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nickname.c (1654B)


      1 /* Copyright (c) 2001 Matej Pfajfar.
      2 * Copyright (c) 2001-2004, Roger Dingledine.
      3 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
      4 * Copyright (c) 2007-2021, The Tor Project, Inc. */
      5 /* See LICENSE for licensing information */
      6 
      7 /**
      8 * \file nickname.c
      9 * \brief Check and manipulate relay nicknames.
     10 */
     11 
     12 #include "core/or/or.h"
     13 #include "feature/nodelist/nickname.h"
     14 
     15 /** Return true iff <b>s</b> is a valid server nickname. (That is, a string
     16 * containing between 1 and MAX_NICKNAME_LEN characters from
     17 * LEGAL_NICKNAME_CHARACTERS.) */
     18 int
     19 is_legal_nickname(const char *s)
     20 {
     21  size_t len;
     22  tor_assert(s);
     23  len = strlen(s);
     24  return len > 0 && len <= MAX_NICKNAME_LEN &&
     25    strspn(s,LEGAL_NICKNAME_CHARACTERS) == len;
     26 }
     27 
     28 /** Return true iff <b>s</b> is a valid server nickname or
     29 * hex-encoded identity-key digest. */
     30 int
     31 is_legal_nickname_or_hexdigest(const char *s)
     32 {
     33  if (*s!='$')
     34    return is_legal_nickname(s);
     35  else
     36    return is_legal_hexdigest(s);
     37 }
     38 
     39 /** Return true iff <b>s</b> is a valid hex-encoded identity-key
     40 * digest. (That is, an optional $, followed by 40 hex characters,
     41 * followed by either nothing, or = or ~ followed by a nickname, or
     42 * a character other than =, ~, or a hex character.)
     43 */
     44 int
     45 is_legal_hexdigest(const char *s)
     46 {
     47  size_t len;
     48  tor_assert(s);
     49  if (s[0] == '$') s++;
     50  len = strlen(s);
     51  if (len > HEX_DIGEST_LEN) {
     52    if (s[HEX_DIGEST_LEN] == '=' ||
     53        s[HEX_DIGEST_LEN] == '~') {
     54      if (!is_legal_nickname(s+HEX_DIGEST_LEN+1))
     55        return 0;
     56    } else {
     57      return 0;
     58    }
     59  }
     60  return (len >= HEX_DIGEST_LEN &&
     61          strspn(s,HEX_CHARACTERS)==HEX_DIGEST_LEN);
     62 }