It is not a bug to attempt to base32_decode a non-base32 string

(Rationale: it isn't a bug to try this for a base16 or base64
string. It's just a bad input that we're detecting.)

src/common/util_format.c

@@ -88,7 +88,7 @@ base32_decode(char *dest, size_t destlen, const char *src, size_t srclen)
     else if (src[j] > 0x31 && src[j] < 0x38) tmp[j] = src[j] - 0x18;
     else if (src[j] > 0x40 && src[j] < 0x5B) tmp[j] = src[j] - 0x41;
     else {
-      log_warn(LD_BUG, "illegal character in base32 encoded string");
+      log_warn(LD_GENERAL, "illegal character in base32 encoded string");
       tor_free(tmp);
       return -1;
     }