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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 /*

  * WARNING: DO NOT USE THIS CODE IN PRODUCTION SYSTEMS.  It is highly likely to

  *          be plagued with the usual problems endemic to C (buffer overflows

  *          and the like).  We don't especially care here (but would accept

  *          patches!) because this is only intended for use in our test

  *          harnesses in controlled situations where input is guaranteed not to

  *          be malicious.

  */

 #include "ScopedNSSTypes.h"

 #include <assert.h>

 #include <stdio.h>

 #include <string>

 #include <vector>

 #include <algorithm>

 #include <stdarg.h>

 #include "prinit.h"

 #include "prerror.h"

 #include "prenv.h"

 #include "prnetdb.h"

 #include "prtpool.h"

 #include "nsAlgorithm.h"

 #include "nss.h"

 #include "key.h"

 #include "ssl.h"

 #include "plhash.h"

 using namespace mozilla;

 using namespace mozilla::psm;

 using std::string;

 using std::vector;

 #define IS_DELIM(m, c)          ((m)[(c) >> 3] & (1 << ((c) & 7)))

 #define SET_DELIM(m, c)         ((m)[(c) >> 3] |= (1 << ((c) & 7)))

 #define DELIM_TABLE_SIZE        32

 // You can set the level of logging by env var SSLTUNNEL_LOG_LEVEL=n, where n

 // is 0 through 3.  The default is 1, INFO level logging.

 enum LogLevel {

   LEVEL_DEBUG = 0,

   LEVEL_INFO = 1,

   LEVEL_ERROR = 2,

   LEVEL_SILENT = 3

 } gLogLevel, gLastLogLevel;

 #define _LOG_OUTPUT(level, func, params) \

 PR_BEGIN_MACRO \

   if (level >= gLogLevel) { \

     gLastLogLevel = level; \

     func params;\

   } \

 PR_END_MACRO

 // The most verbose output

 #define LOG_DEBUG(params) \

   _LOG_OUTPUT(LEVEL_DEBUG, printf, params)

 // Top level informative messages

 #define LOG_INFO(params) \

   _LOG_OUTPUT(LEVEL_INFO, printf, params)

 // Serious errors that must be logged always until completely gag

 #define LOG_ERROR(params) \

   _LOG_OUTPUT(LEVEL_ERROR, eprintf, params)

 // Same as LOG_ERROR, but when logging is set to LEVEL_DEBUG, the message 

 // will be put to the stdout instead of stderr to keep continuity with other 

 // LOG_DEBUG message output

 #define LOG_ERRORD(params) \

 PR_BEGIN_MACRO \

   if (gLogLevel == LEVEL_DEBUG) \

     _LOG_OUTPUT(LEVEL_ERROR, printf, params); \

   else \

     _LOG_OUTPUT(LEVEL_ERROR, eprintf, params); \

 PR_END_MACRO

 // If there is any output written between LOG_BEGIN_BLOCK() and

 // LOG_END_BLOCK() then a new line will be put to the proper output (out/err)

 #define LOG_BEGIN_BLOCK() \

   gLastLogLevel = LEVEL_SILENT;

 #define LOG_END_BLOCK() \

 PR_BEGIN_MACRO \

   if (gLastLogLevel == LEVEL_ERROR) \

     LOG_ERROR(("\n")); \

   if (gLastLogLevel < LEVEL_ERROR) \

     _LOG_OUTPUT(gLastLogLevel, printf, ("\n")); \

 PR_END_MACRO

 int eprintf(const char* str, ...)

 {

   va_list ap;

   va_start(ap, str);

   int result = vfprintf(stderr, str, ap);

   va_end(ap);

   return result;

 }

 // Copied from nsCRT

 char* strtok2(char* string, const char* delims, char* *newStr)

 {

   PR_ASSERT(string);

   char delimTable[DELIM_TABLE_SIZE];

   uint32_t i;

   char* result;

   char* str = string;

   for (i = 0; i < DELIM_TABLE_SIZE; i++)

     delimTable[i] = '\0';

   for (i = 0; delims[i]; i++) {

     SET_DELIM(delimTable, static_cast<uint8_t>(delims[i]));

   }

   // skip to beginning

   while (*str && IS_DELIM(delimTable, static_cast<uint8_t>(*str))) {

     str++;

   }

   result = str;

   // fix up the end of the token

   while (*str) {

     if (IS_DELIM(delimTable, static_cast<uint8_t>(*str))) {

       *str++ = '\0';

       break;

     }

     str++;

   }

   *newStr = str;

   return str == result ? nullptr : result;

 }

 enum client_auth_option {

   caNone = 0,

   caRequire = 1,

   caRequest = 2

 };

 // Structs for passing data into jobs on the thread pool

 typedef struct {

   int32_t listen_port;

   string cert_nickname;

   PLHashTable* host_cert_table;

   PLHashTable* host_clientauth_table;

   PLHashTable* host_redir_table;

 } server_info_t;

 typedef struct {

   PRFileDesc* client_sock;

   PRNetAddr client_addr;

   server_info_t* server_info;

   // the original host in the Host: header for this connection is

   // stored here, for proxied connections

   string original_host;

   // true if no SSL should be used for this connection

   bool http_proxy_only;

   // true if this connection is for a WebSocket

   bool iswebsocket;

 } connection_info_t;

 typedef struct {

   string fullHost;

   bool matched;

 } server_match_t;

 const int32_t BUF_SIZE = 16384;

 const int32_t BUF_MARGIN = 1024;

 const int32_t BUF_TOTAL = BUF_SIZE + BUF_MARGIN;

 struct relayBuffer

 {

   char *buffer, *bufferhead, *buffertail, *bufferend;

   relayBuffer()

   {

     // Leave 1024 bytes more for request line manipulations

     bufferhead = buffertail = buffer = new char[BUF_TOTAL];

     bufferend = buffer + BUF_SIZE;

   }

   ~relayBuffer()

   {

     delete [] buffer;

   }

   void compact() {

     if (buffertail == bufferhead)

       buffertail = bufferhead = buffer;

   }

   bool empty() { return bufferhead == buffertail; }

   size_t areafree() { return bufferend - buffertail; }

   size_t margin() { return areafree() + BUF_MARGIN; }

   size_t present() { return buffertail - bufferhead; }

 };

 // These numbers are multiplied by the number of listening ports (actual

 // servers running).  According the thread pool implementation there is no

 // need to limit the number of threads initially, threads are allocated

 // dynamically and stored in a linked list.  Initial number of 2 is chosen

 // to allocate a thread for socket accept and preallocate one for the first

 // connection that is with high probability expected to come.

 const uint32_t INITIAL_THREADS = 2;

 const uint32_t MAX_THREADS = 100;

 const uint32_t DEFAULT_STACKSIZE = (512 * 1024);

 // global data

 string nssconfigdir;

 vector<server_info_t> servers;

 PRNetAddr remote_addr;

 PRNetAddr websocket_server;

 PRThreadPool* threads = nullptr;

 PRLock* shutdown_lock = nullptr;

 PRCondVar* shutdown_condvar = nullptr;

 // Not really used, unless something fails to start

 bool shutdown_server = false;

 bool do_http_proxy = false;

 bool any_host_spec_config = false;

 int ClientAuthValueComparator(const void *v1, const void *v2)

 {

   int a = *static_cast<const client_auth_option*>(v1) -

           *static_cast<const client_auth_option*>(v2);

   if (a == 0)

     return 0;

   if (a > 0)

     return 1;

   else // (a < 0)

     return -1;

 }

 static int match_hostname(PLHashEntry *he, int index, void* arg)

 {

   server_match_t *match = (server_match_t*)arg;

   if (match->fullHost.find((char*)he->key) != string::npos)

     match->matched = true;

   return HT_ENUMERATE_NEXT;

 }

 /*

  * Signal the main thread that the application should shut down.

  */

 void SignalShutdown()

 {

   PR_Lock(shutdown_lock);

   PR_NotifyCondVar(shutdown_condvar);

   PR_Unlock(shutdown_lock);

 }

 bool ReadConnectRequest(server_info_t* server_info, 

     relayBuffer& buffer, int32_t* result, string& certificate,

     client_auth_option* clientauth, string& host, string& location)

 {

   if (buffer.present() < 4) {

     LOG_DEBUG((" !! only %d bytes present in the buffer", (int)buffer.present()));

     return false;

   }

   if (strncmp(buffer.buffertail-4, "\r\n\r\n", 4)) {

     LOG_ERRORD((" !! request is not tailed with CRLFCRLF but with %x %x %x %x", 

                *(buffer.buffertail-4),

                *(buffer.buffertail-3),

                *(buffer.buffertail-2),

                *(buffer.buffertail-1)));

     return false;

   }

   LOG_DEBUG((" parsing initial connect request, dump:\n%.*s\n", (int)buffer.present(), buffer.bufferhead));

   *result = 400;

   char* token;

   char* _caret;

   token = strtok2(buffer.bufferhead, " ", &_caret);

   if (!token) {

     LOG_ERRORD((" no space found"));

     return true;

   }

   if (strcmp(token, "CONNECT")) {

     LOG_ERRORD((" not CONNECT request but %s", token));

     return true;

   }

   token = strtok2(_caret, " ", &_caret);

   void* c = PL_HashTableLookup(server_info->host_cert_table, token);

   if (c)

     certificate = static_cast<char*>(c);

   host = "https://";

   host += token;

   c = PL_HashTableLookup(server_info->host_clientauth_table, token);

   if (c)

     *clientauth = *static_cast<client_auth_option*>(c);

   else

     *clientauth = caNone;

   void *redir = PL_HashTableLookup(server_info->host_redir_table, token);

   if (redir)

     location = static_cast<char*>(redir);

   token = strtok2(_caret, "/", &_caret);

   if (strcmp(token, "HTTP")) {  

     LOG_ERRORD((" not tailed with HTTP but with %s", token));

     return true;

   }

   *result = (redir) ? 302 : 200;

   return true;

 }

 bool ConfigureSSLServerSocket(PRFileDesc* socket, server_info_t* si, string &certificate, client_auth_option clientAuth)

 {

   const char* certnick = certificate.empty() ?

       si->cert_nickname.c_str() : certificate.c_str();

   ScopedCERTCertificate cert(PK11_FindCertFromNickname(certnick, nullptr));

   if (!cert) {

     LOG_ERROR(("Failed to find cert %s\n", certnick));

     return false;

   }

   ScopedSECKEYPrivateKey privKey(PK11_FindKeyByAnyCert(cert, nullptr));

   if (!privKey) {

     LOG_ERROR(("Failed to find private key\n"));

     return false;

   }

   PRFileDesc* ssl_socket = SSL_ImportFD(nullptr, socket);

   if (!ssl_socket) {

     LOG_ERROR(("Error importing SSL socket\n"));

     return false;

   }

   SSLKEAType certKEA = NSS_FindCertKEAType(cert);

   if (SSL_ConfigSecureServer(ssl_socket, cert, privKey, certKEA)

       != SECSuccess) {

     LOG_ERROR(("Error configuring SSL server socket\n"));

     return false;

   }

   SSL_OptionSet(ssl_socket, SSL_SECURITY, true);

   SSL_OptionSet(ssl_socket, SSL_HANDSHAKE_AS_CLIENT, false);

   SSL_OptionSet(ssl_socket, SSL_HANDSHAKE_AS_SERVER, true);

   if (clientAuth != caNone)

   {

     SSL_OptionSet(ssl_socket, SSL_REQUEST_CERTIFICATE, true);

     SSL_OptionSet(ssl_socket, SSL_REQUIRE_CERTIFICATE, clientAuth == caRequire);

   }

   SSL_ResetHandshake(ssl_socket, true);

   return true;

 }

 /**

  * This function examines the buffer for a Sec-WebSocket-Location: field, 

  * and if it's present, it replaces the hostname in that field with the

  * value in the server's original_host field.  This function works

  * in the reverse direction as AdjustWebSocketHost(), replacing the real

  * hostname of a response with the potentially fake hostname that is expected

  * by the browser (e.g., mochi.test).

  *

  * @return true if the header was adjusted successfully, or not found, false

  * if the header is present but the url is not, which should indicate

  * that more data needs to be read from the socket

  */

 bool AdjustWebSocketLocation(relayBuffer& buffer, connection_info_t *ci)

 {

   assert(buffer.margin());

   buffer.buffertail[1] = '\0';

   char* wsloc = strstr(buffer.bufferhead, "Sec-WebSocket-Location:");

   if (!wsloc)

     return true;

   // advance pointer to the start of the hostname

   wsloc = strstr(wsloc, "ws://");

   if (!wsloc)

     return false;

   wsloc += 5;

   // find the end of the hostname

   char* wslocend = strchr(wsloc + 1, '/');

   if (!wslocend)

     return false;

   char *crlf = strstr(wsloc, "\r\n");

   if (!crlf)

     return false;

   if (ci->original_host.empty())

     return true;

   int diff = ci->original_host.length() - (wslocend-wsloc);

   if (diff > 0)

     assert(size_t(diff) <= buffer.margin());

   memmove(wslocend + diff, wslocend, buffer.buffertail - wsloc - diff);

   buffer.buffertail += diff;

   memcpy(wsloc, ci->original_host.c_str(), ci->original_host.length());

   return true;

 }

 /**

  * This function examines the buffer for a Host: field, and if it's present,

  * it replaces the hostname in that field with the hostname in the server's

  * remote_addr field.  This is needed because proxy requests may be coming

  * from mochitest with fake hosts, like mochi.test, and these need to be

  * replaced with the host that the destination server is actually running

  * on.

  */

 bool AdjustWebSocketHost(relayBuffer& buffer, connection_info_t *ci)

 {

   const char HEADER_UPGRADE[] = "Upgrade:";

   const char HEADER_HOST[] = "Host:";

   PRNetAddr inet_addr = (websocket_server.inet.port ? websocket_server :

     remote_addr);

   assert(buffer.margin());

   // Cannot use strnchr so add a null char at the end. There is always some

   // space left because we preserve a margin.

   buffer.buffertail[1] = '\0';

   // Verify this is a WebSocket header.

   char* h1 = strstr(buffer.bufferhead, HEADER_UPGRADE);

   if (!h1)

     return false;

   h1 += strlen(HEADER_UPGRADE);

   h1 += strspn(h1, " \t");

   char* h2 = strstr(h1, "WebSocket\r\n");

   if (!h2) h2 = strstr(h1, "websocket\r\n");

   if (!h2) h2 = strstr(h1, "Websocket\r\n");

   if (!h2)

     return false;

   char* host = strstr(buffer.bufferhead, HEADER_HOST);

   if (!host)

     return false;

   // advance pointer to beginning of hostname

   host += strlen(HEADER_HOST);

   host += strspn(host, " \t");

   char* endhost = strstr(host, "\r\n");

   if (!endhost)

     return false;

   // Save the original host, so we can use it later on responses from the

   // server.

   ci->original_host.assign(host, endhost-host);

   char newhost[40];

   PR_NetAddrToString(&inet_addr, newhost, sizeof(newhost));

   assert(strlen(newhost) < sizeof(newhost) - 7);

   sprintf(newhost, "%s:%d", newhost, PR_ntohs(inet_addr.inet.port));

   int diff = strlen(newhost) - (endhost-host);

   if (diff > 0)

     assert(size_t(diff) <= buffer.margin());

   memmove(endhost + diff, endhost, buffer.buffertail - host - diff);

   buffer.buffertail += diff;

   memcpy(host, newhost, strlen(newhost));

   return true;

 }

 /**

  * This function prefixes Request-URI path with a full scheme-host-port

  * string.

  */

 bool AdjustRequestURI(relayBuffer& buffer, string *host)

 {

   assert(buffer.margin());

   // Cannot use strnchr so add a null char at the end. There is always some space left

   // because we preserve a margin.

   buffer.buffertail[1] = '\0';

   LOG_DEBUG((" incoming request to adjust:\n%s\n", buffer.bufferhead));

   char *token, *path;

   path = strchr(buffer.bufferhead, ' ') + 1;

   if (!path)

     return false;

   // If the path doesn't start with a slash don't change it, it is probably '*' or a full

   // path already. Return true, we are done with this request adjustment.

   if (*path != '/')

     return true;

   token = strchr(path, ' ') + 1;

   if (!token)

     return false;

   if (strncmp(token, "HTTP/", 5))

     return false;

   size_t hostlength = host->length();

   assert(hostlength <= buffer.margin());

   memmove(path + hostlength, path, buffer.buffertail - path);

   memcpy(path, host->c_str(), hostlength);

   buffer.buffertail += hostlength;

   return true;

 }

 bool ConnectSocket(PRFileDesc *fd, const PRNetAddr *addr, PRIntervalTime timeout)

 {

   PRStatus stat = PR_Connect(fd, addr, timeout);

   if (stat != PR_SUCCESS)

     return false;

   PRSocketOptionData option;

   option.option = PR_SockOpt_Nonblocking;

   option.value.non_blocking = true;

   PR_SetSocketOption(fd, &option);

   return true;

 }

 /*

  * Handle an incoming client connection. The server thread has already

  * accepted the connection, so we just need to connect to the remote

  * port and then proxy data back and forth.

  * The data parameter is a connection_info_t*, and must be deleted

  * by this function.

  */

 void HandleConnection(void* data)

 {

   connection_info_t* ci = static_cast<connection_info_t*>(data);

   PRIntervalTime connect_timeout = PR_SecondsToInterval(30);

   ScopedPRFileDesc other_sock(PR_NewTCPSocket());

   bool client_done = false;

   bool client_error = false;

   bool connect_accepted = !do_http_proxy;

   bool ssl_updated = !do_http_proxy;

   bool expect_request_start = do_http_proxy;

   string certificateToUse;

   string locationHeader;

   client_auth_option clientAuth;

   string fullHost;

   LOG_DEBUG(("SSLTUNNEL(%p)): incoming connection csock(0)=%p, ssock(1)=%p\n",

          static_cast<void*>(data),

          static_cast<void*>(ci->client_sock),

          static_cast<void*>(other_sock)));

   if (other_sock) 

   {

     int32_t numberOfSockets = 1;

     relayBuffer buffers[2];

     if (!do_http_proxy)

     {

       if (!ConfigureSSLServerSocket(ci->client_sock, ci->server_info, certificateToUse, caNone))

         client_error = true;

       else if (!ConnectSocket(other_sock, &remote_addr, connect_timeout))

         client_error = true;

       else

         numberOfSockets = 2;

     }

     PRPollDesc sockets[2] = 

     { 

       {ci->client_sock, PR_POLL_READ, 0},

       {other_sock, PR_POLL_READ, 0}

     };

     bool socketErrorState[2] = {false, false};

     while (!((client_error||client_done) && buffers[0].empty() && buffers[1].empty()))

     {

       sockets[0].in_flags |= PR_POLL_EXCEPT;

       sockets[1].in_flags |= PR_POLL_EXCEPT;

       LOG_DEBUG(("SSLTUNNEL(%p)): polling flags csock(0)=%c%c, ssock(1)=%c%c\n",

                  static_cast<void*>(data),

                  sockets[0].in_flags & PR_POLL_READ  ? 'R' : '-',

                  sockets[0].in_flags & PR_POLL_WRITE ? 'W' : '-',

                  sockets[1].in_flags & PR_POLL_READ  ? 'R' : '-',

                  sockets[1].in_flags & PR_POLL_WRITE ? 'W' : '-'));

       int32_t pollStatus = PR_Poll(sockets, numberOfSockets, PR_MillisecondsToInterval(1000));

       if (pollStatus < 0)

       {

         LOG_DEBUG(("SSLTUNNEL(%p)): pollStatus=%d, exiting\n",

                    static_cast<void*>(data), pollStatus));

         client_error = true;

         break;

       }

       if (pollStatus == 0)

       {

         // timeout

         LOG_DEBUG(("SSLTUNNEL(%p)): poll timeout, looping\n",

                    static_cast<void*>(data)));

         continue;

       }

       for (int32_t s = 0; s < numberOfSockets; ++s)

       {

         int32_t s2 = s == 1 ? 0 : 1;

         int16_t out_flags = sockets[s].out_flags;

         int16_t &in_flags = sockets[s].in_flags;

         int16_t &in_flags2 = sockets[s2].in_flags;

         sockets[s].out_flags = 0;

         LOG_BEGIN_BLOCK();

         LOG_DEBUG(("SSLTUNNEL(%p)): %csock(%d)=%p out_flags=%d",

                    static_cast<void*>(data),

                    s == 0 ? 'c' : 's',

                    s,

                    static_cast<void*>(sockets[s].fd),

                    out_flags));

         if (out_flags & (PR_POLL_EXCEPT | PR_POLL_ERR | PR_POLL_HUP))

         {

           LOG_DEBUG((" :exception\n"));

           client_error = true;

           socketErrorState[s] = true;

           // We got a fatal error state on the socket. Clear the output buffer

           // for this socket to break the main loop, we will never more be able

           // to send those data anyway.

           buffers[s2].bufferhead = buffers[s2].buffertail = buffers[s2].buffer;

           continue;

         } // PR_POLL_EXCEPT, PR_POLL_ERR, PR_POLL_HUP handling

         if (out_flags & PR_POLL_READ && !buffers[s].areafree())

         {

            LOG_DEBUG((" no place in read buffer but got read flag, dropping it now!"));

            in_flags &= ~PR_POLL_READ;

         }

         if (out_flags & PR_POLL_READ && buffers[s].areafree())

         {

           LOG_DEBUG((" :reading"));

           int32_t bytesRead = PR_Recv(sockets[s].fd, buffers[s].buffertail, 

               buffers[s].areafree(), 0, PR_INTERVAL_NO_TIMEOUT);

           if (bytesRead == 0)

           {

             LOG_DEBUG((" socket gracefully closed"));

             client_done = true;

             in_flags &= ~PR_POLL_READ;

           }

           else if (bytesRead < 0)

           {

             if (PR_GetError() != PR_WOULD_BLOCK_ERROR)

             {

               LOG_DEBUG((" error=%d", PR_GetError()));

               // We are in error state, indicate that the connection was 

               // not closed gracefully

               client_error = true;

               socketErrorState[s] = true;

               // Wipe out our send buffer, we cannot send it anyway.

               buffers[s2].bufferhead = buffers[s2].buffertail = buffers[s2].buffer;

             }

             else

               LOG_DEBUG((" would block"));

           }

           else

           {

             // If the other socket is in error state (unable to send/receive)

             // throw this data away and continue loop

             if (socketErrorState[s2])

             {

               LOG_DEBUG((" have read but other socket is in error state\n"));

               continue;

             }

             buffers[s].buffertail += bytesRead;

             LOG_DEBUG((", read %d bytes", bytesRead));

             // We have to accept and handle the initial CONNECT request here

             int32_t response;

             if (!connect_accepted && ReadConnectRequest(ci->server_info, buffers[s],

                 &response, certificateToUse, &clientAuth, fullHost, locationHeader))

             {

               // Mark this as a proxy-only connection (no SSL) if the CONNECT

               // request didn't come for port 443 or from any of the server's

               // cert or clientauth hostnames.

               if (fullHost.find(":443") == string::npos)

               {

                 server_match_t match;

                 match.fullHost = fullHost;

                 match.matched = false;

                 PL_HashTableEnumerateEntries(ci->server_info->host_cert_table, 

                                              match_hostname, 

                                              &match);

                 PL_HashTableEnumerateEntries(ci->server_info->host_clientauth_table, 

                                              match_hostname, 

                                              &match);

                 ci->http_proxy_only = !match.matched;

               }

               else

               {

                 ci->http_proxy_only = false;

               }

               // Clean the request as it would be read

               buffers[s].bufferhead = buffers[s].buffertail = buffers[s].buffer;

               in_flags |= PR_POLL_WRITE;

               connect_accepted = true;

               // Store response to the oposite buffer

               if (response == 200)

               {

                   LOG_DEBUG((" accepted CONNECT request, connected to the server, sending OK to the client\n"));

                   strcpy(buffers[s2].buffer, "HTTP/1.1 200 Connected\r\nConnection: keep-alive\r\n\r\n");

               }

               else if (response == 302)

               {

                   LOG_DEBUG((" accepted CONNECT request with redirection, "

                              "sending location and 302 to the client\n"));

                   client_done = true;

                   sprintf(buffers[s2].buffer, 

                           "HTTP/1.1 302 Moved\r\n"

                           "Location: https://%s/\r\n"

                           "Connection: close\r\n\r\n",

                           locationHeader.c_str());

               }

               else

               {

                 LOG_ERRORD((" could not read the connect request, closing connection with %d", response));

                 client_done = true;

                 sprintf(buffers[s2].buffer, "HTTP/1.1 %d ERROR\r\nConnection: close\r\n\r\n", response);

                 break;

               }

               buffers[s2].buffertail = buffers[s2].buffer + strlen(buffers[s2].buffer);

               // Send the response to the client socket

               break;

             } // end of CONNECT handling

             if (!buffers[s].areafree())

             {

               // Do not poll for read when the buffer is full

               LOG_DEBUG((" no place in our read buffer, stop reading"));

               in_flags &= ~PR_POLL_READ;

             }

             if (ssl_updated)

             {

               if (s == 0 && expect_request_start) 

               {

                 if (!strstr(buffers[s].bufferhead, "\r\n\r\n"))

                 {

                   // We haven't received the complete header yet, so wait.

                   continue;

                 }

                 else

                 {

                   ci->iswebsocket = AdjustWebSocketHost(buffers[s], ci);

                   expect_request_start = !(ci->iswebsocket || 

                                            AdjustRequestURI(buffers[s], &fullHost));

                   PRNetAddr* addr = &remote_addr;

                   if (ci->iswebsocket && websocket_server.inet.port)

                     addr = &websocket_server;

                   if (!ConnectSocket(other_sock, addr, connect_timeout))

                   {

                     LOG_ERRORD((" could not open connection to the real server\n"));

                     client_error = true;

                     break;

                   }

                   LOG_DEBUG(("\n connected to remote server\n"));

                   numberOfSockets = 2;

                 }

               }

               else if (s == 1 && ci->iswebsocket)

               {

                 if (!AdjustWebSocketLocation(buffers[s], ci))

                   continue;

               }

               in_flags2 |= PR_POLL_WRITE;

               LOG_DEBUG((" telling the other socket to write"));

             }

             else

               LOG_DEBUG((" we have something for the other socket to write, but ssl has not been administered on it"));

           }

         } // PR_POLL_READ handling

         if (out_flags & PR_POLL_WRITE)

         {

           LOG_DEBUG((" :writing"));

           int32_t bytesWrite = PR_Send(sockets[s].fd, buffers[s2].bufferhead, 

               buffers[s2].present(), 0, PR_INTERVAL_NO_TIMEOUT);

           if (bytesWrite < 0)

           {

             if (PR_GetError() != PR_WOULD_BLOCK_ERROR) {

               LOG_DEBUG((" error=%d", PR_GetError()));

               client_error = true;

               socketErrorState[s] = true;

               // We got a fatal error while writting the buffer. Clear it to break

               // the main loop, we will never more be able to send it.

               buffers[s2].bufferhead = buffers[s2].buffertail = buffers[s2].buffer;

             }

             else

               LOG_DEBUG((" would block"));

           }

           else

           {

             LOG_DEBUG((", written %d bytes", bytesWrite));

             buffers[s2].buffertail[1] = '\0';

             LOG_DEBUG((" dump:\n%.*s\n", bytesWrite, buffers[s2].bufferhead));

             buffers[s2].bufferhead += bytesWrite;

             if (buffers[s2].present())

             {

               LOG_DEBUG((" still have to write %d bytes", (int)buffers[s2].present()));

               in_flags |= PR_POLL_WRITE;

             }              

             else

             {

               if (!ssl_updated)

               {

                 LOG_DEBUG((" proxy response sent to the client"));

                 // Proxy response has just been writen, update to ssl

                 ssl_updated = true;

                 if (ci->http_proxy_only)

                 {

                   LOG_DEBUG((" not updating to SSL based on http_proxy_only for this socket"));

                 }

                 else if (!ConfigureSSLServerSocket(ci->client_sock, ci->server_info, 

                                                    certificateToUse, clientAuth))

                 {

                   LOG_ERRORD((" failed to config server socket\n"));

                   client_error = true;

                   break;

                 }

                 else

                 {

                   LOG_DEBUG((" client socket updated to SSL"));

                 }

               } // sslUpdate

               LOG_DEBUG((" dropping our write flag and setting other socket read flag"));

               in_flags &= ~PR_POLL_WRITE;

               in_flags2 |= PR_POLL_READ;

               buffers[s2].compact();

             }

           }

         } // PR_POLL_WRITE handling

         LOG_END_BLOCK(); // end the log

       } // for...

     } // while, poll

   }

   else

     client_error = true;

   LOG_DEBUG(("SSLTUNNEL(%p)): exiting root function for csock=%p, ssock=%p\n",

              static_cast<void*>(data),

              static_cast<void*>(ci->client_sock),

              static_cast<void*>(other_sock)));

   if (!client_error)

     PR_Shutdown(ci->client_sock, PR_SHUTDOWN_SEND);

   PR_Close(ci->client_sock);

   delete ci;

 }

 /*

  * Start listening for SSL connections on a specified port, handing

  * them off to client threads after accepting the connection.

  * The data parameter is a server_info_t*, owned by the calling

  * function.

  */

 void StartServer(void* data)

 {

   server_info_t* si = static_cast<server_info_t*>(data);

   //TODO: select ciphers?

   ScopedPRFileDesc listen_socket(PR_NewTCPSocket());

   if (!listen_socket) {

     LOG_ERROR(("failed to create socket\n"));

     SignalShutdown();

     return;

   }

   // In case the socket is still open in the TIME_WAIT state from a previous

   // instance of ssltunnel we ask to reuse the port.

   PRSocketOptionData socket_option;

   socket_option.option = PR_SockOpt_Reuseaddr;

   socket_option.value.reuse_addr = true;

   PR_SetSocketOption(listen_socket, &socket_option);

   PRNetAddr server_addr;

   PR_InitializeNetAddr(PR_IpAddrAny, si->listen_port, &server_addr);

   if (PR_Bind(listen_socket, &server_addr) != PR_SUCCESS) {

     LOG_ERROR(("failed to bind socket\n"));

     SignalShutdown();

     return;

   }

   if (PR_Listen(listen_socket, 1) != PR_SUCCESS) {

     LOG_ERROR(("failed to listen on socket\n"));

     SignalShutdown();

     return;

   }

   LOG_INFO(("Server listening on port %d with cert %s\n", si->listen_port,

          si->cert_nickname.c_str()));

   while (!shutdown_server) {

     connection_info_t* ci = new connection_info_t();

     ci->server_info = si;

     ci->http_proxy_only = do_http_proxy;

     // block waiting for connections

     ci->client_sock = PR_Accept(listen_socket, &ci->client_addr,

                                 PR_INTERVAL_NO_TIMEOUT);

     PRSocketOptionData option;

     option.option = PR_SockOpt_Nonblocking;

     option.value.non_blocking = true;

     PR_SetSocketOption(ci->client_sock, &option);

     if (ci->client_sock)

       // Not actually using this PRJob*...

       //PRJob* job =

       PR_QueueJob(threads, HandleConnection, ci, true);

     else

       delete ci;

   }

 }

 // bogus password func, just don't use passwords. :-P

 char* password_func(PK11SlotInfo* slot, PRBool retry, void* arg)

 {

   if (retry)

     return nullptr;

   return PL_strdup("");

 }

 server_info_t* findServerInfo(int portnumber)

 {

   for (vector<server_info_t>::iterator it = servers.begin();

        it != servers.end(); it++) 

   {

     if (it->listen_port == portnumber)

       return &(*it);

   }

   return nullptr;

 }

 int processConfigLine(char* configLine)

 {

   if (*configLine == 0 || *configLine == '#')

     return 0;

   char* _caret;

   char* keyword = strtok2(configLine, ":", &_caret);

   // Configure usage of http/ssl tunneling proxy behavior

   if (!strcmp(keyword, "httpproxy"))

   {

     char* value = strtok2(_caret, ":", &_caret);

     if (!strcmp(value, "1"))

       do_http_proxy = true;

     return 0;

   }

   if (!strcmp(keyword, "websocketserver"))

   {

     char* ipstring = strtok2(_caret, ":", &_caret);

     if (PR_StringToNetAddr(ipstring, &websocket_server) != PR_SUCCESS) {

       LOG_ERROR(("Invalid IP address in proxy config: %s\n", ipstring));

       return 1;

     }

     char* remoteport = strtok2(_caret, ":", &_caret);

     int port = atoi(remoteport);

     if (port <= 0) {

       LOG_ERROR(("Invalid remote port in proxy config: %s\n", remoteport));

       return 1;

     }

     websocket_server.inet.port = PR_htons(port);

     return 0;

   }

   // Configure the forward address of the target server

   if (!strcmp(keyword, "forward"))

   {

     char* ipstring = strtok2(_caret, ":", &_caret);

     if (PR_StringToNetAddr(ipstring, &remote_addr) != PR_SUCCESS) {

       LOG_ERROR(("Invalid remote IP address: %s\n", ipstring));

       return 1;

     }

     char* serverportstring = strtok2(_caret, ":", &_caret);

     int port = atoi(serverportstring);

     if (port <= 0) {

       LOG_ERROR(("Invalid remote port: %s\n", serverportstring));

       return 1;

     }

     remote_addr.inet.port = PR_htons(port);

     return 0;

   }

   // Configure all listen sockets and port+certificate bindings

   if (!strcmp(keyword, "listen"))

   {

     char* hostname = strtok2(_caret, ":", &_caret);

     char* hostportstring = nullptr;

     if (strcmp(hostname, "*"))

     {

       any_host_spec_config = true;

       hostportstring = strtok2(_caret, ":", &_caret);

     }

     char* serverportstring = strtok2(_caret, ":", &_caret);

     char* certnick = strtok2(_caret, ":", &_caret);

     int port = atoi(serverportstring);

     if (port <= 0) {

       LOG_ERROR(("Invalid port specified: %s\n", serverportstring));

       return 1;

     }

     if (server_info_t* existingServer = findServerInfo(port))

     {

       char *certnick_copy = new char[strlen(certnick)+1];

       char *hostname_copy = new char[strlen(hostname)+strlen(hostportstring)+2];

       strcpy(hostname_copy, hostname);

       strcat(hostname_copy, ":");

       strcat(hostname_copy, hostportstring);

       strcpy(certnick_copy, certnick);

       PLHashEntry* entry = PL_HashTableAdd(existingServer->host_cert_table, hostname_copy, certnick_copy);

       if (!entry) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

     }

     else

     {

       server_info_t server;

       server.cert_nickname = certnick;

       server.listen_port = port;

       server.host_cert_table = PL_NewHashTable(0, PL_HashString, PL_CompareStrings,

                                                PL_CompareStrings, nullptr, nullptr);

       if (!server.host_cert_table)

       {

         LOG_ERROR(("Internal, could not create hash table\n"));

         return 1;

       }

       server.host_clientauth_table = PL_NewHashTable(0, PL_HashString, PL_CompareStrings,

                                                      ClientAuthValueComparator, nullptr, nullptr);

       if (!server.host_clientauth_table)

       {

         LOG_ERROR(("Internal, could not create hash table\n"));

         return 1;

       }

       server.host_redir_table = PL_NewHashTable(0, PL_HashString, PL_CompareStrings,

                                                 PL_CompareStrings, nullptr, nullptr);

       if (!server.host_redir_table)

       {

         LOG_ERROR(("Internal, could not create hash table\n"));

         return 1;

       }

       servers.push_back(server);

     }

     return 0;

   }

   if (!strcmp(keyword, "clientauth"))

   {

     char* hostname = strtok2(_caret, ":", &_caret);

     char* hostportstring = strtok2(_caret, ":", &_caret);

     char* serverportstring = strtok2(_caret, ":", &_caret);

     int port = atoi(serverportstring);

     if (port <= 0) {

       LOG_ERROR(("Invalid port specified: %s\n", serverportstring));

       return 1;

     }

     if (server_info_t* existingServer = findServerInfo(port))

     {

       char* authoptionstring = strtok2(_caret, ":", &_caret);

       client_auth_option* authoption = new client_auth_option;

       if (!authoption) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

       if (!strcmp(authoptionstring, "require"))

         *authoption = caRequire;

       else if (!strcmp(authoptionstring, "request"))

         *authoption = caRequest;

       else if (!strcmp(authoptionstring, "none"))

         *authoption = caNone;

       else

       {

         LOG_ERROR(("Incorrect client auth option modifier for host '%s'", hostname));

         return 1;

       }

       any_host_spec_config = true;

       char *hostname_copy = new char[strlen(hostname)+strlen(hostportstring)+2];

       if (!hostname_copy) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

       strcpy(hostname_copy, hostname);

       strcat(hostname_copy, ":");

       strcat(hostname_copy, hostportstring);

       PLHashEntry* entry = PL_HashTableAdd(existingServer->host_clientauth_table, hostname_copy, authoption);

       if (!entry) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

     }

     else

     {

       LOG_ERROR(("Server on port %d for client authentication option is not defined, use 'listen' option first", port));

       return 1;

     }

     return 0;

   }

   if (!strcmp(keyword, "redirhost"))

   {

     char* hostname = strtok2(_caret, ":", &_caret);

     char* hostportstring = strtok2(_caret, ":", &_caret);

     char* serverportstring = strtok2(_caret, ":", &_caret);

     int port = atoi(serverportstring);

     if (port <= 0) {

       LOG_ERROR(("Invalid port specified: %s\n", serverportstring));

       return 1;

     }

     if (server_info_t* existingServer = findServerInfo(port))

     {

       char* redirhoststring = strtok2(_caret, ":", &_caret);

       any_host_spec_config = true;

       char *hostname_copy = new char[strlen(hostname)+strlen(hostportstring)+2];

       if (!hostname_copy) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

       strcpy(hostname_copy, hostname);

       strcat(hostname_copy, ":");

       strcat(hostname_copy, hostportstring);

       char *redir_copy = new char[strlen(redirhoststring)+1];

       strcpy(redir_copy, redirhoststring);

       PLHashEntry* entry = PL_HashTableAdd(existingServer->host_redir_table, hostname_copy, redir_copy);

       if (!entry) {

         LOG_ERROR(("Out of memory"));

         return 1;

       }

     }

     else

     {

       LOG_ERROR(("Server on port %d for redirhost option is not defined, use 'listen' option first", port));

       return 1;

     }

     return 0;

   }

   // Configure the NSS certificate database directory

   if (!strcmp(keyword, "certdbdir"))

   {

     nssconfigdir = strtok2(_caret, "\n", &_caret);

     return 0;

   }

   LOG_ERROR(("Error: keyword \"%s\" unexpected\n", keyword));

   return 1;

 }

 int parseConfigFile(const char* filePath)

 {

   FILE* f = fopen(filePath, "r");

   if (!f)

     return 1;

   char buffer[1024], *b = buffer;

   while (!feof(f))

   {

     char c;

     fscanf(f, "%c", &c);

     switch (c)

     {

     case '\n':

       *b++ = 0;

       if (processConfigLine(buffer))

         return 1;

       b = buffer;

     case '\r':

       continue;

     default:

       *b++ = c;

     }

   }

   fclose(f);

   // Check mandatory items

   if (nssconfigdir.empty())

   {

     LOG_ERROR(("Error: missing path to NSS certification database\n,use certdbdir:<path> in the config file\n"));

     return 1;

   }

   if (any_host_spec_config && !do_http_proxy)

   {

     LOG_ERROR(("Warning: any host-specific configurations are ignored, add httpproxy:1 to allow them\n"));

   }

   return 0;

 }

 int freeHostCertHashItems(PLHashEntry *he, int i, void *arg)

 {

   delete [] (char*)he->key;

   delete [] (char*)he->value;

   return HT_ENUMERATE_REMOVE;

 }

 int freeHostRedirHashItems(PLHashEntry *he, int i, void *arg)

 {

   delete [] (char*)he->key;

   delete [] (char*)he->value;

   return HT_ENUMERATE_REMOVE;

 }

 int freeClientAuthHashItems(PLHashEntry *he, int i, void *arg)

 {

   delete [] (char*)he->key;

   delete (client_auth_option*)he->value;

   return HT_ENUMERATE_REMOVE;

 }

 int main(int argc, char** argv)

 {

   const char* configFilePath;

   const char* logLevelEnv = PR_GetEnv("SSLTUNNEL_LOG_LEVEL");

   gLogLevel = logLevelEnv ? (LogLevel)atoi(logLevelEnv) : LEVEL_INFO;

   if (argc == 1)

     configFilePath = "ssltunnel.cfg";

   else

     configFilePath = argv[1];

   memset(&websocket_server, 0, sizeof(PRNetAddr));

   if (parseConfigFile(configFilePath)) {

     LOG_ERROR(("Error: config file \"%s\" missing or formating incorrect\n"

       "Specify path to the config file as parameter to ssltunnel or \n"

       "create ssltunnel.cfg in the working directory.\n\n"

       "Example format of the config file:\n\n"

       "       # Enable http/ssl tunneling proxy-like behavior.\n"

       "       # If not specified ssltunnel simply does direct forward.\n"

       "       httpproxy:1\n\n"

       "       # Specify path to the certification database used.\n"

       "       certdbdir:/path/to/certdb\n\n"

       "       # Forward/proxy all requests in raw to 127.0.0.1:8888.\n"

       "       forward:127.0.0.1:8888\n\n"

       "       # Accept connections on port 4443 or 5678 resp. and authenticate\n"

       "       # to any host ('*') using the 'server cert' or 'server cert 2' resp.\n"

       "       listen:*:4443:server cert\n"

       "       listen:*:5678:server cert 2\n\n"

       "       # Accept connections on port 4443 and authenticate using\n"

       "       # 'a different cert' when target host is 'my.host.name:443'.\n"

       "       # This only works in httpproxy mode and has higher priority\n"

       "       # than the previous option.\n"

       "       listen:my.host.name:443:4443:a different cert\n\n"

       "       # To make a specific host require or just request a client certificate\n"

       "       # to authenticate use the following options. This can only be used\n"

       "       # in httpproxy mode and only after the 'listen' option has been\n"

       "       # specified. You also have to specify the tunnel listen port.\n"

       "       clientauth:requesting-client-cert.host.com:443:4443:request\n"

       "       clientauth:requiring-client-cert.host.com:443:4443:require\n"

       "       # Proxy WebSocket traffic to the server at 127.0.0.1:9999,\n"

       "       # instead of the server specified in the 'forward' option.\n"

       "       websocketserver:127.0.0.1:9999\n",

       configFilePath));

     return 1;

   }

   // create a thread pool to handle connections

   threads = PR_CreateThreadPool(INITIAL_THREADS * servers.size(),

                                 MAX_THREADS * servers.size(),

                                 DEFAULT_STACKSIZE);

   if (!threads) {

     LOG_ERROR(("Failed to create thread pool\n"));

     return 1;

   }

   shutdown_lock = PR_NewLock();

   if (!shutdown_lock) {

     LOG_ERROR(("Failed to create lock\n"));

     PR_ShutdownThreadPool(threads);

     return 1;

   }

   shutdown_condvar = PR_NewCondVar(shutdown_lock);

   if (!shutdown_condvar) {

     LOG_ERROR(("Failed to create condvar\n"));

     PR_ShutdownThreadPool(threads);

     PR_DestroyLock(shutdown_lock);

     return 1;

   }

   PK11_SetPasswordFunc(password_func);

   // Initialize NSS

   if (NSS_Init(nssconfigdir.c_str()) != SECSuccess) {

     int32_t errorlen = PR_GetErrorTextLength();

     char* err = new char[errorlen+1];

     PR_GetErrorText(err);

     LOG_ERROR(("Failed to init NSS: %s", err));

     delete[] err;

     PR_ShutdownThreadPool(threads);

     PR_DestroyCondVar(shutdown_condvar);

     PR_DestroyLock(shutdown_lock);

     return 1;

   }

   if (NSS_SetDomesticPolicy() != SECSuccess) {

     LOG_ERROR(("NSS_SetDomesticPolicy failed\n"));

     PR_ShutdownThreadPool(threads);

     PR_DestroyCondVar(shutdown_condvar);

     PR_DestroyLock(shutdown_lock);

     NSS_Shutdown();

     return 1;

   }

   // these values should make NSS use the defaults

   if (SSL_ConfigServerSessionIDCache(0, 0, 0, nullptr) != SECSuccess) {

     LOG_ERROR(("SSL_ConfigServerSessionIDCache failed\n"));

     PR_ShutdownThreadPool(threads);

     PR_DestroyCondVar(shutdown_condvar);

     PR_DestroyLock(shutdown_lock);

     NSS_Shutdown();

     return 1;

   }

   for (vector<server_info_t>::iterator it = servers.begin();

        it != servers.end(); it++) {

     // Not actually using this PRJob*...

     // PRJob* server_job =

     PR_QueueJob(threads, StartServer, &(*it), true);

   }

   // now wait for someone to tell us to quit

   PR_Lock(shutdown_lock);

   PR_WaitCondVar(shutdown_condvar, PR_INTERVAL_NO_TIMEOUT);

   PR_Unlock(shutdown_lock);

   shutdown_server = true;

   LOG_INFO(("Shutting down...\n"));

   // cleanup

   PR_ShutdownThreadPool(threads);

   PR_JoinThreadPool(threads);

   PR_DestroyCondVar(shutdown_condvar);

   PR_DestroyLock(shutdown_lock);

   if (NSS_Shutdown() == SECFailure) {

     LOG_DEBUG(("Leaked NSS objects!\n"));

   }

   for (vector<server_info_t>::iterator it = servers.begin();

        it != servers.end(); it++) 

   {

     PL_HashTableEnumerateEntries(it->host_cert_table, freeHostCertHashItems, nullptr);

     PL_HashTableEnumerateEntries(it->host_clientauth_table, freeClientAuthHashItems, nullptr);

     PL_HashTableEnumerateEntries(it->host_redir_table, freeHostRedirHashItems, nullptr);

     PL_HashTableDestroy(it->host_cert_table);

     PL_HashTableDestroy(it->host_clientauth_table);

     PL_HashTableDestroy(it->host_redir_table);

   }

   PR_Cleanup();

   return 0;

 }