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- /* Copyright 2001-2004 Roger Dingledine.
- * Copyright 2004 Roger Dingledine, Nick Mathewson. */
- /* See LICENSE for licensing information */
- /* $Id$ */
- const char dirserv_c_id[] = "$Id$";
- #include "or.h"
- /**
- * \file dirserv.c
- * \brief Directory server core implementation.
- **/
- /** How far in the future do we allow a router to get? (seconds) */
- #define ROUTER_ALLOW_SKEW (30*60)
- /** How many seconds do we wait before regenerating the directory? */
- #define DIR_REGEN_SLACK_TIME 10
- /** Do we need to regenerate the directory when someone asks for it? */
- static int the_directory_is_dirty = 1;
- static int runningrouters_is_dirty = 1;
- static int list_server_status(char **running_routers_out,
- char **router_status_out);
- static void directory_remove_unrecognized(void);
- static int dirserv_regenerate_directory(void);
- /* Should be static; exposed for testing */
- void add_fingerprint_to_dir(const char *nickname, const char *fp);
- /************** Fingerprint handling code ************/
- typedef struct fingerprint_entry_t {
- char *nickname;
- char *fingerprint; /**< Stored as HEX_DIGEST_LEN characters, followed by a NUL */
- } fingerprint_entry_t;
- /** List of nickname-\>identity fingerprint mappings for all the routers
- * that we recognize. Used to prevent Sybil attacks. */
- static smartlist_t *fingerprint_list = NULL;
- /** Add the fingerprint <b>fp</b> for the nickname <b>nickname</b> to
- * the global list of recognized identity key fingerprints.
- */
- void /* Should be static; exposed for testing */
- add_fingerprint_to_dir(const char *nickname, const char *fp)
- {
- int i;
- fingerprint_entry_t *ent;
- if (!fingerprint_list)
- fingerprint_list = smartlist_create();
- for (i = 0; i < smartlist_len(fingerprint_list); ++i) {
- ent = smartlist_get(fingerprint_list, i);
- if (!strcasecmp(ent->nickname,nickname)) {
- tor_free(ent->fingerprint);
- ent->fingerprint = tor_strdup(fp);
- return;
- }
- }
- ent = tor_malloc(sizeof(fingerprint_entry_t));
- ent->nickname = tor_strdup(nickname);
- ent->fingerprint = tor_strdup(fp);
- tor_strstrip(ent->fingerprint, " ");
- smartlist_add(fingerprint_list, ent);
- }
- /** Add the nickname and fingerprint for this OR to the recognized list.
- */
- int
- dirserv_add_own_fingerprint(const char *nickname, crypto_pk_env_t *pk)
- {
- char fp[FINGERPRINT_LEN+1];
- if (crypto_pk_get_fingerprint(pk, fp, 0)<0) {
- log_fn(LOG_ERR, "Error computing fingerprint");
- return -1;
- }
- add_fingerprint_to_dir(nickname, fp);
- return 0;
- }
- /** Parse the nickname-\>fingerprint mappings stored in the file named
- * <b>fname</b>. The file format is line-based, with each non-blank
- * holding one nickname, some space, and a fingerprint for that
- * nickname. On success, replace the current fingerprint list with
- * the contents of <b>fname</b> and return 0. On failure, leave the
- * current fingerprint list untouched, and return -1. */
- int
- dirserv_parse_fingerprint_file(const char *fname)
- {
- char *cf;
- char *nickname, *fingerprint;
- smartlist_t *fingerprint_list_new;
- int i, result;
- fingerprint_entry_t *ent;
- struct config_line_t *front=NULL, *list;
- cf = read_file_to_str(fname, 0);
- if (!cf) {
- log_fn(LOG_WARN, "Cannot open fingerprint file %s", fname);
- return -1;
- }
- result = config_get_lines(cf, &front);
- tor_free(cf);
- if (result < 0) {
- log_fn(LOG_WARN, "Error reading from fingerprint file");
- return -1;
- }
- fingerprint_list_new = smartlist_create();
- for (list=front; list; list=list->next) {
- nickname = list->key; fingerprint = list->value;
- if (strlen(nickname) > MAX_NICKNAME_LEN) {
- log(LOG_NOTICE, "Nickname '%s' too long in fingerprint file. Skipping.", nickname);
- continue;
- }
- if (strlen(fingerprint) != FINGERPRINT_LEN ||
- !crypto_pk_check_fingerprint_syntax(fingerprint)) {
- log_fn(LOG_NOTICE, "Invalid fingerprint (nickname '%s', fingerprint %s). Skipping.",
- nickname, fingerprint);
- continue;
- }
- if (0==strcasecmp(nickname, DEFAULT_CLIENT_NICKNAME)) {
- /* If you approved an OR called "client", then clients who use
- * the default nickname could all be rejected. That's no good. */
- log(LOG_NOTICE,
- "Authorizing a nickname '%s' would break many clients; skipping.",
- DEFAULT_CLIENT_NICKNAME);
- continue;
- }
- for (i = 0; i < smartlist_len(fingerprint_list_new); ++i) {
- ent = smartlist_get(fingerprint_list_new, i);
- if (0==strcasecmp(ent->nickname, nickname)) {
- log(LOG_NOTICE, "Duplicate nickname '%s'. Skipping.",nickname);
- break; /* out of the for. the 'if' below means skip to the next line. */
- }
- }
- if (i == smartlist_len(fingerprint_list_new)) { /* not a duplicate */
- ent = tor_malloc(sizeof(fingerprint_entry_t));
- ent->nickname = tor_strdup(nickname);
- ent->fingerprint = tor_strdup(fingerprint);
- tor_strstrip(ent->fingerprint, " ");
- smartlist_add(fingerprint_list_new, ent);
- }
- }
- config_free_lines(front);
- dirserv_free_fingerprint_list();
- fingerprint_list = fingerprint_list_new;
- /* Delete any routers whose fingerprints we no longer recognize */
- directory_remove_unrecognized();
- return 0;
- }
- /** Check whether <b>router</b> has a nickname/identity key combination that
- * we recognize from the fingerprint list. Return 1 if router's
- * identity and nickname match, -1 if we recognize the nickname but
- * the identity key is wrong, and 0 if the nickname is not known. */
- int
- dirserv_router_fingerprint_is_known(const routerinfo_t *router)
- {
- int i, found=0;
- fingerprint_entry_t *ent =NULL;
- char fp[FINGERPRINT_LEN+1];
- if (!fingerprint_list)
- fingerprint_list = smartlist_create();
- log_fn(LOG_DEBUG, "%d fingerprints known.", smartlist_len(fingerprint_list));
- for (i=0;i<smartlist_len(fingerprint_list);++i) {
- ent = smartlist_get(fingerprint_list, i);
- log_fn(LOG_DEBUG,"%s vs %s", router->nickname, ent->nickname);
- if (!strcasecmp(router->nickname,ent->nickname)) {
- found = 1;
- break;
- }
- }
- if (!found) { /* No such server known */
- log_fn(LOG_INFO,"no fingerprint found for '%s'",router->nickname);
- return 0;
- }
- if (crypto_pk_get_fingerprint(router->identity_pkey, fp, 0)) {
- log_fn(LOG_WARN,"error computing fingerprint");
- return -1;
- }
- if (0==strcasecmp(ent->fingerprint, fp)) {
- log_fn(LOG_DEBUG,"good fingerprint for '%s'",router->nickname);
- return 1; /* Right fingerprint. */
- } else {
- log_fn(LOG_WARN,"mismatched fingerprint for '%s'",router->nickname);
- return -1; /* Wrong fingerprint. */
- }
- }
- /** If we are an authoritative dirserver, and the list of approved
- * servers contains one whose identity key digest is <b>digest</b>,
- * return that router's nickname. Otherwise return NULL. */
- const char *dirserv_get_nickname_by_digest(const char *digest)
- {
- char hexdigest[HEX_DIGEST_LEN+1];
- if (!fingerprint_list)
- return NULL;
- tor_assert(digest);
- base16_encode(hexdigest, HEX_DIGEST_LEN+1, digest, DIGEST_LEN);
- SMARTLIST_FOREACH(fingerprint_list, fingerprint_entry_t*, ent,
- { if (!strcasecmp(hexdigest, ent->fingerprint))
- return ent->nickname; } );
- return NULL;
- }
- #if 0
- /** Return true iff any router named <b>nickname</b> with <b>digest</b>
- * is in the verified fingerprint list. */
- static int
- router_nickname_is_approved(const char *nickname, const char *digest)
- {
- const char *n;
- n = dirserv_get_nickname_by_digest(digest);
- if (n && !strcasecmp(n,nickname))
- return 1;
- else
- return 0;
- }
- #endif
- /** Clear the current fingerprint list. */
- void
- dirserv_free_fingerprint_list()
- {
- int i;
- fingerprint_entry_t *ent;
- if (!fingerprint_list)
- return;
- for (i = 0; i < smartlist_len(fingerprint_list); ++i) {
- ent = smartlist_get(fingerprint_list, i);
- tor_free(ent->nickname);
- tor_free(ent->fingerprint);
- tor_free(ent);
- }
- smartlist_free(fingerprint_list);
- fingerprint_list = NULL;
- }
- /*
- * Descriptor list
- */
- /** A directory server's view of a server descriptor. Contains both
- * parsed and unparsed versions. */
- typedef struct descriptor_entry_t {
- char *nickname;
- time_t published;
- size_t desc_len;
- char *descriptor;
- int verified;
- routerinfo_t *router;
- } descriptor_entry_t;
- /** List of all server descriptors that this dirserv is holding. */
- static smartlist_t *descriptor_list = NULL;
- /** Release the storage held by <b>desc</b> */
- static void free_descriptor_entry(descriptor_entry_t *desc)
- {
- tor_free(desc->descriptor);
- tor_free(desc->nickname);
- routerinfo_free(desc->router);
- tor_free(desc);
- }
- /** Release all storage that the dirserv is holding for server
- * descriptors. */
- void
- dirserv_free_descriptors()
- {
- if (!descriptor_list)
- return;
- SMARTLIST_FOREACH(descriptor_list, descriptor_entry_t *, d,
- free_descriptor_entry(d));
- smartlist_clear(descriptor_list);
- }
- /** Parse the server descriptor at *desc and maybe insert it into the
- * list of server descriptors, and (if the descriptor is well-formed)
- * advance *desc immediately past the descriptor's end.
- *
- * Return 1 if descriptor is well-formed and accepted;
- * 0 if well-formed and server is unapproved;
- * -1 if not well-formed or other error.
- */
- int
- dirserv_add_descriptor(const char **desc)
- {
- descriptor_entry_t *ent = NULL;
- routerinfo_t *ri = NULL;
- int i, r, found=-1;
- char *start, *end;
- char *desc_tmp = NULL;
- const char *cp;
- size_t desc_len;
- time_t now;
- int verified=1; /* whether we knew its fingerprint already */
- if (!descriptor_list)
- descriptor_list = smartlist_create();
- start = strstr(*desc, "router ");
- if (!start) {
- log_fn(LOG_WARN, "no 'router' line found. This is not a descriptor.");
- return -1;
- }
- if ((end = strstr(start+6, "\nrouter "))) {
- ++end; /* Include NL. */
- } else if ((end = strstr(start+6, "\ndirectory-signature"))) {
- ++end;
- } else {
- end = start+strlen(start);
- }
- desc_len = end-start;
- cp = desc_tmp = tor_strndup(start, desc_len);
- /* Check: is the descriptor syntactically valid? */
- ri = router_parse_entry_from_string(cp, NULL);
- tor_free(desc_tmp);
- if (!ri) {
- log(LOG_WARN, "Couldn't parse descriptor");
- return -1;
- }
- /* Okay. Now check whether the fingerprint is recognized. */
- r = dirserv_router_fingerprint_is_known(ri);
- if (r==-1) {
- log_fn(LOG_WARN, "Known nickname '%s', wrong fingerprint. Not adding.", ri->nickname);
- routerinfo_free(ri);
- *desc = end;
- return 0;
- }
- if (r==0) {
- char fp[FINGERPRINT_LEN+1];
- log_fn(LOG_INFO, "Unknown nickname '%s' (%s:%d). Adding.",
- ri->nickname, ri->address, ri->or_port);
- if (crypto_pk_get_fingerprint(ri->identity_pkey, fp, 1) < 0) {
- log_fn(LOG_WARN, "Error computing fingerprint for '%s'", ri->nickname);
- } else {
- log_fn(LOG_INFO, "Fingerprint line: %s %s", ri->nickname, fp);
- }
- verified = 0;
- }
- /* Is there too much clock skew? */
- now = time(NULL);
- if (ri->published_on > now+ROUTER_ALLOW_SKEW) {
- log_fn(LOG_NOTICE, "Publication time for nickname '%s' is too far in the future; possible clock skew. Not adding.", ri->nickname);
- routerinfo_free(ri);
- *desc = end;
- return 0;
- }
- if (ri->published_on < now-ROUTER_MAX_AGE) {
- log_fn(LOG_NOTICE, "Publication time for router with nickname '%s' is too far in the past. Not adding.", ri->nickname);
- routerinfo_free(ri);
- *desc = end;
- return 0;
- }
- /* Do we already have an entry for this router? */
- for (i = 0; i < smartlist_len(descriptor_list); ++i) {
- ent = smartlist_get(descriptor_list, i);
- if (!strcasecmp(ri->nickname, ent->nickname)) {
- found = i;
- break;
- }
- }
- if (found >= 0) {
- /* if so, decide whether to update it. */
- if (ent->published >= ri->published_on) {
- /* We already have a newer or equal-time descriptor */
- log_fn(LOG_INFO,"We already have a new enough desc for nickname '%s'. Not adding.",ri->nickname);
- /* This isn't really an error; return success. */
- routerinfo_free(ri);
- *desc = end;
- return verified;
- }
- /* We don't have a newer one; we'll update this one. */
- log_fn(LOG_INFO,"Dirserv updating desc for nickname '%s'",ri->nickname);
- free_descriptor_entry(ent);
- smartlist_del_keeporder(descriptor_list, found);
- } else {
- /* Add at the end. */
- log_fn(LOG_INFO,"Dirserv adding desc for nickname '%s'",ri->nickname);
- }
- ent = tor_malloc(sizeof(descriptor_entry_t));
- ent->nickname = tor_strdup(ri->nickname);
- ent->published = ri->published_on;
- ent->desc_len = desc_len;
- ent->descriptor = tor_strndup(start,desc_len);
- ent->router = ri;
- ent->verified = verified;
- smartlist_add(descriptor_list, ent);
- *desc = end;
- directory_set_dirty();
- return verified;
- }
- /** Remove all descriptors whose nicknames or fingerprints we don't
- * recognize. (Descriptors that used to be good can become
- * unrecognized when we reload the fingerprint list.)
- */
- static void
- directory_remove_unrecognized(void)
- {
- int i;
- descriptor_entry_t *ent;
- if (!descriptor_list)
- descriptor_list = smartlist_create();
- for (i = 0; i < smartlist_len(descriptor_list); ++i) {
- ent = smartlist_get(descriptor_list, i);
- if (dirserv_router_fingerprint_is_known(ent->router)<=0) {
- log(LOG_INFO, "Router '%s' is no longer recognized",
- ent->nickname);
- free_descriptor_entry(ent);
- smartlist_del(descriptor_list, i--);
- }
- }
- }
- /** Mark the directory as <b>dirty</b> -- when we're next asked for a
- * directory, we will rebuild it instead of reusing the most recently
- * generated one.
- */
- void
- directory_set_dirty()
- {
- time_t now = time(NULL);
- if (!the_directory_is_dirty)
- the_directory_is_dirty = now;
- if (!runningrouters_is_dirty)
- runningrouters_is_dirty = now;
- }
- /** Load all descriptors from a directory stored in the string
- * <b>dir</b>.
- */
- int
- dirserv_load_from_directory_string(const char *dir)
- {
- const char *cp = dir;
- while (1) {
- cp = strstr(cp, "\nrouter ");
- if (!cp) break;
- ++cp;
- if (dirserv_add_descriptor(&cp) < 0) {
- return -1;
- }
- --cp; /*Back up to newline.*/
- }
- return 0;
- }
- /**
- * Allocate and return a description of the status of the server <b>desc</b>,
- * for use in a running-routers line (if <b>rr_format</b> is true), or in a
- * router-status line (if <b>rr_format</b> is false. The server is listed
- * as running iff <b>is_live</b> is true.
- */
- static char *
- list_single_server_status(descriptor_entry_t *desc, int is_live,
- int rr_format)
- {
- char buf[MAX_NICKNAME_LEN+HEX_DIGEST_LEN+4]; /* !nickname=$hexdigest\0 */
- char *cp;
- tor_assert(desc);
- tor_assert(desc->router);
- cp = buf;
- if (!is_live) {
- *cp++ = '!';
- }
- if (desc->verified) {
- strlcpy(cp, desc->nickname, sizeof(buf)-(cp-buf));
- cp += strlen(cp);
- if (!rr_format)
- *cp++ = '=';
- }
- if (!desc->verified || !rr_format) {
- *cp++ = '$';
- base16_encode(cp, HEX_DIGEST_LEN+1, desc->router->identity_digest,
- DIGEST_LEN);
- }
- return tor_strdup(buf);
- }
- /** Allocate the contents of a running-routers line and a router-status line,
- * and store them in *<b>running_routers_out</b> and *<b>router_status_out</b>
- * respectively. Return 0 on success, -1 on failure.
- */
- static int
- list_server_status(char **running_routers_out, char **router_status_out)
- {
- /* List of entries in running-routers style: An optional !, then either
- * a nickname or a dollar-prefixed hexdigest. */
- smartlist_t *rr_entries;
- /* List of entries in a router-status style: An optional !, then an optional
- * equals-suffixed nickname, then a dollar-prefixed hexdigest. */
- smartlist_t *rs_entries;
- tor_assert(running_routers_out || router_status_out);
- rr_entries = smartlist_create();
- rs_entries = smartlist_create();
- SMARTLIST_FOREACH(descriptor_list, descriptor_entry_t *, d,
- {
- int is_live;
- connection_t *conn;
- tor_assert(d->router);
- conn = connection_get_by_identity_digest(
- d->router->identity_digest, CONN_TYPE_OR);
- /* Treat a router as alive if
- * - It's me, and I'm not hibernating.
- * or - we're connected to it. */
- is_live = (router_is_me(d->router) && !we_are_hibernating()) ||
- (conn && conn->state == OR_CONN_STATE_OPEN);
- smartlist_add(rr_entries, list_single_server_status(d, is_live, 1));
- smartlist_add(rs_entries, list_single_server_status(d, is_live, 0));
- });
- if (running_routers_out)
- *running_routers_out = smartlist_join_strings(rr_entries, " ", 0,NULL);
- if (router_status_out)
- *router_status_out = smartlist_join_strings(rs_entries, " ", 0,NULL);
- SMARTLIST_FOREACH(rr_entries, char *, cp, tor_free(cp));
- SMARTLIST_FOREACH(rs_entries, char *, cp, tor_free(cp));
- smartlist_free(rr_entries);
- smartlist_free(rs_entries);
- return 0;
- }
- /** Remove any descriptors from the directory that are more than <b>age</b>
- * seconds old.
- */
- void
- dirserv_remove_old_servers(int age)
- {
- int i;
- time_t cutoff;
- descriptor_entry_t *ent;
- if (!descriptor_list)
- descriptor_list = smartlist_create();
- cutoff = time(NULL) - age;
- for (i = 0; i < smartlist_len(descriptor_list); ++i) {
- ent = smartlist_get(descriptor_list, i);
- if (ent->published <= cutoff) {
- /* descriptor_list[i] is too old. Remove it. */
- free_descriptor_entry(ent);
- smartlist_del(descriptor_list, i--);
- directory_set_dirty();
- }
- }
- }
- /** Generate a new directory and write it into a newly allocated string.
- * Point *<b>dir_out</b> to the allocated string. Sign the
- * directory with <b>private_key</b>. Return 0 on success, -1 on
- * failure.
- */
- int
- dirserv_dump_directory_to_string(char **dir_out,
- crypto_pk_env_t *private_key)
- {
- char *cp;
- char *running_routers, *router_status;
- char *identity_pkey; /* Identity key, DER64-encoded. */
- char *recommended_versions;
- char digest[20];
- char signature[128];
- char published[33];
- time_t published_on;
- char *buf = NULL;
- size_t buf_len;
- int i;
- tor_assert(dir_out);
- *dir_out = NULL;
- if (!descriptor_list)
- descriptor_list = smartlist_create();
- if (list_server_status(&running_routers, &router_status))
- return -1;
- /* ASN.1-encode the public key. This is a temporary measure; once
- * everyone is running 0.0.9pre3 or later, we can shift to using a
- * PEM-encoded key instead.
- */
- #if 1
- if (crypto_pk_DER64_encode_public_key(private_key, &identity_pkey)<0) {
- log_fn(LOG_WARN,"write identity_pkey to string failed!");
- return -1;
- }
- #else
- {
- int l;
- if (crypto_pk_write_public_key_to_string(private_key,&identity_pkey,&l)<0) {
- log_fn(LOG_WARN,"write identity_pkey to string failed!");
- return -1;
- }
- }
- #endif
- {
- smartlist_t *versions;
- struct config_line_t *ln;
- versions = smartlist_create();
- for (ln = get_options()->RecommendedVersions; ln; ln = ln->next) {
- smartlist_split_string(versions, ln->value, ",",
- SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
- }
- recommended_versions = smartlist_join_strings(versions,",",0,NULL);
- SMARTLIST_FOREACH(versions,char *,s,tor_free(s));
- smartlist_free(versions);
- }
- dirserv_remove_old_servers(ROUTER_MAX_AGE);
- published_on = time(NULL);
- format_iso_time(published, published_on);
- buf_len = 2048+strlen(recommended_versions)+strlen(running_routers)+
- strlen(router_status);
- SMARTLIST_FOREACH(descriptor_list, descriptor_entry_t *, d,
- buf_len += strlen(d->descriptor));
- buf = tor_malloc(buf_len);
- /* We'll be comparing against buf_len throughout the rest of the
- function, though strictly speaking we shouldn't be able to exceed
- it. This is C, after all, so we may as well check for buffer
- overruns.*/
- tor_snprintf(buf, buf_len,
- "signed-directory\n"
- "published %s\n"
- "recommended-software %s\n"
- "running-routers %s\n"
- "opt router-status %s\n"
- "opt dir-signing-key %s\n\n",
- published, recommended_versions, running_routers, router_status,
- identity_pkey);
- tor_free(running_routers);
- tor_free(router_status);
- tor_free(identity_pkey);
- i = strlen(buf);
- cp = buf+i;
- SMARTLIST_FOREACH(descriptor_list, descriptor_entry_t *, d,
- if (strlcat(buf, d->descriptor, buf_len) >= buf_len)
- goto truncated);
- /* These multiple strlcat calls are inefficient, but dwarfed by the RSA
- signature.
- */
- if (strlcat(buf, "directory-signature ", buf_len) >= buf_len)
- goto truncated;
- if (strlcat(buf, get_options()->Nickname, buf_len) >= buf_len)
- goto truncated;
- if (strlcat(buf, "\n", buf_len) >= buf_len)
- goto truncated;
- if (router_get_dir_hash(buf,digest)) {
- log_fn(LOG_WARN,"couldn't compute digest");
- tor_free(buf);
- return -1;
- }
- if (crypto_pk_private_sign(private_key, signature, digest, 20) < 0) {
- log_fn(LOG_WARN,"couldn't sign digest");
- tor_free(buf);
- return -1;
- }
- log(LOG_DEBUG,"generated directory digest begins with %s",hex_str(digest,4));
- if (strlcat(cp, "-----BEGIN SIGNATURE-----\n", buf_len) >= buf_len)
- goto truncated;
- i = strlen(buf);
- cp = buf+i;
- if (base64_encode(cp, buf_len-i, signature, 128) < 0) {
- log_fn(LOG_WARN,"couldn't base64-encode signature");
- tor_free(buf);
- return -1;
- }
- if (strlcat(buf, "-----END SIGNATURE-----\n", buf_len) >= buf_len)
- goto truncated;
- *dir_out = buf;
- return 0;
- truncated:
- log_fn(LOG_WARN,"tried to exceed string length.");
- tor_free(buf);
- return -1;
- }
- /** Most recently generated encoded signed directory. */
- static char *the_directory = NULL;
- static size_t the_directory_len = 0;
- static char *the_directory_z = NULL;
- static size_t the_directory_z_len = 0;
- typedef struct cached_dir_t {
- char *dir;
- char *dir_z;
- size_t dir_len;
- size_t dir_z_len;
- time_t published;
- } cached_dir_t;
- /* used only by non-auth dirservers */
- static cached_dir_t cached_directory = { NULL, NULL, 0, 0, 0 };
- static cached_dir_t cached_runningrouters = { NULL, NULL, 0, 0, 0 };
- /** If we have no cached directory, or it is older than <b>when</b>, then
- * replace it with <b>directory</b>, published at <b>when</b>.
- */
- void dirserv_set_cached_directory(const char *directory, time_t when,
- int is_running_routers)
- {
- time_t now;
- cached_dir_t *d;
- now = time(NULL);
- d = is_running_routers ? &cached_runningrouters : &cached_directory;
- if (when<=d->published) {
- log_fn(LOG_INFO, "Ignoring old directory; not caching.");
- } else if (when>=now+ROUTER_ALLOW_SKEW) {
- log_fn(LOG_INFO, "Ignoring future directory; not caching.");
- } else if (when>d->published &&
- when<now+ROUTER_ALLOW_SKEW) {
- log_fn(LOG_DEBUG, "Caching directory.");
- tor_free(d->dir);
- d->dir = tor_strdup(directory);
- d->dir_len = strlen(directory);
- tor_free(d->dir_z);
- if (tor_gzip_compress(&(d->dir_z), &(d->dir_z_len), d->dir, d->dir_len,
- ZLIB_METHOD)) {
- log_fn(LOG_WARN,"Error compressing cached directory");
- }
- d->published = when;
- if (!is_running_routers) {
- char filename[512];
- tor_snprintf(filename,sizeof(filename),"%s/cached-directory", get_options()->DataDirectory);
- if (write_str_to_file(filename,cached_directory.dir,0) < 0) {
- log_fn(LOG_NOTICE, "Couldn't write cached directory to disk. Ignoring.");
- }
- }
- }
- }
- /** Set *<b>directory</b> to the most recently generated encoded signed
- * directory, generating a new one as necessary. If not an authoritative
- * directory may return 0 if no directory is yet cached.*/
- size_t dirserv_get_directory(const char **directory, int compress)
- {
- if (!get_options()->AuthoritativeDir) {
- cached_dir_t *d = &cached_directory;
- *directory = compress ? d->dir_z : d->dir;
- if (*directory) {
- return compress ? d->dir_z_len : d->dir_len;
- } else {
- /* no directory yet retrieved */
- return 0;
- }
- }
- if (the_directory_is_dirty &&
- the_directory_is_dirty + DIR_REGEN_SLACK_TIME < time(NULL)) {
- if (dirserv_regenerate_directory())
- return 0;
- } else {
- log(LOG_INFO,"Directory still clean, reusing.");
- }
- *directory = compress ? the_directory_z : the_directory;
- return compress ? the_directory_z_len : the_directory_len;
- }
- /**
- * Generate a fresh directory (authdirservers only.)
- */
- static int dirserv_regenerate_directory(void)
- {
- char *new_directory=NULL;
- if (dirserv_dump_directory_to_string(&new_directory,
- get_identity_key())) {
- log(LOG_WARN, "Error creating directory.");
- tor_free(new_directory);
- return -1;
- }
- tor_free(the_directory);
- the_directory = new_directory;
- the_directory_len = strlen(the_directory);
- log_fn(LOG_INFO,"New directory (size %d):\n%s",(int)the_directory_len,
- the_directory);
- tor_free(the_directory_z);
- if (tor_gzip_compress(&the_directory_z, &the_directory_z_len,
- the_directory, the_directory_len,
- ZLIB_METHOD)) {
- log_fn(LOG_WARN, "Error gzipping directory.");
- return -1;
- }
- /* Now read the directory we just made in order to update our own
- * router lists. This does more signature checking than is strictly
- * necessary, but safe is better than sorry. */
- new_directory = tor_strdup(the_directory);
- /* use a new copy of the dir, since get_dir_from_string scribbles on it */
- if (router_load_routerlist_from_directory(new_directory, get_identity_key(), 1)) {
- log_fn(LOG_ERR, "We just generated a directory we can't parse. Dying.");
- tor_cleanup();
- exit(0);
- }
- tor_free(new_directory);
- the_directory_is_dirty = 0;
- /* Save the directory to disk so we re-load it quickly on startup.
- */
- dirserv_set_cached_directory(the_directory, time(NULL), 0);
- return 0;
- }
- static char *the_runningrouters=NULL;
- static size_t the_runningrouters_len=0;
- static char *the_runningrouters_z=NULL;
- static size_t the_runningrouters_z_len=0;
- /** Replace the current running-routers list with a newly generated one. */
- static int generate_runningrouters(crypto_pk_env_t *private_key)
- {
- char *s=NULL, *cp;
- char *router_status=NULL;
- char digest[DIGEST_LEN];
- char signature[PK_BYTES];
- int i;
- char published[33];
- size_t len;
- time_t published_on;
- char *identity_pkey; /* Identity key, DER64-encoded. */
- if (list_server_status(NULL, &router_status)) {
- goto err;
- }
- /* ASN.1-encode the public key. This is a temporary measure; once
- * everyone is running 0.0.9pre3 or later, we can shift to using a
- * PEM-encoded key instead.
- */
- #if 1
- if (crypto_pk_DER64_encode_public_key(private_key, &identity_pkey)<0) {
- log_fn(LOG_WARN,"write identity_pkey to string failed!");
- goto err;
- }
- #else
- {
- int l;
- if (crypto_pk_write_public_key_to_string(private_key,&identity_pkey,&l)<0) {
- log_fn(LOG_WARN,"write identity_pkey to string failed!");
- goto err;
- }
- }
- #endif
- published_on = time(NULL);
- format_iso_time(published, published_on);
- len = 2048+strlen(router_status);
- s = tor_malloc_zero(len);
- tor_snprintf(s, len, "network-status\n"
- "published %s\n"
- "router-status %s\n"
- "opt dir-signing-key %s\n"
- "directory-signature %s\n"
- "-----BEGIN SIGNATURE-----\n",
- published, router_status, identity_pkey, get_options()->Nickname);
- tor_free(router_status);
- tor_free(identity_pkey);
- if (router_get_runningrouters_hash(s,digest)) {
- log_fn(LOG_WARN,"couldn't compute digest");
- goto err;
- }
- if (crypto_pk_private_sign(private_key, signature, digest, 20) < 0) {
- log_fn(LOG_WARN,"couldn't sign digest");
- goto err;
- }
- i = strlen(s);
- cp = s+i;
- if (base64_encode(cp, len-i, signature, 128) < 0) {
- log_fn(LOG_WARN,"couldn't base64-encode signature");
- goto err;
- }
- if (strlcat(s, "-----END SIGNATURE-----\n", len) >= len) {
- goto err;
- }
- tor_free(the_runningrouters);
- the_runningrouters = s;
- the_runningrouters_len = strlen(s);
- tor_free(the_runningrouters_z);
- if (tor_gzip_compress(&the_runningrouters_z, &the_runningrouters_z_len,
- the_runningrouters, the_runningrouters_len,
- ZLIB_METHOD)) {
- log_fn(LOG_WARN, "Error gzipping runningrouters");
- return -1;
- }
- runningrouters_is_dirty = 0;
- /* We don't cache running-routers to disk, so there's no point in
- * authdirservers caching it. */
- /* dirserv_set_cached_directory(the_runningrouters, time(NULL), 1); */
- return 0;
- err:
- tor_free(s);
- tor_free(router_status);
- return -1;
- }
- /** Set *<b>rr</b> to the most recently generated encoded signed
- * running-routers list, generating a new one as necessary. Return the
- * size of the directory on success, and 0 on failure. */
- size_t dirserv_get_runningrouters(const char **rr, int compress)
- {
- if (!get_options()->AuthoritativeDir) {
- cached_dir_t *d = &cached_runningrouters;
- *rr = compress ? d->dir_z : d->dir;
- if (*rr) {
- return compress ? d->dir_z_len : d->dir_len;
- } else {
- /* no directory yet retrieved */
- return 0;
- }
- }
- if (runningrouters_is_dirty &&
- runningrouters_is_dirty + DIR_REGEN_SLACK_TIME < time(NULL)) {
- if (generate_runningrouters(get_identity_key())) {
- log_fn(LOG_ERR, "Couldn't generate running-routers list?");
- return 0;
- }
- }
- *rr = compress ? the_runningrouters_z : the_runningrouters;
- return compress ? the_runningrouters_z_len : the_runningrouters_len;
- }
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