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 ZIP user's 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         float total_out_compressed;
 145         float total_in_compressed;
 146         float total_out_uncompressed;
 147         float total_in_uncompressed;
 148
 149  public:
 150
 151         ModuleZLib(InspIRCd* Me)
 152                 : Module::Module(Me)
 153         {
 154                 ServerInstance->PublishInterface("InspSocketHook", this);
 155
 156                 total_out_compressed = total_in_compressed = 0;
 157                 total_out_uncompressed = total_out_uncompressed = 0;
 158         }
 159
 160         virtual ~ModuleZLib()
 161         {
 162         }
 163
 164         virtual Version GetVersion()
 165         {
 166                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 167         }
 168
 169         void Implements(char* List)
 170         {
 171                 List[I_OnRawSocketConnect] = List[I_OnRawSocketAccept] = List[I_OnRawSocketClose] = List[I_OnRawSocketRead] = List[I_OnRawSocketWrite] = 1;
 172                 List[I_OnStats] = List[I_OnRequest] = 1;
 173         }
 174
 175         virtual char* OnRequest(Request* request)
 176         {
 177                 ISHRequest* ISR = (ISHRequest*)request;
 178                 if (strcmp("IS_NAME", request->GetId()) == 0)
 179                 {
 180                         return "zip";
 181                 }
 182                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 183                 {
 184                         char* ret = "OK";
 185                         try
 186                         {
 187                                 ret = ServerInstance->Config->AddIOHook((Module*)this, (InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 188                         }
 189                         catch (ModuleException& e)
 190                         {
 191                                 return NULL;
 192                         }
 193                         return ret;
 194                 }
 195                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 196                 {
 197                         return ServerInstance->Config->DelIOHook((InspSocket*)ISR->Sock) ? (char*)"OK" : NULL;
 198                 }
 199                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 200                 {
 201                         return "OK";
 202                 }
 203                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 204                 {
 205                         return NULL;
 206                 }
 207                 return NULL;
 208         }
 209
 210         virtual int OnStats(char symbol, userrec* user, string_list &results)
 211         {
 212                 if (symbol == 'z')
 213                 {
 214                         std::string sn = ServerInstance->Config->ServerName;
 215
 216                         float outbound_r = 100 - ((total_out_compressed / (total_out_uncompressed + 0.001)) * 100);
 217                         float inbound_r = 100 - ((total_in_compressed / (total_in_uncompressed + 0.001)) * 100);
 218
 219                         float total_compressed = total_in_compressed + total_out_compressed;
 220                         float total_uncompressed = total_in_uncompressed + total_out_uncompressed;
 221
 222                         float total_r = 100 - ((total_compressed / (total_uncompressed + 0.001)) * 100);
 223
 224                         char outbound_ratio[MAXBUF], inbound_ratio[MAXBUF], combined_ratio[MAXBUF];
 225
 226                         sprintf(outbound_ratio, "%3.2f%%", outbound_r);
 227                         sprintf(inbound_ratio, "%3.2f%%", inbound_r);
 228                         sprintf(combined_ratio, "%3.2f%%", total_r);
 229
 230                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_compressed   = "+ConvToStr(total_out_compressed));
 231                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_compressed    = "+ConvToStr(total_in_compressed));
 232                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_uncompressed = "+ConvToStr(total_out_uncompressed));
 233                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_uncompressed  = "+ConvToStr(total_in_uncompressed));
 234                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS outbound_ratio        = "+outbound_ratio);
 235                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS inbound_ratio         = "+inbound_ratio);
 236                         results.push_back(sn+" 304 "+user->nick+" :ZIPSTATS combined_ratio        = "+combined_ratio);
 237                         return 0;
 238                 }
 239
 240                 return 0;
 241         }
 242
 243         virtual void OnRawSocketAccept(int fd, const std::string &ip, int localport)
 244         {
 245                 izip_session* session = &sessions[fd];
 246
 247                 /* allocate deflate state */
 248                 session->fd = fd;
 249                 session->status = IZIP_OPEN;
 250
 251                 session->inbuf = new CountedBuffer();
 252                 ServerInstance->Log(DEBUG,"session->inbuf ALLOC = %d, %08x", fd, session->inbuf);
 253
 254                 session->c_stream.zalloc = (alloc_func)0;
 255                 session->c_stream.zfree = (free_func)0;
 256                 session->c_stream.opaque = (voidpf)0;
 257
 258                 session->d_stream.zalloc = (alloc_func)0;
 259                 session->d_stream.zfree = (free_func)0;
 260                 session->d_stream.opaque = (voidpf)0;
 261         }
 262
 263         virtual void OnRawSocketConnect(int fd)
 264         {
 265                 OnRawSocketAccept(fd, "", 0);
 266         }
 267
 268         virtual void OnRawSocketClose(int fd)
 269         {
 270                 CloseSession(&sessions[fd]);
 271         }
 272
 273         virtual int OnRawSocketRead(int fd, char* buffer, unsigned int count, int &readresult)
 274         {
 275                 izip_session* session = &sessions[fd];
 276
 277                 if (session->status == IZIP_CLOSED)
 278                         return 1;
 279
 280                 unsigned char compr[CHUNK + 1];
 281                 unsigned int offset = 0;
 282                 unsigned int total_size = 0;
 283
 284                 readresult = read(fd, compr, CHUNK);
 285
 286                 if (readresult > 0)
 287                 {
 288                         session->inbuf->AddData(compr, readresult);
 289
 290                         int size = 0;
 291                         while ((size = session->inbuf->GetFrame(compr, CHUNK)) != 0)
 292                         {
 293                                 session->d_stream.next_in  = (Bytef*)compr;
 294                                 session->d_stream.avail_in = 0;
 295                                 session->d_stream.next_out = (Bytef*)(buffer + offset);
 296                                 if (inflateInit(&session->d_stream) != Z_OK)
 297                                         return -EBADF;
 298
 299                                 while ((session->d_stream.total_out < count) && (session->d_stream.total_in < (unsigned int)size))
 300                                 {
 301                                         session->d_stream.avail_in = session->d_stream.avail_out = 1;
 302                                         if (inflate(&session->d_stream, Z_NO_FLUSH) == Z_STREAM_END)
 303                                                 break;
 304                                 }
 305
 306                                 inflateEnd(&session->d_stream);
 307
 308                                 total_in_compressed += readresult;
 309                                 total_size += session->d_stream.total_out;
 310                                 readresult = session->d_stream.total_out;
 311                                 total_in_uncompressed += session->d_stream.total_out;
 312                         }
 313
 314                         buffer[total_size] = 0;
 315
 316                 }
 317                 return (readresult > 0);
 318         }
 319
 320         virtual int OnRawSocketWrite(int fd, const char* buffer, int count)
 321         {
 322                 ServerInstance->Log(DEBUG,"Compressing %d bytes", count);
 323
 324                 izip_session* session = &sessions[fd];
 325                 int ocount = count;
 326
 327                 if (!count)
 328                 {
 329                         ServerInstance->Log(DEBUG,"Nothing to do!");
 330                         return 1;
 331                 }
 332
 333                 if(session->status != IZIP_OPEN)
 334                 {
 335                         CloseSession(session);
 336                         return -1;
 337                 }
 338
 339                 unsigned char compr[CHUNK];
 340
 341                 if (deflateInit(&session->c_stream, Z_BEST_COMPRESSION) != Z_OK)
 342                 {
 343                         ServerInstance->Log(DEBUG,"Deflate init failed");
 344                 }
 345
 346                 session->c_stream.next_in  = (Bytef*)buffer;
 347                 session->c_stream.next_out = compr+4;
 348
 349                 while ((session->c_stream.total_in < (unsigned int)count) && (session->c_stream.total_out < CHUNK))
 350                 {
 351                         session->c_stream.avail_in = session->c_stream.avail_out = 1; /* force small buffers */
 352                         if (deflate(&session->c_stream, Z_NO_FLUSH) != Z_OK)
 353                         {
 354                                 ServerInstance->Log(DEBUG,"Couldnt deflate!");
 355                                 CloseSession(session);
 356                                 return 0;
 357                         }
 358                 }
 359                 /* Finish the stream, still forcing small buffers: */
 360                 for (;;)
 361                 {
 362                         session->c_stream.avail_out = 1;
 363                         if (deflate(&session->c_stream, Z_FINISH) == Z_STREAM_END)
 364                                 break;
 365                 }
 366
 367                 deflateEnd(&session->c_stream);
 368
 369                 total_out_uncompressed += ocount;
 370                 total_out_compressed += session->c_stream.total_out;
 371
 372                 int x = htonl(session->c_stream.total_out);
 373                 /** XXX: We memcpy it onto the start of the buffer like this to save ourselves a write().
 374                  * A memcpy of 4 or so bytes is less expensive and gives the tcp stack more chance of
 375                  * assembling the frame size into the same packet as the compressed frame.
 376                  */
 377                 memcpy(compr, &x, sizeof(x));
 378
 379                 session->outbuf.append((const char*)compr, session->c_stream.total_out+4);
 380
 381                 int ret = write(fd, session->outbuf.data(), session->outbuf.length());
 382
 383                 if (ret > 0)
 384                         session->outbuf = session->outbuf.substr(ret);
 385                 else if (ret < 1)
 386                 {
 387                         if (ret == -1)
 388                         {
 389                                 if (errno == EAGAIN)
 390                                         return 0;
 391                                 else
 392                                 {
 393                                         session->outbuf = "";
 394                                         return -1;
 395                                 }
 396                         }
 397                         else
 398                         {
 399                                 session->outbuf = "";
 400                                 return -1;
 401                         }
 402                 }
 403
 404                 ServerInstance->Log(DEBUG,"Sending frame of size %d", ntohl(x));
 405
 406                 /* ALL LIES the lot of it, we havent really written
 407                  * this amount, but the layer above doesnt need to know.
 408                  */
 409                 return ocount;
 410         }
 411
 412         void CloseSession(izip_session* session)
 413         {
 414                 if (session->status = IZIP_OPEN)
 415                 {
 416                         session->status = IZIP_CLOSED;
 417                         session->outbuf = "";
 418                         delete session->inbuf;
 419                 }
 420         }
 421
 422 };
 423
 424 class ModuleZLibFactory : public ModuleFactory
 425 {
 426  public:
 427         ModuleZLibFactory()
 428         {
 429         }
 430
 431         ~ModuleZLibFactory()
 432         {
 433         }
 434
 435         virtual Module * CreateModule(InspIRCd* Me)
 436         {
 437                 return new ModuleZLib(Me);
 438         }
 439 };
 440
 441
 442 extern "C" void * init_module( void )
 443 {
 444         return new ModuleZLibFactory;
 445 }