+ /**
+ * 2.0-style cloaking function
+ * @param item The item to cloak (part of an IP or hostname)
+ * @param id A unique ID for this type of item (to make it unique if the item matches)
+ * @param len The length of the output. Maximum for MD5 is 16 characters.
+ */
+ std::string SegmentCloak(const std::string& item, char id, int len)
+ {
+ std::string input;
+ input.reserve(key.length() + 3 + item.length());
+ input.append(1, id);
+ input.append(key);
+ input.append(1, '\0'); // null does not terminate a C++ string
+ input.append(item);
+
+ std::string rv = Hash->sum(input).substr(0,len);
+ for(int i=0; i < len; i++)
+ {
+ // this discards 3 bits per byte. We have an
+ // overabundance of bits in the hash output, doesn't
+ // matter which ones we are discarding.
+ rv[i] = base32[rv[i] & 0x1F];
+ }
+ return rv;
+ }
+