+ if (Connect(Proxy.Host, Proxy.Port, "socks", 1080, ServerFd, TimeOut, Owner) == false)
+ return false;
+
+ /* We implement a very basic SOCKS5 client here complying mostly to RFC1928 expect
+ * for not offering GSSAPI auth which is a must (we only do no or user/pass auth).
+ * We also expect the SOCKS5 server to do hostname lookup (aka socks5h) */
+ std::string const ProxyInfo = URI::SiteOnly(Proxy);
+ Owner->Status(_("Connecting to %s (%s)"),"SOCKS5h proxy",ProxyInfo.c_str());
+ auto const Timeout = Owner->ConfigFindI("TimeOut", 120);
+ #define APT_WriteOrFail(TYPE, DATA, LENGTH) if (TalkToSocksProxy(ServerFd, ProxyInfo, TYPE, true, DATA, LENGTH, Timeout) == false) return false
+ #define APT_ReadOrFail(TYPE, DATA, LENGTH) if (TalkToSocksProxy(ServerFd, ProxyInfo, TYPE, false, DATA, LENGTH, Timeout) == false) return false
+ if (ServerName.Host.length() > 255)
+ return _error->Error("Can't use SOCKS5h as hostname %s is too long!", ServerName.Host.c_str());
+ if (Proxy.User.length() > 255 || Proxy.Password.length() > 255)
+ return _error->Error("Can't use user&pass auth as they are too long (%lu and %lu) for the SOCKS5!", Proxy.User.length(), Proxy.Password.length());
+ if (Proxy.User.empty())
+ {
+ uint8_t greeting[] = { 0x05, 0x01, 0x00 };
+ APT_WriteOrFail("greet-1", greeting, sizeof(greeting));
+ }
+ else
+ {
+ uint8_t greeting[] = { 0x05, 0x02, 0x00, 0x02 };
+ APT_WriteOrFail("greet-2", greeting, sizeof(greeting));
+ }
+ uint8_t greeting[2];
+ APT_ReadOrFail("greet back", greeting, sizeof(greeting));
+ if (greeting[0] != 0x05)
+ return _error->Error("SOCKS proxy %s greets back with wrong version: %d", ProxyInfo.c_str(), greeting[0]);
+ if (greeting[1] == 0x00)
+ ; // no auth has no method-dependent sub-negotiations
+ else if (greeting[1] == 0x02)
+ {
+ if (Proxy.User.empty())
+ return _error->Error("SOCKS proxy %s negotiated user&pass auth, but we had not offered it!", ProxyInfo.c_str());
+ // user&pass auth sub-negotiations are defined by RFC1929
+ std::vector<uint8_t> auth = {{ 0x01, static_cast<uint8_t>(Proxy.User.length()) }};
+ std::copy(Proxy.User.begin(), Proxy.User.end(), std::back_inserter(auth));
+ auth.push_back(static_cast<uint8_t>(Proxy.Password.length()));
+ std::copy(Proxy.Password.begin(), Proxy.Password.end(), std::back_inserter(auth));
+ APT_WriteOrFail("user&pass auth", auth.data(), auth.size());
+ uint8_t authstatus[2];
+ APT_ReadOrFail("auth report", authstatus, sizeof(authstatus));
+ if (authstatus[0] != 0x01)
+ return _error->Error("SOCKS proxy %s auth status response with wrong version: %d", ProxyInfo.c_str(), authstatus[0]);
+ if (authstatus[1] != 0x00)
+ return _error->Error("SOCKS proxy %s reported authorization failure: username or password incorrect? (%d)", ProxyInfo.c_str(), authstatus[1]);
+ }
+ else
+ return _error->Error("SOCKS proxy %s greets back having not found a common authorization method: %d", ProxyInfo.c_str(), greeting[1]);
+ union { uint16_t * i; uint8_t * b; } portu;
+ uint16_t port = htons(static_cast<uint16_t>(ServerName.Port == 0 ? 80 : ServerName.Port));
+ portu.i = &port;
+ std::vector<uint8_t> request = {{ 0x05, 0x01, 0x00, 0x03, static_cast<uint8_t>(ServerName.Host.length()) }};
+ std::copy(ServerName.Host.begin(), ServerName.Host.end(), std::back_inserter(request));
+ request.push_back(portu.b[0]);
+ request.push_back(portu.b[1]);
+ APT_WriteOrFail("request", request.data(), request.size());
+ uint8_t response[4];
+ APT_ReadOrFail("first part of response", response, sizeof(response));
+ if (response[0] != 0x05)
+ return _error->Error("SOCKS proxy %s response with wrong version: %d", ProxyInfo.c_str(), response[0]);
+ if (response[2] != 0x00)
+ return _error->Error("SOCKS proxy %s has unexpected non-zero reserved field value: %d", ProxyInfo.c_str(), response[2]);
+ std::string bindaddr;
+ if (response[3] == 0x01) // IPv4 address
+ {
+ uint8_t ip4port[6];
+ APT_ReadOrFail("IPv4+Port of response", ip4port, sizeof(ip4port));
+ portu.b[0] = ip4port[4];
+ portu.b[1] = ip4port[5];
+ port = ntohs(*portu.i);
+ strprintf(bindaddr, "%d.%d.%d.%d:%d", ip4port[0], ip4port[1], ip4port[2], ip4port[3], port);
+ }
+ else if (response[3] == 0x03) // hostname
+ {
+ uint8_t namelength;
+ APT_ReadOrFail("hostname length of response", &namelength, 1);
+ uint8_t hostname[namelength + 2];
+ APT_ReadOrFail("hostname of response", hostname, sizeof(hostname));
+ portu.b[0] = hostname[namelength];
+ portu.b[1] = hostname[namelength + 1];
+ port = ntohs(*portu.i);
+ hostname[namelength] = '\0';
+ strprintf(bindaddr, "%s:%d", hostname, port);
+ }
+ else if (response[3] == 0x04) // IPv6 address
+ {
+ uint8_t ip6port[18];
+ APT_ReadOrFail("IPv6+port of response", ip6port, sizeof(ip6port));
+ portu.b[0] = ip6port[16];
+ portu.b[1] = ip6port[17];
+ port = ntohs(*portu.i);
+ strprintf(bindaddr, "[%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X:%02X%02X]:%d",
+ ip6port[0], ip6port[1], ip6port[2], ip6port[3], ip6port[4], ip6port[5], ip6port[6], ip6port[7],
+ ip6port[8], ip6port[9], ip6port[10], ip6port[11], ip6port[12], ip6port[13], ip6port[14], ip6port[15],
+ port);
+ }
+ else
+ return _error->Error("SOCKS proxy %s destination address is of unknown type: %d",
+ ProxyInfo.c_str(), response[3]);
+ if (response[1] != 0x00)
+ {
+ char const * errstr = nullptr;
+ auto errcode = response[1];
+ // Tor error reporting can be a bit arcane, lets try to detect & fix it up
+ if (bindaddr == "0.0.0.0:0")
+ {
+ 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;
+ }
+ }
+ return _error->Error("SOCKS proxy %s could not connect to %s (%s) due to: %s (%d)",
+ ProxyInfo.c_str(), ServerName.Host.c_str(), bindaddr.c_str(), errstr, response[1]);
+ }
+ else if (Owner->DebugEnabled())
+ ioprintf(std::clog, "http: SOCKS proxy %s connection established to %s (%s)\n",
+ ProxyInfo.c_str(), ServerName.Host.c_str(), bindaddr.c_str());
+
+ if (WaitFd(ServerFd, true, Timeout) == false)
+ return _error->Error("SOCKS proxy %s reported connection to %s (%s), but timed out",
+ ProxyInfo.c_str(), ServerName.Host.c_str(), bindaddr.c_str());
+ #undef APT_ReadOrFail
+ #undef APT_WriteOrFail