Commit ed0bc85e authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

Merge branch 'ticket28853'

parents bb091da1 3dd1f064

changes/ticket28853

0 → 100644
+3 −0
Original line number Diff line number Diff line 
  o Minor features (performance):

    - Replace parse_short_policy() with a faster implementation, to improve

      microdescriptor parsing time. Closes ticket 28853.

src/core/or/policies.c

+42 −38
Original line number Diff line number Diff line
@@ -2720,7 +2720,7 @@ parse_short_policy(const char *summary) 
  int is_accept;

  int n_entries;

  short_policy_entry_t entries[MAX_EXITPOLICY_SUMMARY_LEN]; /* overkill */

  const char *next;

  char *next;



  if (!strcmpstart(summary, "accept ")) {

    is_accept = 1;
@@ -2735,57 +2735,56 @@ parse_short_policy(const char *summary) 


  n_entries = 0;

  for ( ; *summary; summary = next) {

    const char *comma = strchr(summary, ',');

    unsigned low, high;

    char dummy;

    char ent_buf[32];

    size_t len;



    next = comma ? comma+1 : strchr(summary, '\0');

    len = comma ? (size_t)(comma - summary) : strlen(summary);



    if (n_entries == MAX_EXITPOLICY_SUMMARY_LEN) {

      log_fn(LOG_PROTOCOL_WARN, LD_DIR, "Impossibly long policy summary %s",

             escaped(orig_summary));

      return NULL;

    }



    if (! TOR_ISDIGIT(*summary) || len > (sizeof(ent_buf)-1)) {

      /* unrecognized entry format. skip it. */

      continue;

    unsigned low, high;

    int ok;

    low = (unsigned) tor_parse_ulong(summary, 10, 1, 65535, &ok, &next);

    if (!ok) {

      if (! TOR_ISDIGIT(*summary) || *summary == ',') {

        /* Unrecognized format: skip it. */

        goto skip_ent;

      } else {

        goto bad_ent;

      }

    if (len < 1) {

      /* empty; skip it. */

      /* XXX This happens to be unreachable, since if len==0, then *summary is

       * ',' or '\0', and the TOR_ISDIGIT test above would have failed. */

      continue;

    }



    memcpy(ent_buf, summary, len);

    ent_buf[len] = '\0';



    if (tor_sscanf(ent_buf, "%u-%u%c", &low, &high, &dummy) == 2) {

      if (low<1 || low>65535 || high<1 || high>65535 || low>high) {

        log_fn(LOG_PROTOCOL_WARN, LD_DIR,

               "Found bad entry in policy summary %s", escaped(orig_summary));

        return NULL;

      }

    } else if (tor_sscanf(ent_buf, "%u%c", &low, &dummy) == 1) {

      if (low<1 || low>65535) {

        log_fn(LOG_PROTOCOL_WARN, LD_DIR,

               "Found bad entry in policy summary %s", escaped(orig_summary));

        return NULL;

      }

    switch (*next) {

      case ',':

        ++next;

        /* fall through */

      case '\0':

        high = low;

    } else {

      log_fn(LOG_PROTOCOL_WARN, LD_DIR,"Found bad entry in policy summary %s",

             escaped(orig_summary));

      return NULL;

        break;

      case '-':

        high = (unsigned) tor_parse_ulong(next+1, 10, low, 65535, &ok, &next);

        if (!ok)

          goto bad_ent;



        if (*next == ',')

          ++next;

        else if (*next != '\0')

          goto bad_ent;



        break;

      default:

        goto bad_ent;

    }



    entries[n_entries].min_port = low;

    entries[n_entries].max_port = high;

    n_entries++;



    continue;

  skip_ent:

    next = strchr(next, ',');

    if (!next)

      break;

    ++next;

  }



  if (n_entries == 0) {
@@ -2806,6 +2805,11 @@ parse_short_policy(const char *summary) 
  result->n_entries = n_entries;

  memcpy(result->entries, entries, sizeof(short_policy_entry_t)*n_entries);

  return result;



 bad_ent:

  log_fn(LOG_PROTOCOL_WARN, LD_DIR,"Found bad entry in policy summary %s",

         escaped(orig_summary));

  return NULL;

}



/** Write <b>policy</b> back out into a string. */