src/modules/extra/m_ziplink.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 #include "zlib.h"
  18
  19 #include "inspircd_config.h"
  20 #include "configreader.h"
  21 #include "users.h"
  22 #include "channels.h"
  23 #include "modules.h"
  24
  25 #include "socket.h"
  26 #include "hashcomp.h"
  27 #include "inspircd.h"
  28
  29 #include "transport.h"
  30
  31 /* $ModDesc: Provides zlib link support for servers */
  32 /* $LinkerFlags: -lz */
  33 /* $ModDep: transport.h */
  34
  35 /*
  36  * Compressed data is transmitted across the link in the following format:
  37  *
  38  *   0   1   2   3   4 ... n
  39  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  40  * |       n       |              Z0 -> Zn                         |
  41  * +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
  42  *
  43  * Where: n is the size of a frame, in network byte order, 4 bytes.
  44  * Z0 through Zn are Zlib compressed data, n bytes in length.
  45  *
  46  * If the module fails to read the entire frame, then it will buffer
  47  * the portion of the last frame it received, then attempt to read
  48  * the next part of the frame next time a write notification arrives.
  49  *
  50  * ZLIB_BEST_COMPRESSION (9) is used for all sending of data with
  51  * a flush after each frame. A frame may contain multiple lines
  52  * and should be treated as raw binary data.
  53  *
  54  */
  55
  56 /* Status of a connection */
  57 enum izip_status { IZIP_OPEN, IZIP_CLOSED };
  58
  59 /* Maximum transfer size per read operation */
  60 const unsigned int CHUNK = 128 * 1024;
  61
  62 /* This class manages a compressed chunk of data preceeded by
  63  * a length count.
  64  *
  65  * It can handle having multiple chunks of data in the buffer
  66  * at any time.
  67  */
  68 class CountedBuffer : public classbase
  69 {
  70         std::string buffer;             /* Current buffer contents */
  71         unsigned int amount_expected;   /* Amount of data expected */
  72  public:
  73         CountedBuffer()
  74         {
  75                 amount_expected = 0;
  76         }
  77
  78         /** Adds arbitrary compressed data to the buffer.
  79          * - Binsry safe, of course.
  80          */
  81         void AddData(unsigned char* data, int data_length)
  82         {
  83                 buffer.append((const char*)data, data_length);
  84                 this->NextFrameSize();
  85         }
  86
  87         /** Works out the size of the next compressed frame
  88          */
  89         void NextFrameSize()
  90         {
  91                 if ((!amount_expected) && (buffer.length() >= 4))
  92                 {
  93                         /* We have enough to read an int -
  94                          * Yes, this is safe, but its ugly. Give me
  95                          * a nicer way to read 4 bytes from a binary
  96                          * stream, and push them into a 32 bit int,
  97                          * and i'll consider replacing this.
  98                          */
  99                         amount_expected = ntohl((buffer[3] << 24) | (buffer[2] << 16) | (buffer[1] << 8) | buffer[0]);
 100                         buffer = buffer.substr(4);
 101                 }
 102         }
 103
 104         /** Gets the next frame and returns its size, or returns
 105          * zero if there isnt one available yet.
 106          * A frame can contain multiple plaintext lines.
 107          * - Binary safe.
 108          */
 109         int GetFrame(unsigned char* frame, int maxsize)
 110         {
 111                 if (amount_expected)
 112                 {
 113                         /* We know how much we're expecting...
 114                          * Do we have enough yet?
 115                          */
 116                         if (buffer.length() >= amount_expected)
 117                         {
 118                                 int j = 0;
 119                                 for (unsigned int i = 0; i < amount_expected; i++, j++)
 120                                         frame[i] = buffer[i];
 121
 122                                 buffer = buffer.substr(j);
 123                                 amount_expected = 0;
 124                                 NextFrameSize();
 125                                 return j;
 126                         }
 127                 }
 128                 /* Not enough for a frame yet, COME AGAIN! */
 129                 return 0;
 130         }
 131 };
 132
 133 /** Represents an zipped connections extra data
 134  */
 135 class izip_session : public classbase
 136 {
 137  public:
 138         z_stream c_stream;      /* compression stream */
 139         z_stream d_stream;      /* decompress stream */
 140         izip_status status;     /* Connection status */
 141         int fd;                 /* File descriptor */
 142         CountedBuffer* inbuf;   /* Holds input buffer */
 143         std::string outbuf;     /* Holds output buffer */
 144 };
 145
 146 class ModuleZLib : public Module
 147 {
 148         izip_session sessions[MAX_DESCRIPTORS];
 149
 150         /* Used for stats z extensions */
 151         float total_out_compressed;
 152         float total_in_compressed;
 153         float total_out_uncompressed;
 154         float total_in_uncompressed;
 155
 156  public:
 157
 158         ModuleZLib(InspIRCd* Me)
 159                 : Module::Module(Me)
 160         {
 161                 ServerInstance->PublishInterface("InspSocketHook", this);
 162
 163                 total_out_compressed = total_in_compressed = 0;
 164                 total_out_uncompressed = total_out_uncompressed = 0;
 165         }
 166
 167         virtual ~ModuleZLib()
 168         {
 169                 ServerInstance->UnpublishInterface("InspSocketHook", this);
 170         }
 171
 172         virtual Version GetVersion()
 173         {
 174                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 175         }
 176
 177         void Implements(char* List)
 178         {
 179                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 180                 List[I_OnStats] = List[I_OnRequest] = 1;
 181         }
 182
 183         /* Handle InspSocketHook API requests */
 184         virtual char* OnRequest(Request* request)
 185         {
 186                 ISHRequest* ISR = (ISHRequest*)request;
 187                 if (strcmp("IS_NAME", request->GetId()) == 0)
 188                 {
 189                         /* Return name */
 190                         return "zip";
 191                 }
 192                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 193                 {
 194                         /* Attach to an inspsocket */
 195                         char* ret = "OK";
 196                         try
 197                         {
 198                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 199                         }
 200                         catch (ModuleException& e)
 201                         {
 202                                 return NULL;
 203                         }
 204                         return ret;
 205                 }
 206                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 207                 {
 208                         /* Detatch from an inspsocket */
 209                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 210                 }
 211                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 212                 {
 213                         /* Check for completion of handshake
 214                          * (actually, this module doesnt handshake)
 215                          */
 216                         return "OK";
 217                 }
 218                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 219                 {
 220                         /* Attach certificate data to the inspsocket
 221                          * (this module doesnt do that, either)
 222                          */
 223                         return NULL;
 224                 }
 225                 return NULL;
 226         }
 227
 228         /* Handle stats z (misc stats) */
 229         virtual int OnStats(char symbol, userrec* user, string_list &results)
 230         {
 231                 if (symbol == 'z')
 232                 {
 233                         std::string sn = ServerInstance->Config->ServerName;
 234
 235                         /* Yeah yeah, i know, floats are ew.
 236                          * We used them here because we'd be casting to float anyway to do this maths,
 237                          * and also only floating point numbers can deal with the pretty large numbers
 238                          * involved in the total throughput of a server over a large period of time.
 239                          * (we dont count 64 bit ints because not all systems have 64 bit ints, and floats
 240                          * can still hold more.
 241                          */
 242                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 243                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 244
 245                         float total_compressed = total_in_compressed + total_out_compressed;
 246                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 247
 248                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 249
 250                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 251
 252                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 253                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 254                         sprintf(combined_ratio, "%3.2f%%", total_r);
 255
 256                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 257                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 258                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 259                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 260                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 261                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 262                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 263                         return 0;
 264                 }
 265
 266                 return 0;
 267         }
 268
 269         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 270         {
 271                 izip_session* session = &sessions[fd];
 272
 273                 /* allocate state and buffers */
 274                 session->fd = fd;
 275                 session->status = IZIP_OPEN;
 276                 session->inbuf = new CountedBuffer();
 277
 278                 session->c_stream.zalloc = (alloc_func)0;
 279                 session->c_stream.zfree = (free_func)0;
 280                 session->c_stream.opaque = (voidpf)0;
 281
 282                 session->d_stream.zalloc = (alloc_func)0;
 283                 session->d_stream.zfree = (free_func)0;
 284                 session->d_stream.opaque = (voidpf)0;
 285         }
 286
 287         virtual void OnRawSocketConnect(int fd)
 288         {
 289                 /* Nothing special needs doing here compared to accept() */
 290                 OnRawSocketAccept(fd, "", 0);
 291         }
 292
 293         virtual void OnRawSocketClose(int fd)
 294         {
 295                 CloseSession(&sessions[fd]);
 296         }
 297
 298         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 299         {
 300                 /* Find the sockets session */
 301                 izip_session* session = &sessions[fd];
 302
 303                 if (session->status == IZIP_CLOSED)
 304                         return 0;
 305
 306                 unsigned char compr[CHUNK + 4];
 307                 unsigned int offset = 0;
 308                 unsigned int total_size = 0;
 309
 310                 /* Read CHUNK bytes at a time to the buffer (usually 128k) */
 311                 readresult = read(fd, compr, CHUNK);
 312
 313                 /* Did we get anything? */
 314                 if (readresult > 0)
 315                 {
 316                         /* Add it to the frame queue */
 317                         session->inbuf->AddData(compr, readresult);
 318                         total_in_compressed += readresult;
 319
 320                         /* Parse all completed frames */
 321                         int size = 0;
 322                         while ((size = session->inbuf->GetFrame(compr, CHUNK)) != 0)
 323                         {
 324                                 session->d_stream.next_in  = (Bytef*)compr;
 325                                 session->d_stream.avail_in = 0;
 326                                 session->d_stream.next_out = (Bytef*)(buffer + offset);
 327
 328                                 /* If we cant call this, well, we're boned. */
 329                                 if (inflateInit(&session->d_stream) != Z_OK)
 330                                         return 0;
 331
 332                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 333                                 {
 334                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 335                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 336                                                 break;
 337                                 }
 338
 339                                 /* Stick a fork in me, i'm done */
 340                                 inflateEnd(&session->d_stream);
 341
 342                                 /* Update counters and offsets */
 343                                 total_size += session->d_stream.total_out;
 344                                 total_in_uncompressed += session->d_stream.total_out;
 345                                 offset += session->d_stream.total_out;
 346                         }
 347
 348                         /* Null-terminate the buffer -- this doesnt harm binary data */
 349                         buffer[total_size] = 0;
 350
 351                         /* Set the read size to the correct total size */
 352                         readresult = total_size;
 353
 354                 }
 355                 return (readresult > 0);
 356         }
 357
 358         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 359         {
 360                 izip_session* session = &sessions[fd];
 361                 int ocount = count;
 362
 363                 if (!count)     /* Nothing to do! */
 364                         return 0;
 365
 366                 if(session->status != IZIP_OPEN)
 367                 {
 368                         /* Seriously, wtf? */
 369                         CloseSession(session);
 370                         return 0;
 371                 }
 372
 373                 unsigned char compr[CHUNK + 4];
 374
 375                 /* Gentlemen, start your engines! */
 376                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 377                 {
 378                         CloseSession(session);
 379                         return 0;
 380                 }
 381
 382                 /* Set buffer sizes (we reserve 4 bytes at the start of the
 383                  * buffer for the length counters)
 384                  */
 385                 session->c_stream.next_in  = (Bytef*)buffer;
 386                 session->c_stream.next_out = compr + 4;
 387
 388                 /* Compress the text */
 389                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 390                 {
 391                         session->c_stream.avail_in = session->c_stream.avail_out = 1;
 392                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 393                         {
 394                                 CloseSession(session);
 395                                 return 0;
 396                         }
 397                 }
 398                 /* Finish the stream */
 399                 for (session->c_stream.avail_out = 1; deflate(&session->c_stream, Z_FINISH) != Z_STREAM_END; session->c_stream.avail_out = 1);
 400                 deflateEnd(&session->c_stream);
 401
 402                 total_out_uncompressed += ocount;
 403                 total_out_compressed += session->c_stream.total_out;
 404
 405                 /** Assemble the frame length onto the frame, in network byte order */
 406                 compr[0] = (session->c_stream.total_out >> 24);
 407                 compr[1] = (session->c_stream.total_out >> 16);
 408                 compr[2] = (session->c_stream.total_out >> 8);
 409                 compr[3] = (session->c_stream.total_out & 0xFF);
 410
 411                 /* Add compressed data plus leading length to the output buffer -
 412                  * Note, we may have incomplete half-sent frames in here.
 413                  */
 414                 session->outbuf.append((const char*)compr, session->c_stream.total_out + 4);
 415
 416                 /* Lets see how much we can send out */
 417                 int ret = write(fd, session->outbuf.data(), session->outbuf.length());
 418
 419                 /* Check for errors, and advance the buffer if any was sent */
 420                 if (ret > 0)
 421                         session->outbuf = session->outbuf.substr(ret);
 422                 else if (ret < 1)
 423                 {
 424                         if (ret == -1)
 425                         {
 426                                 if (errno == EAGAIN)
 427                                         return 0;
 428                                 else
 429                                 {
 430                                         session->outbuf = "";
 431                                         return 0;
 432                                 }
 433                         }
 434                         else
 435                         {
 436                                 session->outbuf = "";
 437                                 return 0;
 438                         }
 439                 }
 440
 441                 /* ALL LIES the lot of it, we havent really written
 442                  * this amount, but the layer above doesnt need to know.
 443                  */
 444                 return ocount;
 445         }
 446
 447         void CloseSession(izip_session* session)
 448         {
 449                 if (session->status = IZIP_OPEN)
 450                 {
 451                         session->status = IZIP_CLOSED;
 452                         session->outbuf = "";
 453                         delete session->inbuf;
 454                 }
 455         }
 456
 457 };
 458
 459 class ModuleZLibFactory : public ModuleFactory
 460 {
 461  public:
 462         ModuleZLibFactory()
 463         {
 464         }
 465
 466         ~ModuleZLibFactory()
 467         {
 468         }
 469
 470         virtual Module * CreateModule(InspIRCd* Me)
 471         {
 472                 return new ModuleZLib(Me);
 473         }
 474 };
 475
 476
 477 extern "C" void * init_module( void )
 478 {
 479         return new ModuleZLibFactory;
 480 }