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