prop224: Add hs_config.{c|h} with a refactoring

Add the hs_config.{c|h} files contains everything that the HS subsystem needs
to load and configure services. Ultimately, it should also contain client
functions such as client authorization.

This comes with a big refactoring of rend_config_services() which has now
changed to only configure a single service and it is stripped down of the
common directives which are now part of the generic handler.

This is ground work for prop224 of course but only touches version 2 services
and add XXX note for version 3.

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 97 insertions, 196 deletions

diff --git a/src/or/rendservice.c b/src/or/rendservice.c
index b8e704e54b..695668bf60 100644
--- a/src/or/rendservice.c
+++ b/src/or/rendservice.c
@@ -236,13 +236,18 @@ rend_service_free(rend_service_t *service)
 void
 rend_service_free_all(void)
 {
-  if (!rend_service_list)
-    return;
-
-  SMARTLIST_FOREACH(rend_service_list, rend_service_t*, ptr,
-                    rend_service_free(ptr));
-  smartlist_free(rend_service_list);
-  rend_service_list = NULL;
+  if (rend_service_list) {
+    SMARTLIST_FOREACH(rend_service_list, rend_service_t*, ptr,
+                      rend_service_free(ptr));
+    smartlist_free(rend_service_list);
+    rend_service_list = NULL;
+  }
+  if (rend_service_staging_list) {
+    SMARTLIST_FOREACH(rend_service_staging_list, rend_service_t*, ptr,
+                      rend_service_free(ptr));
+    smartlist_free(rend_service_staging_list);
+    rend_service_staging_list = NULL;
+  }
 }
 
 /* Validate a <b>service</b>. Use the <b>service_list</b> to make sure there
@@ -335,6 +340,7 @@ rend_add_service(smartlist_t *service_list, rend_service_t *service)
   /* We must have a service list, even if it's a temporary one, so we can
    * check for duplicate services */
   if (BUG(!s_list)) {
+    rend_service_free(service);
     return -1;
   }
 
@@ -496,41 +502,6 @@ rend_service_port_config_free(rend_service_port_config_t *p)
   tor_free(p);
 }
 
-/* Check the directory for <b>service</b>, and add the service to
- * <b>service_list</b>, or to the global list if <b>service_list</b> is NULL.
- * Only add the service to the list if <b>validate_only</b> is false.
- * If <b>validate_only</b> is true, free the service.
- * If <b>service</b> is NULL, ignore it, and return 0.
- * Returns 0 on success, and -1 on failure.
- * Takes ownership of <b>service</b>, either freeing it, or adding it to the
- * global service list.
- */
-STATIC int
-rend_service_check_dir_and_add(smartlist_t *service_list,
-                               const or_options_t *options,
-                               rend_service_t *service,
-                               int validate_only)
-{
-  if (!service) {
-    /* It is ok for a service to be NULL, this means there are no services */
-    return 0;
-  }
-
-  if (rend_service_check_private_dir(options, service, !validate_only)
-      < 0) {
-    rend_service_free(service);
-    return -1;
-  }
-
-  smartlist_t *s_list = rend_get_service_list_mutable(service_list);
-  /* We must have a service list, even if it's a temporary one, so we can
-   * check for duplicate services */
-  if (BUG(!s_list)) {
-    return -1;
-  }
-  return rend_add_service(s_list, service);
-}
-
 /* Helper: Actual implementation of the pruning on reload which we've
  * decoupled in order to make the unit test workeable without ugly hacks.
  * Furthermore, this function does NOT free any memory but will nullify the
@@ -657,19 +628,51 @@ rend_service_prune_list(void)
   }
 }
 
-/** Set up rend_service_list, based on the values of HiddenServiceDir and
- * HiddenServicePort in <b>options</b>.  Return 0 on success and -1 on
- * failure.  (If <b>validate_only</b> is set, parse, warn and return as
- * normal, but don't actually change the configured services.)
- */
+/* Copy all the relevant data that the hs_service object contains over to the
+ * rend_service_t object. The reason to do so is because when configuring a
+ * service, we go through a generic handler that creates an hs_service_t
+ * object which so we have to copy the parsed values to a rend service object
+ * which is version 2 specific. */
+static void
+service_shadow_copy(rend_service_t *service, hs_service_t *hs_service)
+{
+  hs_service_config_t *config;
+
+  tor_assert(service);
+  tor_assert(hs_service);
+
+  config = &hs_service->config;
+  service->directory = tor_strdup(config->directory_path);
+  service->dir_group_readable = config->dir_group_readable;
+  service->allow_unknown_ports = config->allow_unknown_ports;
+  service->max_streams_per_circuit = config->max_streams_per_rdv_circuit;
+  service->max_streams_close_circuit = config->max_streams_close_circuit;
+  service->n_intro_points_wanted = config->num_intro_points;
+  /* Switching ownership of the ports to the rend service object. */
+  smartlist_add_all(service->ports, config->ports);
+  smartlist_free(hs_service->config.ports);
+  hs_service->config.ports = NULL;
+}
+
+/* Parse the hidden service configuration starting at <b>line_</b> using the
+ * already configured generic service in <b>hs_service</b>. This function will
+ * translate the service object to a rend_service_t and add it to the
+ * temporary list if valid. If <b>validate_only</b> is set, parse, warn and
+ * return as normal but don't actually add the service to the list. */
 int
-rend_config_services(const or_options_t *options, int validate_only)
+rend_config_service(const config_line_t *line_,
+                    const or_options_t *options,
+                    int validate_only,
+                    hs_service_t *hs_service)
 {
-  config_line_t *line;
+  (void) validate_only;
+  const config_line_t *line;
   rend_service_t *service = NULL;
-  rend_service_port_config_t *portcfg;
-  int ok = 0;
-  int rv = -1;
+
+  /* line_ can be NULL which would mean that the service configuration only
+   * have one line that is the directory directive. */
+  tor_assert(options);
+  tor_assert(hs_service);
 
   /* Use the staging service list so that we can check then do the pruning
    * process using the main list at the end. */
@@ -677,100 +680,23 @@ rend_config_services(const or_options_t *options, int validate_only)
     rend_service_staging_list = smartlist_new();
   }
 
-  for (line = options->RendConfigLines; line; line = line->next) {
+  /* Initialize service. */
+  service = tor_malloc_zero(sizeof(rend_service_t));
+  service->intro_period_started = time(NULL);
+  service->ports = smartlist_new();
+  /* From the hs_service object which has been used to load the generic
+   * options, we'll copy over the useful data to the rend_service_t object. */
+  service_shadow_copy(service, hs_service);
+
+  for (line = line_; line; line = line->next) {
     if (!strcasecmp(line->key, "HiddenServiceDir")) {
-      if (service) {
-        /* Validate and register the service we just finished parsing this
-         * code registers every service except the last one parsed, which is
-         * validated and registered below the loop. */
-        if (rend_validate_service(rend_service_staging_list, service) < 0) {
-          goto free_and_return;
-        }
-        if (rend_service_check_dir_and_add(rend_service_staging_list, options,
-                                           service, validate_only) < 0) {
-          /* The above frees the service on error so nullify the pointer. */
-          service = NULL;
-          goto free_and_return;
-        }
-      }
-      service = tor_malloc_zero(sizeof(rend_service_t));
-      service->directory = tor_strdup(line->value);
-      service->ports = smartlist_new();
-      service->intro_period_started = time(NULL);
-      service->n_intro_points_wanted = NUM_INTRO_POINTS_DEFAULT;
-      continue;
-    }
-    if (!service) {
-      log_warn(LD_CONFIG, "%s with no preceding HiddenServiceDir directive",
-               line->key);
-      goto free_and_return;
+      /* We just hit the next hidden service, stop right now. */
+      break;
     }
-    if (!strcasecmp(line->key, "HiddenServicePort")) {
-      char *err_msg = NULL;
-      portcfg = rend_service_parse_port_config(line->value, " ", &err_msg);
-      if (!portcfg) {
-        if (err_msg)
-          log_warn(LD_CONFIG, "%s", err_msg);
-        tor_free(err_msg);
-        goto free_and_return;
-      }
-      tor_assert(!err_msg);
-      smartlist_add(service->ports, portcfg);
-    } else if (!strcasecmp(line->key, "HiddenServiceAllowUnknownPorts")) {
-      service->allow_unknown_ports = (int)tor_parse_long(line->value,
-                                                        10, 0, 1, &ok, NULL);
-      if (!ok) {
-        log_warn(LD_CONFIG,
-                 "HiddenServiceAllowUnknownPorts should be 0 or 1, not %s",
-                 line->value);
-        goto free_and_return;
-      }
-      log_info(LD_CONFIG,
-               "HiddenServiceAllowUnknownPorts=%d for %s",
-               (int)service->allow_unknown_ports,
-               rend_service_escaped_dir(service));
-    } else if (!strcasecmp(line->key,
-                           "HiddenServiceDirGroupReadable")) {
-        service->dir_group_readable = (int)tor_parse_long(line->value,
-                                                        10, 0, 1, &ok, NULL);
-        if (!ok) {
-            log_warn(LD_CONFIG,
-                     "HiddenServiceDirGroupReadable should be 0 or 1, not %s",
-                     line->value);
-            goto free_and_return;
-        }
-        log_info(LD_CONFIG,
-                 "HiddenServiceDirGroupReadable=%d for %s",
-                 service->dir_group_readable,
-                 rend_service_escaped_dir(service));
-    } else if (!strcasecmp(line->key, "HiddenServiceMaxStreams")) {
-      service->max_streams_per_circuit = (int)tor_parse_long(line->value,
-                                                    10, 0, 65535, &ok, NULL);
-      if (!ok) {
-        log_warn(LD_CONFIG,
-                 "HiddenServiceMaxStreams should be between 0 and %d, not %s",
-                 65535, line->value);
-        goto free_and_return;
-      }
-      log_info(LD_CONFIG,
-               "HiddenServiceMaxStreams=%d for %s",
-               service->max_streams_per_circuit,
-               rend_service_escaped_dir(service));
-    } else if (!strcasecmp(line->key, "HiddenServiceMaxStreamsCloseCircuit")) {
-      service->max_streams_close_circuit = (int)tor_parse_long(line->value,
-                                                        10, 0, 1, &ok, NULL);
-      if (!ok) {
-        log_warn(LD_CONFIG,
-                 "HiddenServiceMaxStreamsCloseCircuit should be 0 or 1, "
-                 "not %s",
-                 line->value);
-        goto free_and_return;
-      }
-      log_info(LD_CONFIG,
-               "HiddenServiceMaxStreamsCloseCircuit=%d for %s",
-               (int)service->max_streams_close_circuit,
-               rend_service_escaped_dir(service));
-    } else if (!strcasecmp(line->key, "HiddenServiceNumIntroductionPoints")) {
+    /* Number of introduction points. */
+    if (!strcasecmp(line->key, "HiddenServiceNumIntroductionPoints")) {
+      int ok = 0;
+      /* Those are specific defaults for version 2. */
       service->n_intro_points_wanted =
         (unsigned int) tor_parse_long(line->value, 10,
                                       0, NUM_INTRO_POINTS_MAX, &ok, NULL);
@@ -779,12 +705,13 @@ rend_config_services(const or_options_t *options, int validate_only)
                  "HiddenServiceNumIntroductionPoints "
                  "should be between %d and %d, not %s",
                  0, NUM_INTRO_POINTS_MAX, line->value);
-        goto free_and_return;
+        goto err;
       }
       log_info(LD_CONFIG, "HiddenServiceNumIntroductionPoints=%d for %s",
-               service->n_intro_points_wanted,
-               rend_service_escaped_dir(service));
-    } else if (!strcasecmp(line->key, "HiddenServiceAuthorizeClient")) {
+               service->n_intro_points_wanted, escaped(service->directory));
+      continue;
+    }
+    if (!strcasecmp(line->key, "HiddenServiceAuthorizeClient")) {
       /* Parse auth type and comma-separated list of client names and add a
        * rend_authorized_client_t for each client to the service's list
        * of authorized clients. */
@@ -794,7 +721,7 @@ rend_config_services(const or_options_t *options, int validate_only)
       if (service->auth_type != REND_NO_AUTH) {
         log_warn(LD_CONFIG, "Got multiple HiddenServiceAuthorizeClient "
                  "lines for a single service.");
-        goto free_and_return;
+        goto err;
       }
       type_names_split = smartlist_new();
       smartlist_split_string(type_names_split, line->value, " ", 0, 2);
@@ -802,7 +729,8 @@ rend_config_services(const or_options_t *options, int validate_only)
         log_warn(LD_BUG, "HiddenServiceAuthorizeClient has no value. This "
                          "should have been prevented when parsing the "
                          "configuration.");
-        goto free_and_return;
+        smartlist_free(type_names_split);
+        goto err;
       }
       authname = smartlist_get(type_names_split, 0);
       if (!strcasecmp(authname, "basic")) {
@@ -816,7 +744,7 @@ rend_config_services(const or_options_t *options, int validate_only)
                  (char *) smartlist_get(type_names_split, 0));
         SMARTLIST_FOREACH(type_names_split, char *, cp, tor_free(cp));
         smartlist_free(type_names_split);
-        goto free_and_return;
+        goto err;
       }
       service->clients = smartlist_new();
       if (smartlist_len(type_names_split) < 2) {
@@ -853,7 +781,7 @@ rend_config_services(const or_options_t *options, int validate_only)
                    client_name, REND_CLIENTNAME_MAX_LEN);
           SMARTLIST_FOREACH(clients, char *, cp, tor_free(cp));
           smartlist_free(clients);
-          goto free_and_return;
+          goto err;
         }
         client = tor_malloc_zero(sizeof(rend_authorized_client_t));
         client->client_name = tor_strdup(client_name);
@@ -875,56 +803,29 @@ rend_config_services(const or_options_t *options, int validate_only)
                  smartlist_len(service->clients),
                  service->auth_type == REND_BASIC_AUTH ? 512 : 16,
                  service->auth_type == REND_BASIC_AUTH ? "basic" : "stealth");
-        goto free_and_return;
-      }
-    } else {
-      tor_assert(!strcasecmp(line->key, "HiddenServiceVersion"));
-      if (strcmp(line->value, "2")) {
-        log_warn(LD_CONFIG,
-                 "The only supported HiddenServiceVersion is 2.");
-        goto free_and_return;
+        goto err;
       }
+      continue;
     }
   }
-  /* Validate the last service that we just parsed. */
-  if (service &&
-      rend_validate_service(rend_service_staging_list, service) < 0) {
-    goto free_and_return;
-  }
-  /* register the final service after we have finished parsing all services
-   * this code only registers the last service, other services are registered
-   * within the loop. It is ok for this service to be NULL, it is ignored. */
-  if (rend_service_check_dir_and_add(rend_service_staging_list, options,
-                                     service, validate_only) < 0) {
-    /* Service object is freed on error so nullify pointer. */
-    service = NULL;
-    goto free_and_return;
+  /* Validate the service just parsed. */
+  if (rend_validate_service(rend_service_staging_list, service) < 0) {
+    /* Service is in the staging list so don't try to free it. */
+    goto err;
   }
-  /* The service is in the staging list so nullify pointer to avoid double
-   * free of this object in case of error because we lost ownership of it at
-   * this point. */
-  service = NULL;
 
-  /* Free the newly added services if validating */
-  if (validate_only) {
-    rv = 0;
-    goto free_and_return;
+  /* Add it to the temporary list which we will use to prune our current
+   * list if any after configuring all services. */
+  if (rend_add_service(rend_service_staging_list, service) < 0) {
+    /* The object has been freed on error already. */
+    service = NULL;
+    goto err;
   }
 
-  /* This could be a reload of configuration so try to prune the main list
-   * using the staging one. And we know we are not in validate mode here.
-   * After this, the main and staging list will point to the right place and
-   * be in a quiescent usable state. */
-  rend_service_prune_list();
-
   return 0;
- free_and_return:
+ err:
   rend_service_free(service);
-  SMARTLIST_FOREACH(rend_service_staging_list, rend_service_t *, ptr,
-                    rend_service_free(ptr));
-  smartlist_free(rend_service_staging_list);
-  rend_service_staging_list = NULL;
-  return rv;
+  return -1;
 }
 
 /** Add the ephemeral service <b>pk</b>/<b>ports</b> if possible, using
@@ -1548,9 +1449,9 @@ rend_service_load_keys(rend_service_t *s)
   char *fname = NULL;
   char buf[128];
 
-  /* Make sure the directory was created and single onion poisoning was
-   * checked before calling this function */
-  if (BUG(rend_service_check_private_dir(get_options(), s, 0) < 0))
+  /* Create the directory if needed which will also poison it in case of
+   * single onion service. */
+  if (rend_service_check_private_dir(get_options(), s, 1) < 0)
     goto err;
 
   /* Load key */