Function LookupSubNet

src/netbase.cpp:533–562

}

bool LookupSubNet(const char* pszName, CSubNet& ret) {
    std::string strSubnet(pszName);
    size_t slash = strSubnet.find_last_of('/');
    std::vector<CNetAddr> vIP;

    std::string strAddress = strSubnet.substr(0, slash);
    if (LookupHost(strAddress.c_str(), vIP, 1, false)) {
        CNetAddr network = vIP[0];
        if (slash != strSubnet.npos) {
            std::string strNetmask = strSubnet.substr(slash + 1);
            int32_t n;
            // IPv4 addresses start at offset 12, and first 12 bytes must match, so just offset n
            if (ParseInt32(strNetmask, &n)) {  // If valid number, assume /24 syntax
                ret = CSubNet(network, n);
                return ret.IsValid();
            } else  // If not a valid number, try full netmask syntax
            {
                // Never allow lookup for netmask
                if (LookupHost(strNetmask.c_str(), vIP, 1, false)) {
                    ret = CSubNet(network, vIP[0]);
                    return ret.IsValid();
                }
            }
        } else {
            ret = CSubNet(network);
            return ret.IsValid();
        }
    }
    return false;
}

void CNetAddr::Init() { memset(ip, 0, sizeof(ip)); }