make dir parsing robust to invalid but well-formed descriptors (4ba8bc0a) · Commits · The Tor Project / Core / Tor

src/or/connection_or.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -275,6 +275,7 @@ static int connection_or_process_cell_from_inbuf(connection_t *conn) {
		char buf[CELL_NETWORK_SIZE];
		cell_t cell;

		loop:
		log_fn(LOG_DEBUG,"%d: starting, inbuf_datalen %d (%d pending in tls object).",
		conn->s,(int)buf_datalen(conn->inbuf),tor_tls_get_pending_bytes(conn->tls));
		if(buf_datalen(conn->inbuf) < CELL_NETWORK_SIZE) /* entire response available? */
		@@ -282,14 +283,13 @@ static int connection_or_process_cell_from_inbuf(connection_t *conn) {

		connection_fetch_from_buf(buf, CELL_NETWORK_SIZE, conn);

		/* retrieve cell info from buf (create the host-order struct from the network-order string) */
		/* retrieve cell info from buf (create the host-order struct from the
		* network-order string) */
		cell_unpack(&cell, buf);

		command_process_cell(&cell, conn);

		/* CLEAR Shouldn't this be connection_or_process_inbuf at least? Or maybe
		just use a loop? If not, doc why not. */
		return connection_process_inbuf(conn); /* process the remainder of the buffer */
		goto loop; /* process the remainder of the buffer */
		}

		/*

src/or/dirserv.c

+30 −14

Original line number	Diff line number	Diff line
		@@ -108,7 +108,8 @@ dirserv_parse_fingerprint_file(const char *fname)
		return -1;
		}

		/* return 1 if router's identity and nickname match. */
		/* return 1 if router's identity and nickname match,
		* -1 if they don't match, 0 if the nickname is not known. */
		int
		dirserv_router_fingerprint_is_known(const routerinfo_t *router)
		{
		@@ -126,19 +127,19 @@ dirserv_router_fingerprint_is_known(const routerinfo_t *router)
		}

		if (!ent) { /* No such server known */
		log_fn(LOG_WARN,"no fingerprint found for %s",router->nickname);
		log_fn(LOG_INFO,"no fingerprint found for %s",router->nickname);
		return 0;
		}
		if (crypto_pk_get_fingerprint(router->identity_pkey, fp)) {
		log_fn(LOG_WARN,"error computing fingerprint");
		return 0;
		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 0; /* Wrong fingerprint. */
		return -1; /* Wrong fingerprint. */
		}
		}

		@@ -183,15 +184,21 @@ dirserv_free_descriptors()
		n_descriptors = 0;
		}

		/* Return 0 if descriptor added; -1 if descriptor rejected. Updates *desc
		* to point after the descriptor if the descriptor is OK.
		/* Return 0 if descriptor is well-formed; -1 if descriptor is not
		* well-formed. Update *desc to point after the descriptor if the
		* descriptor is well-formed.
		*/
		/* XXX down the road perhaps we should return 1 for accepted, 0 for
		* well-formed but rejected, -1 for not-well-formed. So remote servers
		* can know if their submission was accepted and not just whether it
		* was well-formed. ...Or maybe we shouldn't give them that info?
		*/
		int
		dirserv_add_descriptor(const char **desc)
		{
		descriptor_entry_t **desc_ent_ptr;
		routerinfo_t *ri = NULL;
		int i;
		int i, r;
		char start, end;
		char desc_tmp = NULL, cp;
		size_t desc_len;
		@@ -221,14 +228,23 @@ dirserv_add_descriptor(const char **desc)
		}
		tor_free(desc_tmp);
		/* Okay. Now check whether the fingerprint is recognized. */
		if (!dirserv_router_fingerprint_is_known(ri)) {
		log_fn(LOG_WARN, "Identity is unrecognized for descriptor");
		goto err;
		r = dirserv_router_fingerprint_is_known(ri);
		if(r<1) {
		if(r==0) {
		log_fn(LOG_WARN, "Unknown nickname %s. Not adding.", ri->nickname);
		} else {
		log_fn(LOG_WARN, "Known nickname %s, wrong fingerprint. Not adding.", ri->nickname);
		}
		routerinfo_free(ri);
		*desc = end;
		return 0;
		}
		/* Is there too much clock skew? */
		if (ri->published_on > time(NULL)+ROUTER_ALLOW_SKEW) {
		log_fn(LOG_WARN, "Publication time for nickname %s is too far in the future; possible clock skew.", ri->nickname);
		goto err;
		log_fn(LOG_WARN, "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;
		}
		/* Do we already have an entry for this router? */
		desc_ent_ptr = NULL;
		@@ -244,8 +260,7 @@ dirserv_add_descriptor(const char **desc)
		/* We already have a newer descriptor */
		log_fn(LOG_INFO,"We already have a newer desc for nickname %s. Not adding.",ri->nickname);
		/* This isn't really an error; return. */
		tor_free(desc_tmp);
		if (ri) routerinfo_free(ri);
		routerinfo_free(ri);
		*desc = end;
		return 0;
		}
		@@ -254,6 +269,7 @@ dirserv_add_descriptor(const char **desc)
		} else {
		/* Add this at the end. */
		desc_ent_ptr = &descriptor_list[n_descriptors++];
		/* XXX check if n_descriptors is too big */
		}

		(*desc_ent_ptr) = tor_malloc(sizeof(descriptor_entry_t));