Remove now useless rev counter state file code.

We are not using the state file for rev counters anymore, we just generate them
on the fly!

src/or/hs_service.c

@@ -1763,7 +1763,6 @@ service_desc_schedule_upload(hs_service_descriptor_t *desc,
 /* Update the given descriptor from the given service. The possible update
  * actions includes:
  *    - Picking missing intro points if needed.
- *    - Incrementing the revision counter if needed.
  */
 static void
 update_service_descriptor(hs_service_t *service,
@@ -2338,187 +2337,6 @@ upload_descriptor_to_hsdir(const hs_service_t *service,
   return;
 }
 
-/** Return a newly-allocated string for our state file which contains revision
- *  counter information for <b>desc</b>. The format is:
- *
- *     HidServRevCounter <blinded_pubkey> <rev_counter>
- */
-STATIC char *
-encode_desc_rev_counter_for_state(const hs_service_descriptor_t *desc)
-{
-  char *state_str = NULL;
-  char blinded_pubkey_b64[ED25519_BASE64_LEN+1];
-  uint64_t rev_counter = desc->desc->plaintext_data.revision_counter;
-  const ed25519_public_key_t *blinded_pubkey = &desc->blinded_kp.pubkey;
-
-  /* Turn the blinded key into b64 so that we save it on state */
-  tor_assert(blinded_pubkey);
-  if (ed25519_public_to_base64(blinded_pubkey_b64, blinded_pubkey) < 0) {
-    goto done;
-  }
-
-  /* Format is: <blinded key> <rev counter> */
-  tor_asprintf(&state_str, "%s %" PRIu64, blinded_pubkey_b64, rev_counter);
-
-  log_info(LD_GENERAL, "[!] Adding rev counter %" PRIu64 " for %s!",
-           rev_counter, blinded_pubkey_b64);
-
- done:
-  return state_str;
-}
-
-/** Update HS descriptor revision counters in our state by removing the old
- *  ones and writing down the ones that are currently active. */
-static void
-update_revision_counters_in_state(void)
-{
-  config_line_t *lines = NULL;
-  config_line_t **nextline = &lines;
-  or_state_t *state = get_or_state();
-
-  /* Prepare our state structure with the rev counters */
-  FOR_EACH_SERVICE_BEGIN(service) {
-    FOR_EACH_DESCRIPTOR_BEGIN(service, desc) {
-      /* We don't want to save zero counters */
-      if (desc->desc->plaintext_data.revision_counter == 0) {
-        continue;
-      }
-
-      *nextline = tor_malloc_zero(sizeof(config_line_t));
-      (*nextline)->key = tor_strdup("HidServRevCounter");
-      (*nextline)->value = encode_desc_rev_counter_for_state(desc);
-      nextline = &(*nextline)->next;
-    } FOR_EACH_DESCRIPTOR_END;
-  } FOR_EACH_SERVICE_END;
-
-  /* Remove the old rev counters, and replace them with the new ones */
-  config_free_lines(state->HidServRevCounter);
-  state->HidServRevCounter = lines;
-
-  /* Set the state as dirty since we just edited it */
-  if (!get_options()->AvoidDiskWrites) {
-    or_state_mark_dirty(state, 0);
-  }
-}
-
-/** Scan the string <b>state_line</b> for the revision counter of the service
- *  with <b>blinded_pubkey</b>. Set <b>service_found_out</b> to True if the
- *  line is relevant to this service, and return the cached revision
- *  counter. Else set <b>service_found_out</b> to False. */
-STATIC uint64_t
-check_state_line_for_service_rev_counter(const char *state_line,
-                                    const ed25519_public_key_t *blinded_pubkey,
-                                    int *service_found_out)
-{
-  smartlist_t *items = NULL;
-  int ok;
-  ed25519_public_key_t pubkey_in_state;
-  uint64_t rev_counter = 0;
-
-  tor_assert(service_found_out);
-  tor_assert(state_line);
-  tor_assert(blinded_pubkey);
-
-  /* Assume that the line is not for this service */
-  *service_found_out = 0;
-
-  /* Start parsing the state line */
-  items = smartlist_new();
-  smartlist_split_string(items, state_line, NULL,
-                         SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1);
-  if (smartlist_len(items) < 2) {
-    log_warn(LD_GENERAL, "Incomplete rev counter line. Ignoring.");
-    goto done;
-  }
-
-  char *b64_key_str = smartlist_get(items, 0);
-  char *saved_rev_counter_str = smartlist_get(items, 1);
-
-  /* Parse blinded key to check if it's for this hidden service */
-  if (ed25519_public_from_base64(&pubkey_in_state, b64_key_str) < 0) {
-    log_warn(LD_GENERAL, "Unable to base64 key in revcount line. Ignoring.");
-    goto done;
-  }
-  /* State line not for this hidden service */
-  if (!ed25519_pubkey_eq(&pubkey_in_state, blinded_pubkey)) {
-    goto done;
-  }
-
-  rev_counter = tor_parse_uint64(saved_rev_counter_str,
-                                 10, 0, UINT64_MAX, &ok, NULL);
-  if (!ok) {
-    log_warn(LD_GENERAL, "Unable to parse rev counter. Ignoring.");
-    goto done;
-  }
-
-  /* Since we got this far, the line was for this service */
-  *service_found_out = 1;
-
-  log_info(LD_GENERAL, "Found rev counter for %s: %" PRIu64,
-           b64_key_str, rev_counter);
-
- done:
-  tor_assert(items);
-  SMARTLIST_FOREACH(items, char*, s, tor_free(s));
-  smartlist_free(items);
-
-  return rev_counter;
-}
-
-/** Dig into our state file and find the current revision counter for the
- *  service with blinded key <b>blinded_pubkey</b>. If no revision counter is
- *  found, return 0. */
-static uint64_t
-get_rev_counter_for_service(const ed25519_public_key_t *blinded_pubkey)
-{
-  or_state_t *state = get_or_state();
-  config_line_t *line;
-
-  /* Set default value for rev counters (if not found) to 0 */
-  uint64_t final_rev_counter = 0;
-
-  for (line = state->HidServRevCounter ; line ; line = line->next) {
-    int service_found = 0;
-    uint64_t rev_counter = 0;
-
-    tor_assert(!strcmp(line->key, "HidServRevCounter"));
-
-    /* Scan all the HidServRevCounter lines till we find the line for this
-       service: */
-    rev_counter = check_state_line_for_service_rev_counter(line->value,
-                                                           blinded_pubkey,
-                                                           &service_found);
-    if (service_found) {
-      final_rev_counter = rev_counter;
-      goto done;
-    }
-  }
-
- done:
-  return final_rev_counter;
-}
-
-/** Update the value of the revision counter for <b>hs_desc</b> and save it on
-    our state file. */
-static void
-increment_descriptor_revision_counter(hs_descriptor_t *hs_desc)
-{
-  /* Find stored rev counter if it exists */
-  uint64_t rev_counter =
-    get_rev_counter_for_service(&hs_desc->plaintext_data.blinded_pubkey);
-
-  /* Increment the revision counter of <b>hs_desc</b> so the next update (which
-   * will trigger an upload) will have the right value. We do this at this
-   * stage to only do it once because a descriptor can have many updates before
-   * being uploaded. By doing it at upload, we are sure to only increment by 1
-   * and thus avoid leaking how many operations we made on the descriptor from
-   * the previous one before uploading. */
-  rev_counter++;
-  hs_desc->plaintext_data.revision_counter = rev_counter;
-
-  update_revision_counters_in_state();
-}
-
 /** Set the revision counter in <b>hs_desc</b>. We do this by encrypting a
  *  timestamp using an OPE scheme and using the ciphertext as our revision
  *  counter.
@@ -2664,9 +2482,6 @@ upload_descriptor_to_all(const hs_service_t *service,
               safe_str_client(service->onion_address), fmt_next_time);
   }
 
-  /* Update the revision counter of this descriptor */
-  increment_descriptor_revision_counter(desc->desc);
-
   smartlist_free(responsible_dirs);
   return;
 }

src/or/hs_service.h

@@ -346,19 +346,10 @@ STATIC void build_all_descriptors(time_t now);
 STATIC void update_all_descriptors(time_t now);
 STATIC void run_upload_descriptor_event(time_t now);
 
-STATIC char *
-encode_desc_rev_counter_for_state(const hs_service_descriptor_t *desc);
-
 STATIC void service_descriptor_free_(hs_service_descriptor_t *desc);
 #define service_descriptor_free(d) \
   FREE_AND_NULL(hs_service_descriptor_t, \
                            service_descriptor_free_, (d))
-
-STATIC uint64_t
-check_state_line_for_service_rev_counter(const char *state_line,
-                                    const ed25519_public_key_t *blinded_pubkey,
-                                    int *service_found_out);
-
 STATIC int
 write_address_to_file(const hs_service_t *service, const char *fname_);
 

src/test/test_hs_service.c

@@ -1430,66 +1430,6 @@ test_upload_descriptors(void *arg)
   UNMOCK(get_or_state);
 }
 
-/** Test the functions that save and load HS revision counters to state. */
-static void
-test_revision_counter_state(void *arg)
-{
-  char *state_line_one = NULL;
-  char *state_line_two = NULL;
-
-  hs_service_descriptor_t *desc_one = service_descriptor_new();
-  hs_service_descriptor_t *desc_two = service_descriptor_new();
-
-  (void) arg;
-
-  /* Prepare both descriptors */
-  desc_one->desc->plaintext_data.revision_counter = 42;
-  desc_two->desc->plaintext_data.revision_counter = 240;
-  memset(&desc_one->blinded_kp.pubkey.pubkey, 66,
-         sizeof(desc_one->blinded_kp.pubkey.pubkey));
-  memset(&desc_two->blinded_kp.pubkey.pubkey, 240,
-         sizeof(desc_one->blinded_kp.pubkey.pubkey));
-
-  /* Turn the descriptor rev counters into state lines */
-  state_line_one = encode_desc_rev_counter_for_state(desc_one);
-  tt_str_op(state_line_one, OP_EQ,
-            "QkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkI 42");
-
-  state_line_two = encode_desc_rev_counter_for_state(desc_two);
-  tt_str_op(state_line_two, OP_EQ,
-            "8PDw8PDw8PDw8PDw8PDw8PDw8PDw8PDw8PDw8PDw8PA 240");
-
-  /* Now let's test our state parsing function: */
-  int service_found;
-  uint64_t cached_rev_counter;
-
-  /* First's try with wrong pubkey and check that no service was found */
-  cached_rev_counter =check_state_line_for_service_rev_counter(state_line_one,
-                                                 &desc_two->blinded_kp.pubkey,
-                                                               &service_found);
-  tt_int_op(service_found, OP_EQ, 0);
-  tt_u64_op(cached_rev_counter, OP_EQ, 0);
-
-  /* Now let's try with the right pubkeys */
-  cached_rev_counter =check_state_line_for_service_rev_counter(state_line_one,
-                                                 &desc_one->blinded_kp.pubkey,
-                                                               &service_found);
-  tt_int_op(service_found, OP_EQ, 1);
-  tt_u64_op(cached_rev_counter, OP_EQ, 42);
-
-  cached_rev_counter =check_state_line_for_service_rev_counter(state_line_two,
-                                                 &desc_two->blinded_kp.pubkey,
-                                                               &service_found);
-  tt_int_op(service_found, OP_EQ, 1);
-  tt_u64_op(cached_rev_counter, OP_EQ, 240);
-
- done:
-  tor_free(state_line_one);
-  tor_free(state_line_two);
-  service_descriptor_free(desc_one);
-  service_descriptor_free(desc_two);
-}
-
 /** Global vars used by test_rendezvous1_parsing() */
 static char rend1_payload[RELAY_PAYLOAD_SIZE];
 static size_t rend1_payload_len = 0;
@@ -1643,8 +1583,6 @@ struct testcase_t hs_service_tests[] = {
     NULL, NULL },
   { "upload_descriptors", test_upload_descriptors, TT_FORK,
     NULL, NULL },
-  { "revision_counter_state", test_revision_counter_state, TT_FORK,
-    NULL, NULL },
   { "rendezvous1_parsing", test_rendezvous1_parsing, TT_FORK,
     NULL, NULL },