src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include <zlib.h>
  16 #include "users.h"
  17 #include "channels.h"
  18 #include "modules.h"
  19 #include "socket.h"
  20 #include "hashcomp.h"
  21 #include "transport.h"
  22
  23 #include <iostream>
  24
  25 /* $ModDesc: Provides zlib link support for servers */
  26 /* $LinkerFlags: -lz */
  27 /* $ModDep: transport.h */
  28
  29 /*
  30  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  31  * a flush after each chunk. A frame may contain multiple lines
  32  * and should be treated as raw binary data.
  33  */
  34
  35 /* Status of a connection */
  36 enum izip_status { IZIP_CLOSED = 0, IZIP_OPEN };
  37
  38 /** Represents an zipped connections extra data
  39  */
  40 class izip_session : public classbase
  41 {
  42  public:
  43         z_stream c_stream;      /* compression stream */
  44         z_stream d_stream;      /* uncompress stream */
  45         izip_status status;     /* Connection status */
  46         std::string outbuf;     /* Holds output buffer (compressed) */
  47         std::string inbuf;      /* Holds input buffer (compressed) */
  48 };
  49
  50 class ModuleZLib : public Module
  51 {
  52         izip_session* sessions;
  53
  54         /* Used for stats z extensions */
  55         float total_out_compressed;
  56         float total_in_compressed;
  57         float total_out_uncompressed;
  58         float total_in_uncompressed;
  59
  60         /* Used for reading data from the wire and compressing data to. */
  61         char *net_buffer;
  62         unsigned int net_buffer_size;
  63  public:
  64
  65         ModuleZLib(InspIRCd* Me)
  66                 : Module(Me)
  67         {
  68                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
  69
  70                 sessions = new izip_session[ServerInstance->SE->GetMaxFds()];
  71                 for (int i = 0; i < ServerInstance->SE->GetMaxFds(); i++)
  72                         sessions[i].status = IZIP_CLOSED;
  73
  74                 total_out_compressed = total_in_compressed = 0;
  75                 total_out_uncompressed = total_in_uncompressed = 0;
  76                 Implementation eventlist[] = { I_OnRawSocketConnect, I_OnRawSocketAccept, I_OnRawSocketClose, I_OnRawSocketRead, I_OnRawSocketWrite, I_OnStats, I_OnRequest };
  77                 ServerInstance->Modules->Attach(eventlist, this, 7);
  78
  79                 // Allocate a buffer which is used for reading and writing data
  80                 net_buffer_size = ServerInstance->Config->NetBufferSize;
  81                 net_buffer = new char[net_buffer_size];
  82         }
  83
  84         virtual ~ModuleZLib()
  85         {
  86                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
  87                 delete[] sessions;
  88                 delete[] net_buffer;
  89         }
  90
  91         virtual Version GetVersion()
  92         {
  93                 return Version("$Id$", VF_VENDOR, API_VERSION);
  94         }
  95
  96
  97         /* Handle BufferedSocketHook API requests */
  98         virtual const char* OnRequest(Request* request)
  99         {
 100                 ISHRequest* ISR = (ISHRequest*)request;
 101                 if (strcmp("IS_NAME", request->GetId()) == 0)
 102                 {
 103                         /* Return name */
 104                         return "zip";
 105                 }
 106                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 107                 {
 108                         /* Attach to an inspsocket */
 109                         const char* ret = "OK";
 110                         try
 111                         {
 112                                 ret = ISR->Sock->AddIOHook((Module*)this) ? "OK" : NULL;
 113                         }
 114                         catch (ModuleException& e)
 115                         {
 116                                 return NULL;
 117                         }
 118                         return ret;
 119                 }
 120                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 121                 {
 122                         /* Detach from an inspsocket */
 123                         return ISR->Sock->DelIOHook() ? "OK" : NULL;
 124                 }
 125                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 126                 {
 127                         /* Check for completion of handshake
 128                          * (actually, this module doesnt handshake)
 129                          */
 130                         return "OK";
 131                 }
 132                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 133                 {
 134                         /* Attach certificate data to the inspsocket
 135                          * (this module doesnt do that, either)
 136                          */
 137                         return NULL;
 138                 }
 139                 return NULL;
 140         }
 141
 142         /* Handle stats z (misc stats) */
 143         virtual int OnStats(char symbol, User* user, string_list &results)
 144         {
 145                 if (symbol == 'z')
 146                 {
 147                         std::string sn = ServerInstance->Config->ServerName;
 148
 149                         /* Yeah yeah, i know, floats are ew.
 150                          * We used them here because we'd be casting to float anyway to do this maths,
 151                          * and also only floating point numbers can deal with the pretty large numbers
 152                          * involved in the total throughput of a server over a large period of time.
 153                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
 154                          * can still hold more.
 155                          */
 156                         float outbound_r = (total_out_compressed / (total_out_uncompressed + 0.001)) * 100;
 157                         float inbound_r = (total_in_compressed / (total_in_uncompressed + 0.001)) * 100;
 158
 159                         float total_compressed = total_in_compressed + total_out_compressed;
 160                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 161
 162                         float total_r = (total_compressed / (total_uncompressed + 0.001)) * 100;
 163
 164                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 165
 166                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 167                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 168                         sprintf(combined_ratio, "%3.2f%%", total_r);
 169
 170                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 171                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 172                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 173                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 174                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_original_outbound_traffic        = "+outbound_ratio);
 175                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS percentage_of_orignal_inbound_traffic         = "+inbound_ratio);
 176                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS total_size_of_original_traffic        = "+combined_ratio);
 177                         return 0;
 178                 }
 179
 180                 return 0;
 181         }
 182
 183         virtual void OnRawSocketConnect(int fd)
 184         {
 185                 if ((fd < 0) || (fd > ServerInstance->SE->GetMaxFds() - 1))
 186                         return;
 187
 188                 izip_session* session = &sessions[fd];
 189
 190                 /* Just in case... */
 191                 session->outbuf.clear();
 192
 193                 session->c_stream.zalloc = (alloc_func)0;
 194                 session->c_stream.zfree = (free_func)0;
 195                 session->c_stream.opaque = (voidpf)0;
 196
 197                 session->d_stream.zalloc = (alloc_func)0;
 198                 session->d_stream.zfree = (free_func)0;
 199                 session->d_stream.opaque = (voidpf)0;
 200
 201                 /* If we cant call this, well, we're boned. */
 202                 if (inflateInit(&session->d_stream) != Z_OK)
 203                 {
 204                         session->status = IZIP_CLOSED;
 205                         return;
 206                 }
 207
 208                 /* Same here */
 209                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 210                 {
 211                         inflateEnd(&session->d_stream);
 212                         session->status = IZIP_CLOSED;
 213                         return;
 214                 }
 215
 216                 /* Just in case, do this last */
 217                 session->status = IZIP_OPEN;
 218         }
 219
 220         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 221         {
 222                 /* Nothing special needs doing here compared to connect() */
 223                 OnRawSocketConnect(fd);
 224         }
 225
 226         virtual void OnRawSocketClose(int fd)
 227         {
 228                 CloseSession(&sessions[fd]);
 229         }
 230
 231         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 232         {
 233                 /* Find the sockets session */
 234                 izip_session* session = &sessions[fd];
 235
 236                 if (session->status == IZIP_CLOSED)
 237                         return 0;
 238
 239                 if (session->inbuf.length())
 240                 {
 241                         /* Our input buffer is filling up. This is *BAD*.
 242                          * We can't return more data than fits into buffer
 243                          * (count bytes), so we will generate another read
 244                          * event on purpose by *NOT* reading from 'fd' at all
 245                          * for now.
 246                          */
 247                         readresult = 0;
 248                 }
 249                 else
 250                 {
 251                         /* Read read_buffer_size bytes at a time to the buffer (usually 2.5k) */
 252                         readresult = read(fd, net_buffer, net_buffer_size);
 253
 254                         total_in_compressed += readresult;
 255
 256                         /* Copy the compressed data into our input buffer */
 257                         session->inbuf.append(net_buffer, readresult);
 258                 }
 259
 260                 size_t in_len = session->inbuf.length();
 261
 262                 /* Do we have anything to do? */
 263                 if (in_len <= 0)
 264                         return 0;
 265
 266                 /* Prepare decompression */
 267                 session->d_stream.next_in = (Bytef *)session->inbuf.c_str();
 268                 session->d_stream.avail_in = in_len;
 269
 270                 session->d_stream.next_out = (Bytef*)buffer;
 271                 /* Last byte is reserved for NULL terminating that beast */
 272                 session->d_stream.avail_out = count - 1;
 273
 274                 /* Z_SYNC_FLUSH: Do as much as possible */
 275                 int ret = inflate(&session->d_stream, Z_SYNC_FLUSH);
 276                 /* TODO CloseStream() in here at random places */
 277                 switch (ret)
 278                 {
 279                         case Z_NEED_DICT:
 280                         case Z_STREAM_ERROR:
 281                                 /* This is one of the 'not supposed to happen' things.
 282                                  * Memory corruption, anyone?
 283                                  */
 284                                 Error(session, "General Error. This is not supposed to happen :/");
 285                                 break;
 286                         case Z_DATA_ERROR:
 287                                 Error(session, "Decompression failed, malformed data");
 288                                 break;
 289                         case Z_MEM_ERROR:
 290                                 Error(session, "Out of memory");
 291                                 break;
 292                         case Z_BUF_ERROR:
 293                                 /* This one is non-fatal, buffer is just full
 294                                  * (can't happen here).
 295                                  */
 296                                 Error(session, "Internal error. This is not supposed to happen.");
 297                                 break;
 298                         case Z_STREAM_END:
 299                                 /* This module *never* generates these :/ */
 300                                 Error(session, "End-of-stream marker received");
 301                                 break;
 302                         case Z_OK:
 303                                 break;
 304                         default:
 305                                 /* NO WAI! This can't happen. All errors are handled above. */
 306                                 Error(session, "Unknown error");
 307                                 break;
 308                 }
 309                 if (ret != Z_OK)
 310                 {
 311                         readresult = 0;
 312                         return 0;
 313                 }
 314
 315                 /* Update the inbut buffer */
 316                 unsigned int input_compressed = in_len - session->d_stream.avail_in;
 317                 session->inbuf = session->inbuf.substr(input_compressed);
 318
 319                 /* Update counters (Old size - new size) */
 320                 unsigned int uncompressed_length = (count - 1) - session->d_stream.avail_out;
 321                 total_in_uncompressed += uncompressed_length;
 322
 323                 /* Null-terminate the buffer -- this doesnt harm binary data */
 324                 buffer[uncompressed_length] = 0;
 325
 326                 /* Set the read size to the correct total size */
 327                 readresult = uncompressed_length;
 328
 329                 return 1;
 330         }
 331
 332         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 333         {
 334                 izip_session* session = &sessions[fd];
 335
 336                 if (!count)     /* Nothing to do! */
 337                         return 0;
 338
 339                 if(session->status != IZIP_OPEN)
 340                         /* Seriously, wtf? */
 341                         return 0;
 342
 343                 int ret;
 344
 345                 /* This loop is really only supposed to run once, but in case 'compr'
 346                  * is filled up somehow we are prepared to handle this situation.
 347                  */
 348                 unsigned int offset = 0;
 349                 do
 350                 {
 351                         /* Prepare compression */
 352                         session->c_stream.next_in = (Bytef*)buffer + offset;
 353                         session->c_stream.avail_in = count - offset;
 354
 355                         session->c_stream.next_out = (Bytef*)net_buffer;
 356                         session->c_stream.avail_out = net_buffer_size;
 357
 358                         /* Compress the text */
 359                         ret = deflate(&session->c_stream, Z_SYNC_FLUSH);
 360                         /* TODO CloseStream() in here at random places */
 361                         switch (ret)
 362                         {
 363                                 case Z_OK:
 364                                         break;
 365                                 case Z_BUF_ERROR:
 366                                         /* This one is non-fatal, buffer is just full
 367                                          * (can't happen here).
 368                                          */
 369                                         Error(session, "Internal error. This is not supposed to happen.");
 370                                         break;
 371                                 case Z_STREAM_ERROR:
 372                                         /* This is one of the 'not supposed to happen' things.
 373                                          * Memory corruption, anyone?
 374                                          */
 375                                         Error(session, "General Error. This is also not supposed to happen.");
 376                                         break;
 377                                 default:
 378                                         Error(session, "Unknown error");
 379                                         break;
 380                         }
 381
 382                         if (ret != Z_OK)
 383                                 return 0;
 384
 385                         /* Space before - space after stuff was added to this */
 386                         unsigned int compressed = net_buffer_size - session->c_stream.avail_out;
 387                         unsigned int uncompressed = count - session->c_stream.avail_in;
 388
 389                         /* Make it skip the data which was compressed already */
 390                         offset += uncompressed;
 391
 392                         /* Update stats */
 393                         total_out_uncompressed += uncompressed;
 394                         total_out_compressed += compressed;
 395
 396                         /* Add compressed to the output buffer */
 397                         session->outbuf.append((const char*)net_buffer, compressed);
 398                 } while (session->c_stream.avail_in != 0);
 399
 400                 /* Lets see how much we can send out */
 401                 ret = write(fd, session->outbuf.data(), session->outbuf.length());
 402
 403                 /* Check for errors, and advance the buffer if any was sent */
 404                 if (ret > 0)
 405                         session->outbuf = session->outbuf.substr(ret);
 406                 else if (ret < 1)
 407                 {
 408                         if (errno == EAGAIN)
 409                                 return 0;
 410                         else
 411                         {
 412                                 session->outbuf.clear();
 413                                 return 0;
 414                         }
 415                 }
 416
 417                 /* ALL LIES the lot of it, we havent really written
 418                  * this amount, but the layer above doesnt need to know.
 419                  */
 420                 return count;
 421         }
 422
 423         void Error(izip_session* session, const std::string &text)
 424         {
 425                 ServerInstance->SNO->WriteToSnoMask('l', "ziplink error: " + text);
 426         }
 427
 428         void CloseSession(izip_session* session)
 429         {
 430                 if (session->status == IZIP_OPEN)
 431                 {
 432                         session->status = IZIP_CLOSED;
 433                         session->outbuf.clear();
 434                         inflateEnd(&session->d_stream);
 435                         deflateEnd(&session->c_stream);
 436                 }
 437         }
 438
 439 };
 440
 441 MODULE_INIT(ModuleZLib)
 442