src/lib/encoding/keyval.c

   1 /* Copyright (c) 2003, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file keyval.c
   8  *
   9  * \brief Handle data encoded as a key=value pair.
  10  **/
  11
  12 #include "orconfig.h"
  13 #include "lib/encoding/keyval.h"
  14 #include "lib/log/escape.h"
  15 #include "lib/log/log.h"
  16 #include "lib/log/util_bug.h"
  17
  18 #include <stdlib.h>
  19 #include <string.h>
  20
  21 /** Return true if <b>string</b> is a valid 'key=[value]' string.
  22  *  "value" is optional, to indicate the empty string. Log at logging
  23  *  <b>severity</b> if something ugly happens. */
  24 int
  25 string_is_key_value(int severity, const char *string)
  26 {
  27   /* position of equal sign in string */
  28   const char *equal_sign_pos = NULL;
  29
  30   tor_assert(string);
  31
  32   if (strlen(string) < 2) { /* "x=" is shortest args string */
  33     tor_log(severity, LD_GENERAL, "'%s' is too short to be a k=v value.",
  34             escaped(string));
  35     return 0;
  36   }
  37
  38   equal_sign_pos = strchr(string, '=');
  39   if (!equal_sign_pos) {
  40     tor_log(severity, LD_GENERAL, "'%s' is not a k=v value.", escaped(string));
  41     return 0;
  42   }
  43
  44   /* validate that the '=' is not in the beginning of the string. */
  45   if (equal_sign_pos == string) {
  46     tor_log(severity, LD_GENERAL, "'%s' is not a valid k=v value.",
  47             escaped(string));
  48     return 0;
  49   }
  50
  51   return 1;
  52 }