPSRC_DNS, 0, 0); - tor_free(extendedaddress); -} - -/** Record the fact that <b>address</b> resolved to <b>val</b>. - * We can now use this in subsequent streams via addressmap_rewrite() - * so we can more correctly choose an exit that will allow <b>address</b>. - * - * If <b>exitname</b> is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If <b>ttl</b> is nonnegative, the mapping will be valid for - * <b>ttl</b>seconds; otherwise, we use the default. - */ -void -client_dns_set_addressmap(entry_connection_t *for_conn, - const char *address, - const tor_addr_t *val, - const char *exitname, - int ttl) -{ - tor_addr_t addr_tmp; - char valbuf[TOR_ADDR_BUF_LEN]; - - tor_assert(address); - tor_assert(val); - - if (tor_addr_parse(&addr_tmp, address) >= 0) - return; /* If address was an IP address already, don't add a mapping. */ - - if (tor_addr_family(val) == AF_INET) { - if (! for_conn->entry_cfg.cache_ipv4_answers) - return; - } else if (tor_addr_family(val) == AF_INET6) { - if (! for_conn->entry_cfg.cache_ipv6_answers) - return; - } - - if (! tor_addr_to_str(valbuf, val, sizeof(valbuf), 1)) - return; - - client_dns_set_addressmap_impl(for_conn, address, valbuf, exitname, ttl); -} - -/** Add a cache entry noting that <b>address</b> (ordinarily a dotted quad) - * resolved via a RESOLVE_PTR request to the hostname <b>v</b>. - * - * If <b>exitname</b> is defined, then append the addresses with - * ".exitname.exit" before registering the mapping. - * - * If <b>ttl</b> is nonnegative, the mapping will be valid for - * <b>ttl</b>seconds; otherwise, we use the default. - */ -void -client_dns_set_reverse_addressmap(entry_connection_t *for_conn, - const char *address, const char *v, - const char *exitname, - int ttl) -{ - char *s = NULL; - { - tor_addr_t tmp_addr; - sa_family_t f = tor_addr_parse(&tmp_addr, address); - if ((f == AF_INET && ! for_conn->entry_cfg.cache_ipv4_answers) || - (f == AF_INET6 && ! for_conn->entry_cfg.cache_ipv6_answers)) - return; - } - tor_asprintf(&s, "REVERSE[%s]", address); - client_dns_set_addressmap_impl(for_conn, s, v, exitname, ttl); - tor_free(s); -} - -/* By default, we hand out 127.192.0.1 through 127.254.254.254. - * These addresses should map to localhost, so even if the - * application accidentally tried to connect to them directly (not - * via Tor), it wouldn't get too far astray. - * - * These options are configured by parse_virtual_addr_network(). - */ - -static virtual_addr_conf_t virtaddr_conf_ipv4; -static virtual_addr_conf_t virtaddr_conf_ipv6; - -/** Read a netmask of the form 127.192.0.0/10 from "val", and check whether - * it's a valid set of virtual addresses to hand out in response to MAPADDRESS - * requests. Return 0 on success; set *msg (if provided) to a newly allocated - * string and return -1 on failure. If validate_only is false, sets the - * actual virtual address range to the parsed value. */ -int -parse_virtual_addr_network(const char *val, sa_family_t family, - int validate_only, - char **msg) -{ - const int ipv6 = (family == AF_INET6); - tor_addr_t addr; - maskbits_t bits; - const int max_prefix_bits = ipv6 ? 104 : 16; - virtual_addr_conf_t *conf = ipv6 ? &virtaddr_conf_ipv6 : &virtaddr_conf_ipv4; - - if (!val || val[0] == '\0') { - if (msg) - tor_asprintf(msg, "Value not present (%s) after VirtualAddressNetwork%s", - val?"Empty":"NULL", ipv6?"IPv6":""); - return -1; - } - if (tor_addr_parse_mask_ports(val, 0, &addr, &bits, NULL, NULL) < 0) { - if (msg) - tor_asprintf(msg, "Error parsing VirtualAddressNetwork%s %s", - ipv6?"IPv6":"", val); - return -1; - } - if (tor_addr_family(&addr) != family) { - if (msg) - tor_asprintf(msg, "Incorrect address type for VirtualAddressNetwork%s", - ipv6?"IPv6":""); - return -1; - } -#if 0 - if (port_min != 1 || port_max != 65535) { - if (msg) - tor_asprintf(msg, "Can't specify ports on VirtualAddressNetwork%s", - ipv6?"IPv6":""); - return -1; - } -#endif /* 0 */ - - if (bits > max_prefix_bits) { - if (msg) - tor_asprintf(msg, "VirtualAddressNetwork%s expects a /%d " - "network or larger",ipv6?"IPv6":"", max_prefix_bits); - return -1; - } - - if (validate_only) - return 0; - - tor_addr_copy(&conf->addr, &addr); - conf->bits = bits; - - return 0; -} - -/** - * Return true iff <b>addr</b> is likely to have been returned by - * client_dns_get_unused_address. - **/ -int -address_is_in_virtual_range(const char *address) -{ - tor_addr_t addr; - tor_assert(address); - if (!strcasecmpend(address, ".virtual")) { - return 1; - } else if (tor_addr_parse(&addr, address) >= 0) { - const virtual_addr_conf_t *conf = (tor_addr_family(&addr) == AF_INET6) ? - &virtaddr_conf_ipv6 : &virtaddr_conf_ipv4; - if (tor_addr_compare_masked(&addr, &conf->addr, conf->bits, CMP_EXACT)==0) - return 1; - } - return 0; -} - -/** Return a random address conforming to the virtual address configuration - * in <b>conf</b>. - */ -STATIC void -get_random_virtual_addr(const virtual_addr_conf_t *conf, tor_addr_t *addr_out) -{ - uint8_t tmp[4]; - const uint8_t *addr_bytes; - uint8_t bytes[16]; - const int ipv6 = tor_addr_family(&conf->addr) == AF_INET6; - const int total_bytes = ipv6 ? 16 : 4; - - tor_assert(conf->bits <= total_bytes * 8); - - /* Set addr_bytes to the bytes of the virtual network, in host order */ - if (ipv6) { - addr_bytes = tor_addr_to_in6_addr8(&conf->addr); - } else { - set_uint32(tmp, tor_addr_to_ipv4n(&conf->addr)); - addr_bytes = tmp; - } - - /* Get an appropriate number of random bytes. */ - crypto_rand((char*)bytes, total_bytes); - - /* Now replace the first "conf->bits" bits of 'bytes' with addr_bytes*/ - if (conf->bits >= 8) - memcpy(bytes, addr_bytes, conf->bits / 8); - if (conf->bits & 7) { - uint8_t mask = 0xff >> (conf->bits & 7); - bytes[conf->bits/8] &= mask; - bytes[conf->bits/8] |= addr_bytes[conf->bits/8] & ~mask; - } - - if (ipv6) - tor_addr_from_ipv6_bytes(addr_out, (char*) bytes); - else - tor_addr_from_ipv4n(addr_out, get_uint32(bytes)); - - tor_assert(tor_addr_compare_masked(addr_out, &conf->addr, - conf->bits, CMP_EXACT)==0); -} - -/** Return a newly allocated string holding an address of <b>type</b> - * (one of RESOLVED_TYPE_{IPV4|IPV6|HOSTNAME}) that has not yet been - * mapped, and that is very unlikely to be the address of any real host. - * - * May return NULL if we have run out of virtual addresses. - */ -static char * -addressmap_get_virtual_address(int type) -{ - char buf[64]; - tor_assert(addressmap); - - if (type == RESOLVED_TYPE_HOSTNAME) { - char rand_bytes[10]; - do { - crypto_rand(rand_bytes, sizeof(rand_bytes)); - base32_encode(buf,sizeof(buf),rand_bytes,sizeof(rand_bytes)); - strlcat(buf, ".virtual", sizeof(buf)); - } while (strmap_get(addressmap, buf)); - return tor_strdup(buf); - } else if (type == RESOLVED_TYPE_IPV4 || type == RESOLVED_TYPE_IPV6) { - const int ipv6 = (type == RESOLVED_TYPE_IPV6); - const virtual_addr_conf_t *conf = ipv6 ? - &virtaddr_conf_ipv6 : &virtaddr_conf_ipv4; - - /* Don't try more than 1000 times. This gives us P < 1e-9 for - * failing to get a good address so long as the address space is - * less than ~97.95% full. That's always going to be true under - * sensible circumstances for an IPv6 /10, and it's going to be - * true for an IPv4 /10 as long as we've handed out less than - * 4.08 million addresses. */ - uint32_t attempts = 1000; - - tor_addr_t addr; - - while (attempts--) { - get_random_virtual_addr(conf, &addr); - - if (!ipv6) { - /* Don't hand out any .0 or .255 address. */ - const uint32_t a = tor_addr_to_ipv4h(&addr); - if ((a & 0xff) == 0 || (a & 0xff) == 0xff) - continue; - } - - tor_addr_to_str(buf, &addr, sizeof(buf), 1); - if (!strmap_get(addressmap, buf)) { - /* XXXX This code is to make sure I didn't add an undecorated version - * by mistake. I hope it's needless. */ - char tmp[TOR_ADDR_BUF_LEN]; - tor_addr_to_str(tmp, &addr, sizeof(tmp), 0); - if (strmap_get(addressmap, tmp)) { - // LCOV_EXCL_START - log_warn(LD_BUG, "%s wasn't in the addressmap, but %s was.", - buf, tmp); - continue; - // LCOV_EXCL_STOP - } - - return tor_strdup(buf); - } - } - log_warn(LD_CONFIG, "Ran out of virtual addresses!"); - return NULL; - } else { - // LCOV_EXCL_START - log_warn(LD_BUG, "Called with unsupported address type (%d)", type); - return NULL; - // LCOV_EXCL_STOP - } -} - -/** A controller has requested that we map some address of type - * <b>type</b> to the address <b>new_address</b>. Choose an address - * that is unlikely to be used, and map it, and return it in a newly - * allocated string. If another address of the same type is already - * mapped to <b>new_address</b>, try to return a copy of that address. - * - * The string in <b>new_address</b> may be freed or inserted into a map - * as appropriate. May return NULL if are out of virtual addresses. - **/ -const char * -addressmap_register_virtual_address(int type, char *new_address) -{ - char **addrp; - virtaddress_entry_t *vent; - int vent_needs_to_be_added = 0; - - tor_assert(new_address); - tor_assert(addressmap); - tor_assert(virtaddress_reversemap); - - vent = strmap_get(virtaddress_reversemap, new_address); - if (!vent) { - vent = tor_malloc_zero(sizeof(virtaddress_entry_t)); - vent_needs_to_be_added = 1; - } - - if (type == RESOLVED_TYPE_IPV4) - addrp = &vent->ipv4_address; - else if (type == RESOLVED_TYPE_IPV6) - addrp = &vent->ipv6_address; - else - addrp = &vent->hostname_address; - - if (*addrp) { - addressmap_entry_t *ent = strmap_get(addressmap, *addrp); - if (ent && ent->new_address && - !strcasecmp(new_address, ent->new_address)) { - tor_free(new_address); - tor_assert(!vent_needs_to_be_added); - return *addrp; - } else { - log_warn(LD_BUG, - "Internal confusion: I thought that '%s' was mapped to by " - "'%s', but '%s' really maps to '%s'. This is a harmless bug.", - safe_str_client(new_address), - safe_str_client(*addrp), - safe_str_client(*addrp), - ent?safe_str_client(ent->new_address):"(nothing)"); - } - } - - tor_free(*addrp); - *addrp = addressmap_get_virtual_address(type); - if (!*addrp) { - tor_free(vent); - tor_free(new_address); - return NULL; - } - log_info(LD_APP, "Registering map from %s to %s", *addrp, new_address); - if (vent_needs_to_be_added) - strmap_set(virtaddress_reversemap, new_address, vent); - addressmap_register(*addrp, new_address, 2, ADDRMAPSRC_AUTOMAP, 0, 0); - - /* FFFF register corresponding reverse mapping. */ - -#if 0 - { - /* Try to catch possible bugs */ - addressmap_entry_t *ent; - ent = strmap_get(addressmap, *addrp); - tor_assert(ent); - tor_assert(!strcasecmp(ent->new_address,new_address)); - vent = strmap_get(virtaddress_reversemap, new_address); - tor_assert(vent); - tor_assert(!strcasecmp(*addrp, - (type == RESOLVED_TYPE_IPV4) ? - vent->ipv4_address : vent->hostname_address)); - log_info(LD_APP, "Map from %s to %s okay.", - safe_str_client(*addrp), - safe_str_client(new_address)); - } -#endif /* 0 */ - - return *addrp; -} - -/** Return 1 if <b>address</b> has funny characters in it like colons. Return - * 0 if it's fine, or if we're configured to allow it anyway. <b>client</b> - * should be true if we're using this address as a client; false if we're - * using it as a server. - */ -int -address_is_invalid_destination(const char *address, int client) -{ - if (client) { - if (get_options()->AllowNonRFC953Hostnames) - return 0; - } else { - if (get_options()->ServerDNSAllowNonRFC953Hostnames) - return 0; - } - - /* It might be an IPv6 address! */ - { - tor_addr_t a; - if (tor_addr_parse(&a, address) >= 0) - return 0; - } - - while (*address) { - if (TOR_ISALNUM(*address) || - *address == '-' || - *address == '.' || - *address == '_') /* Underscore is not allowed, but Windows does it - * sometimes, just to thumb its nose at the IETF. */ - ++address; - else - return 1; - } - return 0; -} - -/** Iterate over all address mappings which have expiry times between - * min_expires and max_expires, inclusive. If sl is provided, add an - * "old-addr new-addr expiry" string to sl for each mapping, omitting - * the expiry time if want_expiry is false. If sl is NULL, remove the - * mappings. - */ -void -addressmap_get_mappings(smartlist_t *sl, time_t min_expires, - time_t max_expires, int want_expiry) -{ - strmap_iter_t *iter; - const char *key; - void *val_; - addressmap_entry_t *val; - - if (!addressmap) - addressmap_init(); - - for (iter = strmap_iter_init(addressmap); !strmap_iter_done(iter); ) { - strmap_iter_get(iter, &key, &val_); - val = val_; - if (val->expires >= min_expires && val->expires <= max_expires) { - if (!sl) { - iter = strmap_iter_next_rmv(addressmap,iter); - addressmap_ent_remove(key, val); - continue; - } else if (val->new_address) { - const char *src_wc = val->src_wildcard ? "*." : ""; - const char *dst_wc = val->dst_wildcard ? "*." : ""; - if (want_expiry) { - if (val->expires < 3 || val->expires == TIME_MAX) - smartlist_add_asprintf(sl, "%s%s %s%s NEVER", - src_wc, key, dst_wc, val->new_address); - else { - char isotime[ISO_TIME_LEN+1]; - format_iso_time(isotime, val->expires); - smartlist_add_asprintf(sl, "%s%s %s%s \"%s\"", - src_wc, key, dst_wc, val->new_address, - isotime); - } - } else { - smartlist_add_asprintf(sl, "%s%s %s%s", - src_wc, key, dst_wc, val->new_address); - } - } - } - iter = strmap_iter_next(addressmap,iter); - } -} |