- case 0x01: errstr = "general SOCKS server failure"; Owner->SetFailReason("SOCKS"); break;
- case 0x02: errstr = "connection not allowed by ruleset"; Owner->SetFailReason("SOCKS"); break;
- case 0x03: errstr = "Network unreachable"; Owner->SetFailReason("ConnectionTimedOut"); break;
- case 0x04: errstr = "Host unreachable"; Owner->SetFailReason("ConnectionTimedOut"); break;
- case 0x05: errstr = "Connection refused"; Owner->SetFailReason("ConnectionRefused"); break;
- case 0x06: errstr = "TTL expired"; Owner->SetFailReason("Timeout"); break;
- case 0x07: errstr = "Command not supported"; Owner->SetFailReason("SOCKS"); break;
- case 0x08: errstr = "Address type not supported"; Owner->SetFailReason("SOCKS"); break;
- default: errstr = "Unknown error"; Owner->SetFailReason("SOCKS"); break;
+ auto const lastdot = ServerName.Host.rfind('.');
+ if (lastdot == std::string::npos || ServerName.Host.substr(lastdot) != ".onion")
+ ;
+ else if (errcode == 0x01)
+ {
+ auto const prevdot = ServerName.Host.rfind('.', lastdot - 1);
+ if (lastdot == 16 && prevdot == std::string::npos)
+ ; // valid .onion address
+ else if (prevdot != std::string::npos && (lastdot - prevdot) == 17)
+ ; // valid .onion address with subdomain(s)
+ else
+ {
+ errstr = "Invalid hostname: onion service name must be 16 characters long";
+ Owner->SetFailReason("SOCKS");
+ }
+ }
+ // in all likelihood the service is either down or the address has
+ // a typo and so "Host unreachable" is the better understood error
+ // compared to the technically correct "TLL expired".
+ else if (errcode == 0x06)
+ errcode = 0x04;
+ }
+ if (errstr == nullptr)
+ {
+ switch (errcode)
+ {
+ case 0x01: errstr = "general SOCKS server failure"; Owner->SetFailReason("SOCKS"); break;
+ case 0x02: errstr = "connection not allowed by ruleset"; Owner->SetFailReason("SOCKS"); break;
+ case 0x03: errstr = "Network unreachable"; Owner->SetFailReason("ConnectionTimedOut"); break;
+ case 0x04: errstr = "Host unreachable"; Owner->SetFailReason("ConnectionTimedOut"); break;
+ case 0x05: errstr = "Connection refused"; Owner->SetFailReason("ConnectionRefused"); break;
+ case 0x06: errstr = "TTL expired"; Owner->SetFailReason("Timeout"); break;
+ case 0x07: errstr = "Command not supported"; Owner->SetFailReason("SOCKS"); break;
+ case 0x08: errstr = "Address type not supported"; Owner->SetFailReason("SOCKS"); break;
+ default: errstr = "Unknown error"; Owner->SetFailReason("SOCKS"); break;
+ }