// -*- mode: cpp; mode: fold -*- // Description /*{{{*/ // $Id: connect.cc,v 1.10.2.1 2004/01/16 18:58:50 mdz Exp $ /* ###################################################################### Connect - Replacement connect call This was originally authored by Jason Gunthorpe and is placed in the Public Domain, do with it what you will. ##################################################################### */ /*}}}*/ // Include Files /*{{{*/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include // Internet stuff #include #include #include #include #include "aptmethod.h" #include "connect.h" #include "rfc2553emu.h" #include /*}}}*/ static std::string LastHost; static int LastPort = 0; static struct addrinfo *LastHostAddr = 0; static struct addrinfo *LastUsed = 0; static std::vector SrvRecords; // Set of IP/hostnames that we timed out before or couldn't resolve static std::set bad_addr; // RotateDNS - Select a new server from a DNS rotation /*{{{*/ // --------------------------------------------------------------------- /* This is called during certain errors in order to recover by selecting a new server */ void RotateDNS() { if (LastUsed != 0 && LastUsed->ai_next != 0) LastUsed = LastUsed->ai_next; else LastUsed = LastHostAddr; } /*}}}*/ static bool ConnectionAllowed(char const * const Service, std::string const &Host)/*{{{*/ { if (unlikely(Host.empty())) // the only legal empty host (RFC2782 '.' target) is detected by caller return false; if (APT::String::Endswith(Host, ".onion") && _config->FindB("Acquire::BlockDotOnion", true)) { // TRANSLATOR: %s is e.g. Tor's ".onion" which would likely fail or leak info (RFC7686) _error->Error(_("Direct connection to %s domains is blocked by default."), ".onion"); if (strcmp(Service, "http") == 0) _error->Error(_("If you meant to use Tor remember to use %s instead of %s."), "tor+http", "http"); return false; } return true; } /*}}}*/ // File Descriptor based Fd /*{{{*/ struct FdFd : public MethodFd { int fd = -1; int Fd() APT_OVERRIDE { return fd; } ssize_t Read(void *buf, size_t count) APT_OVERRIDE { return ::read(fd, buf, count); } ssize_t Write(void *buf, size_t count) APT_OVERRIDE { return ::write(fd, buf, count); } int Close() APT_OVERRIDE { int result = 0; if (fd != -1) result = ::close(fd); fd = -1; return result; } }; bool MethodFd::HasPending() { return false; } std::unique_ptr MethodFd::FromFd(int iFd) { FdFd *fd = new FdFd(); fd->fd = iFd; return std::unique_ptr(fd); } /*}}}*/ // DoConnect - Attempt a connect operation /*{{{*/ // --------------------------------------------------------------------- /* This helper function attempts a connection to a single address. */ static bool DoConnect(struct addrinfo *Addr, std::string const &Host, unsigned long TimeOut, std::unique_ptr &Fd, aptMethod *Owner) { // Show a status indicator char Name[NI_MAXHOST]; char Service[NI_MAXSERV]; Fd.reset(new FdFd()); Name[0] = 0; Service[0] = 0; getnameinfo(Addr->ai_addr,Addr->ai_addrlen, Name,sizeof(Name),Service,sizeof(Service), NI_NUMERICHOST|NI_NUMERICSERV); Owner->Status(_("Connecting to %s (%s)"),Host.c_str(),Name); // if that addr did timeout before, we do not try it again if(bad_addr.find(std::string(Name)) != bad_addr.end()) return false; /* If this is an IP rotation store the IP we are using.. If something goes wrong this will get tacked onto the end of the error message */ if (LastHostAddr->ai_next != 0) { std::stringstream ss; ioprintf(ss, _("[IP: %s %s]"),Name,Service); Owner->SetIP(ss.str()); } // Get a socket if ((static_cast(Fd.get())->fd = socket(Addr->ai_family, Addr->ai_socktype, Addr->ai_protocol)) < 0) return _error->Errno("socket",_("Could not create a socket for %s (f=%u t=%u p=%u)"), Name,Addr->ai_family,Addr->ai_socktype,Addr->ai_protocol); SetNonBlock(Fd->Fd(), true); if (connect(Fd->Fd(), Addr->ai_addr, Addr->ai_addrlen) < 0 && errno != EINPROGRESS) return _error->Errno("connect",_("Cannot initiate the connection " "to %s:%s (%s)."),Host.c_str(),Service,Name); /* This implements a timeout for connect by opening the connection nonblocking */ if (WaitFd(Fd->Fd(), true, TimeOut) == false) { bad_addr.insert(bad_addr.begin(), std::string(Name)); Owner->SetFailReason("Timeout"); return _error->Error(_("Could not connect to %s:%s (%s), " "connection timed out"),Host.c_str(),Service,Name); } // Check the socket for an error condition unsigned int Err; unsigned int Len = sizeof(Err); if (getsockopt(Fd->Fd(), SOL_SOCKET, SO_ERROR, &Err, &Len) != 0) return _error->Errno("getsockopt",_("Failed")); if (Err != 0) { errno = Err; if(errno == ECONNREFUSED) Owner->SetFailReason("ConnectionRefused"); else if (errno == ETIMEDOUT) Owner->SetFailReason("ConnectionTimedOut"); bad_addr.insert(bad_addr.begin(), std::string(Name)); return _error->Errno("connect",_("Could not connect to %s:%s (%s)."),Host.c_str(), Service,Name); } return true; } /*}}}*/ // Connect to a given Hostname /*{{{*/ static bool ConnectToHostname(std::string const &Host, int const Port, const char *const Service, int DefPort, std::unique_ptr &Fd, unsigned long const TimeOut, aptMethod *const Owner) { if (ConnectionAllowed(Service, Host) == false) return false; // Convert the port name/number char ServStr[300]; if (Port != 0) snprintf(ServStr,sizeof(ServStr),"%i", Port); else snprintf(ServStr,sizeof(ServStr),"%s", Service); /* We used a cached address record.. Yes this is against the spec but the way we have setup our rotating dns suggests that this is more sensible */ if (LastHost != Host || LastPort != Port) { Owner->Status(_("Connecting to %s"),Host.c_str()); // Free the old address structure if (LastHostAddr != 0) { freeaddrinfo(LastHostAddr); LastHostAddr = 0; LastUsed = 0; } // We only understand SOCK_STREAM sockets. struct addrinfo Hints; memset(&Hints,0,sizeof(Hints)); Hints.ai_socktype = SOCK_STREAM; Hints.ai_flags = 0; #ifdef AI_IDN if (_config->FindB("Acquire::Connect::IDN", true) == true) Hints.ai_flags |= AI_IDN; #endif // see getaddrinfo(3): only return address if system has such a address configured // useful if system is ipv4 only, to not get ipv6, but that fails if the system has // no address configured: e.g. offline and trying to connect to localhost. if (_config->FindB("Acquire::Connect::AddrConfig", true) == true) Hints.ai_flags |= AI_ADDRCONFIG; Hints.ai_protocol = 0; if(_config->FindB("Acquire::ForceIPv4", false) == true) Hints.ai_family = AF_INET; else if(_config->FindB("Acquire::ForceIPv6", false) == true) Hints.ai_family = AF_INET6; else Hints.ai_family = AF_UNSPEC; // if we couldn't resolve the host before, we don't try now if(bad_addr.find(Host) != bad_addr.end()) return _error->Error(_("Could not resolve '%s'"),Host.c_str()); // Resolve both the host and service simultaneously while (1) { int Res; if ((Res = getaddrinfo(Host.c_str(),ServStr,&Hints,&LastHostAddr)) != 0 || LastHostAddr == 0) { if (Res == EAI_NONAME || Res == EAI_SERVICE) { if (DefPort != 0) { snprintf(ServStr, sizeof(ServStr), "%i", DefPort); DefPort = 0; continue; } bad_addr.insert(bad_addr.begin(), Host); Owner->SetFailReason("ResolveFailure"); return _error->Error(_("Could not resolve '%s'"),Host.c_str()); } if (Res == EAI_AGAIN) { Owner->SetFailReason("TmpResolveFailure"); return _error->Error(_("Temporary failure resolving '%s'"), Host.c_str()); } if (Res == EAI_SYSTEM) return _error->Errno("getaddrinfo", _("System error resolving '%s:%s'"), Host.c_str(),ServStr); return _error->Error(_("Something wicked happened resolving '%s:%s' (%i - %s)"), Host.c_str(),ServStr,Res,gai_strerror(Res)); } break; } LastHost = Host; LastPort = Port; } // When we have an IP rotation stay with the last IP. struct addrinfo *CurHost = LastHostAddr; if (LastUsed != 0) CurHost = LastUsed; while (CurHost != 0) { if (DoConnect(CurHost,Host,TimeOut,Fd,Owner) == true) { LastUsed = CurHost; return true; } Fd->Close(); // Ignore UNIX domain sockets do { CurHost = CurHost->ai_next; } while (CurHost != 0 && CurHost->ai_family == AF_UNIX); /* If we reached the end of the search list then wrap around to the start */ if (CurHost == 0 && LastUsed != 0) CurHost = LastHostAddr; // Reached the end of the search cycle if (CurHost == LastUsed) break; if (CurHost != 0) _error->Discard(); } if (_error->PendingError() == true) return false; return _error->Error(_("Unable to connect to %s:%s:"),Host.c_str(),ServStr); } /*}}}*/ // Connect - Connect to a server /*{{{*/ // --------------------------------------------------------------------- /* Performs a connection to the server (including SRV record lookup) */ bool Connect(std::string Host, int Port, const char *Service, int DefPort, std::unique_ptr &Fd, unsigned long TimeOut, aptMethod *Owner) { if (_error->PendingError() == true) return false; if (ConnectionAllowed(Service, Host) == false) return false; if(LastHost != Host || LastPort != Port) { SrvRecords.clear(); if (_config->FindB("Acquire::EnableSrvRecords", true) == true) { GetSrvRecords(Host, DefPort, SrvRecords); // RFC2782 defines that a lonely '.' target is an abort reason if (SrvRecords.size() == 1 && SrvRecords[0].target.empty()) return _error->Error("SRV records for %s indicate that " "%s service is not available at this domain", Host.c_str(), Service); } } size_t stackSize = 0; // try to connect in the priority order of the srv records std::string initialHost{std::move(Host)}; auto const initialPort = Port; while(SrvRecords.empty() == false) { _error->PushToStack(); ++stackSize; // PopFromSrvRecs will also remove the server auto Srv = PopFromSrvRecs(SrvRecords); Host = Srv.target; Port = Srv.port; auto const ret = ConnectToHostname(Host, Port, Service, DefPort, Fd, TimeOut, Owner); if (ret) { while(stackSize--) _error->RevertToStack(); return true; } } Host = std::move(initialHost); Port = initialPort; // we have no (good) SrvRecords for this host, connect right away _error->PushToStack(); ++stackSize; auto const ret = ConnectToHostname(Host, Port, Service, DefPort, Fd, TimeOut, Owner); while(stackSize--) if (ret) _error->RevertToStack(); else _error->MergeWithStack(); return ret; } /*}}}*/ // UnwrapSocks - Handle SOCKS setup /*{{{*/ // --------------------------------------------------------------------- /* This does socks magic */ static bool TalkToSocksProxy(int const ServerFd, std::string const &Proxy, char const *const type, bool const ReadWrite, uint8_t *const ToFrom, unsigned int const Size, unsigned int const Timeout) { if (WaitFd(ServerFd, ReadWrite, Timeout) == false) return _error->Error("Waiting for the SOCKS proxy %s to %s timed out", URI::SiteOnly(Proxy).c_str(), type); if (ReadWrite == false) { if (FileFd::Read(ServerFd, ToFrom, Size) == false) return _error->Error("Reading the %s from SOCKS proxy %s failed", type, URI::SiteOnly(Proxy).c_str()); } else { if (FileFd::Write(ServerFd, ToFrom, Size) == false) return _error->Error("Writing the %s to SOCKS proxy %s failed", type, URI::SiteOnly(Proxy).c_str()); } return true; } bool UnwrapSocks(std::string Host, int Port, URI Proxy, std::unique_ptr &Fd, unsigned long Timeout, aptMethod *Owner) { /* 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()); #define APT_WriteOrFail(TYPE, DATA, LENGTH) \ if (TalkToSocksProxy(Fd->Fd(), ProxyInfo, TYPE, true, DATA, LENGTH, Timeout) == false) \ return false #define APT_ReadOrFail(TYPE, DATA, LENGTH) \ if (TalkToSocksProxy(Fd->Fd(), ProxyInfo, TYPE, false, DATA, LENGTH, Timeout) == false) \ return false if (Host.length() > 255) return _error->Error("Can't use SOCKS5h as hostname %s is too long!", 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 auth = {{0x01, static_cast(Proxy.User.length())}}; std::copy(Proxy.User.begin(), Proxy.User.end(), std::back_inserter(auth)); auth.push_back(static_cast(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(Port)); portu.i = &port; std::vector request = {{0x05, 0x01, 0x00, 0x03, static_cast(Host.length())}}; std::copy(Host.begin(), 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 = Host.rfind('.'); if (lastdot == std::string::npos || Host.substr(lastdot) != ".onion") ; else if (errcode == 0x01) { auto const prevdot = 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(), 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(), Host.c_str(), bindaddr.c_str()); if (WaitFd(Fd->Fd(), true, Timeout) == false) return _error->Error("SOCKS proxy %s reported connection to %s (%s), but timed out", ProxyInfo.c_str(), Host.c_str(), bindaddr.c_str()); #undef APT_ReadOrFail #undef APT_WriteOrFail return true; } /*}}}*/ // UnwrapTLS - Handle TLS connections /*{{{*/ // --------------------------------------------------------------------- /* Performs a TLS handshake on the socket */ struct TlsFd : public MethodFd { std::unique_ptr UnderlyingFd; gnutls_session_t session; gnutls_certificate_credentials_t credentials; std::string hostname; int Fd() APT_OVERRIDE { return UnderlyingFd->Fd(); } ssize_t Read(void *buf, size_t count) APT_OVERRIDE { return HandleError(gnutls_record_recv(session, buf, count)); } ssize_t Write(void *buf, size_t count) APT_OVERRIDE { return HandleError(gnutls_record_send(session, buf, count)); } template T HandleError(T err) { if (err < 0 && gnutls_error_is_fatal(err)) errno = EIO; else if (err < 0) errno = EAGAIN; else errno = 0; return err; } int Close() APT_OVERRIDE { if (HandleError(gnutls_bye(session, GNUTLS_SHUT_RDWR)) < 0) return -1; return UnderlyingFd->Close(); } bool HasPending() APT_OVERRIDE { return gnutls_record_check_pending(session) > 0; } }; bool UnwrapTLS(std::string Host, std::unique_ptr &Fd, unsigned long Timeout, aptMethod *Owner) { if (_config->FindB("Acquire::AllowTLS", true) == false) return _error->Error("TLS support has been disabled: Acquire::AllowTLS is false."); int err; TlsFd *tlsFd = new TlsFd(); tlsFd->hostname = Host; tlsFd->UnderlyingFd = MethodFd::FromFd(-1); // For now gnutls_init(&tlsFd->session, GNUTLS_CLIENT | GNUTLS_NONBLOCK); gnutls_transport_set_int(tlsFd->session, dynamic_cast(Fd.get())->fd); gnutls_certificate_allocate_credentials(&tlsFd->credentials); // Credential setup if ((err = gnutls_certificate_set_x509_system_trust(tlsFd->credentials)) <= 0) return _error->Error("Could not load TLS certificates: %s", err == 0 ? "No certificates available. Try installing ca-certificates." : gnutls_strerror(err)); std::string fileinfo = Owner->ConfigFind("CaInfo", ""); if (!fileinfo.empty()) { gnutls_certificate_set_verify_flags(tlsFd->credentials, GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT); err = gnutls_certificate_set_x509_trust_file(tlsFd->credentials, fileinfo.c_str(), GNUTLS_X509_FMT_PEM); if (err < 0) return _error->Error("Could not load CaInfo certificate: %s", gnutls_strerror(err)); } // TODO: IssuerCert AKA CURLOPT_ISSUERCERT // TODO: Emulate SslForceVersion AKA CURLOPT_SSLVERSION? // For client authentication, certificate file ... std::string const cert = Owner->ConfigFind("SslCert", ""); std::string const key = Owner->ConfigFind("SslKey", ""); if (cert.empty() == false) { if ((err = gnutls_certificate_set_x509_key_file( tlsFd->credentials, cert.c_str(), key.empty() ? cert.c_str() : key.c_str(), GNUTLS_X509_FMT_PEM)) < 0) { return _error->Error("Could not load client certificate or key: %s", gnutls_strerror(err)); } } // CRL file std::string const crlfile = Owner->ConfigFind("CrlFile", ""); if (crlfile.empty() == false) { if ((err = gnutls_certificate_set_x509_crl_file(tlsFd->credentials, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0) return _error->Error("Could not load CrlFile: %s", gnutls_strerror(err)); } if ((err = gnutls_credentials_set(tlsFd->session, GNUTLS_CRD_CERTIFICATE, tlsFd->credentials)) < 0) return _error->Error("Could not set CaInfo certificate: %s", gnutls_strerror(err)); if ((err = gnutls_set_default_priority(tlsFd->session)) < 0) return _error->Error("Could not set algorithm preferences: %s", gnutls_strerror(err)); if (Owner->ConfigFindB("Verify-Peer", true) || Owner->ConfigFindB("Verify-Host", true)) { gnutls_session_set_verify_cert(tlsFd->session, tlsFd->hostname.c_str(), 0); } if ((err = gnutls_server_name_set(tlsFd->session, GNUTLS_NAME_DNS, tlsFd->hostname.c_str(), tlsFd->hostname.length())) < 0) return _error->Error("Could not set SNI name: %s", gnutls_strerror(err)); // Do the handshake. Our socket is non-blocking, so we need to call WaitFd() // accordingly. do { err = gnutls_handshake(tlsFd->session); if ((err == GNUTLS_E_INTERRUPTED || err == GNUTLS_E_AGAIN) && WaitFd(Fd->Fd(), gnutls_record_get_direction(tlsFd->session) == 1, Timeout) == false) return _error->Errno("select", "Could not wait for server fd"); } while (err < 0 && gnutls_error_is_fatal(err) == 0); if (err < 0) { // Print reason why validation failed. if (err == GNUTLS_E_CERTIFICATE_VERIFICATION_ERROR) { gnutls_datum_t txt; auto type = gnutls_certificate_type_get(tlsFd->session); auto status = gnutls_session_get_verify_cert_status(tlsFd->session); if (gnutls_certificate_verification_status_print(status, type, &txt, 0) == 0) { _error->Error("Certificate verification failed: %s", txt.data); } gnutls_free(txt.data); } return _error->Error("Could not handshake: %s", gnutls_strerror(err)); } tlsFd->UnderlyingFd = std::move(Fd); Fd.reset(tlsFd); return true; } /*}}}*/