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